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1.
Braz. j. med. biol. res ; 57: e13172, fev.2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1557326

RESUMEN

Accumulation of visceral adipose tissue is associated with metabolic syndrome (MS), insulin resistance, and dyslipidemia. Here we examined several morphometric and biochemical parameters linked to MS in a rodent litter size reduction model, and how a 30-day fish oil (FO) supplementation affected these parameters. On day 3 post-birth, pups were divided into groups of ten or three. On day 22, rats were split into control (C) and small litter (SL) until 60 days old. Then, after metabolic disturbance and obesity were confirmed, FO supplementation started for 30 days and the new groups were named control (C), FO supplemented (FO), obese (Ob), and obese FO supplemented (ObFO). Comparison was performed by Student t-test or 2-way ANOVA followed by Tukey post hoc test. At the end of the 60-day period, SL rats were hyperphagic, obese, hypoinsulinemic, normoglycemic, and had high visceral fat depot and high interleukin (IL)-6 plasma concentration. Obese rats at 90 days of age were fatter, hyperphagic, hyperglycemic, hypertriacylgliceromic, hipoinsulinemic, with low innate immune response. IL-6 production ex vivo was higher, but in plasma it was not different from the control group. FO supplementation brought all biochemical changes to normal values, normalized food intake, and reduced body weight and fat mass in obese rats. The innate immune response was improved but still not as efficient as in lean animals. Our results suggested that as soon MS appears, FO supplementation must be used to ameliorate the morpho- and biochemical effects caused by MS and improve the innate immune response.

2.
Artículo | IMSEAR | ID: sea-219671

RESUMEN

This study explored the potential of African walnut in the formulation of composite flour which can be used for bread production and in various food applications. African walnut flour was produced and used to substitute wheat flour at different levels (5 - 25%) in the production of wheat-African walnut composite flour. Functional and pasting properties of the composite flour were evaluated using standard procedures. Proximate composition, antioxidant activity, some loaf quality attributes and sensory acceptability of bread produced from the composite flour were evaluated using standard procedures. Wheat bread served as control. The composite flour showed varying functional properties which ranged from 2.43 to 3.46 (swelling capacity), 1.15 to 1.85 mL/g (water absorption capacity), 2.15 to 2.75 mL/g (oil absorption capacity), 10.80 to16.60% (foam capacity), 63.0 to 75.0% (dispersibility), 38.92 to 69.92 seconds (wetability), 0.75 to 0.79 g/mL (packed bulk density) and 0.43 to 0.47 g/mL (loose bulk density). Inclusion of African walnut reduced peak viscosity (53.92 – 148.83 RVU), trough viscosity (52.25 – 88.58 RVU), breakdown viscosity (1.67 – 60.25 RVU), final viscosity (74.08 – 191.25 RVU) and setback viscosity (21.83 – 102.67 RVU) of the composite flour. Composite bread had better protein (9.75 – 16.93%), fat (3.42 – 9.94%), ash (1.46 – 2.75%), crude fibre (0.86 – 3.64%) but reduced specific loaf volume (2.36 – 4.18 cm3/g) and loaf height (3.00 – 5.40cm) than the control, and exhibited appreciable antioxidant activity (DPPH: 31.60 – 73.09% and FRAP: 0.51 - 4.25 mg/g). In term of sensory acceptability composite bread samples produced with 5 and 10 % levels of African walnut compared favourably with bread produced from wheat flour. Thus composite flour produced from wheat and African walnut flours showed an array of physicochemical properties which could make it useful in different food applications. Acceptable bread could be produced from wheat flour substituted with African walnut flour at 10% level.

3.
Artículo | IMSEAR | ID: sea-217921

RESUMEN

Background: Post marketing surveillance of medical devices has to be done to avoid injuries and it is highly required to evaluate and ascertain the risks and benefits associated with the medical devices. Aims and Objectives: The aim of the study was to assess the knowledge and attitude about materiovigilance among doctors working in a tertiary care hospital. Materials and Methods: A cross-sectional study involving faculty and postgraduate residents of a tertiary care hospital using questionnaire which had 12 questions pertaining to attitude and knowledge of materiovigilance. Results: The survey questionnaire was sent to 300 health-care professionals among them, 259 respondents completely answered the questions. There were 96 teaching faculty, 163 were postgraduates residents. The average response rate was 86.3%. There was no statistical significant difference seen between the two groups (P = 0.85). Conclusion: More workshops and training programs need to be conducted to create awareness and reporting of adverse reactions due to medical instruments.

