Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 962
Filtrar
1.
Semina cienc. biol. saude ; 45(2): 113-126, jul./dez. 2024. Tab, Ilus
Artículo en Portugués | LILACS | ID: biblio-1513051

RESUMEN

A síndrome respiratória aguda grave (SRAG) é caracterizada por sintomas de febre alta, tosse e dispneia, e, na maioria dos casos, relacionada a uma quantidade reduzida de agentes infecciosos. O objetivo foi avaliar a prevalência dos vírus respiratórios Influenza A (FluA), vírus sincicial respiratório (RSV) e do novo coronavírus (SARS-CoV-2) em pacientes com internação hospitalar por SRAG. Estudo transversal, com pacientes em internação hospitalar com SRAG entre novembro de 2021 e maio de 2022. Dados sociodemográficos e clínicos e amostras da nasofaringe foram coletados/as, as quais foram submetidas à extração de RNA e testadas quanto à positividade para Influenza A, RSV e SARS-CoV-2 por meio da técnica de PCR em tempo real pelo método SYBR Green. Foram incluídos 42 pacientes, sendo 59,5% do sexo feminino, 57,1% idosos, 54,8% com ensino fundamental. A maior parte dos pacientes reportou hábito tabagista prévio ou atual (54,8%), não etilista (73,8%) e 83,3% deles apresentavam alguma comorbidade, sendo hipertensão arterial sistêmica e diabetes mellitus tipo 2 as mais prevalentes. Um total de 10,5% dos pacientes testou positivo para FluA, nenhuma amostra positiva para RSV e 76,3% positivos para SARS-CoV-2. Na população estudada, SRAG com agravo hospitalar foi observado em maior proporção, em mulheres, idosos e pessoas com comorbidades, embora sem significância estatística, sendo o novo coronavírus o agente etiológico mais relacionado, o que evidencia a patogenicidade desse agente e suas consequências ainda são evidentes após quase 2 anos de período pandêmico.


Severe acute respiratory syndrome (SARS) is characterized by symptoms of high fever, cough and dyspnea, and is in most cases related to a reduced amount of infectious agents. The objective was to assess the prevalence of respiratory viruses Influenza A (FluA), respiratory syncytial virus (RSV) and the new coronavirus (SARS-CoV-2) in patients hospitalized for SARS. Cross-sectional study, with patients hospitalized with SARS between November 2021 and May 2022. Sociodemographic and clinical data and nasopharyngeal samples were collected, which were subjected to RNA extraction and tested for positivity for Influenza A, RSV and SARS-CoV-2 using the real-time PCR technique using the SYBR Green method. 42 patients were included, 59.5% female, 57.1% elderly, 54.8% with primary education. Most patients reported previous or current smoking habits (54.8%), non-drinkers (73.8) and 83.3% of them had some comorbidity, with systemic arterial hypertension and type 2 diabetes mellitus being the most prevalent. A total of 10.5% of patients tested positive for FluA, no samples positive for RSV, and 76.3% positive for SARS-CoV-2. In the studied population, SARS with hospital injury was observed more frequently in women and the elderly, with associated comorbidities, with the new coronavirus being the most related etiological agent, which shows, although not statistically significant, that the pathogenicity of this agent and its consequences are still evident after almost 2 years of period pandemic.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad
2.
BMC Infect Dis ; 24(1): 1085, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354399

