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1.
J Prosthet Dent ; 2022 Aug 24.
Article in English | MEDLINE | ID: mdl-36028339

ABSTRACT

This article describes a digital workflow for ceramic veneer preparation using computer-aided design and computer-aided manufacturing technology. A digital waxing was planned on the exocad software program to reestablish esthetic and functional parameters. Then, the digital guides for veneer preparation were designed by using the Meshmixer design software program to control the tooth structure removed during preparation to the minimal thickness necessary for the definitive restorations. The digital guides were printed in an additively manufactured clear resin and used in the preparation appointment, allowing a more conservative and controlled preparation.

2.
Fisioter. Pesqui. (Online) ; 29(2): 216-222, maio-ago. 2022. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1394359

ABSTRACT

RESUMO A infecção por SARS-CoV-2 pode ocasionar a síndrome respiratória aguda grave (SRAG), levando a hipoxemia. A avaliação da capacidade física pode ser realizada anteriormente à alta hospitalar, através de testes de exercícios submáximos. O objetivo deste estudo foi avaliar a capacidade física e a tolerância ao exercício físico por meio do teste de degrau de seis minutos (TD6) em pacientes hospitalizados com diagnóstico de COVID-19 que fizeram uso de suporte de oxigênio (O2) durante a internação. Trata-se de um estudo prospectivo e intervencionista, incluindo pacientes com idade entre 18 e 90 anos, que necessitaram de oxigenoterapia durante a hospitalização. Foi realizada avaliação através do Perme escore, seguida do TD6, com análise da saturação periférica de oxigênio (SpO2), frequência cardíaca (FC), pressão arterial (PA) e percepção subjetiva do esforço através da escala de Borg, antes e imediatamente após o TD6. Foram avaliados 31 pacientes, com idade média de 51,9 anos. O dispositivo de O2 mais utilizado foi o cateter nasal (CN), em 64,5% dos pacientes. Em relação à FC, PA e escala de Borg, pudemos observar um aumento no valor médio dessas variáveis após o TD6. A SpO2 teve uma média menor quando comparada à avaliação inicial do TD6. O teste foi finalizado por 86,9% dos pacientes, sendo que, destes, 48,3% finalizaram com interrupções; 12,9% dos participantes suspenderam o teste. O TD6 foi capaz de avaliar a capacidade física e a tolerância ao exercício, tornando-se uma ferramenta eficaz para avaliação do paciente com COVID-19.


RESUMEN La infección por SARS-CoV-2 puede provocar el síndrome respiratorio agudo severo (SRAS), resultando en hipoxemia. La evaluación de la capacidad física se puede realizar antes del alta hospitalaria mediante pruebas de ejercicio submáximas. El objetivo de este estudio fue evaluar la capacidad física y la tolerancia al ejercicio a través del test de escalón de seis minutos (TE6) en pacientes hospitalizados por Covid-19 que utilizaron soporte de oxígeno (O2) durante la hospitalización. Se trata de un estudio prospectivo e intervencionista, en el que se incluyeron a pacientes con edades entre los 18 y los 90 años, que necesitaron la oxigenoterapia durante su hospitalización. La evaluación se realizó mediante el puntaje de Perme, seguido del TE6, con análisis de saturación de oxígeno periférico (SpO2), frecuencia cardíaca (FC), presión arterial (PA) y esfuerzo percibido mediante la escala de Borg, antes e inmediatamente después del TE6. Se evaluaron a 31 pacientes, con una edad media de 51,9 años. El dispositivo de O2 más utilizado fue el catéter nasal (CN) por el 64,5% de los pacientes. Con relación a la FC, PA y la escala de Borg, se observa un aumento en el valor medio de estas variables después del TE6. La SpO2 tuvo una media más baja en comparación con la evaluación inicial del TE6. El 86,9% de los pacientes completaron el test, de los cuales el 48,3% terminó con interrupciones; y el 12,9% lo suspendió. El TE6 pudo evaluar la capacidad física y la tolerancia al ejercicio, lo que resulta ser una herramienta eficaz para evaluar a los pacientes con Covid-19.


