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1.
Hum Genomics ; 18(1): 16, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38326874

RESUMO

BACKGROUND: Diabetes is a spectrum of metabolic diseases affecting millions of people worldwide. The loss of pancreatic ß-cell mass by either autoimmune destruction or apoptosis, in type 1-diabetes (T1D) and type 2-diabetes (T2D), respectively, represents a pathophysiological process leading to insulin deficiency. Therefore, therapeutic strategies focusing on restoring ß-cell mass and ß-cell insulin secretory capacity may impact disease management. This study took advantage of powerful integrative bioinformatic tools to scrutinize publicly available diabetes-associated gene expression data to unveil novel potential molecular targets associated with ß-cell dysfunction. METHODS: A comprehensive literature search for human studies on gene expression alterations in the pancreas associated with T1D and T2D was performed. A total of 6 studies were selected for data extraction and for bioinformatic analysis. Pathway enrichment analyses of differentially expressed genes (DEGs) were conducted, together with protein-protein interaction networks and the identification of potential transcription factors (TFs). For noncoding differentially expressed RNAs, microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), which exert regulatory activities associated with diabetes, identifying target genes and pathways regulated by these RNAs is fundamental for establishing a robust regulatory network. RESULTS: Comparisons of DEGs among the 6 studies showed 59 genes in common among 4 or more studies. Besides alterations in mRNA, it was possible to identify differentially expressed miRNA and lncRNA. Among the top transcription factors (TFs), HIPK2, KLF5, STAT1 and STAT3 emerged as potential regulators of the altered gene expression. Integrated analysis of protein-coding genes, miRNAs, and lncRNAs pointed out several pathways involved in metabolism, cell signaling, the immune system, cell adhesion, and interactions. Interestingly, the GABAergic synapse pathway emerged as the only common pathway to all datasets. CONCLUSIONS: This study demonstrated the power of bioinformatics tools in scrutinizing publicly available gene expression data, thereby revealing potential therapeutic targets like the GABAergic synapse pathway, which holds promise in modulating α-cells transdifferentiation into ß-cells.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Insulinas , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Redes Reguladoras de Genes/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Diabetes Mellitus Tipo 2/genética , Fatores de Transcrição/genética , Insulinas/genética , Biologia Computacional , Proteínas de Transporte/genética , Proteínas Serina-Treonina Quinases/genética
2.
Phys Rev Lett ; 126(11): 117205, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33798341

RESUMO

We report experimental coupling of chiral magnetism and superconductivity in [IrFeCoPt]/Nb heterostructures. The stray field of skyrmions with radius ≈50 nm is sufficient to nucleate antivortices in a 25 nm Nb film, with unique signatures in the magnetization, critical current, and flux dynamics, corroborated via simulations. We also detect a thermally tunable Rashba-Edelstein exchange coupling in the isolated skyrmion phase. This realization of a strongly interacting skyrmion-(anti)vortex system opens a path toward controllable topological hybrid materials, unattainable to date.

3.
J Appl Microbiol ; 131(4): 2049-2060, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33694241

RESUMO

AIMS: The aim of this study was to evaluate the formation of biofilm by Candida spp. isolated from the bloodstream, using traditional spectrophotometric methodologies. In addition, the goal was to compare the results with those obtained through MALDI-TOF/MS, as well as to verify its use as a potential tool for the detection of biofilm-forming strains. METHODS AND RESULTS: Hundred and thirteen isolates of Candida spp. were studied: 41 were Candida albicans, 27 C. tropicalis, 18 C. glabrata, 17 C. parapsilosis and 10 C. krusei. Metabolic activity was determined through the tetrazolium salt (XTT) reduction assay and biomass by staining with Crystal Violet. All isolates were able to form biofilm, 94% of which were strong producers, with high biomass quantification (95%; 107/113) and high metabolic activity (99%; 112/113). Mass spectra of the biofilm-producing isolates showed differences in the intensity of mass peaks when compared with the spectra of the nonproducing strains. CONCLUSIONS: It was demonstrated that MALDI-TOF/MS was able to detect specific biofilm proteins, as the mass spectra of the isolates presented differences when compared with nonproducing strains. SIGNIFICANCE AND IMPACT OF THE STUDY: MALDI-TOF/MS can become a valuable tool for biofilm detection at the moment of the identification of the microorganism, thus contributing greatly to the management of patients with Candidemia.


