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1.
Rev. cuba. invest. bioméd ; 40(2): e1104, 2021. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1347458

ABSTRACT

Introducción: Las plantas medicinales han demostrado poseer propiedades antibacterianas para el control de la periodontitis. Objetivo: Determinar la actividad antibacteriana frente a Porphyromonas gingivalis ATCC 33277 de un gel experimental compuesto por aceite esencial de Eucalyptus globulus Labill. Métodos: Se realizó un estudio experimental in vitro. Se empleó el programa EPi InfoTM para el cálculo de las repeticiones. El aceite esencial se obtuvo por el método de arrastre de vapor; se identificó su composición química por cromatografía de gases acoplada a espectrometría de masas. Se evaluó la concentración mínima inhibitoria (CMI) y concentración mínima bactericida (CMB). Se realizó un ensayo de difusión en Agar para medir los halos de inhibición del gel experimental al 4,46 por ciento frente a P. gingivalis, la comparación con clorhexidina al 0,12 por ciento se evaluó con la prueba U de Mann-Whitney. Se adoptó un nivel de significancia del 5 por ciento . Resultados: Se identificaron 11 constituyentes en el aceite esencial, los principales componentes químicos fueron 3-heptadecene, (Z)- (36,13 por ciento ), 1-tridecene (14,7 por ciento ) y 1,8-cineole (9,72 por ciento ). La CMI del aceite esencial fue 36,195 mg/mL y la CMB fue 39,114 mg/mL. Los halos de inhibición del gel experimental de P. gingivalis fueron 25,533 mm ± 0,960. mm. Se observaron diferencias estadísticamente significativas frente a clorhexidina al 0,12 por ciento (23,282 ± 0,345) (p < 0,05). Conclusiones: El gel experimental al 4,46 por ciento compuesto por aceite esencial de Eucalyptus globulus Labill presentó una actividad antibacteriana importante frente a Porphyromonas gingivalis ATCC 33277(AU)


Introduction: Medicinal plants have proved to have antibacterial properties for the control of periodontitis. Objective: Determine the antibacterial activity against Porphyromonas gingivalis ATCC 33277 of an experimental gel composed of essential Eucalyptus globulus Labill oil. Methods: An in vitro experimental study was conducted. The software EPi InfoTM was used to estimate the repetitions. The essential oil was obtained by steam entrainment, and its chemical composition was determined by gas chromatography / mass spectrometry. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also evaluated. An agar diffusion test was performed to measure the inhibition haloes of the 4.46 percent experimental gel against P. gingivalis. Comparison with 0.12 percent chlorhexidine was evaluated with the Mann-Whitney U test. A 5 percent significance level was adopted. Results: A total 11 constituents were identified in the essential oil. The main chemical components were 3-Heptadecene, (Z)- (36.13 percent), 1-Tridecene (14.7 percentand 1,8-cineole (9.72 percent). MIC of the essential oil was 36.195 mg/ml, whereas MBC was 39.114 mg/ml. The inhibition haloes of the experimental P. gingivalis gel were 25.533 mm ± 0.960 mm. Statistically significant differences were observed versus 0.12 percent chlorhexidine (23.282 ± 0.345) (p < 0.05). Conclusions: The 4.46 percent experimental gel composed of Eucalyptus globulus Labill essential oil displayed considerable antibacterial activity against Porphyromonas gingivalis ATCC 33277(AU)


Subject(s)
Humans , Male , Female , Periodontitis , Oils, Volatile , Chlorhexidine , Mass Spectrometry/methods , In Vitro Techniques , Microbial Sensitivity Tests , Chromatography, Gas/methods , Anti-Bacterial Agents/therapeutic use
2.
Acta bioquím. clín. latinoam ; 54(1): 61-68, mar. 2020. graf, tab
Article in Spanish | LILACS | ID: biblio-1130580

ABSTRACT

El uso de bisfenol-A (BPA) a nivel de la industria global se ha venido incrementando en los ultimos anos, y fueron los mercados emergentes los impulsores de esta demanda creciente. Las aplicaciones de BPA en la industria de los alimentos y bebidas representan solo del 3 al 4% del consumo global de policarbonato, pero su uso esta siendo reexaminado debido a que se conocieron varios trabajos cientificos que indican la existencia de una relacion directa entre el BPA y los efectos adversos para la salud. La contaminacion de los alimentos y bebidas se produce por migracion del BPA desde los envases que los contienen (alimentos enlatados, vinos, etc.), y es la principal fuente de exposicion en el humano. Para evaluar dicha exposicion se desarrollo y valido un metodo analitico por cromatografia gaseosa acoplada a espectrometria de masa para la cuantificacion de BPA total en orina de mujeres embarazadas atendidas en el Hospital Italiano de Buenos Aires en el ano 2013, con un limite de cuantificacion de 2,0 ng/mL y un limite de deteccion de 0,8 ng/mL. De las 149 muestras de orina analizadas, el 66,4% fueron cuantificables, con la mediana de BPA total de 4,8 ng/mL (4,3 ng/mg de creatinina) y la media geometrica de 4,8 ng/mL (4,7 ng/mg de creatinina).


The use of bisphenol-A (BPA) at the level of the global industry has been increasing in recent years, with emerging markets being the drivers of this growing demand. BPA applications in the food and beverage industry represent only 3 to 4% of the global consumption of polycarbonate, but its use is being reexamined because several scientific works were reported indicating the existence of a direct relationship between BPA and adverse effects on health. The contamination of food and beverages is produced by the migration of BPA from the containers that hold them (canned foods, wines, etc.) and it is the main source of exposure in humans. To evaluate this exposure, an analytical method was developed by gas chromatography coupled to mass spectrometry for the quantification of total BPA in urine of pregnant women treated at the Hospital Italiano de Buenos Aires in 2013, with a limit of quantification of 2.0 ng/mL and of detection of 0.8 ng/mL. Of the 149 urine samples analyzed, 66.4% were quantifiable, with a median total BPA of 4.8 ng/mL (4.3 ng/mg creatinine) and a geometric mean of 4.8 ng/mL (4.7 ng/mg creatinine).


O uso de bisfenol-A (BPA) ao nivel da industria global foi aumentando nos ultimos anos, e foram os mercados emergentes que deram impulso a essa demanda crescente. As aplicacoes de BPA na industria de alimentos e bebidas representam apenas 3 a 4% do consumo global de policarbonato, mas seu uso esta sendo reexaminado visto que varios trabalhos cientificos indicando a existencia de uma relacao direta entre o BPA e os efeitos adversos na saude foram conhecidos. A contaminacao dos alimentos e bebidas e produzida pela migracao de BPA das embalagens que os contem (alimentos enlatados, vinhos, etc.) e e a principal fonte de exposicao em humanos. Para avaliar esta exposicao, foi desenvolvido e avaliado um metodo analitico por cromatografia gasosa acoplada a espectrometria de massas para a quantificacao do BPA total na urina de gestantes atendidas no Hospital Italiano de Buenos Aires em 2013, com um limite de quantificacao de 2,0 ng/mL e um limite de deteccao de 0,8 ng/mL. Das 149 amostras de urina analisadas, 66,4% foram quantificaveis, com uma mediana de BPA total de 4,8 ng/mL (4,3 ng/mg de creatinina) e a media geometrica de 4,8 ng/mL (4,7 ng/mg de creatinina).


Subject(s)
Humans , Female , Pregnancy , Urine , Pregnancy/urine , Endocrine Disruptors , Gas Chromatography-Mass Spectrometry/methods , Mass Spectrometry/methods , Toxicology/statistics & numerical data , Food Industry , Health , Chromatography, Gas/methods , Food and Beverages , Pregnant Women , Drug-Related Side Effects and Adverse Reactions , Food
3.
Braz. J. Pharm. Sci. (Online) ; 56: e17194, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132044

ABSTRACT

It is important to study the stability of plant extracts used as active ingredients in phytotherapic medicine, as degradation of the active principles directly affects the efficacy and safety of these products. Therefore, a stability study of the hydroalcoholic extract of the species: Mikania glomerata and Mikania laevigata was conducted in order to determine the speed of degradation and shelf life of these extracts, which are incorporated in cough syrup in Brazil. Leaves of both species were dried in an oven or by lyophilization (freeze-dried). Hydroalcoholic extracts underwent both accelerated stability study of six months and long-term stability study for 12 months. Samples were stored at different temperatures and every three months were analysed by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) to monitor their chemical profile, quantifying coumarin and chlorogenic acid. For all conditions of the study, a reduction of the content of the chemical marker of this species, coumarin, greater than 5% was observed, so a shelf life of two years cannot be assigned to the hydroalcoholic extracts of these species as observed in commercial extracts.