RESUMEN

BACKGROUND: Treatment failure (TF) in leprosy following multidrug therapy (MDT) presents a significant challenge. The current World Health Organization (WHO) fixed-duration MDT regimen, based on lesion count, might not be adequate. Leprosy lacks clear-cut objective cure criteria, and the predictive value of post-MDT histopathological findings remains uncertain. This study aims to identify predictive factors for TF among leprosy patients who have completed the WHO-recommended MDT. METHODS: An analysis was conducted on 80 individuals from a national leprosy reference center, comprising 40 TF cases (with a mean relapse at 13.0 months) and 40 controls (with a mean of 113.1 months without disease signs). Various epidemiological and clinical-laboratory parameters were assessed post-MDT. RESULTS: In skin samples, the presence of foamy granuloma (OR = 7.36; 95%CI2.20-24.60; p = 0.0012) and histological bacillary index (hBI) ≥ 1+ (OR = 1.55; 95%CI1. 22-1.99; p = 0.0004) were significantly associated with TF, with odds ratios of 7.36 and 1.55, respectively. Individuals who experienced TF had a mean hBI of 3.02+ (SD ± 2.02), while the control group exhibited a mean hBI of 1.8+ (SD ± 1.88). An hBI ≥ 3 + showed a sensitivity of 73% and a specificity of 78% for TF detection (AUC: 0.75; p = 0.0001). Other histopathological features like epithelioid granulomas, and skin changes did not show significant associations (p > 0.05). Additionally, higher anti-phenolic glycolipid-I (anti-PGL-I) ELISA index (EI) levels were linked to a 1.4-fold increased likelihood for TF (OR = 1.4; 95%CI1.13-1.74; p = 0.0019). A mean EI of 4.48 (SD ± 2.80) was observed, with an EI ≥ 3.95 showing a sensitivity of 79% and a specificity of 59% for TF detection (AUC: 0.74; p = 0.0001). Moreover, the presence of Mycobacterium leprae (M. leprae) DNA in real-time polymerase chain reaction (qPCR) was associated with a 3.43-fold higher likelihood of TF. Multivariate regression analysis indicated that concurrent presentation of neural/perineural lymphocytic infiltrate, foamy granuloma, hBI ≥ 1+, and EI ≥ 1 markedly increased the likelihood of TF by up to 95.41%. CONCLUSION: Persistence of nerve-selective lymphocytic infiltrate, foamy granulomas, and bacilli in skin biopsies, and elevated EI post-MDT, may serve as predictive factors for identifying individuals at higher probability of TF.


Asunto(s)
Lepra , Insuficiencia del Tratamiento , Humanos , Lepra/tratamiento farmacológico , Lepra/patología , Lepra/diagnóstico , Masculino , Femenino , Adulto , Persona de Mediana Edad , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Piel/patología , Piel/microbiología , Diagnóstico Precoz , Leprostáticos/uso terapéutico , Adulto Joven , Anciano , Adolescente
3.
J Lasers Med Sci ; 15: e45, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39381787

RESUMEN

Introduction: Photobiomodulation with low-level laser treatment can enhance bone formation by stimulating the cell division of osteoblasts and increasing the amount of protein deposition, thus encouraging the formation of new bone. The aim of this study was to evaluate the effects of photobiomodulation with a low-level laser on proliferation and gene expression related to calcium signaling in human osteoblasts. Methods: Osteoblastic cell lines of the hFOB1.19 lineage, human osteoblasts, were grown and assigned into two groups, control (C; n=78 cultured wells) and photobiomodulation (L; n=78 cultured wells) with n=6 per day of the experimental period. Cells were cultured (immature at 34 ºC), and after maturation at 37 ºC, group L cells were exposed to laser irradiation with a low-level laser device (gallium and aluminum arsenide), at a wavelength of 808 nm, a power output of 200 mW, and a power density of 200 mW/cm2. The energy delivered to the cells was 37 J/cm2, with a beam area of 0.02 mm2 and an exposure time of 5 seconds. This treatment was applied daily for a period of 13 days. Following this, the number of cells was counted, and RNA was isolated, measured, and then converted into cDNA for further quantification using a comparative Ct method with real-time polymerase chain reaction. The results were then subjected to statistical analysis through a Mann-Whitney test, with a significance level of P<0.05. Results: The cell count in the L group (37.25x10±4±22.02) was statistically higher compared to the control group (22.75x10±4±7.660) with a P value of 0.0259. The values of 2-ΔΔCt for S100A6, plasma membrane calcium ATPase (PMCA), and calmodulin genes indicated hyper-expression on the thirteenth day, while the osteocalcin gene showed hypo-expression. Conclusion: The study suggests that the photobiomodulation mechanism with a low-level laser may regulate gene expression in human osteoblasts in a dose-dependent and cumulative manner.

4.
Lab Anim ; : 236772241257132, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39257337

RESUMEN

This study aimed to investigate the presence of murine astrovirus (MuAstV) in Brazil. Fecal samples from mice belonging to four Brazilian animal facilities were collected and tested for MuAstV using real-time polymerase chain reaction. Of the 162 samples tested, 38 (23.5%) were positive for MuAstV, 33 (91.7%) of which came from specific-pathogen free colonies. Although most of the samples were obtained from asymptomatic animals, three mice presented diarrheal symptoms, and MuAstV was the only agent detected by molecular assay. Phylogenetic analysis revealed similarities between the MuAstV strains from this study and prototypes from the USA. MuAstV's high prevalence, environmental stability, genetic diversity and potential for persistent infections must be considered when evaluating health monitoring programs for laboratory rodents.

