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1.
Med J Malaysia ; 79(1): 47-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287757

RESUMO

INTRODUCTION: Several risk factors found to be associated with postoperative complications and cancer surgery, which carry a significant morbidity risk to cancer patients. Therefore, prehabilitation is necessary to improve the functional capability and nutritional status of a patient prior to surgery, so that the patient can withstand any postoperative activity and associated deterioration. Thus, this study aims to assess the effectiveness of prehabilitation interventions on the functional status of patients with gastric and oesophageal cancer who underwent esophagectomy and gastrectomy. MATERIAL AND METHODS: An interventional study was carried out among oesophageal and gastric cancer patients who had undergone surgery at the National Cancer Institute of Malaysia. The prehabilitation process took a maximum of two weeks, depending on the patient's optimisation before surgery. The prehabilitation is based on functional capacity (ECOG performance status), muscle function (handgrip strength), cardio-respiratory function (peak flow meter) and nutritional status (calorie and protein). Postoperative outcomes are measured based on the length of hospital stay, complications, and Clavien-Dindo Classification. RESULTS: Thirty-one patients were recruited to undergo a prehabilitation intervention prior to gastrectomy (n=21) and esophagectomy (n=10). Demographically, most of the cancer patients were males (67.7%) with an ideal mean of BMI (23.5±6.0). Physically, the majority of them had physical class (ASA grade) Grade 2 (67.7%), ECOG performance status of 1 (61.3%) and SGA grade B (51.6%). The functional capacity and nutritional status showed a significant improvement after one week of prehabilitation interventions: peak expiratory flow meter (p<0.001), handgrip (p<0.001), ECOG performance (p<0.001), walking distance (p<0.001), incentive spirometry (p<0.001), total body calorie (p<0.001) and total body protein (p=0.004). However, those patients who required two weeks of prehabilitation for optimization showed only significant improvement in peak expiratory flow meter (p<0.001), handgrip (p<0.001), and incentive spirometry (p<0.001). Prehabilitation is significantly associated postoperatively with the length of hospital stay (p=0.028), complications (p=0.011) and Clavien-Dindo Classification (p=0.029). CONCLUSION: Prehabilitation interventions significantly increase the functional capacity and nutritional status of cancer patients preoperatively; concurrently reducing hospital stays and complications postoperatively. However, certain cancer patients might require over two weeks of prehabilitation to improve the patient's functional capacity and reduce complications postoperatively.


Assuntos
Asma , Cuidados Pré-Operatórios , Masculino , Humanos , Idoso , Feminino , Apendicectomia , Força da Mão , Malásia , Complicações Pós-Operatórias/prevenção & controle
2.
Zhonghua Xue Ye Xue Za Zhi ; 44(8): 649-653, 2023 Aug 14.
Artigo em Chinês | MEDLINE | ID: mdl-37803838

RESUMO

Objective: To explore the efficacy and safety of Venetoclax combined with multidrug chemotherapy in patients with relapsed or refractory early T-cell precursor acute lymphoblastic leukemia (R/R ETP-ALL) . Methods: This study retrospectively analyzed 15 patients with R/R ETP-ALL who received Venetoclax combined with multidrug chemotherapy from December 2018 to February 2022. Among them, eight cases were combined with demethylated drugs, four cases were combined with demethylated drugs and HAAG chemotherapy regimen, two cases were combined with demethylated drugs and CAG regimen, and one case was combined with Cladribine. Specific usage and dosage of Venetoclax: 100 mg on day 1, 200 mg on day 2, 400 mg on day 3-28, orally; when combined with azole antifungal drugs, dosage was reduced to 100 mg/d. Results: Fifteen patients (10 males and 5 females) with R/R ETP-ALL were treated with Venetoclax and multidrug chemotherapy with a median age of 35 (12-42) years old. Of 4 refractory and 11 relapsed patients, the efficacy was evaluated on the 21th day following combined chemotherapy: the overall response rate, the complete response (CR) rate, and the CR with incomplete hematological recovery (CRi) rate were 67.7% (10/15), 60.0% (9/15), and 6.7% (1/15), respectively. For the overall study population, the 12-month overall survival (OS) rate was 60.0%, and the median OS was 17.7 months. The disease-free survival (DFS) rate of all CR patients at 12 months was 60.0%, and the median DFS did not reach. About 14 patients had Ⅲ-Ⅳ hematological toxicity, but these adverse reactions were all controllable. No adverse reaction in the nervous system and tumor lysis syndrome occurred in this study, and no adverse reaction of organs above grade Ⅲ occurred. Conclusion: Venetoclax combined with multidrug chemotherapy may be a safe and promising treatment option for patients with R/R ETP-ALL.