Subject(s)
Plant Extracts/analysis , Efficacy , Asteraceae/classification , Mikania/classification , Mass Spectrometry/methods , Chlorogenic Acid/adverse effects , Chromatography, High Pressure Liquid/methods , Cough , Coumarins/classification
4.
Braz. J. Pharm. Sci. (Online) ; 56: e17836, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132033

ABSTRACT

This study was carried out in order to compare the relative bioavailability of two different formulations containing 400 mg of acetaminophen + 4 mg of phenylephrine hydrochloride + 4 mg of chlorpheniramine maleate, Test formulation (Cimegripe®) and Reference formulation (Resfenol®) in 84 healthy volunteers of both sexes under fasting conditions. The study was conducted in a single dose, randomized, open-label, crossover 3-way and partially replicated. The tolerability was evaluated by the monitoring of adverse events and vital signs, results of clinical and laboratory tests. Plasma concentrations were quantified by validated bioanalytical methods using the ultra-performance liquid chromatography coupled to tandem mass spectrometry. The Cmax, Tmax, AUC0-t, AUC0-inf, T1/2 and Kel pharmacokinetic parameters were calculated from these obtained concentrations. The 90% confidence intervals were constructed for the ratio reference/test from the geometric average of the Cmax and AUC parameters which were comprised between 80% and 125%. Only the Cmax parameter of the phenylephrine was applied the scaled average bioequivalence due to the intraindividual coefficient of variation > 30% obtained, thus extending the acceptance limits of the interval. It can be concluded that the two formulations were bioequivalent in terms of rate and absorption extent and thus interchangeable


Subject(s)
Humans , Male , Female , Phenylephrine/analysis , Capsules/classification , Biological Availability , Chlorpheniramine/analysis , Acetaminophen/analysis , Mass Spectrometry/methods , Single Dose , Fasting/adverse effects , Cross-Over Studies , Monitoring , Absorption/drug effects , Tandem Mass Spectrometry/methods , Healthy Volunteers/classification
5.
Arq. neuropsiquiatr ; 77(10): 696-704, Oct. 2019. tab, graf
Article in English | LILACS | ID: biblio-1038736

ABSTRACT

ABSTRACT The diagnosis of multiple sclerosis (MS) has changed over the last decade, but remains a composite of clinical assessment and magnetic resonance imaging to prove dissemination of lesions in time and space. The intrathecal synthesis of immunoglobulin may be a nonspecific marker and there are no plasma biomarkers that are useful in the diagnosis of MS, presenting additional challenges to their early detection. Methods We performed a preliminary untargeted qualitative lipidomics mass spectrometry analysis, comparing cerebrospinal fluid (CSF) and plasma samples from patients with MS, other inflammatory neurological diseases and idiopathic intracranial hypertension. Results Lipid identification revealed that fatty acids and sphingolipids were the most abundant classes of lipids in the CSF and that glycerolipids and fatty acids were the main class of lipids in the plasma of patients with MS. The area under the curve was 0.995 (0.912-1) and 0.78 (0.583-0.917), respectively. The permutation test indicated that this ion combination was useful for distinguishing MS from other inflammatory diseases (p < 0.001 and 0.055, respectively). Conclusion This study concluded that the CSF and plasma from patients with MS bear a unique lipid signature that can be useful as a diagnostic biomarker.


RESUMO Embora o diagnóstico da EM tenha se modificado na última década, ainda tem como requisito básico a demonstração da disseminação no tempo e no espaço, através do quadro clínico e do exame de ressonância magnética. A síntese intratecal de imunoglobulina pode ser um marcador inespecífico e não há biomarcadores plasmáticos que sejam úteis no diagnóstico da EM, impondo desafios à sua detecção precoce. Métodos Realizamos uma análise lipidômica preliminar por espectrometria de massas, não direcionada, qualitativa, comparando amostras de LCR e plasma de pacientes com EM, outras doenças neurológicas inflamatórias e hipertensão intracraniana idiopática (HII). Resultados A identificação lipídica revelou que os ácidos graxos e esfingolipídios foram as classes mais abundantes de lipídios no LCR e que glicerolipídios e ácidos graxos foram a principal classe de lipídios no plasma de pacientes com EM. A AUC foi de 0,995 (0,912-1) e 0,78 (0,583-0,917), respectivamente. O teste de permutação indicou que essa combinação de íons foi útil para distinguir a EM de outras doenças inflamatórias (p < 0,001 e 0,055, respectivamente). Conclusão Este estudo sugere que o líquido cefalorraquidiano (LCR) e o plasma de pacientes com EM possuem uma assinatura lipídica única, pode ser útil como um biomarcador diagnóstico.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Young Adult , Multiple Sclerosis/cerebrospinal fluid , Multiple Sclerosis/blood , Reference Values , Mass Spectrometry/methods , Magnetic Resonance Imaging , Biomarkers/blood , Reproducibility of Results , Chromatography, Liquid , Sensitivity and Specificity , Lipidomics/methods , Multiple Sclerosis/diagnosis
6.
Rev. argent. microbiol ; 51(2): 148-152, jun. 2019. ilus
Article in Spanish | LILACS | ID: biblio-1013365

ABSTRACT

Se presentan 2 casos de bacteriemia por Helicobacter cinaedi. El primero se diagnosticó en un varón de 76 años y resultó secundario a la colocación de un acceso vascular; el segundo correspondió a un lactante febril de 37 días de vida, asociado a un cuadro de gastroen-terocolitis aguda. H. cinaedi es un microorganismo que presenta dificultad para desarrollarse en diferentes medios de cultivo y lograr su identificación a nivel de especie. En ambos casos fue fundamental la observación microscópica en fresco de las botellas de hemocultivo, la utilización de la espectrometría de masas y la posterior secuenciación del gen hsp60 para llegar a esa instancia. En los últimos anos se han informado infecciones por H. cinaedi con frecuencia creciente en otras partes del mundo. En este trabajo presentamos los primeros casos de bacteriemia por H. cinaedi documentados en Argentina.


Two cases of bacteremia caused by Helicobacter cinaedi are presented. The first case was diagnosed in a 76-year-old male patient, and was secondary to a vascular access device placement; the second case corresponded to a febrile infant of 37 days of life, and was associated with acute gastroenteritis. H. cinaedi is a microorganism difficult to grow in different culture media and also to identify to species level. In both cases, the microscopic observation of blood culture bottles, the use of mass spectrometry and the subsequent sequencing of the hsp60 gene were essential. In the recent literature, H. cinaedi infections are being reported more frequently. In this report we present the first documented cases of bacteremia caused by H. cinaedi in Argentina.


Subject(s)
Humans , Male , Infant , Aged , Helicobacter Infections/diagnosis , Bacteremia/diagnosis , Argentina/epidemiology , Mass Spectrometry/methods , Blood Culture/methods
7.
Rev. argent. microbiol ; 51(1): 22-25, mar. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1041815

ABSTRACT

Las micobacterias de crecimiento rápido son una rara causa de endocarditis bacteriana. Durante las últimas décadas han aumentado las infecciones debido a este tipo de micobacterias, en especial las postraumáticas y las posquirúrgicas. Estas infecciones pueden ser localizadas o diseminadas, y también pueden producir brotes nosocomiales debido a la contaminación del equipamiento médico. Por lo general, las tinciones para bacterias ácido-alcohol resistentes no se emplean de rutina en el procesamiento de hemocultivos positivos. Sin embargo, el microbiólogo debe estar atento al ver un bacilo gram positivo, ya que podría tratarse de una micobacteria de crecimiento rápido. Describimos un caso de endocarditis por de Mycobacterium mageritense en una paciente con parche pericárdico autógeno y un catéter para medir la presión en la aurícula izquierda. La bacteria fue identificada por espectrometría de masas (MALDI-TOF MS), score 2,3, y luego confirmada por secuenciación y análisis del gen ARNr 16s con las bases de datos del NCBI y EzTaxon, con una concordancia del 99,8 y el 100%, respectivamente.