5.
Antibiotics (Basel) ; 13(9)2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39335051

RESUMEN

Advanced diagnostic technologies have made accurate and precise diagnosis of pathogens easy. Herein, we present a new diagnostic method, droplet digital PCR (ddPCR), to detect and quantify Acinetobacter baumannii in mini bronchoalveolar lavage (mini-BAL) samples. A. baumannii causes ventilator-associated pneumonia (VAP), a severe healthcare infection affecting patients' lungs. VAP carries a high risk of morbidity and mortality, making its timely diagnosis crucial for prompt and effective management. Methodology. The assay performance was evaluated by comparing colonization data, quantitative culture results, and different generations of PCR (traditional PCR and Real-Time PCR-qPCR Taqman® and SYBR® Green). The ddPCR and qPCR Taqman® prove to be more sensitive than other molecular techniques. Reasonable analytical specificity was obtained with ddPCR, qPCR TaqMan®, and conventional PCR. However, qPCR SYBR® Green technology presented a low specificity, making the results questionable in clinical samples. DdPCR detected/quantified A. baumanni in more clinical samples than other methods (38.64% of the total samples). This emerging ddPCR technology offers promising advantages such as detection by more patients and direct quantification of pathogens without calibration curves.

6.
Int J Mol Sci ; 25(18)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39337258

RESUMEN

The transmembrane nitrate reductase (Nar) is the first enzyme in the dissimilatory alternate anaerobic nitrate respiratory chain in denitrifying bacteria. To date, there has been no real-time method to determine its specific activity embedded in its native membrane; here, we describe such a new method, which is useful with the inside-out membranes of Paracoccus denitrificans and other denitrifying bacteria. This new method takes advantage of the native coupling of the endogenous NADH dehydrogenase or Complex I with the reduction of nitrate by Nar through the quinone pool of the inner membranes of P. denitrificans. This is achieved under previously reached anaerobic conditions. Inner controls confirming the specific Nar activity determined by this new method were made by the total inhibition of the Nar enzyme by sodium azide and cyanide, well-known Nar inhibitors. The estimation of the Michaelis-Menten affinity of Nar for NO3- using this so-called Nar-JJ assay gave a Km of 70.4 µM, similar to previously determined values. This new Nar-JJ assay is a suitable, low-cost, and reproducible method to determine in real-time the endogenous Nar activity not only in P. denitrificans, but in other denitrifying bacteria such as Brucella canis, and potentially in other entero-pathogenic bacteria.


Asunto(s)
Desnitrificación , Nitrato-Reductasa , Paracoccus denitrificans , Paracoccus denitrificans/enzimología , Paracoccus denitrificans/metabolismo , Nitrato-Reductasa/metabolismo , Nitratos/metabolismo , Cinética
7.
Artículo en Inglés | MEDLINE | ID: mdl-39160330

RESUMEN

PURPOSE: To introduce a computational tool for peri-interventional intracranial aneurysm treatment guidance that maps preoperative planning information from simulation onto real-time X-Ray imaging. METHODS: Preoperatively, multiple flow diverter (FD) devices are simulated based on the 3D mesh of the vessel to treat, to choose the optimal size and location. In the peri-operative stage, this 3D information is aligned and mapped to the continuous 2D-X-Ray scan feed from the operating room. The current flow diverter position in the 3D model is estimated by automatically detecting the distal FD marker locations and mapping them to the treated vessel. This allows to visually assess the possible outcome of releasing the device at the current position, and compare it with the one chosen pre-operatively. RESULTS: The full pipeline was validated using retrospectively collected biplane images from four different patients (5 3D-DSA datasets in total). The distal FD marker detector obtained an average F1-score of 0.67 ( ± 0.224 ) in 412 2D-X-Ray scans. After aligning 3D-DSA + 2D-X-Ray datasets, the average difference between simulated and deployed positions was 0.832 mm ( ± 0.521 mm). Finally, we qualitatively show that the proposed approach is able to display the current location of the FD compared to their pre-operatively planned position. CONCLUSIONS: The proposed method allows to support the FD deployment procedure by merging and presenting preoperative simulation information to the interventionists, aiding them to make more accurate and less risky decisions.

