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1.
Biol Open ; 13(6)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38875000

RESUMO

Viral infectivity depends on multiple factors. Recent studies showed that the interaction between viral RNAs and endogenous microRNAs (miRNAs) regulates viral infectivity; viral RNAs function as a sponge of endogenous miRNAs and result in upregulation of its original target genes, while endogenous miRNAs target viral RNAs directly and result in repression of viral gene expression. In this study, we analyzed the possible interaction between parainfluenza virus RNA and endogenous miRNAs in human and mouse lungs. We showed that the parainfluenza virus can form base pairs with human miRNAs abundantly than mouse miRNAs. Furthermore, we analyzed that the sponge effect of endogenous miRNAs on viral RNAs may induce the upregulation of transcription regulatory factors. Then, we performed RNA-sequence analysis and observed the upregulation of transcription regulatory factors in the early stages of parainfluenza virus infection. Our studies showed how the differential expression of endogenous miRNAs in lungs could contribute to respiratory virus infection and species- or tissue-specific mechanisms and common mechanisms could be conserved in humans and mice and regulated by miRNAs during viral infection.


Assuntos
Pulmão , MicroRNAs , Animais , MicroRNAs/genética , Camundongos , Humanos , Pulmão/virologia , Pulmão/imunologia , Pulmão/metabolismo , RNA Viral/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Regulação da Expressão Gênica , Infecções Respiratórias/imunologia , Infecções Respiratórias/virologia , Infecções Respiratórias/genética , Infecções por Respirovirus/imunologia
2.
Nucleic Acids Res ; 52(9): 5209-5225, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38636948

RESUMO

RNA silencing is a post-transcriptional gene-silencing mechanism mediated by microRNAs (miRNAs). However, the regulatory mechanism of RNA silencing during viral infection is unclear. TAR RNA-binding protein (TRBP) is an enhancer of RNA silencing that induces miRNA maturation by interacting with the ribonuclease Dicer. TRBP interacts with a virus sensor protein, laboratory of genetics and physiology 2 (LGP2), in the early stage of viral infection of human cells. Next, it induces apoptosis by inhibiting the maturation of miRNAs, thereby upregulating the expression of apoptosis regulatory genes. In this study, we show that TRBP undergoes a functional conversion in the late stage of viral infection. Viral infection resulted in the activation of caspases that proteolytically processed TRBP into two fragments. The N-terminal fragment did not interact with Dicer but interacted with type I interferon (IFN) signaling modulators, such as protein kinase R (PKR) and LGP2, and induced ER stress. The end results were irreversible apoptosis and suppression of IFN signaling. Our results demonstrate that the processing of TRBP enhances apoptosis, reducing IFN signaling during viral infection.


Assuntos
Apoptose , Caspases , Proteínas de Ligação a RNA , Humanos , Caspases/metabolismo , Linhagem Celular , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Estresse do Retículo Endoplasmático/genética , Células HEK293 , Células HeLa , Interferon Tipo I/metabolismo , Interferon Tipo I/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Ribonuclease III/metabolismo , Ribonuclease III/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Viroses/genética , Viroses/metabolismo
4.
Nihon Shokakibyo Gakkai Zasshi ; 116(8): 676-684, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31406073

RESUMO

A 42-year-old woman was referred to our hospital for the treatment of pyloric stenosis. Esophagogastroduodenoscopy (EGD) and computed tomography (CT) revealed the presence of type 4 advanced gastric cancer with bladder metastasis and peritoneal dissemination. Biopsy specimen examination revealed poorly differentiated adenocarcinoma with signet ring cell carcinoma. Thus, two cycles of chemotherapy with 5-fluorouracil, leucovorin, and oxaliplatin were administered. Subsequently, the gastric lesion and bladder metastasis reduced as detected using EGD and CT. Consequently, she achieved adequate oral intake. After changing the regimen to tegafur/gimeracil/oteracil and oxaliplatin, she was discharged. Currently, she continues to receive chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/diagnóstico , Neoplasias da Bexiga Urinária/secundário , Adulto , Feminino , Humanos , Leucovorina/uso terapêutico , Compostos Organoplatínicos/uso terapêutico , Neoplasias Gástricas/terapia , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia
5.
Cancer Chemother Pharmacol ; 84(3): 647-654, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31230157