Rapidly growing non-tuberculosis mycobacteria are a rare cause of bacterial endocarditis. During the last decades, there has been an increase in infections due to rapidly growing mycobacteria, mainly after trauma and post-surgical procedures, both localized and disseminated, as well as nosocomial outbreaks due to contamination of medical equipment. Routine acid-fast staining for blood culture bottles is not always performed; however, the microbiologist should be aware of potential RGM infections especially when gram positive bacilli are observed. We describe a case of endocarditis caused by Mycobacterium mageritense in a patient with an autologous pericardial patch and a pressure catheter in the left auricle. The bacterial species was identified as Mycobacterium mageritense by mass spectrometry (MALDI-TOF MS), score 2.3, and confirmed by 16S rRNA analysis with 99.8 and 100% agreement, respectively.


Subject(s)
Humans , Female , Adult , Endocarditis, Bacterial/microbiology , Catheter-Related Infections/diagnosis , Mycobacterium/isolation & purification , Mass Spectrometry/methods , RNA, Ribosomal, 16S/analysis , Catheter-Related Infections/therapy , Blood Culture/methods
8.
São Paulo; s.n; s.n; 2019. 214 p. graf, tab.
Thesis in Portuguese | LILACS | ID: biblio-995689

ABSTRACT

Cloropropanóis são um grupo conhecido de contaminantes relacionados ao processamento de alimentos. Eles são formados na reação entre lipídeos e cloretos quando submetidos ao tratamento térmico, e podem ser encontrados na forma livre ou ligada. O 3-monocloro-1,2-propanediol (3-MCPD), é classificado pela IARC como possível carcinógeno humano (grupo 2B). O glicidol (e seus ésteres), é classificado também pela IARC como uma substância provavelmente carcinogênica para seres humanos (grupo 2A), e, recentemente, vem sendo encontrado em alimentos. O objetivo deste trabalho foi avaliar a presença do 3-MCPD e do glicidol em óleos vegetais comestíveis utilizando a cromatografia gasosa com detector de massa triplo quadrupolo MS/MS. A técnica utilizada foi a preconizada pela AOCS Cd 29c-13, sendo uma análise indireta, e foi possível adaptá-la visando as determinações do 3-MCPD e glicidol através da construção de curvas de calibração e análises de amostras de referência. O método foi validado e os resultados indicaram o limite de detecção do composto 3-MCPD, de 42,4 µg/kg e o limite de quantificação de 50 µg/kg, e para o Glicidol indicaram o limite de detecção de 43,5 µg/kg e limite de quantificação de 50 µg/kg. Os resultados para 3-MCPD obtidos nos ensaios da curva de calibração e linearidade demonstraram que o método foi capaz de expressar resultados com boa linearidade (0 - 10 mg/kg , r2, = 0.9991). Os resultados obtidos nos ensaios de exatidão obedeceram aos critérios de 70 a 120% de recuperação, e ±20% de variação entre os resultados de acordo com SANTE (2017). O método em questão demonstrou ser seletivo, uma vez que não foram observados picos interferentes nos tempos de retenção dos compostos estudados. Os ensaios de precisão nos níveis baixos, médio e alto e robustez demonstraram que o método é robusto e preciso, portanto a validação foi considerada adequada ao uso pretendido. Foram analisadas 368 amostras de óleos vegetais (76 amostras de óleo de canola, 48 amostras de óleo de milho, 69 amostras de óleo de algodão, 33 amostras de óleo de palma, 10 amostras de óleo de palmiste, 50 amostras de oleína de palma, 30 amostras de óleo de soja e 51 amostras de óleo de girassol). As concentrações das amostras analisadas apresentaram resultados para 3-MCPD com valores médios entre 203 a 1205 µg/kg. Para o Glicidol os valores foram de 2 a 1198 µg/kg, com elevado o desvio padrão entre os resultados analíticos, onde o óleo de palma apresentou a maior variação de 1600 a 5260 µg/kg. Através da avaliação do risco realizada para o composto 3-MCPD foi possível detectar, utilizando o critério do pior cenário de exposição e resultados analíticos, os valores diários de consumo de óleo de algodão de 0,044 µg/kg p.c., de óleo de girassol 0,045 µg/kg p.c., óleo de canola 0,18 µg/kg p.c., óleo de palma de 0,28 µg/p.c, óleo de milho de 0,0462 µg/kg p.c., e o óleo de soja, de maior consumo no Brasil (72%) apresentou o valor de 0,27 µg/kg p.c. O consumo de todos estes óleos, pela a população brasileira, pode ser considerado seguro ao comparar com o valor de TDI Ingestão Diária Tolerável - de 2µg/kg p.c.. Através da avaliação do risco realizada também utilizando o critério de pior cenário de exposição e e resultados analíticos para o composto glicidol foi possível verificar que os valores diários de consumo de óleo de algodão de 0,061 µg/kg p.c., de óleo de girassol 0,03 µg/kg p.c., óleo de canola 0,13 µg/kg p.c. e de óleo de palma de 0,57 µg/p.c, de óleo de milho de 0,11 µg/kg p.c, e o óleo de soja de maior consumo no Brasil (72%) não ultrapassam o valor de 0,288 µg/kg p.c indicando consumo seguro destes óleos para a população brasileira baseado na TDI de 1000µg/kg p.c


Chloropropanols are a known group of contaminants related to food processing. They are formed during the reaction process between lipids and chlorides when submitted to heat treatment and can be found in free or bound form. The 3-monochloro-1,2-propanediol (3-MCPD), is classified by IARC as a possible human carcinogen (group 2B). Glycidol (and its esters), also classified by IARC as a substance likely to be carcinogenic to humans (group 2A), has recently been found in food. The present study aims to evaluate the presence of 3-MCPD and glycidol in edible vegetable oils using gas chromatography with triple quadrupole MS/MS mass detector. The technique applied is recommended by AOCS, guide Cd 29c-13, an indirect analysis, and allows quantification of 3-MCPD and glycidol by building the calibration curves and analysis of reference samples. The method was validated and the detection limit of the contaminant 3-MCPD of 42,4 µg/kg and the quantification limit of 50 µg/kg was established. For Glycidol the detection limit of was 43,5 µg/kg and quantification limit was 50 µg/kg. The results obtained in the calibration and linearity curves demonstrated that the method could express results with good linearity (0 10 mg/kg, r2, = 0.9991). The results obtained in the trueness trials agreed to the criteria of 70 to 120% of recovery, and ± 20% of variation between the results according to what is preconized by SANTE (2017). The method showed to be selective, since no interfering peaks were observed in the retention times of the studied compounds. The tests performed on low, medium and high values demonstrated the robustness and precision of the method, so the validation was considered completed and suitable for the purpose. A total of 368 vegetable oil samples were analyzed (76 samples of canola oil, 48 samples of corn oil, 69 samples of cottonseed oil, 33 samples of palm oil, 10 samples of kern palm oil, 50 samples of palm olein, 30 samples of soybean oil and 51 samples of sunflower oil). The results found in samples for 3-MCPD were within mean values between 203 and 1205 µg/kg. The results found in samples for glycidol were within mean values between 2 to 1198 µg/kg where palm oil presented the highest variation for glycidol from 1600 to 5260 µg/kg. Through the risk assessment for the contaminant 3-MCPD it was possible to detect the values based on exposed worst case scenario and analytical results. The results for cottom oil were 0,044 µg/kg bw, sunflower 0,045 µg/kg bw, canola 0,18 µg/kg bw and palm oil 0,28 µg/kg bw, corn oil 0,0462 µg/kg bw, and for soybean, which is the most consumed oil in Brazil (72%) the value of 0,27 µg/kg bw. These results indicates safe consumption for these oils based in the Theoretical Daily Ingestion - TDI of 2µg/kg bw. The risk assessment for the glycidol based on exposure worst case scenario and analytical results presented for cottom oil the value of 0,061 µg/kg bw, sunflower 0,03 µg/kg bw, canola oil 0,13 µg/kg bw , palm oil 0,57 µg/kg bw, corn oil 0,11 µg/kg bw and for soybean, which is the most consumed in Brazil - 72% the value of 0,27 µg/kg bw. These results indicates safe consumption for these oils based in the TDI of 1000µg/kg bw


