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1.
J Clin Pharm Ther ; 42(5): 591-597, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28503837

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Anticoagulation therapy with warfarin requires periodic monitoring of prothrombin time-international normalized ratio (PT-INR) and adequate dose adjustments based on the data to minimize the risk of bleeding and thromboembolic events. In our hospital, we have developed protocol-based pharmaceutical care, which we called protocol-based pharmacotherapy management (PBPM), for warfarin therapy. The protocol requires pharmacists to manage timing of blood sampling for measuring PT-INR and warfarin dosage determination based on an algorithm. This study evaluated the efficacy of PBPM in warfarin therapy by comparing to conventional pharmaceutical care. METHODS: From October 2013 to June 2015, a total of 134 hospitalized patients who underwent cardiovascular surgeries received post-operative warfarin therapy. The early series of patients received warfarin therapy as the conventional care (control group, n=77), whereas the latter received warfarin therapy based on the PBPM (PBPM group, n=68). These patients formed the cohort of the present study and were retrospectively analysed. RESULTS: The indications for warfarin included aortic valve replacement (n=56), mitral valve replacement (n=4), mitral valve plasty (n=22) and atrial fibrillation (n=29). There were no differences in patients' characteristics between both groups. The percentage time in therapeutic range in the first 10 days was significantly higher in the PBPM group (47.1%) than that in the control group (34.4%, P<.005). The average time to reach the steady state was significantly (P<.005) shorter in the PBPM group compared to the control group (7.3 vs 8.6 days). WHAT IS NEW AND CONCLUSION: Warfarin therapy based on our novel PBPM was clinically safe and resulted in significantly better anticoagulation control compared to conventional care.


Assuntos
Anticoagulantes/administração & dosagem , Procedimentos Cirúrgicos Cardíacos/métodos , Serviço de Farmácia Hospitalar/organização & administração , Varfarina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anticoagulantes/efeitos adversos , Estudos de Coortes , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos/métodos , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Conduta do Tratamento Medicamentoso/organização & administração , Pessoa de Meia-Idade , Farmacêuticos/organização & administração , Tempo de Protrombina , Estudos Retrospectivos , Tromboembolia/prevenção & controle , Fatores de Tempo , Varfarina/efeitos adversos
2.
Dis Esophagus ; 25(3): 228-34, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21895851

RESUMO

Patients who have received subtotal esophagectomy for thoracic esophageal cancer must be closely monitored for second primary malignancies. The purpose of this study is to review and assess patients who developed a second primary esophageal cancer in the residual cervical esophagus. Between 1996 and 2010, 10 patients were diagnosed in our hospital with esophageal squamous cell cancer in the residual cervical esophagus after undergoing thoracic esophagectomy and were treated with endoscopic or surgical resection. Data from these patients were reviewed retrospectively. Seven of the 10 patients (70%) had multiple primary carcinoma lesions at the time of their esophagectomy. A second primary cancer in the residual cervical esophagus was detected in eight patients during follow-up endoscopic examinations while the patients were still asymptomatic. Seven of the patients underwent endoscopic resection for a superficial cancer. None of those patients experienced any complications, and all are currently alive and cancer-free. The remaining three patients underwent resection of the cervical esophagus with regional lymph node dissection. Two of those patients experienced severe complications; one subsequently died (hospital death) from pneumonia, 12 months after surgery, while the other died from recurrence of his cancer. The third patient is alive and cancer-free. Early detection of a second primary malignancy in the residual cervical esophagus followed by endoscopic resection is the best treatment strategy for patients who previously received subtotal esophagectomy for thoracic esophageal cancer. Surgical resection puts patients at high risk of mortality or morbidity.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia Adjuvante , Esofagectomia/efeitos adversos , Esofagoscopia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/terapia , Radioterapia Adjuvante , Estudos Retrospectivos , Resultado do Tratamento
3.
Dis Esophagus ; 24(3): 166-71, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20946135

