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1.
Geophys Res Lett ; 48(11): e2021GL093419, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34433990

RESUMO

The annual 14C data in tree rings is an outstanding proxy for uncovering extreme solar energetic particle (SEP) events in the past. Signatures of extreme SEP events have been reported in 774/775 CE, 992/993 CE, and ∼660 BCE. Here, we report another rapid increase of 14C concentration in tree rings from California, Switzerland, and Finland around 5410 BCE. These 14C data series show a significant increase of ∼6‰ in 5411-5410 BCE. The signature of 14C variation is very similar to the confirmed three SEP events and points to an extreme short-term flux of cosmic ray radiation into the atmosphere. The rapid 14C increase in 5411/5410 BCE rings occurred during a period of high solar activity and 60 years after a grand 14C excursion during 5481-5471 BCE. The similarity of our 14C data to previous events suggests that the origin of the 5410 BCE event is an extreme SEP event.

2.
J Clin Pharm Ther ; 38(1): 19-23, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23030252

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Pilocarpine, a muscarinic receptor agonist, has been used for the treatment of dry mouth. Salivary glands are supplied with nerve fibres that contain neuropeptides, such as substance P, calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP), which are important modulators of salivation. It is known that measurement of salivary and plasma levels of neuropeptides is useful for assessing the dose-pharmacological effect relationship of drugs. The relationship between the action of pilocarpine and neuropeptides in humans has not been studied. Moreover, studies evaluate the usefulness of drug salivary levels in the pharmacological evaluation of drugs are scarce. The aim of this study was to examine the effects of pilocarpine on the levels of substance P-, CGRP- and VIP-like immunoreactive substances (IS) in saliva and plasma taken in healthy humans. METHODS: Five healthy male subjects participated in this study. Pilocarpine tablet (10 mg) or placebo tablet was orally administered with 100 mL of water. Each subject was administered placebo and drug with an interval of 4 weeks in between. Saliva was sampled before and at 20, 40, 60, 90, 120, 180 and 240 min after administration of the test substances. Venous blood samples (10 mL) were also taken from a forearm vein at each time interval. The samples were then enzyme immunoassayed using a highly sensitive system for substance P-, CGRP- and VIP-IS. The amount of saliva was measured by the Saxon test. RESULTS: A single oral administration of pilocarpine increased the release of salivary substance P-IS (the area under the concentration-time curve: AUC(0→240 min)) compared with the placebo. Pilocarpine also significantly increased the release of salivary CGRP-IS (AUC(0→240 min)). Pilocarpine significantly increased the release of plasma CGRP-IS. The salivary volume correlated with the salivary level of substance P and CGRP-IS (r = 0·84, P < 0·05 and r = 0·59, P < 0·05, respectively). AUC(0→240 min) for substance P-IS in saliva correlated with that for plasma (r = 0·78, P < 0·05). WHAT IS NEW AND CONCLUSION: Pilocarpine increases the release of salivary substance P and CGRP-IS. This suggests that one mechanism by which pilocarpine improves dry mouth is by local stimulation of neuropeptidergic nerves. Moreover, saliva levels of substance P showed good correlation with the plasma levels. The substance P levels in saliva and plasma may be good indicators of the effects of drugs used in dry mouth/xerostomic patients.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/efeitos dos fármacos , Agonistas Muscarínicos/farmacologia , Pilocarpina/farmacologia , Substância P/efeitos dos fármacos , Administração Oral , Adulto , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Humanos , Masculino , Saliva/metabolismo , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/metabolismo , Substância P/metabolismo , Fatores de Tempo , Peptídeo Intestinal Vasoativo/metabolismo , Adulto Jovem
7.
J Thromb Haemost ; 4(2): 377-84, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16420569

