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1.
Br J Hosp Med (Lond) ; 85(9): 1-21, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39347669

RESUMEN

Aims/Background Pre-frailty is common in patients undergoing maintenance hemodialysis (MHD). Without proper management, it can quickly worsen and progress into frailty, leading to various adverse clinical outcomes. Therefore, timely interventions for pre-frail MHD patients are crucial. However, the response of pre-frail MHD patients to such interventions is currently unclear. This study evaluated the effect of a multicomponent intervention on changes in pre-frailty status, risk factors for frailty, quality of life, and clinical outcomes in pre-frail patients undergoing MHD. Methods Sixty MHD patients were randomly assigned to intervention (received a 12-week multicomponent intervention) and control (received standard care) groups, with 30 participants per group, between February and May 2018. Data were collected at baseline and at 3 and 9 months thereafter. Analyzed outcomes included changes in pre-frailty status, frailty risk factors (such as albumin level, pain, and anxiety), quality of life, and clinical outcomes during the follow-up period. Results Data from a total of 58 MHD patients were collected at three time points. At week 12, frailty scores were 0.9 points lower in the intervention group compared to the control group (p = 0.007). The intervention group showed a 26.2% higher proportion of patients who improved from pre-frailty to non-frailty compared to the control group (p = 0.029), and a 25.9% lower proportion of patients who progressed from pre-frailty to frailty (p = 0.021). Additionally, improvements in albumin levels, pain, anxiety, and quality of life were more significant in the intervention group (all p < 0.05). Although there were fewer incidents of falls and rehospitalizations in the intervention group during follow-up, these differences did not reach statistical significance (all p > 0.05). Conclusion This study validates the effectiveness and practicality of a multicomponent intervention in improving pre-frailty status, frailty risk factors, and quality of life in patients undergoing MHD. Clinical Trial Registration Chinese Clinical Trial Registry (ChiCTR-IOR-17012176).


Asunto(s)
Fragilidad , Calidad de Vida , Diálisis Renal , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Factores de Riesgo , Fallo Renal Crónico/terapia
2.
Front Nutr ; 10: 1158769, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346907

RESUMEN

Background: Modifiable risk factors are major drivers of cardiovascular disease (CVD). We aimed to determine the epidemiological trend and age-period-cohort effects on CVD burden attributable to dietary risks and high body mass index (BMI) across China and Pakistan from 1990 to 2019. Methods: Data on the all-ages and age-specific CVD burden, age-standardized CVD mortality and disability-adjusted life years (DALYs) rates were obtained from the Global Burden of Disease Study 2019. Joinpoint regression analysis was conducted to find temporal trends and age-period-cohort (APC) modeling was used to estimate age, period, and cohort effects on CVD burden. Results: Between 1990 and 2019, the all-ages CVD burden attributable to dietary risks and high BMI increased by ~2-3-fold in China and by 3-5-fold in Pakistan. The diet-related CVD age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life years (DALYs) rate significantly decreased in China but increased in Pakistan. Both countries showed a marked increasing trend of CVD ASMR and the age-standardized DALYs rate attributable to high BMI. Taiwan in China showed a remarkable reduction in CVD burden. However, in Pakistan, all regions observed a significantly increasing trend of CVD burden attributable to modifiable risk factors. A higher risk ratio of premature CVD mortality (<70 years) was observed among Chinese attributable to high BMI and among Pakistani attributable to dietary risks. In China, early birth cohorts showed a higher risk ratio and recent birth cohorts experienced a lower risk ratio of CVD burden compared with Pakistan. Conclusion: In conclusion, dietary risks and high BMI caused a huge CVD burden across China and Pakistan.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(2): 539-542, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35395993

