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1.
Zhonghua Fu Chan Ke Za Zhi ; 58(11): 833-837, 2023 Nov 25.
Artigo em Zh | MEDLINE | ID: mdl-37981769

RESUMO

Objective: To investigate the relationship between subchorionic hematoma (SCH) and coagulation status, autoantibodies, and conception method. Methods: A total of 100 pregnant women diagnosed with SCH from June 2020 to December 2021 in the Third Affiliated Hospital of Zhengzhou University were included in the SCH group, while 100 healthy pregnant women during the same period were selected as the control group. The coagulation status (including platelet, prothrombin time, thrombin time, activated partial thromboplastin time, fibrinogen, antithrombin Ⅲ, fibrin degradation products, D-dimer, homocysteine, protein S activity, protein C activity), the positive rate of autoantibodies [including antiphospholipid antibodies (anticardiolipin antibody and anti-ß2 glycoprotein Ⅰ antibody), antinuclear antibody] and the mode of conception of the two groups were analyzed. Results: Compared to the control group, the SCH group had higher levels of platelet [(240±45)×109/L vs (227±37)×109/L], fibrinogen [(4.0±0.8) vs (3.6±0.7) g/L], D-dimer [(0.42±0.18) vs (0.31±0.15) mg/L], blood homocysteine [(8.9±4.2) vs (6.9±2.3) µmol/L], and lower level of protein S activity [(55±14)% vs (68±20)%], and there were significant differences between the two groups (all P<0.05). The SCH group had higher positive rates of autoantibodies [24.0% (24/100) vs 8.0% (8/100)], antiphospholipid antibodies [15.0% (15/100) vs 6.0% (6/100)], anti-ß2 glycoprotein Ⅰ antibody [10.0% (10/100) vs 3.0% (3/100)], antinuclear antibody [11.0% (11/100) vs 2.0% (2/100)] and assisted reproduction rate [10.0% (10/100) vs 2.0% (2/100)] than those of the control group (all P<0.05). Conclusion: The occurrence of SCH is related to blood hypercoagulability, positive autoantibodies, and assisted reproduction.


Assuntos
Anticorpos Antinucleares , Autoanticorpos , Gravidez , Feminino , Humanos , Anticorpos Antifosfolipídeos , Fibrinogênio , Homocisteína , Glicoproteínas
2.
Zhonghua Fu Chan Ke Za Zhi ; 55(2): 112-119, 2020 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-32146740