Assuntos
Candida , Candidemia , Biofilmes , Candida albicans , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
Kathmandu Univ Med J (KUMJ) ; 19(73): 96-101, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34812166

RESUMO

Background Various methods had been used for personal identification. Scientific basis of identification was initiated and progressed after 19th century which may be attributed to various scientists. With the invention of X-ray the field of identification further progressed. Modern radiological diagnostic equipments have greatly assisted in the field of forensic. Frontal sinuses are paired lobulated air cavities located posterior to superciliary arches in the frontal bone. Computed Tomography is best used to study frontal sinuses. Objective To evaluate bilateral Frontal sinus for sexual dimorphism using Computed Tomography. Method Anterior posterior length, transverse width and height of the bilateral Frontal sinus were directly measured on CT DICOM image, using Electronic Caliper in DICOM viewer software. A total 100 CT scans, 50 of each sex were collected was analysed using SPSS-20 in present study. Result The mean age distribution for male is 34.74±8.66, and for females 35.34±8.88. The mean of all the measurements take was larger in males in comparison to females with p < 0.00. The paired t test showed left side is larger than right. The discriminant function showed high significance for each measurement and also when all the measurements were combined. Conclusion Though the study being unique for Nepalese population, caution should be taken when frontal sinus is used as the only parameter. However in combination with other morphometric data is advised.


Assuntos
Seio Frontal , Análise Discriminante , Feminino , Seio Frontal/diagnóstico por imagem , Humanos , Masculino , Software , Tomografia Computadorizada por Raios X
5.
Brain Behav Immun ; 80: 500-511, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31022457

RESUMO

Overweight and obesity are a worldwide pandemic affecting billions of people. These conditions have been associated with a chronic low-grade inflammatory state that is recognized as a risk factor for a range of somatic diseases as well as neurodevelopmental disorders, anxiety disorders, trauma- and stressor-related disorders, and affective disorders. We previously reported that the ingestion of a high-fat diet (HFD; 45% fat kcal/g) for nine weeks was capable of inducing obesity in rats in association with increased reactivity to stress and increased anxiety-related defensive behavior. In this study, we conducted a nine-week diet protocol to induce obesity in rats, followed by investigation of anxiety-related defensive behavioral responses using the elevated T-maze (ETM), numbers of FOS-immunoreactive cells after exposure of rats to the avoidance or escape task of the ETM, and neuroinflammatory cytokine expression in hypothalamic and amygdaloid nuclei. In addition, we investigated stress-induced cutaneous thermoregulatory responses during exposure to an open-field (OF). Here we demonstrated that nine weeks of HFD intake induced obesity, in association with increased abdominal fat pad weight, increased anxiety-related defensive behavioral responses, and increased proinflammatory cytokines in hypothalamic and amygdaloid nuclei. In addition, HFD exposure altered avoidance- or escape task-induced FOS-immunoreactivity within brain structures involved in control of neuroendocrine, autonomic, and behavioral responses to aversive stimuli, including the basolateral amygdala (BLA) and dorsomedial (DMH), paraventricular (PVN) and ventromedial (VMH) hypothalamic nuclei. Furthermore, rats exposed to HFD, relative to control diet-fed rats, responded with increased tail skin temperature at baseline and throughout exposure to an open-field apparatus. These data are consistent with the hypothesis that HFD induces neuroinflammation, alters excitability of brain nuclei controlling neuroendocrine, autonomic, and behavioral responses to stressful stimuli, and enhances stress reactivity and anxiety-like defensive behavioral responses.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Dieta Hiperlipídica/efeitos adversos , Neuroimunomodulação/fisiologia , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/metabolismo , Transtornos de Ansiedade/metabolismo , Corticosterona , Hipotálamo/metabolismo , Masculino , Obesidade , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Aumento de Peso
6.
J Appl Microbiol ; 127(5): 1373-1380, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31339616

