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1.
Life Sci ; 228: 305-315, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31047898

RESUMO

Silymarin, an extract from Silybum marianum (milk thistle) containing a standardized mixture of flavonolignans that ameliorates some types of liver disease and, more recently, kidney damage, could be used for the ROS-scavenging effect of these antioxidants. Furthermore, contrast-induced nephropathy (CIN) is an iatrogenic impairment of renal function in patients subjected to angiographic procedures for which there is not yet a successful preventative treatment. Recent evidence has shown that this event is related to tubular/vascular injury activated mainly by oxidative stress. However, whether this bioavailable and pharmacologically safe extract protects against CIN is not clear. We proposed to evaluate the possible protective role of the antioxidant silymarin in an experimental model of CIN. Adult male Swiss mice were separated into 6 groups and pretreated orally with silymarin (50, 200 and 300 mg/kg), N-acetylcysteine (200 mg/kg) or vehicle for 5 days before the CIN and control groups. Renal function was analyzed by plasma creatinine, urea and cystatin C levels. Additionally, blood reactive oxygen species (ROS) were evaluated using ROS bioavailability, protein oxidation and DNA damage. Renal oxidative damage was evaluated using apoptosis/cell viability assays and histological analysis. We showed that silymarin preserved renal function and decreased systemic and renal oxidative damage (antigenotoxic and antiapoptotic properties, respectively) in a dose-dependent manner and was superior to conventional treatment with N-acetylcysteine. Histologically, silymarin treatment also had beneficial effects on renal glomerular and tubular injuries. Therefore, silymarin prophylaxis may be an interesting strategy for the prevention of CIN.


Assuntos
Meios de Contraste/efeitos adversos , Rim/efeitos dos fármacos , Nefrite/induzido quimicamente , Nefrite/prevenção & controle , Substâncias Protetoras/uso terapêutico , Silimarina/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Cardo Mariano/química , Nefrite/metabolismo , Nefrite/patologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/química , Silimarina/química
2.
Front Microbiol ; 9: 1945, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30174668

RESUMO

Fast detection and enumeration of Oenococcus oeni in winemaking are necessary to determine whether malolactic fermentation (MLF) is likely to be performed or not and to decide if the use of a commercial starter is needed. In other wines, however, performing MLF can be detrimental for wine and should be avoided. The traditional identification and quantification of this bacteria using culture-dependent techniques in wine-related matrices require up to 14 days to yield results, which can be a very long time to perform possible enological operations. Loop-mediated isothermal amplification (LAMP) is a novel culture-independent technique that amplifies nucleic acid sequences under isothermal conditions with high specificity and efficiency in less than 1 h with inexpensive equipment. We designed LAMP primers for the specific detection and quantification of O. oeni cells. The developed LAMP method allows O. oeni to be detected directly from both grape musts and wines within 1 h from the time that the LAMP reaction begins, and without DNA extraction and purification requirements. The high sensitivity of LAMP methodology is achieved by previous mechanical cells lysis with no further purification by detecting one single cell per reaction in culture media, and in white/red grape musts and wines by avoiding reaction inhibition by ethanol, polyphenols, and other wine inhibitors. Cells can be concentrated prior to the LAMP reaction to further increase this sensitivity. Moreover, the LAMP method does not require expensive equipment and can be easily operated. The developed method is both economic and fast and offers high sensitivity and specificity.