RESUMO

PURPOSE: To evaluate the efficacy and safety of nab paclitaxel (nab-P) plus gemcitabine (GEM) in elderly patients ≥ 75 years old with unresectable pancreatic cancer (PC) compared with younger patients. METHODS: The data of 27 unresectable PC patients treated with nab-P plus GEM as first-line chemotherapy were retrospectively analyzed. The patients were divided into two groups according to their age at inclusion: an elderly group (9 patients ≥ 75 years old) and a younger group (18 patients <75 years old). We compared the disease control rate, median overall survival (OS), and adverse events (AEs) between the two groups. Predictive factors for the OS were also evaluated. RESULTS: The clinical characteristics of patients of the two groups were not significantly different except for the age. The respective values for the disease control rate (66.7% vs. 77.8%, P = 0.542) and median OS (277 days vs. 312 days, P = 0.722) were also not significantly different between the elderly and younger group, although the relative dose intensity of GEM/nab-P in the elderly group (56.6%/53.1%) was significantly lower than that in the younger group (67.3%/63.1%) (P = 0.016/0.04). The absence of biliary drainage and CEA ≥ 6.5 were found to be poor prognostic factors in a multivariate analysis. The most common grade ≥ 3 AE was neutropenia (44% in both groups). No significant differences in the frequency of all AEs were observed between the two groups. CONCLUSIONS: Nab-P plus GEM appears effective and well-tolerated for elderly patients ≥ 75 years old with unresectable PC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminas/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/patologia , Segurança do Paciente , Neoplasias Peritoneais/secundário , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Gencitabina
6.
Gan To Kagaku Ryoho ; 45(9): 1361-1363, 2018 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-30237382

RESUMO

A 61-year-old man was referred to the urology department in our hospital with gross hematuria and hydro nephrosis. Cystoscopy revealed a smooth mass lesion in his bladder, and a transurethral biopsy was performed. Signet ring cell carcinoma was found in the submucosa. Upper gastrointestinal endoscopy revealed an ulcerated lesion in his gastric body. Biopsy specimens obtained from the ulcerated lesion showed signet ring cell carcinoma. No other primary lesions were detected using colonoscopy, gallium scintigraphy, or computed tomography of the chest. He was ultimately diagnosed with advanced gastric cancer with bladder metastasis. He was prescribed combination chemotherapy of cisplatin and tegafur, gimeracil, oteracil potassium, and trastuzumab. After 2 courses of chemotherapy, there was a decrease in the size of both the gastric and bladder lesions. There was also a significant decrease in the tumor marker levels. He is currently alive after 7 courses of chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/patologia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/secundário
7.
Breast Cancer Res Treat ; 167(2): 439-450, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29027049

RESUMO

PURPOSE: Circulating tumor cells (CTCs) can provide a potentially minimal invasive source for monitoring chemotherapeutic effects. However, detailed in vivo dynamics of CTC after chemotherapy remain largely unknown. METHODS: We monitored CTC number and morphology early after chemotherapy using a newly developed cytology-based CTC detection device and triple-negative breast cancer mouse CTC models with spontaneous lung metastatic potential. RESULTS: Paclitaxel inhibited cell growth of breast cancer cells by mainly G2/M cell cycle arrest and partly apoptosis, whereas doxorubicin inhibited cell growth mainly by apoptosis and partly G2 cell cycle arrest in vitro. The number of CTCs was significantly increased 3-10 days after paclitaxel and doxorubicin chemotherapy and decreased thereafter in two mouse CTC models. The transiently increased CTCs early post-chemotherapy consisted of not only G2/M arrested cells (apoptotic cells), but also morphologically near-intact live cells. This heterogeneous cell population of CTCs was similar to that of primary tumor tissue after chemotherapy. CONCLUSIONS: These results indicate that CTCs can be mobilized from the primary tumor in rapid response to chemotherapy and suggest the possibility that CTC monitoring from both numerical and morphological viewpoints early after chemotherapy using a cytology-based CTC detection device would be a useful diagnostic tool for predicting drug sensitivity/resistance in preclinical and clinical setting.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Neoplasias Mamárias Animais/tratamento farmacológico , Paclitaxel/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Doxorrubicina/sangue , Feminino , Humanos , Neoplasias Mamárias Animais/sangue , Neoplasias Mamárias Animais/patologia , Camundongos , Células Neoplásicas Circulantes , Paclitaxel/sangue , Prognóstico
8.
World J Gastroenterol ; 23(45): 8097-8103, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29259386