8.
Front Cell Infect Microbiol ; 14: 1412007, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39211796

RESUMEN

The collective involvement of virulence markers of Escherichia coli as an emerging pathogen associated with periodontitis remains unexplained. This study aimed to implement an in vitro model of infection using a human epithelial cell line to determine the virulome expression related to the antibiotic and disinfectant resistance genotype and pulse field gel electrophoresis (PFGE) type in E. coli strains isolated from patients with periodontal diseases. We studied 100 strains of E. coli isolated from patients with gingivitis (n = 12), moderate periodontitis (n = 59), and chronic periodontitis (n = 29). The identification of E. coli and antibiotic and disinfectant resistance genes was performed through PCR. To promote the expression of virulence genes in the strains, an in vitro infection model was used in the human epithelial cell line A549. RNA was extracted using the QIAcube robotic equipment and reverse transcription to cDNA was performed using the QuantiTect reverse transcription kit (Qiagen). The determination of virulence gene expression was performed through real-time PCR. Overall, the most frequently expressed adhesion genes among the isolated strains of gingivitis, moderate periodontitis, and chronic periodontitis were fimH (48%), iha (37%), and papA (18%); those for toxins were usp (33%); those for iron acquisition were feoB (84%), fyuA (62%), irp-2 (61%), and iroN (35%); those for protectins were traT (50%), KpsMT (35%), and ompT (28%); and those for pathogenicity islands were malX (45%). The most common antibiotic and disinfectant resistance genes among gingivitis, moderate periodontitis, and chronic periodontitis strains were sul-2 (43%), blaSHV (47%), blaTEM (45%), tet(A) (41%), dfrA1 (32%), marR-marO (57%), and qacEA1 (79%). The findings revealed the existence of a wide distribution of virulome expression profiles related to the antibiotic and disinfectant resistance genotype and PFGE type in periodontal strains of E. coli. These findings may contribute toward improving the prevention and treatment measures for periodontal diseases associated with E. coli.


Asunto(s)
Antibacterianos , Desinfectantes , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli , Escherichia coli , Factores de Virulencia , Humanos , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Factores de Virulencia/genética , Antibacterianos/farmacología , Infecciones por Escherichia coli/microbiología , Farmacorresistencia Bacteriana/genética , Desinfectantes/farmacología , Periodontitis/microbiología , Virulencia/genética , Células A549 , Células Epiteliales/microbiología , Genotipo , Adulto , Femenino , Masculino , Persona de Mediana Edad , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Electroforesis en Gel de Campo Pulsado
9.
Braz J Microbiol ; 55(3): 2547-2556, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38977544

RESUMEN

Campylobacter is gram-negative bacteria considered the predominant genera isolated from poultry samples and associated with gastroenteritis. Due to the problems in conventional cultural methods of time-consuming and technically demanding requirements, a rapid and feasible method for their identification and discrimination of the closely related spp. Including Campylobacter coli, Campylobacter fetus, and Campylobacter jejuni is needed. This study analyzes the chicken and sheep meats samples (n = 125) using culture and pre-enrichment-based Quadraplex real-time PCR by targeting OrfA, CstA, HipO, and 16 S rRNA genes of C. coli, C. fetus, C. jejuni and Campylobacter spp. Respectively. The analysis of 125 chicken and sheep meat samples by culture and real-time PCR showed high concordance between the results of the two methods. The present study show high prevalence of Campylobacter species (35% and 32% from chicken and meat respectively) of which C. jejuni were the most abundant. Reaction efficiencies were between 90 and 110%, and detect as low as 8.9 fg in C. jejuni. The need for quick detection and discrimination methods in sheep and chicken meat can be met using the described Quadraplex real-time PCR methodology.


Asunto(s)
Campylobacter coli , Campylobacter jejuni , Pollos , Carne , Reacción en Cadena en Tiempo Real de la Polimerasa , Animales , Pollos/microbiología , Ovinos/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Campylobacter coli/genética , Campylobacter coli/aislamiento & purificación , Campylobacter coli/clasificación , Campylobacter jejuni/genética , Campylobacter jejuni/aislamiento & purificación , Campylobacter jejuni/clasificación , Carne/microbiología , Campylobacter fetus/genética , Campylobacter fetus/aislamiento & purificación , Campylobacter fetus/clasificación , Campylobacter/genética , Campylobacter/aislamiento & purificación , Campylobacter/clasificación , Microbiología de Alimentos , ADN Bacteriano/genética
10.
Vet Parasitol Reg Stud Reports ; 53: 101068, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39025541

RESUMEN

Leishmaniases are a group of neglected diseases of significant public health concern, with Brazil being the primary focus of this disease in the Americas. The municipality of Sobral, in the state of Ceará, is a historical focus of visceral leishmaniasis in both humans and dogs, but data on Leishmania spp. infections in cats are limited. Between April 2021 and February 2022, 205 cats from a referral hospital population were sampled and tested for Leishmania spp. by real-time PCR. Eight cats (3.9%; 95% CI: 1.7-7.5%) tested positive. Among these, three (37.5%) displayed clinical signs compatible with feline leishmaniosis. Non-domiciled cats showed significantly higher positivity compared to domiciled ones (Fisher's exact test, P = 0.0124). Considering their potential role as reservoirs of L. infantum, it is crucial to conduct further studies to understand the Leishmania spp. circulating among cats in Sobral and to implement measures for reducing their exposure to phlebotomine sand fly vectors in this important focus of leishmaniases.