RESUMEN

OBJECTIVE: To investigate the difference of therapeutic effects on children with thalassemia at different age after hematopoietic stem cell transplantation. METHODS: The clinical data of children with thalassemia treated in our hospital were retrospectively analyzed. The children were divided into 2-5 years old group and 6-12 years old group. The success rate of implantation, transplant-related mortality, GVHD incidence, and other transplant-related complications, as well as thalassemia-free survival (TFS) were compared between the two groups. RESULTS: The incidence of GVHD, hemorrhagic cystitis and severe oral mucositis after transplantation in the 2-5 years old group were significantly lower than those in the 6-12 years old group, while there was no statistically significant difference in the TFS between the two groups. CONCLUSION: Children in the low age (2-5 years old) group show fewer complications and higher quality of life after transplantation, therefore, stem cell transplantation at 2-5 years old is more conducive to rehabilitation of the children with thalassemia.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Talasemia , Talasemia beta , Niño , Preescolar , Enfermedad Injerto contra Huésped/complicaciones , Humanos , Calidad de Vida , Estudios Retrospectivos , Talasemia/terapia , Talasemia beta/terapia
4.
PLoS One ; 11(11): e0167221, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27893810

RESUMEN

Influenza A virus (IAV) causes seasonal epidemics of respiratory illness that can cause mild to severe illness and potentially death. Antiviral drugs are an important countermeasure against IAV; however, drug resistance has developed, thus new therapeutic approaches are being sought. Previously, we demonstrated the antiviral activity of a novel nuclear export inhibitor drug, verdinexor, to reduce influenza replication in vitro and pulmonary virus burden in mice. In this study, in vivo efficacy of verdinexor was further evaluated in two animal models or influenza virus infection, mice and ferrets. In mice, verdinexor was efficacious to limit virus shedding, reduce pulmonary pro-inflammatory cytokine expression, and moderate leukocyte infiltration into the bronchoalveolar space. Similarly, verdinexor-treated ferrets had reduced lung pathology, virus burden, and inflammatory cytokine expression in the nasal wash exudate. These findings support the anti-viral efficacy of verdinexor, and warrant its development as a novel antiviral therapeutic for influenza infection.


Asunto(s)
Acrilamidas/uso terapéutico , Transporte Activo de Núcleo Celular/efectos de los fármacos , Antivirales/uso terapéutico , Modelos Animales de Enfermedad , Hidrazinas/uso terapéutico , Virus de la Influenza A/efectos de los fármacos , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Animales , Femenino , Hurones , Masculino , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/virología , Replicación Viral/efectos de los fármacos , Esparcimiento de Virus/efectos de los fármacos
5.
Assay Drug Dev Technol ; 13(10): 638-49, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26192013

RESUMEN

Influenza A virus (IAV) infection causes seasonal epidemics of contagious respiratory illness that causes substantial morbidity and some mortality. Regular vaccination is the principal strategy for controlling influenza virus, although vaccine efficacy is variable. IAV antiviral drugs are available; however, substantial drug resistance has developed to two of the four currently FDA-approved antiviral drugs. Thus, new therapeutic approaches are being sought to reduce the burden of influenza-related disease. A high-throughput screen using a human kinase inhibitor library was performed targeting an emerging IAV strain (H7N9) in A549 cells. The inhibitor library contained 273 structurally diverse, active cell permeable kinase inhibitors with known bioactivity and safety profiles, many of which are at advanced stages of clinical development. The current study shows that treatment of human A549 cells with kinase inhibitors dinaciclib, flavopiridol, or PIK-75 exhibits potent antiviral activity against H7N9 IAV as well as other IAV strains. Thus, targeting host kinases can provide a broad-spectrum therapeutic approach against IAV. These findings provide a path forward for repurposing existing kinase inhibitors safely as potential antivirals, particularly those that can be tested in vivo and ultimately for clinical use.


Asunto(s)
Antivirales/farmacología , Reposicionamiento de Medicamentos/métodos , Virus de la Influenza A/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Replicación Viral/efectos de los fármacos , Antivirales/efectos adversos , Línea Celular , Relación Dosis-Respuesta a Droga , Farmacorresistencia Viral , Sinergismo Farmacológico , Ensayos Analíticos de Alto Rendimiento , Humanos , Subtipo H7N9 del Virus de la Influenza A/efectos de los fármacos , Inhibidores de Proteínas Quinasas/efectos adversos , Seguridad , Bibliotecas de Moléculas Pequeñas
6.
J Virol ; 88(17): 10228-43, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-24965445