RESUMO

We report the first use of endoscopic submucosal dissection (ESD) for the treatment of a patient with adenoid cystic carcinoma of the esophagus (EACC). An 82-year-old woman visited our hospital for evaluation of an esophageal submucosal tumor. Endoscopic examination showed a submucosal tumor in the middle third of the esophagus. The lesion partially stained with Lugol's solution, and narrow band imaging with magnification showed intrapapillary capillary loops with mild dilatation and a divergence of caliber in the center of the lesion. Endoscopic ultrasound imaging revealed a solid 8 mm × 4.2 mm tumor, primarily involving the second and third layers of the esophagus. A preoperative biopsy was non-diagnostic. ESD was performed to resect the lesion, an 8 mm submucosal tumor. Immunohistologically, tumor cells differentiating into ductal epithelium and myoepithelium were observed, and the tissue type was adenoid cystic carcinoma. There was no evidence of esophageal wall, vertical stump or horizontal margin invasion with pT1b-SM2 staining (1800 µm from the muscularis mucosa). Further studies are needed to assess the use of ESD for the treatment of patients with EACC.


Assuntos
Carcinoma Adenoide Cístico/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Neoplasias Esofágicas/cirurgia , Esofagoscopia/métodos , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Adenoide Cístico/diagnóstico , Carcinoma Adenoide Cístico/patologia , Carcinoma de Células Escamosas/diagnóstico , Diagnóstico Diferencial , Endossonografia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Esôfago/cirurgia , Feminino , Tumores do Estroma Gastrointestinal/diagnóstico , Humanos , Mucosa/patologia , Mucosa/cirurgia , Imagem de Banda Estreita , Resultado do Tratamento
9.
World J Gastroenterol ; 23(27): 5034-5040, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28785156

RESUMO

We are reporting a rare case of acute liver injury that developed after an internal hemorrhoid treatment with the aluminum potassium sulfate and tannic acid (ALTA) regimen. A 41-year-old man developed a fever and liver injury after undergoing internal hemorrhoid treatment with a submucosal injection of ALTA with lidocaine. The acute liver injury was classified clinically as hepatocellular and pathologically as cholestastic. We could not classify the mechanism of injury. High eosinophil and immunoglobulin E levels characterized the injury, and a drug lymphocyte stimulation test was negative on postoperative day 25. Fluid replacement for two weeks after hospitalization improved the liver injury. ALTA therapy involves injecting chemicals into the submucosa, from the rectum to the anus, and this is the first description of a case that developed a severe liver disorder after this treatment; hence, an analysis of future cases as they accumulate is desirable.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hemorroidas/terapia , Injeções Intralesionais/efeitos adversos , Soluções Esclerosantes/efeitos adversos , Escleroterapia/efeitos adversos , Adulto , Compostos de Alúmen/administração & dosagem , Compostos de Alúmen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/sangue , Febre/sangue , Febre/etiologia , Humanos , Lidocaína/administração & dosagem , Lidocaína/efeitos adversos , Fígado/efeitos dos fármacos , Testes de Função Hepática , Masculino , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Soluções Esclerosantes/administração & dosagem , Escleroterapia/métodos , Taninos/administração & dosagem , Taninos/efeitos adversos
10.
Oncol Res ; 20(4): 179-85, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23461065