Asunto(s)
Enfermedades de los Gatos , Leishmaniasis , Animales , Gatos , Brasil/epidemiología , Enfermedades de los Gatos/epidemiología , Enfermedades de los Gatos/parasitología , Prevalencia , Femenino , Masculino , Leishmaniasis/veterinaria , Leishmaniasis/epidemiología , Leishmaniasis/parasitología , Leishmania/aislamiento & purificación , Leishmaniasis Visceral/veterinaria , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/parasitología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Hospitales Veterinarios , Leishmania infantum/aislamiento & purificación
11.
Res Vet Sci ; 177: 105363, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39053093

RESUMEN

Cutaneous squamous cell carcinoma (cSCC) is a neoplasm type often diagnosed in dogs. However, studies focused on further investigating its molecular biology, mainly biomarkers to help implementing new therapies, remain scare in the literature. Thus, immunostaining and the gene expression of epidermal growth factor receptors (HER1 and HER2) in canine cSCC presenting different cell differentiation degrees were herein assessed. Thirty-two (32) canine cSCC were selected, classified based on to their cell differentiation degree and subjected to immunohistochemical study to assess HER1 and HER2 immunostaining intensity and distribution. In addition, HER1 and HER2 gene expression was investigated through real-time PCR. Membranous and cytoplasmic immunostaining were observed in both markers. HER2 prevailed in poorly differentiated cSCC; there was positive protein expression correlation between both markers. Mean HER1 gene expression was higher in moderately differentiated, whereas mean HER2 gene expression was higher in poorly differentiated cSCC. Moreover, there was gene expression correlation between markers, regardless of cell differentiation degree. Thus, HER2 protein immunostaining and gene expression were higher in poorly differentiated canine cSCC and it enabled understanding that increase observed in this epidermal growth factor receptor is proportional to this neoplasm's cell differentiation degree in canine species. Results in the current study helped better understanding canine cSCC's molecular biology; however, it is relevant studying other markers aiming to investigate signaling pathways.


Asunto(s)
Carcinoma de Células Escamosas , Enfermedades de los Perros , Receptores ErbB , Inmunohistoquímica , Receptor ErbB-2 , Neoplasias Cutáneas , Animales , Perros , Enfermedades de los Perros/genética , Enfermedades de los Perros/metabolismo , Carcinoma de Células Escamosas/veterinaria , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Cutáneas/veterinaria , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Inmunohistoquímica/veterinaria , Femenino , Regulación Neoplásica de la Expresión Génica , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
12.
Braz J Microbiol ; 55(3): 2715-2726, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38926315

RESUMEN

Pseudomonas aeruginosa is one of the most important nosocomial pathogens that possess the ability to produce multiple antibiotic resistance and virulence factors. Elastase B (LasB) is the major factor implicated in tissue invasion and damage during P. aeruginosa infections, whose synthesis is regulated by the quorum sensing (QS) system. Anti-virulence approach is now considered as potential therapeutic alternative and/or adjuvant to current antibiotics' failure. The aim of this study is primarily to find out the impact of the efflux pump inhibitor (EPI) phenylalanine arginyl ß-naphthylamide (PAßN) on the production of elastase B and the gene expression of lasI quorum sensing and lasB virulence factor in clinical isolates of P. aeruginosa. Five P. aeruginosa isolates recovered from patients with respiratory tract infections were examined in this study. Antimicrobial susceptibility of isolates was performed by the disk agar diffusion method. Effect of the PAßN on imipenem susceptibility, bacterial viability, and elastase production was evaluated. The expression of lasB and lasI genes was measured by quantitative real-time PCR in the presence of PAßN. All isolates were identified as multidrug-resistant (MDR) and showed resistance to carbapenem (MIC = 64-256 µg/mL). Susceptibility of isolates to imipenem was highly increased in the presence of efflux inhibitor. PAßN significantly reduced elastase activity in three isolates tested without affecting bacterial growth. In addition, the relative expression of both lasB and lasI genes was diminished in all isolates in the presence of inhibitor. Efflux inhibition by using the EPI PAßN could be a potential target for controlling the P. aeruginosa virulence and pathogenesis. Furthermore, impairment of drug efflux by PAßN indicates its capability to be used as antimicrobial adjuvant that can decrease the resistance and lower the effective doses of current drugs.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Dipéptidos , Imipenem , Pruebas de Sensibilidad Microbiana , Elastasa Pancreática , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Percepción de Quorum , Factores de Virulencia , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/aislamiento & purificación , Percepción de Quorum/efectos de los fármacos , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Elastasa Pancreática/genética , Elastasa Pancreática/metabolismo , Antibacterianos/farmacología , Humanos , Infecciones por Pseudomonas/microbiología , Dipéptidos/farmacología , Imipenem/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Farmacorresistencia Bacteriana , Metaloendopeptidasas
13.
Fitoterapia ; 177: 106101, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38945495

