RESUMO
Chagas disease, a potentially life-threatening disease caused by the protozoan parasite Trypanosoma cruzi, has become a concern in the United States as a result of human emigration from Latin America where Chagas disease is endemic (1). It is estimated that as many as 8 million people living in Mexico, and Central and South America have Chagas disease.* Most cases of Chagas disease in the United States are chronic infections; however, rare cases of acute congenital infections and autochthonous vectorborne transmission have been reported (2). To understand how data are collected and used, a review of state-level public health surveillance for Chagas disease was conducted through semistructured interviews with health officials in six states (Arizona, Arkansas, Louisiana, Mississippi Tennessee, and Texas) where Chagas disease is reportable and one (Massachusetts) where it was previously reportable. States implemented surveillance in response to blood donor screening for Chagas disease and to identify the route of disease transmission. Many states reported primarily chronic cases and had limited ability to respond to local transmission because acute cases were infrequently reported. Surveillance remains important in states with large populations of immigrants or frequent travelers from countries with endemic disease and for states with a risk for local transmission. Surveillance efforts can also help increase awareness among providers and assist in linking patients with Chagas disease to treatment to help prevent cardiac and gastrointestinal complications.
Assuntos
Doença de Chagas/epidemiologia , Emigrantes e Imigrantes , Vigilância da População , Emigração e Imigração/estatística & dados numéricos , Doenças Endêmicas , Humanos , América Latina/epidemiologia , América Latina/etnologia , Trypanosoma cruzi/isolamento & purificação , Estados Unidos/epidemiologiaRESUMO
: Estimates of the distribution and prevalence of the sinus roundworm ( Skrjabingylus chitwoodorum) have been based largely on the inspection of skunk (Mephitidae) skulls showing damage from infections. We examined 595 striped skunks ( Mephitis mephitis) and nine hog-nosed skunks ( Conepatus leuconotus) that had tested negative for rabies by the Texas Department of State Health Services (US) between November 2010 and April 2015 to determine species of Skrjabingylus, prevalence and intensity of infection, and distribution of infection in Texas by county. We expected ecoregions with more precipitation to have higher rates of infection than more-arid ecoregions. Prevalence of S. chitwoodorum in striped skunks was 48.7%, with a mean intensity of 19.4 (SD=24.44, range=1-181) nematodes. There was a bias for the left sinus. The prevalence of infection varied among ecoregions of Texas, but it was not correlated with precipitation. Infection intensity did not vary among ecoregions. The prevalence of sinus roundworms in rabies-negative skunks suggested that behavioral changes because of skrjabingylosis might have been responsible for the submission by the public of some skunks for rabies testing.
Assuntos
Mephitidae , Metastrongyloidea/isolamento & purificação , Seios Paranasais/parasitologia , Infecções por Strongylida/veterinária , Animais , Animais Selvagens , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/parasitologia , Texas/epidemiologiaRESUMO
In contrast to other mammalian reservoirs, many bat species migrate long-distances and have the potential to introduce exotic pathogens to new areas. Bats have long been associated with blood-borne protozoal trypanosomes of the Schizotrypanum subgenus, which includes the zoonotic parasite Trypanosoma cruzi, agent of Chagas disease. Another member of the subgenus, Trypanosoma dionisii, infects bats of Europe and South America, and genetic similarities between strains from the two continents suggest transcontinental movement of this parasite via bats. Despite the known presence of diverse trypanosomes in bats of Central and South America, and the presence of T. cruzi-infected vectors and wildlife in the US, the role of bats in maintaining and dispersing trypanosomes in the US has not yet been reported. We collected hearts and blood from 8 species of insectivorous bats from 30 counties across Texas. Using PCR and DNA sequencing, we tested 593 bats for trypanosomes and found 1 bat positive for T. cruzi (0.17%), 9 for T. dionisii (1.5%), and 5 for Blastocrithidia spp. (0.8%), a group of insect trypanosomes. The T. cruzi-infected bat was carrying TcI, the strain type associated with human disease in the US. In the T. dionisii-infected bats, we detected three unique variants associated with the three infected bat species. These findings represent the first report of T. cruzi in a bat in the US, of T. dionisii in North America, and of Blastocrithidia spp. in mammals, and underscore the importance of bats in the maintenance of trypanosomes, including agents of human and animal disease, across broad geographic locales.