Assuntos
Leucemia Mieloide Aguda , Células Precursoras de Linfócitos T , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Masculino , Feminino , Humanos , Adulto , Estudos Retrospectivos , Resultado do Tratamento , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico
3.
Zhonghua Nei Ke Za Zhi ; 62(5): 520-525, 2023 May 01.
Artigo em Chinês | MEDLINE | ID: mdl-37096278

RESUMO

Objective: To assess the efficacy and cost-effectiveness of high-dose dual therapy compared with bismuth-containing quadruple therapy for treating Helicobacter pylori(H.pylori) infection in servicemen patients. Methods: A total of 160 H. pylori-infected, treatment-naive servicemen, including 74 men and 86 women, aged from 20 years to 74 years, with a mean (SD) age of 43 (13) years, tested in the First Center of Chinese PLA General Hospital from March 2022 to May 2022 were enrolled in this open-label, randomized controlled clinical trial. Patients were randomly allocated into 2 groups: the 14-day high-dose dual therapy group and the bismuth-containing quadruple therapy group. Eradication rates, adverse events, patient compliance, and drug costs were compared between the two groups. The t-test was used for continuous variables, and the Chi-square test for categorical variables. Results: No significant difference in H. pylori eradication rates were found between high-dose dual therapy and bismuth-containing quadruple therapy by ITT, mITT and PP analysis[ITT:90.0% (95%CI 81.2%-95.6%) vs. 87.5% (95%CI 78.2%-93.8%), χ2=0.25, P=0.617;mITT:93.5% (95%CI 85.5%-97.9%) vs. 93.3% (95%CI 85.1%-97.8%), χ2<0.01, P=1.000; PP: 93.5% (95%CI 85.5%-97.9%) vs. 94.5% (95%CI 86.6%-98.5%), χ2<0.01, P=1.000 ]. The dual therapy group exhibited significantly less overall side effects compared with the quadruple therapy group [21.8% (17/78) vs. 38.5% (30/78), χ2=5.15,P=0.023]. There were no significant differences in the compliance rates between the two groups [98.7%(77/78) vs. 94.9%(74/78), χ2=0.83,P=0.363]. The cost of medications in the dual therapy was 32.0% lower compared with that in the quadruple therapy (472.10 RMB vs. 693.94 RMB). Conclusions: The dual regimen has a favorable effect on the eradication of H. pylori infection in servicemen patients. Based on the ITT analysis, the eradication rate of the dual regimen is grade B (90%, good). Additionally, it exhibited a lower incidence of adverse events, better compliance and significantly reduced cost. The dual regimen is expected to be a new choice for the first-line treatment of H. pylori infection in servicemen but needs further evaluation.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Bismuto , Antibacterianos/uso terapêutico , Amoxicilina/efeitos adversos , Quimioterapia Combinada , Resultado do Tratamento , Inibidores da Bomba de Prótons/uso terapêutico
6.
Epidemiol Infect ; 148: e107, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32418555