Subject(s)
Oils/analysis , alpha-Chlorohydrin/analysis , Mass Spectrometry/methods , Food Contamination/prevention & control , Risk Assessment , Gas Chromatography-Mass Spectrometry/methods
9.
São Paulo; s.n; s.n; 2019. 139 p. graf, tab, ilus.
Thesis in Portuguese | LILACS | ID: biblio-1007438

ABSTRACT

A sinalização da matriz extracelular (MEC) é essencial para a determinação do destino e comportamento de células epiteliais da glândula mamária. Entretanto, pouco é conhecido sobre os mecanismos moleculares envolvidos nesse processo. A via Hippo, uma cascata de sinalização que participa da regulação de diversos comportamentos celulares, incluindo o tamanho de órgãos, parece ser uma importante candidata a mediadora sinalização da MEC. Resultados preliminares do laboratório indicam que a arquitetura tecidual e a membrana basal, componente da MEC de epitélios e outros tecidos, influenciam a localização, concentração e atividade de YAP, uma proteína efetora da via Hippo, em células epiteliais mamárias. Neste contexto, o objetivo deste trabalho foi identificar as proteínas que interagem com Yap (ortólogo de YAP em camundongo) nas células epiteliais da glândula mamária em resposta à membrana basal. Foram utilizadas células EpH4, uma linhagem mamária não-tumoral murina, como modelo de diferenciação funcional e formação de ácinos em um ensaio de cultura tridimensional (3D). O tratamento de estruturas multicelulares 3D pré-formadas em placas nãoadesiva com uma matriz rica em laminina (lrECM) alterou a localização e o padrão subcelular de Yap, assim como a expressão gênica de membros da via Hippo e dos alvos de Yap, mas não alterou a expressão das proteínas da via em nível de proteína. O ensaio de co-imunoprecipitação (CoIP) seguida de análise por espectrometria de massas identificou um conjunto diferencial de proteínas que interagem com Yap na fração citoplasmática de células EpH4 cultivadas na ausência ou na presença de lrECM em um modelo de ECM-overlay. Uma análise realizada junto à database KEGG Pathways revelou que os possíveis interagentes Yap nas células cultivadas não-tratadas com lrECM participam de processos relacionados à proteólise mediada por ubiquitina, enquanto nas células expostas à lrECM os possíveis interagentes estão associados a processos metabólicos e são especialmente proteínas-chave do metabolismo de lipídios. A busca na plataforma de redes de interação STRING não identificou trabalhos que destaquem a interação de Yap com estas proteínas. A plataforma Vizit indica a participação de Yap em processos relacionados à síntese e atividade de lipídios e hormônios, o que reforça as evidências de que está pode ser uma nova função de Yap ainda não explorada em detalhes. A fim de se obter resultados complementares à CoIP, padronizamos o ensaio de identificação por biotinilação dependente de proximidade (BioID) em células embrionárias de rim humano da linhagem 293FT. As proteínas isoladas por pulldown foram identificadas por espectrometria de massas e uma análise junto à database Gene Ontology indicou que os possíveis interagentes de Yap nestas células são em sua maioria proteínas relacionadas à via Hippo, o que reforça a robustez do ensaio. Nós pretendemos transpor este sistema para as células EpH4. A expectativa é que, em conjunto, estes resultados nos orientem em projetos futuros para compreender os mecanismos de sinalização da MEC na morfogênese e diferenciação da glândula mamária


Extracellular matrix (ECM)-signaling is crucial for determination of epithelial cell fate and behavior in the mammary gland. However, little is known about the molecular mechanisms involved in these processes. The Hippo pathway, a signaling cascade involved in the regulation of several cellular processes, including organ size, seems to be an important candidate as a mediator of this signaling. Our preliminary results indicate that the tissue architecture and the basement membrane, an ECM component of epithelia and other tissues, influence the location, level and activity of YAP, an effector of the Hippo pathway. In this context, the goal of this work was to identify the proteins that interact with Yap (ortholog of YAP in mouse) in mammary epithelial cells in response to the basement membrane. We used EpH4 cells, a nontumoral murine mammary cell, in a functional differentiation and acini-forming in tridimensional (3D) culture assay. Treatment of 3D multicellular structures pre-formed on nonadhesive plates with a laminin-rich extracellular matrix (lrECM) altered the subcellular localization and pattern of Yap, as well as gene expression of Hippo pathway proteins and Yap targets, but did not altered the expression of the pathway members at the protein level. Coimmunoprecipitation (CoIP) followed by mass spectrometry analysis identified a differential set of proteins interacting with Yap in cytoplasmic fractions of EpH4 cells in the absence or presence of lrECM in an ECM-overlay culture model. An analysis performed with the KEGG Pathways database revealed that putative Yap interactors in non-treated cells participate in processes related to ubiquitin-mediated proteolysis, whereas in cells exposed to lrECM Yap interactors are associated to metabolic processes and are mainly key-proteins of metabolism of lipids and carbohydrates. A search in interaction networks platform STRING did not identify previous works that showing the interaction of Yap with these proteins. Vizit platform indicated the participation of Yap in processes related to the synthesis and activity of lipids and hormones, which reinforces the evidences that Yap can play a novel poorly explored role. To obtain complementary results to CoIP, we devised the proximity-dependent biotinylation identification (BioID) assay on embryonic renal cells of 293FT cell line. Pulldown-isolated proteins were identified by mass spectrometry and an analysis performed with Gene Ontology database revealed that putative Yap interactors are Hippo pathway-related proteins, which reinforces the robustness of the assay. We intend to transpose this system to the EpH4 cells. We expect that, together, these results will guide us in future projects to understand the signaling mechanisms of ECM in mammary gland morphogenesis and differentiation


Subject(s)
Animals , Male , Female , Mammary Glands, Human , Epithelial Cells/classification , Extracellular Matrix/chemistry , Mass Spectrometry/methods , Basement Membrane/anatomy & histology , Laminin/adverse effects
10.
São Paulo; s.n; s.n; 2019. 93 p. tab, ilus, graf.
Thesis in Portuguese, French | LILACS | ID: biblio-1025676

ABSTRACT

Os aldeídos são espécies reativas que podem ser produzidos endogenamente por processos como a lipoperoxidação, podendo reagir com lipídios, proteínas e DNA. Diversas evidências apontam para o envolvimento de aldeídos reativos na progressão de patologias como doenças cardiovasculares, arteriosclerose e doenças neurodegenerativas. Uma meta central do CEPIDRedoxoma é estudar a reatividade química de intermediários redox em ambientes biológicos e consequentes mudanças na estrutura e função de biomoléculas, entender como cada intermediário redox reage com biomoléculas específicas e os efeitos resultantes, essenciais para a concepção de biomarcadores e antioxidantes. O nosso grupo estuda os mecanismos de formação, detoxificação e reação com biomoléculas de aldeídos reativos endógenos e exógenos e seu papel em patologias como a esclerose lateral amiotrófica (ALS). Um dos mecanismos de detoxificação desses aldeídos é através da conjugação com a carnosina. Recentemente, foi observado que a suplementação de animais transgênicos ALS SOD G93A com carnosina via oral resultou em retardo da perda de peso e tendência de aumento da sobrevida dos animais. O presente projeto buscou investigar o possível papel da carnosina em animais modelo para ALS. Para isso as modificações em DNA induzidas por aldeídos reativos e a formação de adutos de carnosina-aldeídos foram analisadas através de metodologia HPLC-MS/MS. Assim observamos que ratos suplementados com carnosina apresentaram níveis significativamente menores de proteína carbonilada em músculo e fígado. Em fígadoforam vistos níveis menores de dois adutos de DNA, 8-oxodGuo e1,N2-HO-propanodGuo, em animais suplementados. Em cérebro foram detectados níveis menores de 1, N2-εdGuo. Com relação aos adutos carnosina-aldeídos, foi observado níveis significativamente maiores do aduto CAR-HHE na medula. Com embasamento nos resultados aqui apresentados, sugere-se a utilização de sequestradores de aldeídos como uma estratégia terapêutica em condições fisiopatológicas nas quais ao acúmulo dessas espécies está comprovado