4.
Horiz. meÌud. (Impresa) ; 23(1)ene. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1430473

RESUMEN

Objetivo: Determinar la prevalencia y factores de riesgo asociados a la infección por virus SARS-CoV-2 en trabajadores del Instituto Nacional de Salud del Niño (INSN), en el periodo de abril 2020 a marzo 2021. Materiales y métodos: Estudio no experimental, descriptivo, transversal. La muestra corresponde a 608 trabajadores de salud que resultaron positivos a la prueba serológica rápida. Se revisaron las fichas de investigación clínica epidemiológica COVID-19 elaboradas por el Ministerio de Salud de Perú, que fueron autoadministradas por los trabajadores de salud, y el personal de Epidemiología del INSN verificó el llenado de la ficha. Los datos se introdujeron en una base de datos que sirvió para el análisis estadístico respectivo. El estudio fue aprobado por el Comité Institucional de Ética en Investigación del INSN (código de registro: PI-17/21). Resultados: La prevalencia fue de 7,24 % de COVID-19 en trabajadores del INSN entre abril del 2020 y marzo del 2021. El 71,4 % fueron mujeres, los participantes presentaron una media de edad de 44,71 años, mayoritariamente en el rango de los 30 a 59 años (83,4 %); el 65,6 % fueron asistenciales, de los cuales la mayoría fueron técnicos en enfermería. El 56,9 % de los trabajadores presentaron síntomas, principalmente fiebre/escalofríos (12,2 %), tos (8,9 %), malestar general (7,7 %), dolor de garganta (6,7 %), congestión nasal (2,5 %) y cefalea (1,3 %) . La mayoría de trabajadores residían en los distritos de Lima . Se encontró asociación significativa por sexo y grupos de edad, tipo de trabajador y perfil del trabajador. Conclusiones: La prevalencia de COVID-19 entre los trabajadores del INSN fue del 7,24 %; las características más frecuentes que mostraron diferencias significativas con el resto de los factores fueron el ser mujer, trabajador asistencial y técnica de enfermería. El 56,9 % de los trabajadores presentó síntomas, solo el 20,9 %, signos clínicos y el 10,9 % tuvo comorbilidades.


Objective: To determine the prevalence and risk factors associated with SARS-CoV-2 infection among workers of Instituto Nacional de Salud del Niño (INSN) from April 2020 to March 2021. Materials and methods: A non-experimental, descriptive, cross-sectional study. The sample consisted of 608 workers who tested positive for COVID-19 using a rapid antigen test. The COVID-19 clinical-epidemiological research sheets prepared by the Ministry of Health of Peru and self-administered by the workers were reviewed. The INSN Department of Epidemiology staff verified the completion of the sheets. The data was entered into a database, which was used for the respective statistical analysis. The study was approved by the INSN Institutional Research Ethics Committee (registration code: PI-17/21). Results: COVID-19 prevalence among INSN workers was 7.24 % from April 2020 to March 2021. Out of the workers with COVID-19, 71.4 % were women; 83.4 % were in the 30 to 59 age range with an average age of 44.71 years; 65.6 % were healthcare workers, most of whom were nursing technicians; and 56.9 % experienced symptoms, mainly fever/chills (12.2 %), cough (8.9 %), malaise (7.7 %), sore throat (6.7 %), stuffy nose (2.5 %) and headache (1.3 %). Most workers lived in Lima Centro districts (33.2 %). A significant association between sex, age groups, worker type and worker profile was found. Conclusions: COVID-19 prevalence among INSN workers was 7.24 %; the most frequent characteristics, which showed significant differences with the rest of the factors, were being a woman, healthcare worker and nursing technician. A total of 56.9 % of the workers experienced symptoms, only 20.9 % developed clinical signs and 10.9 % had comorbidities.

6.
Braz. j. med. biol. res ; 56: e12564, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1439703

RESUMEN

The need to fully exploit fishing resources due to increasing production and consequent waste generation requires research to promote the sustainability of the fishing industry. Fish waste from the industry is responsible for relevant environmental contamination. However, these raw materials contain high amounts of collagen and other biomolecules, being attractive due to their industrial and biotechnological applicability. Thus, to reduce the waste from pirarucu (Arapaima gigas) processing, this study aimed to obtain collagen from pirarucu skin tissue. The extraction process used 0.05 M sodium hydroxide, 10% butyl alcohol, and 0.5 M acetic acid, with extraction temperature of 20°C. The obtained yield was 27.8%, and through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), it was determined that the collagen obtained was type I. This study showed that collagen solubility was highest at pH 3 and the lowest solubility was at concentrations of 3% sodium chloride. The denaturation temperature of collagen was 38.1°C, and its intact molecular structure was observed using the Fourier transform infrared spectrophotometry technique with an absorption radius of 1. The results showed that it was possible to obtain collagen from pirarucu skin at 20°C, which has the typical characteristics of commercial type I collagen. In conclusion, the procedures used may be considered to be an interesting alternative for collagen extraction, a new product obtained from the processing of fish waste.