RESUMO

We investigated the effectiveness of chemoradiotherapy for the treatment of lymph node recurrence and hematogenous metastasis after esophagectomy for esophageal squamous cell carcinoma. Between 2001 and 2006, 216 patients with thoracic esophageal squamous cell carcinoma had curative esophagectomy. Of those, 23 with lymph node recurrence received chemoradiotherapy (50.0-68.8 Gy). In addition, five patients had isolated recurrences in a distant organ and received chemoradiotherapy (50.0-60.0 Gy). We analyzed outcomes from the radiotherapy for recurrent esophageal cancer. The 1-, 2-, and 5-year survival rates after recurrence for the 23 patients whose lymph node recurrence was treated with chemoradiotherapy were 52, 31, and 24%, respectively, and the median survival time was 13 months. Among the five patients with recurrent tumors in a distant organ, chemoradiotherapy produced a complete response in two patients, a partial response in one patient, and stable disease in two patients, giving an effectiveness rate of 60% (complete response + partial response). Chemoradiotherapy has a beneficial prognostic effect in patients with lymph node recurrence of esophageal squamous cell carcinoma. Chemoradiotherapy for a metastatic tumor in a distant organ may be the treatment of choice in cases where systemic chemotherapy has proven ineffective.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Terapia Combinada , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Esofagectomia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva , Taxa de Sobrevida
4.
Eur Surg Res ; 45(1): 41-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20733316

RESUMO

We report 2 cases of small cell carcinoma of the esophagus treated with esophagectomy as a primary treatment and following chemotherapy. One patient (pT1N1M0) achieved long-term survival, while the other patient (pT1N1M1-lym) died 18 months after surgery. We used reports on 47 Japanese patients receiving esophagectomy as a primary treatment to determine when esophagectomy for small cell carcinoma of the esophagus is indicated. We conclude that esophagectomy as a local treatment provides relatively good long-term survival only in patients without lymph node involvement.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/patologia , Terapia Combinada , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Sobreviventes , Resultado do Tratamento
7.
J Int Med Res ; 32(2): 176-84, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15080022

RESUMO

In this cross-sectional study, we surveyed a population of 101 hypertensive patients in Japan to determine the efficacy of the blood pressure lowering effect of alpha 1-blockers in relation to their body mass index (BMI). We found that doxazosin was frequently administered to obese hypertensive patients; many patients treated with doxazosin were taking concomitant medication. We also demonstrated that the higher the dose of doxazosin, the lower the ambulatory blood pressure measured in the out-patient clinic. Doxazosin showed a more favourable blood pressure lowering effect in patients with a higher BMI. These results suggest that anti-hypertensive drugs are useful when used in obese patients receiving multiple concomitant medications. These patients would normally be considered to show a poor response to anti-hypertensive treatment. Furthermore, we expect the alpha 1-blocker doxazosin to demonstrate a dose-dependent effect in obese patients with hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Índice de Massa Corporal , Doxazossina/uso terapêutico , Hipertensão/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Hipertensão/complicações , Japão , Masculino , Inquéritos e Questionários
8.
Endoscopy ; 35(2): 185-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12561014

RESUMO

It is difficult to accurately diagnose the nature of polypoid lesions in the gallbladder. To increase diagnostic accuracy, we have developed an endoscopic technique for obtaining gallbladder bile, termed endoscopic transpapillary catheterization into the gallbladder (ETCG). We describe here a case of gallbladder carcinoma diagnosed preoperatively by the detection of human telomerase reverse transcriptase (hTERT) mRNA, a catalytic subunit of telomerase, in gallbladder bile obtained using the ETCG technique. A patient with a polypoid lesion 15 mm in diameter in the gallbladder was admitted to our hospital for further examinations. Gallbladder bile collected by the ETCG technique was evaluated cytologically and also analyzed for telomerase activity and hTERT mRNA. Although the results for cytology and telomerase activity were negative, that for hTERT mRNA was positive. Open surgery was carried out and it was confirmed that the lesion was an adenocarcinoma invading the subserosa. The molecular biological analysis of gallbladder bile collected using the ETCG technique was shown to be effective for diagnosing the nature of the polypoid lesion in the gallbladder.