ABSTRACT SARS-CoV-2 infection can cause severe acute respiratory syndrome (SARS), leading to hypoxemia. Physical capacity assessment can be performed before hospital discharge using submaximal exercise testing. This study sought to assess physical capacity and exercise tolerance with the six-minute step test (6MST) in hospitalized COVID-19 patients who required oxygen (O2) support during hospitalization. A prospective, interventional study was conducted with patients aged from 18 to 90 years who required oxygen therapy during hospitalization. Assessment was performed using Perme Score, followed by the 6MST tests, assessing the peripheral oxygen saturation (SpO2), heart rate (HR), blood pressure (BP), and subjective exertion perception by Borg Scale, before and immediately after the 6MST. A total of 31 patients, with a mean age of 51.9 years, were evaluated. Nasal cannula (NC) was the most used device (64.5% of patients). Regarding HR, BP, and Borg Scale, their mean value increased after 6MST. SpO2 showed a lower mean value after 6MST. Out of the 86.9% of patients who completed the test, 48.3% completed it with interruptions, and 12.9% had to suspend it. The 6MST was able to assess physical capacity and exercise tolerance, proving to be an effective tool for evaluating COVID-19 patients.

3.
Article in English | MEDLINE | ID: mdl-33498902

ABSTRACT

INTRODUCTION: Digital impressions in implant dentistry rely on many variables, and their accuracy, particularly in complete edentulous patients, is not well understood. Aim. The purpose of this literature review was to determine which factors may influence the accuracy of digital impressions in implant dentistry. Emphasized attention was given to the design of the intra-oral scan body (ISB) and scanning techniques. MATERIALS AND METHODS: A Medline, PubMed and EBSCO Host databases search, complemented by a hand search, was performed in order to select relevant reports regarding the appliance of digital impressions in implant dentistry. The search subject included but was not limited to accuracy of digital impressions in implant dentistry, digital scanning techniques, the design and material of the ISBs, and the depth and angulation of the implant. The related titles and abstracts were screened, and the remaining articles that fulfilled the inclusion criteria were selected for full-text readings. RESULTS: The literature search conducted for this review initially resulted in 108 articles, among which only 21 articles fulfilled the criteria for inclusion. Studies were evaluated according to five subjects: accuracy of digital impressions in implant dentistry; the design and material of the intra-oral scan bodies; scanning technique; the influence of implants depth/angulations on the digital impression and accuracy of different intra-oral scanner devices. CONCLUSIONS: The accuracy of digital impressions in implant dentistry depends on several aspects. The depth/angulation of the implant, the experience of the operator, the intra-oral scanner used, and environmental conditions may influence the accuracy of digital impressions in implant dentistry. However, it seems that ISBs' design and material, as well as scanning technique, have a major impact on the trueness and precision of digital impressions in implant dentistry. Future research is suggested for the better understanding of this subject, focusing on the optimization of the ISB design and scanning protocols.


Subject(s)
Computer-Aided Design , Mouth, Edentulous , Dental Impression Technique , Dentistry , Humans , Prostheses and Implants
4.
J Manipulative Physiol Ther ; 43(3): 247-256, 2020.
Article in English | MEDLINE | ID: mdl-32703614

ABSTRACT

OBJECTIVE: To investigate the effectiveness of strengthening the hip muscles in addition to strengthening the pelvic floor muscles (PFM) in the treatment of stress urinary incontinence. METHODS: This study used a prospective, assessor-blind, randomized clinical trial with parallel groups. We randomly allocated 47 individuals with stress urinary incontinence to 2 groups: 1 performing only pelvic floor strengthening exercises (PF, n = 21) and the other performing pelvic floor strengthening exercises plus exercises for the gluteus maximus and medius and hip adductor muscles (PFH, n = 22). Four individuals did not complete the study. Frequency of urine leakage was the primary outcome (3-day voiding diary and a follow-up voiding diary). Secondary outcomes were pelvic floor muscle strength (Ortiz scale, PERFECT scheme [Oxford Scale], and perineometry) and quality of life (QoL; International Consultation on Incontinence Questionnaire-Short Form and King's Health Questionnaire), which were evaluated by a blinded assessor before and after 20 sessions over 10 weeks. RESULTS: Regarding the daily frequency of urine loss evaluated by the follow-up voiding diary, an effect of group was observed (P < .001), with the PFH group showing a significant decrease in daily loss frequency, although no significant differences were found in the comparison between groups for the 3-day voiding diary, QoL, or functional assessment of the PFM. CONCLUSION: Strengthening the PFM together with the hip synergic muscles showed better results for frequency of daily urine loss throughout the sessions, although there was no accompanying superiority in improvement of strength, perineometry, or QoL over the group that performed only PFM-strengthening exercises.


