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1.
Lett Appl Microbiol ; 66(3): 215-221, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29274087

RESUMEN

This study assess the quality of wastewater through the detection and quantification of important viruses causing gastroenteritis at different stages of the wastewater treatment process in an activated-sludge wastewater treatment plant with ultraviolet disinfection. Ten sampling events were carried out in a campaign along a period of 18 months collecting wastewater samples from the influent, after the activated-sludge treatment, and after the final disinfection with UV radiation. Samples were concentrated through ultracentrifugation and analysed using retro-transcription, PCR and real time quantitative PCR protocols, for detection and quantification of Group A Rotavirus (RVA), Human Astrovirus (HAstV), Norovirus Genogroup II (NoV GII) and Human Adenovirus (HAdV). HAdV (100%), NoV GII (90%), RVA (70%) and HAstV (60%) were detected in influent samples with concentration from 1·4 (NoV GII) to 8·0 (RVA) log10  gc l-1 . Activated-sludge treatment reached well quality effluents with low organic material concentration, although nonstatistical significant differences were registered among influent and postactivated sludge treatment samples, regarding the presence and concentration for most viruses. All post-UV samples were negative for NoV GII and HAstV, although RVA and HAdV were detected in 38% and 63% of those samples respectively, with concentration ranging from 2·2 to 5·5 and 3·1 to 3·4 log10  gc l-1 . SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that an activated-sludge wastewater treatment plant with UV disinfection reduces to levels below the detection limit those single-stranded RNA viruses as noroviruses and astroviruses and reach significant lower levels of rotaviruses and adenoviruses after the complete treatment process.


Asunto(s)
Adenovirus Humanos/efectos de la radiación , Desinfección/métodos , Enterovirus/efectos de la radiación , Mamastrovirus/efectos de la radiación , Norovirus/efectos de la radiación , Rotavirus/efectos de la radiación , Aguas del Alcantarillado/virología , Rayos Ultravioleta , Adenovirus Humanos/genética , Adenovirus Humanos/aislamiento & purificación , Brotes de Enfermedades/prevención & control , Enterovirus/genética , Enterovirus/aislamiento & purificación , Gastroenteritis/virología , Humanos , Mamastrovirus/genética , Mamastrovirus/aislamiento & purificación , Norovirus/genética , Norovirus/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Rotavirus/genética , Rotavirus/aislamiento & purificación , Uruguay , Purificación del Agua/métodos
2.
Lett Appl Microbiol ; 66(4): 313-320, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29330866

RESUMEN

This study aimed to assess anthropogenic impact of surrounding population in the Private Reserve of Natural Heritage at Pantanal, the world's largest freshwater wetland ecosystem located in the centre of South America. Viral aetiological agents of acute gastroenteritis as rotavirus A (RVA), noroviruses, human adenoviruses, klassevirus and of hepatitis, as hepatitis A virus, were investigated in different aquatic matrices. Annual collection campaigns were carried out from 2009 to 2012, alternating dry and rainy seasons. Viral particles present in the samples were concentrated by the adsorption-elution method, with negatively charged membranes, and detected by qualitative and quantitative PCR. From a total of 43 samples at least one virus was detected in 65% (28) of them. Viruses were detected in all matrices with concentrations ranging from 2 × 102 to 8·3 × 104 genome copies per litre. A significant higher RVA frequency was observed in the dry season. Our data revealing dissemination of human enteric viruses in water matrices both inside and outside the reserve could be useful to trace faecal contamination in the environment and to minimize the risk of infection by exposure of susceptible individuals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is part of a collaborative project designed to investigate the environmental and health conditions of the Private Reserve of Natural Heritage at Pantanal, the largest seasonally flooded wetland in the world. The project aimed to promote health and quality of human and wildlife extending technical-scientific knowledge about pathogens present in the region. By assessing the occurrence of human enteric viruses in different water matrices we demonstrated the anthropogenic impact of surrounding population and pointed out the potential risk of infection by exposure of susceptible individuals.