RESUMO

No established supportive therapy to prevent and treat chemotherapy-induced peripheral neuropathy (PN) is available. Minimizing the severity of PN is therefore critical in clinical use. We aimed to determine when and how often PN occurs in association with paclitaxel plus carboplatin (PC therapy), a regimen used to treat non-small cell lung cancer, and factors that exacerbate this condition. Patients who received PC therapy for non-small cell lung cancer at the Japanese Foundation for Cancer Research, Cancer Institute Hospital, between May 20, 2009, and November 30, 2010, were included. PN was evaluated by the study pharmacist using specific questions based on the Common Terminology Criteria for Adverse Events Version 3.0. Univariate analysis was used to compare a group with no, Grade 1, or Grade 2 PN (non-serious) and a group with Grade 3 PN (serious). Analyses were conducted using the Cox proportional hazard model with patient characteristics having p < or = 0.20 when assessed as independent variables. Of 50 patients, 38 (76.0%) developed PN by day 6 of the first course of anticancer treatment. Grade 3 PN had an incidence of 25.0% in the fourth course. In multivariate analysis with the Cox proportional hazard model, pack-year [hazard ratio = 1.029; 95% confidence interval (CI): 1.009-1.050, p = 0.005] and creatinine clearance (hazard ratio = 0.957; 95% CI: 0.920-0.996, p = 0.031) were significant factors. A high pack-year and a low creatinine clearance exacerbated PN in patients treated with PC. PN must be carefully evaluated in patients with exacerbating factors.


Assuntos
Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
11.
Exp Neurol ; 219(1): 74-80, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19306874

RESUMO

Miller-Fisher syndrome (MFS), which is known to be associated with anti-GQ1b antibodies and to cause ataxia, is a variant of an acute inflammatory neuropathy. However, the pathogenic role of anti-GQ1b antibodies remains unclear. In this study, we investigated the effects of mouse IgM anti-GQ1b monoclonal antibody (IgM anti-GQ1b mAb) on the spontaneous muscle action potential of a rat spinal cord-muscle co-culture system and on the voltage-dependent calcium channel (VDCC) current in cerebellar granule cells and Purkinje cells using the whole-cell patch clamp technique. The frequency of spontaneous muscle action potential of the innervated muscle cells was transiently increased by IgM anti-GQ1b mAb and then was blocked completely, which was the same finding as reported previously. Moreover, the cerebellar granule cell VDCC current was decreased by 30.76+/-7.60% by 5 microg/mL IgM anti-GQ1b mAb, whereas IgM anti-GQ1b mAb did not affect the VDCC current in cerebellar Purkinje cells. In immunocytochemistry, IgM anti-GQ1b mAb stained the whole cell surface of cerebellar granule cells, but not that of Purkinje cells. Therefore, the clinical symptoms of Miller-Fisher syndrome, such as cerebellar-like ataxia, may be explained by the inhibitory effects of anti-GQ1b antibodies on VDCC current in cerebellar granule cells.


Assuntos
Autoanticorpos/farmacologia , Canais de Cálcio/metabolismo , Córtex Cerebelar/metabolismo , Gangliosídeos/imunologia , Imunoglobulina M/metabolismo , Neurônios/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/imunologia , Animais , Animais Recém-Nascidos , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/imunologia , Células Cultivadas , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/imunologia , Técnicas de Cocultura , Ativação do Canal Iônico/efeitos dos fármacos , Ativação do Canal Iônico/imunologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/imunologia , Síndrome de Miller Fisher/imunologia , Síndrome de Miller Fisher/fisiopatologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/imunologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/imunologia , Músculo Esquelético/inervação , Neurônios/efeitos dos fármacos , Neurônios/imunologia , Técnicas de Patch-Clamp , Ratos , Ratos Wistar
12.
J Nippon Med Sch ; 74(1): 45-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17384477