3.
J Med Microbiol ; 67(3): 314-324, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458667

RESUMO

PURPOSE: Virulent genotypes of Helicobacter pylori vacA s1m1/cagA+/babA2+ have been associated with severe gastric diseases. VacA, CagA and BabA are polymorphic proteins, and their association with the disease is allele-dependent. The aims of this work were: (i) to determine the prevalence of H. pylori by type of chronic gastritis; (ii) to describe the frequency of cagA, babA2 and vacA genotypes in strains from patients with different types of chronic gastritis; (iii) to characterize the variable region of cagA alleles. METHODOLOGY: A total of 164 patients with chronic gastritis were studied. Altogether, 50 H. pylori strains were isolated, and the status of cagA, babA2 and vacA genotypes was examined by PCR. cagA EPIYA segment identification was performed using PCR and sequencing of cagA fragments of six randomly selected strains.Results/Key findings. The overall prevalence of H. pylori was 30.5 %. Eighty percent of the isolated strains were vacA s1m1, and the cagA and babA2 genes were detected in 74 and 32 % of the strains, respectively. The most frequent genotypes were vacA s1m1/cagA+/babA2- and vacA s1m1/cagA+/babA2+, with 40 % (20/50) and 28 % (14/50), respectively. In cagA+, the most frequent EPIYA motif was -ABC (78.4 %), and EPIYA-ABCC and -ABCCC motifs were found in 10.8 % of the strains. A modified EPIYT-B motif was found in 66.6 % of the sequenced strains. CONCLUSION: H. pylori strains carrying vacA s1m1, cagA+ and babA2- genotypes were the most prevalent in patients with chronic gastritis from the south of Mexico. In the cagA+ strains, the EPIYA-ABC motif was the most common.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Gastrite/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Adulto , Idoso , Alelos , Doença Crônica/epidemiologia , Feminino , Gastrite/epidemiologia , Gastroscopia , Genótipo , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estômago/microbiologia , Estômago/patologia
4.
IEEE Trans Haptics ; 11(1): 61-72, 2018 Jan-Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28922126

RESUMO

Many tasks involve the fine manipulation of objects despite limited visual feedback. In such scenarios, tactile and proprioceptive feedback can be leveraged for task completion. We present an approach for real-time haptic perception and decision-making for a haptics-driven, functional contour-following task: the closure of a ziplock bag. This task is challenging for robots because the bag is deformable, transparent, and visually occluded by artificial fingertip sensors that are also compliant. A deep neural net classifier was trained to estimate the state of a zipper within a robot's pinch grasp. A Contextual Multi-Armed Bandit (C-MAB) reinforcement learning algorithm was implemented to maximize cumulative rewards by balancing exploration versus exploitation of the state-action space. The C-MAB learner outperformed a benchmark Q-learner by more efficiently exploring the state-action space while learning a hard-to-code task. The learned C-MAB policy was tested with novel ziplock bag scenarios and contours (wire, rope). Importantly, this work contributes to the development of reinforcement learning approaches that account for limited resources such as hardware life and researcher time. As robots are used to perform complex, physically interactive tasks in unstructured or unmodeled environments, it becomes important to develop methods that enable efficient and effective learning with physical testbeds.

5.
Braz. arch. biol. technol ; 61: e18180052, 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-974060

RESUMO

ABSTRACT The aim of this study was to evaluate the antifungal action of ethanolic extracts of avocado seeds, by conducting two experiments in the laboratory of plant pathology of EPAMIG SUL/Lavras, MG, Brazil, in a completely randomized design with three replicates. The first consisted of the following treatments ('Breda' 3%, 'Breda' 2%, 'Margarida' 3%, 'Margarida' 2%, Control, and Ethanol) testing its inhibitory effect on two fungal species (Colletotrichum gloeosporioides and Monilinia fructicola) and the second consisted of different concentrations of extracts (0%, 0.25%, 0.50%, 0.75%, 1.0%, 1.5%, and 2.0%) on the fungus F fructicola. The evaluations were performed at three times (7, 14, and 21 days of incubation) by measurements of the mycelial diameter using a digital caliper. The data were submitted to analysis of variance and the averages were compared by Scott-Knott test at 5% probability. The results demonstrated the positive potential of the ethanolic extracts of avocado seed on the mycelial development of fungi M. fructicola and C. gloeosporioides during the evaluated days.