Aldehydes are reactive species that can be produced endogenously by processes such as lipid peroxidation, which can react with lipids, proteins and DNA. Several evidences point to the involvement of reactive aldehydes in the progression of pathologies such as cardiovascular diseases, atherosclerosis and neurodegenerative diseases. A central goal of CEPID-Redoxoma is to study the chemical reactivity of redox intermediates in biological environments and consequent changes in the structure and function of biomolecules, to understand how each redox intermediate reacts with specific biomolecules and the resulting effects, essential for the design of biomarkers and antioxidants. Our group studies the mechanisms of formation, detoxification and reaction with biomolecules of endogenous and exogenous reactive aldehydes and their role in pathologies such as amyotrophic lateral sclerosis (ALS). One of the detoxification mechanisms of these aldehydes is through carnosine conjugation. Recently, we observed that oral carnosine supplementation in transgenic ALS SODG93A animals resulted in delayed weight loss and a tendency to increase the survival of the animals. The present project investigated the potential role of carnosine in animal models for ALS. Thus, reactive aldehydes induced DNA modifications and carnosine aldehyde adducts were analyzed by HPLC-MS/MS. We observed that rats supplemented with carnosine presented significantly lower levels of protein carbonylation in muscle and liver. Lower levels of two DNA adducts, 8-oxodGuo and 1, N2-HO-propanodGuo, were observed in liver of the supplemented animals. Lower levels of 1, N2-εdGuo were detected in the brain. Regarding the carnosine-aldehydeadducts, significantly higher levels of the CAR-HHE adduct were observed in spinal cord. The results presented here suggest the use of aldehyde scavengers as a therapeutic strategy under pathological conditions in which is proven the accumulation of these species


Subject(s)
Animals , Male , Female , Rats , Biological Phenomena , Carnosine/adverse effects , Aldehydes/analysis , Amyotrophic Lateral Sclerosis/pathology , Mass Spectrometry/methods , Chromatography, Liquid/methods , DNA Adducts
11.
Braz. J. Pharm. Sci. (Online) ; 55: e17249, 2019. tab, graf
Article in English | LILACS | ID: biblio-1055327

ABSTRACT

In the present study we reported the antimicrobial activity of actinomycetes isolated from aridic soil sample collected in Karoo, South Africa. Eighty-six actinomycete strains were isolated and purified, out of them thirty-four morphologically different strains were tested for antimicrobial activity. Among 35 isolates, 10 (28.57%) showed both antibacterial and antifungal activity. The ethyl acetate extract of strain KRG-1 showed the strongest antimicrobial activity and therefore was selected for further investigation. The almost complete nucleotide sequence of the 16S rRNA gene as well as distinctive matrix-assisted laser desorption/ionization-time-of-flight/mass spectrometry (MALDI-TOF/MS) profile of whole-cell proteins acquired for strain KRG-1 led to the identification of Streptomyces antibioticus KRG-1 (GenBank accession number: KX827270). The ethyl acetate extract of KRG-1 was fractionated by HPLC method against the most suppressed bacterium Staphylococcus aureus (Newman). LC//MS analysis led to the identification of the active peak that exhibited UV-VIS maxima at 442 nm and the ESI-HRMS spectrum showing the prominent ion clusters for [M-H2O+H]+ at m/z 635.3109 and for [M+Na]+ at m/z 1269.6148. This information could be assigned to chromopeptide lactone antibiotic - actinomycin. Our results suggest that unexplored soils could be an interesting source for exploring antibacterial secondary metabolites.


Subject(s)
Soil , Actinobacteria/classification , Dactinomycin/analysis , Mass Spectrometry/methods , Streptomyces antibioticus , RNA, Ribosomal, 16S , Chromatography, High Pressure Liquid/methods , Methods
12.
Braz. oral res. (Online) ; 33: e043, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001605

ABSTRACT

Abstract: Proteomic techniques have become popular in medicine and dentistry because of their widespread use in analyzing bodily fluids such as blood, saliva, urine, and gingival crevicular fluids as well as hard tissues such as enamel, dentine, and cementum. This review is a guide to proteomic techniques in general dentistry, summarizing techniques and their clinical application in understanding and diagnosing diseases and their use in identifying biomarkers of various diseases.


Subject(s)
Humans , Saliva/chemistry , Sjogren's Syndrome/diagnosis , Proteome , Proteomics/methods , Salivary Proteins and Peptides/chemistry , Mass Spectrometry/methods , Mouth Neoplasms/diagnosis , Biomarkers/chemistry , Electrophoresis, Polyacrylamide Gel
13.
J. venom. anim. toxins incl. trop. dis ; 25: e147418, 2019. graf, ilus
Article in English | LILACS | ID: biblio-984697

ABSTRACT

Background: Pore-forming proteins (PFP) are a class of toxins abundant in the venom of sea anemones. Owing to their ability to recognize and permeabilize cell membranes, pore-forming proteins have medical potential in cancer therapy or as biosensors. In the present study, we showed the partial purification and sequencing of a pore-forming protein from Anthopleura dowii Verrill (1869). 17. Methods: Cytolytic activity of A. dowii Verrill (1869) venom was determined via hemolysis assay in the erythrocytes of four mammals (sheep, goat, human and rabbit). The cytotoxic activity was analyzed in the human adherent lung carcinoma epithelial cells (A549) by the cytosolic lactate dehydrogenase (LDH) assay, and trypan blue staining. The venom was fractionated via ammonium sulfate precipitation gradient, dialysis, and ion exchange chromatography. The presence of a pore-forming protein in purified fractions was evaluated through hemolytic and cytotoxic assays, and the activity fraction was analyzed using the percent of osmotic protections after polyethylene glycol (PEG) treatment and mass spectrometry. 18. Results: The amount of protein at which the venom produced 50% hemolysis (HU50) was determined in hemolysis assays using erythrocytes from sheep (HU50 = 10.7 ± 0.2 µg), goat (HU50 = 13.2 ± 0.3 µg), rabbit (HU50 = 34.7 ± 0.5 µg), and human (HU50 = 25.6 ± 0.6 µg). The venom presented a cytotoxic effect in A549 cells and the protein amount present in the venom responsible for producing 50% death (IC50) was determined using a trypan blue cytotoxicity assay (1.84 ± 0.40 µg/mL). The loss of membrane integrity in the A549 cells caused by the venom was detected by the release of LDH in proportion to the amount of protein. The venom was fractionated; and the fraction with hemolytic and cytotoxic activities was analyzed by mass spectrometry. A pore-forming protein was identified. The cytotoxicity in the A549 cells produced by the fraction containing the pore-forming protein was osmotically protected by PEG-3350 Da molecular mass, which corroborated that the loss of integrity in the plasma membrane was produced via pore formation. 19. Conclusion: A. dowii Verrill (1869) venom contains a pore-forming protein suitable for designing new drugs for cancer therapy.(AU)


Subject(s)
Humans , Animals , Sea Anemones , Cnidarian Venoms/isolation & purification , Lung Neoplasms/therapy , Poisons/toxicity , Mass Spectrometry/methods , A549 Cells
14.
Bol. latinoam. Caribe plantas med. aromát ; 17(4): 381-393, jul. 2018. ilus, tab
Article in English | LILACS | ID: biblio-915662

ABSTRACT

This study analysed the total content of phenolic compounds in roots and rhizomes extracts from two populations of Valeriana carnosa Sm. (Caprifoliaceae) at three phenological stages. Total phenolic content was determined through the Folin-Ciocalteu method, which ranged between individuals from 3.56 to 11.68 mg GAE/g of dry sample. Antioxidant activity was determined using the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), which showed a significant positive correlation between antioxidant activity and total phenolic content. We tentatively identified 18 phenolic compounds by HPLC-MS, mostly phenolic acids, one of which was present only in the Hoya population at the vegetative stage and one only in the Piltri population at the flowering and fruiting stages. Phenolic compounds in subterranean organs of V. carnosa vary qualitatively (between populations/stages) and quantitatively at intra- and inter-population level at different phenological stages. In both populations, on average a higher phenolic content and antioxidant activity were recorded at the flowering and fruiting stages.


