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We report on an all-fiber setup capable of generating complex intensity patterns using interference of few guided modes. Comprised by a few-mode fiber (FMF) spliced to a multimodal interference (MMI) fiber device, the setup allows for obtaining different output patterns upon adjusting the phases and intensities of the modes propagating in the FMF. We analyze the output patterns obtained when exciting two family modes in the MMI device using different phase and intensity conditions for the FMF modal base. Using this simple experimental arrangement we are able to produce complex intensity patterns with radial and azimuthal symmetry. Moreover, our results suggest that this approach provides a means to generate beams with orbital angular momentum (OAM).
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Gut bacterial communities have been shown to be influenced by diet, host phylogeny and anatomy, but most of these studies have been done in captive animals. Here we compare the bacterial communities in the digestive tract of wild birds. We characterized the gizzard and intestinal microbiota among 8 wild Neotropical bird species, granivorous or frugivorous species of the orders Columbiformes and Passeriformes. We sequenced the V4 region of the 16S rRNA gene in 94 collected samples from 32 wild birds from 5 localities, and compared bacterial communities by foraging guild, organ, locality and bird taxonomy. 16S rRNA gene-based sequencing data were examined using QIIME with linear discriminant analysis effect size (LEfSe) and metabolic pathways were predicted using PICRUSt algorism. We identified 8 bacterial phyla, dominated by Firmicutes, Actinobacteria and Proteobacteria. Beta diversity analyses indicated significant separation of gut communities by bird orders (Columbiformes vs. Passerifomes) and between bird species (p<0.01). In lower intestine, PICRUSt shows a predominance of carbohydrate metabolism in granivorous birds and xenobiotics biodegradation pathways in frugivorous birds. Gizzard microbiota was significantly richer in granivorous, in relation to frugivorous birds (Chao 1; non-parametric t-test, p<0.05), suggesting a microbial gizzard function, beyond grinding food. The results suggest that the most important factor separating the bacterial community structure was bird taxonomy, followed by foraging guild. However, variation between localities is also likely to be important, but this could not been assessed with our study design.
Assuntos
Animais Selvagens/microbiologia , Columbiformes/microbiologia , Microbioma Gastrointestinal , Moela das Aves/patologia , Passeriformes/microbiologia , Gastropatias/patologia , Algoritmos , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Análise Discriminante , Moela das Aves/microbiologia , Intestinos/microbiologia , Análise de Componente Principal , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA , Gastropatias/microbiologia , Gastropatias/veterináriaRESUMO
The Vibrionaceae are Gram-negative bacteria present in marine and estuarine environments worldwide, including several species known as important pathogens to humans and aquatic organisms. The aim of this research was to investigate the occurrence and virulence properties of Vibrio and Salinivibrio isolated from lagoons at Cuare Wildlife Refuge and Margarita Island in the southern Caribbean Sea. Water, plankton and oyster samples were collected during October 2011 and March 2012 and examined by specific PCR and culture methods. Vibrio genus DNA was detected in 95% of samples, while the intergenic spacer region (ISR) of Vibrio cholerae and the genes that code for the thermolabile direct haemolysin (tl) of Vibrio parahaemolyticus and the haemolysin/cytolysin (vvhA) of Vibrio vulnificus were absent or amplified in low proportions (23, 5, and 0%, respectively). Nine isolates from water and plankton were confirmed as Vibrio or Salinivibrio by phenotypic tests, 16S rRNA gene sequencing and phylogenetic analysis. All the isolates presented similar patterns of virulence factors, in which the genes ctxA (encoding for cholera toxin), tl and vvhA were lacking, whereas seven isolates displayed antibiotic resistance against ampicillin and cephalosporins. The 16S rRNA phylogenetic analysis showed the clustering of Vibrio isolates in three main clades: the plankton isolate from Cuare Wildlife Refuge formed a group with V. cholerae and Vibrio mimicus while the Margarita isolates clustered with sequences from the harveyi clade and Salinivibrio. This is the first time that Salinivibrio species are reported in tropical lagoons of the Caribbean Sea with antibiotic resistance.