7.
Clinics ; 78: 100180, 2023. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1439917

RESUMEN

Abstract Background: Elderly patients are more susceptible to Coronavirus Disease-2019 (COVID-19) and are more likely to develop it in severe forms, (e.g., Acute Respiratory Distress Syndrome [ARDS]). Prone positioning is a treatment strategy for severe ARDS; however, its response in the elderly population remains poorly understood. The main objective was to evaluate the predictive response and mortality of elderly patients exposed to prone positioning due to ARDS-COVID-19. Methods: This retrospective multicenter cohort study involved 223 patients aged ≥ 65 years, who received prone position sessions for severe ARDS due to COVID-19, using invasive mechanical ventilation. The PaO2/FiO2 ratio was used to assess the oxygenation response. The 20-point improvement in PaO2/FiO2 after the first prone session was considered for good response. Data were collected from electronic medical records, including demographic data, laboratory/image exams, complications, comorbidities, SAPS III and SOFA scores, use of anticoagulants and vasopressors, ventilator settings, and respiratory system mechanics. Mortality was defined as deaths that occurred until hospital discharge. Results: Most patients were male, with arterial hypertension and diabetes mellitus as the most prevalent comorbidities. The non-responders group had higher SAPS III and SOFA scores, and a higher incidence of complications. There was no difference in mortality rate. A lower SAPS III score was a predictor of oxygenation response, and the male sex was a risk predictor of mortality. Conclusion: The present study suggests the oxygenation response to prone positioning in elderly patients with severe COVID-19-ARDS correlates with the SAPS III score. Furthermore, the male sex is a risk predictor of mortality.

8.
Braz. j. med. biol. res ; 56: e12326, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1420762

RESUMEN

There is a high demand for stroke rehabilitation in the Brazilian public health system, but most studies that have addressed rehabilitation for unilateral spatial neglect (USN) after stroke have been performed in high-income countries. Therefore, the aim of this study was to analyze USN patient recruitment in a multicenter noninvasive brain stimulation clinical trial performed in Brazil and to provide study design recommendations for future studies. We evaluated the reasons for exclusion of patients from a multicenter, randomized, double-blinded clinical trial of rehabilitation of USN patients after stroke. Clinical and demographic variables were compared between the included and excluded patients. A descriptive statistical analysis was performed. Only 173 of the 1953 potential neglect patients (8.8%) passed the initial screening. After screening evaluation, 87/173 patients (50.3%) were excluded for clinical reasons. Cognitive impairment led to the exclusion of 21/87 patients (24.1%). Low socioeconomic status led to the exclusion of 37/173 patients (21.4%). Difficulty obtaining transportation to access treatment was the most common reason for their exclusion (16/37 patients, 43.3%). The analyzed Brazilian institutions have potential for conducting studies of USN. The recruitment of stroke survivors with USN was restricted by the study design and limited financial support. A history of cognitive impairment, intracranial stenting or craniectomy, and lack of transportation were the most common barriers to participating in a multicenter noninvasive brain stimulation trial among patients with USN after stroke.

9.
Revue Africaine de Médecine Interne ; 10(1-2): 46-53, 2023. figures, tables
Artículo en Francés | AIM | ID: biblio-1511904

RESUMEN

Introduction : Le coma non traumatique est une urgence médicale, relativement fréquente dont les différents aspects restent encore obscurs dans les services de réanimation en Afrique. Objectif : Cette étude avait pour but de décrire les aspects épidémiologiques, étiologiques et pronostiques des comas non traumatiques (CNT). Méthodes : Il s'était agi d'une étude rétrospective descriptive menée au Centre Hospitalier Universitaire Sylvanus Olympio à l'Unité des Soins Intensifs (USI) de janvier 2018 à décembre 2019. Résultats : L'étude avait concerné 484 patients hospitalisés pour comas non traumatiques sur un total de 1835 patients. Les comas non traumatiques de l'adulte représentaient 26,4% des admissions à l'USI. L'âge moyen des patients était de 52,8 ans (extrêmes de 18 et 92 ans) avec une sex-ratio (H/F) de 0,94. Plus de la moitié des patients avait été référée de structures sanitaires périphériques (55,4%). L'hypertension artérielle (HTA) était l'antécédent le plus retrouvé dans 36,4% ; suivi du diabète et de l'infection au virus de l'immunodéficience acquise (VIH) dans 14,9% chacun. Le coma était de survenue brutale dans 77,7% des cas. Les étiologies des comas étaient dominées par les causes vasculaires dans 32,2% des cas, puis les causes infectieuses dans 27,3% des cas et les comas urémiques dans 14,1% des cas. Le pronostic était défavorable avec une mortalité de 68,6%. La première étiologie de décès concernait les causes vasculaires. Conclusion : L'amélioration du pronostic des comas non traumatiques passe nécessairement par une amélioration du plateau technique pour une meilleure prise en charge des patients