Assuntos
Doença de Chagas/transmissão , Quirópteros/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Doença de Chagas/parasitologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Humanos , Filogenia , Análise de Sequência de DNA , Texas/epidemiologia , Trypanosoma cruzi/genéticaRESUMO
The south-central skunk rabies virus (SCSK) is the most broadly distributed terrestrial viral lineage in North America. Skunk rabies has not been efficiently targeted by oral vaccination campaigns and represents a natural system of pathogen invasion, yielding insights to rabies emergence. In the present study we reconstructed spatiotemporal spread of SCSK in the whole territory of its circulation using a combination of Bayesian methods. The analysis based on 241 glycoprotein gene sequences demonstrated that SCSK is much more divergent phylogenetically than was appreciated previously. According to our analyses the SCSK originated in the territory of Texas ~170 years ago, and spread geographically during the following decades. The wavefront velocity in the northward direction was significantly greater than in the eastward and westward directions. Rivers (except the Mississippi River and Rio Grande River) did not constitute significant barriers for epizootic spread, in contrast to deserts and mountains. The mean dispersal rate of skunk rabies was lower than that of the raccoon and fox rabies. Viral lineages circulate in their areas with limited evidence of geographic spread during decades. However, spatiotemporal reconstruction shows that after a long period of stability the dispersal rate and wavefront velocity of SCSK are increasing. Our results indicate that there is a need to develop control measures for SCSK, and suggest how such measure can be implemented most efficiently. Our approach can be extrapolated to other rabies reservoirs and used as a tool for investigation of epizootic patterns and planning interventions towards disease elimination.
Assuntos
Mephitidae/virologia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Animais , Glicoproteínas/genética , Filogeografia , Proteínas Virais/genéticaRESUMO
OBJECTIVE: To obtain epidemiological information on rabies in bats in Texas. DESIGN: Epidemiological study. SAMPLE: Laboratory reports of bats that had been submitted for rabies testing in Texas from 2001 through 2010. PROCEDURES: Laboratory reports were reviewed to obtain information on seasonality of rabies in bats; distribution, species, and rabies virus variants of rabid bats; and human and domestic animal exposures to rabid bats. RESULTS: The number of rabid bats during the first 5 years of the study period remained static until a > 2-fold increase in 2006; during the subsequent 4 years, the annual number of rabid bats remained at this higher level, including a peak in 2008. The highest proportions of rabid bats were seen in late summer and early fall. The Brazilian free-tailed bat (Tadarida brasiliensis) was the most often affected species. Additionally, the rabies virus variant associated with the Brazilian free-tailed bat was the most prevalent. The percentage of rabid bats from urban areas was greater than that from rural areas. Dogs and cats were the domestic animals most frequently exposed to rabid bats. Most humans exposed to rabid bats did not report a known bite or scratch. The highest numbers of humans exposed to rabid bats were males between 11 to 15 years old. CONCLUSIONS AND CLINICAL RELEVANCE: Information on the epidemiology of rabies in bats and the epidemiology of exposures to rabid bats may be useful in planning and implementing local, state, and national rabies control and prevention campaigns and in encouraging rabies vaccination of domestic animals.
Assuntos
Quirópteros , Raiva/veterinária , Adolescente , Adulto , Animais , Humanos , Masculino , Raiva/epidemiologia , Especificidade da Espécie , Texas/epidemiologia , Fatores de Tempo , ZoonosesRESUMO
AIM: Both hyperbaric oxygenation (HBO) and inhibition of the c-Jun N-terminal kinases (JNKs) by the peptide inhibitor XG-102 (D-JNKI-1) are efficient protective strategies against ischaemia-induced neurodegeneration. The present study investigated whether the combination of HBO and JNK inhibitor, XG-102, provides additive neuroprotection against cerebral ischaemia. METHODS: Rat middle cerebral artery was occluded (MCAO) for 90 min. XG-102 [2 mg/kg, intraperitoneally] or HBO (3 ATA, 60 min) was applied 3 h after the onset of MCAO. For the combination treatment, HBO was started 10 min after the injection of XG-102. Twenty-four hours after MCAO, the infarct area, the neurological score and the immunohistochemistry staining in brain slices for cleaved-PARP, transferase-mediated biotinylated UTP nick end labelling, c-Jun and phosphorylated (activated) c-Jun were observed. RESULTS: XG-102 or HBO alone reduced the total infarct area by 43% and 63%, respectively. The combination diminished total infarct area by 78%, improved the neurological function and reduced brain oedema. Co-application of HBO and XG-102 also significantly reduced the cleavage of PARP, by 96% and 91% in cortical penumbra and ischaemic core, respectively. Moreover, cotreatment significantly attenuated the number of cells labelled with transferase-mediated biotinylated UTP nick end labelling and phosphorylated c-Jun. CONCLUSION: Our study demonstrates that HBO reinforces the efficiency of neuroprotective drugs such as XG-102 and vice versa. Both treatments, physical HBO and pharmacological XG-102, are already in phase I/II studies and promising strategies for clinical use.
