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1.
Opt Express ; 24(23): 26956-26971, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27857423

RESUMO

The use of resonant whispering gallery modes (WGMs) for sensing exhibits various drawbacks and critical points related to the microsphere and tapered optical fiber fabrication tolerance. The uncertainty on the fiber taper and microsphere geometry or the gap between the microsphere and the fiber taper can complicate or limit the actual use of these devices for sensing, requiring peculiar calibration of the WGM based sensing set-up. An alternative double-step approach is proposed in this paper. In particular, the geometrical parameters of the set-up are recovered preliminarily and then the rare earth parameters are recovered via simple transmittance/gain measurements. The method is based on a refined electromagnetic model of the device suitably integrated with a particle swarm optimization (PSO) approach. The percent errors made on the up-conversion coefficients Cup and C3 are extremely low, being 0.75%, 0.05%, respectively. The procedure is very robust. It can be applied more in general, allowing the sensing of other physical parameters via simple transmittance measurements instead of wavelength shift ones, in both microsphere and microbubble based set-up.

2.
Pharmacopsychiatry ; 49(3): 97-106, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27074948

RESUMO

INTRODUCTION: No meta-analysis has evaluated azapirones (serotonin1A receptor partial agonists) as anxiolytics for attention deficit hyperactivity disorder (ADHD). METHODS: Randomized controlled trials (RCTs) and single-arm trials published before October 27, 2015 were retrieved from major healthcare databases and clinical trial registries. Relative risk and 95% confidence intervals were calculated. RESULTS: 5 RCTs (n=429) and 3 single-arm studies (n=70) were identified. 3 RCTs compared buspirone vs. methylphenidate in children/adolescents, one buspirone patches vs. placebo patches in children/adolescents, and one atomoxetine plus buspirone vs. atomoxetine vs. placebo in adults. The single-arm studies were buspirone trails in children/adolescents. All-cause discontinuation rates and adverse events did not differ between pooled buspirone and methylphenidate groups. No other meta-analyses of buspirone efficacy and safety vs. comparators were conducted due to insufficient data. 2 RCTs found no significant differences in parent and teacher ADHD-Rating Scale total scores between buspirone and methylphenidate, while one reported that methylphenidate improved parent and teacher ADHD-RS total scores vs. buspirone. DISCUSSION: It remains unclear whether buspirone use has benefit for ADHD patients and therefore further evidence is needed for better clinical use of buspirone in patients with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Buspirona/uso terapêutico , Agonistas do Receptor de Serotonina/uso terapêutico , Buspirona/química , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Pharmacopsychiatry ; 48(1): 30-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25321187

RESUMO

INTRODUCTION: No comprehensive meta-analysis has been performed concerning the efficacy and tolerability of adjunctive therapy with histamine-2 receptor antagonists (H2R-ANTs) in schizophrenia patients who were treated with antipsychotics. METHODS: Risk ratios, standardized mean differences (SMD), and 95% confidence intervals were calculated. RESULTS: We included 8 double-blinded, randomized placebo-controlled trials (RCTs) (n=418) that met the inclusion criteria (famotidine: N=3, n=74; nizatidine: N=4, n=292; ranitidine: N=1, n=52). Pooled H2R-ANTs were not different from placebo with regard to reduction in overall symptoms and body weight. However, pooled H2R-ANTs resulted in lower body mass index (BMI) than placebo (SMD=-0.68). Moreover, nizatidine was associated with an increase in plasma leptin levels (SMD=-1.14). There were no significant differences in the discontinuation rates due to all-cause, side effects, and inefficacy between pooled H2R-ANTs and placebo. However, nizatidine produced more depression and dry mouth than placebo. DISCUSSION: H2R-ANT adjunctive therapy did not improve overall symptoms. To clarify the opposite results between body weight and BMI, future research should investigate long-term efficacy and generate more safety data by using larger samples.