RESUMEN

UNLABELLED: Influenza is a global health concern, causing death, morbidity, and economic losses. Chemotherapeutics that target influenza virus are available; however, rapid emergence of drug-resistant strains is common. Therapeutic targeting of host proteins hijacked by influenza virus to facilitate replication is an antiviral strategy to reduce the development of drug resistance. Nuclear export of influenza virus ribonucleoprotein (vRNP) from infected cells has been shown to be mediated by exportin 1 (XPO1) interaction with viral nuclear export protein tethered to vRNP. RNA interference screening has identified XPO1 as a host proinfluenza factor where XPO1 silencing results in reduced influenza virus replication. The Streptomyces metabolite XPO1 inhibitor leptomycin B (LMB) has been shown to limit influenza virus replication in vitro; however, LMB is toxic in vivo, which makes it unsuitable for therapeutic use. In this study, we tested the anti-influenza virus activity of a new class of orally available small-molecule selective inhibitors of nuclear export, specifically, the XPO1 antagonist KPT-335 (verdinexor). Verdinexor was shown to potently and selectively inhibit vRNP export and effectively inhibited the replication of various influenza virus A and B strains in vitro, including pandemic H1N1 virus, highly pathogenic H5N1 avian influenza virus, and the recently emerged H7N9 strain. In vivo, prophylactic and therapeutic administration of verdinexor protected mice against disease pathology following a challenge with influenza virus A/California/04/09 or A/Philippines/2/82-X79, as well as reduced lung viral loads and proinflammatory cytokine expression, while having minimal toxicity. These studies show that verdinexor acts as a novel anti-influenza virus therapeutic agent. IMPORTANCE: Antiviral drugs represent important means of influenza virus control. However, substantial resistance to currently approved influenza therapeutic drugs has developed. New antiviral approaches are required to address drug resistance and reduce the burden of influenza virus-related disease. This study addressed critical preclinical studies for the development of verdinexor (KPT-335) as a novel antiviral drug. Verdinexor blocks progeny influenza virus genome nuclear export, thus effectively inhibiting virus replication. Verdinexor was found to limit the replication of various strains of influenza A and B viruses, including a pandemic H1N1 influenza virus strain, a highly pathogenic H5N1 avian influenza virus strain, and a recently emerging H7N9 influenza virus strain. Importantly, oral verdinexor treatments, given prophylactically or therapeutically, were efficacious in limiting lung virus burdens in influenza virus-infected mice, in addition to limiting lung proinflammatory cytokine expression, pathology, and death. Thus, this study demonstrated that verdinexor is efficacious against influenza virus infection in vitro and in vivo.


Asunto(s)
Transporte Activo de Núcleo Celular/efectos de los fármacos , Antivirales/metabolismo , Inhibidores Enzimáticos/metabolismo , Virus de la Influenza A/fisiología , Virus de la Influenza B/fisiología , Carioferinas/antagonistas & inhibidores , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Replicación Viral/efectos de los fármacos , Animales , Antivirales/uso terapéutico , Línea Celular , Quimioprevención/métodos , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/uso terapéutico , Femenino , Humanos , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza B/efectos de los fármacos , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/prevención & control , Proteína Exportina 1
7.
J Virol ; 87(24): 13775-84, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24109234

RESUMEN

Influenza virus is a worldwide global health concern causing seasonal morbidity mortality and economic burden. Chemotherapeutics is available; however, rapid emergence of drug-resistant influenza virus strains has reduced its efficacy. Thus, there is a need to discover novel antiviral agents. In this study, RNA interference (RNAi) was used to screen host genes required for influenza virus replication. One pro-influenza virus host gene identified was dual-specificity phosphatase cell division cycle 25 B (CDC25B). RNAi screening of CDC25B resulted in reduced influenza A virus replication, and a CDC25B small-molecule inhibitor (NSC95397) inhibited influenza A virus replication in a dose-dependent fashion. Viral RNA synthesis was reduced by NSC95397 in favor of increased beta interferon (IFN-ß) expression, and NSC95397 was found to interfere with nuclear localization and chromatin association of NS1, an influenza virus protein. As NS1 has been shown to be chromatin associated and to suppress host transcription, it is likely that CDC25B supports NS1 nuclear function to hijack host transcription machinery in favor of viral RNA synthesis, a process that is blocked by NSC95397. Importantly, NSC95397 treatment protects mice against lethal influenza virus challenge. The findings establish CDC25B as a pro-influenza A virus host factor that may be targeted as a novel influenza A therapeutic strategy.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/fisiología , Virus de la Influenza B/fisiología , Gripe Humana/enzimología , Replicación Viral , Fosfatasas cdc25/genética , Fosfatasas cdc25/metabolismo , Animales , Línea Celular , Femenino , Marcación de Gen , Interacciones Huésped-Patógeno , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Virus de la Influenza B/genética , Gripe Humana/genética , Gripe Humana/virología , Interferón beta/genética , Interferón beta/metabolismo , Ratones , Ratones Endogámicos BALB C , Interferencia de ARN
8.
PLoS One ; 8(6): e66796, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23805279