Introduction: The non-traumatic coma is a medical emergency relatively frequent which different aspects remain obscure in intensive care units in Africa. Goals: The aim of this study was therefore to describe the epidemiological, etiological and prognostic aspects of non-traumatic comas. Methodology: This was a retrospective descriptive study carried out at the Sylvanus Olympio Teaching Hospital in the Intensive Care Unit (USI) from January 2018 to December 2019. Results: The study involved 484 patients hospitalized for non-traumatic comas out of 1835 patients. Non-traumatic comas in adults were 26.4% of admissions in the Intensive Care Unit. The mean age of patients was 52.8 years of a sex ratio (M / F) of 0.94. More than half of patients (55.4%) were referred from peripheral care centers. Arterial hypertension was the most common antecedent found in 36.4%, followed by diabetes and the infection of human immunodeficiency virus (HIV) at 14.9% each. The coma was sudden aspect in 77.7% of the cases. Aetiologies of the comas were dominated by vascular causes in 32.2% of causes, then infectious in 27.3% of cases and uremic comas in 14.1% of cases. The prognosis was unfavorable with 68.6% mortality. The first etiology of death was related to vascular cases. Conclusion: The Improving of the prognosis of non-traumatic comas needs an improvement of modern medical technology for a better patient care.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Coma Postraumatismo Craneoencefálico
10.
Occup. health South. Afr. (Online) ; 29(2): :65-74, 2023. figures, tables
Artículo en Inglés | AIM | ID: biblio-1527014

RESUMEN

Background: The South African occupational health and safety regulations, prescribing risk assessments be conducted by employers, are non-prescriptive with regard to the tools and techniques to be used. Consequently, companies freely adopt the numerous available tools and techniques from which risk management decisions are derived. Thus, risk management, ensuing from the results derived from these tools and techniques, is likely to vary from company to company. Objective: The objective of the study was to evaluate risk assessment processes and methodologies that are used and recorded in noise risk assessment reports, in four manufacturing companies. Methods: This was a case study, whereby risk assessment records were obtained from four South African companies with different operational units, from the manufacturing and utilities sectors. Results: There were inter- and intra-company variations in the processes related to the legal context in which the risk assessments were conducted, the risk assessment tools and techniques used, the risk criteria definitions, the statements about the effectiveness of controls in use, and the risk evaluation outcomes. Inter- and intra-company variations in risk rankings and risk prioritisation outcomes were also observed ­ a consequence of the risk perceptions of the assessors assigning a risk level to the noise hazard. In some instances, the adopted risk assessment tools and techniques categorised the risk from noise that was at or above regulated health and safety standards as 'insignificant', which those companies used as justification for taking no further measures to eliminate or reduce the risk. Conclusion: The use of different risk assessment processes, tools and techniques resulted in some facilities categorising noise as an insignificant hazard, which may contribute to high noise emissions and uncontrolled exposures.


Asunto(s)
Medición de Riesgo
11.
Afr. J. Clin. Exp. Microbiol ; 24(2): 158-167, 2023. tables
Artículo en Inglés | AIM | ID: biblio-1427613

RESUMEN

Background: The epidemiology of human papillomavirus (HPV) infection and the pattern of HPV genotype distribution are parameters needed to assess the risk of cervical cancer. Oncogenic HPV types are well-known pathogen for lower genital tract neoplasias, representing the primary cause of cancer death in Africa and the second in Cameroon. This study was conducted to identify the various genotypes particularly the high-risk HPV types in normal and abnormal cervical cytology from women in Yaoundé, Cameroon. Methodology: This was a hospital-based, analytical cross-sectional study carried out on 226 symptomatic women wherein cervico-vaginal samples were obtained during gynaecological examination for Pap smears, HPV-DNA and genotype detection with linear array HPV strip, conducted from November 2019 to January 2021. Results: From the 226 women whose cervical samples were collected for Pap smears, 71 (31.4%) had abnormal cytology results while 155 (68.6%) had normal results. The overall HPV prevalence in the study population was 34.1% (77/226). The HPV prevalence in women with abnormal Pap smears was 100% (71/71) and are distributed in following descending order; LSIL (21.1%, 15/71), HSIL (21.1%, 15/71), ASC-US (19.7%, 14/71), ICC (19.7%, 14/71) and others (18.4%, 13/71). HPV-DNA was positive in 6 (3.9%) of the 155 women with normal cytology results, 4 (2.6%) of whom were high-risk HPV. There is statistically significant difference in the HPV prevalence between women with abnormal and normal Pap smear results (OR=3289, 95% CI=182.62-59235, p<0.0001). The frequently identified oncogenic HPV types were type 16 (31.2%, 24/77), type 45 (14.3%, 11/77) and type 18 (10.4%, 8/77). Conclusion: It is evident from our study that symptomatic women with normal Pap smear can have HR-HPV infection and should therefore be screened for HPV and followed up with periodic Pap smears to detect any abnormal change in cervical cytology results, to prevent cervical cancer development. Women should be encouraged to take up cervical screening, through Pap smears, because it is a non-invasive and cost-effective method for early detection of preinvasive lesions


