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1.
Gen Hosp Psychiatry ; 81: 46-50, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36764261

RESUMO

OBJECTIVE: Predicting risk of posttraumatic stress disorder (PTSD) in the acute care setting is challenging given the pace and acute care demands in the emergency department (ED) and the infeasibility of using time-consuming assessments. Currently, no accurate brief screening for long-term PTSD risk is routinely used in the ED. One instrument widely used in the ED is the 27-item Immediate Stress Reaction Checklist (ISRC). The aim of this study was to develop a short screener using a machine learning approach and to investigate whether accurate PTSD prediction in the ED can be achieved with substantially fewer items than the IRSC. METHOD: This prospective longitudinal cohort study examined the development and validation of a brief screening instrument in two independent samples, a model development sample (N = 253) and an external validation sample (N = 93). We used a feature selection algorithm to identify a minimal subset of features of the ISRC and tested this subset in a predictive model to investigate if we can accurately predict long-term PTSD outcomes. RESULTS: We were able to identify a reduced subset of 5 highly predictive features of the ISRC in the model development sample (AUC = 0.80), and we were able to validate those findings in the external validation sample (AUC = 0.84) to discriminate non-remitting vs. resilient trajectories. CONCLUSION: This study developed and validated a brief 5-item screener in the ED setting, which may help to improve the diagnostic process of PTSD in the acute care setting and help ED clinicians plan follow-up care when patients are still in contact with the healthcare system. This could reduce the burden on patients and decrease the risk of chronic PTSD.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estudos Prospectivos , Estudos Longitudinais , Serviço Hospitalar de Emergência
2.
J Vet Cardiol ; 34: 48-54, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33561812

RESUMO

A 2-month-old male Holstein calf was presented for evaluation of a continuous systolic murmur. A grade V/VI left basilar continuous murmur and a grade IV/VI right basilar continuous murmur was auscultated upon evaluation with increased respiratory effort, wheezes, and crackles. Multimodality diagnostics were performed on this patient for further workup and included transthoracic and transesophageal echocardiography, fluoroscopy guided angiography, and gross necropsy with histopathology. An aortopulmonary window with continuous left-to-right shunting was identified at the level of the left aortic sinus of Valsalva with a severely dilated left coronary artery and left-sided congestive heart failure. This case report outlines the diagnostic workup of a rare congenital heart defect and secondary cardiac abnormalities not previously identified in veterinary literature.


Assuntos
Aneurisma , Cardiopatias Congênitas , Seio Aórtico , Aneurisma/veterinária , Animais , Valva Aórtica , Vasos Coronários , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/veterinária , Masculino , Imagem Multimodal
3.
AJNR Am J Neuroradiol ; 41(7): 1263-1268, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32661051

RESUMO

BACKGROUND AND PURPOSE: SWI is an advanced imaging modality that is especially useful in cerebral microhemorrhage detection. Such microhemorrhages have been identified in adult contact sport athletes, and the sequelae of these focal bleeds are thought to contribute to neurodegeneration. The purpose of this study was to utilize SWI to determine whether the prevalence and incidence of microhemorrhages in adolescent football players are significantly greater than those of adolescent noncontact athletes. MATERIALS AND METHODS: Preseason and postseason SWI was performed and evaluated on 78 adolescent football players. SWI was also performed on 27 adolescent athletes who reported no contact sport history. Two separate one-tailed Fisher exact tests were performed to determine whether the prevalence and incidence of microhemorrhages in adolescent football players are greater than those of noncontact athlete controls. RESULTS: Microhemorrhages were observed in 12 football players. No microhemorrhages were observed in any controls. Adolescent football players demonstrated a significantly greater prevalence of microhemorrhages than adolescent noncontact controls (P = .02). Although 2 football players developed new microhemorrhages during the season, microhemorrhage incidence during 1 football season was not statistically greater in the football population than in noncontact control athletes (P = .55). CONCLUSIONS: Adolescent football players have a greater prevalence of microhemorrhages compared with adolescent athletes who have never engaged in contact sports. While microhemorrhage incidence during 1 season is not significantly greater in adolescent football players compared to adolescent controls, there is a temporal association between playing football and the appearance of new microhemorrhages.