6.
Braspen J ; 33(2): 152-157, 2018. tab
Artigo em Português | LILACS | ID: biblio-910146

RESUMO

Introdução: Doenças hematológicas são comumente associadas ao descontrole da replicação do HIV e à consequente depleção dos linfócitos T-helper e, especial atenção merece a anemia, que é a alteração hematológica mais frequente. Objetivo: Avaliar a prevalência de anemia e relação com os dados antropométricos de portadores de HIV/AIDS que fazem tratamento em uma Casa de Assistência a pessoas com AIDS do município de Aracaju-SE. Método: Estudo observacional descritivo transversal, composto por 120 indivíduos de ambos os sexos, na faixa etária de 26 a 61 anos, no qual foi avaliada a frequência de anemia e sua associação com algumas características sociodemográficas, clínicas e antropométricas. Resultados: Foi evidenciado predomínio do sexo masculino (54,8%), com média de idade próxima aos 40 anos. A frequência de anemia foi elevada, em 50,8% da amostra. Porém, dentre as variáveis analisadas, a anemia manifestou-se independentemente da faixa etária, do gênero, do tempo de descoberta da doença ou do tipo de fármaco utilizado no tratamento da infecção estudada. Já em relação aos dados antropométricos, a anemia prevaleceu nos pacientes que apresentaram maior índice de massa corporal, maior AMBc e associação entre menor somatório de dobras cutâneas e a ocorrência da anemia. Conclusão: A alta prevalência de anemia na amostra analisada é uma informação preocupante, visto que esse distúrbio tem sido associado à piora da condição clínica e está relacionada ao risco aumentado de óbitos em pacientes infectados pelo HIV/AIDS.


Assuntos
Humanos , Masculino , Feminino , Síndrome de Imunodeficiência Adquirida , Antropometria , Doenças Hematológicas , Avaliação Nutricional , Doenças Sexualmente Transmissíveis
7.
Beilstein J Org Chem ; 13: 2596-2602, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29259669

RESUMO

Isocyanide-based multicomponent reactions (IMCRs) allow the construction of relatively complex molecules through a one-pot synthesis. The combination of IMCRs in a consecutive or sequential fashion further extends the complexity of the molecules obtained. Herein, we report the efficient application of this approach to the synthesis of acylhydrazines bearing 1,5-disubstituted tetrazoles. Our strategy was accomplished in only three steps: first, a one-pot hydrazino-Ugi-azide four-component reaction; second a hydrazinolysis and finally an additional hydrazino-Ugi-azide reaction. This sequence provides the title compounds in moderate to excellent yields. The products synthesized herein contain functional groups within their structures that can be easily modified to obtain new acylhydrazino 1,5-disubstituted tetrazoles.

8.
Int J Food Microbiol ; 261: 25-34, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28889055

RESUMO

A novel quantitative PCR assay called Cells-qPCR has been developed for the rapid detection and quantification of yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) directly from grape must and wine that does not require DNA extraction. The assay was tested on Brettanomyces bruxellensis, Saccharomyces cerevisiae, Lactobacillus plantarum, Oenococcus oeni, Acetobacter aceti and Gluconobacter oxydans in culture media, and in white and red grape musts and wines. Standard curves were constructed from DNA and cells for the six target species in all the matrices. Good efficiencies were obtained for both when comparing DNA and cells standard curves. No reaction inhibition was observed between matrices for each species. Cells quantification was linear over a range of cell concentrations (7, 5 or 4 orders of magnitude) and detected as few as one cell per reaction in all the matrices. The developed Cells-qPCR assay is a robust, reliable, fast and specific method to detect and quantify different yeasts, LAB and AAB species in grape must and wine that avoids DNA extraction and overcomes the presence of inhibitors like polyphenols and ethanol.