RESUMEN

Helicobacter pylori is a bacterium that is present in the stomach of about 50% of the global population and is associated with several gastric disorders, including cancer. Natural products with antimicrobial activity have been tested against H. pylori, among them Trichilia catigua (catuaba), which is widely distributed in Brazil. This study aimed to evaluate extracts of T. catigua bark against H. pylori via determination of the minimum inhibitory and bactericidal concentrations (MIC and MBC); evaluation of virulence factors by real-time PCR, synergism with standard antimicrobials and morphology by scanning electron microscopy and simulations of the mechanism of action by molecular docking. The ethyl acetate fraction provided the best results, with an MIC50 of 250 µg/mL and a 42.34% reduction in urease activity, along with reduced expression of the CagA and VacA genes, which encode for the main virulence factors. This fraction presented synergistic activity with clarithromycin, reducing the MIC of the drug by four-fold. Docking simulations suggested that the extracts inhibit fatty acid synthesis by the FAS-II system, causing damage to the cell membrane. Therefore, T. catigua extracts have potential as an adjuvant to treatment and are promising for the development of new anti-H. pylori drugs.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Helicobacter pylori , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Corteza de la Planta , Extractos Vegetales , Helicobacter pylori/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Corteza de la Planta/química , Brasil , Factores de Virulencia , Meliaceae/química , Claritromicina/farmacología , Ureasa , Sinergismo Farmacológico , Antígenos Bacterianos
14.
Lupus ; 33(8): 797-803, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38709545

RESUMEN

Cytomegalovirus (CMV) infection and disease is a condition usually described in immunocompromised patients, but among them, those with connective tissue diseases are poorly represented. Here we present the clinical, laboratory characteristics, management and outcomes of systemic lupus erythematosus (SLE) patients who presented with a CMV infection/disease to a high complexity hospital in southwestern Colombia between 2011 and 2020. 16 SLE patients were found to have a CMV infection. SLE was predominantly characterized by renal involvement (10 patients; 62.50%), and 14 patients (87.5%) were receiving steroids previous to the CMV infection. The entire sample required hospital admission, mainly related to acute kidney injury, and nine patients were admitted to the intensive care unit (ICU). Gastrointestinal organ damage was the most common CMV disease manifestation. All patients received ganciclovir, five of them (31.25%) suffered from septic shock, and seven (43.75%) died. Age ≥38 years and the presence of septic shock at admission were correlated to the mortality outcome. To our knowledge, this is the first publication evaluating SLE patients with CMV infection/disease in a Colombian population.


Asunto(s)
Infecciones por Citomegalovirus , Lupus Eritematoso Sistémico , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/epidemiología , Colombia/epidemiología , Femenino , Adulto , Masculino , Persona de Mediana Edad , Antivirales/uso terapéutico , Adulto Joven , Ganciclovir/uso terapéutico , Huésped Inmunocomprometido , Choque Séptico/etiología , Estudios Retrospectivos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/epidemiología , Hospitalización/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos
15.
J Virol Methods ; 327: 114948, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718900

RESUMEN

Rabies, a fatal zoonotic viral disease affecting mammals, including humans, remains a significant global health concern, particularly in low-income countries. The disease, primarily transmitted through infected animal saliva, prompts urgent diagnosis for timely post-exposure prophylaxis (PEP). The gold standard diagnostic test, direct fluorescent antibody test (dFAT), while sensitive, suffers from limitations such as subjective interpretation and high costs. As a confirmatory technique, the LN34 Pan-Lyssavirus RT-qPCR assay has emerged as a promising tool for universal Lyssavirus detection. This study evaluated its performance using 130 rabies virus isolates representing eleven Brazilian variants and 303 clinical samples from surveillance operations. The LN34 assay demonstrated 100% sensitivity and 98% specificity compared to dFAT. Additionally, it detected all samples, including those missed by dFAT, indicating superior sensitivity. The assay's specificity was confirmed through Sanger nucleotide sequencing, with only a minimal false-positive rate. Comparative analysis revealed higher accuracy and concordance with dFAT than traditional rabies tissue culture infection tests (RTCIT). False-negative RTCIT results were attributed to low viral load or suboptimal sampling. These findings underscore the LN34 assay's utility as a confirmatory technique, enhancing rabies surveillance and control in Brazil. Its widespread adoption could significantly improve diagnostic sensitivity, crucial for effective PEP and public health interventions.