Assuntos
Hemorragia Cerebral Traumática/diagnóstico por imagem , Hemorragia Cerebral Traumática/etiologia , Futebol Americano/lesões , Neuroimagem/métodos , Adolescente , Atletas , Humanos , Incidência , Imageamento por Ressonância Magnética/métodos , Masculino , Prevalência
4.
Acta Psychiatr Scand ; 140(4): 360-370, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31355420

RESUMO

OBJECTIVE: Subthreshold perceptual abnormalities are commonly used to identify individuals at clinical high risk (CHR) for developing a psychotic disorder. Predictive validity for modality-specific perceptual abnormality severity on psychosis risk is unknown. METHODS: We examined prospectively collected data from 164 individuals age 12-35 meeting criteria for CHR followed for 6-24 months or until conversion to psychosis. Using intake interview notes, baseline perceptual abnormality scores were split into auditory, visual, somatic/tactile, and olfactory/gustatory components, and auditory scores were further split into those for verbal vs non-verbal content. Relationships between perceptual abnormality characteristics and conversion were assessed with Cox proportional hazards regression and logistic regression. RESULTS: Unusual thought content and paranoia were predictive of conversion, but no modality-specific perceptual abnormality score predicted conversion status or days to conversion. However, when auditory perceptual abnormalities were further categorized as verbal vs non-verbal, the severity of verbal experiences was predictive of conversion to psychosis (P = 0.007). CONCLUSIONS: Perceptual abnormality scores failed to meaningfully predict conversion to psychosis in either direction in this CHR sample. However, verbal auditory experiences may identify a group of CHR individuals at elevated risk of conversion. Further exploration of the relationship between phenomenological aspects of perceptual abnormalities and conversion risk is warranted.


Assuntos
Alucinações/psicologia , Percepção/fisiologia , Transtornos da Percepção/psicologia , Transtornos Psicóticos/psicologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Alucinações/complicações , Humanos , Masculino , Transtornos Paranoides/diagnóstico , Transtornos Paranoides/psicologia , Valor Preditivo dos Testes , Sintomas Prodrômicos , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/etnologia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Adulto Jovem
5.
J Med Entomol ; 55(3): 587-599, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29444287

RESUMO

Despite evidence of arbovirus activity in northwestern Uganda (West Nile Sub-region), there is very limited information on the mosquito fauna of this region. The only published study reported 52 mosquito species in northwestern Uganda but this study took place in 1950 and the information has not been updated for more than 60 yr. In January and June 2011, CO2 baited-light traps were used to collect 49,231 mosquitoes from four different locations, Paraa (9,487), Chobe (20,025), Sunguru (759), and Rhino Camp (18,960). Overall, 72 mosquito species representing 11 genera were collected. The largest number of distinct species was collected at Chobe (43 species), followed by Paraa (40), Sunguru (34), and Rhino Camp (25). Only eight of the 72 species (11.1%) were collected from all four sites: Aedes (Stegomyia) aegypti formosus (Walker), Anopheles (Cellia) funestus group, Culex (Culex) decens group, Cx. (Culex) neavei Theobald, Cx. (Culex) univittatus Theobald, Cx. (Culiciomyia) cinereus Theobald, Cx. (Oculeomyia) poicilipes (Theobald), and Mansonia (Mansonoides) uniformis (Theobald). Fifty-four species were detected in northwestern Uganda for the first time; however, these species have been detected elsewhere in Uganda and do not represent new introductions to the country. Thirty-three species collected during this study have previously been implicated in the transmission of arboviruses of public health importance.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Animais , Culicidae/classificação , Uganda
6.
Science ; 357(6351): 596-600, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28798131

RESUMO

Some people hear voices that others do not, but only some of those people seek treatment. Using a Pavlovian learning task, we induced conditioned hallucinations in four groups of people who differed orthogonally in their voice-hearing and treatment-seeking statuses. People who hear voices were significantly more susceptible to the effect. Using functional neuroimaging and computational modeling of perception, we identified processes that differentiated voice-hearers from non-voice-hearers and treatment-seekers from non-treatment-seekers and characterized a brain circuit that mediated the conditioned hallucinations. These data demonstrate the profound and sometimes pathological impact of top-down cognitive processes on perception and may represent an objective means to discern people with a need for treatment from those without.