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Vibrio/patogenicidade , Microbiologia da Água , Animais , Região do Caribe , Humanos , Filogenia , RNA Ribossômico 16S , Água do Mar , Clima Tropical , Vibrio/genética , Vibrio/isolamento & purificação , VirulênciaRESUMO
Vibrio cholerae represents a significant threat to human health in developing countries. This pathogen forms biofilms which favors its attachment to surfaces and its survival and transmission by water or food. This work evaluated the in vitro biofilm formation of V. cholerae isolated from clinical and environmental sources on stainless steel of the type used in food processing by using the environmental scanning electron microscopy (ESEM). Results showed no cell adhesion at 4 h and scarce surface colonization at 24 h. Biofilms from the environmental strain were observed at 48 h with high cellular aggregations embedded in Vibrio exopolysaccharide (VPS), while less confluence and VPS production with microcolonies of elongated cells were observed in biofilms produced by the clinical strain. At 96 h the biofilms of the environmental strain were released from the surface leaving coccoid cells and residual structures, whereas biofilms of the clinical strain formed highly organized structures such as channels, mushroom-like and pillars. This is the first study that has shown the in vitro ability of V. cholerae to colonize and form biofilms on stainless steel used in food processing.
Assuntos
Biofilmes/crescimento & desenvolvimento , Manipulação de Alimentos , Aço Inoxidável , Vibrio cholerae/crescimento & desenvolvimento , Humanos , Microscopia Eletrônica de Varredura , Vibrio cholerae/efeitos dos fármacosRESUMO
BACKGROUND: The Cariaco Basin is characterized by pronounced and predictable vertical layering of microbial communities dominated by reduced sulfur species at and below the redox transition zone. Marine water samples were collected in May, 2005 and 2006, at the sampling stations A (10°30' N, 64°40' W), B (10°40' N, 64°45' W) and D (10°43'N, 64°32'W) from different depths, including surface, redox interface, and anoxic zones. In order to enrich for sulfate reducing bacteria (SRB), water samples were inoculated into anaerobic media amended with lactate or acetate as carbon source. To analyze the composition of enrichment cultures, we performed DNA extraction, PCR-DGGE, and sequencing of selected bands. RESULTS: DGGE results indicate that many bacterial genera were present that are associated with the sulfur cycle, including Desulfovibrio spp., as well as heterotrophs belonging to Vibrio, Enterobacter, Shewanella, Fusobacterium, Marinifilum, Mariniliabilia, and Spirochaeta. These bacterial populations are related to sulfur coupling and carbon cycles in an environment of variable redox conditions and oxygen availability. CONCLUSIONS: In our studies, we found an association of SRB-like Desulfovibrio with Vibrio species and other genera that have a previously defined relevant role in sulfur transformation and coupling of carbon and sulfur cycles in an environment where there are variable redox conditions and oxygen availability. This study provides new information about microbial species that were culturable on media for SRB at anaerobic conditions at several locations and water depths in the Cariaco Basin.
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Helicobacter pylori is the main bacterial agent implicated in human gastroduodenal inflammatory pathologies; being one of the most common bacterial pathogens, with a high prevalence in Venezuela. The diagnosis of H. pylori infection is performed primarily in gastric biopsies through PCR; however, string-absorbed gastric juice and esophageal biopsies could be also used as alternative specimens to determine the infection. In this study the H. pylori infection was assessed in different specimens of the upper tract digestive of dyspeptic patients, though the detection by PCR of essential genes (glmM and ureA) and genes encoding virulence factors (cagA). Of 104 patients studied, H. pylori was found in 53.8, 69,2 and 58,7% of gastric juice, and gastric and esophageal biopsies, respectively; with predominance of the strains type I (cagA+) in juice and gastric biopsies, and strains type II (cagA-) in esophageal biopsies. The detection of H. pylori in gastric juice and esophageal biopsies showed high sensitivity and specificity, in comparison with the detection in gastric biopsies, suggesting that both types of specimens may be used efficiently for a secure diagnosis of H. pylori infection.