RESUMEN

Human protein kinases (HPKs) have profound effects on cellular responses. To better understand the role of HPKs and the signaling networks that influence influenza virus replication, a small interfering RNA (siRNA) screen of 720 HPKs was performed. From the screen, 17 HPKs (NPR2, MAP3K1, DYRK3, EPHA6, TPK1, PDK2, EXOSC10, NEK8, PLK4, SGK3, NEK3, PANK4, ITPKB, CDC2L5 (CDK13), CALM2, PKN3, and HK2) were validated as essential for A/WSN/33 influenza virus replication, and 6 HPKs (CDK13, HK2, NEK8, PANK4, PLK4 and SGK3) were identified as vital for both A/WSN/33 and A/New Caledonia/20/99 influenza virus replication. These HPKs were found to affect multiple host pathways and regulated by miRNAs induced during infection. Using a panel of miRNA agonists and antagonists, miR-149* was found to regulate NEK8 expression, miR-548d-3p was found to regulate MAPK1 transcript expression, and miRs -1228 and -138 to regulate CDK13 expression. Up-regulation of miR-34c induced PLK4 transcript and protein expression and enhanced influenza virus replication, while miR-34c inhibition reduced viral replication. These findings identify HPKs important for influenza viral replication and show the miRNAs that govern their expression.


Asunto(s)
Virus de la Influenza A/fisiología , Gripe Humana/genética , Gripe Humana/virología , MicroARNs/metabolismo , Proteínas Quinasas/metabolismo , Replicación Viral/genética , Células A549 , Animales , Secuencia de Bases , Perros , Humanos , Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , Gripe Humana/enzimología , Gripe Humana/patología , Quinasa 1 de Quinasa de Quinasa MAP/antagonistas & inhibidores , Quinasa 1 de Quinasa de Quinasa MAP/genética , Quinasa 1 de Quinasa de Quinasa MAP/metabolismo , Células de Riñón Canino Madin Darby , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , Quinasas Relacionadas con NIMA/antagonistas & inhibidores , Quinasas Relacionadas con NIMA/genética , Quinasas Relacionadas con NIMA/metabolismo , Proteínas de la Nucleocápside , Fenotipo , Proteínas Quinasas/química , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/metabolismo , Proteínas de Unión al ARN/metabolismo , Alineación de Secuencia , Regulación hacia Arriba , Proteínas del Núcleo Viral/metabolismo
9.
Antimicrob Agents Chemother ; 57(1): 475-83, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23129053

RESUMEN

Influenza A virus infection is a major global health concern causing significant mortality, morbidity, and economic loss. Antiviral chemotherapeutics that target influenza A virus are available; however, rapid emergence of drug-resistant strains has been reported. Consequently, there is a burgeoning need to identify novel anti-influenza A drugs, particularly those that target host gene products required for virus replication, to reduce the likelihood of drug resistance. In this study, a small interfering RNA (siRNA) screen was performed to identify host druggable gene targets for anti-influenza A virus therapy. The host organic anion transporter-3 gene (OAT3), a member of the SLC22 family of transporters, was validated as being required to support influenza A virus replication. Probenecid, a prototypical uricosuric agent and chemical inhibitor of organic anion transporters known to target OAT3, was shown to be effective in limiting influenza A virus infection in vitro (50% inhibitory concentration [IC(50)] of 5.0 × 10(-5) to 5.0 × 10(-4) µM; P < 0.005) and in vivo (P < 0.05). Probenecid is widely used for treatment of gout and related hyperuricemic disorders, has been extensively studied for pharmacokinetics and safety, and represents an excellent candidate for drug repositioning as a novel anti-influenza A chemotherapeutic.