RESUMO

AIMS: Violacein (VIO), a bacterial pigment produced by Chromobacterium violaceum, was examined to evaluate the antichagasic activity and its action mechanism against Trypanosoma cruzi Y strain. METHODS AND RESULTS: Violacein was tested against the epimastigote, trypomastigote and amastigote forms of T. cruzi Y strain (benznidazole-resistant strain). VIO inhibited all T. cruzi developmental forms, including amastigotes, which is implicated in the burden of infection in the chronic phase of Chagas disease (CD). VIO induced cell death in T. cruzi through apoptosis, as determined by flow cytometry analyses with specific molecular probes and morphological alterations, such as involvement of reactive oxygen species and changes in mitochondrial membrane potential and cell shrinkage. CONCLUSION: The results suggest antichagasic activity of VIO against T. cruzi Y strain with apoptotic involvement. SIGNIFICANCE AND IMPACT OF THE STUDY: The treatment of CD has limited efficacy and side effects that restrict patient tolerability and compliance. The VIO molecule could be used as a model for therapeutic alternatives for this disease.


Assuntos
Chromobacterium/química , Indóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Resistência a Medicamentos , Humanos , Indóis/isolamento & purificação , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nitroimidazóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Trypanosoma cruzi/crescimento & desenvolvimento
7.
Med Oral Patol Oral Cir Bucal ; 24(3): e305-e313, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31011141

RESUMO

BACKGROUND: To evaluate the frequency of maxillary dentures-related lesions and the possible associated risk factors. MATERIAL AND METHODS: Ninety-seven participants were selected, and a complete anamnesis, physical examination and tests of occlusion vertical dimension (OVD), retention and stability of the denture, biofilm quantification, cytopathology, sialometry, pH analysis and buffer capacity of the saliva were performed. Statistical analyses were performed with the Pearson's chi-square, Mann-Whitney tests, and Pearson's coefficient (p<0.05). RESULTS: In 78% of the participants at least one denture-related lesion was found. Denture-associated stomatitis (63%), inflammatory fibrous hyperplasia (19%) and traumatic ulceration (11%) were the 3 most frequent lesions. The habit of night use of the denture was considered an independent risk factor for the development of oral lesions [OR=3.0 (95% CI 1.09-8.56); p<0.05]. Furthermore, the longest period of use of the same denture and biofilm also had statistically significant relation to oral lesions. The biofilm seems to be more related to the prevalence of oral lesions according to the multiple logistic regression [OR=1.3 (95% CI: 1.01-1.83) p<0.05]. The lack of a dentures' cleaning solution and detrition of the prothesis were independent risk factors for denture-associated stomatitis. Male gender, loss of OVD and bad buffer capacity were risk factors for angular cheilitis. Fractures of the base and repair of broken dentures were risk factors for traumatic ulcers. CONCLUSIONS: These results show a high frequency of denture-related lesions. Besides, participants hygiene habits and poor quality of the dentures were the main factors for the development of these lesions.


Assuntos
Dentaduras , Estomatite sob Prótese , Estudos Transversais , Humanos , Masculino , Maxila , Fatores de Risco
8.
J Helminthol ; 92(2): 210-215, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28397630

RESUMO

The aims of the present study were to identify and describe the occurrence of nematode parasites in the gonads of bluefish Pomatomus saltatrix from off the coast of the state of Rio de Janeiro, Brazil. Only females were found to be parasitized by the nematodes, which were identified as P. saltatrix using morphological, morphometric and molecular data. Infection of female bluefish by this nematode had the following values: prevalence, 48.7%; mean intensity, 2.6; mean abundance, 1.3; and range of infection, 1-10 specimens. Histopathological examination of transverse and longitudinal sections of the parasitized ovaries showed nematodes at different stages of development among oocytes, but no indication of any associated inflammatory reaction. The presence of nematodes in the ovaries of bluefish is an important indication of fish hygiene, and parasitized fish are usually rejected by consumers because of their repugnant appearance.