RESUMO

Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for ESCC. Currently, the commonly used methods for P. gingivalis detection are culture or DNA extraction-based, which are either time and labour intensive especially for high-throughput applications. We aimed to establish and evaluate a rapid and sensitive direct quantitative polymerase chain reaction (qPCR) protocol for the detection of P. gingivalis without DNA extraction which is suitable for large-scale epidemiological studies. Paired gingival swab samples from 192 subjects undergoing general medical examinations were analysed using two direct and one extraction-based qPCR assays for P. gingivalis. Tris-EDTA buffer-based direct qPCR (TE-direct qPCR), lysis-based direct qPCR (lysis-direct qPCR) and DNA extraction-based qPCR (kit-qPCR) were used, respectively, in 192, 132 and 60 of these samples for quantification of P. gingivalis. The sensitivity and specificity of TE-direct qPCR was 95.24% and 100% compared with lysis-direct qPCR, which was 100% and 97.30% when compared with kit-qPCR; TE-direct qPCR had an almost perfect agreement with lysis-direct qPCR (κ = 0.954) and kit-qPCR (κ = 0.965). Moreover, the assay time used for TE-direct qPCR was 1.5 h. In conclusion, the TE-direct qPCR assay is a simple and efficient method for the quantification of oral P. gingivalis and showed high sensitivity and specificity compared with routine qPCR.


Assuntos
Reação em Cadeia da Polimerase/métodos , Porphyromonas gingivalis/isolamento & purificação , Técnicas Bacteriológicas , Humanos , Sensibilidade e Especificidade
8.
J Appl Microbiol ; 115(3): 756-65, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23725010

RESUMO

AIM: Aerobic CH4 oxidation is an important process controlling CH4 release from landfills to the atmosphere. The aim of this study was to investigate the link between CH4 oxidation activity and methanotrophs abundance and diversity in landfill cover soils of different age. METHODS AND RESULTS: Among the three investigated sites, the highest CH4 emission occurred at the active landfill area with the range of 1371-2242 mg m(-2)  day. The CH4 oxidation activities of landfill cover soils were 1·07-1·21 µmol g(-1)  h(-1) in the landfill area of 7-16 years, which was 7-17 times higher than those in the active landfill area. The relative abundance of methanotrophs assessed by quantification of pmoA gene was about 1·7 × 10(6) -2·4 × 10(7)  copies g(-1) in the landfill cover soils. The CH4 oxidation activity was positively correlated with pmoA copy number in the landfill cover soil of each site, respectively. Type II methanotrophs (Methylocystis) and type I methanotrophs including Methylosoma, Methylocaldum and Methylococcus were all present in the landfill cover soils. Compared to type I methanotroph, type II methanotroph, Methylocystis, was more abundant in the acidic landfill cover soils. CONCLUSIONS: Oxidation activity and community structure of methanotrophs varied with depth and age of landfill cover soils. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings provide new fundamental information regarding the activity and diversity of methanotrophs in landfill cover soils of different age that may aid predicting and modelling CH4 flux from landfills.


Assuntos
Metano/metabolismo , Proteobactérias/classificação , Proteobactérias/metabolismo , Microbiologia do Solo , Instalações de Eliminação de Resíduos , Metano/análise , Methylococcaceae/isolamento & purificação , Oxirredução , Proteobactérias/isolamento & purificação , Solo/química
9.
Pathol Res Pract ; 208(6): 344-9, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22537506

RESUMO

This study investigated whether urinary trypsin inhibitor (UTI) inhibits neointimal formation by reducing inflammatory response after stent injury. Twenty minipigs having undergone oversized bare material stent implantation in the left anterior descending artery were randomly subdivided into two groups: a UTI group (n=10) and a control group (n=10). Two systemic markers of inflammation (serum macrophage chemoattractant protein-1 and interleukin-6 levels measured by ELISA) were increased after stent implantation, and two days after stem implantation, their levels were positively correlated with the maximal percentage of area stenosis on day 28 (r(2)=0.889 and 0.743, respectively). This effect was abolished by UTI administration. Twenty-eight days after implantation, morphometric analysis of the stented arteries revealed significantly reduced luminal stenosis (38±6% vs. 64±12%, P<0.05), a neointimal area (3.22±0.57 mm(2) vs. 5.21±1.04 mm(2), P<0.05), neointimal thickness (0.31±0.13 mm vs. 0.46±0.16 mm, P<0.05), and an inflammatory score of 1.02±0.05 vs. 1.30±0.08 in UTI-treated animals as compared with controls. Twenty-eight days after stenting, arterial nuclear factor-κB expression was 36.93±7.16% in all of the cells in controls and 23.32±4.54% in UTI-treated minipigs. UTI could reduce neointimal formation after stenting by inhibiting the local and the systemic inflammatory response. Percutaneous coronary intervention could benefit from precocious anti-inflammatory treatment.