Asunto(s)
Humanos , Infecciones por Papillomavirus , Vulnerabilidad Social , Terapéutica , Neoplasias del Cuello Uterino , Riesgo , Genotipo , Atención de Bajo Valor
12.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469126

RESUMEN

Abstract Dipteryx alata Vogel is a tree species widely found in Cerrado, settling preferentially in well drained soils. Studies related to ecophysiology of D. alata may contribute to the decision making about using seedlings of this species in projects aimed at the recovery of degraded areas where seasonal flooding happens. This study aimed to assess the effects of flooding on photosynthetic and antioxidant metabolism and quality of D. alata seedlings cultivated or not under flooding during four assessment periods (0, 20, 40, and 60 days), followed by 100 days after the end of each assessment period (0+100, 20+100, 40+100, and 60+100 days), allowing verifying the potential for post-flooding recovery. Flooded plants showed lower photosynthetic efficiency than non-flooded plants, regardless of the periods of exposure. However, this efficiency was recovered in the post-flooding, with values similar to that of the non-flooded seedlings. Moreover, the damage to FV/FM was evidenced by an increase in the period of exposure to flooding, but recovery was also observed at this stage of the photosynthetic metabolism. Seedling quality decreased under flooding, not varying between periods of exposure, but remained lower although the increase observed in the post-flooding period, with no recovery after flooding. The occurrence of hypertrophied lenticels associated with physiological changes and an efficient antioxidant enzyme system might have contributed to the survival and recovery of these seedlings. Thus, this species is sensitive to flooding stress but capable of adjusting and recovering metabolic characteristics at 100 days after the suspension of the water stress, but with no recovery in seedling quality. Thus, we suggested plasticity under the cultivation condition and determined that the time of 100 days is not enough for the complete resumption of growth.


Resumo Dipteryx alata Vogel é uma arbórea de ampla ocorrência no Cerrado, se estabelecendo preferencialmente em solos bem drenados. Estudos referentes à ecofisiologia de D. alata em podem contribuir para a tomada de decisão sobre o uso de mudas dessa espécie em programas de recuperação de áreas degradadas sujeitas a alagamento temporário. Objetivamos com essa pesquisa avaliar os efeitos do alagamento no metabolismo fotossintético e antioxidante, além da qualidade de mudas dessa espécie, cultivadas ou não sob alagamento durante quatro períodos de avaliação (0, 20, 40 e 60 dias) seguidos de 100 dias após o término de cada período (0+100, 20+100, 40+100, 60+100 dias), possibilitando verificar o potencial de recuperação pós-alagamento. Observamos que as plantas alagadas apresentaram menor eficiência fotossintética e danos em FV/FM entretanto houve recuperação dessas características no pós alagamento. A qualidade das mudas reduziu sob alagamento não variando entre os períodos de exposição e embora tenha aumentado no pós-alagamento manteve-se menor não se recuperando. A ocorrência de lenticelas hipertrofiadas associadas a alterações fisiológicas e um eficiente sistema enzimático antioxidante devem ter contribuído para a sobrevivência e recuperação metabólica dessas mudas. Diante disso, sugerimos que a espécie é sensível ao estresse por alagamento, mas capaz de se ajustar e recuperar as características metabólicas 100 dias após a suspensão deste estresse hídrico, no entanto a qualidade da mudas não apresentou recuperação, assim, sugerimos plasticidade diante da condição de cultivo e ressaltamos que o tempo de 100 dias não é suficiente para a completa retomada do crescimento.

14.
Braz. j. biol ; 83: e243910, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278525

RESUMEN

Abstract Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.


Resumo O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T.cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.


Asunto(s)
Humanos , Animales , Trypanosoma cruzi/genética , Xerodermia Pigmentosa , Daño del ADN/genética , Biología Computacional , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Reparación del ADN/genética
15.
Braz. j. biol ; 83: e244718, 2023. graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278533

RESUMEN

Abstract The objective of this study was to evaluate the activity of antioxidant enzymes, the functioning of the photosystem II and quality of C. xanthocarpa seedlings cultivated under intermittent water deficit and shading levels and the influence of shading on recovery potential after suspension of the stress conditions. The seedlings were subjected to three levels of shading (0, 30, and 70%), six periods of evaluation (start: 0 days; 1st and 2nd photosynthesis zero: 1st and 2nd P0; 1st and 2nd recovery: 1stand 2nd REC; and END), and two forms of irrigation (control: periodically irrigated to maintain 70% substrate water retention capacity, and intermittent irrigation: suspension of irrigation). The plants subjected to intermittent irrigation conditions at 0% shading showed a reduction in water potential (Ψw) and potential quantum efficiency of photosystem II (Fv/Fm) and maximum efficiency of the photochemical process (Fv/F0) and an increase in basal quantum production of the non-photochemical processes (F0/Fm). Superoxide dismutase (SOD) activity was higher in the leaves than in the roots. The C. xanthocarpa is a species sensitive to water deficit but presents strategies to adapt to an environment under temporary water restriction, which are more temporary are most efficient under shading. The seedlings with water deficit at all levels of shading exhibited higher protective antioxidant activity and lower quality at 0% shading. The shading minimizes prevents permanent damage to the photosystem II and after the re-irrigation, the evaluated characteristics showed recovery with respect to the control group, except POD and SOD activities in the leaves.