RESUMO

Objective: To investigate the surgical complications in the treatment of stage Ⅰ endometrial cancer by robotic-assisted laparoscopy, the risk degree of Clavein-Dindo complications and the main risk factors affecting the occurrence of surgical complications. Methods: A retrospective case-control study was conducted in the First Affiliated Hospital of Zhengzhou University from October 2014 to June 2019. The patients were divided into robotic-assisted laparoscopy group and traditional laparoscopy group according to the operation mode, including 131 cases in robot group and 290 cases in traditional laparoscopy group. To compare the complications during and after operation and the risk degree of complications between the two groups by Clavein-Dindo classification standard, the age, body mass index (BMI), comorbidities, past history of pelvic surgery, American Society of Anesthesiologists (ASA) grade, preoperative anemia, number of pelvic lymph node resection, number of abdominal aortic lymph node resection, the total number of lymph node resection, operation time, surgical methods (robot surgery or traditional laparoscopic surgery) and other clinicopathological data were analyzed by logistic regression analysis. Results: (1) Complications of operation: the incidence of operative complications (including intraoperative and postoperative complications) in robot group was significantly lower than that in traditional laparoscopy group [(20.6%, 27/131) vs (34.8%, 101/290); χ(2)=8.620, P=0.003)]. The incidence of intraoperative complications in robot group was lower than that in traditional laparoscopy group [1.5% (2/131) vs 6.2% (18/290); χ(2)=4.368, P=0.037]. The incidence of intraoperative vascular injury in robot group was significantly lower than that in traditional laparoscopy group [0.8% (1/131) vs 5.2% (15/290); χ(2)=4.798, P=0.022]. The incidence of postoperative complications in robot group was also lower than that in traditional laparoscopy group [19.1% (25/131) vs 28.6% (83/290); χ(2)=4.303, P=0.038], but the incidence of postoperative lymphatic leakage in robot group was higher than that in traditional laparoscopy group [10.7% (14/131) vs 5.2% (15/290); χ(2)=4.279, P=0.039]. (2) Clavein-Dindo classification: the incidence of Clavein-Dindo Ⅰ, Ⅲ, Ⅲ, Ⅳ and Ⅴ grade between two groups were respectively 3.8% (5/131) vs 11.0% (32/290), 13.7% (18/131) vs 14.5% (42/290), 3.1% (4/131) vs 8.6% (25/290), 0 (0/131) vs 0.3% (1/290), 0 (0/131) vs 0.3% (1/290), and the incidence of grade Ⅰ (χ(2)=5.684, P=0.015) and Ⅲ (χ(2)=4.361, P=0.037) complications were statistically significant. The incidence of severe complications in robot group (grade Ⅲ and above) was lower than that in traditional laparoscopy group [3.1% (4/131) vs 9.3% (27/290); χ(2)=5.179, P=0.023]. (3) Analysis of influencing factors of surgical complications: univariate analysis showed that BMI (χ(2)=15.801, P=0.000), preoperative anemia (χ(2)=14.299, P=0.000), total number of lymph node resection (χ(2)=10.425, P=0.001), surgical methods (χ(2)=8.620, P=0.003) were related to the occurrence of surgical complications of endometrial carcinoma. Multivariate analysis showed that BMI (OR=0.289, 95%CI: 0.097-0.864, P=0.026), preoperative anemia (OR=0.309, 95%CI: 0.129-0.740, P=0.008), the total number of lymph node resection (OR=0.624, 95%CI: 0.403-0.966, P=0.034) and surgical methods (OR=3.491, 95%CI: 1.030-11.840, P=0.045) were independent risk factors for surgical complications of endometrial carcinoma. Conclusions: Compared with traditional laparoscopic surgery, robot-assisted laparoscopic surgery has fewer complications and lower incidence of severe complications. BMI, preoperative anemia, the total number of lymph node resection and surgical methods are independent risk factors for the occurrence of surgical complications of stage Ⅰ endometrial cancer.


Assuntos
Neoplasias do Endométrio/cirurgia , Laparoscopia , Excisão de Linfonodo/métodos , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Estudos de Casos e Controles , China/epidemiologia , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/patologia , Feminino , Humanos , Incidência , Estudos Retrospectivos , Fatores de Risco , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento
3.
Biochim Biophys Acta ; 1533(3): 220-32, 2001 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-11731332

RESUMO

Fenofibrate is a potent hypolipidemic agent that lowers plasma lipid levels and may thus decrease the incidence of atherosclerosis. Here we investigated the molecular mechanism of fenofibrate's hypolipidemic action by characterizing its in vivo effects on the expression of mRNAs and the activities of pivotal enzymes in cholesterol and triglyceride metabolism in the hamster. Treatment of hamsters with fenofibrate led to a dose-dependent reduction in serum cholesterol concentrations. Studies on the incorporation of [(14)C]acetate and [(14)C]mevalonate into cholesterol suggested that this effect occurs primarily through inhibition of cholesterol biosynthesis at steps prior to mevalonate. Fenofibrate decreased levels of hepatic enzyme activities and mRNAs for 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) synthase and HMG CoA reductase. A potential mechanism for transcriptional regulation of these enzymes is via SREBP-2 that we found to be suppressed 2-fold by fenofibrate. Fenofibrate also lowered circulatory triglyceride levels. In keeping with the effect, we observed strong suppression of fatty acid synthase, acetyl-CoA carboxylase and apolipoprotein C-III mRNA and stimulation of lipoprotein lipase and acyl-CoA oxidase mRNA in the liver of fenofibrate-treated hamsters. These observations suggest that the effect of fenofibrate on triglyceride metabolism is likely to be a result of both decreased fatty acid synthesis and increased lipoprotein lipase and acyl-CoA oxidase gene expression in the liver. Surprisingly, alterations in lipoprotein lipase, acyl-CoA oxidase, acetyl-CoA carboxylase, and apolipoprotein C-III could not be observed in hamster hepatocytes incubated with fenofibric acid in vitro. These observations raise the possibility that changes in these genes may be secondary to the metabolic alterations occurring in animals but not in cultured cells and thus that the effect of fenofibrate on these genes may be indirect.