Asunto(s)
Adenoviridae/aislamiento & purificación , Enterovirus/aislamiento & purificación , Gastroenteritis/virología , Virus de la Hepatitis A/aislamiento & purificación , Norovirus/aislamiento & purificación , Parques Recreativos , Rotavirus/aislamiento & purificación , Enfermedades Transmitidas por el Agua/virología , Adenoviridae/genética , Antígenos Virales , Brasil/epidemiología , Ecosistema , Enterovirus/genética , Heces/virología , Agua Dulce/virología , Gastroenteritis/epidemiología , Virus de la Hepatitis A/genética , Humanos , Norovirus/genética , Lluvia/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Rotavirus/genética , Estaciones del Año , Microbiología del Agua , Enfermedades Transmitidas por el Agua/epidemiología
3.
J Appl Microbiol ; 120(5): 1427-35, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26784369

RESUMEN

AIMS: To determine the prevalence and molecular epidemiology of norovirus (NoV) genogroup I (GI) and GII in Uruguay. METHODS AND RESULTS: One hundred and sixteen sewage samples were collected in six cities (Bella Unión, Salto, Paysandú, Fray Bentos, Melo and Treinta y Tres) from March 2011 to April 2013, viruses were concentrated by ultracentrifugation and NoV studies were performed by semi-nested RT-PCR (partial capsid region). NoV were detected in samples from all the cities and detected in 72% (84/116) of the samples with nine of them belonging to GI, 48 to GII and 27 to both genogroups. Remarkably, a high genetic diversity was identified: GII.2 (n = 13), GII.4 (n = 13), GI.1 (n = 5), GI.4 (n = 5), GI.8 (n = 4), GII.13 (n = 4), GII.1 (n = 3), GII.6 (n = 3), GI.3 (n = 1), GI.5 (n = 1), GI.6 (n = 1), GII.3 (n = 1), GII.17 (n = 1). Interestingly, a complete replacement of GII.4 New Orleans 2009 by GII.4 Sydney 2012 variants during 2012 was evidenced. CONCLUSION: This study reveals a high circulation of different NoV GI and GII genotypes in sewage evidencing a replacement of GII.4 variants. SIGNIFICANCE AND IMPACT OF STUDY: This approach can be used as an indicator of the presence of a new GII.4 variant which can originate an increase in acute gastroenteritis outbreaks worldwide.


Asunto(s)
Variación Genética , Norovirus/genética , Aguas del Alcantarillado/virología , Infecciones por Caliciviridae/virología , Proteínas de la Cápside/genética , Ciudades , Monitoreo del Ambiente , Genotipo , Norovirus/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Uruguay
4.
J Appl Microbiol ; 121(6): 1519-1529, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27566664

RESUMEN

AIMS: To investigate the anti-HSV and anti-inflammatory effects of a standardized ethyl acetate extract (SEAE) prepared with the stem bark of Strychnos pseudoquina, along with two isolated compounds: quercetin 3-O-methyl ether (3MQ) and strychnobiflavone (SBF). METHODS AND RESULTS: The mechanisms of action were evaluated by different methodological strategies. SEAE and SBF affected the early stages of viral infection and reduced HSV-1 protein expression. Both flavonoids elicited a concentration-dependent inhibition of monocyte chemoattractant protein-1 (MCP-1), whereas 3MQ reduced the chemokine release more significantly than SBF. Conversely, both compounds stimulated the production of the cytokines TNF-α and IL-1-ß in LPS-stimulated cells, especially at the intermediate and the highest tested concentrations. CONCLUSIONS: SEAE and SBF interfered with various steps of HSV replication cycle, mainly adsorption, postadsorption and penetration, as well as with ß and γ viral proteins expression; moreover, a direct inactivation of viral particles was observed. Besides, both flavonoids inhibited MCP-1 selectively, a feature that may be beneficial for the development of new anti-HSV agents. SIGNIFICANCE AND IMPACT OF THE STUDY: The results indicated that the samples present anti-HSV and anti-inflammatory activities, at different levels, which is an interesting feature since cold and genital sores are accompanied by an inflammation process.


Asunto(s)
Antivirales/farmacología , Biflavonoides/farmacología , Herpesvirus Humano 1/efectos de los fármacos , Quercetina/análogos & derivados , Strychnos/química , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antivirales/química , Biflavonoides/química , Brasil , Línea Celular , Quimiocina CCL2/metabolismo , Chlorocebus aethiops , Citocinas/metabolismo , Herpesvirus Humano 1/fisiología , Humanos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Plantas Medicinales/química , Quercetina/química , Quercetina/farmacología , Células Vero
5.
Arch Virol ; 160(11): 2839-43, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26280526

RESUMEN

Canine norovirus (NoV) and astrovirus (AstV) were studied in 20 domestic sewage samples collected in two cities in Uruguay. Four samples were characterized as canine AstV after phylogenetic analysis clustering with strains detected in Italy and Brazil in 2008 and 2012, respectively. One sample was characterized as canine NoV and clustered with a strain detected in Hong Kong and recently classified as GVII. This study shows the occurrence of a canine NoV GVII strain for the first time in the American continent and also warns about possible zoonotic infection, since canine strains were detected in domestic sewage.