Resumo O objetivo deste estudo foi avaliar a atividade de enzimas antioxidantes, o funcionamento do fotossistema II e a qualidade de mudas de C. xanthocarpa cultivadas sob déficit hídrico intermitente e níveis de sombreamento e a influência do sombreamento sobre o potencial de recuperação após suspensão das condições de estresse. As mudas foram submetidas a três níveis de sombreamento (0, 30 e 70%), seis períodos de avaliação (início: 0 dias; 1ª e 2ª fotossíntese zero: 1ª e 2ª P0; 1ª e 2ª recuperação: 1ª e 2ª REC; e final), e duas formas de irrigação (controle: periodicamente irrigado para manter 70% da capacidade de retenção de água do substrato, e irrigação intermitente: suspensão da irrigação). As plantas submetidas às condições de irrigação intermitente a 0% de sombreamento apresentaram redução do potencial hídrico (Ψw) e eficiência quântica potencial do fotossistema II (Fv/Fm) e máxima eficiência do processo fotoquímico (Fv/F0) e aumento da produção quantica basal dos processos não fotoquímicos (F0/Fm). A atividade da superóxido dismutase (SOD) foi maior nas folhas do que nas raízes. C. xanthocarpa é uma espécie sensível ao déficit hídrico, mas apresenta estratégias para se adaptar a um ambiente com restrição hídrica temporária, sendo mais eficientes sob sombreamento. As mudas com déficit hídrico em todos os níveis de sombreamento exibiram maior atividade antioxidante protetora e menor qualidade no sombreamento 0%. O sombreamento minimiza danos permanentes ao fotossistema II e após a re-irrigação, as características avaliadas apresentaram recuperação em relação ao grupo controle, exceto atividades de POD e SOD nas folhas.


Asunto(s)
Agua , Plantones , Fotosíntesis , Hojas de la Planta , Antioxidantes
16.
Braz. j. biol ; 83: e248083, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278546

RESUMEN

Abstract Species of the genus Cordia have shown biological activities, such as anti-inflammatory, analgesic, antioxidant, antiviral, and antifungal activities. The species Cordia glabrata (MART) A.DC. Has no information concerning its phytochemical profile and possible biological activities. Thus, this study aimed to evaluate this profile in ethanolic extracts of young, adult and senescent leaves, as well as their antioxidant, photoprotective, antimicrobial, and virucidal potentials. Phytochemical analysis was performed by TLC (thin-layer chromatography) and showed the presence of flavonoids, tannins, and terpenes. The evaluation by UPLC-MS/MS (Ultra performance liquid chromatography - tandem mass spectrometer) evidenced the presence of caffeic (3.89 mgL-1), p-cumaric (6.13 mgL-1), and ferulic (0.58 mgL-1) acids, whilst, in GC/MS (Gas chromatography-mass spectrometry) analysis there was a greater amount of palmitic (51.17%), stearic (20.34%), linoleic (9.62%), and miristic (8.16%) fatty acids. The DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS+ (2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radicals were used to verify the potential antioxidant activity, observing a better activity for the leaf extract in the adult phenological stage: 54.63 ± 1.06 µgmL-1 (DPPH) and 44.21 ± 1.69 mM (ABTS). The potential photoprotective activity of the extracts was determined by spectrophotometry and the in vitro values of SPF (Sun Protection Factor) in young and adult leaves (5.47 and 5.41, respectively) showed values close to the minimum SPF of 6.0 required by ANVISA (Brazilian Health Regulatory Agency). It was not observed an antimicrobial activity for Staphylococcus aureus with a minimum inhibitory concentration of 2000 μgmL-1, however the anti-herpetic assay against the Herpes simplex virus type 2 (HSV-2) showed a potent virucidal activity at the tested concentrations with CV50 value <0.195 μgmL-1 and a Selectivity Index (SI = CC50 / CV50) greater than 448. The results obtained in this study suggest that extracts of leaves of C. glabrata in their adult phenological stage have potential antioxidant, photoprotective and virucidal activity, considering in vitro test results.