Assuntos
Doenças dos Peixes/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Ovário/parasitologia , Perciformes/parasitologia , Animais , Brasil/epidemiologia , Feminino , Doenças dos Peixes/epidemiologia , Estágios do Ciclo de Vida , Nematoides/classificação , Infecções por Nematoides/epidemiologia
9.
Clin Radiol ; 72(11): 994.e1-994.e8, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28673445

RESUMO

AIM: To evaluate retrospectively the impact of injection flow rate on arterial phase image degradation in liver magnetic resonance imaging (MRI) with gadoxetic acid (Gd-EOB-DTPA) compared to gadobutrol. MATERIALS AND METHODS: Two hundred consecutive patients who had undergone liver MRI were enrolled in this Health Insurance Portability and Accountability Act (HIPAA)-compliant institutional review board (IRB)-approved study and were divided into three groups. Group 1 (50 patients) and 2 (50 patients) had undergone MRI performed with gadoxetic acid (fixed 10 ml) at flow rate of 1 and 2 ml/s, respectively. Group 3 (100 patients) had undergone MRI performed with gadobutrol (0.1 mmol/kg) at 1 ml/s. Precontrast and post-contrast (arterial, portal venous, and hepatic venous phases) image degradation was assessed by two blinded independent readers using a four-point rating scale. The numbers of patients with arterial phase image degradation were compared using the Fisher exact test among the three groups. RESULTS: The incidence of arterial phase image degradation was 12% (6/50) in group 1 and 16% (8/50) in group 2 for both readers, 6% (6/100) for reader 1 and 5% (5/100) for reader 2 in group 3. Group 2 had a higher incidence of arterial phase image degradation when compared with group 3 for reader 2 (p=0.032). Severe arterial phase image degradation, resulting in non-diagnostic image quality, occurred in 4% (2/50) of patients when performed with gadoxetic acid administration at 2 ml/s and 2% (1/50) at 1 ml/s. CONCLUSION: A slower injection flow rate has a trend to reduce the incidence and severity of arterial phase image degradation during liver MRI with gadoxetic acid when compared to gadobutrol.


Assuntos
Meios de Contraste/farmacocinética , Gadolínio DTPA/farmacocinética , Aumento da Imagem/métodos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos/farmacocinética , Adolescente , Adulto , Idoso , Meios de Contraste/administração & dosagem , Feminino , Gadolínio DTPA/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/administração & dosagem , Estudos Retrospectivos , Adulto Jovem
10.
Kathmandu Univ Med J (KUMJ) ; 15(57): 62-66, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29446365

RESUMO

Background Identification is of utmost importance in any medicolegal investigation with sex determination being one of the principle indicators of identity. Sexing of bones becomes easy when the skeletal remains are complete. However, the problem arises when the bones are fragmented. Many researchers have undertaken several studies in different populations to determine the sex with reasonable accuracy using numerous measurements of the skull including those of the foramen magnum. Objective The present study was aimed to find the sexual dimorphism of the foramen magnum in the Nepalese population by analyzing the antero-posterior length, transverse diameter and area of the foramen magnum. Method The antero-posterior length and transverse diameter of the foramen magnum were measured using three-dimensional computed tomography (3DCT) images of the head in a cohort of 100 Nepalese subjects. Radinsky's and Teixeria's formulae were used to calculate the area of the foramen magnum. Discriminate function analysis was used to analyze sex differences. Result Mean values of antero-posterior length and transverse diameter of the foramen magnum in males were higher than in females. The mean of the area calculated using Radinsky's formula was smaller than that calculated by Teixeira's formula and the areas calculated were higher in males. The measurements of the foramen magnum and the areas calculated showed significant difference (p<0.001) between males and females. Discriminate function analysis for the measurements of the foramen magnum and the areas calculated showed high predictability for both the sexes. Discriminate function analysis showed a maximum predictability of 75%. Conclusion Considering the percent of predictability of sex from the various variables related to the foramen magnum in the Nepalese population, it can be concluded that its restricted applicability in forensic investigations should be constrained to cases of fragmentary skull bases.