Asunto(s)
Infecciones por Astroviridae/veterinaria , Infecciones por Caliciviridae/veterinaria , Enfermedades de los Perros/virología , Mamastrovirus/aislamiento & purificación , Norovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Animales , Infecciones por Astroviridae/virología , Infecciones por Caliciviridae/virología , Perros , Mamastrovirus/genética , Datos de Secuencia Molecular , Norovirus/genética , Filogenia , Uruguay
6.
J Appl Microbiol ; 119(3): 859-67, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26010679

RESUMEN

AIMS: The aim of this study was to investigate the presence of the recently identified human astrovirus (HAstV) and to increase the knowledge of the molecular epidemiology of classical HAstV detected in Uruguay. METHODS AND RESULTS: Recently identified and classical HAstV genotypes were investigated by RT-PCR targeting the ORF1b and ORF2 genome regions in 20 samples obtained between September 2011 and April 2013 in two cities of the eastern region of Uruguay. Four of 20 samples (20%) were identified as MLB-1 genotype and it was found a new MLB-1 classification through the segregation of the worldwide reported MLB-1 strains in two genetic lineages proposed and named: MLB-1a and MLB-1b. Fourteen (70%) samples were positive for classical HAstV and 12 of them were successfully sequenced and genotyped as: HAstV-1 (n = 10), HAstV-2 and HAstV-5 (one sample each). CONCLUSION: These results constitute the first report in the Latin American region concerning the molecular detection and characterization of MLB-1 HAstV strains in environmental samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the benefits of an environmental surveillance to study emerging enteric viruses circulating in human societies.


Asunto(s)
Infecciones por Astroviridae/virología , Mamastrovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Secuencia de Bases , Monitoreo del Ambiente , Gastroenteritis/virología , Genotipo , Humanos , Mamastrovirus/clasificación , Mamastrovirus/genética , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Uruguay/epidemiología
7.
J Clin Pharm Ther ; 40(2): 135-43, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25475762

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Antiepileptic drugs often produce serious adverse effects, and many patients do not respond to them properly. Phytocannabinoids produce anticonvulsant effects in preclinical and preliminary human studies, and appear to produce fewer adverse effects than available antiepileptic drugs. The present review summarizes studies on the anticonvulsant properties of phytocannabinoids. METHODS: Literature search using the PubMed database to identify studies on phytocannabinoids and epilepsy. RESULTS AND DISCUSSION: Preclinical studies suggest that phytocannabinoids, especially cannabidiol and cannabidivarin, have potent anticonvulsant effects which are mediated by the endocannabinoid system. Human studies are limited in number and quality, but suggest that cannabidiol has anticonvulsant effects in adult and infantile epilepsy and is well tolerated after prolonged administration. WHAT IS NEW AND CONCLUSION: Phytocannabinoids produce anticonvulsant effects through the endocannabinoid system, with few adverse effects. Cannabidiol and cannabidivarin should be tested in randomized, controlled clinical trials, especially in infantile epileptic syndromes.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Cannabinoides/uso terapéutico , Epilepsia/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Animales , Cannabidiol/uso terapéutico , Corteza Cerebral/metabolismo , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Dronabinol/uso terapéutico , Evaluación Preclínica de Medicamentos , Endocannabinoides/biosíntesis , Humanos , Fitoterapia , Extractos Vegetales/química
8.
J Appl Microbiol ; 117(4): 1210-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24980661