Asunto(s)
Antivirales/farmacología , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Transportadores de Anión Orgánico Sodio-Independiente/antagonistas & inhibidores , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Probenecid/farmacología , Uricosúricos/farmacología , Línea Celular , Reposicionamiento de Medicamentos , Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Interacciones Huésped-Patógeno , Humanos , Subtipo H1N1 del Virus de la Influenza A/fisiología , Subtipo H3N2 del Virus de la Influenza A/fisiología , Gripe Humana/tratamiento farmacológico , Gripe Humana/virología , Concentración 50 Inhibidora , Transportadores de Anión Orgánico Sodio-Independiente/genética , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Infecciones por Orthomyxoviridae/virología , Unión Proteica , ARN Interferente Pequeño/genética , Replicación Viral/efectos de los fármacos
10.
PLoS One ; 7(5): e37169, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22606348

RESUMEN

Influenza A virus causes seasonal epidemics and periodic pandemics threatening the health of millions of people each year. Vaccination is an effective strategy for reducing morbidity and mortality, and in the absence of drug resistance, the efficacy of chemoprophylaxis is comparable to that of vaccines. However, the rapid emergence of drug resistance has emphasized the need for new drug targets. Knowledge of the host cell components required for influenza replication has been an area targeted for disease intervention. In this study, the human protease genes required for influenza virus replication were determined and validated using RNA interference approaches. The genes validated as critical for influenza virus replication were ADAMTS7, CPE, DPP3, MST1, and PRSS12, and pathway analysis showed these genes were in global host cell pathways governing inflammation (NF-κB), cAMP/calcium signaling (CRE/CREB), and apoptosis. Analyses of host microRNAs predicted to govern expression of these genes showed that eight miRNAs regulated gene expression during virus replication. These findings identify unique host genes and microRNAs important for influenza replication providing potential new targets for disease intervention strategies.


Asunto(s)
Virus de la Influenza A/fisiología , MicroARNs/genética , Péptido Hidrolasas/genética , Replicación Viral/genética , Proteínas ADAM/antagonistas & inhibidores , Proteínas ADAM/genética , Proteína ADAMTS7 , Secuencia de Bases , Carboxipeptidasa H/antagonistas & inhibidores , Carboxipeptidasa H/genética , Línea Celular , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/antagonistas & inhibidores , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/genética , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/fisiología , Humanos , Virus de la Influenza A/patogenicidad , Gripe Humana/enzimología , Gripe Humana/genética , Gripe Humana/virología , Péptidos y Proteínas de Señalización Intracelular , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Serina Endopeptidasas/genética
11.
Genome Res ; 20(3): 341-50, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20086242

RESUMEN

Human colorectal cancer (CRC) is one of the better-understood systems for studying the genetics of cancer initiation and progression. To develop a cross-species comparison strategy for identifying CRC causative gene or genomic alterations, we performed array comparative genomic hybridization (aCGH) to investigate copy number abnormalities (CNAs), one of the most prominent lesion types reported for human CRCs, in 10 spontaneously occurring canine CRCs. The results revealed for the first time a strong degree of genetic homology between sporadic canine and human CRCs. First, we saw that between 5% and 22% of the canine genome was amplified/deleted in these tumors, and that, reminiscent of human CRCs, the total altered sequences directly correlated to the tumor's progression stage, origin, and likely microsatellite instability status. Second, when mapping the identified CNAs onto syntenic regions of the human genome, we noted that the canine orthologs of genes participating in known human CRC pathways were recurrently disrupted, indicating that these pathways might be altered in the canine CRCs as well. Last, we observed a significant overlapping of CNAs between human and canine tumors, and tumors from the two species were clustered according to the tumor subtypes but not the species. Significantly, compared with the shared CNAs, we found that species-specific (especially human-specific) CNAs localize to evolutionarily unstable regions that harbor more segmental duplications and interspecies genomic rearrangement breakpoints. These findings indicate that CNAs recurrent between human and dog CRCs may have a higher probability of being cancer-causative, compared with CNAs found in one species only.