Assuntos
Inibidores Enzimáticos/uso terapêutico , Oxigenoterapia Hiperbárica/métodos , Infarto da Artéria Cerebral Média/terapia , Peptídeos/uso terapêutico , Envelhecimento , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/patologia , Edema Encefálico/terapia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Isquemia Encefálica/terapia , Inibidores Enzimáticos/administração & dosagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/administração & dosagem , Fosforilação , Proteínas Proto-Oncogênicas c-jun/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
AIMS/HYPOTHESIS: In insulin-secreting cells, activation of the c-Jun NH(2)-terminal kinase (JNK) pathway triggers apoptosis. Whereas JNK1 and JNK2 are ubiquitously produced, JNK3 has been described exclusively in neurons. This report aims to characterise the expression and role in apoptosis of the three JNK isoforms in insulin-secreting cells exposed to cytokines. METHODS: Sections of human and mouse pancreases were used for immunohistochemistry studies with isoform-specific anti-JNK antibodies. Human, pig, mouse and rat pancreatic islets were isolated by enzymatic digestion and RNA or protein extracts were prepared. RNA and protein levels were determined by quantitative RT-PCR and western blotting respectively, using JNK-isoform-specific primers and isoform-specific antibodies; activities of the three JNK isoforms were determined by kinase assays following quantitative immunoprecipitation/depletion of JNK3. JNK silencing was performed with small interfering RNAs and apoptotic rates were determined in INS-1E cells by scoring cells displaying pycnotic nuclei. RESULTS: JNK3 and JNK2 mRNAs are the predominant isoforms expressed in human pancreatic islets. JNK3 is nuclear while JNK2 is also cytoplasmic. In INS-1E cells, JNK3 knockdown increases c-Jun levels and caspase-3 cleavage and sensitises cells to cytokine-induced apoptosis; in contrast, JNK1 or JNK2 knockdown is protective. CONCLUSIONS/INTERPRETATION: In insulin-secreting cells, JNK3 plays an active role in preserving pancreatic beta cell mass from cytokine attacks. The specific localisation of JNK3 in the nucleus, its recruitment by cytokines, and its effects on key transcription factors such as c-Jun, indicate that JNK3 is certainly an important player in the transcriptional control of genes expressed in insulin-secreting cells.
Assuntos
Apoptose/efeitos dos fármacos , Citocinas/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Animais , Primers do DNA , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Pâncreas/citologia , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , Ratos , Ratos Wistar , Suínos , Doadores de Tecidos , Veias UmbilicaisRESUMO
The c-Jun N-terminal kinase (JNK) is a mitogen-activated protein kinase (MAPK) activated by stress-signals and involved in many different diseases. Previous results proved the powerful effect of the cell permeable peptide inhibitor d-JNKI1 (d-retro-inverso form of c-Jun N-terminal kinase-inhibitor) against neuronal death in CNS diseases, but the precise features of this neuroprotection remain unclear. We here performed cell-free and in vitro experiments for a deeper characterization of d-JNKI1 features in physiological conditions. This peptide works by preventing JNK interaction with its c-Jun N-terminal kinase-binding domain (JBD) dependent targets. We here focused on the two JNK upstream MAPKKs, mitogen-activated protein kinase kinase 4 (MKK4) and mitogen-activated protein kinase kinase 7 (MKK7), because they contain a JBD homology domain. We proved that d-JNKI1 prevents MKK4 and MKK7 activity in cell-free and in vitro experiments: these MAPKK could be considered not only activators but also substrates of JNK. This means that d-JNKI1 can interrupt downstream but also upstream events along the JNK cascade, highlighting a new remarkable feature of this peptide. We also showed the lack of any direct effect of the peptide on p38, MEK1, and extracellular signal-regulated kinase (ERK) in cell free, while in rat primary cortical neurons JNK inhibition activates the MEK1-ERK-Ets1/c-Fos cascade. JNK inhibition induces a compensatory effect and leads to ERK activation via MEK1, resulting in an activation of the survival pathway-(MEK1/ERK) as a consequence of the death pathway-(JNK) inhibition. This study should hold as an important step to clarify the strong neuroprotective effect of d-JNKI1.
