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1.
Aliment Pharmacol Ther ; 47(1): 104-113, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29035002

RESUMO

BACKGROUND: With the development of direct-acting anti-virals (DAAs), almost all patients with chronic hepatitis C virus (HCV) infection can achieve sustained viral response (SVR). AIM: To evaluate the short-term risk of HCC among patients with SVR by DAAs, including those with cirrhosis or previous HCC. METHODS: This large-scale, multicentre cohort study included 1,675 consecutive patients who achieved SVR by treatment with interferon-free sofosbuvir-based regimens, divided into groups with (n = 152) or without previous HCC (n = 1,523). The Kaplan-Meier method and Cox proportional hazard analysis were used to calculate the cumulative HCC incidence and related factors of HCC. RESULTS: During the follow-up period (median: 17 months), 46 (2.7%) patients developed HCC. The 1-year cumulative rates of de novo HCC were 0.4% and 4.9% for the noncirrhosis and cirrhosis groups respectively (log-rank test: P < 0.001). For cirrhotic patients, serum α-fetoprotein level at the end of treatment (EOT-AFP) was the strongest predictor of de novo HCC. The 1-year cumulative de novo HCC rates were 1.4% and 13.1% in the EOT-AFP < 9.0 ng/mL and ≥ 9.0 ng/mL groups (cut-off value) respectively (log-rank test: P < 0.001). The 1-year cumulative rates of HCC recurrence were 6.5% and 23.1% for the noncirrhosis and cirrhosis groups respectively (log-rank test: P = 0.023). For cirrhotic patients, previous HCC characteristics were significantly associated with HCC recurrence. In contrast, sex, age and metabolic features did not influence de novo HCC or recurrence. CONCLUSIONS: For cirrhotic patients after elimination of HCV, serum EOT-AFP level and previous HCC characteristics would be useful markers for predicting de novo HCC or recurrence.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Hepacivirus/efeitos dos fármacos , Humanos , Incidência , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Fatores de Risco , Adulto Jovem , alfa-Fetoproteínas/análise
2.
J Viral Hepat ; 22(12): 992-1001, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26075320

RESUMO

Favourable efficacy and safety profiles for simeprevir in combination with pegylated interferon alpha (PEG-IFNα) and ribavirin (triple therapy) have been shown in clinical trials. This study was carried out to evaluate the effectiveness of simeprevir-based triple therapy for patients with prior telaprevir treatment failure. This multicentre, observational cohort consisted of 345 consecutive Japanese patients infected with HCV genotype 1b, including 20 who had experienced telaprevir-based triple therapy. Amino acid substitutions in the NS3/4A region were identified by direct sequencing at the time of relapse or breakthrough in treatment with telaprevir and at the initiation of treatment with simeprevir. Patients were stratified according to prior response to PEG-IFNα and ribavirin. Of the 20 patients with telaprevir treatment failure, 10 (50.0%) achieved sustained virological response at week 12 after the end of treatment (SVR12). For patients treatment naïve [3/4 (75.0%)] or with prior relapse [1/1 (100%)] or partial response [5/6 (83.3%)] to PEG-IFNα and ribavirin, almost all achieved SVR12, mainly because of the improvement of treatment adherence, especially to direct-acting antiviral agent and ribavirin. However, of the nine patients with prior null response to PEG-IFNα and ribavirin, only one (11.1%) achieved SVR12, despite all having received an adequate treatment dosage, and five (55.6%) achieved rapid virological response. The treatment outcome of simeprevir-based triple therapy for HCV genotype 1b patients with prior telaprevir failure depended on the prior response to PEG-IFNα and ribavirin. For patients with prior null response to PEG-IFNα and ribavirin, retreatment with simeprevir-based triple therapy is not a useful option.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Simeprevir/uso terapêutico , Idoso , Antivirais/uso terapêutico , Proteínas de Transporte/genética , Quimioterapia Combinada , Feminino , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Humanos , Interferon alfa-2 , Peptídeos e Proteínas de Sinalização Intracelular , Japão , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Recidiva , Simeprevir/efeitos adversos , Falha de Tratamento , Proteínas não Estruturais Virais/genética
3.
Aliment Pharmacol Ther ; 38(9): 1076-85, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24099469