Assuntos
Adenocarcinoma/diagnóstico , Bile/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Vesícula Biliar/diagnóstico , Telomerase/metabolismo , Adenocarcinoma/cirurgia , Idoso , Cateterismo/métodos , Colecistectomia , Proteínas de Ligação a DNA , Endoscopia do Sistema Digestório , Feminino , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Cuidados Pré-Operatórios , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Biochemistry ; 40(37): 11168-75, 2001 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-11551215

RESUMO

Asparagine synthetase catalyzes the ATP-dependent formation of L-asparagine from L-aspartate and L-glutamine, via a beta-aspartyl-AMP intermediate. Since interfering with this enzyme activity might be useful for treating leukemia and solid tumors, we have sought small-molecule inhibitors of Escherichia coli asparagine synthetase B (AS-B) as a model system for the human enzyme. Prior work showed that L-cysteine sulfinic acid competitively inhibits this enzyme by interfering with L-aspartate binding. Here, we demonstrate that cysteine sulfinic acid is also a partial substrate for E. coli asparagine synthetase, acting as a nucleophile to form the sulfur analogue of beta-aspartyl-AMP, which is subsequently hydrolyzed back to cysteine sulfinic acid and AMP in a futile cycle. While cysteine sulfinic acid did not itself constitute a clinically useful inhibitor of asparagine synthetase B, these results suggested that replacing this linkage by a more stable analogue might lead to a more potent inhibitor. A sulfoximine reported recently by Koizumi et al. as a competitive inhibitor of the ammonia-dependent E. coli asparagine synthetase A (AS-A) [Koizumi, M., Hiratake, J., Nakatsu, T., Kato, H., and Oda, J. (1999) J. Am. Chem. Soc. 121, 5799-5800] can be regarded as such a species. We found that this sulfoximine also inhibited AS-B, effectively irreversibly. Unlike either the cysteine sulfinic acid interaction with AS-B or the sulfoximine interaction with AS-A, only AS-B productively engaged in asparagine synthesis could be inactivated by the sulfoximine; free enzyme was unaffected even after extended incubation with the sulfoximine. Taken together, these results support the notion that sulfur-containing analogues of aspartate can serve as platforms for developing useful inhibitors of AS-B.


Assuntos
Monofosfato de Adenosina/farmacologia , Asparagina/biossíntese , Carbono-Nitrogênio Ligases com Glutamina como Doadora de N-Amida/antagonistas & inibidores , Escherichia coli/enzimologia , Metionina Sulfoximina/farmacologia , Monofosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Cisteína/análogos & derivados , Cisteína/farmacologia , Inibidores Enzimáticos/farmacologia , Hidrólise , Metionina Sulfoximina/análogos & derivados , Modelos Químicos , Neurotransmissores , Ressonância Magnética Nuclear Biomolecular , Isótopos de Fósforo , Espectrometria de Massas por Ionização por Electrospray
11.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 8): 1171-3, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11468409

RESUMO

Crystals of endopolygalacturonase I from Stereum purpureum have been obtained by the vapour-diffusion method. Prior to crystallization work, endopolygalacturonase I was deglycosylated with endo-beta-N-acetylglucosaminidase H. The crystal diffracts to ultrahigh (0.96 A) resolution using synchrotron radiation and belongs to space group P1, with unit-cell parameters a = 37.26, b = 46.34, c = 52.05 A, alpha = 67.17, beta = 72.44, gamma = 68.90 degrees.


Assuntos
Basidiomycota/enzimologia , Poligalacturonase/química , Cristalização , Cristalografia por Raios X , Conformação Proteica
13.
Jpn J Physiol ; 50(4): 405-12, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11082538

RESUMO

We attempted to fit heart rate (HR) changes induced by constant exercise loads of different intensities to an exponential hyperbolic sine curve by the least-squares method, and we compared the results with the fitting of the changes to exponential curves. Seven healthy male volunteers performed three different intensities of constant-load exercise on a bicycle ergometer. The exponential hyperbolic sine function adequately fitted the HR responses induced by all three different intensities of loads: low (30 W: correlation coefficient, r = 0.68 +/- 0.13, mean +/- SD), moderate (75 W: r = 0.93 +/- 0.07) and high (125 W: r = 0.97 +/- 0.02). The first-order exponential curve fitted only the moderate load response. Although the second-order exponential equation fitted the HR response for both the moderate and high loads, the equation did not fit the low-load response (r = 0.43 +/- 0.26). In low-load exercise, the sum of the power of the residuals for the exponential hyperbolic sine curve fitting was significantly smaller than that for the first- or second-order exponential curve fitting. In conclusion, the exponential hyperbolic sine function is useful for quantitative analyses of the HR response to exercise loads of various intensities.