Resumo Espécies do gênero Cordia apresentam atividades biológicas, como anti-inflamatória, analgésica, antioxidante, antiviral e antifúngica. Para a espécie Cordia glabrata (MART) A.DC., ainda não existem informações sobre seu perfil fitoquímico e possíveis atividades biológicas, deste modo, o presente estudo teve como objetivo avaliar este perfil em extratos etanólicos de folhas jovens, adultas e senescentes, bem como o potencial antioxidante, fotoprotetor, antimicrobiano e virucida. A análise fitoquímica foi realizada por CCD (Cromatografia em Camada Delgada), mostrando a presença de flavonóides, taninos e terpenos. Na avaliação por CLAE EM/EM (Cromatografia Líquida de Ultra Eficiência acoplada a Espectrometria de Massas) foi evidenciado a presença dos ácidos caféico (3,89 mgL-1), p-cumárico (6,13 mgL-1) e ferúlico (0,58 mgL-1), paralelamente, na CG/EM (Cromatografia Gasosa acoplada a Espectrometria de Massas) verificou-se maior quantidade dos ácidos graxos palmítico (51,17%), esteárico (20,34%), linoléico (9,62%) e mirístico (8,16%). Os radicais DPPH (2,2-Difenil-1-picrilhidrazil) e ABTS+ (2′-Azino-bis (ácido 3-etilbenzotiazolina-6-sulfônico)) foram utilizados para verificar o potencial antioxidante, observando-se uma atividade superior para o extrato da folha em sua fase fenológica adulta: 54,63 ± 1,06 µgmL-1 (DPPH) e 44,21 ± 1,69 mM (ABTS+). A potencial atividade fotoprotetora dos extratos foi determinada espectrofotometricamente e os valores in vitro de FPS (Fator de Proteção Solar) em folhas jovens e adultas (5,47 e 5,41 respectivamente) apresentaram valores próximos ao FPS mínimo de 6,0 exigido pela ANVISA (Agência Nacional de Vigilância Sanitária). Não foi observada atividade antimicrobiana para Staphylococcus aureus sendo a concentração inibitória mínima de 2000 μgmL-1, no entanto o ensaio anti-herpético contra o vírus Herpes simplex tipo 2 (HSV-2) mostrou uma potente atividade virucida nas concentrações testadas com um valor de CV50 <0,195 μgmL-1 e um Índice de Seletividade (IS = CC50 / CV50) maior que 448. Os resultados obtidos neste estudo sugerem que extratos de folhas de C. glabrata em seu estágio fenológico adulto apresentam potencial antioxidante, fotoprotetora e virucida, considerando os resultados de testes in vitro.


Asunto(s)
Cordia , Antiinfecciosos , Antivirales/farmacología , Brasil , Extractos Vegetales/farmacología , Cromatografía Liquida , Hojas de la Planta , Espectrometría de Masas en Tándem , Antioxidantes/farmacología
18.
Braz. j. biol ; 83: e246451, 2023. graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1339402

RESUMEN

Abstract Dipteryx alata Vogel is a tree species widely found in Cerrado, settling preferentially in well drained soils. Studies related to ecophysiology of D. alata may contribute to the decision making about using seedlings of this species in projects aimed at the recovery of degraded areas where seasonal flooding happens. This study aimed to assess the effects of flooding on photosynthetic and antioxidant metabolism and quality of D. alata seedlings cultivated or not under flooding during four assessment periods (0, 20, 40, and 60 days), followed by 100 days after the end of each assessment period (0+100, 20+100, 40+100, and 60+100 days), allowing verifying the potential for post-flooding recovery. Flooded plants showed lower photosynthetic efficiency than non-flooded plants, regardless of the periods of exposure. However, this efficiency was recovered in the post-flooding, with values similar to that of the non-flooded seedlings. Moreover, the damage to FV/FM was evidenced by an increase in the period of exposure to flooding, but recovery was also observed at this stage of the photosynthetic metabolism. Seedling quality decreased under flooding, not varying between periods of exposure, but remained lower although the increase observed in the post-flooding period, with no recovery after flooding. The occurrence of hypertrophied lenticels associated with physiological changes and an efficient antioxidant enzyme system might have contributed to the survival and recovery of these seedlings. Thus, this species is sensitive to flooding stress but capable of adjusting and recovering metabolic characteristics at 100 days after the suspension of the water stress, but with no recovery in seedling quality. Thus, we suggested plasticity under the cultivation condition and determined that the time of 100 days is not enough for the complete resumption of growth.