Assuntos
Reestenose Coronária/tratamento farmacológico , Estenose Coronária/patologia , Glicoproteínas/farmacologia , Inflamação/tratamento farmacológico , Stents/efeitos adversos , Inibidores da Tripsina/farmacologia , Animais , Constrição Patológica/tratamento farmacológico , Constrição Patológica/patologia , Reestenose Coronária/patologia , Vasos Coronários/patologia , Vasos Coronários/cirurgia , Modelos Animais de Doenças , Inflamação/patologia , Neointima/induzido quimicamente , Suínos , Porco Miniatura
10.
Prostaglandins Leukot Essent Fatty Acids ; 67(5): 293-302, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12445488

RESUMO

Fatty acids such as palmitate have been observed to induce apoptosis in cardiomyocytes but the mechanism of this cytotoxicity is unresolved. The present study sought to determine whether an aspect of fatty acid metabolism is responsible for palmitate-induced apoptosis in cardiomyocytes. As palmitate metabolism increases acetyl CoA production via increased beta oxidation within the mitochondria, we hypothesized that increased acetyl CoA entering the cholesterol biosynthesis pathway might produce intermediates or end products that would be toxic to the cell. To test this hypothesis, cardiomyocytes from embryonic chick cardiomyocytes were treated with the 3-hydroxy-3-methylgutaryl CoA (HMG-CoA) reductase inhibitor lovastatin that inhibits the cholesterol biosynthesis pathway downstream of the acetyl CoA trimerization into HMG-CoA. Lovastatin did not inhibit palmitate-induced apoptosis. Rather, lovastatin induced significant apoptosis itself and when combined with palmitate, the level of apoptosis was equal to the sum of palmitate alone and lovastatin alone. This observation suggests that palmitate and lovastatin are inducing apoptosis by two independent mechanisms. A role for mitochondrial metabolism via carnitine palmitoyl transferase (CPT) in palmitate-induced apoptosis was suggested since capric acid, a fatty acid that is metabolized within the mitochondria but does not utilize CPT-1, did not induce apoptosis. Palmitate-induced apoptosis was further related to the metabolism of saturated fatty acids as the unsaturated fatty acid oleic acid did not induce apoptosis. These data suggest that a unique feature about palmitate metabolism independent of its role in cholesterol biosynthesis is responsible for palmitate-induced apoptosis and the effects of palmitate are additive to those of lovastatin to induce cardiac apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Lovastatina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ácido Palmítico/farmacologia , Laranja de Acridina , Animais , Anexina A5/metabolismo , Embrião de Galinha , DNA/análise , Ácidos Decanoicos/farmacologia , Interações Medicamentosas , Citometria de Fluxo , Marcação In Situ das Extremidades Cortadas , Miócitos Cardíacos/metabolismo , Ácido Oleico/farmacologia , Ácido Palmítico/toxicidade , Ligação Proteica/efeitos dos fármacos
11.
Bioorg Med Chem Lett ; 11(21): 2855-7, 2001 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-11597415

RESUMO

Two series of compounds, 2 and 3, were synthesized and their binding affinities were evaluated for the human recombinant muscarinic M(1) receptor subtype expressed in CHO cells. Comparing their binding affinities for the NMS binding sites and the Oxo-M binding sites, they were assumed as agonists. In particular, compound 2e was a good ligand for the agonist binding sites with an IC(50) of 23 nM, which represents over 1585 times stronger binding than for the antagonist binding sites.