RESUMEN

AIMS: This study was conducted to assess rotavirus A (RV-A), genogroup II (GII) norovirus (NoV), and human adenovirus (HAdV) dissemination in recreational water in an urban beach located in the city of Rio de Janeiro and their persistence during rainfall events. METHODS AND RESULTS: Viruses, including bacteriophage (PP7), used as internal control, were concentrated, reverse transcribed and quantified by a low-cost method based on organic flocculation with skimmed milk coupled with quantitative polymerase chain reaction protocols. The analysis of 74 superficial water samples obtained during 6 months of monitoring detected HAdV (66%), RV-A (37%) and GII NoV (14%), with a mean viral load of 4·1 log10 genome copies l(-1) (g.c. l(-1) ), 4·3 log10 g.c l(-1) and 3·8 log10 g.c. l(-1) , respectively. Investigation of those viruses during two rainfall events showed a longer permanence after rainfall events compared with bacterial indicators. CONCLUSIONS: The results highlight the need for further monitoring using viral parameters to determine the microbiological quality of recreational waters to allow bath in these waters, especially during rainy events. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides data on virus contamination in recreational waters on tourist beaches frequented throughout the year, emphasizing the importance of viral parameters for assessing microbiological quality of water, as well as the potential risk of waterborne infections.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Norovirus/aislamiento & purificación , Lluvia/virología , Rotavirus/aislamiento & purificación , Agua de Mar/virología , Virología/métodos , Adenovirus Humanos/genética , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Brasil , Ciudades , Gastroenteritis/virología , Humanos , Norovirus/genética , Rotavirus/genética
9.
Genet Mol Res ; 13(3): 6272-86, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25158254

RESUMEN

Abscisic acid-responsive element binding protein (AREB1) is a basic domain/leucine zipper transcription factor that binds to the abscisic acid (ABA)-responsive element motif in the promoter region of ABA-inducible genes. Because AREB1 is not sufficient to direct the expression of downstream genes under non-stress conditions, an activated form of AREB1 (AREB1ΔQT) was created. Several reports claim that plants overexpressing AREB1 or AREB1ΔQT show improved drought tolerance. In our studies, soybean plants overexpressing AREB1ΔQT were characterized molecularly, and the phenotype and drought response of three lines were accessed under greenhouse conditions. Under conditions of water deficit, the transformed plants presented a higher survival rate (100%) than those of their isoline, cultivar BR 16 (40%). Moreover, the transformed plants displayed better water use efficiency and had a higher number of leaves than their isoline. Because the transgenic plants had higher stomatal conductance than its isoline under well-watered conditions, it was suggested that the enhanced drought response of AREB1ΔQT soybean plants might not be associated with altered transpiration rates mediated by ABA-dependent stomatal closure. However, it is possible that the smaller leaf area of the transgenic plants reduced their transpiration and water use, causing delayed stress onset. The difference in the degree of wilting and percentage of survival between the 35S-AREB1ΔQT and wildtype plants may also be related to the regulation of genes that protect against dehydration because metabolic impairment of photosynthesis, deduced by an increasing internal CO2 concentration, was not observed in the transgenic plants.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Regulación de la Expresión Génica de las Plantas , Glycine max/genética , Hojas de la Planta/genética , Agua/metabolismo , Ácido Abscísico/metabolismo , Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Sequías , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Elementos de Respuesta , Glycine max/metabolismo , Transgenes
10.
Nat Prod Res ; : 1-6, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37367484

RESUMEN

In the present study, we have evaluated the cytotoxic activity of 282 extracts from 72 native plant species of the Brazilian Atlantic Forest biome. As a result, Casearia arborea and Sorocea hilarii leaves extracts showed cytotoxic activity against three tumour cell lines tested (B16F10, SW480 and Jurkat). After bioassay-guided fractionation, the bioactive fractions were submitted to the dereplication study via High-performance Liquid Chromatography, connected to High-resolution Mass Spectrometry (HPLC-ESI-QTOF/MS) analysis, combined with a Global Natural Products Social Molecular Networking (GNPS) tool. A combination of bioactivity-guided and dereplication approaches resulted in the putative annotation of 27 clerodane diterpenes and 9 flavonoids as main compounds present in the cytotoxic fractions of C. arborea. Regarding the active fraction of S. hilarii, 10 megastigmans, 17 spirostane steroids derivatives and 2 lignans were putatively identified. In conclusion, Casearia arborea and Sorocea hilarii are potential sources of antitumor compounds.

11.
J Med Virol ; 82(7): 1272-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20513095

RESUMEN

Group A rotaviruses (RV-A) are the major cause of gastroenteritis in infants and young children around the world. Each year RV-A causes approximately 11 million episodes of severe diarrhea, with an estimated of 611,000 deaths. Epidemiologic surveys have identified P[8]G1, P[4]G2, P[8]G3, P[8]G4, and P[8]G9 as the most common global genotypes associated with diarrhea in children up to 5-year old. Surveillance studies and documentation of RV-A G and P genotypes is necessary for a comprehensive evaluation of the evolution of new strains, and assessing the capability of vaccines to provide heterotypic protection. It is known that reassortments are the driving force for genetic diversity through sudden changes in RV-A genome. In this study, we identified two unusual P/G combinations, P[8]G8 and P[4]G8, occurring in Rio de Janeiro during 2002. Results obtained in this study suggest that P[8]G8 RV-A strain originated from a reassortment event that occurred between RV-A P[4]G8 and P[8]G9 strains circulating in Rio de Janeiro in the same year. G8 strains identified in this study, as well as G8 strains detected in Recife by Montenegro et al. [Montenegro et al. (2007) J Med Virol 79: 335-340], showed a close genetic relationship with strains from Africa, where this genotype have become prevalent.


Asunto(s)
Diarrea/epidemiología , Virus Reordenados/aislamiento & purificación , Infecciones por Rotavirus/epidemiología , Rotavirus/aislamiento & purificación , Brasil/epidemiología , Diarrea/virología , Humanos , Epidemiología Molecular , Filogenia , ARN Viral/genética , Virus Reordenados/clasificación , Virus Reordenados/genética , Rotavirus/clasificación , Rotavirus/genética , Infecciones por Rotavirus/virología , Población Urbana
12.
J Med Virol ; 82(8): 1442-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20572088

RESUMEN

A 4-year (2005-2008) norovirus (NoV) surveillance study was conducted in the state of Rio Janeiro, Brazil, to demonstrate the role of these viruses in outbreaks and sporadic cases of acute gastroenteritis. A cohort of 1,687 fecal samples was obtained from patients with gastroenteritis; 324 were rotavirus-positive. Of the remainder 1,363 rotavirus-negative samples, 1,087 samples were tested for NoV RNA in this study. The study enrolled 267 outpatients from Municipal Public Health Centers and 820 inpatients, whose samples were obtained by active surveillance in Public Hospitals. Fecal samples were tested by reverse transcription (RT) followed by polymerase chain reaction (PCR) using the MON 431-434 set of degenerate primers for NoV GI and GII detection, and there were 35.1% (381/1,087) positive samples for NoV, consisting of 30.2% (248/820) and 49.8% (133/267) from inpatient and outpatient, respectively. Children infected by NoV had significantly more frequent mucus in feces, vomiting and fever. No seasonal pattern in NoV infections was observed in patients admitted to hospital; however, two peaks of NoV infections were observed from ambulatory cases, suggesting that there was an occurrence of outbreaks in those time periods. Molecular characterization revealed GII to be the most prevalent genogroup, totaling 96.3% (104/108) of all sequences analyzed, and GII.4 was the genotype detected most frequently (80.7%), followed by GII.6, 3, 14, 7, and 8. Two GI strains, GI.2 and GI.3, were also observed. The number of outbreaks and sporadic cases described in this study highlights the need to implement diagnosis of NoV in surveillance laboratories.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Gastroenteritis/epidemiología , Norovirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Infecciones por Caliciviridae/patología , Infecciones por Caliciviridae/virología , Niño , Preescolar , Cartilla de ADN/genética , Brotes de Enfermedades , Heces/virología , Femenino , Gastroenteritis/patología , Gastroenteritis/virología , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Norovirus/clasificación , Norovirus/genética , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/aislamiento & purificación , Análisis de Secuencia de ADN , Adulto Joven
13.
J Appl Microbiol ; 109(1): 231-8, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20059621

RESUMEN

AIMS: To assess norovirus (NoV) contamination in aquatic ecosystems in the city of Florianópolis, in Southern Brazil, to provide epidemiological data that can support actions for environmental contamination control. METHODS AND RESULTS: An adsorption-elution method, followed by ultrafiltration, was performed to concentrate the viruses. NoV were detected using semi-nested PCR and quantified by real-time PCR. From June 2007 to May 2008, NoV were detected in 23% (22/94) of the samples analysed, including seawater, drinking water, superficial water (creek and brackish lagoon) and treated sewage. The mean viral loads for genogroups (G)I and GII in treated sewage samples were 297 and 440 genomic copies (gc) l(-1) , respectively, whereas creek water samples contained 2603 and 1361 gc l(-1) , respectively. Six samples were sequenced: two samples were GII.4, two were GII.2 and two were GI.3. CONCLUSIONS: NoV were detected in all water types analysed, demonstrating the widespread contamination of this geographical area with several cocirculating strains belonging to GI and GII. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the environmental spread of NoV in environmental waters and highlights the potential hazard for human health following the consumption of or contact with these waters, which could result in waterborne or foodborne acute gastroenteritis.


Asunto(s)
Monitoreo del Ambiente/métodos , Norovirus/aislamiento & purificación , Microbiología del Agua , Brasil , Ciudades , Agua Dulce/virología , Norovirus/genética , Filogenia , ARN Viral/aislamiento & purificación , Agua de Mar/virología , Análisis de Secuencia de ARN , Aguas del Alcantarillado/virología
14.
Braz J Microbiol ; 41(4): 1093-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24031592

RESUMEN

Canine parvovirus (CPV) is the most important enteric virus for dogs and it seems to be undergoing continuous evolution, generating new genetic and antigenic variants throughout the world. The aim of this study was to analyze the distribution of CPV variants from 1995 to 2009 and to investigate the circulation of the new variant CPV-2c in Rio de Janeiro, Brazil. In addition, the clinical features of CPV infection were also reported. After CPV laboratorial confirmation by HA/HI and PCR, thirty-two fecal samples were analyzed by sequencing a 583-bp fragment of the VP2 gene. One sample, collected in 2008 was typed as the new type CPV-2c. All samples from 1995 to 2003 were identified as "new CPV-2a". From 2004 to 2006, both "new CPV-2a" and CPV-2b were observed. From 2006 to 2009, most of the samples were characterized as CPV-2b. The classical signs of CPV enteritis were observed in 16/18 CPV-2a and 5/13 CPV-2b infected puppies. These results show that continuous epidemiological surveillance of CPV strain distribution is essential for studying the patterns of CPV-2a and 2b spread and for determining whether the new variant CPV-2c has become permanently established in Brazilian canine population.

15.
Water Sci Technol ; 60(3): 633-42, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19657158

RESUMEN

Rotaviruses A (RV-A) infection is the most common cause of acute diarrheal diseases in infants and the dissemination of these viruses in the environment represents a public health hazard. The present study aims to evaluate reverse transcription-polymerase chain reaction (RT-PCR) based protocols for the detection of RV-A genes in different types of environmental samples. RV-A were concentrated by the adsorption-elution method using negatively charged membranes associated with a Centriprep Concentrator 50. The RV-A VP4, VP7 and VP6 genes were detected using RT-PCR in river water from the Amazon Hydrographic basin (Northern region) and from wastewater in a sewage treatment plant in Rio de Janeiro (Southeast region), Brazil. RV-A were successfully detected in water environmental samples by the methods used. The detection of the VP6 gene by RT-PCR was the most sensitive for detecting RV-A in environmental samples (44.0%), when compared to the detection of the VP4 (33.3%) and VP7 (25.3%) genes. Based on nucleotide sequence and phylogenetic analysis of the partial VP6 gene, 22 environmental samples were determined to be subgroup II (Wa-like). These results indicate that analysis of environmental samples could possibly make a valuable contribution to studies on the epidemiology of RV-A.


Asunto(s)
Ambiente , Microbiología Ambiental , Rotavirus/clasificación , Rotavirus/aislamiento & purificación , Brasil , Genes Virales , Humanos , Filogenia , Rotavirus/genética , Serotipificación , Eliminación de Residuos Líquidos , Microbiología del Agua , Purificación del Agua
16.
Mem Inst Oswaldo Cruz ; 103(4): 326-31, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18660984