RESUMO

Posterior capsule opacification (PCO) remains a common complication of modern cataract surgery, although both modification of materials used and changes in the intraocular lens (IOL) optic edge design have helped to decrease its incidence slightly. Recently, various kinds of quantitative methods have been developed for measuring PCO. The purpose of this study was to compare the quantitative analysis of PCO between different types of IOL designs. Patients enrolled in the study had age-related cataract and underwent uneventful cataract surgery and implantation of either the AcrySof MA30BA (Alcon) or the Sensor AR40e (AMO), which are differently designed hydrophobic acrylic IOLs with a sharp-edged optic design. Postoperative examination was performed at 6 months. Retroillumination photographs of each eye were obtained, and the degree of PCO was assessed using the Evaluation of Posterior Capsule Opacification (EPCO) system. Grade 1 PCO was noted in both the MA30BA and the AR40e groups. There was no significant difference in the mean PCO score between the MA30BA and AR40e groups. Although the sharp-edged optic designs of both IOLs might similarly inhibit PCO at 6 months, a long-term follow-up period is needed to determine if any PCO differences occur between these 2 hydrophobic acrylic IOLs.


Assuntos
Acrilatos , Catarata/diagnóstico , Catarata/etiologia , Técnicas de Diagnóstico Oftalmológico , Cápsula do Cristalino , Lentes Intraoculares/efeitos adversos , Idoso , Catarata/prevenção & controle , Extração de Catarata/efeitos adversos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Implante de Lente Intraocular/efeitos adversos , Desenho de Prótese
13.
Exp Neurol ; 200(1): 50-5, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16500643

RESUMO

Campylobacteriosis is frequently associated with Guillain-Barré syndrome. Poultry are frequently highly colonized with Campylobacter jejuni and are a major foodborne vehicle for campylobacteriosis. In this study, high titer anti-GM1 antibodies were found in the serum of a laboratory worker who developed campylobacteriosis. The microbiologically confirmed strain VLA2/18 (non-serotyped) was isolated from the worker and subsequently inoculated into chickens, resulting in high titers of serum antibodies to GM1. However, none of the immunized chickens in our study showed any noticeable neurological symptoms, such as paralysis or cramping. High titer anti-GM1 antibodies in chicken and human sera strongly inhibited spontaneous muscle action potential in an in vitro system of spinal cord and muscle cell co-culture. In addition, infection of chickens with C. jejuni strains 81116 (HS6) and 99/419 (HS21) or immunization with purified GM1, GM2, and GM3 resulted in elevation of serum anti-ganglioside antibodies with an inhibitory effect on spontaneous muscle action potential. Immunoabsorption studies demonstrated that this inhibitory activity is due to anti-ganglioside antibodies. On the other hand, anti-GM1 is the only specific human serum antibody to induce an inhibitory effect on neuromuscular junctions. Chicken anti-GM1 antibodies showed a strong inhibitory effect, but anti-GM2 and -GM3 had weaker activities. Taken together, our data suggest that campylobacteriosis in chickens may provide a strong link between infection and the development of anti-ganglioside antibody-mediated peripheral nerve dysfunctions.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Campylobacter/imunologia , Campylobacter jejuni/imunologia , Gangliosídeos/imunologia , Doenças das Aves Domésticas/imunologia , Potenciais de Ação/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Infecções por Campylobacter/prevenção & controle , Campylobacter jejuni/isolamento & purificação , Galinhas , Técnicas de Cocultura , Humanos , Doenças das Aves Domésticas/prevenção & controle , Ratos , Especificidade da Espécie
14.
J Neurosci Res ; 83(2): 274-84, 2006 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16342208