Assuntos
Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Adolescente , Adulto , Idoso , Biópsia , DNA Bacteriano/análise , Dispepsia/microbiologia , Esôfago/patologia , Suco Gástrico/química , Infecções por Helicobacter/complicações , Helicobacter pylori/genética , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estômago/patologia , Adulto JovemRESUMO
Helicobacter pylori es el principal agente bacteriano implicado en lesiones gastroduodenales inflamatorias en humanos y una de las bacterias patógenas más comunes, con una alta prevalencia en Venezuela. El diagnóstico de la infección por H. pylori se realiza frecuentemente en biopsias gástricas mediante PCR; sin embargo, el jugo gástrico y las biopsias esofágicas podrían también ser utilizadas como muestras alternativas para determinar la infección. En el presente trabajo se evalúo la infección por H. pylori en diferentes muestras del tracto digestivo superior de pacientes dispépticos, mediante la detección por PCR de genes esenciales (glmM y ureA) y de virulencia (cagA). De los 104 pacientes estudiados, H. pylori fue encontrado en 53,8; 69,2 y 58,7% de las muestras de jugo gástrico y biopsias gástricas y esofágicas, respectivamente, con una predominancia de cepas tipo I (cagA+) en jugo y biopsias gástricas y cepas tipo II (cagA-) en biopsias esofágicas. La detección de H. pylori en jugo gástrico y biopsias esofágicas mostró una alta sensibilidad y especificidad en relación a la detección en biopsias gástricas, lo cual sugiere que ambos tipos de muestras pueden ser utilizados eficazmente para un diagnóstico seguro de la infección por H. pylori.
Helicobacter pylori is the main bacterial agent implicated in human gastroduodenal inflammatory pathologies; being one of the most common bacterial pathogens, with a high prevalence in Venezuela. The diagnosis of H. pylori infection is performed primarily in gastric biopsies through PCR; however, string-absorbed gastric juice and esophageal biopsies could be also used as alternative specimens to determine the infection. In this study the H. pylori infection was assessed in different specimens of the upper tract digestive of dyspeptic patients, though the detection by PCR of essential genes (glmM and ureA) and genes encoding virulence factors (cagA). Of 104 patients studied, H. pylori was found in 53.8, 69,2 and 58,7% of gastric juice, and gastric and esophageal biopsies, respectively; with predominance of the strains type I (cagA+) in juice and gastric biopsies, and strains type II (cagA-) in esophageal biopsies. The detection of H. pylori in gastric juice and esophageal biopsies showed high sensitivity and specificity, in comparison with the detection in gastric biopsies, suggesting that both types of specimens may be used efficiently for a secure diagnosis of H. pylori infection.
Assuntos
Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Helicobacter pylori , Infecções por Helicobacter/diagnóstico , Biópsia , DNA Bacteriano/análise , Dispepsia/microbiologia , Esôfago/patologia , Suco Gástrico/química , Infecções por Helicobacter/complicações , Helicobacter pylori/genética , Reação em Cadeia da Polimerase , Estômago/patologiaRESUMO
The capybara (Hydrochoerus hydrochaeris) is the world's largest living rodent. Native to South America, this hindgut fermenter is herbivorous and coprophagous and uses its enlarged cecum to digest dietary plant material. The microbiota of specialized hindgut fermenters has remained largely unexplored. The aim of this work was to describe the composition of the bacterial community in the fermenting cecum of wild capybaras. The analysis of bacterial communities in the capybara cecum is a first step towards the functional characterization of microbial fermentation in this model of hindgut fermentation. We sampled cecal contents from five wild adult capybaras (three males and two females) in the Venezuelan plains. DNA from cecal contents was extracted, the 16S rDNA was amplified, and the amplicons were hybridized onto a DNA microarray (G2 PhyloChip). We found 933 bacterial operational taxonomic units (OTUs) from 182 families in 21 bacterial phyla in the capybara cecum. The core bacterial microbiota (present in at least four animals) was represented by 575 OTUs. About 86% of the cecal bacterial OTUs belong to only five phyla, namely, Firmicutes (322 OTUs), Proteobacteria (301 OTUs), Bacteroidetes (76 OTUs), Actinobacteria (69 OTUs), and Sphirochaetes (37 OTUs). The capybara harbors a diverse bacterial community that includes lineages involved in fiber degradation and nitrogen fixation in other herbivorous animals.