Asunto(s)
Virus de la Rabia , Rabia , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Rabia/diagnóstico , Rabia/veterinaria , Rabia/virología , Brasil , Virus de la Rabia/genética , Virus de la Rabia/aislamiento & purificación , Virus de la Rabia/clasificación , Humanos , Animales , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Lyssavirus/genética , Lyssavirus/aislamiento & purificación , Lyssavirus/clasificación , ARN Viral/genética , Carga Viral
16.
Biomimetics (Basel) ; 9(5)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38786474

RESUMEN

In this paper, we address the challenge of ensuring stability in bipedal walking robots and exoskeletons. We explore the feasibility of real-time implementation for the Predicted Step Viability algorithm (PSV), a complex multi-step optimization criterion for planning future steps in bipedal gait. To overcome the high computational cost of the PSV algorithm, we performed an analysis using 11 classification algorithms and a stacking strategy to predict if a step will be stable or not. We generated three datasets of increasing complexity through PSV simulations to evaluate the classification performance. Among the classifiers, k Nearest Neighbors, Support Vector Machine with Radial Basis Function Kernel, Decision Tree, and Random Forest exhibited superior performance. Multi-Layer Perceptron also consistently performed well, while linear-based algorithms showed lower performance. Importantly, the use of stacking did not significantly improve performance. Our results suggest that the feature vector applied with this approach is applicable across various robotic models and datasets, provided that training data is balanced and sufficient points are used. Notably, by leveraging classifiers, we achieved rapid computation of results in less than 1 ms, with minimal computational cost.

17.
BMC Gastroenterol ; 24(1): 166, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755577

RESUMEN

INTRODUCTION: The diagnosis of intestinal tuberculosis is challenging even nowadays. This study aims to report the positivity rates of new diagnostic methods such as immunohistochemistry and Real-Time Polymerase Chain Reaction in patients with intestinal tuberculosis, as well as describe the pathological and endoscopic features of intestinal tuberculosis in our population. METHODS: This was a retrospective observational study conducted in patients diagnosed with intestinal tuberculosis, between 2010 to 2023 from the Hospital Nacional Daniel Alcides Carrion and a Private Pathology Center, both located in Peru. Clinical data was obtained, histologic features were independently re-evaluated by three pathologists; and immunohistochemistry and real-time Polymerase Chain Reaction evaluation were performed. The 33 patients with intestinal tuberculosis who fulfilled the inclusion criteria were recruited. RESULTS: Immunohistochemistry was positive in 90.9% of cases, while real-time Polymerase Chain Reaction was positive in 38.7%. The ileocecal region was the most affected area (33.3%), and the most frequent endoscopic appearance was an ulcer (63.6%). Most of the granulomas were composed solely of epithelioid histiocytes (75.8%). Crypt architectural disarray was the second most frequent histologic finding (78.8%) after granulomas, but most of them were mild. CONCLUSION: Since immunohistochemistry does not require an intact cell wall, it demonstrates higher sensitivity compared to Ziehl-Neelsen staining. Therefore, it could be helpful for the diagnosis of paucibacillary tuberculosis.


Asunto(s)
Inmunohistoquímica , Reacción en Cadena en Tiempo Real de la Polimerasa , Tuberculosis Gastrointestinal , Humanos , Tuberculosis Gastrointestinal/diagnóstico , Tuberculosis Gastrointestinal/microbiología , Perú , Masculino , Femenino , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Granuloma/diagnóstico , Granuloma/microbiología , Granuloma/patología , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Adolescente , Sensibilidad y Especificidad
18.
Methods Mol Biol ; 2787: 209-223, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38656492

RESUMEN

Coffea spp. is the source of one of the most widely consumed beverages in the world. However, the cultivation of this crop is threatened by Hemileia vastatrix Berk & Broome, a fungal disease, which reduces the productivity and can cause significant economic losses. In this protocol, coffee leaf segment derived from a chemical mutagenesis process are inoculated with uredospores of the pathogen. Subsequently, the gene expression changes are analyzed over the time (0, 5, 24, 48, and 120 h) using quantitative real-time polymerase chain reaction (RT-qPCR). The procedures and example data are presented for expression analysis in the CaWRKY1 gene. This procedure can be applied for quantitative analysis of other genes of interest to coffee breeders and scientists for elucidating the molecular mechanisms involved in the interaction between the plant and pathogen, potentially leading to the development of more efficient approaches for managing this disease.