Assuntos
Fenofibrato/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos , Fígado/efeitos dos fármacos , Animais , Células Cultivadas , Colesterol/biossíntese , Colesterol/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Cricetinae , Relação Dose-Resposta a Droga , Regulação para Baixo , Hidroximetilglutaril-CoA Sintase , Lipídeos/sangue , Fígado/metabolismo , Masculino , Mesocricetus , Modelos Animais , RNA Mensageiro/análise
4.
Arterioscler Thromb Vasc Biol ; 21(1): 115-21, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145942

RESUMO

Inhibitors of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase, such as simvastatin, lower circulating cholesterol levels and prevent myocardial infarction. Several studies have shown an unexpected effect of HMG-CoA reductase inhibitors on inflammation. Here, we confirm that simvastatin is anti-inflammatory by using a classic model of inflammation: carrageenan-induced foot pad edema. Simvastatin administered orally to mice 1 hour before carrageenan injection significantly reduced the extent of edema. Simvastatin was comparable to indomethacin in this model. To determine whether the anti-inflammatory activity of simvastatin might affect atherogenesis, simvastatin was tested in mice deficient in apoE. Mice were dosed daily for 6 weeks with simvastatin (100 mg/kg body wt). Simvastatin did not alter plasma lipids. Atherosclerosis was quantified through the measurement of aortic cholesterol content. Aortas from control mice (n=20) contained 56+/-4 nmol total cholesterol/mg wet wt tissue, 38+/-2 nmol free cholesterol/mg, and 17+/-2 nmol cholesteryl ester/mg. Simvastatin (n=22) significantly (P<0.02) decreased these 3 parameters by 23%, 19%, and 34%, respectively. Histology of the atherosclerotic lesions showed that simvastatin did not dramatically alter lesion morphology. These data support the hypothesis that simvastatin has antiatherosclerotic activity beyond its plasma cholesterol-lowering activity.


Assuntos
Anti-Inflamatórios/farmacologia , Anticolesterolemiantes/farmacologia , Arteriosclerose/patologia , Arteriosclerose/prevenção & controle , Colesterol/metabolismo , Sinvastatina/metabolismo , Administração Oral , Animais , Anti-Inflamatórios/administração & dosagem , Anticolesterolemiantes/administração & dosagem , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Arteriosclerose/sangue , Arteriosclerose/metabolismo , Carragenina/administração & dosagem , Colesterol/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Membro Posterior/patologia , Injeções Subcutâneas , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sinvastatina/administração & dosagem
5.
Eur J Pharmacol ; 427(3): 285-93, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11567659

RESUMO

Dyslipidemia, a major risk factor for cardiovascular disease, may be directly linked to diabetic hyperglycemia and insulin resistance. An appropriate dyslipidemic animal model that has diabetes would provide an important tool for research on the treatment of diabetic dyslipidemia. Ten days of high fat feeding in golden Syrian hamsters resulted in a significant increase in insulin resistance and baseline serum lipid levels accompanied by a pronounced dyslipidemia. Thirteen days of treatment with fenofibrate, a peroxisome proliferator-activated receptor alpha (PPARalpha) selective agonist, produced a dose-dependent decrease in serum lipid levels. The pattern observed was characterized by lowered very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) and raised high-density lipoprotein (HDL) cholesterol in a fashion similar to that seen in man. Diabetic conditions were also significantly improved by fenofibrate with a normalization of impaired glucose tolerance and an improvement of insulin sensitivity during an oral glucose tolerance test. These data suggest that fenofibrate may correct not only the dyslipidemia but also the insulin resistance caused by a high fat diet, and the high fat fed hamster may be a good animal model for research on the treatment of diabetic dyslipidemia with PPARalpha selective agonists.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Gorduras na Dieta/administração & dosagem , Fenofibrato/farmacologia , Hiperlipidemias/prevenção & controle , Hipolipemiantes/farmacologia , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , VLDL-Colesterol/sangue , VLDL-Colesterol/efeitos dos fármacos , Cricetinae , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ácidos Graxos/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/genética , Hiperlipidemias/sangue , Hiperlipidemias/induzido quimicamente , Insulina/sangue , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Mesocricetus , Oxirredução/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/agonistas , Fatores de Transcrição/agonistas
6.
Chronobiol Int ; 13(3): 213-25, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8874984