RESUMO

BACKGROUND: Precise assessment of clotting function is essential for monitoring of hemostatic treatment for hemophilias A and B. MATERIALS AND METHODS: Clot waveform analysis and thrombin generation assays were performed on factor (F) VIII- and FIX-deficient plasmas, which had been reconstituted with known amounts of recombinant FVIII (rFVIII) and affinity-purified FIX respectively. Clot waveforms were assessed qualitatively and quantitatively by measuring the parameters clotting time, maximum coagulation velocity (Min1), and maximum coagulation acceleration (Min2). The thrombin generation assay was also assessed qualitatively and measurements made of time to peak and peak height. RESULTS: Overall results obtained with both assays showed good correlation for both clotting factors confirming that the changes in clotting waveform reflected changes in thrombin generation. Both assays demonstrated a predictable dose response to the addition of FVIII or IX. However, clot waveform analysis was more sensitive than the thrombin generation assay, particularly in detecting very low levels (0-0.1 IU dL(-1)) of both factors. CONCLUSIONS: These data suggest that the application of clot waveform analysis to the routine management of the hemophiliacs could increase our understanding of the clinical significance of low levels of FVIII and FIX that cannot be measured by assays in current use. This may be particularly useful in the management of hemophiliacs with inhibitors or undergoing gene therapy.


Assuntos
Testes de Coagulação Sanguínea/métodos , Fator IX/análise , Fator VIII/análise , Hemofilia A/sangue , Hemofilia B/sangue , Biometria , Testes de Coagulação Sanguínea/estatística & dados numéricos , Fator IX/administração & dosagem , Fator VIII/administração & dosagem , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Humanos , Técnicas In Vitro , Masculino , Tempo de Tromboplastina Parcial/métodos , Tempo de Tromboplastina Parcial/estatística & dados numéricos , Proteínas Recombinantes/administração & dosagem , Sensibilidade e Especificidade , Tempo de Trombina/métodos , Tempo de Trombina/estatística & dados numéricos
8.
J Thromb Haemost ; 14(4): 667-74, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27061057

RESUMO

BACKGROUND: The clinical phenotype of von Willebrand disease (VWD) is heterogeneous, and von Willebrand factor ristocetin cofactor activity (VWF:RCo) does not always reflect clinical severity, especially in VWD type 1. We have reported the potential of a microchip flow-chamber system (Total-Thrombus Formation Analysis System [T-TAS®]) for assessing physiologic hemostasis in VWD. Aim To evaluate the relationship between T-TAS, bleeding score (BS) and laboratory test results in type 1 VWD patients. METHODS: Microchips coated with collagen (platelet chip [PL-chip]) or collagen/thromboplastin (AR-chip) were used to assess platelet thrombus formation (PTF) at high shear rates or fibrin-rich PTF at low shear rates, respectively, in whole blood from 50 patients. The times needed for the flow pressure to increase by 10 kPa and 30 kPa (T10 and T30 ) from baseline were calculated from flow pressure curves. BS was determined by the use of a standardized questionnaire. RESULTS: PL-T10 values correlated with BS (R(2) ~ 0.45) better than VWF:RCo (R(2) ~ 0.36), irrespective of the flow rate, whereas AR-T10 showed only a weak correlation with BS (R(2) ~ 0.18). Patients with PL-T10 > 10 min or AR-T10 > 30 min had lower VWF levels and higher BS than those with PL-T10 ≤ 10 min or AR-T10 ≤ 30 min, and the greatest differences were observed with PL-T10. Clinical severity appeared to correlate best with PL-T10 > 8 min. BS was significantly higher in patients with VWF:RCo of < 10 IU dL(-1) than in those with VWF:RCo of 10 IU dL(-1) to < 25 IU dL(-1) and 25-40 IU dL(-1). In patients with VWF:RCo of < 10 IU dL(-1) , BS was significantly higher in those with PL-T10 > 8 min than in those with PL-T10 ≤ 8 min. CONCLUSION: T-TAS could be a useful technique for discriminating and predicting BS in VWD type 1 patients.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Doença de von Willebrand Tipo 1/sangue , Fator de von Willebrand/química , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Colágeno/química , Feminino , Hemorragia , Hemostasia , Humanos , Lactente , Masculino , Microfluídica , Pessoa de Meia-Idade , Fenótipo , Pressão , Índice de Gravidade de Doença , Resistência ao Cisalhamento , Estresse Mecânico , Inquéritos e Questionários , Tromboplastina/química , Trombose , Adulto Jovem
9.
Int J Impot Res ; 17(3): 259-63, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15616608