Assuntos
Compostos Aza/síntese química , Compostos Aza/metabolismo , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/metabolismo , Receptores Muscarínicos/metabolismo , Animais , Células CHO , Cricetinae , Ligantes , Receptor Muscarínico M1
12.
Life Sci ; 68(13): 1567-73, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11253173

RESUMO

Acori graminei Rhizoma (AGR) is shown to exhibit a number of pharmacological actions including sedation and anticonvulsive action. To further characterize its actions in the CNS, the present study evaluated the effects of essential oils (EO) from AGR on the excitotoxic neuronal cell death induced in primary rat cortical cell cultures. EO inhibited the glutamate-induced excitotoxicity in a concentration-dependent manner, with the IC50 of 0.241 mg/ml. EO exerted more potent neuroprotection against the toxicity induced by NMDA (IC50 = 0.139 mg/ml). In contrast, the AMPA-induced toxicity was not inhibited by EO. Receptor-ligand binding studies were performed to investigate the neuroprotective action mechanism. EO dramatically inhibited the specific bindings of a use-dependent NMDA receptorion channel blocker [3H]MK-801, indicating an NMDA receptor antagonist-like action. However, the bindings of [3H]MDL 105,519, a ligand selective for the glycine binding site of NMDA receptor, were not considerably inhibited. These results demonstrated that EO extracted from AGR exhibited neuroprotective effects on cultured cortical neurons through the blockade of NMDA receptor activity, and that the glycine binding site appeared not to be the major site of action.


Assuntos
Córtex Cerebral/efeitos dos fármacos , N-Metilaspartato/toxicidade , Fármacos Neuroprotetores/farmacologia , Óleos de Plantas/farmacologia , Plantas Medicinais/química , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Maleato de Dizocilpina/metabolismo , Relação Dose-Resposta a Droga , Feminino , Indóis/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Óleos Voláteis/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Membranas Sinápticas/efeitos dos fármacos , Membranas Sinápticas/metabolismo
13.
Am J Physiol Heart Circ Physiol ; 279(6): H3089-100, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11087267

RESUMO

We examined the hypothesis that sodium nitroprusside (SNP) produces cell death in cardiomyocytes through generation of H(2)O(2). Embryonic chick cardiomyocytes in culture were treated with SNP, and cell viability was assessed by trypan blue, MTT assay, and fluorescent activated cell sorting (FACS) analysis. SNP for 24 h induced a significant (P < 0.001) dose-dependent loss of cell viability. On MTT assay, the half-maximal effective concentration was 0.53 mM (confidence interval 0.45-0.59 mM). SNP-treated cardiomyocytes displayed characteristic microscopic features of apoptosis: reduced cell size, nuclear disintegration, and membrane bleb formation. FACS analysis demonstrated SNP-induced apoptosis as well as cell changes consistent with necrosis. The proportion of cells with nuclear changes of apoptosis, identified by propidium iodide (PI) staining of permeabilized cells, increased significantly (P < 0.05) after 0.5 mM SNP for 24 h. The proportion of apoptotic cells, characterized by dual staining of intact cardiomyocytes with fluorescein diacetate and PI, was significantly (P < 0.05) increased after treatment with 0.5 mM SNP for 24 h. SNP metabolism and NO production was suggested by the significant (P < 0.05) increase in nitrite generation in the media with 0.5 mM SNP compared with control. SNP-mediated H(2)O(2) production was implicated in the mechanism of SNP-induced cell death. First, SNP produced a significant (P < 0.05) increase in H(2)O(2) detected in the media after 6 or 24 h of SNP treatment. Second, catalase completely blocked the reduction of cell viability induced by 0.1 mM SNP and significantly (P < 0.05) blunted the effect of 0.5 mM SNP. In contrast, the iron chelator deferoxamine did not alter SNP-induced loss of cell viability. FACS analysis showed that the combination of low concentrations of H(2)O(2) (10(-8) M) that did not alter cell viability augmented SNP-induced apoptosis. In contrast, the amount of necrotic cell death was unchanged by the combination of H(2)O(2) and SNP. H(2)O(2) plus SNP produced a dramatic alteration in cell structure with greater membrane bleb formation, shrunken cells, and more intense cytosolic acridine orange staining and nuclear fragmentation than either agent alone. These data indicate the vulnerability of cardiomyocytes to SNP and suggest the involvement of H(2)O(2) in the pathogenesis of SNP-induced cardiomyocyte cell death. Establishing apoptosis as a component of the type of cell death induced by SNP permitted the recognition that SNP-induced apoptosis was increased by chronic treatment with low (subtoxic) concentrations of H(2)O(2).