RESUMO

Time-dependent variations in the pharmacokinetics and pharmacodynamics of insulin were studied at two times, 10:30 and 20:30 during the same day in normal and streptozotocin (STZ)-induced diabetic minipigs housed in L(06:00):D(18:00) using the intravenous insulin tolerance test. Following intravenous insulin (0.1 IU/kg) administration in normal minipigs, the time for the glucose level to reach nadir (tnadir) was significantly longer in the evening than the morning [(A.M.; 30.4 (+/- 2.4) vs. P.M.: 38.5 (+/- 3.3) min] (p < 0.01), although maximum reduction of glucose level (nadir) in the morning and evening was not significantly different [A.M.: (-70 (+/- 2) vs. P.M.: -65 (+/- 5) %]. The rate of glucose decline (Kin) was significantly decreased in the evening [A.M.: 5.33 (+/- 0.71) vs. P.M.: 4.44 (+/- 0.54) %dBG/min] (p < 0.01), and the integrated glucose-lowering response (ABCB) was significantly higher in the evening than the morning [A.M.: 3.18 (+/- 0.38) vs. P.M.: 4.52 (+/- 0.30) (g/dl)* min] (p < 0.01). The area under the plasma insulin concentration curve was increased significantly in the evening [A.M.: 2.26 (+/- 0.174) vs. P.M.: 2.74 (+/- 0.18) (mU/ml)* min], while the morning plasma insulin half-life did not differ significantly from that in the evening [A.M.: 4.79 (+/- 0.36) vs. P.M.: 5.47 (+/- 0.47) min]. After induction of diabetes by intravenous STZ injections, minipigs became diabetic, baseline blood glucose was observed to increase from the range of 45-55 to 200-250 mg/dl while plasma insulin levels decreased from 7-12 to 3-5 uU/ml. In the STZ-induced diabetic minipigs, a higher dose (0.2 IU/kg) was used in the intravenous insulin tolerance test in an attempt to normalize the high glucose levels. Following intravenous administration of insulin, the evening Kin and ABCB were significantly higher than they were in the morning [Kin = A.M.: 0.99 (+/- 0.25) vs. P.M.: 1.75 (+/- 0.44) %dBG/min (p < 0.01); ABCB = A.M.: 12.63 (+/- 1.91) vs. P.M.: 19.09 (+/- 5.43) (g/dl)* min (p < 0.01)]. However, there was no significant difference between tnadir and nadir values obtained in the morning and evening [tnadir = A.M.: 81.4 (+/- 9.2) vs. P.M.: 92.8 (+/- 13.7) min; nadir = A.M.: 39.6 (+/- 5.2) vs P.M.: 48.0 (+/- 9.0) %]. The pharmacodynamics and pharmacokinetics of IV insulin both were found to be highly dose-dependent (r > 0.90).