RESUMO

The International Society for the Study of the Aging Male (ISSAM) recommends that a diagnosis be based on a patient's total testosterone (TT), calculated free testosterone (cFT), or calculated bioavailable testosterone (cBT) for partial androgen deficiency of the aging male (PADAM). The purpose of this study was to confirm whether hypogonadism of patients with PADAM is related to symptoms and clarify which criteria of testosterone recommended by ISSAM is suitable for Japanese patients. A total of 90 patients with PADAM symptoms were included in this study. Endocrinologic profiles were reviewed as appropriate, and PADAM symptoms were judged by means of several questionnaires. Laboratory values and symptoms were compared between patients with and without hypogonadism. Even when any criterion of testosterone was used for diagnosis of hypogonadism, AMS (total and subscales), IIEF-5, or SDS scores of PADAM symptoms did not differ significantly between patients classified as having and not having hypogonadism. No other endocrinologic variables than testosterone differed significantly between them, either. PADAM symptoms are not related to testosterone level and it is still obscure whether ISSAM's criterion can be adopted for Japanese patients with PADAM. Other pathology needs to be addressed for evaluation and diagnosis of PADAM in Japan.


Assuntos
Envelhecimento , Androgênios/deficiência , Andropausa/fisiologia , Testosterona/sangue , Humanos , Hipogonadismo/sangue , Hipogonadismo/diagnóstico , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Valores de Referência , Inquéritos e Questionários
10.
J Thromb Haemost ; 13(10): 1843-53, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26278069

RESUMO

BACKGROUND: In mild hemophilia A (MHA) patients, the risk of inhibitor development is generally low, but some factor VIII (FVIII) gene missense mutations are associated with a higher inhibitor incidence. OBJECTIVE: To investigate the mechanism(s) of inhibitor development in MHA. METHODS AND RESULTS: A patient, HA78, with MHA with a novel P1809L missense mutation in the A3 domain, exhibited significant residual FVIII activity ( FVIII: C ~10 IU dL(-1) ), despite the development of an inhibitor (5.6 BU mL(-1) ). Purified HA78-IgG significantly depressed FVIII: C from normal plasma but not from patient's plasma without inhibitor, indicating that this IgG inhibited allogeneic but not autologous FVIII. The HA78-IgG blocked thrombin and FXa-catalyzed FVIII cleavage but had little effect on FVIII binding to von Willebrand factor and phospholipid. The IgG recognized a C2 epitope close or overlapping the previously described anti-C2 ESH8 epitope. Similarly, a recombinant FVIII-P1809L mutant was little inactivated by HA78-IgG. This mutant demonstrated ~3-fold lower binding affinities to von Willebrand factor and phospholipid compared with wild-type, while reactions with thrombin or FXa were not impaired. Reaction of FVIII-P1809L with the alternative anti-C2 ESH4 showed only an ~20% inhibition compared with wild-type FVIII but was similar to wild-type after incubation with ESH8. A surface plasmon resonance-based assay demonstrated that anti-C2 ESH4 bound to FVIII-P1809L with ~10(2) -fold lower affinity compared with ESH8. CONCLUSION: These results indicated that the P1809L mutation in A3 induced the conformational change in the FVIII molecule that hampered antigenic determinant(s) located in the C2 domain and might result in the inhibitor development.


Assuntos
Autoanticorpos/sangue , Coagulação Sanguínea/genética , Complemento C2/imunologia , Fator VIII/genética , Hemofilia A/genética , Mutação de Sentido Incorreto , Especificidade de Anticorpos , Testes de Coagulação Sanguínea , Reações Cruzadas , Análise Mutacional de DNA , Mapeamento de Epitopos , Epitopos , Fator VIII/química , Fator VIII/imunologia , Fator VIII/metabolismo , Predisposição Genética para Doença , Hemofilia A/sangue , Hemofilia A/diagnóstico , Humanos , Fenótipo , Estrutura Terciária de Proteína , Índice de Gravidade de Doença , Relação Estrutura-Atividade
11.
Endocrinology ; 118(6): 2268-75, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3486119