Assuntos
Encéfalo/fisiologia , Condicionamento Clássico , Alucinações/psicologia , Percepção , Estimulação Acústica , Adulto , Simulação por Computador , Feminino , Alucinações/fisiopatologia , Audição , Humanos , Masculino , Modelos Neurológicos , Rede Nervosa , Neuroimagem , Estimulação Luminosa , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Voz
7.
J Clin Virol ; 74: 61-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26679829

RESUMO

BACKGROUND: Data regarding the viremia profile of chikungunya virus (CHIKV) infected patients especially during the pre-febrile period is limited. OBJECTIVE: To obtain virological kinetic data on CHIKV infections. STUDY DESIGN: A two-week community observation for dengue transmission was conducted in Bandung, Indonesia, from 2005 to 2009. Acute specimens from non-dengue febrile patients were screened by pan-alphavirus conventional RT-PCR. The positives were confirmed for CHIKV RNA by a specific RT-PCR followed by sequencing. Simultaneously these specimens were also cultured in Vero cells and tested for anti-CHIK IgM MAC-ELISA. All the available serial specimens,including the pre-febrile specimens, from confirmed CHIK cases, were tested by virus isolation, RT-PCR, qRT-PCR, and CHIK IgM ELISA. RESULTS: There were five laboratory confirmed CHIK cases identified and studied. Among these, viremia was determined to extend from as early as 6 days prior to until 13 days post fever onset. Quantitative RT-PCR showed viremia peaked at or near onset of illness. CONCLUSION: In this study, individuals were identified with viremia prior to fever onset and extending beyond the febrile phase. This extended viremic phase has the potential to impact transmission dynamics and thus the public health response to CHIK outbreaks.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Carga Viral , Viremia/diagnóstico , Adolescente , Adulto , Anticorpos Antivirais/sangue , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina M/sangue , Indonésia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
8.
Oncogene ; 35(15): 1996-2002, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26119930

RESUMO

Germline BAP1 mutations predispose to several cancers, in particular malignant mesothelioma. Mesothelioma is an aggressive malignancy generally associated with professional exposure to asbestos. However, to date, we found that none of the mesothelioma patients carrying germline BAP1 mutations were professionally exposed to asbestos. We hypothesized that germline BAP1 mutations might influence the asbestos-induced inflammatory response that is linked to asbestos carcinogenesis, thereby increasing the risk of developing mesothelioma after minimal exposure. Using a BAP1(+/-) mouse model, we found that, compared with their wild-type littermates, BAP1(+/-) mice exposed to low-dose asbestos fibers showed significant alterations of the peritoneal inflammatory response, including significantly higher levels of pro-tumorigenic alternatively polarized M2 macrophages, and lower levels of several chemokines and cytokines. Consistent with these data, BAP1(+/-) mice had a significantly higher incidence of mesothelioma after exposure to very low doses of asbestos, doses that rarely induced mesothelioma in wild-type mice. Our findings suggest that minimal exposure to carcinogenic fibers may significantly increase the risk of malignant mesothelioma in genetically predisposed individuals carrying germline BAP1 mutations, possibly via alterations of the inflammatory response.


Assuntos
Asbesto Crocidolita/toxicidade , Mesotelioma/etiologia , Neoplasias Peritoneais/etiologia , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Animais , Asbesto Crocidolita/administração & dosagem , Líquido Ascítico/química , Quimiocinas/análise , Citocinas/análise , Relação Dose-Resposta a Droga , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Heterozigoto , Leucócitos/patologia , Macrófagos Peritoneais/classificação , Macrófagos Peritoneais/fisiologia , Masculino , Mesotelioma/genética , Camundongos , Camundongos Endogâmicos C57BL , Fibras Minerais/toxicidade , Neoplasias Peritoneais/genética , Peritonite/etiologia , Peritonite/genética , Distribuição Aleatória , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/fisiologia , Ubiquitina Tiolesterase/deficiência , Ubiquitina Tiolesterase/fisiologia
9.
Cell Death Dis ; 6: e1786, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26068794