RESUMO

Recently we have reported cases of demyelinating inflammatory neuropathy showing elevated titers of anti-GD3 antibodies, which occurs rarely in Guillain-Barré syndrome. To examine the correlation between the anti-GD3 antibody titer and Campylobacter jejuni infection, we sensitized female Lewis rats with lipopolysaccharides (LPSs) from serotype HS19 of C. jejuni and examined changes in nerve conduction velocity and nerve conduction block (P/D ratio). After 16 weeks of sensitization, animals revealed decreases of nerve conduction velocity and conduction block (P/D ratio) and high titer of anti-GD3 antibodies. These anti-GD3 antibodies also blocked transmission in neuromuscular junctions of spinal cord-muscle cells cocultures. The GD3 epitope was verified to be located on the Schwann cell surface and nodes of Ranvier in rat sciatic nerve. To determine the target epitope for GD3 antibodies in causing nerve dysfunction, the LPS fraction containing the GD3 epitope was purified from the total LPS by using an anti-GD3 monoclonal antibody-immobilized affinity column. Subsequently, chemical analysis of the oligosaccharide portion was performed and confirmed the presence of a GD3-like epitope as having the following tetrasaccharide structure: NeuAcalpha2-8NeuAc2-3Galbeta1-4Hep. Our data thus support the possibility of a contribution of GD3 mimicry as a potential pathogenic mechanism of peripheral nerve dysfunction.


Assuntos
Formação de Anticorpos/fisiologia , Campylobacter jejuni/imunologia , Gangliosídeos/imunologia , Lipopolissacarídeos/administração & dosagem , Mimetismo Molecular/fisiologia , Ratos Endogâmicos Lew/imunologia , Animais , Campylobacter jejuni/química , Cromatografia em Camada Fina/métodos , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/fisiopatologia , Estimulação Elétrica/métodos , Eletromiografia/métodos , Epitopos , Potenciais Evocados/fisiologia , Potenciais Evocados/efeitos da radiação , Feminino , Imunofluorescência/métodos , Humanos , Imunização/métodos , Imunoglobulina G/metabolismo , Técnicas de Imunoadsorção , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Inflamação/fisiopatologia , Condução Nervosa/fisiologia , Proteínas de Neurofilamentos/metabolismo , Ratos , Tempo de Reação/fisiologia , Tempo de Reação/efeitos da radiação , Fatores de Tempo , Titulometria/métodos
15.
Brain Res ; 1034(1-2): 62-70, 2005 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-15713260

RESUMO

This study investigated the effects of the calcium channel blockers nicardipine, calcicludine, omega-conotoxin GVIA, omega-agatoxin IVA, SNX-482, and NiCl on spontaneous muscle action potential of a rat spinal cord-muscle co-culture system. Spontaneous muscle action potential of the innervated muscle cells was blocked by d-tubocurarine (1 microM), but was not significantly affected by the L-type channel blocker nicardipine (100 nM). The neuronal L-type calcium channel blocker, calcicludine (50 and 100 nM), also had no effect on the frequency of spontaneous muscle action potential. However, nicardipine (100 nM) and calcicludine (100 nM) significantly increased the amplitude of muscle action potential. Application of the N-type calcium channel blocker, omega-conotoxin GVIA (50 and 100 nM), and the P/Q-type calcium channel blocker, omega-agatoxin IVA (10, 30, 50, and 100 nM), blocked the frequency and amplitude of spontaneous muscle action potential of the spinal cord-muscle co-cultured cells. In contrast, spontaneous muscle action potential was not affected by the R-type calcium channel blockers SNX-482 (100 nM) or NiCl (500 nM). These results indicate that blockers of N- and P/Q-type voltage-dependent calcium channels inhibit transmitter release at neuromuscular junctions in the rat spinal cord-muscle co-culture system.


Assuntos
Potenciais de Ação/fisiologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Músculo Esquelético/inervação , Junção Neuromuscular/fisiologia , Medula Espinal/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio Tipo N/efeitos dos fármacos , Canais de Cálcio Tipo N/metabolismo , Canais de Cálcio Tipo P/efeitos dos fármacos , Canais de Cálcio Tipo P/metabolismo , Canais de Cálcio Tipo Q/efeitos dos fármacos , Canais de Cálcio Tipo Q/metabolismo , Células Cultivadas , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Feminino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Junção Neuromuscular/efeitos dos fármacos , Fármacos Neuromusculares não Despolarizantes/farmacologia , Ratos , Ratos Wistar , Medula Espinal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Tubocurarina/farmacologia
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