RESUMO

Two pituitaries from 7-week-old female rats were grafted under the capsule of the left kidney of 50-day-old male rat to induce hyperprolactinemia. All of the pituitary-grafted and sham-operated rats were hypophysectomized at 56 days of age. The hypophysectomized rats in groups of 4 were given daily sc injections of saline or 9 micrograms NIADDK-ovine-(o)LH-23 for 4 and 5 days starting from days 58 and 70, respectively (short and long term hypophysectomized groups). The metabolism of [3H]progesterone or [14C]androstenedione by testicular homogenates, concentrations of testosterone and 5 alpha-androgens (androsterone plus 5 alpha-androstane-3 alpha, 17 beta-diol) in the serum and testes, and testicular LH receptors were estimated. Hypophysectomy caused significant decreases in testicular enzyme activities per gram of tissue, androgen production, and testicular LH receptors. In the testes of hypophysectomized rats, LH treatment significantly stimulated 5 alpha-reductase and 17-hydroxylase activities. Although pituitary grafts alone showed little or no effect on these testicular enzyme activities, hyperprolactinemia induced by the grafts markedly enhanced the LH-stimulated 5 alpha-reductase activity in both groups, especially in the long term hypophysectomized group. Therefore, androsterone and 5 alpha-androstane-3 alpha,17 beta-diol were shown to be the major C19-steroid products (immature type of testicular androgen production) in the LH- and PRL-stimulated testes of long term hypophysectomized adult rats. On the other hand, hyperprolactinemia was associated with a significant inhibition and a slight increase of the LH-stimulated 17-hydroxylase activities in the short and long term hypophysectomized groups, respectively. This difference can be attributed to both a PRL-induced increase in testicular LH receptors and a PRL-induced inhibition of 17-hydroxylase via a postreceptor mechanism(s). The present findings demonstrate for the first time that PRL directly stimulates LH-induced 5 alpha-reductase activity in the testes. It appears that PRL may play a role in the increased production of 5 alpha-C19-steroids and the parallel decrease of testosterone production in immature rat testes.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Hipofisectomia , Hormônio Luteinizante/farmacologia , Prolactina/farmacologia , Testículo/enzimologia , 17-Hidroxiesteroide Desidrogenases/metabolismo , Androstano-3,17-diol/biossíntese , Androsterona/biossíntese , Animais , Gonadotropina Coriônica/metabolismo , Feminino , Masculino , Tamanho do Órgão , Hipófise/transplante , Prolactina/sangue , Próstata/anatomia & histologia , Ratos , Ratos Endogâmicos , Esteroide 17-alfa-Hidroxilase/metabolismo , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testosterona/biossíntese
12.
FEBS Lett ; 218(2): 222-6, 1987 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-2885226

RESUMO

A mutant strain KF87 of E. coli with a defective beta-subunit (Ala-151----Val) of F1-ATPase was isolated. The mutation is within the conserved sequence (G-X-X-X-X-G-K-T/S) of nucleotide-binding proteins. The mutant F1-ATPase had a much higher rate of uni-site hydrolysis of ATP than the wild type, and about 6% of the wild-type multi-site activity. The mutant enzyme showed defective transmission of conformational change(s) between the ligand- and aurovertin-binding sites.


Assuntos
Proteínas de Transporte/genética , Proteína Receptora de AMP Cíclico , Escherichia coli/enzimologia , ATPases Translocadoras de Prótons/genética , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Aurovertinas/metabolismo , Sequência de Bases , DNA Recombinante , Escherichia coli/genética , Hidrólise , Mutação , Oncogenes , Fosfatos/metabolismo
13.
J Immunol Methods ; 130(2): 217-22, 1990 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-2197332

RESUMO

A sensitive and specific microenzyme immunoassay (EIA) procedure for porcine brain natriuretic peptide (BNP)-like immunoreactivity has been developed. Enzyme-labeled antigen was prepared by conjugation of synthetic BNP with beta-D-galactosidase using N-(epsilon-maleimidocaproyloxy)succinimide method. Using a second antibody-coated immunoplate, the minimum amount of BNP-like immunoreactivity (BNP-LI) detectable by this assay system was 1.6 fmol/well. When porcine BNP-LI in porcine plasma was assayed by the present method levels between 1 and 8 pmol/l were detected. Gel filtration of porcine plasma extracts on Sephadex G-25 revealed the presence of two immunoreactive peaks; one eluted at a position identical with that of BNP-26 and the other eluted earlier, close the position of BNP-32.