RESUMO

High-mobility group box 1 (HMGB1) is an inflammatory molecule that has a critical role in the initiation and progression of malignant mesothelioma (MM). Aspirin (acetylsalicylic acid, ASA) is the most widely used nonsteroidal anti-inflammatory drug that reduces the incidence, metastatic potential and mortality of many inflammation-induced cancers. We hypothesized that ASA may exert anticancer properties in MM by abrogating the carcinogenic effects of HMGB1. Using HMGB1-secreting and -non-secreting human MM cell lines, we determined whether aspirin inhibited the hallmarks of HMGB1-induced MM cell growth in vitro and in vivo. Our data demonstrated that ASA and its metabolite, salicylic acid (SA), inhibit motility, migration, invasion and anchorage-independent colony formation of MM cells via a novel HMGB1-mediated mechanism. ASA/SA, at serum concentrations comparable to those achieved in humans taking therapeutic doses of aspirin, and BoxA, a specific inhibitor of HMGB1, markedly reduced MM growth in xenograft mice and significantly improved survival of treated animals. The effects of ASA and BoxA were cyclooxygenase-2 independent and were not additive, consistent with both acting via inhibition of HMGB1 activity. Our findings provide a rationale for the well documented, yet poorly understood antitumorigenic activity of aspirin, which we show proceeds via HMGB1 inhibition. Moreover, the use of BoxA appears to allow a more efficient HMGB1 targeting while eluding the known gastrointestinal side effects of ASA. Our findings are directly relevant to MM. Given the emerging importance of HMGB1 and its tumor-promoting functions in many cancer types, and of aspirin in cancer prevention and therapy, our investigation is poised to provide broadly applicable information.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Proteína HMGB1/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Ácido Salicílico/uso terapêutico , Células 3T3 , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Proteína HMGB1/metabolismo , Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Mesotelioma Maligno , Camundongos , Camundongos Knockout , Camundongos SCID , Invasividade Neoplásica/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Med Entomol ; 49(6): 1289-306, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23270157

RESUMO

The mosquito fauna in many areas of western Uganda has never been studied and is currently unknown. One area, Bwamba County, has been previously studied and documented but the species lists have not been updated for >40 yr. This paucity of data makes it difficult to determine which arthropod-borne viruses pose a risk to human or animal populations. Using CO2 baited-light traps, from 2008 through 2010, 67,731 mosquitoes were captured at five locations in western Uganda including Mweya, Sempaya, Maramagambo, Bwindi (BINP), and Kibale (KNP). Overall, 88 mosquito species, 7 subspecies, and 7 species groups in 10 genera were collected. The largest number of species was collected at Sempaya (65 species), followed by Maramagambo (45), Mweya (34), BINP (33), and KNP (22). However, species diversity was highest in BINP (Simpson's Diversity Index 1-D = 0.85), followed by KNP (0.80), Maramagambo (0.79), Sempaya (0.67), and Mweya (0.56). Only six species Aedes (Aedimorphus) cumminsii (Theobald), Aedes (Neomelaniconion) circumluteolus (Theobald), Culex (Culex) antennatus (Becker), Culex (Culex) decens group, Culex (Lutzia) tigripes De Grandpre and De Charmoy, and Culex (Oculeomyia) annulioris (Theobald), were collected from all five sites suggesting large differences in species composition among sites. Four species (Aedes (Stegomyia) metallicus (Edwards), Anopheles (Cellia) rivulorum Leeson, Uranotaenia (Uranotaenia) chorleyi (Edwards), and Uranotaenia (Uranotaenia) pallidocephala (Theobald) and one subspecies (Aedes (Stegomyia) aegypti formosus (Walker)) were collected in Bwamba County for the first time. This study represents the first description of the mosquito species composition of Mweya, Maramagambo, BINP, and KNP. A number of morphological variations were noted regarding the postspiracular scales, hind tibia, and sternites that make Culex (Culex) neavei (Theobald) challenging to identify. At least 50 species collected in this study have previously been implicated in the transmission of arboviruses of public health importance suggesting a high potential for maintenance and transmission of a wide variety of arboviruses in western Uganda.


Assuntos
Biodiversidade , Culicidae , Animais , Insetos Vetores , Uganda
12.
Diabetologia ; 55(3): 707-18, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22167125