Assuntos
Bactérias/genética , Ceco/microbiologia , Metagenoma , Roedores/microbiologia , Animais , Animais Selvagens/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
O objetivo deste trabalho foi avaliar eficiência da utilização de lidocaína por via intratecal, associada à anestesia prévia com thiopental sódico endovenoso, como método de eutanásia em eqüinos com diferentes graus de consciência e condição clínica. Foi utilizada a rotina clinica do HCV-UFPel, onde foram avaliados 22 eqüinos os quais apresentavam indicação de eutanásia. Foi realizado exame clínico geral e específico, classificando a condição clínica e grau de consciência, numa escala de 1 a 3. Foi monitorado o tempo para ocorrência de parada cardíaca e a ocorrência de reações durante o período trans-eutanásia. O tempo para parada cardíaca não foi influenciado pela classificação clínica, tipo de doença ou dose do tiopental sódico. Foi observado que quanto maior o volume de lidocaína utilizada por via intratecal, menor é o tempo para parada cardíaca (p 0,05). A análise histopatológica do sistema nervoso central pós-eutanásia demonstrou que a técnica não causou lesões macro e microscópicas. Assim, a utilização da lidocaína via intratecal associada a pré anestesia com tiopental sódico, mostrou-se eficaz na eutanásia de eqüinos, proporcionando uma inconsciência rápida, com discretas reações e insensibilidade, além de não conferir lesões ao sistema nervoso central. SummaryThe aim of this study was to evaluate the efficiency of intrathecal lidocaine preceded by pre-anesthesia us
RESUMO
O objetivo deste trabalho foi avaliar eficiência da utilização de lidocaína por via intratecal, associada à anestesia prévia com thiopental sódico endovenoso, como método de eutanásia em eqüinos com diferentes graus de consciência e condição clínica. Foi utilizada a rotina clinica do HCV-UFPel, onde foram avaliados 22 eqüinos os quais apresentavam indicação de eutanásia. Foi realizado exame clínico geral e específico, classificando a condição clínica e grau de consciência, numa escala de 1 a 3. Foi monitorado o tempo para ocorrência de parada cardíaca e a ocorrência de reações durante o período trans-eutanásia. O tempo para parada cardíaca não foi influenciado pela classificação clínica, tipo de doença ou dose do tiopental sódico. Foi observado que quanto maior o volume de lidocaína utilizada por via intratecal, menor é o tempo para parada cardíaca (p < 0,05). A análise histopatológica do sistema nervoso central pós-eutanásia demonstrou que a técnica não causou lesões macro e microscópicas. Assim, a utilização da lidocaína via intratecal associada a pré anestesia com tiopental sódico, mostrou-se eficaz na eutanásia de eqüinos, proporcionando uma inconsciência rápida, com discretas reações e insensibilidade, além de não conferir lesões ao sistema nervoso central. SummaryThe aim of this study was to evaluate the efficiency of intrathecal lidocaine preceded by pre-anesthesia us
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The aim of this study was to evaluate the efficiency of intrathecal lidocaine preceded by pre-anesthesia using intravenous sodium thiopental as euthanasia protocol in horses presenting different degrees of awareness and clinical condition. Twenty two horses that were admitted to the HCV-UFPel and sent to euthanasia after clinical evaluation, were used in the study. Clinical general and specific examinations were performed to classify the horses according to their clinical condition and level of consciousness on a scale from 1 to 3. The time to cardiac arrest and other reactions during euthanasia was monitored. The moment of cardiac arrest was not influenced by clinical condition, disease or dose of sodium thiopental. It was observed that the higher the volume of intrathecal lidocaine, the shorter the time to cardiac arrest (P<0.05). The post-euthanasia histopathological analysis of the central nervous system indicated that this technique did not cause macro or microscopic injuries to the tissue. Thus, intrathecally lidocaine associated with sodium thiopental pre-anesthesia was effective as equine euthanasia protocol, since it promoted rapid unconsciousness with mild reactions and insensitivity, without causing injuries in the central nervous system as well.
O objetivo deste trabalho foi avaliar eficiência da utilização de lidocaína por via intratecal, associada à anestesia prévia com thiopental sódico endovenoso, como método de eutanásia em equinos com diferentes graus de consciência e condição clínica. Foi utilizada a rotina clinica do HCV-UFPel, onde foram avaliados 22 eqüinos os quais apresentavam indicação de eutanásia. Foi realizado exame clínico geral e específico, classificando a condição clínica e grau de consciência, numa escala de 1 a 3. Foi monitorado o tempo para ocorrência de parada cardíaca e a ocorrência de reações durante o período trans-eutanásia. O tempo para parada cardíaca não foi influenciado pela classificação clínica, tipo de doença ou dose do tiopental sódico. Foi observado que quanto maior o volume de lidocaína utilizada por via intratecal, menor é o tempo para parada cardíaca (p<0,05). A análise histopatológica do sistema nervoso central pós-eutanásia demonstrou que a técnica não causou lesões macro e microscópicas. Assim, a utilização da lidocaína via intratecal associada a pré anestesia com tiopental sódico, mostrou-se eficaz na eutanásia de equinos, proporcionando uma inconsciência rápida, com discretas reações e insensibilidade, além de não causar lesões ao sistema nervoso central.