Assuntos
Forame Magno/anatomia & histologia , Determinação do Sexo pelo Esqueleto/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Discriminante , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Int J Biometeorol ; 60(7): 945-55, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26498437

RESUMO

Dynamic global vegetation models (DGVMs) simulate surface processes such as the transfer of energy, water, CO2, and momentum between the terrestrial surface and the atmosphere, biogeochemical cycles, carbon assimilation by vegetation, phenology, and land use change in scenarios of varying atmospheric CO2 concentrations. DGVMs increase the complexity and the Earth system representation when they are coupled with atmospheric global circulation models (AGCMs) or climate models. However, plant physiological processes are still a major source of uncertainty in DGVMs. The maximum velocity of carboxylation (Vcmax), for example, has a direct impact over productivity in the models. This parameter is often underestimated or imprecisely defined for the various plant functional types (PFTs) and ecosystems. Vcmax is directly related to photosynthesis acclimation (loss of response to elevated CO2), a widely known phenomenon that usually occurs when plants are subjected to elevated atmospheric CO2 and might affect productivity estimation in DGVMs. Despite this, current models have improved substantially, compared to earlier models which had a rudimentary and very simple representation of vegetation-atmosphere interactions. In this paper, we describe this evolution through generations of models and the main events that contributed to their improvements until the current state-of-the-art class of models. Also, we describe some main challenges for further improvements to DGVMs.


Assuntos
Modelos Teóricos , Fenômenos Fisiológicos Vegetais , Aclimatação , Dióxido de Carbono , Temperatura
12.
J Fish Biol ; 89(1): 280-314, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27401481

RESUMO

The relationships between fish composition, connectivity and morphometry of 103 lagoons in nine freshwater ecoregions (FEOW) between 2·83° S and 37·64° S were evaluated in order to detect possible congruence between the gradient of species richness and similarities of assemblage composition. Most lagoons included in the study were <2 km(2) , with a maximum of 3975 km(2) in surface area. Combined surface area of all lagoons included in the study was 5411 km(2) . Number of species varied locally from one to 76. A multiple regression revealed that latitude, attributes of morphometry and connectivity, and sampling effort explained a large amount of variability in species richness. Lagoon area was a good predictor of species richness except in low latitude ecoregions, where lagoons are typically small-sized and not affected by marine immigrants, and where non-native fish species accounted for a significant portion of species richness. Relationships between species and area in small-sized lagoons (<2 km(2) ) is highly similar to the expected number in each ecoregion, with systems located between 18·27° S and 30·15° S attaining higher levels of species richness. Similarities in species composition within the primary, secondary and peripheral or marine divisions revealed strong continental biogeographic patterns only for species less tolerant or intolerant to salinity. Further support for the FEOW scheme in the eastern border of South America is therefore provided, and now includes ecotonal systems inhabited simultaneously by freshwater and marine species of fishes.