RESUMO

AIMS/HYPOTHESIS: Our understanding of the transcription factors that control the development and function of rodent islet beta cells is advancing rapidly, yet less is known of the role they play in similar processes in human islets. METHODS: To characterise the abundance and regulation of key proteins involved in glucose-regulated insulin secretion in human islets, we examined the expression of MAFA, MAFB, GLUT2 (also known as SLC2A2), ßGK (also known as GCK) and PDX1 in isolated, highly purified human islets with an intact insulin secretory pattern. We also assessed these features in islets from two different mouse strains (C57BL/6J and FVB). RESULTS: Compared with mouse islets, human islets secreted more insulin at baseline glucose (5.6 mmol/l), but less upon stimulation with high glucose (16.7 mmol/l) or high glucose plus 3-isobutyl-1-methyl-xanthine. Human islets had relatively more MAFB than PDX1 mRNA, while mouse islets had relatively more Pdx1 than Mafb mRNA. However, v-maf musculoaponeurotic fibrosarcoma oncogene homologue (MAF) B protein was found in human islet alpha and beta cells. This is unusual as this regulator is only produced in islet alpha cells in adult mice. The expression of insulin, MAFA, ßGK and PDX1 was not glucose-regulated in human islets with an intact insulin secretory pattern. CONCLUSIONS/INTERPRETATION: Our results suggest that human islets have a distinctive distribution and function of key regulators of the glucose-stimulated insulin secretion pathway, emphasising the urgent need to understand the processes that regulate human islet beta cell function.


Assuntos
Regulação da Expressão Gênica , Hiperglicemia/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Via Secretória , Adolescente , Adulto , Animais , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Fator de Transcrição MafB/genética , Fator de Transcrição MafB/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Pessoa de Meia-Idade , Inibidores de Fosfodiesterase/farmacologia , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/metabolismo , Via Secretória/efeitos dos fármacos , Especificidade da Espécie , Técnicas de Cultura de Tecidos , Transativadores/genética , Transativadores/metabolismo , Adulto Jovem
13.
Diabetologia ; 54(8): 2152-63, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21519965

RESUMO

AIMS/HYPOTHESIS: Aldosterone concentrations increase in obesity and predict the onset of diabetes. We investigated the effects of aldosterone on glucose homeostasis and insulin secretion in vivo and in vitro. METHODS: We assessed insulin sensitivity and insulin secretion in aldosterone synthase-deficient (As [also known as Cyp11b2](-/-)) and wild-type mice using euglycaemic-hyperinsulinaemic and hyperglycaemic clamps, respectively. We also conducted studies during high sodium intake to normalise renin activity and potassium concentration in As (-/-) mice. We subsequently assessed the effect of aldosterone on insulin secretion in vitro in the presence or absence of mineralocorticoid receptor antagonists in isolated C57BL/6J islets and in the MIN6 beta cell line. RESULTS: Fasting glucose concentrations were reduced in As (-/-) mice compared with wild-type. During hyperglycaemic clamps, insulin and C-peptide concentrations increased to a greater extent in As (-/-) than in wild-type mice. This was not attributable to differences in potassium or angiotensin II, as glucose-stimulated insulin secretion was enhanced in As (-/-) mice even during high sodium intake. There was no difference in insulin sensitivity between As (-/-) and wild-type mice in euglycaemic-hyperinsulinaemic clamp studies. In islet and MIN6 beta cell studies, aldosterone inhibited glucose- and isobutylmethylxanthine-stimulated insulin secretion, an effect that was not blocked by mineralocorticoid receptor antagonism, but was prevented by the superoxide dismutase mimetic tempol. CONCLUSIONS/INTERPRETATION: We demonstrated that aldosterone deficiency or excess modulates insulin secretion in vivo and in vitro via reactive oxygen species and in a manner that is independent of mineralocorticoid receptors. These findings provide insight into the mechanism of glucose intolerance in conditions of relative aldosterone excess.


Assuntos
Aldosterona/metabolismo , Aldosterona/farmacologia , Glucose/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Citocromo P-450 CYP11B2/deficiência , Citocromo P-450 CYP11B2/genética , Técnicas In Vitro , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Methods Mol Biol ; 665: 17-38, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21116793

RESUMO

Alphaviruses remain important emerging mosquito-borne, zoonotic pathogens that cause both localized human outbreaks and epizootics (e.g., Venezuelan equine encephalitis) and large human epidemics (e.g., Chikungunya). Alphaviruses are globally dispersed, and each continent has humans at risk from one or more of these arthropod-borne viruses (arboviruses). Symptoms of human alphaviral disease range from frank, severe encephalitis (e.g., eastern and western equine encephalitis) to polyarthritis (e.g., Ross River). Diagnostic techniques to identify human alphaviral infections have changed dramatically with the development and implementation of standardized nucleic acid amplification tests (NAAT). The NAAT is rapidly replacing virus isolation and typing using indirect fluorescent antibody (IFA) assay with monoclonal antibodies (MAbs) as the preferred method of virus identification. The older techniques still have value, however, since alphaviral growth in cell culture is rapid, and IFA with MAbs is inexpensive. This chapter provides detailed, standardized protocols for the identification of alphaviruses from clinical specimens and the serological characterization of human infection-immune sera. Both laboratory approaches are needed to identify and confirm human infections with these agents.