RESUMO

BACKGROUND: Antiviral treatment is recommended for chronic hepatitis C patients with advanced fibrosis to reduce and prevent cirrhosis-related complications. AIM: To evaluate the efficacy and safety of telaprevir (TVR)-based triple therapy for patients with advanced fibrosis in a clinical practice setting. METHODS: This prospective, multicentre study consisted of 102 patients with advanced fibrosis (METAVIR score F3-4) who were infected with HCV genotype 1b. All received 12 weeks of TVR in combination with 24 weeks of pegylated interferon (PEG-IFN) α2b and ribavirin (RBV). RESULTS: The sustained virological response (SVR) rate was 69.6% (71 of 102). Notably, for treatment-naïve and prior relapse patients the SVR rate was over 80%. Previous treatment response, interleukin 28B polymorphism (rs8099917) and rapid virological response (undetectable HCV RNA at week 4) were independently associated with SVR. To achieve SVR, an adequate dosage of PEG-IFNα2b (≥1.2 µg/kg/week) and RBV (≥7.5 mg/kg/day) is preferable; however, the mean weight-adjusted TVR dosage had little impact on treatment outcome. Although severe blood cytopaenia and a dermatological disorder were frequently found, the rate of discontinuation due to adverse effects was 12.7%. The inosine triphosphatase CC allele (rs1127354) was independently associated with the development of severe anaemia, and lower serum albumin level (<35 g/L) was associated with the occurrence of infection. CONCLUSIONS: The great gain in the SVR rate by telaprevir-based triple therapy offsets the problems with adverse effects; thus, it should be considered as a potent treatment protocol for patients with advanced fibrosis, especially for those with treatment-naïve and prior relapse.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Idoso , Anemia/epidemiologia , Anemia/etiologia , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/fisiopatologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Interferon-alfa/uso terapêutico , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/uso terapêutico , Estudos Prospectivos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Recidiva , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico , Resultado do Tratamento
4.
Pharmacopsychiatry ; 46(7): 225-60, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23975855

RESUMO

INTRODUCTION: Social anxiety disorder is believed to be a stress-induced disease. Although it can be inferred from the symptoms during attacks that there exists some abnormality of autonomic nervous system in any of the stress systems in social anxiety disorder, little evidence has been reported. This study focused on comparing the reactivity of 2 stress systems, the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis in patients with social anxiety disorder. METHODS: 32 patients with the generalized type of social anxiety disorder were compared with 80 age- and gender-matched controls. We collected saliva samples from patients and controls before and after electrical stimulation to measure the concentrations of salivary alpha-amylase (sAA) and salivary cortisol. Profile of Mood State (POMS) and State-Trait Anxiety Inventory (STAI) scores and Heart Rate Variability (HRV) were also determined following stimulation. RESULTS: SAA in patients displayed a significantly higher level at baseline and a significantly larger response to electrical stimulation as compared to controls, whereas no group differences were seen in any HRV. Neither within-subject nor group differences were seen in salivary cortisol levels. CONCLUSIONS: These results suggest that SAD patients displayed enhanced ANS (but not HPA axis) activity vs. healthy controls.


Assuntos
Transtornos de Ansiedade/metabolismo , Hidrocortisona/metabolismo , alfa-Amilases/metabolismo , Adulto , Transtornos de Ansiedade/enzimologia , Transtornos de Ansiedade/fisiopatologia , Sistema Nervoso Autônomo/fisiopatologia , Estudos de Casos e Controles , Estimulação Elétrica , Feminino , Frequência Cardíaca/fisiologia , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Nervo Mediano/fisiologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Saliva/metabolismo
5.
Antiviral Res ; 74(1): 1-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17303260

RESUMO

We have investigated the inhibitory effect of trans-cinnamaldehyde (CA), one of the principal constituents of essential oil derived from Cinnamomi cortex, on the growth of influenza A/PR/8 virus in vitro and in vivo. When 1-h drug treatment was initiated at various times post-infection (p.i.) in Madin-Darby canine kidney cells using a fixed dose of CA (40 microM), the maximum inhibitory effect (29.7% virus yield of control) was obtained when drug treatment was started at 3h p.i. Under the same treatment schedule, CA inhibited the virus growth in a dose-dependent manner (20-200 microM), and, at 200 microM, the virus yield was reduced to an undetectable level. RT-PCR and SDS-PAGE analyses showed that CA inhibited viral protein synthesis at the post-transcriptional level. In mice infected with the lung-adapted PR-8 virus, inhalation (50mg/cage/day) and nasal inoculation (250 microg/mouse/day) of CA significantly increased survival rates on the 8 days to 100% and 70%, respectively, in contrast to a survival rate of 20% in the untreated control group. Importantly, inhalation of CA caused virus yield reduction by 1 log in bronchoalveolar lavage fluid on day 6 after infection, compared with that of the untreated control group. These findings might provide further support to the empirical indication of Cinnamomi cortex-containing Kampo medicines for acute respiratory infectious diseases.


Assuntos
Acroleína/análogos & derivados , Antivirais/farmacologia , Cinnamomum/química , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Acroleína/administração & dosagem , Acroleína/química , Acroleína/farmacologia , Administração por Inalação , Administração Intranasal , Animais , Antivirais/administração & dosagem , Antivirais/química , Líquido da Lavagem Broncoalveolar/virologia , Linhagem Celular , Embrião de Galinha , Relação Dose-Resposta a Droga , Feminino , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/crescimento & desenvolvimento , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/crescimento & desenvolvimento , Camundongos , Testes de Sensibilidade Microbiana , Infecções por Orthomyxoviridae/virologia , Proteínas Virais/biossíntese , Proteínas Virais/efeitos dos fármacos
6.
Phys Med Biol ; 48(15): 2269-81, 2003 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-12953897

RESUMO

Washout of 10C and 11C implanted by radioactive beams in brain and thigh muscle of rabbits was studied. The biological washout effect in a living body is important in the range verification system or three-dimensional volume imaging in heavy ion therapy. Positron emitter beams were implanted in the rabbit and the annihilation gamma-rays were measured by an in situ positron camera which consisted of a pair of scintillation cameras set on either side of the target. The ROI (region of interest) was set as a two-dimensional position distribution and the time-activity curve of the ROI was measured. Experiments were done under two conditions: live and dead. By comparing the two sets of measurement data, it was deduced that there are at least three components in the washout process. Time-activity curves of both brain and thigh muscle were clearly explained by the three-component model analysis. The three components ratios (and washout half-lives) were 35% (2.0 s), 30% (140 s) and 35% (10 191 s) for brain and 30% (10 s), 19% (195 s) and 52% (3175 s) for thigh muscle. The washout effect must be taken into account for the verification of treatment plans by means of positron camera measurements.


Assuntos
Encéfalo/metabolismo , Radioisótopos de Carbono/metabolismo , Transferência Linear de Energia/fisiologia , Músculo Esquelético/metabolismo , Mudanças Depois da Morte , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Animais , Simulação por Computador , Meia-Vida , Taxa de Depuração Metabólica/fisiologia , Modelos Biológicos , Coelhos , Doses de Radiação
7.
J Synchrotron Radiat ; 8(Pt 2): 334-5, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11512771

RESUMO

A novel two dimensional imaging technique of the chemical bonding state was developed by combining the extended X-ray emission fine structure method with an electron probe X-ray microanalyzer mapping technology. With this method, chemical state images of some aluminum standard samples were obtained. It was confirmed that the obtained images provide correct information of chemical states.

8.
Int J Urol ; 8(5): 257-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11328430

RESUMO

A 52-year-old unmarried bag craftsman was admitted to East Tokyo Metropolitan Hospital because of a large scrotal hematoma. He had accidentally hit his right testis against the edge of a desk early the previous morning. He had resected his right testis with scissors to release from severe pain 30 min after the accident. He had sutured the scrotal incision with two stitches of string by himself. At the emergency operation 36 h after the self-mutilation, we removed a hematoma weighing 283 g and ligated the cut end of the right spermatic cord after adequate debridement. He was diagnosed by a psychiatrist as having slightly low intelligence without psychotic disorder or drug abuse.