Assuntos
Acetobacter/isolamento & purificação , DNA Bacteriano/genética , DNA Fúngico/genética , Lactobacillus plantarum/isolamento & purificação , Oenococcus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Vitis/microbiologia , Vinho/microbiologia , Leveduras/isolamento & purificação , Acetobacter/genética , Acetobacter/metabolismo , DNA Bacteriano/isolamento & purificação , DNA Fúngico/isolamento & purificação , Fermentação , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Oenococcus/genética , Oenococcus/metabolismo , Leveduras/genética , Leveduras/metabolismo
9.
Invest. clín ; 58(3): 284-308, sep. 2017. ilus, tab
Artigo em Espanhol | LILACS-Express | ID: biblio-893542

RESUMO

La obesidad es una enfermedad compleja y multifactorial, caracterizada por un aumento de grasa corporal que puede ser ocasionado por un desequilibrio entre la ingesta de alimentos y el gasto energético. En el proceso de aumento de peso intervienen factores como la susceptibilidad genética, factores ambientales y el estilo de vida. Está bien documentado que la obesidad aumenta el riesgo de padecer numerosas enfermedades y trastornos metabólicos como la resistencia a la insulina, diabetes tipo 2, hipercolesterolemia, enfermedades cardiovasculares, hígado graso, inflamación de bajo grado, algunos tipos de cáncer y trastornos sicológicos. Debido al incremento de la obesidad y sus comorbilidades en los últimos años en la población mundial, los gastos médicos erogados para su tratamiento representan un problema grave para los sistemas de salud pública. El análisis proteómico a gran escala, es una herramienta potente y prometedora para el descubrimiento de biomarcadores tempranos y para la comprensión de los mecanismos moleculares que subyacen a las alteraciones metabólicas asociadas con la obesidad. No obstante, es imprescindible considerar las limitaciones técnicas y el análisis e interpretación de los hallazgos proteómicos, para avanzar en la comprensión funcional integral de la dinámica del proteoma ligado a la obesidad. Adicionalmente, los abordajes con un enfoque proteómico, permitirán el desarrollo de nuevas terapias preventivas, así como el descubrimiento de agentes terapéuticos potenciales en el tratamiento de disfunciones metabólicas. El objetivo de esta revisión es analizar las contribuciones más recientes de la proteómica en la búsqueda de biomarcadores relacionados con la obesidad.


Obesity is a complex and multifactorial disease characterized by an increase in body fat that can be caused by an imbalance between food intake and energy expenditure. In the process of weight gain, factors such as genetic susceptibility, environmental factors and lifestyle are involved. It is well documented that obesity increases the risk of numerous diseases and metabolic disorders such as insulin resistance, type 2 diabetes, hypercholesterolemia, cardiovascular disease, fatty liver, low grade inflammation, some types of cancer and psychological disorders. Due to the increase in obesity and its comorbidities in recent years at the global level, medical expenses incurred for its treatment represent a serious problem for public health systems. Large-scale proteomic analysis is a powerful and promising tool for the discovery of early biomarkers and for the understanding of the molecular mechanisms underlying the metabolic alterations associated with obesity. Nevertheless, it is essential to consider the technical limitations and the analysis and interpretation of the proteomic findings, to advance in the integral functional understanding of the dynamics of the proteome linked to obesity. In addition, approaches with a proteomic viewpoint will allow the development of new preventive therapies, as well as the discovery of potential therapeutic agents in the treatment of metabolic dysfunctions. The aim of this review is to analyze the most recent contributions of proteomics in the search for biomarkers related to obesity.