Assuntos
Glicemia/metabolismo , Ritmo Circadiano , Diabetes Mellitus Experimental/fisiopatologia , Insulina/sangue , Insulina/farmacologia , Porco Miniatura/fisiologia , Animais , Glicemia/efeitos dos fármacos , Escuridão , Diabetes Mellitus Experimental/sangue , Meia-Vida , Insulina/farmacocinética , Cinética , Luz , Valores de Referência , Suínos
7.
J Oral Sci ; 40(4): 153-7, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10036828

RESUMO

In the atrioventricular canal (AVC) and outflow tract (OT) of the developing heart, endothelial cells transform specifically to mesenchymal cells. The mesenchymal cells migrate into the underlying acellular matrix termed cardiac jelly and form endocardial cushion tissue. It is believed the that the highly hydrated nature of cardiac jelly is ascribed to sulfated glycoconjugates in the components of jelly matrix. In the present study, we have visualized the distribution and its temporal changes of sulfated glycoconjugates in the embryonic heart from stage 12 to 26 using whole mount alcian blue (AB) histochemistry. Atrial matrix was AB-negative in all the stages examined. Cardiac jelly in the AVC and OT were positive and the staining intensity increased as heart development proceeded, while AB-positive staining in the matrix of the ventricle became negative by stage 19. At stages later than 19, AB-positive matrix was localized in only the AVC and OT where endothelially-derived mesenchymal cells populated.


Assuntos
Glicoconjugados/metabolismo , Coração/embriologia , Miocárdio/metabolismo , Sulfatos/metabolismo , Azul Alciano , Animais , Embrião de Galinha , Corantes , Mesoderma/citologia , Mesoderma/metabolismo , Fatores de Tempo
8.
J Nippon Med Sch ; 68(4): 301-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11505277

RESUMO

Thy-1 nephritis was induced in stroke-prone spontaneously hypertensive rats (SHR-SP) with unilateral nephrectomy (UNX) and normotensive same genetic strain Wistar-Kyoto (WKY) rats with UNX to evaluate whether the tubulointerstitial injury in Thy-1 nephritis is accelerated by long-term systemic and intraglomerular hypertension. SHR-SP that underwent UNX at twelve weeks of age were randomly assigned to receive monoclonal anti-thy 1.1 antibody (group SP), and normal saline (group SC). Age-matched normotensive WKY rats served as controls and were given the same dose of monoclonal anti-thy 1.1 antibody after UNX (group WK). In all groups, the blood pressure and renal function were assessed, and morphologic changes of tubulointerstitium were examined by using immunohistochemistry and light microscopy twelve weeks after Thy-1 nephritis induction (in groups SP and WK) and UNX alone (in group SC). In all groups, histological findings, the degree of monocyte/macrophage infiltration, interstitial expression of alpha-smooth muscle actin (alpha-SMA), which is a marker for myofibroblasts, and the degree of tubular cell proliferation were examined. In addition, assessments of blood pressure, serum creatinine and BUN levels, and the degree of proteinuria were made. In parallel to glomerular structural damage, interstitial fibrosis with predominant monocyte/macrophage influx, increased interstitial expression of alpha-SMA and tubular cell proliferation were observed in group SP. A significant increase in serum creatinine and proteinuria were also present in this group. In contrast, the changes observed in group SC were not so evident or extensive as in group SP. The level of proteinuria was lower than that in group SP. No evident tubulointerstitial changes were found in group WK. The results showed that tubulointerstitial injury was prominently progressed in the hypertensive model with Thy-1 nephritis. This suggests that sustained systemic and glomerular hypertension is not only ultimately responsible for the progression of immunologically mediated glomerular injury, but is also responsible for subsequent tubulointerstitial changes. Migration and proliferation of myofibroblasts and intense influx of monocytes/macrophages may contribute to the development of tubulointerstitial fibrosis.


Assuntos
Hipertensão/complicações , Nefrite Intersticial/etiologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Túbulos Renais/patologia , Macrófagos/patologia , Monócitos/patologia , Nefrectomia , Nefrite Intersticial/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
11.
J Pharmacol Exp Ther ; 315(2): 688-95, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16027230