Assuntos
Infecções por Alphavirus/virologia , Alphavirus/imunologia , Alphavirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Técnicas de Amplificação de Ácido Nucleico , Infecções por Alphavirus/diagnóstico , Animais , Anticorpos Monoclonais , Antígenos Virais/análise , Culicidae/virologia , Técnica Indireta de Fluorescência para Anticorpo/métodos , Humanos , Soros Imunes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
15.
J Med Entomol ; 45(6): 1187-90, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19058647

RESUMO

A new strain of Culex flavivirus (family Flaviviridae, genus Flavivirus, CxFV), an insect virus first described in Japan, was isolated from adult Culex quinquefasciatus Say (Diptera: Culicidae) collected in 2006 from Izabal Department on the Caribbean coast of Guatemala. Mosquito pools were assayed for flavivirus RNA by using flavivirus group-specific primers that amplified a 720-bp region of the nonstructural (NS) 5 gene by standard reverse transcriptase-polymerase chain reaction. From 210 pools (1,699 mosquitoes), eight tested positive, and six of these mosquito pools produced virus isolates in Aedes albopictus Skuse C6/36 cells. Nucleotide sequence comparison of the eight flavivirus RNA-positive pools showed that there was 100% identity among them, and phylogenetic analysis of the NS5 and envelope gene regions indicated that they represent a strain of the recently described CxFV from Japan. This is the first report of an insect flavivirus from Central America.


Assuntos
Culex/virologia , Flavivirus/isolamento & purificação , Animais , Feminino , Flavivirus/genética , Guatemala , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Alinhamento de Sequência , Proteínas do Envelope Viral/genética , Proteínas não Estruturais Virais/genética
16.
J Gen Virol ; 89(Pt 11): 2754-2760, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931072

RESUMO

The largest documented outbreak of Chikungunya virus (CHIKV) disease occurred in the Indian Ocean islands and India during 2004-2007. The magnitude of this outbreak led to speculation that a new variant of the virus had emerged that was either more virulent or more easily transmitted by mosquito vectors. To study this assertion, it is important to know the origin of the virus and how the particular strain circulating during the outbreak is related to other known strains. This study genetically characterized isolates of CHIKV obtained from Mombasa and Lamu Island, Kenya, during 2004, as well as strains from the 2005 outbreak recorded in Comoros. The results of these analyses demonstrated that the virus responsible for the epidemic that spread through the Indian Ocean originated in coastal Kenya during 2004 and that the closest known ancestors are members of the Central/East African clade. Genetic elements that may be responsible for the scope of the outbreak were also identified.


Assuntos
Infecções por Alphavirus/epidemiologia , Vírus Chikungunya , África Oriental/epidemiologia , Animais , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Chlorocebus aethiops , Comores/epidemiologia , Primers do DNA , Amplificação de Genes , Genoma Viral , Humanos , Quênia/epidemiologia , Rim , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Células Vero
17.
Insect Mol Biol ; 13(6): 625-35, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15606811

RESUMO

Arthropod-borne alphaviruses transmitted by mosquitoes almost exclusively use culicines; however, the alphavirus o'nyong-nyong (ONNV) has the unusual characteristic of being transmitted primarily by anopheline mosquitoes. This unusual attribute makes ONNV a valuable tool in the characterization of mosquito determinants of infection as well as a useful expression system in Anopheles species. We developed a series of recombinant alphaviruses, based upon the genome of ONNV, designed for the expression of heterologous genes. The backbone genome is a full-length infectious cDNA clone of ONNV from which wild-type virus can be rescued. Additional constructs are variants of the primary clone and contain the complete genome plus a duplicated subgenomic promoter element with a multiple cloning site for insertion of heterologous genes. We inserted a green fluorescent protein (GFP) gene downstream of this promoter and used it to characterize infection and dissemination patterns of ONNV within An. gambiae mosquitoes. These experiments allowed us to identify atypical sites of initial infection and dissemination patterns in this mosquito species not frequently observed in comparable culicine infections. The utility of these ONNVs for studies in anopheline mosquitoes includes the potential for identification of vector infection determinants and to serve as tools for antimalaria studies. Viruses that can express a heterologous gene in a vector and rapidly and efficiently infect numerous tissues in An. gambiae mosquitoes will be a valuable asset in parasite-mosquito interaction and interference research.