Asunto(s)
Neoplasias Colorrectales/genética , Genoma Humano , Genoma , Inestabilidad de Microsatélites , Duplicaciones Segmentarias en el Genoma , Animales , Análisis por Conglomerados , Neoplasias Colorrectales/patología , Hibridación Genómica Comparativa/métodos , Perros , Humanos , Eliminación de Secuencia
12.
J Pharmacol Exp Ther ; 330(1): 352-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19372387

RESUMEN

Botulinum neurotoxins (BoNTs) are extremely potent neuromuscular poisons that act through soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein cleavage to inhibit neurotransmitter release. The ability of BoNT serotype A (BoNT/A) to eliminate localized transmitter release at extremely low doses is well characterized. In the current study, we investigated the less understood characteristic of BoNT/A to induce nerve outgrowth, sometimes referred to as sprouting. This phenomenon is generally considered a secondary response to the paralytic actions of BoNT/A, and other potential factors that may initiate this sprouting have not been investigated. Alternatively, we hypothesized that BoNT/A induces sprouting through presynaptic receptor activation that is independent of its known intracellular actions on the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) synaptosomal associated protein of 25 kDa (SNAP-25). To test this, the effects of BoNT/A application on neurite outgrowth were examined using primary cultures enriched with motor neurons isolated from embryonic mouse spinal cord. In this system, BoNT/A potently stimulated neuritogenesis at concentrations as low as 0.01 nM. The neuritogenic effects of BoNT/A exposure were concentration dependent and antagonized by Triticum vulgaris lectin, a known competitive antagonist of BoNT. Similar results were observed with the isolated BoNT/A binding domain, revealing that neuritogenesis could be initiated solely by the binding actions of BoNT/A. In addition, the presence or absence of SNAP-25 cleavage by BoNT/A was not a determinant factor in BoNT/A-induced neuritogenesis. Collectively, these results suggest that binding of BoNT/A to the motor neuronal membrane activates neuritogenesis through as yet undetermined intracellular pathway(s), independent of its known action on vesicular release.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Células Madre Embrionarias/fisiología , Neuronas Motoras/fisiología , Neuritas/fisiología , Neurogénesis/fisiología , Animales , Células Cultivadas , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/microbiología , Vesículas Citoplasmáticas/fisiología , Células Madre Embrionarias/citología , Células Madre Embrionarias/microbiología , Femenino , Líquido Intracelular/microbiología , Líquido Intracelular/fisiología , Ratones , Neuronas Motoras/citología , Neuronas Motoras/microbiología , Neuritas/microbiología , Embarazo , Transducción de Señal/fisiología
13.
Inhal Toxicol ; 18(14): 1109-16, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17043031

RESUMEN

Brevetoxins (polyether breve toxins; PbTx) are polyether neurotoxins produced by the marine dinoflagellate Karenia brevis, an organism associated with red tide blooms in the Gulf of Mexico and along the Atlantic coast from Florida to North Carolina. Brevetoxin-3 (PbTx-3) is a major component of the array of brevetoxins found in marine aerosols measured along red tide affected beaches. Humans exposed to aerosolized brevetoxins for short periods of time often suffer a variety of adverse health effects. It was consequently of interest to assess the potential for aerosolized brevetoxin to produce a neurotoxic response. Female BALB/c mice were exposed nose-only for 2 consecutive days to PbTx-3 aerosol, with a 2-h exposure on the first day and a 4-h exposure on the second day. The average PbTx-3 exposure concentrations on days 1 and 2 were 312 +/- 113 mug brevetoxin 3/m3 and 278 +/- 24 mug brevetoxin 3/m3, respectively. The brevetoxin-containing aerosol had a mass median aerodynamic diameter of 0.92 mum with a geometric standard deviation of 1.38. Coronal sections of mouse brains were evaluated for neuronal damage using both silver and Fluoro-Jade B staining to identify degenerating neuronal elements. PbTx-3 inhalation exposure produced neuronal degeneration in the posterior cingulate/retrosplenial cortex of mice as evidenced by silver-positive degenerating neurons in this region. No staining was found in other regions of the PBTx-3-exposed mouse brains or in brains of control, sham-exposed mice. The existence of a neurotoxic insult in PbTx-3-exposed mice was confirmed using Fluoro-Jade B to label degenerating neurons. Fluro-Jade-positive neurons were observed in the retrosplenial cortex of PBTx-3 exposed, but not control, mice. These results suggest that subacute exposure to PbTx-3 for 2 days is sufficient to induce neuronal degeneration in a discrete region of the mouse cerebral cortex.