Assuntos
Proteínas do Tecido Nervoso/sangue , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Cromatografia em Gel , Humanos , Técnicas Imunoenzimáticas , Dados de Sequência Molecular , Peptídeo Natriurético Encefálico , Ratos , Homologia de Sequência do Ácido Nucleico , Suínos
14.
J Dermatol Sci ; 17(2): 93-100, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9673890

RESUMO

In order to know the possible effects of gastrin releasing peptide (GRP) on nevus cells and melanocytes, we studied the effect of GRP on the proliferation of cultured human nevus cells and normal melanocytes. MTS assay showed that GRP stimulated the growth of viable melanocytes at 1000 ng/ml. GRP also stimulated the growth of nevus cells in a dose dependent manner and maximum stimulation was obtained at 100 ng/ml of GRP. GRP was less effective for growth stimulation of normal melanocytes than nevus cells. The cytoplasm of nevus cells were positively stained by polyclonal anti-GRP antibody. We also detected the expression of GRP and GRP receptor mRNAs in these cells by RT-PCR. These results suggest that GRP acts as an autocrine growth factor for nevus cells and normal melanocytes.


Assuntos
Peptídeo Liberador de Gastrina/farmacologia , Melanócitos/efeitos dos fármacos , Nevo/patologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Peptídeo Liberador de Gastrina/biossíntese , Humanos , Imuno-Histoquímica , Melanócitos/citologia , Melanócitos/metabolismo , Nevo/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Receptores da Bombesina/biossíntese , Estimulação Química
15.
J Biochem ; 122(4): 779-87, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9399582

RESUMO

Alanyl aminopeptidase (AAP) was purified to homogeneity from human seminal plasma. The calculated molecular weight of the purified enzyme was approximately 137,000+/-5,000 from light scattering, 140,000 (main) and 137,000 (minor) from non-denatured PAGE and 153,000 from SDS-PAGE in the absence or presence of 2-mercaptoethanol (2-ME). These findings suggest that the enzyme is monomeric in form in human seminal plasma. The enzyme hydrolyzed several amino acid 4-methyl-coumaryl-7-amide (MCA) substrates. The order of Kcat/Km values of AAP at optimal pH (pH 7.5) was Ala- > Lys-Ala- > or = Met- > Leu- > Phe- > Arg- > or = Arg-Arg- > Lys- > Gly-MCAs. AAP was potently inhibited by bestatin, leuhistin, actinonin, amastatin, and 1,10-phenanthroline. These findings suggest that AAP is an aminopeptidase. We determined that the amino acid sequence of the first 22 residues of the enzyme was Ser1-Thr-Thr-Pro-Ser5-Ala-Ser-Ala-Thr-Thr10-Asn-Pro-Al a-Ser-Ala15-Thr-Thr-Leu-Asp-Gln20-Ser-Lys-. This sequence was completely coincident with that downstream of the transmembrane site of human intestinal alanyl aminopeptidase N (CD13). We also isolated cDNA encoding AAP from human prostate cDNA library, sequenced its structure, and confirmed human seminal plasma AAP to be identical with alanyl aminopeptidase N. We postulated that native human seminal plasma alanyl aminopeptidase is released into the seminal plasma after the specific site is cleaved by elastase or an elastase-like enzyme. The enzyme level in human seminal plasma determined by single radial immunodiffusion was 5.2+/-3.2 mg/100 ml (mean+/-SD, n=20) in individuals 20-47 years of age. AAP was immunohistochemically stained in the luminal site-cell membrane of epithelial cells in the prostatic gland and ductuli efferentes of the testis.