Assuntos
Biodiversidade , Peixes , Animais , Oceano Atlântico , Água Doce , América do Sul
13.
Kathmandu Univ Med J (KUMJ) ; 14(55): 198-201, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28814678

RESUMO

Background One of the important components of forensic identification is sex determination. The prediction of sex becomes easy with a complete skeleton. The problem arises with mutilated and incomplete skeletal remains. The skull and pelvis are preferred for sex prediction, but not uncommonly, long bones are brought for forensic examination. The femur out stands as the most dimorphic long bone. The literature on sex determination from the femur in different population groups is in abundance. The forensic anthropology literature suggests that longitudinal dimensions are often less discriminating than the breadth and circumference of long bones. Many researchers have suggested that the bicondylar width of the femur is the most dimorphic dimension. Objective To evaluate the sexing potential of the bicondylar width of the femur in the Nepalese population using digital X-ray images. Method A sample of 200 digital X-ray images of the knee belonging to 100 males and 100 females was used to measure the bicondylar width of the right femur. These digital X-ray images were those of Nepalese patients who visited the Department of Radiology at the affiliate hospital of Kathmandu University School of Medical Sciences, Dhulikhel, Nepal for diagnostic and treatment purposes. Result The resent study reveals a statistically significant difference for the bicondylar width of the femur between males and females. A regression equation was derived with sectioning point 77.84. Using the regression equation the prediction of sex was 68% with an overlapping of 32%. Having a low prediction in comparison to other studies in different populations, 95% confidence interval for the mean was used to get a range of measurements of the bicondylar width for males and females. The range stated in the present study is 79.47 mm to 82.20 mm for males and 73.75 mm to 75.93 mm for females. Conclusion The bicondylar width of the femur cannot be individually recommended for sex determination in the Nepalese population, but could be considered if analyzed along with the other morphometric traits for sex determination.


Assuntos
Fêmur/anatomia & histologia , Antropologia Forense/métodos , Determinação do Sexo pelo Esqueleto/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nepal , Raios X , Adulto Jovem
14.
J Clin Pediatr Dent ; 39(2): 168-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25823487

RESUMO

Neurofibromatosis type 1 (NF1) is a common autosomal genetic disorder with a prevalence of 1 in 3,000 births. NF1 is a complex syndrome characterized by many abnormalities and may affect all organ systems. Oral manifestations of NF1 occur frequently, but reports including NF1 children with facial plexiform neurofibromas and oral alterations are scant. Facial plexiform neurofibroma may cause asymmetry, disfigurement and usually arises from the trigeminal nerve. The aim of this paper is to to report three pediatric NF1 cases with facial plexiform neurofibroma presenting with oral manifestations, which were evaluated clinically and radiographically, and also to briefly review the literature. Patients presented with changes in the oral soft tissues, jaws, and teeth ipsilateral to the tumor.


Assuntos
Deformidades Dentofaciais/diagnóstico , Neoplasias Faciais/diagnóstico , Neurofibroma Plexiforme/diagnóstico , Neurofibromatose 1/diagnóstico , Criança , Feminino , Neoplasias Gengivais/diagnóstico , Crescimento Excessivo da Gengiva/diagnóstico , Humanos , Macroglossia/diagnóstico , Masculino , Má Oclusão/diagnóstico , Mandíbula/anormalidades , Côndilo Mandibular/anormalidades , Neoplasias da Língua/diagnóstico
15.
J Appl Microbiol ; 117(2): 390-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24848589

RESUMO

AIMS: Dinoponera quadriceps venom (DqV) was examined to evaluate the antibacterial activity and its bactericidal action mechanism against Staphylococcus aureus. METHODS AND RESULTS: DqV was tested against a standard strain of methicillin-sensitive Staphylococcus aureus (MSSA), Staph. aureus ATCC 6538P and two standard strains of methicillin-resistant Staphylococcus aureus (MRSA), Staph. aureus ATCC 33591 and Staph. aureus CCBH 5330. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), the rate of kill and pH sensitivity of the DqV were determined by microdilution tests. Bactericidal and inhibitory concentrations of DqV were tested to check its action on Staph. aureus membrane permeability and cell morphology. The MIC and MBC of DqV were 6·25 and 12·5 µg ml(-1) for Staph. aureus ATCC 6538P, 12·5 and 50 µg ml(-1) for Staph. aureus CCBH 5330 and 100 and 100 µg ml(-1) for Staph. aureus ATCC 33591, respectively. Complete bacterial growth inhibition was observed after 4 h of incubation with the MBC of DqV. A lowest MIC was observed in alkaline pH. Alteration in membrane permeability was observed through the increase in crystal violet uptake, genetic material release and morphology in atomic force microscopy. CONCLUSIONS: The results suggest antibacterial activity of DqV against Staph. aureus and that the venom acts in the cell membrane. SIGNIFICANCE AND IMPACT OF THE STUDY: Alteration in membrane permeability may be associated with the antimicrobial activity of hymenopteran venoms.