Assuntos
Animais , Tiopental/administração & dosagem , Eutanásia Animal/métodos , Cavalos , Lidocaína/administração & dosagem , Injeções Espinhais/veterinária , AnestésicosRESUMO
Helicobacter spp. occur in the digestive system of a broad range of animal taxa, including marine mammals. Only one formally recognized species, Helicobacter cetorum, has been described in marine mammals. Helicobacter has not been reported in the Atlantic spotted dolphin (Stenella frontalis). The purpose of our study was to examine the digestive tract of a stranded spotted dolphin for Helicobacter. Tissue and content samples were collected at necropsy and examined by histopathology and molecular analyses using Helicobacter genus-specific 16S rDNA polymerase chain reaction (PCR) and DNA sequencing. Helicobacter was detected in all stomach divisions and the duodenal ampulla. A sequence type of the 16S rRNA gene shared a 98-99% identity to sequences from H. cetorum. This study reports for the first time Helicobacter in S. frontalis.
Assuntos
DNA Bacteriano/análise , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Stenella/microbiologia , Animais , DNA Ribossômico/análise , Duodeno/microbiologia , Duodeno/patologia , Helicobacter/classificação , Helicobacter/genética , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estômago/microbiologia , Estômago/patologiaRESUMO
The aim of this study was to characterize the virulence properties and the antimicrobial resistance of Vibrio cholerae isolates from a coastal area of the Caribbean Sea. Three V. cholerae isolates were obtained from seawater and plankton using the HP selective medium for Helicobacter pylori. These V. cholerae isolates belonged to the non-O1, non-O139 serogroups and they did not have cholera toxin genes. They were resistant to penicillins and some cephalosporins and were sensitive to netilmicin, tetracyclines, sulfamethoxazole-trimethoprim and quinolones. This is the first study that provides biochemical and molecular evidence of non-O1, non-O139 V. cholerae isolates, non-toxigenic, carrying antibiotic resistance in seawater and plankton from a coastal area of the Caribbean Sea.
Assuntos
Antibacterianos/farmacologia , Vibrio cholerae/isolamento & purificação , Microbiologia da Água , Região do Caribe , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Plâncton/microbiologia , Água do Mar/microbiologia , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/patogenicidade , VirulênciaRESUMO
We consider the electronic transport through a Rashba quantum dot coupled to ferromagnetic leads. We show that the interference of localized electron states with resonant electron states leads to the appearance of the Fano-Rashba effect. This effect occurs due to the interference of bound levels of spin-polarized electrons with the continuum of electronic states with an opposite spin polarization. We investigate this Fano-Rashba effect as a function of the applied magnetic field and Rashba spin-orbit coupling.
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AIMS: To assess the presence of Helicobacter DNA in the gastric mucosa Thoroughbred horses. METHODS AND RESULTS: Squamous and glandular mucosa samples were collected from 20 Thoroughbreds. None of these horses had shown any clinical symptoms of gastrointestinal disease. Necropsy tissues were analysed using histopathological techniques and a Helicobacter genus-specific PCR assay followed by sequencing of the amplicons. Seven horses were diagnosed with gastric ulceration, five with gastritis and six with both pathologies. Only two horses had a healthy gastric mucosa. Helicobacter-like DNA was detected in two out of seven horses with gastric ulcers, three out of five horses with gastritis, five out of six horses with both pathologies and one horse with normal gastric mucosa. The sequences of 1195 and 1237 bp fragments of the 16S rRNA gene shared 99% identity with the Helicobacter pylori 16S rRNA gene. However, all the samples were negative when tested with H. pylori-specific PCR assays targeting the cagA and glmM genes. CONCLUSIONS: The Helicobacter genus might colonize the gastric mucosa of horses. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of Helicobacter-like DNA in the gastric mucosa of horses and the pathogenic potential of these organisms requires further investigation.