Assuntos
Frequência Cardíaca/fisiologia , Modelos Cardiovasculares , Esforço Físico/fisiologia , Adulto , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Cinética , Análise dos Mínimos Quadrados , Masculino
14.
Anat Embryol (Berl) ; 201(6): 455-66, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10909899

RESUMO

The closure of the neural tube (NT) in the human embryo has generally been described as a continuous process that begins at the level of the future cervical region and proceeds both rostrally and caudally. On the other hand, multiple initiation sites of NT closure have been demonstrated in mice and other animals. In humans, based on the study of neural tube defects (NTD) in clinical cases, van Allen et al. (1993) proposed a multisite NT closure model in which five closure sites exist in the NT of human embryos. In the present study, we examined human embryos in which the NT was closing (Congenital Anomaly Research Center, Kyoto University) grossly and histologically, and found that NT closure in human embryos initiates at multiple sites but that the mode of NT closure in humans is different from that in many other animal species. In addition to the future cervical region that is widely accepted as an initiation site of NT closure (Site A), the mesencephalic-rhombencephalic boundary was found to be another initiation site (Site B). The second closure initiating at Site B proceeds bidirectionally and its caudal extension meets the first closure from Site A over the rhombencephalon, and the rostral extension of the second closure meets another closure extending from the rostral end of the neural groove (Site C) over the prosencephalon, where the anterior neuropore closes. The caudal extension of the first closure initiating at Site A was found to proceed all the way down to the caudal end of the neural groove where the posterior neuropore is formed, indicating that in humans, NT closure does not initiate at the caudal end of the neural groove to proceed rostrally. Since there is a considerable species difference in the mode of NT closure, we should be careful when extrapolating the data from other animals to the human. It seems that the type of NTD affects the intrauterine survival of abnormal embryos. Almost all the embryos with total dysraphism appear to die by 5 weeks of gestation, those with an opening over the rhombencephalon by 6.5 weeks, and those with a defect at the frontal and parietal regions survive beyond 7 weeks.


Assuntos
Sistema Nervoso Central/anormalidades , Embrião de Mamíferos/anormalidades , Embrião de Mamíferos/patologia , Defeitos do Tubo Neural/etiologia , Defeitos do Tubo Neural/patologia , Fatores Etários , Animais , Feminino , Humanos , Camundongos , Modelos Biológicos , Gravidez , Coelhos
15.
Life Sci ; 66(3): 229-34, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10665998

RESUMO

Anacardic acids are one of natural products found in not only the cashew nut shell oil but also the nut and fruit juice. The present study was conducted to investigate the uncoupling effect of anacardic acids on oxidative phosphorylation of rat liver mitochondria using succinate (plus rotenone) as a substrate. Four anacardic acids with C15:0, C15:1, C15:2 or C15:3 as an alkyl side chain exhibited uncoupling effects similar to the classical uncoupler, 2,4-dinitrophenol on ADP/O ratio, state 4 and respiratory control ratio (RCR). Anacardic acid with C15:1 side chain was most effective for uncoupling of these compounds. Salicylic acid, which has no alkyl side chain, exhibited a very weak uncoupling effect on oxidative phosphorylation. When the carboxyl group in anacardic acids was lost converting them to the corresponding cardanols, uncoupling activity dramatically decreased regardless of the number of double bonds in the long alkyl chain. These results suggest that the C15 alkyl side chain as well as the carboxyl group may play an important role in assisting the uncoupling activity of anacardic acids in liver mitochondria of animals. This study provides the first evidence of an uncoupling effect of anacardic acids on liver mitochondria