Assuntos
Venenos de Formiga/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Formigas
16.
Genet Mol Res ; 13(1): 89-94, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24446290

RESUMO

Angiopolybia pallens is a swarm-founding wasp that occurs in Atlantic and Amazonian rainforests, which have been isolated from each other by a large arid corridor in central Brazil since the Tertiary. In this study, we used data from polymerase chain reaction-restriction fragment length polymorphism of 16S rDNA to infer some aspects of the genetic diversity and evolutionary history of this social wasp population. Samples collected across the species range in both rainforests showed remarkable differences that separated them into two distinct haplogroups. However, some samples from isolated areas in northeastern Bahia were more related to Amazonian lineages than to southern Bahia populations. Vicariant divergenc is discussed under South American rainforests biogeographical proposals.


Assuntos
Ecossistema , Polimorfismo Genético , Vespas/genética , Animais , Brasil , Evolução Molecular , Haplótipos , Filogeografia , RNA Ribossômico 16S/genética
17.
Vet Pathol ; 50(4): 582-4, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22961885

RESUMO

The stomachs of 100 free-ranging black caimans (Melanosuchus niger Spix, 1825) from the Mamirauá Sustainable Development Reserve, Amazonas state, Brazil, were examined for parasitism and pathologic lesions. All animals were harvested for human consumption. Ascaridoid nematodes were found in 67 caimans and were identified as Brevimulticaecum sp. These parasites were associated with focally extensive, chronic gastric ulcers and formation of localized intramural granulomas containing nematodes. All caiman were in good nutritional condition, which suggests that effects of gastric nematodiasis on the crocodilian hosts were minimal at the time of slaughter.


Assuntos
Jacarés e Crocodilos/parasitologia , Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Granuloma/veterinária , Úlcera Gástrica/veterinária , Animais , Infecções por Ascaridida/patologia , Brasil , Doença Crônica , Granuloma/parasitologia , Granuloma/patologia , Humanos , Masculino , Estômago/parasitologia , Estômago/patologia , Úlcera Gástrica/parasitologia , Úlcera Gástrica/patologia
18.
Forensic Sci Rev ; 35(1): 47-57, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36575372

RESUMO

The COVID-19 pandemic has affected millions of people around the world either directly or indirectly. Deaths have been attributed to COVID-19 as the underlying cause of death or as a contributing cause of death. It is estimated that millions of excess deaths were associated with the COVID-19 pandemic in 2020 and 2021. The importance of a clinical autopsy on COVID-19 corpses lies in understanding the pathogenesis of the disease better. Moreover, a forensic autopsy may be performed on a COVID-19-infected corpse when indicated for medico-legal purposes. From the autopsy perspective, handling COVID-19-infected corpses requires specific guidelines and safety measures to be followed to limit the transmission of SARS-CoV-2, the causative virus. This is essential as COVID-19 is an emerging infectious disease caused by a newly discovered virus. This review narrates the safety measures that should be followed at different stages of handling COVID-19 corpses, starting from the death scene to burial and funeral. Ethical issues in handling COVID-19 corpses are also briefed in this review. As COVID-19 can be transmitted through infected bodies, it is crucial to wear recommended personal protective equipment, specifically for aerosol-generating procedures. There are specific safety measures to be considered before transporting the body to the mortuary, with particular requirements to be implemented there, such as specific engineering controls, staff training, and autopsy room precautions. After conducting the autopsy, disinfection of the tools and equipment, body bags, transport vehicles, and the autopsy room should be considered.