Assuntos
DNA Bacteriano/análise , Mucosa Gástrica/microbiologia , Gastrite/veterinária , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Doenças dos Cavalos/microbiologia , Cavalos/microbiologia , Úlcera Gástrica/veterinária , Animais , DNA Ribossômico/análise , Mucosa Gástrica/patologia , Gastrite/microbiologia , Gastrite/patologia , Helicobacter/genética , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Doenças dos Cavalos/patologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Úlcera Gástrica/microbiologia , Úlcera Gástrica/patologiaRESUMO
BACKGROUND: The spectrum of human non-pylori Helicobacter infections is expanding, with species such as H. heilmannii and H. felis occasionally being associated with gastritis. However, the existence of non-pylori Helicobacter colonization in asymptomatic subjects has not been evaluated. The aim of this study was to investigate whether Helicobacter species other than pylori are present in the upper digestive tract of asymptomatic human subjects. MATERIALS AND METHODS: A Helicobacteraceae-specific semi-nested polymerase chain reaction (PCR) assay was used to detect Helicobacter-like organisms in the upper digestive tract of 91 Venezuelan volunteers (aged 18-68 years, 41 females, 50 males). Species were identified by denaturing gradient gel electrophoresis analysis and sequencing of the PCR products. RESULTS: We detected DNA sharing 99-100% sequence identity in over 300-400 bp with the 16S rRNA genes of H. pylori, H. cetorum, and Candidatus Wolinella africanus in 76%, 16%, and 15% of the subjects, respectively. Multiple colonization was documented in 10% of the subjects: H. cetorum and Candidatus W. africanus (4%), H. pylori and Candidatus W. africanus (4%), and H. pylori and H. cetorum (2%). CONCLUSIONS: Our results suggest that non-pylori Helicobacteraceae colonization is relatively common in the Venezuelan asymptomatic population. This is the first report documenting the presence of H. cetorum DNA in the human upper digestive tract, and the second report of the recently discovered Candidatus W. africanus.
Assuntos
Trato Gastrointestinal/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Helicobacter/epidemiologia , Helicobacter/isolamento & purificação , Wolinella/isolamento & purificação , Adolescente , Adulto , Idoso , DNA Bacteriano/análise , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/fisiopatologia , Helicobacter/classificação , Helicobacter/genética , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Especificidade da Espécie , Venezuela/epidemiologia , Wolinella/classificação , Wolinella/genéticaRESUMO
AIMS: This project investigated the utility of HP selective medium to isolate H. pylori cells from seawater and from marine molluscs. METHODS AND RESULTS: Nested-PCR was performed to reveal the presence of Helicobacter genus. All samples were cultured in HP selective medium and 16 cultures were initially selected as putative Helicobacter. Helicobacter spp. DNA were detected in 9/16 cultures and three of them had 99-100% homology to H. pylori based on 16S RNA gene sequence. Helicobacter pylori isolation was unsuccessful. On the basis of 16S RNA gene sequences the contaminating organisms were shown to be Proteus mirabilis and Vibrio cholerae. CONCLUSIONS: These results indicate the coexistence of three predominant bacterial genera in the cultures and that HP selective medium can grow other enteric bacteria besides Helicobacter. Additional assays will improve the HP selective medium formulation for marine samples avoiding P. mirabilis and V. cholerae interferents. SIGNIFICANCE AND IMPACT OF THE STUDY: This work shows the effectiveness of the selective HP medium for the Helicobacter culture from marine samples.