Assuntos
Ácidos Anacárdicos , Mitocôndrias Hepáticas/efeitos dos fármacos , Nozes/química , Fosforilação Oxidativa/efeitos dos fármacos , Salicilatos/farmacologia , Desacopladores/farmacologia , 2,4-Dinitrofenol/farmacologia , Animais , Técnicas In Vitro , Masculino , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
16.
J Cardiovasc Pharmacol Ther ; 5(3): 183-91, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11150407

RESUMO

BACKGROUND: Heart-rate (HR) variability is an important predictor of mortality in patients with heart disease. We examined the effects of cilostazol, a quinolinone derivative, on HR and HR variability in patients with chronic atrial fibrillation associated with bradycardia episodes. PATIENTS AND METHODS: Thirteen patients with chronic atrial fibrillation associated with bradycardia episodes (minimal HR <40/min and/or pauses, ie, episodes with an RR interval > 2.5 sec) received cilostazol (100 or 200 mg/day) orally for at least 2 months and 24-hour Holter electrocardiography was performed before and after the start of cilostazol administration. RESULTS: Minimal HR was significantly increased, by an average of 14 beats/min (bpm), at 3.3 +/- 0.8 weeks (mean +/- SD) after the start of cilostazol treatment. The number of pauses was significantly decreased. As a consequence, mean HR was increased by an average of 18 bpm. Maximal HR was also increased by an average of 19 bpm. The circadian variation of the HR, determined by cosine fitting, was not changed by cilostazol treatment. The time-domain HR variabilities, ie, the SD of the mean RR interval and the SD of the 5-minute mean RR intervals, were also unchanged. New York Heart Association functional class was significantly improved and the plasma atrial natriuretic polypeptide level was significantly decreased after the initiation of cilostazol treatment. CONCLUSION: Cilostazol improves the slow HR episodes associated with chronic atrial fibrillation and maintains the HR circadian variation and time-domain variability, indicating that cilostazol has therapeutic utility for the treatment of the slow HR associated with chronic atrial fibrillation.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Fator Natriurético Atrial/efeitos dos fármacos , Bradicardia/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Tetrazóis/farmacologia , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/sangue , Fator Natriurético Atrial/sangue , Bradicardia/sangue , Cilostazol , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Fosfodiesterase/uso terapêutico , Estatísticas não Paramétricas , Tetrazóis/uso terapêutico
17.
J Nutr Sci Vitaminol (Tokyo) ; 45(3): 239-49, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10524344

RESUMO

26,27-Hexafluoro-1 alpha,25-dihydroxyvitamin D3 [F6-1,25-(OH)2D3] is more potent than 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] in stimulating bone resorption in vitro and in vivo. The reason why F6-1,25(OH)2D3 is more active remains unclear. To clarify the relationship between the bone-resorbing activity of each vitamin D3 analogue and the metabolism of each analogue, in the present study, we used an ex vivo method that was established by Reynolds et al (Calcif Tissue Res, 1974, 15, 333-339). The effect of F6-1,25(OH)2D3 or 1,25(OH)2D3 on 45Ca release from parietal bones, prepared at 3, 14 and 24 h after injection of 1.9, 3.8, 7.6 or 15.2 pmol vitamin D analog/g body weight, was examined. F6-1,25(OH)2D3 was more potent than 1,25(OH)2D3 during each in vivo time period. 1,25(OH)2D3 at 3 h after the injection was more active compared to the control (no injection of 1,25(OH)2D3) but not at 14 and 24 h. The radioactivity of the bones after the injection of [3H]-F6-1,25(OH)2D3 was retained even at 24 h. In the case of [3H]-1,25(OH)2D3, the radioactivity of bones decreased with an increase in the in vivo period. In a HPLC analysis of the lipid extract of bone homogenate, [3H]-F6-1,25(OH)2D3 alone was detected at 3 h after the injection and both [3H]-F6-1,25(OH)2D3 and [3H]-26,27-hexafluoro-1 alpha, 23S,25-trihydroxyvitamin D3 [F6-1,23,25(OH)3D3] were detected at 14 and 24 h after the injection. [3H]-1,25(OH)2D3 was highly detected at 3 h after the injection, but it decreased with an increase in the in vivo period. In the ex vivo test, the activity of F6-1,23,25(OH)3D3 was less than that of F6-1,25(OH)2D3 but similar to that of 1,25(OH)2D3. The present study indicates that F6-1,25(OH)2D3 is more active and more long-lasting than 1,25(OH)2D3 in the ex vivo method. A higher potency of F6-1,25(OH)2D3 is explained, at least partly, by the results that the amounts of both F6-1,25(OH)2D3 and its active metabolite, F6-1,23,25(OH)3D3, in the bones are higher than that of 1,25(OH)2D3, and that F6-1,25(OH)2D3 and its metabolite are retained in bones longer than 1,25(OH)2D3.