Subject(s)
Exercise Therapy/methods , Muscle Contraction/physiology , Pelvic Floor/physiology , Urinary Incontinence, Stress/therapy , Adult , Female , Humans , Middle Aged , Physical Therapy Modalities , Prospective Studies , Quality of Life/psychology , Surveys and Questionnaires , Treatment Outcome , Urinary Incontinence, Stress/physiopathology
5.
Rev. enferm. UFPE on line ; 11(supl.12): 5361-5369, dez.2017. ilus, tab, graf
Article in Portuguese | BDENF - Nursing | ID: biblio-1032366

ABSTRACT

Objetivo: investigar ações para a redução de incertezas vivenciadas por pais de recém-nascidos internadosem Unidades de Terapia Intensiva. Método: revisão integrativa, com busca de produção científica entre 2012e 2016, nas bases de dados Medline, Journal Storage e no Portal de Periódicos da Capes, com os descritorescontrolados em inglês e português. Também, foram acrescentados quatro artigos a partir da busca manual noGoogle Achademics. A análise de conteúdo foi realizada de forma categorial e temática, a partir daidentificação dos núcleos de sentido dos dez artigos selecionados. Resultados: identificaram-se trêscategorias: contribuintes da incerteza; intervenções da equipe de saúde que auxiliaram na redução daincerteza; estratégias de enfrentamento adotadas pelos pais. Conclusão: a literatura evidenciou que aincerteza é um sentimento vivenciado por todos os pais, sendo influenciada, principalmente, pela capacidadecognitiva dos pais, familiaridade com o fato, congruência dos fatos e a estrutura de apoio social. Ações queauxiliam na redução das incertezas dos pais tornam-se imprescindíveis, pois a inadaptação a essa novacondição pode agravar a saúde dos pais e, consequentemente, do infante.


Subject(s)
Male , Female , Humans , Adaptation, Psychological , Nursing, Team , Uncertainty , Parents , Infant, Newborn , Professional-Family Relations , Nursing Theory , Intensive Care Units, Neonatal , MEDLINE
6.
World J Microbiol Biotechnol ; 32(10): 168, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27565778

ABSTRACT

Shiitake mushroom consumption is increasing in Brazil. In addition to the implementation of new production methods, it is also important to increase productivity, quality and reduce production costs. In this study, six commercial Lentinula edodes strains were characterized for genetic diversity (rep-PCR analysis) and mushroom production (yield, number and weight of individual mushrooms) using different substrates and cultural conditions. All strains showed genetic differences by repetitive element palindromic based-polymerase chain reaction (rep-PCR). The richest substrate resulted in the greatest production under both environmental conditions. Strains LE4 and LE6 produced the majority of their mushrooms earlier than the other strains. The highest number of mushrooms was observed in the LE6 strain while the highest weights of individual mushrooms were observed in the LE4 strain. Controlled environmental conditions resulted in superior production for all strains, except for LE4, which had empirically greater yield in the semi-controlled environmental condition.


Subject(s)
Axenic Culture/methods , Shiitake Mushrooms/growth & development , Shiitake Mushrooms/genetics , Agriculture/methods , Brazil , DNA, Fungal/analysis , Genetic Variation , Polymerase Chain Reaction/methods , Quantitative Trait Loci , Shiitake Mushrooms/classification
7.
Rev. bras. farmacogn ; 26(4): 420-426, July-Aug. 2016. tab, graf
Article in English | LILACS | ID: lil-792709

ABSTRACT

ABSTRACT This study evaluated the effects of using passion fruit peel flour together with diet therapy and counseling in 36 patients with HIV lipodystrophy who were in an ambulatory clinic in a university hospital. The patients were divided into two groups. One received 30 g of passion fruit peel flour daily for 90 days and diet therapy counseling. The other group received only diet therapy counseling. The metabolic changes were analyzed before and after the intervention, with a significance level predetermined at p ≤ 0.05. The use of passion fruit peel flour was effective in reducing total cholesterol and triacylglycerides after 30 days. The concentrations of LDL-C decreased, while HDL-C increased in the blood of lipodystrophy patients after 90 days passion fruit peel flour treatment. No significant differences in food consumption were seen between groups. The use of 30 g of passion fruit peel flour for 90 days together with diet therapy counseling was effective in improving plasma concentrations of total cholesterol, LDL-C, HDL-C and triacylglycerides.

8.
Photochem Photobiol ; 91(4): 980-4, 2015.
Article in English | MEDLINE | ID: mdl-25880711

ABSTRACT

A firefly luciferase (LUC)-based bioluminescent assay for total free fatty acids (FFA) is presented. It is based on LUC's capability of converting FFA into fatty acyl-adenylates with consumption of adenosine 5'-triphosphate (ATP). Since ATP is a cosubstrate in LUC's bioluminescent reaction, together with firefly D-luciferin (D-LH2 ) and atmospheric oxygen (O2 ), any reduction in the assay's ATP content will lead to a decrease in the bioluminescent signal, which is proportional to the amount of FFA. Using FFA mixtures containing myristic (14:0), palmitic (16:0), stearic (18:0), oleic (18:1) and arachidonic acid (20:4) in ethanol, the assay was optimized through statistical experimental design methodology, namely fractional factorial (screening) and central composite (optimization) designs. The optimized method requires 2 µL of sample per tube in a final reaction volume of 50 µL. It is linear in the concentration range from 1 to 20 µm, with limits of detection (LOD) and quantitation (LOQ) of 1.3 and 4.5 µm, respectively. The method proved to be simple to perform, demands low reagent volumes, it is sensitive and robust and may be adapted to high-throughput screening.