Assuntos
COVID-19 , Humanos , Autopsia , SARS-CoV-2 , Pandemias , Aerossóis e Gotículas Respiratórios , Cadáver
19.
Auton Neurosci ; 246: 103073, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36736078

RESUMO

AIMS: In rats, stress-induced hyperthermia caused by social interaction depends on brown adipose tissue (BAT) thermogenesis and peripheral vasoconstriction. However, the peripheral mechanisms responsible for regulating the level of hyperthermia during social stress are still unknown. The transient receptor potential vanilloid 1 (TRPV1) subfamily, expressed in sensory and visceral neurons, can serve as a thermoreceptor. Here, we tested the hypothesis that the abdominal TRPV1 is essential in regulating stress-induced hyperthermia during social stress. MAIN METHODS: Male Wistar rats received an intraperitoneal injection of Resiniferatoxin (RTX) - an ultra-potent capsaicin analog, (i.e., to desensitize the TRPV1 channels) or vehicle. Seven days later, we evaluated the effects of abdominal TRPV1 channels desensitization on core body temperature (CBT), brown adipose tissue (BAT) temperature, tail skin temperature, and heart rate (HR) of rats subjected to a social stress protocol. KEY FINDINGS: We found abdominal TRPV1 desensitization increased CBT and BAT temperature but did not change tail skin temperature and HR during rest. However, under social stress, we found that abdominal TRPV1 desensitization heightened the increase in CBT and BAT caused by stress. Also, it abolished the increase in tail skin temperature that occurs during and after social stress. TRPV1 desensitization also delayed the HR recovery after the exposure to the social stress. SIGNIFICANCE: These results show that abdominal TRPV1 channels desensitization heightens stress-induced hyperthermia, causing heat dissipation during and after social stress, enabling optimal thermal control during social encounters.


Assuntos
Hipertermia Induzida , Canais de Cátion TRPV , Animais , Masculino , Ratos , Capsaicina/farmacologia , Ratos Sprague-Dawley , Ratos Wistar , Canais de Cátion TRPV/fisiologia
20.
J Nutr Health Aging ; 27(10): 878-884, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37960911

RESUMO

IMPORTANCE: Aging generates changes over the years. Because of this, the musculoskeletal system is directly degraded and suffer deficits in its performance in elderly patients with Sarcopenia, as this condition is characterized by a decrease in muscle mass and function. OBJECTIVE: Correlate the motor reaction time and functional skills of non-sarcopenic, pre-sarcopenic and sarcopenic elderly women, and analyze influence on the risk of falls. DESIGN: Cross-sectional observational analytical study, following the methodological strategies of STROBE (Strengthening the Reporting of Observational Studies in Epidemiology), carried out under the approval of the Research Ethics Committee of the Unievangélica University, no. 3.694.235/2019. SETTING: Participants were evaluated regarding: cognitive status, level of physical activity, fear of falling, body composition, motor reaction time, static and dynamic balance, gait kinetics, strength and endurance of the lower limbs and finally handgrip strength. PARTICIPANTS: A total of 59 volunteer elderly women were assessed following the diagnostic criteria for sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP). RESULTS: The results show that there was a greater difference in motor reaction time between the non-sarcopenic and sarcopenic elderly women due to the executing organ being damaged by the presence of sarcopenia, causing motor response to slowdown. Functional deficit, fear of falling and greater risk of falls were observed in the sarcopenic group, under the harmful influence of increased motor reaction time. CONCLUSION: Sarcopenic elderly women present increased motor reaction time, that is, slowed motor responses due to decreased muscle mass, strength and impaired musculature, which generate functional deficits that contribute to an increased risk of falls.


Assuntos
Sarcopenia , Idoso , Feminino , Humanos , Acidentes por Quedas , Estudos Transversais , Medo , Força da Mão/fisiologia , Tempo de Reação , Sarcopenia/diagnóstico
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