Assuntos
Reabsorção Óssea , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Animais , Animais Recém-Nascidos/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Calcitriol/administração & dosagem , Calcitriol/farmacocinética , Radioisótopos de Cálcio/metabolismo , Cromatografia Líquida de Alta Pressão , Cinética , Camundongos , Trítio
18.
Neurotoxicol Teratol ; 21(5): 603-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10492395

RESUMO

This study examined the effect of two high doses (3 or 6 mg/kg/day) of nicotine administrations via injections to pregnant rats on the dopaminergic, serotonergic, and noradrenergic systems in six brain regions in young adult male rats. The 3 mg/kg/day and 6 mg/kg/ day nicotine exposure resulted in significant decreases in dihydroxyphenylacetic acid (DOPAC) content in the neocortex and in both the neocortex and in the midbrain plus pons medulla, respectively, without any effects on the other brain regions such as the hypothalamus or striatum. No significant effects of prenatal nicotine were found on norepinephrine, serotonin, or 5-hydroxy-3-indolacetic acid levels. These data demonstrated that prenatal nicotine induced disturbances in the dopaminergic system in the young adult period. Furthermore, the region-specific reductions in the DOPAC content suggests that the exposure to a high dose of nicotine in utero might cause a predisposition to diseases related to a dopaminergic dysfunction in the frontal cortex.


Assuntos
Dopamina/metabolismo , Estimulantes Ganglionares/efeitos adversos , Neocórtex/efeitos dos fármacos , Nicotina/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Monoaminas Biogênicas/metabolismo , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Feminino , Estimulantes Ganglionares/administração & dosagem , Masculino , Neocórtex/metabolismo , Nicotina/administração & dosagem , Gravidez , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
20.
Biochemistry ; 38(24): 7630-7, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10387002

RESUMO

Tropinone reductase-II (TR-II) catalyzes the NADPH-dependent reduction of the carbonyl group of tropinone to a beta-hydroxyl group. The crystal structure of TR-II complexed with NADP+ and pseudotropine (psi-tropine) has been determined at 1.9 A resolution. A seven-residue peptide near the active site, disordered in the unliganded structure, is fixed in the ternary complex by participation of the cofactor and substrate binding. The psi-tropine molecule is bound in an orientation which satisfies the product configuration and the stereochemical arrangement toward the cofactor. The substrate binding site displays a complementarity to the bound substrate (psi-tropine) in its correct orientation. In addition, electrostatic interactions between the substrate and Glu156 seem to specify the binding position and orientation of the substrate. A comparison between the active sites in TR-II and TR-I shows that they provide different van der Waals surfaces and electrostatic features. These differences likely contribute to the correct binding mode of the substrates, which are in opposite orientations in TR-II and TR-I, and to different reaction stereospecificities. The active site structure in the TR-II ternary complex also suggests that the arrangement of the substrate, cofactor, and catalytic residues is stereoelectronically favorable for the reaction.


Assuntos
Oxirredutases do Álcool/química , Datura stramonium/enzimologia , NADP/química , Plantas Medicinais , Plantas Tóxicas , Tropanos/química , Sítios de Ligação , Catálise , Simulação por Computador , Cristalografia por Raios X , Dimerização , Substâncias Macromoleculares , Modelos Moleculares , Isoformas de Proteínas/química , Estereoisomerismo , Especificidade por Substrato
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