Asunto(s)
Basidiomycota , Coffea , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Coffea/microbiología , Coffea/genética , Basidiomycota/genética , Basidiomycota/patogenicidad , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Perfilación de la Expresión Génica/métodos , Mutación , Hojas de la Planta/microbiología , Hojas de la Planta/genética , Interacciones Huésped-Patógeno/genética
19.
Braz J Microbiol ; 55(2): 1783-1791, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38687417

RESUMEN

The aim of the present study was to compare the performance of a nested polymerase chain reaction (nPCR) and a real-time PCR based on the amplification of the HlyA gene from Listeria monocytogenes using a plasmid DNA standard. Nested PCR was developed with an internal amplification control (IAC). Both techniques were validated in soft cheese samples by comparing their results with the results of the microbiological reference method ISO 11290-1:2017. Cheese samples artificially contaminated with 3.5 to 3,500 UFC/25 g were processed by ISO 11290-1:2017 and, at several times of culture, DNA samples were extracted. All cheeses contaminated with L. monocytogenes were positive for the microbiological method 96 h post contamination and for nPCR and real-time PCR 48 h post contamination. At this time, the HlyA gene was amplified in all contaminated samples. Both molecular techniques showed the same sensitivity, 30 copies/reaction or 3.5 UFC/25 g, when plasmid DNA standard or artificially contaminated cheese samples were used. Finally, eighty soft cheese samples obtained from local retail stores and tested by three methods were negative, indicating a 100% concordance in results. The development of an nPCR with IAC reinforces the reliability of the negative results without increasing the costs of the reaction. Besides, nPCR showed less sensitivity to the presence of inhibitory substances in the reaction. The use of one of these molecular techniques could be easily coupled to the microbiological method, serving as a screening method in the food industry for hygiene monitoring and early identification of contaminated foods.


Asunto(s)
Queso , Microbiología de Alimentos , Listeria monocytogenes , Reacción en Cadena de la Polimerasa , Reacción en Cadena en Tiempo Real de la Polimerasa , Queso/microbiología , Listeria monocytogenes/genética , Listeria monocytogenes/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/métodos , Microbiología de Alimentos/métodos , Proteínas Hemolisinas/genética , Toxinas Bacterianas/genética , ADN Bacteriano/genética , Proteínas de Choque Térmico
20.
Ecotoxicology ; 33(6): 1-12, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38602608

RESUMEN

The annual killifish Austrolebias charrua is an endangered species, endemic to the southern region of South America, which inhabits temporary ponds that emerges in the rainy season. The main anthropogenic threat driving the extinction of A. charrua stems from extensive agriculture, primarily due to the widrespread use of glyphosate-based herbicides near their habitats. Annual killifishes have been used as models for ecotoxicological studies but, up to now, there are no studies about reference genes in any Austrolebias species. This represents an obstacle to the use of qPCR-based technologies, the standard method for gene expression quantification. The present study aimed to select and validate potential reference genes for qPCR normalization in the annual killifish Austrolebias charrua considering different tissues, gender and environmental conditions. The candidate reference genes 18 s, actb, gapdh, ef1a, shox, eif3g, and the control gene atp1a1 were evaluated in male and female individuals in three different tissues (brain, liver, and gills) under two experimental conditions (control and acute exposition to Roundup Transorb®). The collected tissues were submitted to RNA extraction, followed by cDNA synthesis, cloning, sequencing, and qPCR. Overall, 18 s was the most stable reference gene, and 18 s and ef1a were the most stable combination. Otherwise, considering all variables, gapdh and shox were the least stable candidate genes. Foremost, suitable reference genes were validated in A. charrua, facilitating accurate mRNA quantification in this species, which might be useful for developing molecular tools of ecotoxicological assessment based on gene expression analysis for environmental monitoring of annual killifish.


Asunto(s)
Especies en Peligro de Extinción , Reacción en Cadena en Tiempo Real de la Polimerasa , Animales , Masculino , Femenino , Contaminantes Químicos del Agua/toxicidad , Fundulidae/genética , Monitoreo del Ambiente/métodos , Glifosato , Factores Sexuales , Herbicidas/toxicidad , Peces Killi
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA