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1.
PLoS One ; 17(3): e0265037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35302988

RESUMO

Grazing patterns, intake structure, and diet selection are dynamic responses to animals' feeding environment. This study uses video sequences from animal-borne cameras to capture time- and scale-dependent grazing behaviour variables related to sward explanatory conditions. We observed grazing 'through' the sheep's eyes using point-of-view (POV) cameras coupled with event logging software. Time-specific sward features were measured by sampling 'really' grazed patches identified by applying a global navigation satellite system (GNSS) precision-grazing approach. Sward variables on a Mediterranean native sward were measured for two years during the active spring plant-growth cycle. Overall, the results demonstrate that POV cameras were able to capture grazing behaviour fine-tuning to changes in sward characteristics. Sheep compensate for the decrease in sward quantity and nutritive value by increasing the size and duration at each behavioural scale (i.e., meal, bout, and station) while increasing the bout rate and decreasing the station rate. Diet composition also changed as sward matured. The proportion of forbs in the diet remained high in early and late spring, and forbs and legumes were preferred to grasses in early spring. Grazing selectivity was more pronounced in late spring, with sheep favouring the middle stratum of the sward's vertical structure, preferring green vegetative material, while enlarging the feeding niches' span and spending more time at each niche, consequently reducing the station rate. Although data collected by individual animal-borne POV cameras were representative of the flock behaviour, they may underestimate the total grazing time outside major meals. The results indicate that the use of animal-borne video cameras is suitable for assessing variations in sheep grazing behaviour patterns in complex swards.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Dieta/veterinária , Comportamento Alimentar/fisiologia , Valor Nutritivo , Poaceae , Ovinos
2.
Arch Microbiol ; 200(6): 961-970, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29616305

RESUMO

Influenza viruses cause worldwide outbreaks and pandemics in humans and animals every year with considerable morbidity and mortality. The molecular diversity of secondary metabolites extracted from mollusks is a good alternative for the discovery of novel bioactive compounds with unique structures and diverse biological activities. Phyllocaulis boraceiensis is a hermaphroditic slug that exudes mucus, in which was detected hydroxy polyunsaturated fatty acids that exhibited potent antiviral activity against measles virus. The objective of this study was to evaluate this property against Influenza viruses. Cell viability and toxicity of the mucus were evaluated on Madin-Darby canine kidney (MDCK) cells by MTT assay. Antiviral activity from mucus against influenza viruses was carried out by determination of the virus infection dose and by immunofluorescence assays. The crude mucus and its fractions exhibited low cytotoxicity on MDCK cells. A significant inhibition of viral replication, reduced by the order of eight times, was observed in influenza-induced cytopathic effect. In immunofluorescence assay was observed a decrease of more than 80% of the viral load on infected MDCK cell treated with mucus and its fractions. The viral glycoproteins hemagglutinin and neuraminidase located on the surface of the virus are crucial for the replications and infectivity of the influenza virus. Some authors demonstrated that lipids, such as, polyunsaturated fatty acids exhibited multiple roles in antiviral innate and adaptive responses, control of inflammation, and in the development of antiviral therapeutics. As corroborated by other studies, hydroxy polyunsaturated fatty acids interfered with the binding of influenza virus on host cell receptor and reduced viral titers. The results obtained indicated that polyunsaturated fatty acids from P. boraceiensis crude mucus and fractions 39 exerted antiviral activity against influenza virus.


Assuntos
Antivirais/farmacologia , Ácidos Graxos Insaturados/farmacologia , Gastrópodes/química , Muco/química , Orthomyxoviridae/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/metabolismo , Cães , Ácidos Graxos Insaturados/metabolismo , Gastrópodes/metabolismo , Humanos , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Muco/metabolismo , Orthomyxoviridae/fisiologia
3.
Arch Virol ; 163(5): 1325-1330, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29392492

RESUMO

The aims of this study were to investigate the human bocavirus (HBoV) frequency and genotypes in hospitalized children <5 years presenting acute respiratory infections (ARI) within the São Paulo metropolitan area. Nasopharyngeal samples from 300 patients, previously screened for common respiratory viruses, were tested by qPCR for the NSP1 and NP-1 genes. The VP1/2 gene in positive samples was then amplified by PCR and sequenced. A total of 49 positive HBoV cases (16.3%; mean Ct value of 34.41) were detected with the mean age being 18.1 months (range 1 month to 5 years) and the median age being 1 year of age. Children aged between 0 and 12 months had higher detection rates of HBoV (69.4%; 34/49; mean Ct = 34.45) than children from other age groups (30.6%; 15/49; mean Ct = 34.34). No significant differences were observed between HBoV Ct levels and clinical illness. The occurrence was more frequently associated with fall (38.8%; 19/49) and spring (36.7%; 18/49). All 12 sequenced isolates were identified as HBoV-1, displaying minor genetic variation compared to the Swedish reference strains ST1 and ST2 (99.1-99.7% nt). The sole identification of HBoV-1 supports the hypothesis that this particular genotype is strongly related to ARI, and contributes to the role of this virus in the aetiology of respiratory diseases.


Assuntos
Bocavirus Humano/genética , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Infecções Respiratórias/virologia , Doença Aguda/epidemiologia , Brasil/epidemiologia , Criança , Pré-Escolar , DNA Viral/genética , Monitoramento Epidemiológico , Feminino , Variação Genética , Genótipo , Bocavirus Humano/fisiologia , Humanos , Lactente , Masculino , Nasofaringe/virologia , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Virais/genética
4.
Arch. Microbiol. ; 200(6): p. 961-970, 2018.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15242

RESUMO

Influenza viruses cause worldwide outbreaks and pandemics in humans and animals every year with considerable morbidity and mortality. The molecular diversity of secondary metabolites extracted from mollusks is a good alternative for the discovery of novel bioactive compounds with unique structures and diverse biological activities. Phyllocaulis boraceiensis is a hermaphroditic slug that exudes mucus, in which was detected hydroxy polyunsaturated fatty acids that exhibited potent antiviral activity against measles virus. The objective of this study was to evaluate this property against Influenza viruses. Cell viability and toxicity of the mucus were evaluated on Madin-Darby canine kidney (MDCK) cells by MTT assay. Antiviral activity from mucus against influenza viruses was carried out by determination of the virus infection dose and by immunofluorescence assays. The crude mucus and its fractions exhibited low cytotoxicity on MDCK cells. A significant inhibition of viral replication, reduced by the order of eight times, was observed in influenza-induced cytopathic effect. In immunofluorescence assay was observed a decrease of more than 80% of the viral load on infected MDCK cell treated with mucus and its fractions. The viral glycoproteins hemagglutinin and neuraminidase located on the surface of the virus are crucial for the replications and infectivity of the influenza virus. Some authors demonstrated that lipids, such as, polyunsaturated fatty acids exhibited multiple roles in antiviral innate and adaptive responses, control of inflammation, and in the development of antiviral therapeutics. As corroborated by other studies, hydroxy polyunsaturated fatty acids interfered with the binding of influenza virus on host cell receptor and reduced viral titers. The results obtained indicated that polyunsaturated fatty acids from P. boraceiensis crude mucus and fractions 39 exerted antiviral activity against influenza virus.

5.
Arch Microbiol, v. 200, n. 6, p. 961-970, ago. 2018
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2497

RESUMO

Influenza viruses cause worldwide outbreaks and pandemics in humans and animals every year with considerable morbidity and mortality. The molecular diversity of secondary metabolites extracted from mollusks is a good alternative for the discovery of novel bioactive compounds with unique structures and diverse biological activities. Phyllocaulis boraceiensis is a hermaphroditic slug that exudes mucus, in which was detected hydroxy polyunsaturated fatty acids that exhibited potent antiviral activity against measles virus. The objective of this study was to evaluate this property against Influenza viruses. Cell viability and toxicity of the mucus were evaluated on Madin-Darby canine kidney (MDCK) cells by MTT assay. Antiviral activity from mucus against influenza viruses was carried out by determination of the virus infection dose and by immunofluorescence assays. The crude mucus and its fractions exhibited low cytotoxicity on MDCK cells. A significant inhibition of viral replication, reduced by the order of eight times, was observed in influenza-induced cytopathic effect. In immunofluorescence assay was observed a decrease of more than 80% of the viral load on infected MDCK cell treated with mucus and its fractions. The viral glycoproteins hemagglutinin and neuraminidase located on the surface of the virus are crucial for the replications and infectivity of the influenza virus. Some authors demonstrated that lipids, such as, polyunsaturated fatty acids exhibited multiple roles in antiviral innate and adaptive responses, control of inflammation, and in the development of antiviral therapeutics. As corroborated by other studies, hydroxy polyunsaturated fatty acids interfered with the binding of influenza virus on host cell receptor and reduced viral titers. The results obtained indicated that polyunsaturated fatty acids from P. boraceiensis crude mucus and fractions 39 exerted antiviral activity against influenza virus.

6.
Artigo em Inglês | MEDLINE | ID: mdl-25861357

RESUMO

The studies on chemical composition and biological activity of propolis had focused mainly on species Apis mellifera L. (Hymenoptera: Apidae). There are few studies about the uncommon propolis collected by stingless bees of the Meliponini tribe known as geopropolis. The geopropolis from Scaptotrigona postica was collected in the region of Barra do Corda, Maranhão state, Brazil. The chemical analysis of hydromethanolic extract of this geopropolis (HMG) was carried out through HPLC-DAD-ESI-MS/MS and the main constituents found were pyrrolizidine alkaloids and C-glycosyl flavones. The presence of alkaloids in extracts of propolis is detected for the first time in this sample. The antiviral activity of HMG was evaluated through viral DNA quantification experiments and electron microscopy experiments. Quantification of viral DNA from herpes virus showed reduction of about 98% in all conditions and concentration tested of the HMG extract. The results obtained were corroborated by transmission electron microscopy, in which the images did not show particle or viral replication complex. The antiviral activity of C-glycosyl flavones was reported for a variety of viruses, being observed at different points in the viral replication. This work is the first report about the antiviral activity of geopropolis from Scaptotrigona postica, in vitro, against antiherpes simplex virus (HSV).

7.
Cytotechnology ; 67(6): 1011-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24908059

RESUMO

This study presents a new recombinant protein that acts as a powerful antiviral (rAVLO-recombinant Antiviral protein of Lonomia obliqua). It was able to reduce the replication by 10(6) fold for herpes virus and by 10(4) fold for rubella virus. RT-PCR of viral RNA rAVLO treated infected cells also showed similar rate of inhibition in replication. The analysis of this protein by bioinformatics suggests that this protein is globular, secreted with a signal peptide and has the ability to bind to MHC class I. It was found that there are several protein binding sites with various HLA and a prevalence of α-helices in the N-terminal region (overall classified as a α/ß protein type). BLAST similarity sequence search for corresponding cDNA did not reveal a similar sequence in Genbank, suggesting that it is from a novel protein family. In this study we have observed that this recombinant protein and hemolymph has a potent antiviral action. This protein was produced in a baculovirus/Sf-9 system. Therefore, these analyses suggest that this novel polypeptide is a candidate as a broad spectrum antiviral.

9.
Arch Virol ; 159(6): 1445-51, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24327091

RESUMO

The aim of the present study was to identify the rubella virus (RV) and enterovirus (EV) genotypes detected during the Epidemiological Surveillance on Exanthematic Febrile Diseases (VIGIFEX) study and to perform phylogenetic analysis. Ten RV- and four EV-positive oropharyngeal samples isolated from cell culture were subjected to RT-PCR and sequencing. Genotype 1G and echovirus 9 (E-9) was identified in RV- and EV-positive samples, respectively. The RV 1G genotype has been persisting in Brazil since 2000-2001. No evidence of E-9 being involved in exanthematic illness in Brazil has been reported previously. Differential laboratory diagnosis is essential for management of rash and fever disease.


Assuntos
Echovirus 9/isolamento & purificação , Infecções por Echovirus/epidemiologia , Vírus da Rubéola/isolamento & purificação , Rubéola (Sarampo Alemão)/epidemiologia , Brasil/epidemiologia , Análise por Conglomerados , Echovirus 9/classificação , Echovirus 9/genética , Infecções por Echovirus/virologia , Genótipo , Epidemiologia Molecular , Dados de Sequência Molecular , Orofaringe/virologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rubéola (Sarampo Alemão)/virologia , Vírus da Rubéola/classificação , Vírus da Rubéola/genética , Análise de Sequência de DNA
10.
J Clin Virol ; 58(4): 737-40, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24216323

RESUMO

Involvement of the central nervous system is common in measles, but rare in rubella. However, rubella virus (RV) can cause a variety of central nervous system syndromes, including meningitis, encephalitis, Guillain-Barré syndrome and sub acute sclerosing panencephalitis. We report the occurrence of one fatal case of the encephalitis associated with measles-rubella (MR) vaccine during an immunization campaign in São Paulo, Brazil. A 31 year-old-man, previously in good health, was admitted at emergency room, with confusion, agitation, inability to stand and hold his head up. Ten days prior to admission, he was vaccinated with combined MR vaccine (Serum Institute of India) and three days later he developed 'flu-like' illness with fever, myalgia and headache. Results of clinical and laboratory exams were consistent with a pattern of viral encephalitis. During hospitalization, his condition deteriorated rapidly with tetraplegia and progression to coma. On the 3rd day of hospitalization he died. Histopathology confirmed encephalitis and immunohistochemistry was positive for RV on brain tissue. RV was also detected by qPCR and virus isolation in cerebrospinal fluid, brain and other clinical samples. The sequence obtained from the isolated virus was identical to that of the RA 27/3 vaccine strain.


Assuntos
Encefalite/virologia , Vacina contra Rubéola/efeitos adversos , Vírus da Rubéola/genética , Rubéola (Sarampo Alemão)/virologia , Adulto , Encéfalo/virologia , Evolução Fatal , Humanos , Masculino , Vírus da Rubéola/classificação , Vírus da Rubéola/isolamento & purificação
11.
J Med Virol ; 85(11): 2034-41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23861141

RESUMO

Rubella virus (RV) infection during the early stages of pregnancy can lead to serious birth defects, known as congenital rubella syndrome (CRS). This retrospective study was conducted between 1996 and 2009 with surveillance specimens collected from patients suspected of congenital rubella infection (CRI) and CRS. The clinical samples (nine amminiotic fluid, eight urine, eight blood, one conception product, and one placenta) were sent for viral isolation and genotyping. Twenty-seven sequences were analysed and four genotypes (1a, 1B, 1G, and 2B) were identified in São Paulo that were involved in congenital infection. To our knowledge, this study is the first report that describes genetic diversity of the circulating rubella strains involved in CRI.


Assuntos
Variação Genética , Síndrome da Rubéola Congênita/epidemiologia , Síndrome da Rubéola Congênita/virologia , Vírus da Rubéola/classificação , Vírus da Rubéola/genética , Adulto , Brasil/epidemiologia , Análise por Conglomerados , Feminino , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Gravidez , RNA Viral/genética , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus da Rubéola/isolamento & purificação , Análise de Sequência de DNA , Adulto Jovem
13.
Pediatr Infect Dis J ; 29(6): 573-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20228694

RESUMO

Acute liver failure is a syndrome with a wide range of etiologic possibilities in children, but in up to 50% of the cases in the literature no diagnosis is established. This case report adds rubella virus to the list of possible causes of acute liver failure. This association was made by serologic, cell culture, molecular, histopathologic, and immunohistochemical methods.


Assuntos
Falência Hepática Aguda/virologia , Vírus da Rubéola/isolamento & purificação , Rubéola (Sarampo Alemão)/complicações , Animais , Pré-Escolar , Chlorocebus aethiops , Humanos , Falência Hepática Aguda/complicações , Falência Hepática Aguda/cirurgia , Transplante de Fígado , Masculino , RNA Viral/análise , Rubéola (Sarampo Alemão)/diagnóstico , Rubéola (Sarampo Alemão)/virologia , Vírus da Rubéola/genética , Células Vero , Proteínas do Envelope Viral/genética
14.
J Clin Virol ; 35(3): 285-91, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16310405

RESUMO

Sixty pregnant women with clinical signs of rubella and specific rubella antibodies were studied between January 1999 and December 2002 in order to determine the intrauterine rubella transmission rate and the presence of the virus in amniotic fluid and fetal tissues by nested PCR. Thirty-three patients presented rubella before 12 weeks of gestation and 27 after 12 weeks. Gestational age at the time of acute rubella was determined on the basis of the date of last menstruation and the first trimester ultrasound scan. Thirteen patients with clinical features of rubella before 12 weeks of gestation were submitted to amniocentesis. Three products of conception were analyzed. The presence of the rubella virus was determined by nested PCR. IgM and IgG antibodies were analyzed in neonatal samples at birth and at 3 months of age using a capture immunoassay. Newborn follow-up was based on the presence of congenital rubella syndrome-compatible defects, anti-rubella antibodies, echocardiographic alterations, brainstem evoked response audiometry, and ophthalmological pathology. Five miscarriages and four fetal deaths were observed in the group of patients presenting clinical features before 12 weeks of gestation. IgM antibodies were detected in seven neonates at birth and at 3 months of age. Deafness was observed in three cases and pigmentary retinopathy in one case. Fourteen of the 16 samples (13 amniotic fluid and 3 fetal tissue samples) submitted to virological analysis tested positive. Four fetal deaths, five miscarriages (one with negative virology) and seven newborns with anti-rubella IgM at birth and/or at 3 months age were observed in the group with rubella before 12 weeks of gestation. There were three cases in which virological analysis of the amniotic fluid samples was positive (infected) while the newborn showed no signs of congenital rubella syndrome and anti-rubella IgM were absent. When maternal rubella occurred after 12 weeks of gestation, no fetal or neonatal rubella signs were observed. Eradication of congenital rubella syndrome is possible since vaccination campaigns continue and all services related to the health care of children, adolescents and women have become aware of the significance of the problem and are collaborating. All pregnant women in Brazil should be screened for the rubella antibody and the susceptible group should be vaccinated after giving birth.


Assuntos
Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Rubéola (Sarampo Alemão)/transmissão , Adolescente , Adulto , Líquido Amniótico/virologia , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Surdez/etiologia , Feminino , Morte Fetal/etiologia , Feto/virologia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , RNA Viral/análise , Retinose Pigmentar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rubéola (Sarampo Alemão)/diagnóstico , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/patologia , Rubéola (Sarampo Alemão)/virologia , Síndrome da Rubéola Congênita/diagnóstico , Vírus da Rubéola/imunologia , Vírus da Rubéola/isolamento & purificação , Fatores de Tempo
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