Asunto(s)
Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Toxinas Marinas/toxicidad , Oxocinas/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Femenino , Exposición por Inhalación , Ratones , Ratones Endogámicos BALB C , Neuronas/efectos de los fármacos
14.
J Med Chem ; 48(14): 4500-3, 2005 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-15999987

RESUMEN

The cyclic dynorphin A analogue [N(alpha)-benzylTyr(1),cyclo(D-Asp(5),Dap(8))]dynorphin A-(1-11)NH(2) (Dap = 2,3-diaminopropionic acid) exhibits nanomolar affinity (30 nM) and high selectivity (K(i) ratio (kappa/mu/delta) = 1/194/330) for kappa-opioid receptors. This analogue antagonizes dynorphin A-(1-13)NH(2) at kappa-opioid receptors in the adenylyl cyclase assay (K(B) = 84 nM). This is the first dynorphin A-based antagonist with modifications in the C-terminal "address" domain that alter efficacy and thus represents a novel selective kappa-opioid receptor antagonist.


Asunto(s)
Dinorfinas/síntesis química , Fragmentos de Péptidos/síntesis química , Receptores Opioides kappa/antagonistas & inhibidores , Adenilil Ciclasas/biosíntesis , Animales , Células CHO , Cricetinae , Cricetulus , Ciclización , Dinorfinas/química , Dinorfinas/farmacología , Conformación Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacología , Estructura Terciaria de Proteína , Ensayo de Unión Radioligante , Relación Estructura-Actividad
15.
J Neurovirol ; 8(4): 345-52, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12161819

RESUMEN

The contribution of rabies virus (RV) glycoprotein (G) in viral distribution in the brain was examined by immunohistochemistry following stereotaxic inoculation into the rat hippocampus. Viruses used in this study include the highly neuroinvasive challenge virus standard strains (CVS-N2C and CVS-B2C) and the nonneuroinvasive attenuated SN-10 strain, as well as SN-10-derived recombinant viruses expressing the G gene from CVS-N2C (RN2C) or CVS-B2C (RB2C). The distribution of recombinant viruses in the brain was similar to those of the parental viruses from which the G was derived. For example, while CVS-B2C- and RB2C-infected neurons were seen preferentially in the hippocampus, cortex, and hypothalamus, CVS-N2C- and RN2C-infected neurons were preferentially found in the hippocampus, cortex, and thalamus. SN-10 infected efficiently almost all the brain regions. To further study the role of the RV G in virus spreading, we examined the distribution of RV antigen in brains infected with a recombinant RV in which the SN-10 G was replaced with vesicular stomatitis virus (VSV) G (SN-10-VG) was examined. The spreading of SN-10-VG to the cortex and the thalamus was drastically reduced, but the number of infected neurons in hippocampus and hypothalamus, particularly the paraventricular nucleus, was similar to the SN-10 virus. This pattern of spreading resembles that of VSV. Together, our data demonstrate that it is the G protein that determines the distribution pattern of RV in the brain.


Asunto(s)
Antígenos Virales , Encéfalo/virología , Glicoproteínas/genética , Virus de la Rabia/genética , Rabia/virología , Proteínas del Envoltorio Viral/genética , Sustitución de Aminoácidos/genética , Animales , Encéfalo/patología , Glicoproteínas/análisis , Inmunohistoquímica , Mutagénesis/fisiología , Mutación Puntual , Virus de la Rabia/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas del Envoltorio Viral/análisis
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