Assuntos
Antígenos CD13/isolamento & purificação , Genitália Masculina/enzimologia , Sêmen/enzimologia , Adulto , Sequência de Aminoácidos , Antígenos CD13/antagonistas & inibidores , Antígenos CD13/química , Antígenos CD13/metabolismo , Clonagem Molecular , DNA Complementar , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Humanos , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Indicadores e Reagentes , Ponto Isoelétrico , Cinética , Masculino , Metais , Dados de Sequência Molecular , Peso Molecular , Especificidade por Substrato
16.
J Clin Pharmacol ; 33(9): 851-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8227483

RESUMO

The in vivo serum protein binding parameters of carbamazepine (CBZ) and carbamazepine-10, 11-epoxide (CBZ-E), which was the main metabolite of CBZ in plasma, were determined in sera from 27 patients on CBZ monotherapy. Based on the results by recent studies, the authors assumed that CBZ and CBZ-E binding to serum proteins were composed of specific binding sites on alpha 1-acid glycoprotein (AAG) and albumin. Therefore, the authors determined the binding parameters of each compound by specific binding equation for two proteins. Association constants for drug-AAG binding were .071 L/mumol for CBZ and .016 L/mumol for CBZ-E. Conversely, those for drug-albumin binding were .00052 L/mumol for CBZ and .00072 L/mumol for CBZ-E. Within the investigated total concentration ranges in each compound, the AAG binding contributes largely to the drug-serum protein interactions. Furthermore, our results indicate that the albumin binding contributes to the nonsaturable serum protein binding of these compounds in the therapeutic range.


Assuntos
Proteínas Sanguíneas/metabolismo , Carbamazepina/análogos & derivados , Carbamazepina/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carbamazepina/farmacocinética , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica
17.
J Clin Pharmacol ; 33(2): 130-5, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8440760

RESUMO

Nine healthy subjects received 400 mg sodium valproate orally in the fasting state. Binding parameters of valproic acid to serum proteins were determined by Scatchard analysis for individual series of valproic acid data. Total and unbound (intrinsic) clearances (CLt and CLu) were calculated by dividing the dose by the appropriate area under the serum drug concentration-time curve. Unbound clearance correlated positively with the product of association constant (Ka) and concentration of free protein ((P)) (P < .05). Conversely, no significant correlation was found between CLt and binding parameters. The average unbound concentration correlated negatively with both CLu and ka(P) values. The result indicates an effect of CLu on Ka(P) value of valproic acid.


Assuntos
Proteínas Sanguíneas/metabolismo , Ácido Valproico/farmacocinética , Administração Oral , Adulto , Jejum/metabolismo , Feminino , Humanos , Masculino , Ligação Proteica , Ácido Valproico/administração & dosagem , Ácido Valproico/metabolismo
18.
J Clin Pharmacol ; 35(10): 995-1002, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8568018

RESUMO

In a previous study, an equation with in vivo population binding parameters of carbamazepine and carbamazepine-10, 11-epoxide (CBZ-E) to serum proteins for the relation between unbound and bound serum concentrations was defined. A review by Pynnönen indicates that the average bound/unbound plasma fraction ratio is 3.0 for carbamazepine and 1.0 for CBZ-E. In this study, the ability of equations with in vivo population binding parameters of the previous study (method 1) or with the average bound/unbound plasma fraction ratio of 3.0 of Pynnönen (method 2) to predict the bound serum carbamazepine concentration was retrospectively evaluated using 85 serum samples from 46 patients with epilepsy taking carbamazepine polytherapy. In 21 serum samples from 16 patients, the ability of these equations to predict bound serum CBZ-E concentration was also determined with in vivo population binding parameters from the previous study (method A) or with the average bound/unbound plasma fraction ratio of 1.0 of Pynnönen (method B). Mean prediction error, mean absolute prediction error (MAE), and root mean squared error (RMSE) were calculated for each method, and these values served as a measure of prediction bias and precision. Method 1 showed a bias to overpredict bound serum carbamazepine. The MAE and RMSE were significantly smaller with method 2 (MAE = 2.4 mumol/L; RMSE = 3.2 mumol/L) than with method 1 (MAE = 4.1 mumol/L; RMSE = 4.8 mumol/L). Method 2 was superior to method 1 in terms of accuracy and precision. For bound CBZ-E prediction, method B had a bias to underprediction. The MAE and RMSE were smaller with method A (MAE = 0.581 mumol/L; RMSE = 0.796 mumol/L) than with method B (MAE = 0.724 mumol/L; RMSE = 0.905 mumol/L). Method A was superior to method B in terms of accuracy and precision.