Subject(s)
Coleoptera/enzymology , Fatty Acids, Nonesterified/analysis , Luciferases/metabolism , Luminescence , Animals
9.
World J Microbiol Biotechnol ; 30(9): 2419-25, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24849009

ABSTRACT

The composition and genetic diversity of fungal populations during phase II of compost production for the cultivation of Agaricus subrufescens was determined using culture-dependent and -independent methods on days 3, 6, 10, 12, and 14 of phase II composting. The isolates were morphologically characterized and subsequently analyzed using repetitive extragenic palindromic sequences (rep-PCR), and the intergenic region was sequenced to genetically identify the isolates. Changes on in the filamentous fungi population were analyzed using denaturing gradient gel electrophoresis (DGGE), and the resulting bands were sequenced. The population did not significantly change from day 3 to 10 (2.55 x 10(5) -6 x 10(5) CFU g(-1)), and maximum counts on day 14 of phase II composting (6.92 log CFU g(-1)). In the morphological characterization, Scytalidium thermophilum, Thermomyces lanuginosus, and Thermomyces ibadanensis were the most abundant identified species. The 26 most abundant isolates identified by morphological analysis were characterized using rep-PCR. A significant amount of genetic diversity was detected among the isolates of all three studied species. Based on the DGGE analysis, the diversity of the fungi was reduced during phase II composting, and S. thermophilum was the predominant species identified throughout the entire process. Thus, this study presents the first report of the involvement of T. ibadanensis in the production of compost for Agaricus mushroom cultivation.


Subject(s)
Agaricus/growth & development , Biota , Fungi/classification , Fungi/radiation effects , Soil Microbiology , Soil , Cluster Analysis , Colony Count, Microbial , Denaturing Gradient Gel Electrophoresis , Fungi/cytology , Fungi/genetics , Genotype , Genotyping Techniques , Mycological Typing Techniques , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Temperature
10.
Rev. Inst. Adolfo Lutz ; 71(4): 670-676, out.-dez. 2012. tab, graf
Article in Portuguese | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: lil-706161

ABSTRACT

Bactérias psicrotróficas isoladas da parede, do fundo e da pá de homogeneização de tanques coletivos de resfriamento de leite, após o processo de higienização, foram identificadas e caracterizadas quanto à capacidade de produzir lipase, lecitinas e e protease, bem como determinada a sensibilidade dos isolados a antibióticos. Foram coletadas amostras de 32 tanques coletivos, localizados em diferentes cidades no sul do estado de Minas Gerais, por meio de swab de amostra da superfície, e analisadas pelas técnicas de diluições seriadas com plaqueamento em ágar triptona de soja e incubação das placas a 7 ºC por10 dias. As bactérias isoladas foram identificadas bioquimicamente pelos kits API 20NE (Biomérieux-Brasil) e Bactray I e II (Laborclin-Brasil). Foram identificados 197 isolados, os quais foram caracterizados quanto à produção de lipase, lecitinas e e protease. Para efetuar o teste de resistência a antibióticos, 21 isolados foram selecionados. Contagens entre < 1 e 108 UFC/cm2 foram observadas, com prevalência de Serratia sp., Klebsiela sp. e espécies do gênero Pseudomonas sp. Os isolados identificados apresentaram elevada atividade proteolítica e lipolítica, e a atividade de lecitinas e foi menos pronunciada. A multidroga resistência foi detectada em 54 por cento dos isolados analisados.