Assuntos
Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Fibras Musculares Esqueléticas/citologia , Miocárdio/citologia , Nitroprussiato/farmacologia , Oxidantes/toxicidade , Vasodilatadores/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga , Interações Medicamentosas , Citometria de Fluxo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Óxido Nítrico/metabolismo
14.
J Ethnopharmacol ; 73(1-2): 31-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11025136

RESUMO

Acori graminei rhizoma (AGR) are reported to exhibit a number of pharmacological actions in the central nervous system. The effects of the methanol extract of AGR on excitotoxic neuronal death were evaluated in the present study using cultured rat cortical neurons. Based on the phase-contrast microscopic examinations of cultures and lactate dehydrogenase activities measured in the culture media, the glutamate-induced excitotoxicity was significantly inhibited by the extract. The inhibitory action of the extract was more potent and selective for the N-methyl-D-aspartate (NMDA) receptor-mediated toxicity. The AGR extract competed with [3H]MDL 105,519 for the specific binding to the glycine site of the NMDA receptor with the IC(50) value of 164.7 microg/ml. Modulation of the NMDA receptor activity by the extract was determined using [3H]MK-801 binding studies. The reduction of the binding in the presence of the extract indicated the receptor inactivation by AGR. These results demonstrated that the methanol extract of AGR exhibited protective action against excitotoxic neuronal death, and that the neuroprotective action was primarily due to the blockade of NMDA receptor function by the interaction with the glycine binding site of the receptor.


Assuntos
Neurônios/efeitos dos fármacos , Neurotoxinas/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Morte Celular , Células Cultivadas , Córtex Cerebral , Maleato de Dizocilpina/metabolismo , L-Lactato Desidrogenase/metabolismo , Neurotoxinas/toxicidade , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/metabolismo , Membranas Sinápticas/efeitos dos fármacos , Membranas Sinápticas/metabolismo
15.
Peptides ; 21(8): 1237-47, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11035211

RESUMO

The ability of angiotensin II (ang II) to produce apoptosis is controversial. Cardiomyocytes, isolated from 7-day embryonic chick hearts and maintained in culture for 72 h, were treated with ang II. There was no evidence of ang II-induced apoptosis consistently demonstrated by six different techniques: electrophoretic separation of fragmented DNA, staining with TUNEL, enzyme-linked immunosorbent assay specific for fragmented DNA, dual staining of cells with fluorescein diacetate and propidium iodide with analysis by flow cytometry, staining of nuclei with propidium iodide and cell microscopy. In contrast, apoptosis was readily induced by camptothecin or staurosporine or serum deprivation. The absence of ang II-induced cell death was also demonstrated in neonatal mouse cardiomyocytes in culture. We further sought to answer the question whether ang II Type 1 receptor blockade by antagonizing the potential beneficial effects mediated through this receptor and producing more ang II binding to the ang II Type 2 receptors, would lead to cardiac apoptosis. There was no evidence of ang II-induced apoptosis in the presence of the ang II Type 1 receptor antagonist losartan in embryonic chick cardiomyocytes. Rather ang II prevented serum deprivation-induced apoptosis. In summary, in these cardiomyocytes ang II does not induce but rather prevents apoptosis.