RESUMEN

The Epstein-Barr virus (EBV) is the etiological agent of oral hairy leukoplakia (OHL), an oral lesion with important diagnostic and prognostic value in acquired immunodeficiency disease syndrome. The two EBV genotypes, EBV-1 and EBV-2, can be distinguished by divergent gene sequences encoding the EBNA-2, 3A, 3B, and 3C proteins. The purpose of this study was to identify the EBV genotype prevalent in 53 samples of scrapings from the lateral border of the tongue of HIV-1 seropositive patients, with and without OHL, and to correlate the genotypes with presence of clinical or subclinical OHL with the clinic data collected. EBV-1 and EBV-2 were identified through PCR and Nested-PCR based on sequence differences of the EBNA-2 gene. EBV-1 was identified in the 31 samples (15 without OHL, 7 with clinical OHL and 9 with subclinical OHL), EBV-2 in 12 samples (10 without OHL, 1 with clinical and 1 subclinical OHL), and a mixed infection in 10 samples (2 without OHL, 3 with clinical and 5 with subclinical OHL). The presence of EBV-1 was higher in women, but a significant statistical result relating one the EBV genotypes to the development of OHL was not found. We conclude that the oral epithelium in HIV-1 seropositive patients can be infected by EBV-1, EBV-2 or by a mixed viral population.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/virología , VIH-1 , Herpesvirus Humano 4/genética , Leucoplasia Vellosa/virología , Lengua/virología , Adulto , Anciano , ADN Viral/genética , Electroforesis en Gel de Agar , Femenino , Genotipo , Herpesvirus Humano 4/clasificación , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
17.
Braz J Med Biol Res ; 50(4): e5670, 2017 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-28355354

RESUMEN

Regional cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) in young and elderly participants were assessed using pulsed arterial spin labeling (ASL) and blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) techniques in combination with inhalation of CO2. Pulsed ASL and BOLD-MRI were acquired in seventeen asymptomatic volunteers (10 young adults, age: 30±7 years; 7 elderly adults, age: 64±8 years) with no history of diabetes, hypertension, and neurological diseases. Data from one elderly participant was excluded due to the incorrigible head motion. Average baseline CBF in gray matter was significantly reduced in elderly (46±9 mL·100 g-1·min-1) compared to young adults (57±8 mL·100 g-1·min-1; P=0.02). Decreased pulsed ASL-CVR and BOLD-CVR in gray matter were also observed in elderly (2.12±1.30 and 0.13±0.06 %/mmHg, respectively) compared to young adults (3.28±1.43 and 0.28±0.11 %/mmHg, respectively; P<0.05), suggesting some degree of vascular impairment with aging. Moreover, age-related decrease in baseline CBF was observed in different brain regions (inferior, middle and superior frontal gyri; precentral and postcentral gyri; superior temporal gyrus; cingulate gyri; insula, putamen, caudate, and supramarginal gyrus). In conclusion, CBF and CVR were successfully investigated using a protocol that causes minimal or no discomfort for the participants. Age-related decreases in baseline CBF and CVR were observed in the cerebral cortex, which may be related to the vulnerability for neurological disorders in aging.


Asunto(s)
Envejecimiento/fisiología , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Dióxido de Carbono/metabolismo , Circulación Cerebrovascular/fisiología , Imagen por Resonancia Magnética/métodos , Marcadores de Spin , Adulto , Factores de Edad , Anciano , Análisis de Varianza , Mapeo Encefálico/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/metabolismo , Valores de Referencia , Estadísticas no Paramétricas , Factores de Tiempo , Adulto Joven
18.
Neuroscience ; 353: 87-97, 2017 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-28433649

RESUMEN

Brain glucose metabolism is altered in sporadic Alzheimer's disease (sAD), whose pathologies are reproduced in rodents by intracerebroventricular (icv) infusion of streptozotocin (STZ) in subdiabetogenic doses. The icv-STZ model also culminates in central cholinergic dysfunctions, which in turn are known to underlie both the sAD cognitive decline, and synaptic plasticity impairments. Considering the cognitive-enhancing potential of chronic nicotine (Nic), we investigated whether it attenuates icv-STZ-induced impairments in recognition memory and synaptic plasticity in a cognition-relevant substrate: the hippocampal CA1-medial prefrontal cortex (mPFC) pathway. Rats treated with icv-STZ were submitted to a chronic Nic regime, and were evaluated for recognition memory. We then examined long-term potentiation (LTP), paired-pulse facilitation (PPF) under urethane anesthesia, and brains were also evaluated for hippocampus-mPFC cell density. We found that Nic treatment prevents icv-STZ-induced disruptions in recognition memory and LTP. STZ did not precipitate neuronal death, while Nic alone was associated with higher neuronal density in CA1 when compared to vehicle-injected animals. Through combining behavioral, neurophysiological, and neuropathological observations into the Nic-STZ interplay, our study reinforces that cholinergic treatments are of clinical importance against early-stage Alzheimer's disease and mild cognitive impairments.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/psicología , Región CA1 Hipocampal/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Nicotina/administración & dosificación , Corteza Prefrontal/efectos de los fármacos , Reconocimiento en Psicología/efectos de los fármacos , Enfermedad de Alzheimer/inducido químicamente , Animales , Región CA1 Hipocampal/fisiología , Recuento de Células , Modelos Animales de Enfermedad , Locomoción/efectos de los fármacos , Masculino , Neuronas/efectos de los fármacos , Corteza Prefrontal/fisiología , Ratas Wistar , Reconocimiento en Psicología/fisiología , Estreptozocina , Potenciales Sinápticos/efectos de los fármacos
19.
Braz J Med Biol Res ; 39(1): 129-35, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16400473