Subject(s)
Anti-Bacterial Agents , Bacteria/isolation & purification , Milk , Lipase , Drug Resistance, Microbial
11.
J Photochem Photobiol B ; 102(3): 218-23, 2011 Mar 02.
Article in English | MEDLINE | ID: mdl-21216615

ABSTRACT

This paper presents the main results of RP-HPLC-MS and microscale NMR analysis performed on Accompanying similar to Luciferin (AsLn(x)), compounds present in extracts of the bioluminescent earthworm Fridericia heliota that display similarities with Fridericia's luciferin, the substrate of the bioluminescent reaction. Three isomers of AsLn were discovered, AsLn(1), AsLn(2) and AsLn(3), all of which present a molecular weight of 529 Da. Their UV-Vis absorption spectra show maxima at 235 nm for AsLn(1), 238 and 295 nm for AsLn(2) and 241 and 295nm for AsLn(3). MS(n) fragmentation patterns suggest the existence of carboxylic acid and hydroxyl moieties, and possibly chemical groups found in other luciferins like pterin or benzothiazole. The major isomer, AsLn(2), presents an aromatic ring and alkene and alkyl moieties. These luciferin-like compounds can be used as models that could give further insights into the structure of this newly discovered luciferin.


Subject(s)
Chromatography, High Pressure Liquid/methods , Firefly Luciferin/chemistry , Luminescent Agents/chemistry , Magnetic Resonance Spectroscopy/methods , Mass Spectrometry , Oligochaeta/chemistry , Animals , Chromatography, Reverse-Phase , Luminescent Agents/isolation & purification
12.
Neotrop. ichthyol ; 9(3): 547-558, 2011. ilus, graf, tab
Article in English | LILACS | ID: lil-600882

ABSTRACT

There is little knowledge on the reproduction of the genus Alphestes. The reproduction of the Mutton hamlet, Alphestes afer, sampled in Pernambuco reefs (Brazil) was studied based on macroscopic analysis during reproductive period and histological analysis of gonad material from March 2008 to October 2009. This study showed that A. afer is a diandric, protogynous hermaphrodite. Sex change followed protogynous mode in two pathways: primary males formed from immature female individuals or secondary males formed from resting, ripe or spent female individuals. The numerical distribution of gonad classes by size indicated that females from 11-18 cm L T were immature while females from 16-25 cm L T and males from 12-22 cm L T were in various stages of gonadal development. Individuals identified as immature bisexual and transitional (presenting both ovarian and sperm tissue) were sized from 16-24 cm L T. Size of first reproduction for females was 18 cm L T and for males was 12 cm L T. Alphestes afer showed multiple spawning, with spawning season period from August to December 2008 and from August to October 2009. The sex-ratio (females: males) in 2008 and 2009 was 0.94:1 during the months of spawning season. Males were smaller than females, reaching maximum size of 22 cm compared to 25 cm observed for females. Males showed a high sperm competition rank (3.8), suggesting intense sperm competition. This latter is a possible indication of a shift in the mating group structure from paired to group spawning. The presence of small males added to high sperm competition index, suggest that this species, while retaining the protogynous pattern, has a reproductive strategy similar to gonochorist epinephelids.


Há pouco conhecimento sobre a reprodução do gênero Alphestes. A reprodução do sapé Alphestes afer coletado nos recifes de Pernambuco (Brasil) foi estudada baseada em análises macroscópicas durante o período reprodutivo e análises histológicas das gônadas de março de 2008 a outubro de 2009. Esse estudo mostrou que Alphestes afer é uma espécie hermafrodita diândrica. A mudança de sexo seguiu o modo protogínico em dois caminhos: machos primários transformados de fêmeas imaturas ou machos secundários transformados de fêmeas em repouso, maduras ou esgotados. A distribuição numérica por classe de tamanho indicou que fêmeas de 11-18 cm L T foram imaturas; fêmeas de 16-25 cm L T e machos de 12-22 cm L T foram de vários estádios de desenvolvimento gonadal. Indivíduos identificados como imaturos bissexuais e transicionais (ambos apresentando tecido ovariano e espermático) foram de 16-24 cm L T de comprimento. O tamanho de primeira maturação da fêmea foi 18 cm L T e do macho foi 12 cm L T. Alphestes afer mostrou desova múltipla, com período de desova de agosto a dezembro de 2008 e de agosto a outubro de 2009. A proporção sexual (fêmeas: machos) em 2008 e 2009 foi 0,94:1 durante os meses de desova. Machos foram menores que as fêmeas, alcançando o tamanho máximo de 22 cm L T comparados ao tamanho máximo de 25 cm L T das fêmeas observadas. Machos tiveram o rank de competição espermática alto (3,8) sugerindo intensa competição espermática, o que é uma possível indicação da mudança na estrutura do grupo de acasalamento de desova em pares para desova em grupo. A presença de machos pequenos com alto índice de competição espermática sugere que esta espécie, enquanto retém o padrão protogínico, possui uma estratégia reprodutiva similar aos epinefelídeos gonocoristas.