En este estudio se analizó el contenido total de compuestos fenólicos en extractos de raíces y rizomas provenientes de dos poblaciones de Valeriana carnosa Sm. (Caprifoliaceae) en tres estadios fenológicos. El contenido total de fenoles se determinó sobre muestras secas, mediante el método de Folin-Ciocalteu, que varió de 3.56-11.68 mg GAE/g entre individuos. Se determinó la actividad antioxidante utilizando el radical estable 2,2-difenil-1-picrilhidrazilo (DPPH) y se observó una correlación positiva significativa entre la actividad antioxidante y el contenido total de fenoles. Identificamos tentativamente 18 compuestos fenólicos mediante HPLC-MS, principalmente ácidos fenólicos, dos de los cuales estuvieron presentes en la población Hoya en la etapa vegetativa y en la población Piltri en las etapas de floración y fructificación. Los compuestos fenólicos en órganos subterráneos de V. carnosa varían cualitativamente (entre poblaciones/estadios) y cuantitativamente a nivel intra- e inter-poblacional en diferentes estadios fenológicos. En ambas poblaciones, en promedio se registró un mayor contenido de fenoles y actividad antioxidante en las etapas de floración y fructificación.


Subject(s)
Phenols/analysis , Valerian/chemistry , Plant Extracts/chemistry , Antioxidants/chemistry , Mass Spectrometry/methods , Plant Extracts/pharmacology , Free Radical Scavengers , Chromatography, High Pressure Liquid/methods , Plant Roots/chemistry , Antioxidants/pharmacology
15.
Rev. argent. endocrinol. metab ; 55(1): 43-56, mar. 2018. graf.
Article in Spanish | LILACS | ID: biblio-1248114

ABSTRACT

Esta revisión fue realizada con el fin de evaluar nuestros resultados de laboratorio así como aquellos de la literatura que constituyen, a nuestro entender, aportes significativos en el síndrome de ovarios poliquísticos (SOP). Nuestro especial énfasis será presentar las limitaciones de las metodologías empleadas por nuestro grupo, comparativamente a las reportadas por otros investigadores. La determinación de andrógenos, en particular de Testosterona (TT), es quizá la de mayor complejidad dado que los resultados con los diferentes inmunoensayos empleados en nuestro medio producen resultados muy variables por los diferentes métodos y aún entre laboratorios que usan la misma metodología. La técnica de referencia es la cromatografía líquida en tándem con espectrometría de masa (LC-MSMS), de difícil aplicación en laboratorios de análisis clínicos debido a su alto costo y la imposibilidad de resolver numerosas muestras. En estudios previos demostramos que de los métodos habitualmente usados para evaluar la TT circulante, solo en 2 inmunoensayos los resultados obtenidos fueron satisfactoriamente validados indirectamente según el criterio del Consenso de los Centros para el Control y Prevención de Enfermedades (CDC, USA) contra LC-MSMS, los cuales fueron comparables a dicha metodología con niveles superiores a 0,5 ng/ml. El SOP puede presentar factores de riesgo aumentados para la enfermedad cardiovascular y la diabetes II. Estos factores no están debidamente categorizados en función de los distintos fenotipos del SOP. Se evaluarán los principales analitos empleados con este objetivo y los nuevos que aporten elementos de mayor especificidad en este sentido


This review was performed in order to evaluate our laboratory results as well as those of the literature that constitute, in our opinion, significant contributions in these pathophysiologies. Our special emphasis will be on presenting the limitations of the methodologies used by our group, compared to those reported by other researchers. The determination of androgens, in particular Testosterone (TT), is perhaps the most complex since the results with the different immunoassays used in our environment produce very variable results by the different methods and even between laboratories that use the same methodology. The reference technique is LC-MSMS, difficult to apply in clinical analysis laboratories because of its high cost and the inability to solve numerous samples. In previous studies, we demonstrated that, in comparison to LC-MSMS with the usual methods for evaluating circulating TT, the results obtained in only 2 immunoassays were satisfactorily validated indirectly according to the criteria of CDC against LC-MSMS, which were comparable to that methodology with levels higher than 0.5 ng/ml. PCOS may have increased risk factors for cardiovascular disease and diabetes II. These factors are not properly categorized according to the different phenotypes of PCOS. The main analytes used for this purpose will be evaluated and new ones that contribute elements of greater specificity in this sense


Subject(s)
Humans , Female , Polycystic Ovary Syndrome/etiology , Polycystic Ovary Syndrome/physiopathology , Testosterone/analysis , Phenotype , Mass Spectrometry/methods , Immunoassay/methods , Chromatography, Liquid/methods
16.
São Paulo; s.n; s.n; 2018. 130 p. graf, tab, ilus.
Thesis in Portuguese | LILACS | ID: biblio-998555

ABSTRACT

A microextração por sorbente empacotado (MEPS) é uma técnica de preparo de amostras ainda pouco utilizada no âmbito da toxicologia, em que os mesmos princípios da extração em fase sólida convencional são adaptados para uma escala miniaturizada. As principais vantagens da técnica estão associadas ao pequeno volume de amostra e de solventes utilizados, à possibilidade de realizar múltiplas extrações com um mesmo cartucho e à facilidade de automação. Os benzodiazepínicos possuem grande relevância na toxicologia dada sua ampla utilização e seus efeitos que podem, por exemplo, comprometer a capacidade de dirigir, além do uso abusivo, e como drogas facilitadoras de crimes. Neste trabalho, um método de MEPS foi desenvolvido e otimizado para a determinação de sete benzodiazepínicos e seus produtos de biotransformação (diazepam, clonazepam, flunitrazepam, alprazolam, bromazepam, 7-aminoflunitrazepam e nordiazepam) utilizando 100 µL de amostra de sangue total post mortem. Após a extração, os eluatos foram analisados por cromatografia líquida em fase reversa acoplada a espectrometria de massas. O método foi validado de acordo com as recomendações do Scientific Working Group for Forensic Toxicology, apresentando linearidade adequada de 5 a 500 ng.mL-1 . Os valores de exatidão (90,4 a 109,5%), precisão intra-dia (2,5 a 10,7 %CV) e inter-dia (1,1 a 8,0 %CV) também foram satisfatórios. MEPS foi realizada mais de 60 vezes com a mesma fase extratora sem evidências de contaminação cruzada. Dez amostras reais fornecidas pelo Instituto Médico Legal de São Paulo foram analisadas. Foram quantificados diazepam, nordiazepam, clonazepam e bromazepam. Os resultados encontrados em cada uma das amostras foram comparados com dados da literatura


Microextraction by packed sorbent (MEPS) is a sample preparation technique still little used in toxicology, where the same principles of conventional solid phase extraction are adapted to a miniaturized scale. The main advantages of the technique are associated with the small volume of sample and solvents required, the possibility of performing multiple extractions with the same cartridge and ease process automation. Benzodiazepine drugs are relevant in toxicology because of their widespread use, and effects (which may, for example, compromise the ability to drive vehicles), abuse and records as crime-facilitating drugs. In this work, a MEPS method was developed and optimized for a determination of seven benzodiazepines and their metabolites (diazepam, nordiazepam, clonazepam, flunitrazepam, 7-aminoflunitrazepam, alprazolam, and bromazepam) using 100 µL of post mortem whole blood. After extraction, the eluates were analyzed by reversed-phase liquid chromatography coupled to mass spectrometry. The method was validated according to the recommendations of the Scientific Working Group for Forensic Toxicology, presenting adequate linearity from 5 to 500 ng.mL-1 . The values of accuracy (90.4 to 109.5%), intra-day precision (2.5 to 10.7 %CV) and inter-day (1.1 to 8.0 %CV) also presented satisfactory results. MEPS was performed more than 60 times with the same extractive phase without compromising the results with the evidence of carryover. Institute of Legal Medicine were submitted to analysis by MEPS-LC-MS/MS. In these samples, the following analytes were quantified: diazepam, nordiazepam, clonazepam and bromazepam. The results found in each of the samples were compared with data from the literature