Assuntos
Meios de Cultura , Helicobacter pylori/isolamento & purificação , Ostreidae/microbiologia , Água do Mar/microbiologia , Animais , Técnicas Bacteriológicas , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Helicobacter pylori/classificação , Helicobacter pylori/genética , Helicobacter pylori/crescimento & desenvolvimento , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteus mirabilis/genética , Proteus mirabilis/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio cholerae/genética , Vibrio cholerae/isolamento & purificaçãoRESUMO
BACKGROUND/AIMS: Phytophotodermatitis (PPD) is defined as a phototoxic reaction of the skin after contact with substances derived from plants and subsequent exposure to sunlight. It is a frequent disease in our outpatient clinics during summer because of contact with Tahitian lemon. Our objectives were to experimentally reproduce PPD in rats, to identify whether PPD is induced by minimal exposure periods to sunlight, to find what kinds of lemons and which parts of the lemon (the fruit juice or the peel juice) may trigger the disease; to know whether the use of sunblock prevents the reaction; and to perform light microscopy of the lesions to describe their histology. METHODS: Adult rats (Rattus norwegicus), three in each experiment, were used. After painting the rats with the fruit juice or the peel juice they were exposed to sunlight for 2.5, 5, 7.5, and 10 min. Tahitian and Sicilian lemons were used in the experiments. Biopsies with 3-mm punches of different times of exposure were performed. RESULTS: The peel juice of both lemons reproduced PPD, which was clinically evident after 48 h. When the peel juice was alone applied there was no reaction; moreover, exposure to sunlight alone triggered no reaction. Two and a half minutes of exposure time was sufficient to induce phototoxic reaction, which was time dependent (the longer the exposure the more intense the reaction). Histopathological studies showed epithelial time-dependent vacuolar degeneration. The use of sunblock diminished the intensity of the reaction but did not prevent it. CONCLUSION: PPD can be reproduced in an animal model. It may be caused by the peel juice of Tahitian and Sicilian lemon. Because of an extremely short time of exposure (2.5 min) is sufficient to induce PPD it is necessary to alert the population, of the need for caution when handling lemons, especially outdoors despite using sunblock.
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Citrus/toxicidade , Dermatite Fototóxica/etiologia , Dermatite Fototóxica/patologia , Modelos Animais de Doenças , Frutas/toxicidade , Animais , Epitélio/patologia , Ratos , Fatores de Tempo , Vacúolos/patologiaRESUMO
The mechanisms involved in D-glucose and amino acid transport in the intestine of birds are still not clear. In chickens, D-glucose and amino acid absorption occurs via carrier-mediated transport, but in wild birds a passive paracellular mechanism seems to be the predominant pathway. The purpose of this work was to determine the existence of carrier-mediated sodium cotransport of D-glucose and L-alanine in the small intestine of Japanese quail (Coturnix coturnix), a granivorous bird. Intestinal transport was determined by changes in the short-circuit current (Isc), proportional to ion transmembrane flux, in the middle segment of the intestine of Japanese quail with a Ussing chamber. D-Glucose produced an increase of the Isc, and this effect was reverted by phloridzin, indicating the presence of a D-glucose transport mediated by the sodium/glucose cotranspoter 1. Addition of L-alanine also produced an increase of the Isc. We concluded that there is carrier-mediated cotransport of D-glucose and L-alanine with sodium in the small intestine of the Japanese quail.
Assuntos
Alanina/metabolismo , Coturnix/metabolismo , Glucose/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Condutividade Elétrica , Impedância Elétrica , Glucose/farmacologia , Absorção Intestinal/efeitos dos fármacos , Absorção Intestinal/fisiologia , Intestino Delgado/fisiologia , Masculino , Proteínas de Transporte de Monossacarídeos/efeitos dos fármacos , Proteínas de Transporte de Monossacarídeos/fisiologia , Florizina/farmacologiaRESUMO
El proceso de inmigración a nivel internacional ha sido asociado con altos grados de problemas psicológicos. Recientemente inclusive se ha determinado la existencia de síntomas de estrés pos-traumático (PTSD) entre los refugiados del sudeste de Asia. El presente estudio examinó primero el impacto de la inmigración en los niveles de depresión, ansiedad y estrés generalizado en una muestra de sujetos de Centroamérica y México. El segundo objetivo de este trabajo fue determinar la existencia de sintómas específicos de PTSD y su relación con las razones que los individuos tuvieron para migrar a los Estados Unidos. Se encontró que, comparados con los sujetos nacidos en Estados Unidos, los inmigrantes presentaban niveles altos de estrés generalizado; asimismo, las razones que éstos dieron de su inmigración estuvieron relacionadas con el diagnóstico del PTSD, El 52% de los centroamericanos refugiados de guerra llenaba el criterio del DSM-III para ser diagnosticados con PTSD. Los resultados se presentan y discuten con el objetivo de sensibilizar a los profesionales de la salud mental sobre la secuela de síntomas psicológicos relacionados con el proceso de inmigración forzada