Assuntos
Córtex Cerebral/citologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase 7/metabolismo , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Fator 2 Ativador da Transcrição/metabolismo , Sequência de Aminoácidos , Análise de Variância , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular , L-Lactato Desidrogenase/metabolismo , Peptídeos/farmacologia , Fosforilação , Ligação Proteica/fisiologia , Domínios e Motivos de Interação entre Proteínas , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteínas Elk-1 do Domínio ets/metabolismoRESUMO
The c-Jun-N-terminal kinase (JNK) pathway has been shown to play an important role in excitotoxic neuronal death and several studies have demonstrated a neuroprotective effect of D-JNKi, a peptide inhibitor of JNK, in various models of cerebral ischemia. We have now investigated the effect of D-JNKi in a model of transient focal cerebral ischemia (90 min) induced by middle cerebral artery occlusion (MCAo) in adult male rats. D-JNKi (0.1 mg/kg), significantly decreased the volume of infarct, 3 days after cerebral ischemia. Sensorimotor and cognitive deficits were then evaluated over a period of 6 or 10 days after ischemia and infarct volumes were measured after behavioral testing. In behavioral studies, D-JNKi improved the general state of the animals as demonstrated by the attenuation of body weight loss and improvement in neurological score, as compared with animals receiving the vehicle. Moreover, D-JNKi decreased sensorimotor deficits in the adhesive removal test and improved cognitive function in the object recognition test. In contrast, D-JNKi did not significantly affect the infarct volume at day 6 and at day 10. This study shows that D-JNKi can improve functional recovery after transient focal cerebral ischemia in the rat and therefore supports the use of this molecule as a potential therapy for stroke.
Assuntos
Inibidores Enzimáticos/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , Peptídeos/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal , Infarto Cerebral/etiologia , Infarto Cerebral/prevenção & controle , Circulação Cerebrovascular/efeitos dos fármacos , Modelos Animais de Doenças , Maleato de Dizocilpina/uso terapêutico , Lateralidade Funcional , Ataque Isquêmico Transitório/complicações , Masculino , Exame Neurológico/métodos , Fármacos Neuroprotetores/uso terapêutico , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reconhecimento Psicológico/efeitos dos fármacosRESUMO
BACKGROUND: We previously reported high prevalence of hepatitis C virus genotype 5a (HCV 5) (14%) in Central France. AIM: To identify the risk factors associated with HCV5 infection and to characterize local HCV5 lineages. METHOD: A case-control study and phylogenetic analysis were conducted. RESULTS: In all, 131 HCV5 and 343 HCV non 5 infected patients were enrolled. No HCV5 patient was born in sub-Saharan Africa and only two were injection drug user. HCV5 contamination was associated with living in a rural area called Vic le Comte (VLC) in non-transfused patients (OR = 17.7), with transfusion in patients living outside VLC (OR = 3.8) and with receiving injections in patients from VLC (OR = 3.1). More than 80% of the patients from outside VLC were contaminated by transfusion and those from VLC mainly by an iatrogenic factor - injections performed before 1972 by the local physician. Phylogenetic analysis of HCV5 isolates evidenced no distinct genetic cluster, but close relationships between the isolates of spouse pairs and between blood donors and recipients. CONCLUSIONS: Our results suggest that HCV5 spread in our district by iatrogenic route before 1972 and then via transfusion to the whole district. Collaborative studies are underway to study viral sequences from different parts of Africa and Europe to estimate the origin of our HCV 5a strains.