Subject(s)
Benzodiazepines/analysis , Solid Phase Microextraction/instrumentation , Mass Spectrometry/methods , Autopsy , Computer Simulation/statistics & numerical data , Biotransformation , Chromatography, Liquid/methods , Drug Samples , Forensic Toxicology/classification
17.
Article in English | LILACS | ID: biblio-894164

ABSTRACT

Wasp venoms constitute a molecular reservoir of new pharmacological substances such as peptides and proteins, biological property holders, many of which are yet to be identified. Exploring these sources may lead to the discovery of molecules hitherto unknown. This study describes, for the first time in hymenopteran venoms, the identification of an enzymatically inactive phospholipase A2 (PLA2) from the venom of the social wasp Polybia occidentalis. Methods: P. occidentalis venom was fractioned by molecular exclusion and reverse phase chromatography. For the biochemical characterization of the protein, 1D and 2D SDS-PAGE were performed, along with phospholipase activity assays on synthetic substrates, MALDI-TOF mass spectrometry and sequencing by Edman degradation. Results: The protein, called PocTX, was isolated using two chromatographic steps. Based on the phospholipase activity assay, electrophoresis and mass spectrometry, the protein presented a high degree of purity, with a mass of 13,896. 47 Da and a basic pI. After sequencing by the Edman degradation method, it was found that the protein showed a high identity with snake venom PLA2 homologues. Conclusion: This is the first report of an enzymatically inactive PLA2 isolated from wasp venom, similar to snake PLA2 homologues.(AU)


Subject(s)
Animals , Wasps , Receptors, Phospholipase A2/isolation & purification , Receptors, Phospholipase A2/chemistry , Poisoning , Mass Spectrometry/methods , Receptors, Phospholipase A2/chemistry , Chromatography, Reverse-Phase/methods
18.
São Paulo; s.n; s.n; 2018. 93 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-881085

ABSTRACT

A esporotricose é uma doença crônica que envolve o tecido subcutâneo afetando seres humanos e animais, causada pelo fungo termodimórfico Sporothrix spp.. A esporotricose é endêmica na América latina, principalmente no Brasil que teve o maior surto zoonótico já registrado, ocorrendo na cidade do Rio de Janeiro. A espécie Sporothrix brasiliensis é a mais diagnosticada no surto e a mais virulenta entre as especies de Sporothrix spp., causando formas mais graves da doença. A esporotricose em gatos é endêmica, fatal e um dos principais fatores pelo alto número de casos no Rio de Janeiro. O tratamento é longo e não vem sendo o suficiente para conter o número de casos da doença. Uma vacina contra a esporotricose poderia mudar esse paradigma no Brasil. O presente trabalho obteve o proteoma da cepa S. brasiliensis 5110 por meio de uma eletroforese 2D, e caracterizou e identificou as possíveis proteínas imunogênicas do fungo por espectrometria de massa. Por meio de programas de predição, foi avaliado e sintetizado 7 sequências de aminoácidos,das proteínas identificadas com maiores chances de se acoplar a molécula MHC de classe II. Apenas 3 foram capazes de induzir proliferação in vitro, os peptídeos ZR3, ZR4 e ZR8, que foram utilizados como vacina na esporotricose subcutânea e avaliados sua eficácia por meio da carga fúngica, diâmetro das lesões, perfil celular e níveis de citocinas. Neste trabalho concluímos que o peptídeo ZR8 foi o melhor candidato à vacina na esporotricose, pois foi capaz de diminuir o diâmetro das lesões, aumentar os níveis de citocinas protetoras (IFN-γ, IL-17A e IL-1ß) e aumentar o número de células TCD4+ e CD3-/CD19+, sendo assim induzindo uma resposta imunológica protetora na esporotricose subcutânea


Sporotrichosis is a chronic disease, which involves the subcutaneous tissue affecting humans and animals caused by the thermodymorphic fungus Sporothrix spp. Sporotrichosis is endemic in Latin America, mainly in Brazil that had the largest zoonotic outbreak ever recorded, occurring in the city of Rio de Janeiro. The Sporothrix brasiliensis is the species more diagnosed in the outbreak and most virulent, causing severe forms of the disease. Sporotrichosis in cats is endemic, fatal and the main factors due to the high number of cases of the disease in Rio de Janeiro. The treatment is long, and has not been enough to contain the number of cases of sporotrichosis. A vaccine against sporotrichosis could change this paradigm in Brazil. The present work obtained the proteome of S. brasiliensis 5110 strain by 2D electrophoresis, and characterized and identified possible immunogenic proteins by mass spectrometry. By prediction programs were evaluated and synthesized 7 peptide sequence from antigenic proteins that have the highest chances of coupling to the MHC class II molecule. From these 7 peptides only 3 were able to induce proliferation in vitro, called ZR3, ZR4 and ZR8 peptides, that were used as a vaccine in subcutaneous sporotrichosis and evaluated their efficacy through fungal load, lesion diameter, cell profile and cytokine levels. We conclude that ZR8 peptide was the best candidate for sporotrichosis vaccine, since it was able to decrease the lesion diameter, increase the levels of protective cytokines (IFN-γ, IL-17A and IL-1ß) and increase the number of CD4+ T cells and CD3-/CD19+ inducing a protective immune response in subcutaneous sporotrichosis


Subject(s)
Animals , Male , Female , Mice , Sporothrix/classification , Blotting, Western/methods , Forecasting/methods , Mass Spectrometry/methods , Proteome/pharmacology , Sporotrichosis/complications , Statistical Analysis , Vaccines/analysis
19.
São Paulo; s.n; s.n; 2018. 93 p. tab, ilus, graf.
Thesis in Portuguese | LILACS | ID: biblio-905908

ABSTRACT

A esporotricose é uma doença crônica que envolve o tecido subcutâneo afetando seres humanos e animais, causada pelo fungo termodimórfico Sporothrix spp.. A esporotricose é endêmica na América latina, principalmente no Brasil que teve o maior surto zoonótico já registrado, ocorrendo na cidade do Rio de Janeiro. A espécie Sporothrix brasiliensis é a mais diagnosticada no surto e a mais virulenta entre as especies de Sporothrix spp., causando formas mais graves da doença. A esporotricose em gatos é endêmica, fatal e um dos principais fatores pelo alto número de casos no Rio de Janeiro. O tratamento é longo e não vem sendo o suficiente para conter o número de casos da doença. Uma vacina contra a esporotricose poderia mudar esse paradigma no Brasil. O presente trabalho obteve o proteoma da cepa S. brasiliensis 5110 por meio de uma eletroforese 2D, e caracterizou e identificou as possíveis proteínas imunogênicas do fungo por espectrometria de massa. Por meio de programas de predição, foi avaliado e sintetizado 7 sequências de aminoácidos,das proteínas identificadas com maiores chances de se acoplar a molécula MHC de classe II. Apenas 3 foram capazes de induzir proliferação in vitro, os peptídeos ZR3, ZR4 e ZR8, que foram utilizados como vacina na esporotricose subcutânea e avaliados sua eficácia por meio da carga fúngica, diâmetro das lesões, perfil celular e níveis de citocinas. Neste trabalho concluímos que o peptídeo ZR8 foi o melhor candidato à vacina na esporotricose, pois foi capaz de diminuir o diâmetro das lesões, aumentar os níveis de citocinas protetoras (IFN-γ, IL-17A e IL-1ß) e aumentar o número de células TCD4+ e CD3-/CD19+, sendo assim induzindo uma resposta imunológica protetora na esporotricose subcutânea