10.
PLoS One ; 12(3): e0173285, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28278272

RESUMO

Klebsiella pneumoniae is a common opportunistic pathogen causing nosocomial infections. One of the main virulence determinants of K. pneumoniae is the type 3 pilus (T3P). T3P helps the bacterial interaction to both abiotic and biotic surfaces and it is crucial for the biofilm formation. T3P is genetically organized in three transcriptional units: the mrkABCDF polycistronic operon, the mrkHI bicistronic operon and the mrkJ gene. MrkH is a regulatory protein encoded in the mrkHI operon, which positively regulates the mrkA pilin gene and its own expression. In contrast, the H-NS nucleoid protein represses the transcriptional expression of T3P. Here we reported that MrkH and H-NS positively and negatively regulate mrkJ expression, respectively, by binding to the promoter of mrkJ. MrkH protein recognized a sequence located at position -63.5 relative to the transcriptional start site of mrkJ gene. Interestingly, our results show that, in addition to its known function as classic transcriptional activator, MrkH also positively controls the expression of mrk genes by acting as an anti-repressor of H-NS; moreover, our results support the notion that high levels of MrkH repress T3P expression. Our data provide new insights about the complex regulatory role of the MrkH protein on the transcriptional control of T3P in K. pneumoniae.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Regulação Bacteriana da Expressão Gênica , Infecções por Klebsiella/genética , Klebsiella pneumoniae/genética , Óperon/genética , Proteínas Repressoras/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Infecções por Klebsiella/metabolismo , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética
11.
J Microbiol Biotechnol ; 27(1): 179-188, 2017 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-27713214

RESUMO

White-rot basidiomycetes are the organisms that decompose lignin most efficiently, and Trametes villosa is a promising species for ligninolytic enzyme production. There are several publications on T. villosa applications for lignin degradation regarding the expression and secretion of laccase and manganese peroxidase (MnP) but no reports on the identification and characterization of lignin peroxidase (LiP), a relevant enzyme for the efficient breakdown of lignin. The object of this study was to identify and partially characterize, for the first time, gDNA, mRNA, and the corresponding lignin peroxidase (TvLiP) protein from T. villosa strain CCMB561 from the Brazilian semiarid region. The presence of ligninolytic enzymes produced by this strain grown in inducer media was qualitatively and quantitatively analyzed by spectrophotometry, qPCR, and dye fading using Remazol Brilliant Blue R. The spectrophotometric analysis showed that LiP activity was higher than that of MnP. The greatest LiP expression as measured by qPCR occurred on the 7th day, and the ABSA medium (agar, sugarcane bagasse, and ammonium sulfate) was the best that favored LiP expression. The amplification of the TvLiP gene median region covering approximately 50% of the T. versicolor LPGIV gene (87% identity); the presence of Trp199, Leu115, Asp193, Trp199, and Ala203 in the translated amplicon of the T. villosa mRNA; and the close phylogenetic relationship between TvLiP and T. versicolor LiP all indicate that the target enzyme is a lignin peroxidase. Therefore, T. villosa CCMB561 has great potential for use as a LiP, MnP, and Lac producer for industrial applications.

12.
Nutr. clín. diet. hosp ; 37(2): 12-20, 2017. tab
Artigo em Inglês | IBECS | ID: ibc-165427

RESUMO

Introduction: HIV-positive patient lipodystrophy is the redistribution of body fat and may be accompanied by cardiovascular and metabolic disorders. Objective: Was to investigate the prevalence of lipodystrophy in adults infected with HIV, as well as its relationship with cardiovascular risk factors and metabolic syndrome. Methodology: Cross-sectional study with HIV-positive adult patients taking antiretroviral medication. Data were collected through a questionnaire and through medical records (viral RNA, CD4, blood glucose, LDL, HDL, triglycerides). In addition to anthropometry (waist circumference, body weight, height and BMI). Results: 120 people studied among them (50.8%) had lipodystrophy, the highest prevalence of lipodystrophy (52.1%) occurred in males and the most widely used medication was the NRTI + PI (24,2%). The lipodystrophy was more frequent in patients with cardiovascular disease (68.4%), metabolic syndrome (59.3%) and those with increased waist circumference (55.1%). Significant differences (p<0.05) among the analyzed subgroups (with or without lipodystrophy) occurred with triglycerides, LDL and glucose levels. Discussion: The use of HAART tends to improve the condition of immunity and is associated with the onset of lipodystrophy. This also associated with excess weight and fat accumulation predisposes to the development of metabolic syndrome. Conclusion: the study contributed to direct the focus and attention profile of specialized services for HIV/AIDS (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Síndrome Metabólica/epidemiologia , Infecções por HIV/complicações , Doenças Cardiovasculares/epidemiologia , Síndrome de Lipodistrofia Associada ao HIV/complicações , Fatores de Risco , Composição Corporal , Tecido Adiposo/fisiopatologia , Estudos Transversais
13.
Artigo em Inglês | MEDLINE | ID: mdl-27995126

RESUMO

The addition of tactile and proprioceptive feedback to neuroprosthetic limbs is expected to significantly improve the control of these devices. Intracortical microstimulation (ICMS) of somatosensory cortex is a promising method of delivering this sensory feedback. To date, the main focus of somatosensory ICMS studies has been to deliver discriminable signals, corresponding to varying intensity, to a single location in cortex. However, multiple independent and simultaneous streams of sensory information will need to be encoded by ICMS to provide functionally relevant feedback for a neuroprosthetic limb (e.g., encoding contact events and pressure on multiple digits). In this study, we evaluated the ability of an awake, behaving non-human primate (Macaca mulatta) to discriminate ICMS stimuli delivered on multiple electrodes spaced within somatosensory cortex. We delivered serial stimulation on single electrodes to evaluate the discriminability of sensations corresponding to ICMS of distinct cortical locations. Additionally, we delivered trains of multichannel stimulation, derived from a tactile sensor, synchronously across multiple electrodes. Our results indicate that discrimination of multiple ICMS stimuli is a challenging task, but that discriminable sensory percepts can be elicited by both single and multichannel ICMS on electrodes spaced within somatosensory cortex.

14.
Int. microbiol ; 19(4): 209-215, dic. 2016. tab
Artigo em Inglês | IBECS | ID: ibc-162897

RESUMO

Escherichia coli is the main cause of urinary tract infections (UTI) in ambulatory patients, especially strains belonging to the B2 phylogenetic group and ST131 clonal group. Antibiotic treatment is usually administered empirically; however, it is not always effective due to bacterial multidrug resistance and the production of extended spectrum β-lactamases (ESBLs). The aim of this study was to characterize E. coli clinical isolates from patients with UTI in a community of the State of Guerrero, Mexico. From January to August 2014, 134 clinical isolates of E. coli were recovered. Strain identification and antibiotic susceptibility were performed using the Vitek automated system. Phylogenetic and O25b-ST13 groups were determined by multiple PCR. Identification of the blaCTX-M, blaTEM, and blaSHV genes was performed by conventional PCR. We found that over 50% of the isolates were resistant to betalactams and quinolones, while 0 to 33% were resistant to aminoglycosides and nitrofurans, and 56.49% of the strains were ESBL producers. B2 phylogenetic group was the most predominant (43%) compared to the other groups. The prevalence of bla genes was: blaCTX-M 64.3%, blaSHV 41.4%, and blaTEM 54.3%. These results show a high percentage (55%) of multidrug-resistant strains isolated from UTI patients from the community in the city of Chilpancingo, Guerrero, Mexico (AU)


No disponible


Assuntos
Humanos , Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Infecções Urinárias/microbiologia , México/epidemiologia , Colimetria/métodos , Farmacorresistência Bacteriana Múltipla , Urina/microbiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-27818950

RESUMO

Enteropathogenic Escherichia coli and enterohemorrhagic E. coli are diarrheagenic bacterial human pathogens that cause severe gastroenteritis. These enteric pathotypes, together with the mouse pathogen Citrobacter rodentium, belong to the family of attaching and effacing pathogens that form a distinctive histological lesion in the intestinal epithelium. The virulence of these bacteria depends on a type III secretion system (T3SS), which mediates the translocation of effector proteins from the bacterial cytosol into the infected cells. The core architecture of the T3SS consists of a multi-ring basal body embedded in the bacterial membranes, a periplasmic inner rod, a transmembrane export apparatus in the inner membrane, and cytosolic components including an ATPase complex and the C-ring. In addition, two distinct hollow appendages are assembled on the extracellular face of the basal body creating a channel for protein secretion: an approximately 23 nm needle, and a filament that extends up to 600 nm. This filamentous structure allows these pathogens to get through the host cells mucus barrier. Upon contact with the target cell, a translocation pore is assembled in the host membrane through which the effector proteins are injected. Assembly of the T3SS is strictly regulated to ensure proper timing of substrate secretion. The different type III substrates coexist in the bacterial cytoplasm, and their hierarchical secretion is determined by specialized chaperones in coordination with two molecular switches and the so-called sorting platform. In this review, we present recent advances in the understanding of the T3SS in attaching and effacing pathogens.


Assuntos
Citrobacter rodentium/metabolismo , Escherichia coli Êntero-Hemorrágica/metabolismo , Escherichia coli Enteropatogênica/metabolismo , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/metabolismo , Animais , Citrobacter rodentium/genética , Citrobacter rodentium/patogenicidade , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/patogenicidade , Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/patogenicidade , Humanos , Camundongos , Multimerização Proteica , Transporte Proteico , Sistemas de Secreção Tipo III/química , Sistemas de Secreção Tipo III/genética
16.
Am Surg ; 82(10): 872-875, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27779963

RESUMO

With changes in work hour limitations, there is an increasing need for objective determination of technical proficiency. Electromagnetic hand-motion analysis has previously shown only time to completion and number of movements to correlation with expertise. The present study was undertaken to evaluate the efficacy of hand-motion-tracking analysis in determining surgical skill proficiency. A nine-degree-of-freedom sensor was used and mounted on the superior aspect of a needle driver. A one-way analysis of variance and Welch's t test were performed to evaluate significance between subjects. Four Novices, four Trainees, and three Experts performed a large vessel patch anastomosis on a phantom tissue. Path length, total number of movements, absolute velocity, and total time were analyzed between groups. Compared to the Novices, Expert subjects exhibited significantly decreased total number of movements, decreased instrument path length, and decreased total time to complete tasks. There were no significant differences found in absolute velocity between groups. In this pilot study, we have identified significant differences in patterns of motion between Novice and Expert subjects. These data warrant further analysis for its predictive value in larger cohorts at different levels of training and may be a useful tool in competence-based training paradigms in the future.


Assuntos
Competência Clínica , Mãos/fisiologia , Destreza Motora/fisiologia , Anastomose Cirúrgica/métodos , Cirurgia Geral/métodos , Humanos , Internato e Residência/estatística & dados numéricos , Corpo Clínico Hospitalar/estatística & dados numéricos , Movimento (Física) , Amostragem , Estudantes de Medicina/estatística & dados numéricos , Análise e Desempenho de Tarefas
17.
Eur J Ophthalmol ; 26(5): 505-9, 2016 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26776699

RESUMO

PURPOSE: To validate a school-based amblyopia screening program model by comparing its outcomes to those of a state-of-the-art conventional ophthalmic clinic examination in a kindergarten population of children between the ages of 4 and 5 years. METHODS: An amblyopia screening protocol, which consisted of visual acuity measurement using Lea charts, ocular alignment test, ocular motility assessment, and stereoacuity with TNO random-dot test, was performed at school in a pediatric 4- to 5-year-old population by qualified healthcare professionals. The outcomes were validated in a selected group by a conventional ophthalmologic examination performed in a fully equipped ophthalmologic center. The ophthalmologic evaluation was used to confirm whether or not children were correctly classified by the screening protocol. The sensitivity and specificity of the test model to detect amblyopia were established. RESULTS: A total of 18,587 4- to 5-year-old children were subjected to the amblyopia screening program during the 2010-2011 school year. A population of 100 children were selected for the ophthalmologic validation screening. A sensitivity of 89.3%, specificity of 93.1%, positive predictive value of 83.3%, negative predictive value of 95.7%, positive likelihood ratio of 12.86, and negative likelihood ratio of 0.12 was obtained for the amblyopia screening validation model. CONCLUSIONS: The amblyopia screening protocol model tested in this investigation shows high sensitivity and specificity in detecting high-risk cases of amblyopia compared to the standard ophthalmologic examination. This screening program may be highly relevant for amblyopia screening at schools.


Assuntos
Ambliopia/diagnóstico , Seleção Visual/normas , Pré-Escolar , Movimentos Oculares , Reações Falso-Positivas , Feminino , Humanos , Funções Verossimilhança , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Acuidade Visual/fisiologia
18.
Beilstein J Org Chem ; 12: 2865-2872, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28144359

RESUMO

Herein we describe a versatile approach for the synthesis of acylhydrazino-peptomers, a new class of peptidomimetics. The key idea in this approach is based on a simple route using a one-pot hydrazino-Ugi four-component reaction followed by a hydrazinolysis or hydrolysis reaction and subsequent hydrazino-Ugi reaction or classical Ugi reaction for the construction of acyclic acylhydrazino-peptomers. The consecutive multicomponent reactions produced a variety of acylhydrazino-peptomers in moderate to excellent yields (47-90%). These compounds are multifunctional intermediates that can be further functionalized to obtain new peptidomimetics with potential biological activity.

19.
Int Microbiol ; 19(4): 209-215, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28504818

RESUMO

Escherichia coli is the main cause of urinary tract infections (UTI) in ambulatory patients, especially strains belonging to the B2 phylogenetic group and ST131 clonal group. Antibiotic treatment is usually administered empirically; however, it is not always effective due to bacterial multidrug resistance and the production of extended spectrum ß-lactamases (ESBLs). The aim of this study was to characterize E. coli clinical isolates from patients with UTI in a community of the State of Guerrero, Mexico. From January to August 2014, 134 clinical isolates of E. coli were recovered. Strain identification and antibiotic susceptibility were performed using the Vitek automated system. Phylogenetic and O25b-ST13 groups were determined by multiple PCR. Identification of the blaCTX-M, blaTEM, and blaSHV genes was performed by conventional PCR. We found that over 50% of the isolates were resistant to betalactams and quinolones, while 0 to 33% were resistant to aminoglycosides and nitrofurans, and 56.49% of the strains were ESBL producers. B2 phylogenetic group was the most predominant (43%) compared to the other groups. The prevalence of bla genes was: blaCTX-M 64.3%, blaSHV 41.4%, and blaTEM 54.3%. These results show a high percentage (55%) of multidrug-resistant strains isolated from UTI patients from the community in the city of Chilpancingo, Guerrero, Mexico. [Int Microbiol 19(4): 209-215 (2016)].


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Filogenia , Infecções Urinárias/microbiologia , Antibacterianos , Farmacorresistência Bacteriana Múltipla , Escherichia coli/classificação , Humanos , México , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
20.
Memorandum ; 29: 133-152, out. 2015.
Artigo em Português | LILACS, Index Psicologia - Periódicos técnico-científicos | ID: biblio-914877

RESUMO

A pesquisa apresentada aqui pretendeu compreender como a experiência de militares em uma missão de paz no Haiti afetou as relações com o Outro. Como objetivo secundário, buscamos observar como os dois tempos/lócus (Haiti e Brasil) se entrecruzam nas identidades e nas representações dos militares. Trata-se de uma pesquisa qualitativa empírica. Entrevistas narrativas e a técnica Photovoice foram utilizadas na produção de dados. Observou-se o entrecruzamento dos dois tempos/lócus nas identidades e representações do militar. Transformação nas identidades e nas representações também foram identificadas.(AU)


The research presented here sought to understand how the experience of soldiers on a mission of peace in Haiti affected relations with the Other. As a secondary objective, we sought to observe how time/locus (Haiti and Brazil) intersects with the identities and representations of the military. This is an empirical qualitative research. Photovoice technique and narrative interviews were used to collect data. The interweaving of the time/locus with the identities and representations of the military were onserved. Transformation on identities and representations was also identified.(AU)


Assuntos
Psicologia
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