Assuntos
Hepacivirus/metabolismo , Hepatite C/virologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , França/epidemiologia , Genótipo , Hepatite C/epidemiologia , Hepatite C/transmissão , Anticorpos Anti-Hepatite C/análise , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de RiscoRESUMO
The c-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in ischemic brain injury. The d-retro-inverso form of c-Jun N-terminal kinase-inhibitor (D-JNKI1), a cell-permeable inhibitor of JNK, powerfully reduces neuronal death induced by permanent and transient ischemia, even when administered 6 h after the ischemic insult, offering a clinically relevant window. We investigated the JNK molecular cascade activation in rat cerebral ischemia and the effects of D-JNKI1 on this cascade. c-Jun activation starts after 3 h after ischemia and peaks at 6 h in the ischemic core and in the penumbra at 1 h and at 6 h respectively. The 6 h c-Jun activation peak correlates well with that of P-JNK. We also examined the activation of the two direct JNK activators, MAP kinase kinase 4 (MKK4) and MAP kinase kinase 7 (MKK7). MKK4 showed the same time course as JNK in both core and penumbra, reaching peak activation at 6 h. MKK7 did not show any significant increase of phosphorylation in either core or penumbra. D-JNKI1 markedly prevented the increase of P-c-Jun in both core and penumbra and powerfully inhibited caspase-3 activation in the core. These results confirm that targeting the JNK cascade using the TAT cell-penetrating peptide offers a promising therapeutic approach for ischemia, raising hopes for human neuroprotection, and elucidates the molecular pathways leading to and following JNK activation.
Assuntos
Caspase 3/metabolismo , Infarto da Artéria Cerebral Média/enzimologia , Infarto da Artéria Cerebral Média/prevenção & controle , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Peptídeos/administração & dosagem , Proteínas Proto-Oncogênicas c-jun/metabolismo , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
AIMS/HYPOTHESIS: The protocols used for the preparation of human pancreatic islets immediately induce a sustained and massive activation of the c-Jun-N-terminal kinase (JNK). JNK, which participates in apoptosis of insulin-secreting cells, is activated by mechanical stresses, as well as by exposure to pro-inflammatory cytokines. Here, we investigated whether the delivery of a protease-resistant JNK inhibitory peptide (D-JNKI) through a protein transduction system during pancreatic digestion might impair JNK signalling throughout the transplantation procedure. METHODS: Rat pancreases were treated with D-JNKI through the pancreatic duct and cells then isolated by enzymatic digestion. Protein extracts were prepared to determine JNK activity by kinase assays and total RNA was extracted to measure gene expressions by a Light-Cycler technique. Cell apoptosis rate was determined by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay and by scoring cells displaying pycnotic nuclei. RESULTS: Our data establish that the peptide transduction system used here efficiently transfects islets, allowing for stable in vivo (up to 2 days) transfection of human islets transplanted under the kidney capsule. Further, D-JNKI decreases intracellular JNK signalling during isolation and following cytokine exposure in both human and rat islets, as measured by kinase assays and reduced c-fos expression; D-JNKI also confers protection against apoptosis induced during the rat islet preparation and subsequent to IL-1beta exposure. CONCLUSIONS/INTERPRETATION: JNK signalling participates in islet isolation- and IL-1beta-induced apoptosis in rat islets. Furthermore, the system we used might be more generally applicable for the persistent blockage (several days) of pro-apoptotic pathways in the transplanted islets; this days-long protection might potentially be an absolute prerequisite to help transplanted islets better survive the first wave of the non-specific inflammatory attack.
Assuntos
Apoptose/efeitos dos fármacos , Citocinas/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Animais , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Marcação In Situ das Extremidades Cortadas , Interleucina-1beta/farmacologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/química , Masculino , Microscopia Confocal , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Excitotoxic insults induce c-Jun N-terminal kinase (JNK) activation, which leads to neuronal death and contributes to many neurological conditions such as cerebral ischemia and neurodegenerative disorders. The action of JNK can be inhibited by the D-retro-inverso form of JNK inhibitor peptide (D-JNKI1), which totally prevents death induced by N-methyl-D-aspartate (NMDA) in vitro and strongly protects against different in vivo paradigms of excitotoxicity. To obtain optimal neuroprotection, it is imperative to elucidate the prosurvival action of D-JNKI1 and the death pathways that it inhibits. In cortical neuronal cultures, we first investigate the pathways by which NMDA induces JNK activation and show a rapid and selective phosphorylation of mitogen-activated protein kinase kinase 7 (MKK7), whereas the only other known JNK activator, mitogen-activated protein kinase kinase 4 (MKK4), was unaffected. We then analyze the action of D-JNKI1 on four JNK targets containing a JNK-binding domain: MAPK-activating death domain-containing protein/differentially expressed in normal and neoplastic cells (MADD/DENN), MKK7, MKK4 and JNK-interacting protein-1 (IB1/JIP-1).