RESUMEN

The clinical manifestations of neurocysticercosis (NC) are varied and depend on the number and location of cysts, as well as on the host immune response. Symptoms usually occur in NC when cysticerci enter a degenerative course associated with an inflammatory response. The expression of brain damage markers may be expected to increase during this phase. S100B is a calcium-binding protein produced and released predominantly by astrocytes that has been used as a marker of reactive gliosis and astrocytic death in many pathological conditions. The aim of the present study was to investigate the levels of S100B in patients in different phases of NC evolution. Cerebrospinal fluid and serum S100B concentrations were measured in 25 patients with NC: 14 patients with degenerative cysts (D), 8 patients with viable cysts (V) and 3 patients with inactive cysts. All NC patients, except 1, had five or less cysts. In most of them, symptoms had been present for at least 1 month before sample collection. Samples from 8 normal controls (C) were also assayed. The albumin quotient was used to estimate the blood-brain barrier permeability. There were no significant differences in serum (P = 0.5) or cerebrospinal fluid (P = 0.91) S100B levels among the V, D, and C groups. These findings suggest that parenchymal changes associated with a relatively small number of degenerating cysts probably have a negligible impact on glial tissue.


Asunto(s)
Factores de Crecimiento Nervioso/sangre , Factores de Crecimiento Nervioso/líquido cefalorraquídeo , Neurocisticercosis/sangre , Neurocisticercosis/líquido cefalorraquídeo , Proteínas S100/sangre , Proteínas S100/líquido cefalorraquídeo , Adolescente , Adulto , Anciano , Animales , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Subunidad beta de la Proteína de Unión al Calcio S100
20.
Braz J Med Biol Res ; 39(10): 1365-72, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16906314

RESUMEN

We describe the relative frequency, clinical features, neuroimaging and pathological results, and outcome after pharmacological or surgical intervention for a series of pediatric patients with temporal lobe epilepsy (TLE) from an epilepsy center in Brazil. The medical records of children younger than 12 years with features strongly suggestive of TLE were reviewed from January 1999 to June 1999. Selected children were evaluated regarding clinical, EEG, and magnetic resonance imaging (MRI) investigation and divided into three groups according to MRI: group 1 (G1, N = 9), patients with hippocampal atrophy; group 2 (G2, N = 10), patients with normal MRI, and group 3 (G3, N = 12), patients with other specific temporal lesions. A review of 1732 records of children with epilepsy revealed 31 cases with TLE (relative frequency of 1.79%). However, when the investigation was narrowed to cases with intractable seizures that needed video-EEG monitoring (N = 68) or epilepsy surgery (N = 32), the relative frequency of TLE increased to 19.11 (13/68) and 31.25% (10/32), respectively. At the beginning of the study, 25 of 31 patients had a high seizure frequency (80.6%), which declined to 11 of 31 (35.5%) at the conclusion of the study, as a consequence of pharmacological and/or surgical therapy. This improvement in seizure control was significant in G1 (P < 0.05) and G3 (P < 0.01) mainly due to good postsurgical outcome, and was not significant in G2 (P > 0.1, McNemar's test). These results indicate that the relative frequency of TLE in children was low, but increased considerably among cases with pharmacoresistant seizures. Patients with specific lesions were likely to undergo surgery, with good postoperative outcomes.


Asunto(s)
Epilepsia del Lóbulo Temporal/patología , Hipocampo/patología , Lóbulo Temporal/patología , Atrofia , Niño , Preescolar , Electroencefalografía/métodos , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Periodo Posoperatorio , Estudios Retrospectivos , Resultado del Tratamiento , Grabación en Video
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