Sporotrichosis is a chronic disease, which involves the subcutaneous tissue affecting humans and animals caused by the thermodymorphic fungus Sporothrix spp. Sporotrichosis is endemic in Latin America, mainly in Brazil that had the largest zoonotic outbreak ever recorded, occurring in the city of Rio de Janeiro. The Sporothrix brasiliensis is the species more diagnosed in the outbreak and most virulent, causing severe forms of the disease. Sporotrichosis in cats is endemic, fatal and the main factors due to the high number of cases of the disease in Rio de Janeiro. The treatment is long, and has not been enough to contain the number of cases of sporotrichosis. A vaccine against sporotrichosis could change this paradigm in Brazil. The present work obtained the proteome of S. brasiliensis 5110 strain by 2D electrophoresis, and characterized and identified possible immunogenic proteins by mass spectrometry. By prediction programs were evaluated and synthesized 7 peptide sequence from antigenic proteins that have the highest chances of coupling to the MHC class II molecule. From these 7 peptides only 3 were able to induce proliferation in vitro, called ZR3, ZR4 and ZR8 peptides, that were used as a vaccine in subcutaneous sporotrichosis and evaluated their efficacy through fungal load, lesion diameter, cell profile and cytokine levels. We conclude that ZR8 peptide was the best candidate for sporotrichosis vaccine, since it was able to decrease the lesion diameter, increase the levels of protective cytokines (IFN-γ, IL-17A and IL-1ß) and increase the number of CD4+ T cells and CD3-/CD19+ inducing a protective immune response in subcutaneous sporotrichosis


Subject(s)
Animals , Female , Mice , Peptides , Sporothrix/growth & development , Vaccines/analysis , Electrophoresis/instrumentation , Mass Spectrometry/methods , Mycoses , Proteome , Sporotrichosis/prevention & control
20.
São Paulo; s.n; s.n; 2018. 117 p. tab, graf.
Thesis in English | LILACS | ID: biblio-909537

ABSTRACT

Lipids encompass a wide range of hydrophobic molecules present in cells. The molecular characteristics of lipids determine their cellular localization and biological function. In general, lipids are regarded as essential components of membranes, as energy reservoir and modulators of signaling pathways linked to cellular metabolism and survival, among others. In mammals, a large part of the lipids are esterified to polyunsaturated fatty acids (PUFAs), especially docosahexaenoic (DHA) and arachidonic (ARA) acids, essential for several physiological processes, including normal brain development. However, PUFAs are very susceptible to oxidation by reactive oxygen species (ROS) generated endogenously. Once oxidized, lipids are able to modify thiol groups of peptides and proteins leading to modulation of signaling pathways and cellular redox balance. In the chapter 1, we investigated the mechanisms involved in modification of thiol groups of peptides and protein by autoxidation products derived from PUFAs. Here, we identified several glutathione (GSH) adducts covalently modified by hydroxy-endoperoxides derived from both DHA and ARA. Detailed inspection of MS/MS spectra of GSH-adducts revealed that GSH and hydroxy-endoperoxides are likely bonded through a sulfur-oxygen chemical bond in a reaction which involves a nucleophilic attack by the thiolate anion. Also, we suggest that the efficiency of modification of thiol by hydroxy-endoperoxides are also dependent of the thiol reactivity, as demonstrated by covalent modification of the most reactive cysteine residue (Cys111) of the antioxidant enzyme Cu,Zn-superoxide dismutase (SOD1). Chemical modifications of thiol groups by hydroxy-endoperoxides may modulate protein aggregation and cellular redox status, yieldingGSH adducts capable to modulate inflammation, as reported for the enzymatically generated counterparts. In the chapter 2, we investigated the role of lipids in amyotrophic lateral sclerosis (ALS), since inflammation and oxidative stress in motor neurons are hallmarks of this neurodegenerative disease. Using an untargeted lipidomics approach based on mass spectrometry coupled to liquid chromatography (UHPLC-MS/MS), we investigated the lipid metabolism in motor cortex and spinal cord tissues of a rodent model of ALS. Analysis of the motor cortex showed that the main lipid alterations were age-dependent and linked to metabolism of sphingolipids. In contrast, the major lipid alterations in the spinal cord were found in ALS symptomatic group, being the metabolism of ceramides, cholesteryl esters and cardiolipin the most affected. According to our findings and data reported in the literature, we proposed a mechanism based on neuroprotection that involves accumulation of cholesteryl esters esterified to PUFAs in astrocytes. Collectively, our findings suggest that lipids play a crucial role in modulation of cellular process linked to thiol metabolism and neurodegeneration


Os lipídeos abrangem uma ampla gama de moléculas hidrofóbicas presentes nas células. As características moleculares dos lipídios determinam sua localização celular e função biológica. Em geral, os lipídios são considerados componentes essenciais de membranas, reservatórios de energia e moduladores de vias de sinalização ligadas ao metabolismo celular, sobrevivência, entre outros. Em mamíferos, grande parte dos lipídios é esterificada em ácidos graxos poli-insaturados (PUFAs), especialmente os ácidos docosahexaenóico (DHA) e araquidônico (ARA), essenciais para vários processos fisiológicos, incluindo o desenvolvimento normal do cérebro. No entanto, os PUFAs são muito suscetíveis à oxidação por espécies reativas de oxigênio (ROS) geradas endogenamente. Uma vez oxidados, lipídios são capazes de modificar grupos tióis de peptídeos e proteínas, levando à modulação das vias de sinalização e alterando o balanço redox celular. No capítulo 1, foram investigados os mecanismos envolvidos na modificação de grupos tióis de peptídeos e proteínas por produtos de auto-oxidação de PUFAs. Com as análises realizadas foi possível identificar vários adutos de glutationa (GSH) covalentemente modificados por endoperóxidos cíclicos derivados de DHA e ARA. Uma análise detalhada dos espectros de MS/MS dos adutos de GSH revelou que GSH e endoperóxidos cíclicos são provavelmente ligados através de uma ligação química de enxofre-oxigênio, em uma reação que envolve um ataque nucleofílico do ânion tiolato. Além disso, sugerimos que a eficiência da modificação do tiol por endoperóxidos cíclicos também é dependente da reatividade do tiol, como demonstrado pela modificação covalente do resíduo de cisteína mais reativo (Cys111) da enzima antioxidante superóxido dismutase 1(SOD1). Modificações químicas de tióis por endoperóxidos cíclicos podem modular a agregação proteica e o status redox celular, produzindo adutos de GSH capazes de modular a inflamação, como relatado para os conjugados de GSH gerados enzimaticamente. No capítulo 2, nós investigamos o papel dos lipídios na esclerose lateral amiotrófica (ALS), uma vez que a inflamação e o estresse oxidativo nos neurônios motores contribuem para o desenvolvimento desta doença neurodegenerativa. Usando uma abordagem lipidômica não direcionada baseada em espectrometria de massa acoplada à cromatografia líquida (UHPLC-MS/MS), nós investigamos o metabolismo lipídico no córtex motor e na medula espinhal de um modelo de ratos com ALS. A análise do córtex motor mostrou que as principais alterações lipídicas foram dependentes da idade e ligadas ao metabolismo dos esfingolipídios. Em contraste, as principais alterações lipídicas na medula espinhal foram encontradas no grupo sintomático da ALS, sendo o metabolismo de ceramidas, ésteres de colesterol e cardiolipinas os mais afetados. De acordo com os resultados obtidos e dados relatados na literatura, propusemos um mecanismo baseado em neuroproteção que envolve o acúmulo de ésteres de colesterol esterificados em PUFAs em astrócitos. Coletivamente, nossos achados sugerem que os lipídios desempenham um papel crucial na modulação de processos celulares ligado à oxidação de tióis e à neurodegeneração


Subject(s)
Rats , Lipid Peroxidation , Amyotrophic Lateral Sclerosis/pathology , Lipids/analysis , Mass Spectrometry/methods , Oxidation-Reduction , Oxidative Stress , Sulfhydryl Compounds/analysis
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