Assuntos
Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , N-Metilaspartato/toxicidade , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Neurotoxinas/toxicidade , Proteínas Adaptadoras de Transdução de Sinal/isolamento & purificação , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Cálcio/metabolismo , Córtex Cerebral/enzimologia , Cicloeximida/farmacologia , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte , Eletroforese em Gel Bidimensional , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Imunofluorescência , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase 7/metabolismo , Neurônios/citologia , Neurônios/patologia , Fosforilação/efeitos dos fármacos , Proteômica , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
We compared sustained virological response (SVR) in chronic hepatitis C patients with severe fibrosis treated with pegylated interferon (Peg-IFN) alpha-2b 1.5 microg/kg/week or 0.75 microg/kg/week in combination with ribavirin 800 mg/day for 48 weeks. This was a multicentre randomized controlled study. SVR was observed in 44.5% (45/101) of patients treated with the standard dose of Peg-IFN and 37.2% (38/102) of patients treated with the low dose (NS). In patients with genotypes 1, 4 and 5, SVR was observed in 25.0% of patients who received the standard dose and 16.9% of patients who received the low dose of Peg-IFN (P = NS). In patients with genotypes 1, 4 and 5 and low viraemia, SVR was obtained in 27.3% of patients treated with the standard dose and 25.8% of patients treated with the low dose (P = NS). In the high-viraemia subgroup, SVR was obtained in 24.0% and 9.1% of patients, respectively. In patients with genotypes 2 and 3, SVR was similar in both groups (73.2%vs 73.0%). Thus, (1) patients with genotypes 2 and 3 and severe fibrosis can be treated with low dose of Peg-IFN and ribavirin, (2) this study suggests that patients with genotypes 1, 4 and 5 and high viraemia could receive a standard dose of Peg-IFN associated with ribavirin for 48 weeks, (3) side effects limit the efficacy of the treatment with standard dose of Peg-IFN in patients with genotypes 1, 4 and 5 and low viraemia, (4) more studies are needed for patients with genotype 2 or 3 to define the optimal duration (24 or 48 weeks) in patients with severe fibrosis.
Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Idoso , Antivirais/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Polietilenoglicóis , Proteínas Recombinantes , Ribavirina/efeitos adversosRESUMO
AIM: To assess the rate of sustained virological response in naïve hepatitis C virus-type 5 patients treated by standard interferon or pegylated-interferon [corrected] (peg-interferon) and ribavirin combination for 48 weeks. PATIENTS AND METHODS: A total of 87 hepatitis C virus patients were included from 12 centres in France; 28 patients received interferon plus ribavirin and 59 were treated with peg-interferon plus ribavirin. RESULTS: Baseline characteristics were: mean age 58 +/- 11 years, sex ratio 1, 66% had metavir fibrosis score >or=F2, 21% were cirrhotics and 53% had pretherapeutic viral load >or=800,000 IU/mL. Sustained virological response was achieved in 64% and 58% of hepatitis C virus-5 patients treated with interferon and peg-interferon, respectively (NS). In adherent patients, sustained virological response was obtained in 75% of patients. Sustained virological response in hepatitis C virus-5 patients (60%) was significantly higher than sustained virological response in hepatitis C virus-1 patients (37%) (P = 0.0499) and not significantly different from sustained virological response in hepatitis C virus-2-3 patients (63%) (P = 0.8098). CONCLUSIONS: Combination therapy is effective in 60% of hepatitis C virus-5-infected patients. Sustained virological response seems better in hepatitis C virus-5 patients than in hepatitis C virus-1 patients, and is similar to that of hepatitis C virus-2-3 patients. More studies are needed to determine optimal duration of treatment in hepatitis C virus-5 patients.
Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Combinação de Medicamentos , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Retrospectivos , Resultado do TratamentoRESUMO
AIMS/HYPOTHESIS: The beta cell destruction and insulin deficiency that characterises type 1 diabetes mellitus is partially mediated by cytokines, such as IL-1beta, and by nitric oxide (NO)-dependent and -independent effector mechanisms. IL-1beta activates mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), p38 and c-Jun NH2-terminal kinase (JNK), and the nuclear factor kappa B (NFkappaB) pathway. Both pathways are required for expression of the gene encoding inducible nitric oxide synthase (iNOS) and for IL-1beta-mediated beta cell death. The molecular mechanisms by which these two pathways regulate beta cell Nos2 expression are currently unknown. Therefore, the aim of this study was to clarify the putative crosstalk between MAPK and NFkappaB activation in beta cells. MATERIALS AND METHODS: The MAPKs ERK, p38 and JNK were inhibited by SB203580, PD98059 or Tat-JNK binding domain or by cells overexpressing the JNK binding domain. The effects of MAPK inhibition on IL-1beta-induced iNOS production and kappa B inhibitor protein (IkappaB) degradation were examined by western blotting. NFkappaB DNA binding was investigated by electrophoretic mobility shift assay, while NFkappaB-induced gene transcription was evaluated by gene reporter assays. RESULTS: Inhibition of the MAPKs did not affect IkappaB degradation or NFkappaB DNA binding. However, inhibition of ERK reduced NFkappaB-mediated Nos2 expression; serine 276 phosphorylation of the p65 unit of the NFkappaB complex seemed critical, as evaluated by amino acid mutation analysis. CONCLUSIONS/INTERPRETATION: ERK activity is required for NFkappaB-mediated transcription of Nos2 in insulin-producing INS-1E cells, indicating that ERK regulates Nos2 expression by increasing the transactivating capacity of NFkappaB. This may involve phosphorylation of Ser276 on p65 by an as yet unidentified kinase.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Expressão Gênica , Células Secretoras de Insulina/fisiologia , Insulina/metabolismo , Interleucina-1/fisiologia , NF-kappa B/fisiologia , Óxido Nítrico Sintase Tipo II/genética , Animais , Apoptose/genética , Western Blotting , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Humanos , Imidazóis/farmacologia , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Interleucina-1/farmacologia , MAP Quinase Quinase 4/antagonistas & inibidores , MAP Quinase Quinase 4/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Óxido Nítrico Sintase Tipo II/biossíntese , Fosforilação , Piridinas/farmacologia , Ratos , Serina/análise , Sinaptotagmina I/química , Sinaptotagmina I/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologiaRESUMO
Both transcription factors albumin site d-binding protein (DBP) and thyrotroph embryonic factor (TEF) are elements of the "cell-clock". Their circadian accumulation in suprachiasmatic nucleus (SCN) and peripheral tissues such as liver, kidney and lung is thought to participate in controlling circadian regulation of downstream genes. TEF and DBP control elements have never been investigated in the insulin-secreting cells, but impairment of the circadian rhythm of the beta-cells might be involved in the development of diabetic state as type 2 diabetics have lost daily temporal variations of insulin secretion. We investigated the expression pattern of TEF and DBP in insulin-secreting cells. TEF and DBP transcripts are expressed at extremely high levels in human pancreatic islets compared to other tissues, suggesting a potentially important circadian regulation of these cells. Both TEF and DPB accumulate in a circadian way in insulin-secreting cells after a serum shock known to restore circadian rhythms in cultured cells. In addition, the expression of islet-specific genes involved in glucose sensing (glucose transporter 2 (Glut2), glucokinase), insulin production (insulin) and secretion (migration inhibitory factor (MIF), somatostatin and syntaxin 1A) were modulated in the same daily rhythm as well. The circadian deregulation of these genes could therefore participate in the diabetic state development.
Assuntos
Ritmo Circadiano , Proteínas de Ligação a DNA/metabolismo , Insulina/biossíntese , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Fatores de Transcrição/metabolismo , Antígenos de Superfície/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica , Regulação da Expressão Gênica , Glucoquinase/metabolismo , Transportador de Glucose Tipo 2 , Humanos , Secreção de Insulina , Fatores Inibidores da Migração de Macrófagos/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Regiões Promotoras Genéticas , Somatostatina/metabolismo , Núcleo Supraquiasmático/metabolismo , Sintaxina 1RESUMO
Bats submitted to the Texas Department of Health (1996-2000) were speciated and tested for rabies virus antigen by direct immunofluorescence microscopy. Antigenic analysis of rabies virus-positive specimens was performed with monoclonal antibodies against the nucleoprotein of the virus; atypical or unexpected results were confirmed by genetic analysis of nucleoprotein sequence.