Subject(s)
Animals , Fishes/anatomy & histology , Disorders of Sex Development/surgery , Disorders of Sex Development/genetics , Disorders of Sex Development/veterinary , Sexual Maturation
13.
Comun. ciênc. saúde ; 22(1): 41-50, 2011. tab
Article in Portuguese | LILACS | ID: lil-685834

ABSTRACT

Devido à importância do balanço hídrico para os recém-nascidos com baixo peso e ao elevado índice de nascimento de uma amostra de um Hospital Público de Brasília, foi analisado 108 balanços hídricos desses recém-nascidos de baixo peso internados na Unidade de terapia intensiva neonatal desse hospital em dezembro de 2010, a fim de identificar osprofissionais responsáveis pelo registro, conhecer a importância dada por eles ao balanço hídrico e identificar possíveis lacunas na realização desse cuidado. Para isso foram entrevistados os profissionais de enfermagem que trabalham nesse setor e feita à análise dos impressos para o balanço hídrico dos recém-nascidos com baixo peso nesse período. Dessa forma, verificou-se que há um despreparo da equipe de enfermagem, por isso é importante que se desenvolva ações de educação continuada, e incentivo à participação da equipe na reformulação de um impresso para balanço hídrico de fácil manuseio com reavaliação periódica do mesmo.


Given the importance of water balance for newborns with low weight and high birth rate of a sample of a public hospital in Brasilia, was analyzed 108 water balance of these infants low birth weight infants in neonatal intensive care unit of hospital in December 2010 in order toidentify the individuals responsible for registration, know the importance given by them to the water balance and identify possible gaps in the implementation of this care. Were interviewed nursing professionalsworking in this sector and made the analysis of the forms to the water balance of newborns with low birth weight in this period. Thus, it was found that there is a lack of preparation of nursing staff, so it is important to develop actions for continuing education, and encouraging staff participation in the reformulation of a water balance printed for easy handling with periodic re-evaluation of it.


Subject(s)
Humans , Infant, Newborn , Infant, Premature , Knowledge , Nursing, Team , Hydrologic Balance
14.
IUBMB Life ; 61(1): 6-17, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18949818

ABSTRACT

Luciferase is a general term for enzymes catalyzing visible light emission by living organisms (bioluminescence). The studies carried out with Photinus pyralis (firefly) luciferase allowed the discovery of the reaction leading to light production. It can be regarded as a two-step process: the first corresponds to the reaction of luciferase's substrate, luciferin (LH(2)), with ATP-Mg(2+) generating inorganic pyrophosphate and an intermediate luciferyl-adenylate (LH(2)-AMP); the second is the oxidation and decarboxylation of LH(2)-AMP to oxyluciferin, the light emitter, producing CO(2), AMP, and photons of yellow-green light (550- 570 nm). In a dark reaction LH(2)-AMP is oxidized to dehydroluciferyl-adenylate (L-AMP). Luciferase also shows acyl-coenzyme A synthetase activity, which leads to the formation of dehydroluciferyl-coenzyme A (L-CoA), luciferyl-coenzyme A (LH(2)-CoA), and fatty acyl-CoAs. Moreover luciferase catalyzes the synthesis of dinucleoside polyphosphates from nucleosides with at least a 3'-phosphate chain plus an intact terminal pyrophosphate moiety. The LH(2) stereospecificity is a particular feature of the bioluminescent reaction where each isomer, D-LH(2) or L-LH(2), has a specific function. Practical applications of the luciferase system, either in its native form or with engineered proteins, encloses the analytical assay of metabolites like ATP and molecular biology studies with luc as a reporter gene, including the most recent and increasing field of bioimaging.


Subject(s)
Fireflies/metabolism , Luciferases/metabolism , Luminescent Proteins/metabolism , Models, Molecular , Acyl Coenzyme A/metabolism , Animals , Catalysis , Kinetics , Molecular Structure
15.
Talanta ; 77(4): 1497-503, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-19084670

ABSTRACT

Two new methods for inorganic pyrophosphate (PPi) quantification are described. They are based on the enzymatic conversion of PPi into ATP by firefly luciferase (Luc, E.C. 1.13.12.7) in the presence of dehydroluciferyl-adenylate (L-AMP) followed by the determination of ATP by one of two different procedures, either UV-monitored (260 nm) ion-pair-HPLC (IP-HPLC) (method A) or luciferase-dependent bioluminescence in the presence of its substrate, firefly luciferin (D-LH(2)) (method B). These methods were subjected to optimization using experimental design methodologies to obtain optimum values for the selected factors: method A-incubation time (t(inc)=15 min), inactivation time of the enzyme (t(inac)=2 min), pH of the reaction mixture (pH 7.50) and the concentrations of L-AMP ([L-AMP]=40 microM) and luciferase ([Luc]=0.1 microM); method B-concentrations of L-AMP ([L-AMP]=2 microM), luciferase ([Luc]=50 nM) and luciferin ([LH(2)]=30 microM). Method A has a linear response over the range of 0.1-20 microM of PPi, with a limit of detection (LOD) of 0.5 microM and a limit of quantitation (LOQ) of 1.8 microM. Precision, expressed as relative standard deviation (R.S.D.), is 7.4% at 1 microM PPi and 5.9% at 8 microM PPi. Method B has a linear response over the range of 0.75-6.0 microM of PPi, with LOD and LOQ of 0.624 and 2.23 microM, respectively, and a R.S.D. of 5.1% at 2.5 microM PPi and 4.9% at 5 microM PPi. Under optimized conditions sensitive and robust methods can be obtained for the analysis of PPi impurities in commercial nucleotides and tripolyphosphate (P(3)).


Subject(s)
Adenosine Triphosphate/chemistry , Chromatography/methods , Diphosphates/analysis , Luciferases/chemistry , Animals , Calibration , Chromatography/instrumentation , Fireflies , Hydrogen-Ion Concentration , Ions , Luminescence , Models, Chemical , Models, Theoretical , Nucleotides/chemistry , Reproducibility of Results , Time Factors
16.
Anal Bioanal Chem ; 391(6): 2161-8, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18437362

ABSTRACT

A new bioluminescent method for coenzyme A (CoA) quantification is described. It is based on the enzymatic conversion of dehydroluciferyl-adenylate (L-AMP) into dehydroluciferyl-coenzyme A (L-CoA) by firefly luciferase (E.C. 1.13.12.7) (LUC), which causes a flash of light that can be measured in a luminometer. The method was subjected to optimization using experimental design methodologies to obtain optimum values for the concentrations of L-AMP ([L-AMP]), luciferase ([LUC]), ATP ([ATP]) and luciferin ([LH(2)]). This method has a linear response over the range of 0.25-4 microM of CoA, with a limit of detection (LOD) of 0.24 microM and a limit of quantification (LOQ) of 0.80 microM. The assay has a relative standard deviation of about 7%. By coupling this optimized procedure to bioluminescent detection, a sensible and robust method can be obtained for the analysis of CoA.


Subject(s)
Coenzyme A/analysis , Luminescent Measurements/methods , Adenosine Monophosphate , Adenosine Triphosphate , Firefly Luciferin , Luciferases
17.
Braz. j. microbiol ; 38(3): 538-543, July-Sept. 2007. ilus, graf, tab
Article in English | LILACS | ID: lil-464786

ABSTRACT

The objectives of this work were to verify the capability of Staphylococcus aureus of forming bio-film on stainless steel and glass surfaces; to evaluate the efficiency of sodium dichloroisocyanurate, hydrogen peroxide and peracetic acid in inactivating Staphylococcus aureus cells adhered onto these surfaces; and to visualize biofilm development by scanning electron microscopy before and after sanitizer treatment. The surfaces studied consisted of 10x20mm chips immersed in Petri dishes containing BHI broth inoculated with S. aureus ATCC 25923. Biofilm formation was observed after 15-day incubation, when the cells were removed using the swab technique, followed by Baird Parker agar plating. Also, the efficiency of the chemical sanitizers on the chip surfaces was tested and the non-removed cells were counted on the Baird-Parker agar. After biofilm formation and use of sanitizers, the chips were respectively observed by scanning electronic microscopy following a pre-existing protocol. The obtained results showed biofilm formation on both surfaces, with bacterial count in the order of 10(7) CFU/cm² on and 10(8) CFU/cm² on stainless steel and glass surfaces, respectively. Peracetic acid was the most efficient in removing adhered cells, presenting 5.26 and 4.5 decimal reduction for adhered cells on stainless steel and glass surfaces, respectively.


Os objetivos deste trabalho foram verificar a capacidade de Staphylococcus aureus formar biofilme nas superfícies de aço inoxidável e vidro, avaliar a eficiência do dicloroisocianurato de sódio, peróxido de hidrogênio e ácido peracético na inativação de células de S. aureus aderidas e visualização por microscopia eletrônica de varredura, o desenvolvimento antes e depois do tratamento das superfícies com os sanificantes. As superfícies foram cupons 10x200mm imersos em placas de Petri contendo caldo BHI inoculado com cultura de Staphylococcus aureus ATCC 25923. A formação de biofilme foi observada após 15 dias de incubação, quando as células foram removidas pela técnica do suabe, seguiram-se diluições seriadas e plaqueamento em ágar Baird Parker. Testou-se a eficiência dos sanificantes nas superfícies dos cupons e as células não removidas foram enumeradas no ágar Baird Parker. Os cupons após formação do biofilme e cupons sanificados foram observados pela microscopia eletrônica de varredura seguindo um protocolo. Os resultados obtidos indicaram a formação de biofilme em ambas superfícies, com contagens bacterianas na ordem de 10(7) UFC/cm² e 10(8) UFC/cm² nas superfícies de aço inoxidável e vidro, respectivamente. Dentre os sanificantes estudados o ácido peracético apresentou uma eficiência maior na remoção das células aderidas, apresentado redução decimal de 5,26 e 4,5 para as células aderidas na superfície de vidro e aço inoxidável.


Subject(s)
Biofilms , Glass , In Vitro Techniques , Stainless Steel , Staphylococcus aureus , Methods , Microscopy, Electron, Scanning
18.
Hig. aliment ; 18(126/127): 98-102, nov.-dez. 2004. tab, graf
Article in Portuguese | LILACS | ID: lil-401043

ABSTRACT

Alimentos doces, principalmente tortas, são muito apreciados pela combinação de diferentes ingredientes, conferindo-lhes flavours especiais. Porém, a intensa manipulação a que são submetidos, potencializa sua participação como importante agente causal de surtos de doenças veiculadas por alimentos. Além disso, sua qualidade higiênico-sanitária relaciona-se diretamente às formas de armazenamento e condições de comercialização, que podem influenciar, significativamente, nos índices microbiológicos. O objetivo deste trabalho foi avaliar as condições higiênico-sanitárias de tortas doces comercializadas no município de Lavras, Minas Gerais. Foram realizadas análises de coliformes totais e termorresistentes, Clostrídios sulfito redutores, Staphylococcus coagulase positiva, Bacillus cereus e Salmonella sp em 20 amostras adquiridas no comércio local. É satisfatória a ausência de Salmonella, Clostrídiso sulfito redutores e as baixas contagens de Bacillus cereus encontrados nas amostras; porém, a alta contagem de Staphylococcus coagulase positivos em algumas amostras pode indicar falta de higiene na elaboração, armazenamento e comercialização das tortas, existindo o potencial risco de produção de toxina estafilocócica, passível de colocar em risco a saúde dos consumidores.


Subject(s)
Candy , Consumer Product Safety , Food Hygiene , Food Quality
19.
Braz. arch. biol. technol ; 47(5): 799-804, Sept. 2004. graf
Article in English | LILACS | ID: lil-388765

ABSTRACT

O sêmen das seguintes espécies de Characiformes neotropicais foi testado para armazenamento em ambiente resfriado: Brycon lundii, Piaractus mesopotamicus, Leporinus elongatus, Leporinus friderici, Prochilodus lineatus e Prochilodus marggravii. Amostras de sêmen, obtidas por massagem da parede celômica, foram armazenadas em saco plástico com ar ou oxigênio ou em tubo plástico com ar, e mantidas resfriadas entre 1,7-4,9º C. A taxa de motilidade espermática foi estimada usando-se NaCl 50 mM como solução ativadora. O sêmen com menor duração de viabilidade (7 h) foi o de L. friderici, quando a taxa de motilidade espermática alcançou aproximadamente 30%, enquanto que o de maior duração (20 h) foi o de P. lineatus. A fertilização de ovócitos utilizando sêmen refrigerado por 8 h de Prochilodus marggravii produziu 88-90% de embriões viáveis. O método de armazenamento desenvolvido neste trabalho tem aplicações práticas, especialmente no manejo reprodutivo de peixes em estações de piscicultura.

20.
Rev. odontol. UNESP ; 32(1): 67-73, jan.-jun. 2003. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-391632

ABSTRACT

Camundongos fêmeas receberam injeção de 30 mg/kg de cloreto de níquel no 10° dia de gestação. Os animais foram sacrificados no 16° dia de gestação, ao nascimento e aos 3 dias de idade. As cabeças foram incluídas em parafina, de modo a fornecerem cortes frontais e corados para análise histológica. Os resultados mostraram, no 16° dia de gestação, semelhança nas estruturas morfológicas dos órgãos dentais dos animais controles e tratados e atraso na formação óssea do processo alveolar. Nos demais períodos de observação não houve diferenças observáveis tanto no desenvolvimento dos germes dentais quanto do processo alveolar entre os dois grupos de animais. Concluiu-se que o cloreto de níquel atrasa, reversivelmente, o desenvolvimento e a ossificação do processo alveolar, sem interferir no desenvolvimento dos germes dentais


Subject(s)
Tooth Germ , Alveolar Process
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