RESUMO

The enzyme dipeptidyl peptidase-IV (DPP-4) inactivates the incretin hormone glucagon-like peptide-1 (GLP-1). Because GLP-1 has therapeutic effects in patients with type 2 diabetes, but its potential is limited by a short half-life, DPP-4 inhibition is a promising approach to diabetes treatment. This study examined acute (single dose) and chronic (once-a-day dosing for 21 days) effects of the DPP-4 inhibitor vildagliptin (0.03-10 mg/kg) on plasma DPP-4 activity, intact GLP-1, glucose, and insulin after an oral glucose load in insulin-resistant Zucker fatty rats and acute effects in mildly insulin-resistant high-fat-fed normal rats. A single oral dose of vildagliptin in Zucker rats produced a rapid and dose-related inhibition of DPP-4: the minimum effective dose (MED) was 0.3 mg/kg. Glucose-induced increases of intact GLP-1 were greatly but similarly enhanced by vildagliptin at doses > or =0.3 mg/kg. Postload glucose excursions decreased, and the insulinogenic index (Deltainsulin/Deltaglucose at 10 min) increased, with an MED of 0.3 mg/kg and a maximally effective dose of 3 mg/kg. The effects of vildagliptin after chronic treatment were nearly identical to those of acute administration, and vildagliptin had no effect on body weight. In fat-fed normal rats, vildagliptin (3 mg/kg) also decreased postload glucose excursions and increased the insulinogenic index, but these effects were smaller than those in Zucker rats. Thus, vildagliptin is an orally effective incretin enhancer with antihyperglycemic activity in insulin-resistant rats and exhibits no tachyphylaxis. GLP-1-mediated augmentation of glucose-induced insulin release seems to make the major contribution to the antidiabetic properties of vildagliptin.


Assuntos
Adamantano/análogos & derivados , Resistência à Insulina/fisiologia , Adamantano/farmacologia , Animais , Área Sob a Curva , Glicemia/metabolismo , Gorduras na Dieta/efeitos adversos , Dipeptidil Peptidase 4/sangue , Relação Dose-Resposta a Droga , Peptídeo 1 Semelhante ao Glucagon/sangue , Intolerância à Glucose/fisiopatologia , Glucose Oxidase , Teste de Tolerância a Glucose , Resistência à Insulina/genética , Masculino , Nitrilas , Pirrolidinas , Ratos , Ratos Zucker , Taquifilaxia/fisiologia , Fatores de Tempo , Vildagliptina , Aumento de Peso/efeitos dos fármacos
12.
Se Pu ; 17(6): 556-8, 1999 Nov.
Artigo em Zh | MEDLINE | ID: mdl-12552690

RESUMO

This article reports a successful example that an injected sample is simultaneously introduced into two fused silica capillary columns and detected separately by a flame ionization detector (FID) and an HP 5973 mass selective detector (MSD) both installed on an HP 6890 Gas Chromatograph. This GC and GC/MS analyses of aromatic hydrocarbons in oils and rock extracts were carried out by using this method and good results were achieved. This method is of great value in organic geochemistry research because it is efficient and economical.

13.
Se Pu ; 19(4): 304-8, 2001 Jul.
Artigo em Zh | MEDLINE | ID: mdl-12545486

RESUMO

Light hydrocarbon analytical method of "PTV with Back Flushing" presented here is characterized as follows: a) with "PTV" inlets temperature programmed; b) with gas line system of "Back Flushing"; c) with direct injection of oil samples. After oil sample injection, "Back Flushing" is on when light hydrocarbon components enter into analytical chromatographic column. At the same time, the temperature of inlet increases. The high temperature and "Back Flushing" blow the heavy components in the oil samples out of the analytical system. Besides, the analytical method of "Head Space" was established. Both "PTV with Back Flushing" and "Head Space" have the advantages of long column life and short analysis time. The resolution for lighter components < C9 meets the criterion of ASTM D5134-98, with the good repeatability. Ten oil samples from 6 oil areas were analysed by using the two methods. The relative deviations between the two analytical results represented by 19 geochemistry parameters were about +/- (1%-25%). The reasons for the deviation are discussed. It is pointed out that in geochemistry study it is not acceptable to combine the data obtained from two analytical methods. The analytical results obtained by injecting crude oil directly into injector are more reliable. The results obtained in "Head Space" analytical method should be calibrated when used in geochemistry study.