Assuntos
Automutilação/etiologia , Testículo/lesões , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Esquizofrenia
9.
Biosci Biotechnol Biochem ; 64(6): 1230-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10923795

RESUMO

Penicillum sp. 40, which can grow in an extremely acidic medium at pH 2.0 was screened from an acidic soil. This fungus produces xylanases when grown in a medium containing xylan as a sole carbon source. A major xylanase was purified from the culture supernatant of Penicillium sp. 40 and designated XynA. The molecular mass of XynA was estimated to be 25,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. XynA has an optimum pH at 2.0 and is stable in pH 2.0-5.0. Western blot analysis using anit-XynA antibody showed that XynA was induced by xylan and repressed by glucose. Also, its production was increased by an acidic medium. The gene encoding XynA (xynA) was isolated from the genomic library of Penicillium sp. 40. The structural part of xynA was found to be 721 bp. The nucleotide sequence of cDNA amplified by RT-PCR showed that the open reading frame of xynA was interrupted by a single intron which was 58 bp in size and encoded 221 amino acids. Direct N-terminal amino acid sequencing showed that the precursor of XynA had a signal peptide composed of 31 amino acids. The molecular mass caliculated from the deduced amino acid sequence of XynA is 20,713. This is lower than that estimated by gel electrophoresis, suggesting that XynA is a glycoprotein. The predicted amino acid sequence of XynA has strong similarity to other family xylanases from fungi.


Assuntos
Penicillium/enzimologia , Penicillium/genética , Xilosidases/genética , Xilosidases/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , DNA Fúngico/genética , Endo-1,4-beta-Xilanases , Estabilidade Enzimática , Genes Fúngicos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Xilosidases/química
10.
J Vet Med Sci ; 62(7): 797-800, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10945305

RESUMO

The 16S rRNA gene of the SMR strain of cilia-associated respiratory (CAR) bacillus, which was isolated from a spontaneously infected rat at our institute, was sequenced. Its 1,521 nucleotides were determined. On the basis of the results of the sequence analysis, the SMR strain was found to be most closely related to members of the Flavobacter/Flexibacter group. This sequence was compared with the previously determined 16S rRNA gene sequences (rat-origin: three; mouse-origin: one; rabbit-origin: one) of CAR bacillus isolates. The SMR strain showed the highest sequence similarity (99.9%) to the rat-origin CARB-NIH strain (Schoeb et al., 1993), and it was concluded that the strains are identical.


Assuntos
Bacillus/classificação , DNA Ribossômico/genética , Infecções por Bactérias Gram-Negativas/veterinária , RNA Ribossômico 16S/genética , Doenças dos Roedores/microbiologia , Animais , Animais de Laboratório , Bacillus/genética , Bacillus/isolamento & purificação , Sequência de Bases , Cílios/microbiologia , Primers do DNA , Infecções por Bactérias Gram-Negativas/microbiologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Ratos , Mucosa Respiratória/microbiologia , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
11.
Intern Med ; 39(5): 412-5, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830185

RESUMO

We report a 50-year-old man who developed therapy-related myelodysplastic syndrome after treatment with etoposide-including chemotherapy for extratesticular germ cell tumor. Chromosomal analysis showed inversion 11 (p15q22) translocation. Reverse transcriptase-polymerase chain reaction amplification of patient RNA showed a fusion transcript of nucleoporin gene NUP98, and putative DEAD-box RNA helicase gene DDX10. NUP98 is implicated in the transformation through aberrant nucleocytoplasmic transport. DDX10 is suggested to be involved in ribosome assembly. The NUP98-DDX10 fusion transcript may promote the development of secondary hematological malignancies caused by DNA-topoisomerase II inhibitors through aberrant nucleocytoplasmic transport and/or alteration in ribosome assembly.


Assuntos
Fusão Gênica Artificial , Inversão Cromossômica , Cromossomos Humanos Par 11 , Proteínas de Membrana/genética , Síndromes Mielodisplásicas/genética , Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas Nucleares/genética , RNA Helicases/genética , Antineoplásicos Fitogênicos/efeitos adversos , Citogenética , Inibidores Enzimáticos/efeitos adversos , Etoposídeo/efeitos adversos , Germinoma/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/etiologia , Inibidores da Síntese de Ácido Nucleico/efeitos adversos , Neoplasias Retroperitoneais/tratamento farmacológico , Inibidores da Topoisomerase II , Translocação Genética
12.
Otolaryngol Head Neck Surg ; 122(3): 425-33, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10699822

RESUMO

Using an animal model, we have studied the response of the auditory brain stem to cochlear implantation and the effect of intracochlear factors on this response. Neonatally, pharmacologically deafened cats (100 to more than 180 days old) were implanted with a 4-electrode array in both cochleas. Then, the left cochlea of each cat was electrically stimulated for total periods of up to 1000 hours. After a terminal (14)C-2-deoxyglucose (2DG) experiment, the fraction of the right inferior colliculus with a significant accumulation of 2DG label was calculated. Using 3-dimensional computer-aided reconstruction, we examined the cochleas of these animals for spiral ganglion cell (SGC) survival and intracochlear factors such as electrode positions, degeneration of the organ of Corti, and the degree of fibrosis of the scala tympani. The distribution of each parameter was calculated along the organ of Corti from the basal end. There was a positive correlation between SGC survival and the level of fibrosis in the scala tympani, and a negative correlation between SGC survival and the degree of organ of Corti degeneration. Finally, there was a negative correlation between the 2DG-labeled inferior colliculus volume fraction and the degree of fibrosis, particularly in the 1-mm region nearest the pair of electrodes, and presumably in the basal turn.


Assuntos
Cóclea/fisiopatologia , Implante Coclear , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Complicações Pós-Operatórias/fisiopatologia , Gânglio Espiral da Cóclea/fisiopatologia , Animais , Autorradiografia , Glicemia/metabolismo , Tronco Encefálico/patologia , Tronco Encefálico/fisiopatologia , Gatos , Sobrevivência Celular/fisiologia , Cóclea/patologia , Eletrodos Implantados , Fibrose , Processamento de Imagem Assistida por Computador , Colículos Inferiores/patologia , Colículos Inferiores/fisiopatologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Órgão Espiral/patologia , Órgão Espiral/fisiopatologia , Complicações Pós-Operatórias/patologia , Gânglio Espiral da Cóclea/patologia
16.
Radiat Res ; 150(3): 304-15, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9728660

RESUMO

The late effects of heavy-ion irradiation on the spinal cord of the rat were investigated histologically and morphometrically. After a single exposure of each animal's lower thoracic and lumbar spinal cord to a carbon-ion beam, the animals were observed clinically for up to 69 weeks and their spinal cords were examined histologically after sacrifice. Paralysis of the hind limbs appeared from 16 to 20 weeks after irradiation with 20 Gy or more. The first histological change seen was vacuolization in the marginal white matter, which appeared 19 to 25 weeks after irradiation with more than 10 Gy. After irradiation with more than 15 Gy, bilateral destructive cavities occurred in the white matter, especially in the lateral tract. These histological changes were similar to those reported frequently for X irradiation. The mean cross-sectional area of the blood vessels in the irradiated spinal cord increased in a manner that was dependent on dose and was significantly larger 15 to 17 weeks after irradiation with 30 Gy. Reconstruction of small destructive lesions from serial sections consistently revealed dilated veins in the centers of these lesions. The effective dose that induces 50% incidence of hind-limb paralysis and destructive cavity formation (ED50) as determined using a curve-fitting method was 18.5 and 19.5 Gy, respectively, and the latent period was shorter than that for X irradiation.


Assuntos
Carbono , Lesões Experimentais por Radiação/patologia , Doenças da Medula Espinal/patologia , Medula Espinal/efeitos da radiação , Animais , Vasos Sanguíneos/patologia , Vasos Sanguíneos/efeitos da radiação , Relação Dose-Resposta à Radiação , Membro Posterior , Masculino , Bainha de Mielina/patologia , Bainha de Mielina/efeitos da radiação , Paralisia/etiologia , Ratos , Ratos Wistar , Organismos Livres de Patógenos Específicos , Medula Espinal/irrigação sanguínea , Medula Espinal/patologia , Fatores de Tempo , Vacúolos
17.
Acta Otolaryngol ; 118(3): 313-26, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9655204

RESUMO

The performance of cochlear implant patients may be related to intracochlear, histopathological factors. We have performed detailed post-mortem examinations of five human, implanted cochleas and for each electrode correlated the psychophysical threshold, comfortable level and dynamic range with spiral ganglion cell survival, presence of fibrous tissue and/or new bone, and distance between the centers of the electrode bands and Rosenthal's canal. The psychophysical parameters were strongly interrelated. Threshold and comfort levels correlated with the distance between the electrodes and Rosenthal's canal. Threshold levels also correlated with the presence of intracochlear fibrous tissue and new bone, especially with the former. The dynamic range showed a negative correlation with intracochlear pathology, especially with new bone. Comfort levels and dynamic range were related to spiral ganglion cell survival. The distance between the electrodes and the modiolus increased with increasing levels of fibrous tissue and new bone. Spiral ganglion cell survival was decreased with increasing levels of fibrous tissue and new bone.