Assuntos
Angiotensina II/fisiologia , Apoptose , Miocárdio/citologia , Angiotensina II/metabolismo , Animais , Animais Recém-Nascidos , Camptotecina/farmacologia , Núcleo Celular/metabolismo , Separação Celular , Células Cultivadas , Embrião de Galinha , Meios de Cultura Livres de Soro , Fragmentação do DNA , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Coração/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Camundongos , Necrose , Propídio/farmacologia , Estaurosporina/farmacologia , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo
16.
Arch Pharm Res ; 23(3): 246-51, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10896057

RESUMO

In most tissues, apoptosis plays a pivotal role in normal development and for regulating cell number, thus inappropriate apoptosis underlies a variety of diseases. Caspase-3 is one of a family of caspases that are mainly involved in the apoptotic signal transduction pathway, where caspase-3 acts as an effect molecule to proteolytically cleave intracellular substrates that are necessary for maintaining cell survival. Recent evidences show that apoptotic cell death can be blocked by inhibiting caspase-3, suggesting its inhibitors have potential to be therapeutic drugs for the diseases related with inappropriate apoptosis. We have established a screening system to search caspase-3 inhibitors from chemical libraries stocked in our institute. The enzyme assay is configured entirely in 96-well format, which is easily adapted for high throughput screening. Before performing mass screening, 80 in-house compounds were screened as a preliminary experiment, and we found that morin hydrate inhibited caspase-3 by 66.4% at the final concentration of 20 microM.


Assuntos
Inibidores de Caspase , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3 , Ativação Enzimática , Escherichia coli , Humanos
17.
Arch Pharm (Weinheim) ; 333(5): 113-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10863794

RESUMO

The synthesis and biological testing of 5-(4-alkoxy-[1,2,5]thiadiazol-3-yl)-3-methyl-1,2,3,4-tetrahydro pyrimidine oxalate salts 8 as muscarinic receptor agonists are described. The key intermediate 4 was obtained by modified Strecker reaction and cyclization of starting material 1. Subsequent alkoxy substitution, quaternization, and reduction afforded 7. For the sake of purity and stability of the final products 8, the 3-methyl-1,2,3,4-tetrahydropyrimidines were obtained as oxalic acid salts. All final compounds were examined in vitro for their binding affinities to the cloned human muscarinic receptor by the [3H]-NMS binding assay.


Assuntos
Agonistas Muscarínicos/síntese química , Pirimidinas/síntese química , Tiadiazóis/síntese química , Doença de Alzheimer/tratamento farmacológico , Ligação Competitiva , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Agonistas Muscarínicos/farmacologia , N-Metilescopolamina/metabolismo , Ligação Proteica , Pirimidinas/farmacologia , Receptor Muscarínico M1 , Receptores Muscarínicos/metabolismo , Proteínas Recombinantes/metabolismo , Tiadiazóis/farmacologia
18.
Brain Res Mol Brain Res ; 77(2): 176-84, 2000 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10837913

RESUMO

Hydrogen peroxide, at concentrations comparable to those observed under some pathological conditions, produced a concentration-dependent inhibition of state 3 (ADP-stimulated) and uncoupled mitochondrial respiratory activity. The ADP:O ratio was also substantially reduced. In contrast, the organic peroxide, t-butylhydroperoxide at the same concentrations produced no significant changes in respiratory activity. Intramitochondrial glutathione was oxidised to a similar extent in the presence of hydrogen peroxide or t-butylhydroperoxide. Thus, changes in this endogenous antioxidant apparently did not underlie the different responses to these peroxides. The effects of hydrogen peroxide were not altered by deferoxamine indicating that the extramitochondrial generation of hydroxyl radicals was not likely to be involved. However, modifications arising from the generation of hydroxyl radicals within the mitochondria remain a likely contributor to the observed deleterious effects on respiratory function. The inhibitory effects of hydrogen peroxide were greatest when pyruvate plus malate were present as respiratory substrates. Lesser inhibition was seen with glutamate plus malate and no significant inhibitory effects were detected in the presence of succinate. The findings suggest that mitochondrial components involved in pyruvate oxidation were particularly sensitive to the hydrogen peroxide treatment. However, no significant change was seen in activity of either the pyruvate dehydrogenase complex or NADH-ubiquinone oxidoreductase (complex I) when measured directly following treatment of the mitochondria with hydrogen peroxide.