14.
J Pharmacokinet Biopharm ; 17(5): 551-70, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2614685

RESUMO

Myocardial contractility of normotensive and spontaneously hypertensive rabbits was determined following an iv bolus injection of propranolol HCl. Left ventricular pressure and dimension were used to calculate the contractility parameters of (dP/dt)max, maximum fiber shortening velocity (Vcf), and the slope of the end systolic pressure-end systolic volume line (ESP-ESV line). Hypertension was induced by a methoxamine HCl iv infusion which mimicked the cardiac effects seen in essential hypertension. Propranolol caused a significant decrease in all contractility parameters (p less than 0.05) within 15 min after administration, with a peak effect occurring after 30-35 mins. The pharmacokinetics and pharmacodynamics of propranolol were fit using Hill's equation in conjunction with the concentration of drug in the theoretical effect compartment. The normotensive group of rabbits had a calculated EC(50) of 12.7 ng/ml, while the hypertensive group had an EC(50) of 6.9 ng/ml, indicating that the hypertensive rabbits were much more sensitive to the propranolol than the normotensive group. In addition, the normotensive group of rabbits demonstrated a much different pharmacokinetic-pharmacodynamic relationship than that of the hypertensive group, indicating that the hypertensive state of the animal has a significant effect upon the concentration-effect relationship.


Assuntos
Hipertensão/fisiopatologia , Contração Miocárdica/efeitos dos fármacos , Propranolol/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Propranolol/sangue , Propranolol/farmacocinética , Coelhos , Distribuição Tecidual
15.
Bioorg Med Chem Lett ; 8(21): 3087-92, 1998 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-9873681

RESUMO

The 3-pyridylethanolamine L-757,793 is a potent beta 3 AR agonist (EC50 6.3 nM, 70% activation) with 1,300- and 500-fold selectivity over binding to the beta 1 and beta 2 ARs, respectively. L-757,793 stimulated lipolysis in rhesus monkeys (ED50 0.2 mg/kg) with a maximum response equivalent to that elicited by isoproterenol.


Assuntos
Agonistas Adrenérgicos beta/síntese química , Receptores Adrenérgicos beta/efeitos dos fármacos , Sulfonamidas/síntese química , Agonistas Adrenérgicos beta/farmacologia , Animais , Cães , Humanos , Macaca mulatta , Masculino , Receptores Adrenérgicos beta 3 , Relação Estrutura-Atividade , Sulfonamidas/farmacologia
16.
Bioorg Med Chem Lett ; 9(5): 755-8, 1999 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-10201842
17.
Biochem Biophys Res Commun ; 279(2): 330-6, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11118287

RESUMO

11beta-hydroxysteroid dehydrogenase type 1 (11betaHSD1) is an enzyme that converts cortisone to the active glucocorticoid, cortisol. Cortisol-cortisone interconversion plays a key role in the regulation of glucose metabolism, since mice deficient in 11betaHSD1 are resistant to diet-induced hyperglycemia. Peroxisome proliferator activator receptors (PPAR) are key regulators of glucose and lipid homeostasis. We observed a striking downregulation of murine hepatic 11betaHSD1 expression and activity after chronic treatment of wild-type mice with PPARalpha agonists, while 11betaHSD1 in the livers of PPARalpha knockout mice, or in mice treated for only 7 h with PPARalpha agonists, was unaltered. Our results are the first to show PPARalpha agonists can affect glucocorticoid metabolism in the liver by altering 11betaHSD1 expression after chronic treatment. Regulation of active glucocorticoid levels in the liver by PPARalpha agonists may in turn affect glucose metabolism, consistent with reports of their antidiabetic effects.


Assuntos
Fenofibrato/farmacologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Hepatócitos/enzimologia , Hidroxiesteroide Desidrogenases/genética , Fígado/enzimologia , Proliferadores de Peroxissomos/farmacologia , Pirimidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Fatores de Transcrição/fisiologia , 11-beta-Hidroxiesteroide Desidrogenases , Animais , Células Cultivadas , Cricetinae , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Retroalimentação , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Knockout , Modelos Biológicos , RNA Mensageiro/genética , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/deficiência , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/agonistas , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos
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