Assuntos
Anticonvulsivantes/sangue , Carbamazepina/análogos & derivados , Carbamazepina/sangue , Epilepsia/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/uso terapêutico , Proteínas Sanguíneas/metabolismo , Carbamazepina/uso terapêutico , Criança , Pré-Escolar , Epilepsia/tratamento farmacológico , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Reprodutibilidade dos Testes , Estudos Retrospectivos
19.
J Dent Res ; 60(9): 1697-706, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7021620

RESUMO

1) A new adhesive opaque resin containing a reactive monomer, 4-methacryloxy-ethyl trimellitate anhydride (4-META), was prepared, and its application to thermosetting acrylic resin veneer crowns was studied. 2) The 4-META opaque resin was applied to a variety of nickel-chromium dental alloy specimens which had undergone different treatment, and endurance tests were conducted to evaluate the durability of adhesion. 3) Stable adhesion against water penetration was achieved with metal surfaces first etched with HCl and then oxidized with HNO3. A bond strength of 250 kg/cm2 was maintained even after immersion in water at 37 degrees C for 30 wk or at 80 degrees C for ten wk. Furthermore, this value did not decrease even after the specimens were subjected to 500 thermal cycles. 4) The 4-META opaque resin studied can eliminate the necessity for retention devices on metal castings. 5) The smooth 4-META opaque resin should have no adverse effects on gingivae.


Assuntos
Acrilatos , Resinas Epóxi , Metacrilatos , Resinas Acrílicas , Adesividade , Cromo , Ligas Dentárias , Colagem Dentária , Níquel , Propriedades de Superfície
20.
J Gastroenterol ; 31(6): 768-76, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9027638

RESUMO

In rats, changes in gastric nerve fibers containing gastrin-releasing peptide (GRP) in cysteamine-induced duodenal ulcer were investigated in relation to the dynamics of gastrin-producing cells (G-cells). Marked increases in gastric acid secretion and serum gastrin level were observed from 2 h after the administration of cysteamine. The number of G-cells was significantly decreased from 2 h after the injection of cysteamine. Two and 4 h after the administration of cysteamine, the G-cells showed ultrastructural changes characterized by a markedly decreased number of secretory granules. Circulating GRP levels were significantly elevated from 2 h after the administration of cysteamine. In the control group given vehicle only, nerve fibers showing immunoreaction for GRP formed a fine network in the gastric wall and were densely distributed in the oxyntic mucosa, located close to capillaries and demonstrated varicosities that contained either small clear vesicles or GRP-immunopositive vesicles with large cores. Eight h after the administration of cysteamine, there was depleted GRP immunoreactivity, evidenced by a markedly decreased number of vesicles, with large electron-dense cores, in the oxyntic mucosa. These findings suggest that, in cysteamine-induced duodenal ulcer, alterations in gastric nerve fibers containing GRP may be related to hypergastrinemia.


Assuntos
Cisteamina/farmacologia , Fibras Nervosas/efeitos dos fármacos , Peptídeos/metabolismo , Protetores contra Radiação/farmacologia , Estômago/inervação , Animais , Contagem de Células , Cisteamina/toxicidade , Úlcera Duodenal/induzido quimicamente , Úlcera Duodenal/metabolismo , Úlcera Duodenal/patologia , Seguimentos , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Peptídeo Liberador de Gastrina , Gastrinas/biossíntese , Gastrinas/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Microscopia Imunoeletrônica , Fibras Nervosas/metabolismo , Fibras Nervosas/ultraestrutura , Peptídeos/efeitos dos fármacos , Protetores contra Radiação/toxicidade , Radioimunoensaio , Ratos , Ratos Wistar , Estômago/efeitos dos fármacos
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