Assuntos
Cóclea/patologia , Implantes Cocleares , Transtornos da Audição/patologia , Processamento de Imagem Assistida por Computador , Osso Temporal/patologia , Adulto , Idoso , Sobrevivência Celular , Cóclea/anatomia & histologia , Implantes Cocleares/efeitos adversos , Feminino , Transtornos da Audição/fisiopatologia , Humanos , Masculino , Órgão Espiral/patologia , Psicoacústica , Análise de Regressão , Gânglio Espiral da Cóclea/anatomia & histologia , Gânglio Espiral da Cóclea/patologia , Estatísticas não Paramétricas
18.
Laryngoscope ; 108(5): 687-95, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9591547

RESUMO

We have studied spiral ganglion cell (SGC) survival and soma size in neonatally pharmacologically deafened kittens. They were implanted with a four-electrode array in the left cochlea at 100 to 180 or more days of age. Eight animals were chronically stimulated approximately 1000 hours over approximately 60 days with charge-balanced, biphasic current pulses; three were unstimulated controls. Using three-dimensional computer-aided reconstruction of the cochlea, the SGC position and cross-sectional area were stored. SGC position was mapped to the organ of Corti by perpendicular projections, starting from the basal end. The basal region of the cochlea was divided into three 4-mm segments. SGC survival (number per 0.1 mm of the length of the organ of Corti) and soma size for stimulated cochleae were compared statistically with implanted but unstimulated cochleae. There was no evidence of an effect of electrical stimulation on SGC survival under this protocol and with this duration. On the other hand, the cell size on the stimulated side was significantly larger than the control side in the middle segment (4 to 8 mm from the basal end). SGCs undergo a reduction in size after prolonged auditory deprivation; however, these changes may be partially moderated after chronic intracochlear electrical stimulation.


Assuntos
Surdez/fisiopatologia , Gânglio Espiral da Cóclea/patologia , Gânglio Espiral da Cóclea/fisiopatologia , Animais , Gatos , Tamanho Celular , Sobrevivência Celular , Cóclea/fisiopatologia , Estimulação Elétrica , Eletrodos , Neurônios/patologia , Neurônios/fisiologia , Órgão Espiral/fisiopatologia
19.
Genetics ; 148(2): 867-76, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9504932

RESUMO

The polyubiquitin gene is an evolutionarily conserved eukaryotic gene, encoding tandemly repeated multiple ubiquitins, and is considered to be subject to concerted evolution. Here, we present the nucleotide sequences of new alleles of the polyubiquitin gene UbC in humans and CHUB2 in Chinese hamster, which encode a different number of ubiquitin units from those of previously reported genes. And we analyze the concerted evolution of these genes on the basis of their orthologous relationship. That the mean of the synonymous sequence difference Ks which is defined as the number of synonymous substitution relative to the total number of synonymous sites, within the UbC and CHUB2 genes (0.192 +/- 0.096) is significantly less than Ks between these genes (0.602 +/- 0.057) provides direct evidence for concerted evolution. Moreover, it also appears that concerted evolutionary events have been much more frequent in CHUB2 than in UbC, because Ks within CHUB2 (0.022 +/- 0.018) is much less than that within UbC (0.362 +/- 0.192). By a numerical simulation, postulating that the major mechanism of concerted evolution in polyubiquitin genes is unequal crossing over, we estimated the frequency of concerted evolutionary events of CHUB2 at 3.3 x 10(-5) per year and that of UbC at no more than 5.0 x 10(-7) per year.


Assuntos
Biopolímeros/genética , Repetições Minissatélites/genética , Ubiquitinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Simulação por Computador , Cricetinae , Cricetulus , Troca Genética/genética , Análise Mutacional de DNA , Bases de Dados Factuais , Evolução Molecular , Células HeLa , Humanos , Modelos Genéticos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Poliubiquitina , Análise de Sequência de DNA
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