Resumo Dipteryx alata Vogel é uma arbórea de ampla ocorrência no Cerrado, se estabelecendo preferencialmente em solos bem drenados. Estudos referentes à ecofisiologia de D. alata em podem contribuir para a tomada de decisão sobre o uso de mudas dessa espécie em programas de recuperação de áreas degradadas sujeitas a alagamento temporário. Objetivamos com essa pesquisa avaliar os efeitos do alagamento no metabolismo fotossintético e antioxidante, além da qualidade de mudas dessa espécie, cultivadas ou não sob alagamento durante quatro períodos de avaliação (0, 20, 40 e 60 dias) seguidos de 100 dias após o término de cada período (0+100, 20+100, 40+100, 60+100 dias), possibilitando verificar o potencial de recuperação pós-alagamento. Observamos que as plantas alagadas apresentaram menor eficiência fotossintética e danos em FV/FM entretanto houve recuperação dessas características no pós alagamento. A qualidade das mudas reduziu sob alagamento não variando entre os períodos de exposição e embora tenha aumentado no pós-alagamento manteve-se menor não se recuperando. A ocorrência de lenticelas hipertrofiadas associadas a alterações fisiológicas e um eficiente sistema enzimático antioxidante devem ter contribuído para a sobrevivência e recuperação metabólica dessas mudas. Diante disso, sugerimos que a espécie é sensível ao estresse por alagamento, mas capaz de se ajustar e recuperar as características metabólicas 100 dias após a suspensão deste estresse hídrico, no entanto a qualidade da mudas não apresentou recuperação, assim, sugerimos plasticidade diante da condição de cultivo e ressaltamos que o tempo de 100 dias não é suficiente para a completa retomada do crescimento.


Asunto(s)
Plantones , Dipteryx , Fotosíntesis , Inundaciones , Antioxidantes
19.
Braz. j. biol ; 83: 1-10, 2023. graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468814

RESUMEN

The objective of this study was to evaluate the activity of antioxidant enzymes, the functioning of the photosystem II and quality of C. xanthocarpa seedlings cultivated under intermittent water deficit and shading levels and the influence of shading on recovery potential after suspension of the stress conditions. The seedlings were subjected to three levels of shading (0, 30, and 70%), six periods of evaluation (start: 0 days; 1st and 2nd photosynthesis zero: 1st and 2nd P0; 1st and 2nd recovery: 1stand 2nd REC; and END), and two forms of irrigation (control: periodically irrigated to maintain 70% substrate water retention capacity, and intermittent irrigation: suspension of irrigation). The plants subjected to intermittent irrigation conditions at 0% shading showed a reduction in water potential (Ψw) and potential quantum efficiency of photosystem II (Fv/Fm) and maximum efficiency of the photochemical process (Fv/F0) and an increase in basal quantum production of the non-photochemical processes (F0/Fm). Superoxide dismutase (SOD) activity was higher in the leaves than in the roots. The C. xanthocarpa is a species sensitive to water deficit but presents strategies to adapt to an environment under temporary water restriction, which are more temporary are most efficient under shading. The seedlings with water deficit at all levels of shading exhibited higher protective antioxidant activity and lower quality at 0% shading. The shading minimizes prevents permanent damage to the photosystem II and after the re-irrigation, the evaluated characteristics showed recovery with respect to the control group, except POD and SOD activities in the leaves.


O objetivo deste estudo foi avaliar a atividade de enzimas antioxidantes, o funcionamento do fotossistema II e a qualidade de mudas de C. xanthocarpa cultivadas sob déficit hídrico intermitente e níveis de sombreamento e a influência do sombreamento sobre o potencial de recuperação após suspensão das condições de estresse. As mudas foram submetidas a três níveis de sombreamento (0, 30 e 70%), seis períodos de avaliação (início: 0 dias; 1ª e 2ª fotossíntese zero: 1ª e 2ª P0; 1ª e 2ª recuperação: 1ª e 2ª REC; e final), e duas formas de irrigação (controle: periodicamente irrigado para manter 70% da capacidade de retenção de água do substrato, e irrigação intermitente: suspensão da irrigação). As plantas submetidas às condições de irrigação intermitente a 0% de sombreamento apresentaram redução do potencial hídrico (Ψw) e eficiência quântica potencial do fotossistema II (Fv/Fm) e máxima eficiência do processo fotoquímico (Fv/F0) e aumento da produção quantica basal dos processos não fotoquímicos (F0/Fm). A atividade da superóxido dismutase (SOD) foi maior nas folhas do que nas raízes. C. xanthocarpa é uma espécie sensível ao déficit hídrico, mas apresenta estratégias para se adaptar a um ambiente com restrição hídrica temporária, sendo mais eficientes sob sombreamento. As mudas com déficit hídrico em todos os níveis de sombreamento exibiram maior atividade antioxidante protetora e menor qualidade no sombreamento 0%. O sombreamento minimiza danos permanentes ao fotossistema II e após a re-irrigação, as características avaliadas apresentaram recuperação em relação ao grupo controle, exceto atividades de POD e SOD nas folhas.


Asunto(s)
Enzimas/biosíntesis , Estrés Fisiológico , Fotosíntesis , Myrtaceae/crecimiento & desarrollo , Myrtaceae/metabolismo
20.
Braz. j. biol ; 83: 1-15, 2023. tab, ilus, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468821

RESUMEN

Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T. cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.


O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T. cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.


Asunto(s)
Animales , Cruzamientos Genéticos , Daño del ADN , Expresión Génica , Trypanosoma cruzi/genética
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