Assuntos
Alphavirus/genética , Anopheles/virologia , Vetores Genéticos/genética , Animais , Células Cultivadas , DNA Complementar/genética , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Arch Virol Suppl ; (18): 43-64, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15119762

RESUMO

Following a period of inactivity from 1973-1991, Venezuelan equine encephalitis (VEE) reemerged during the past decade in South America and Mexico. Experimental studies of VEE virus (VEEV) infection of horses with virus strains isolated during these outbreaks have revealed considerable variation in the ability of equine-virulent, epizootic strains to exploit horses as efficient amplification hosts. Subtype IC strains from recent outbreaks in Venezuela and Colombia amplify efficiently in equines, with a correlation between maximum viremia titers and the extent of the outbreak from which the virus strain was isolated. Studies of enzootic VEEV strains that are believed to represent progenitors of the epizootic subtypes support the hypothesis that adaptation to efficient replication in equines is a major determinant of emergence and the ability of VEEV to spread geographically. Correlations between the ability of enzootic and epizootic VEEV strains to infect abundant, equiphilic mosquitoes, and the location and extent of these outbreaks, also suggest that specific adaptation to Ochlerotatus taeniorhynchus mosquitoes is a determinant of some but not all emergence events. Genetic studies imply that mutations in the E2 envelope glycoprotein gene are major determinants of adaptation to both equines and mosquito vectors.


Assuntos
Encefalomielite Equina Venezuelana/transmissão , Animais , Modelos Animais de Doenças , Vetores de Doenças , Vírus da Encefalite Equina Venezuelana/classificação , Vírus da Encefalite Equina Venezuelana/genética , Vírus da Encefalite Equina Venezuelana/patogenicidade , Cavalos , Humanos , Zoonoses
19.
Gene Ther ; 10(19): 1712-20, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12923570

RESUMO

Glucagon-like peptide 1 (GLP-1) is released from neuroendocrine cells in the intestine in the postprandial state and augments glucose-stimulated insulin secretion from pancreatic beta cells. To develop non-beta cells that exhibit physiologically regulated insulin secretion, we coexpressed the GLP-1 receptor and human insulin in primary rat pituitary cells using adenovirus-mediated gene transfer. The transduced cells were analyzed in a perifusion system and after transplantation into mice. Normal pituitary cells do not express the GLP-1 receptor as shown by the absence of GLP-1 receptor mRNA and the inability of GLP-1 to stimulate pituitary hormone secretion. Following transduction with an adenovirus carrying the GLP-1 receptor cDNA, the pituitary cells expressed functional GLP-1 receptors as reflected by the ability of GLP-1 to stimulate secretion of pituitary hormones. When both the GLP-1 receptor and human insulin were introduced, GLP-1 stimulated cosecretion of human insulin and endogenous pituitary hormones. GLP-1 was similar in potency to the hypothalamic-releasing hormones and stimulated hormone secretion in a dose-dependent fashion. In contrast to pancreatic beta cells, the hormone-releasing effect of GLP-1 on transduced pituitary cells was not dependent on the concentration of extracellular glucose. After transplantation of pituitary cells coexpressing human insulin and GLP-1 receptor into mice, enteral glucose stimulated insulin secretion. These results demonstrate a new approach to engineer physiologically regulated insulin secretion by non-beta cells.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Terapia Genética/métodos , Insulina/genética , Insulina/metabolismo , Hipófise/metabolismo , Receptores de Glucagon/genética , Adenoviridae/genética , Animais , Células Cultivadas , Diabetes Mellitus Tipo 1/metabolismo , Expressão Gênica , Vetores Genéticos/administração & dosagem , Receptor do Peptídeo Semelhante ao Glucagon 1 , Glucose/farmacologia , Humanos , Secreção de Insulina , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Hipófise/efeitos dos fármacos , Hormônios Hipofisários/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Glucagon/análise , Estimulação Química , Transdução Genética/métodos
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