Assuntos
Antipsicóticos/uso terapêutico , Antagonistas dos Receptores Histamínicos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Esquizofrenia/tratamento farmacológico , Peso Corporal/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
4.
Psychol Med ; 44(11): 2255-69, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24262766

RESUMO

BACKGROUND: A meta-analysis of the serotonin1A (5-HT1A) receptor partial agonist of the azapirone class as an anxiolytic drug for the treatment of major depressive disorder (MDD) has not previously been reported. METHOD: We carried out a systematic review of the literature available in PubMed, the Cochrane Library database and PsycINFO up to 12 October 2013, and conducted a meta-analysis of randomized controlled trials (RCTs) comparing 5-HT1A agonists with placebo and RCTs of 5-HT1A agonist augmentation therapies for MDD treatment. We calculated the risk ratio (RR), number needed to treat (NNT)/number needed to harm (NNH) and 95% confidence intervals (CIs). RESULTS: Fifteen RCTs comparing 5-HT1A agonists with placebo (total n = 2469, four studies with buspirone, seven with gepirone, three with ipsapirone and one with zalospirone) were identified. Pooled 5-HT1A agonists had significantly more responders (RR 0.74, 95% CI 0.65-083, p < 0.00001, NNT = 6, 12 trials, n = 1816) than placebo. Pooled 5-HT1A agonists were superior to placebo in discontinuation due to inefficacy (RR 0.49, p = 0.02, NNH = 16, p = 0.03, 10 trials, n = 1494) but were inferior to placebo in discontinuation due to side-effects (RR 1.88, p < 0.0001, NNH = 17, p = 0.001, 13 trials, n = 2196). However, all-cause discontinuation was similar in both groups (RR 0.99, p = 0.85, 14 trials, n = 2402). Four 5-HT1A agonist augmentation studies were identified (total n = 365, three buspirone studies and one tandospirone study). There were no statistically significant effects of 5-HT1A agonist augmentation therapies on response rate (RR 0.98, p = 0.85, four trials, n = 341). 5-HT1A agonist-related side-effects including gastrointestinal symptoms, dizziness, insomnia, palpitation, paresthesia and sweating were greater than with placebo (p < 0.00001 to p = 0.03). CONCLUSIONS: Our results suggest that 5-HT1A agonist has a more beneficial effect on MDD than placebo, but has several side-effects.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Agonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Humanos , Agonistas do Receptor 5-HT1 de Serotonina/efeitos adversos
5.
Mol Psychiatry ; 18(1): 53-66, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22124274

RESUMO

Few controlled trials compared second-generation antipsychotics (SGAs) with first-generation antipsychotics (FGAs) regarding relapse prevention in schizophrenia. We conducted a systematic review/meta-analysis of randomized trials, lasting 6 months comparing SGAs with FGAs in schizophrenia. Primary outcome was study-defined relapse; secondary outcomes included relapse at 3, 6 and 12 months; treatment failure; hospitalization; and dropout owing to any cause, non-adherence and intolerability. Pooled relative risk (RR) (±95% confidence intervals (CIs)) was calculated using random-effects model, with numbers-needed-to-treat (NNT) calculations where appropriate. Across 23 studies (n=4504, mean duration=61.9±22.4 weeks), none of the individual SGAs outperformed FGAs (mainly haloperidol) regarding study-defined relapse, except for isolated, single trial-based superiority, and except for risperidone's superiority at 3 and 6 months when requiring ≥3 trials. Grouped together, however, SGAs prevented relapse more than FGAs (29.0 versus 37.5%, RR=0.80, CI: 0.70-0.91, P=0.0007, I(2)=37%; NNT=17, CI: 10-50, P=0.003). SGAs were also superior regarding relapse at 3, 6 and 12 months (P=0.04, P<0.0001, P=0.0001), treatment failure (P=0.003) and hospitalization (P=0.004). SGAs showed trend-level superiority for dropout owing to intolerability (P=0.05). Superiority of SGAs regarding relapse was modest (NNT=17), but confirmed in double-blind trials, first- and multi-episode patients, using preferentially or exclusively raw or estimated relapse rates, and for different haloperidol equivalent comparator doses. There was no significant heterogeneity or publication bias. The relevance of the somewhat greater efficacy of SGAs over FGAs on several key outcomes depends on whether SGAs form a meaningful group and whether mid- or low-potency FGAs differ from haloperidol. Regardless, treatment selection needs to be individualized considering patient- and medication-related factors.


Assuntos
Antipsicóticos/classificação , Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/prevenção & controle , Bases de Dados Factuais/estatística & dados numéricos , Seguimentos , Humanos , Prevenção Secundária , Sensibilidade e Especificidade , Fatores de Tempo
6.
Mol Hum Reprod ; 17(4): 266-71, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21159741

RESUMO

Synaptonemal complex protein 3 (SYCP3) plays a critical role in homologous chromosome pairing and recombination in meiosis, and mice deficient in this gene show infertility in males and subfertility in females. The aim of our current study was to determine whether genetic alterations in the SYCP3 gene are associated with female infertility in humans. We examined sequence variations of the SYCP3 gene in genomic DNA from 88 Japanese women with unexplained infertility and 165 samples obtained from a fertile control group. Case-control study using seven tagging single nucleotide polymorphisms revealed no significant association between common SYCP3 variants and unexplained infertility. However, only infertile women were homozygous for the minor allele of a novel rare variant in the coding region, c.666A>G (222Q>Q). The minor allele frequency was significantly higher in the infertile cohort (P< 0.05). This variant is predicted to create a cryptic splice site, although the expression of a mini-gene harboring the variant in HeLa cells or mouse testis did not demonstrate any effects on gene splicing. Our current findings therefore suggest that the c.666A>G variant in the SYCP3 gene might possibly contribute to female infertility in humans, although larger studies are needed to assess the possible effects of SYCP3 gene variation on human female infertility.


Assuntos
Variação Genética , Infertilidade Feminina/genética , Proteínas Nucleares/genética , Adulto , Animais , Povo Asiático , Proteínas de Ciclo Celular , Células Cultivadas , Proteínas de Ligação a DNA , Feminino , Células HeLa , Humanos , Camundongos
7.
Int J Immunogenet ; 38(4): 287-93, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21382177

RESUMO

Systemic juvenile idiopathic arthritis (s-JIA) is a rare inflammatory disease classified as a subtype of chronic childhood arthritis, manifested by spiking fever, erythematous skin rash, pericarditis and hepatosplenomegaly. The genetic background underlying s-JIA remains poorly defined. To detect copy number variations, we performed single nucleotide polymorphism (SNP) array analysis in 50 patients with s-JIA. We found a 13-kb intragenic deletion of CASP10 in one patient. RT-PCR of the mRNA extracted from the patient's lymphoblastoid cells revealed that CASP10 mRNA was truncated. Sequencing the mRNA revealed that this deletion resulted in a frame shift with an early stop codon. CASP10 is known as a causative gene for autoimmune lymphoproliferative syndrome (ALPS) type IIa, another childhood syndrome of lymphadenopathy and splenomegaly associated with autoimmune haemolytic anaemia and thrombocytopenia. TCR αß(+) CD4/CD8 double-negative T cells in the peripheral blood as a diagnostic marker of ALPS were not high in this patient and lymphocyte apoptosis induced by anti-Fas antibody was normal, denying ALPS in the patient. The father and a sister of the patient showing no symptoms of ALPS or s-JIA, also had the same deletion. Furthermore, we found no other mutations of CASP10 in the other 49 s-JIA patients. These data suggest that the pathogenic significance of CASP10 mutations should be carefully evaluated in s-JIA or even ALPS type IIa in further studies.


Assuntos
Artrite Juvenil/genética , Caspase 10/genética , Éxons/genética , Deleção de Sequência/genética , Artrite Juvenil/imunologia , Artrite Juvenil/metabolismo , Sequência de Bases , Caspase 8/genética , Criança , Cromossomos Humanos Par 2 , Feminino , Ordem dos Genes , Estudo de Associação Genômica Ampla , Humanos , Dados de Sequência Molecular , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Alinhamento de Sequência , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
8.
J Hosp Infect ; 106(3): 594-599, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32866631

RESUMO

BACKGROUND: Scabies is a contagious dermatosis. The risk factors for its transmission remain unclear. A scabies outbreak, involving patients who were receiving chemotherapy for haematological malignancies, occurred at our hospital. METHODS: The outbreak population was analysed to determine whether the incidence of scabies was higher among contact patients receiving chemotherapy for haematological malignancies. RESULTS: A patient with crusted scabies was the index case, and 18 of 78 contact healthcare workers (HCWs) and 22 of 135 contact patients were diagnosed with classical scabies. Ten of 17 contact patients with haematological malignancies and 12 of 118 contact patients with other diseases were infected with scabies. The incidence rate was significantly higher among the patients with haematological malignancies (P<0.001). The patients with haematological malignancies had a significantly lower mean minimum neutrophil count than those with other diseases (1159/µL vs 3761/µL, P=0.0012). Most haematological patients did not require special nursing assistance, suggesting that the higher incidence of scabies among these patients resulted from their immunodeficiency rather than greater skin-to-skin contact with infected HCWs. CONCLUSION: Our study suggests that patients receiving chemotherapy for haematological malignancies are more susceptible to scabies than patients with other diseases, and require stricter protection.


Assuntos
Suscetibilidade a Doenças/induzido quimicamente , Tratamento Farmacológico , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Escabiose/etiologia , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Suscetibilidade a Doenças/parasitologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Pessoal de Saúde/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Humanos , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional/estatística & dados numéricos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Escabiose/epidemiologia , Escabiose/transmissão
9.
Genes Brain Behav ; 6(1): 107-12, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17233643

RESUMO

Recent investigations suggest that the AKT/glycogen synthase kinase 3 (GSK3) signaling cascade may be associated with the pathophysiology of schizophrenia and methamphetamine (METH) use disorder. One important molecule related to this cascade is beta-arrestin 2 (ARRB2). We therefore conducted a genetic case-control association analysis of the gene for ARRB2 with schizophrenia and METH use disorder in a Japanese population (547 people with schizophrenia, 177 with METH use disorder and 546 controls). A possible association of 'tag single nucleotide polymorphisms (SNPs)' was found in METH use disorder (rs1045280: P(genotype) = 0.0118, P(allele) = 0.00351; rs2036657: P(allele) = 0.0431; rs4790694: P(genotype) = 0.0167, P(allele) = 0.0202), but no association was found with schizophrenia. We also evaluated the gene-gene interactions among ARRB2, AKT1, and GSK3B, which we previously reported for each of these diseases. However, no interaction was seen in our samples. This is the first association analysis of ARRB2, and our results indicate that ARRB2 may play a role in the pathophysiology of METH use disorder.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/genética , Arrestinas/genética , Esquizofrenia/genética , Adulto , Transtornos Relacionados ao Uso de Anfetaminas/metabolismo , Arrestinas/metabolismo , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Metanfetamina , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/metabolismo , beta-Arrestina 2 , beta-Arrestinas
10.
Cancer Res ; 54(2): 518-22, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8275490

RESUMO

Previously, we identified an amplified gene in a stomach cancer cell line, KATO-III, and designated it K-sam. This gene was later found to be identical with a gene for a receptor tyrosine kinase, bek/FGFR2. One of the characteristics of the K-sam gene is structural diversity of its transcripts; K-sam complementary DNA (cDNA) cloned from human brain (K-sam-I) has a completely different sequence at the third extracellular immunoglobulin-like domain as compared to that of the K-sam cDNA derived from KATO-III cells (K-sam-II). Recent study has revealed that this difference signifies a differential ligand affinity; the receptor encoded by the K-sam-I cDNA has a high affinity for basic fibroblast growth factor (bFGF), while the K-sam-II cDNA corresponds to a receptor with the high affinity for keratinocyte growth factor (KGF). Reverse transcription-polymerase chain reaction and RNA blot analysis showed that the K-sam-II-type transcript was present in carcinoma cell lines but not in any of the sarcoma cell lines examined. The K-sam-I-type transcript was expressed in both carcinoma and sarcoma cell lines. Furthermore, KGF enhanced the DNA synthesis of the esophageal cancer cells, TE-1, in a dose-dependent manner, while the effect of bFGF was not substantial. In contrast, the glioblastoma cell line, A-172, that expressed the bFGF receptor showed a mitogenic response to bFGF but not to KGF. These data suggest that KGF is a growth factor used preferentially in cancer cells, and this preference is based on the presence of the K-sam-II-type receptor in carcinoma cells but not in sarcoma cells due to alternative splicing.


Assuntos
Carcinoma/genética , DNA de Neoplasias/biossíntese , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fatores de Crescimento de Fibroblastos , Substâncias de Crescimento/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/análise , Sarcoma/genética , Teratoma/genética , Sequência de Bases , Carcinoma/química , Fator 10 de Crescimento de Fibroblastos , Fator 7 de Crescimento de Fibroblastos , Regulação Neoplásica da Expressão Gênica , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sondas RNA , Sarcoma/química , Teratoma/química , Células Tumorais Cultivadas
11.
Cancer Res ; 54(12): 3237-41, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8205545

RESUMO

K-sam, also designated fibroblast growth factor receptor 2/BEK, was originally cloned from a stomach cancer cell line KATO-III. The gene is amplified and overexpressed preferentially in poorly differentiated types of stomach cancers. The major K-sam transcript in KATO-III cells encodes a receptor protein with a truncated carboxyl terminus and with a high-affinity binding site for keratinocyte growth factor. This truncated type is produced by an alternative splicing mechanism, and in normal tissues, the truncated type is far less prevalent than the untruncated form. The variant K-sam complementary DNA lacks tyrosine 769, which is a putative phospholipase C gamma 1 association site, and showed a higher transforming activity to NIH3T3 cells than the untruncated form, which is identical with the keratinocyte growth factor receptor.


Assuntos
Adenocarcinoma/genética , Processamento Alternativo , RNA Mensageiro/genética , Receptores de Fatores de Crescimento de Fibroblastos/genética , Neoplasias Gástricas/genética , Transformação Genética , Células 3T3/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA de Neoplasias/genética , Humanos , Camundongos , Dados de Sequência Molecular , Transcrição Gênica , Células Tumorais Cultivadas
12.
Cancer Res ; 57(16): 3548-53, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9270027

RESUMO

An improved cDNA selection method was established to isolate expressed genes efficiently from an amplified chromosome region in human cancer. Biotinylated yeast artificial chromosome DNA containing c-ERBB-2 was hybridized in solution with PCR-amplifiable cDNAs of an esophageal cancer cell line bearing the c-ERBB-2 amplification. After capturing the hybrids on avidin-coated magnetic beads, the cDNAs were amplified by PCR. Four new genes (A39, C51, CAB1, and GRB-7) coamplified with c-ERBB-2 were isolated from the enriched cDNA library. CAB1, GRB-7, and c-ERBB-2 were overexpressed in gastric and esophageal cancer cells in correspondence with the amplification. The deduced amino acid sequence of the CAB1 gene had significant homology to the recently discovered steroidogenic acute regulatory protein, StAR, which plays an essential role in cholesterol transport to mitochondria. It was established that multiple overexpressed genes are frequently present in a single amplicon.


Assuntos
Proteínas de Transporte/genética , Colesterol/metabolismo , Neoplasias Esofágicas/genética , Genes erbB-2/genética , Proteínas de Membrana , Neoplasias Gástricas/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Transporte/metabolismo , Mapeamento Cromossômico , DNA Complementar/genética , Neoplasias Esofágicas/metabolismo , Proteína Adaptadora GRB7 , Humanos , Dados de Sequência Molecular , Proteínas/genética , Proteínas/metabolismo , Análise de Sequência de DNA , Neoplasias Gástricas/metabolismo , Células Tumorais Cultivadas
13.
Neurology ; 87(19): 2006-2015, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27742816

RESUMO

OBJECTIVE: To investigate the clinical and epidemiologic features of pediatric acquired demyelinating syndromes (ADS) of the CNS in Japan. METHODS: We conducted a nationwide survey and collected clinical data on children with ADS aged 15 years or younger, who visited hospitals between 2005 and 2007. RESULTS: Among 977 hospitals enrolled, 723 (74.0%) responded to our inquiries and reported a total of 439 patients as follows: 244 with acute disseminated encephalomyelitis (ADEM), 117 with multiple sclerosis (MS), 14 with neuromyelitis optica (NMO), and 64 with other ADS. We collected and analyzed detailed data from 204 cases, including those with ADEM (66), MS (58), and NMO (10). We observed the following: (1) the estimated annual incidence rate of pediatric ADEM in Japan was 0.40 per 100,000 children (95% confidence interval [CI], 0.34-0.46), with the lowest prevalence in the north; (2) the estimated prevalence rate of MS was 0.69 per 100,000 children (95% CI, 0.58-0.80), with the lowest prevalence in the south; (3) NMO in Japan was rare, with an estimated prevalence of 0.06 per 100,000 children (95% CI, 0.04-0.08); and (4) the sex ratio and mean age at onset varied by ADS type, and (5) male/female ratios correlated with ages at onset in each ADS group. CONCLUSIONS: Our results clarify the characteristic clinical features of pediatric ADS in the Japanese population.


Assuntos
Doenças Desmielinizantes/epidemiologia , Criança , Pré-Escolar , Doenças Desmielinizantes/classificação , Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/tratamento farmacológico , Feminino , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Estudos Retrospectivos , Esteroides/uso terapêutico , Inquéritos e Questionários
14.
Biochim Biophys Acta ; 1412(1): 66-77, 1999 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-10354495

RESUMO

The plasma membrane NADH oxidase activity partially purified from the surface of HeLa cells exhibited hydroquinone oxidase activity. The preparations completely lacked NADH:ubiquinone reductase activity. However, in the absence of NADH, reduced coenzyme Q10 (Q10H2=ubiquinol) was oxidized at a rate of 15+/-6 nmol min-1 mg protein-1 depending on degree of purification. The apparent Km for Q10H2 oxidation was 33 microM. Activities were inhibited competitively by the cancer cell-specific NADH oxidase inhibitors, capsaicin and the antitumor sulfonylurea N-(4-methylphenylsulfonyl)-N'-(4-chlorophenyl)urea (LY181984). With coenzyme Q0, where the preparations were unable to carry out either NADH:quinone reduction or reduced quinone oxidation, quinol oxidation was observed with an equal mixture of the Q0 and Q0H2 forms. With the mixture, a rate of Q0H2 oxidation of 8-17 nmol min-1 mg protein-1 was observed with an apparent Km of 0.22 mM. The rate of Q10H2 oxidation was not stimulated by addition of equal amounts of Q10 and Q10H2. However, addition of Q0 to the Q10H2 did stimulate. The oxidation of Q10H2 proceeded with what appeared to be a two-electron transfer. The oxidation of Q0H2 may involve Q0, but the mechanism was not clear. The findings suggest the potential participation of the plasma membrane NADH oxidase as a terminal oxidase of plasma membrane electron transport from cytosolic NAD(P)H via naturally occurring hydroquinones to acceptors at the cell surface.


Assuntos
Membrana Celular/enzimologia , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Oxirredutases/metabolismo , Citoproteção , Células HeLa , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Hidroquinonas/metabolismo , Complexos Multienzimáticos/antagonistas & inibidores , NAD/metabolismo , NADH NADPH Oxirredutases/antagonistas & inibidores , Cianeto de Potássio
15.
Forensic Sci Int ; 148(2-3): 131-7, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15639607

RESUMO

The metabolism of methamphetamine (MA) and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in freshly isolated rat hepatocytes was investigated, and compared with in vivo results. A suspended hepatocyte culture, established from male Wistar rats using a collagenase perfusion technique, was incubated in the presence of MA or 2C-B. After enzymatic hydrolysis of the conjugated forms, the metabolites were extracted by liquid-liquid partition and analyzed by gas chromatography/mass spectrometry (GC/MS). Amphetamine, p-hydroxymethamphetamine and p-hydroxyamphetamine were detected in the culture fluids of the rat hepatocytes inoculated with MA. The alcohol derivative, carboxylic acid derivative, 2-O-desmethyl-2C-B, 2-O-desmethyl-N-acetyl-2C-B and 5-O-desmethyl-N-acetyl-2C-B were detected in the case of 2C-B. The major metabolite of MA in rat hepatocytes was p-hydroxymethamphetamine. This is in good agreement with the urinary excretion profile for rats that were fed MA. 2-O-Desmethyl-2C-B and the carboxylic acid derivative were the major recovered metabolites of 2C-B in the rat hepatocyte culture, a slight deviation from the in vivo findings, in which 5-O-desmethyl-N-acetyl-2C-B was found to be the main component. Metabolites with a hydroxy group were largely present in their conjugated forms in the culture fluids, except for 2-O-desmethyl-2C-B. Taking these results into consideration, a primary hepatocyte culture system has the potential to provide a quick and handy method for estimating the in vivo metabolic fate of abused drugs.


Assuntos
Estimulantes do Sistema Nervoso Central/metabolismo , 2,5-Dimetoxi-4-Metilanfetamina/análogos & derivados , 2,5-Dimetoxi-4-Metilanfetamina/metabolismo , Alucinógenos/metabolismo , Hepatócitos/metabolismo , Metanfetamina/análogos & derivados , Metanfetamina/metabolismo , Anfetamina/metabolismo , Animais , Ácidos Carboxílicos/química , Células Cultivadas , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Modelos Animais , Estrutura Molecular , Ratos , Ratos Wistar , Simpatomiméticos/metabolismo , p-Hidroxianfetamina/metabolismo
16.
Mol Aspects Med ; 18 Suppl: S71-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9266508

RESUMO

To confirm whether or not cytosolic NADPH-UQ reductase is involved in the recycling of cellular ubiquinol (UQH2) consumed during lipid peroxidation, the effect of a UQ-10 supplement on the NADPH-UQ reductase and cellular defense against oxidative damage in rat livers was investigated. Supplements of UQ-10 for 14 days enhanced the levels of UQH2-10 and NADPH-UQ reductase in rat livers without any appreciable changes in other antioxidant contents and related enzyme activities. However, the injection of carbon tetrachloride (CCl4) into the rats induced lipid peroxidation and decreased the cellular UQH2-10 contents (and increased equivalent amounts of UQ-10), as well as decreasing the ascorbic acid, reduced glutathione (GSH) and alpha-tocopherol contents of the rat livers. Administration of the UQ-10 supplement prior to the CCl4 treatment spared alpha-tocopherol (but not GSH or ascorbic acid), inhibited lipid peroxidation, and thus improved CCl4-induced hepatitis. These findings support the notion that NADPH-UQ reductase in cytosol is the enzyme responsible for the regeneration of UQH2 from UQ formed by lipid peroxidation in cells.


Assuntos
Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/enzimologia , NAD(P)H Desidrogenase (Quinona)/metabolismo , Ubiquinona/análogos & derivados , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Citosol/enzimologia , Fígado/efeitos dos fármacos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Oxirredução , Ratos , Ratos Wistar , Organismos Livres de Patógenos Específicos , Ubiquinona/metabolismo , Ubiquinona/farmacologia , Ubiquinona/uso terapêutico
17.
FEBS Lett ; 314(3): 331-4, 1992 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-1468565

RESUMO

Ubiquinone (UQ) reductase activity which reduces UQ to ubiquinol (UQH2) in rat tissues was roughly proportional to the UQH2/total UQ ratio in respective tissues. The highest activity was found in the liver, showing the highest UQH2/total UQ ratio. A greater part of liver UQ reductase activity was located in the cytosol. Within a week, the liver UQ reductase activity decreased by 80% even at -20 degrees C. The DT-diaphorase activity was stable. UQ reductase required NADPH as the hydrogen donor and was not inhibited by a less than 1 microM concentration of dicoumarol. There was no stimulation of UQ reductase in the presence of bovine serum albumin nor in Triton X-100. Yet, both stimulated DT-diaphorase. As a result, UQ reductase appeared to be a novel NADPH-UQ oxidoreductase and responsible for the UQ redox state in liver.


Assuntos
Citosol/enzimologia , Fígado/enzimologia , NAD(P)H Desidrogenase (Quinona)/metabolismo , Animais , Masculino , Mitocôndrias/enzimologia , Especificidade de Órgãos , Ratos , Ratos Wistar , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
18.
J Comp Neurol ; 398(3): 309-22, 1998 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-9714145

RESUMO

The axons of the optic nerve layer are known to be myelinated by oligodendrocytes in the chick retina. The development of the retinal oligodendrocytes has been studied immunohistochemically with antibodies against oligodendrocyte lineage: monoclonal antibodies O4 and O1, and an antibody against myelin basic protein. O4 positive (O4+) cells were first detected in the retina on the tenth day of incubation (embryonic day (E)10, stage 36). The labeled cells were located in the optic nerve layer close to the optic fissure. Most were unipolar in shape, extending a leading process with a growth cone toward the periphery of the retina. By E12, unipolar O4+ cells had spread to the middle of the retina. Many O4+ cells close to the optic fissure showed radial arrangement with extension of processes toward the inner limiting membrane. O1+ oligodendrocytes were first observed in the E14 retina positioned just above (interiorly to) retinal ganglion cells. These labeled cells extended fine processes in the optic nerve layer. Limited numbers of myelin basic protein-positive cells were present by E16 and located interiorly to the retinal ganglion cells. In addition to the oligodendrocyte in the optic nerve layer, a limited number of O4+ cells were observed in the inner nuclear layer by E14, and they became O1+ by E18. Furthermore, explant culture experiments showed E10 to be the youngest stage at which the retina contained oligodendrocyte precursors. An intraventricular inj ection of fluorescent dye 1,1',dioctadecyl-3,3,3',3-tetramethylindocarbocyanine perchlorate (DiI) at E6 yielded O4+/DiI+ cells in the retina at E10, which provided direct evidence to support migration of oligodendrocyte precursor into the retina. The present results demonstrated the sequential appearance of the cells of oligodendrocyte lineage and the detailed morphology of the developing oligodendrocytes in the retina. These morphologic features strongly suggested that retinal oligodendrocytes were derived from the optic nerve and spread by migration through the optic nerve layer.


Assuntos
Oligodendroglia/ultraestrutura , Retina/embriologia , Retina/ultraestrutura , Animais , Anticorpos Monoclonais , Carbocianinas , Embrião de Galinha , Corantes Fluorescentes , Imuno-Histoquímica , Injeções Intraventriculares , Nervo Óptico/citologia , Nervo Óptico/embriologia , Nervo Óptico/ultraestrutura
19.
J Comp Neurol ; 419(2): 205-22, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-10722999

RESUMO

The projections from the subiculum to the hypothalamus were comprehensively examined in the rat by using the anterograde Phaseolus vulgaris leucoagglutinin (PHA-L) and retrograde cholera toxin B subunit (CTb) methods. Tracing of efferents with PHA-L indicated that the medial preoptic region received projection fibers from the temporal two-thirds of the subiculum, whereas the anterior, tuberal, and mammillary regions received those from the full longitudinal extent of the subiculum. The subicular projections to the anterior and tuberal hypothalamic regions were also found to be organized in a topographical manner such that the temporal-to-septal axis of origin in the subiculum determined a ventromedial-to-dorsolateral axis of termination in the medial zone of the hypothalamus: Massive labeled fibers from the temporalmost part of the subiculum terminated in the subparaventricular zone and its caudal continuum around the dorsal and medial aspects of the ventromedial nucleus, and those from progressively more septal parts terminated in progressively more dorsolateral parts of the medial zone. In addition, the temporal-to-septal axis of origin in the subiculum tended to determine a medial-to-lateral axis of termination in the preoptic region as well as a ventral-to-dorsal axis of termination in the mammillary region. Furthermore, the temporal-to-septal axis of origin in the septal two-thirds of the subiculum corresponded to a ventrolateral-to-dorsomedial axis of termination in the medial mammillary nucleus. The topographical projections from the subiculum to the medial zone of the hypothalamus were confirmed by CTb experiments, representatively in the subicular projections to the anterior hypothalamic region. These results suggest that different populations of neurons existing along the longitudinal axis of the subiculum may exert their influences on the execution of different hypothalamic functions.


Assuntos
Hipocampo/fisiologia , Hipotálamo/fisiologia , Ratos/fisiologia , Transmissão Sináptica/fisiologia , Animais , Mapeamento Encefálico , Toxina da Cólera , Masculino , Fito-Hemaglutininas , Ratos Wistar
20.
Bone ; 22(5): 515-22, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9600786

RESUMO

This study was undertaken to examine bone responses to human parathyroid hormone (hPTH) at various skeletal sites. Forty 6-month-old female Wistar rats were divided into four groups, and bilateral ovariectomy (ovx) was performed in three of the four groups (n=30). The other group (n=10) received sham surgery (sham). Four weeks after the ovx, hPTH(1-34) administration was started. The ovx rats received 5 microg/kg per day of PTH (PTH-5; n=10), 10 microg/kg per day of PTH (PTH-10; n=10), or vehicle (PTH-v; n=10), three times a week for 24 weeks. Thereafter, PTH was withdrawn for 16 weeks followed by readministration at the same dosage for 8 weeks. The bone mineral content (BMC) at the whole skeleton and the bone mineral density (BMD) at the lumbar vertebrae, caudal vertebrae, distal femur, diaphysis of the femur, proximal tibia, and skull were longitudinally measured by dual-energy x-ray absorptiometry (DXA) at 4-week intervals during the experimental period. Thirteen rats that died during the experimental period were excluded from the analysis. As a result, the whole skeleton showed an increase in BMC during the PTH administration, whereas no withdrawal or readministration effects were observed. The metaphysis showed a highly sensitive bone response, while the lumbar vertebrae and diaphysis showed a moderate magnitude of changes in bone mass during the PTH administration. The skull and the caudal vertebrae did not show sensitive responses to PTH. After withdrawal, the BMD was markedly decreased at the sites that showed marked increases in BMD after PTH administration. The PTH readministration increased the BMD again at the sites that showed sensitive responses after the initial administration. Strength tests were also performed when the readministration was completed. The ultimate loads for the femur and vertebral body in the PTH-treated groups were significantly higher than those in the vehicle-treated group. In conclusion, the response to PTH in ovx rats varied among skeletal sites; withdrawal-related decreases were marked at the sites showing marked increases in bone mass related to PTH administration, and PTH readministration may be sufficiently effective.


Assuntos
Densidade Óssea/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Vértebras Lombares/efeitos dos fármacos , Crânio/efeitos dos fármacos , Teriparatida/farmacologia , Tíbia/efeitos dos fármacos , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Relação Dose-Resposta a Droga , Feminino , Fêmur/fisiologia , Vértebras Lombares/fisiologia , Ovariectomia , Ratos , Ratos Wistar , Crânio/fisiologia , Teriparatida/administração & dosagem , Tíbia/fisiologia
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