Assuntos
Encéfalo/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Mitocôndrias/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Desferroxamina/farmacologia , Relação Dose-Resposta a Droga , Complexo I de Transporte de Elétrons , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Dissulfeto de Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Cinética , Malatos/metabolismo , Malatos/farmacologia , Masculino , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , NADH Desidrogenase/metabolismo , NADH NADPH Oxirredutases/metabolismo , Oxigênio/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacologia , Ratos , Ratos Endogâmicos , Ácido Succínico/metabolismo , Ácido Succínico/farmacologia , terc-Butil Hidroperóxido/metabolismo , terc-Butil Hidroperóxido/farmacologia
19.
Biochim Biophys Acta ; 1485(1): 45-55, 2000 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-10802248

RESUMO

Palmitate, a C16 fatty acid found in high concentrations in the blood in acute myocardial infarction, induces apoptotic cell death. To more completely define the nature and mechanism underlying palmitate-induced cell death, cardiomyocytes were cultured from embryonic chick heart and were treated with palmitate. Concentration-dependent loss of cell viability was established by loss of the ability of palmitate-treated cells to exclude propidium iodide (PI), metabolize 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and retain fluorescein diacetate (FDA). Dual staining with PI and FDA and subsequent analysis by FACS established that palmitate-induced cell death was predominantly necrosis whereas apoptosis occurred in 13% of all dead cells. The low proportion of palmitate-induced apoptosis was confirmed by evaluation of the DNA content or PI fluorescent staining of the DNA of permeabilized cardiomyocytes. A critical role for mitochondria in the pathogenesis of palmitate-induced cell death was demonstrated, for the first time, based on palmitate-induced reduction of mitochondrial activity as assessed by the mitochondrial-selective dye chloromethyl-X-Rosamine and the presence of a greater amount of the mitochondrial marker cytochrome C in the cytosol of palmitate-treated cardiomyocytes than in control cells. Further, cyclosporin that inhibits the development of mitochondrial transition pores blocked palmitate-induced alteration in mitochondrial function and palmitate-induced cell death. We further demonstrated the selectivity of cyclosporin A for the prevention of apoptotic cell death in the heart as there was no alteration in necrotic cell death produced by palmitate with cyclosporin pretreatment. Our data demonstrate the nature of palmitate-induced cell death in cardiomyocytes (both apoptotic and necrotic), propose a mitochondrial basis for its pathogenesis and show that cyclosporin A prevents palmitate-induced apoptotic cardiomyocyte cell death.


Assuntos
Apoptose/efeitos dos fármacos , Ciclosporina/farmacologia , Coração/efeitos dos fármacos , Ácido Palmítico/farmacologia , Animais , Núcleo Celular/química , Sobrevivência Celular , Células Cultivadas , Embrião de Galinha , Grupo dos Citocromos c/metabolismo , Citoplasma/metabolismo , DNA/análise , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/ultraestrutura , Potenciais da Membrana , Mitocôndrias/efeitos dos fármacos , Miocárdio/citologia , Miocárdio/patologia , Necrose , Ácido Palmítico/antagonistas & inibidores
20.
Mol Cells ; 10(1): 13-7, 2000 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-10774741

RESUMO

The insect diuretic hormone (DH) binds to their receptor in malpighian tubules, and stimulates water secretion and cAMP synthesis. Complementary DNA encoding a diuretic hormone receptor was cloned from the malpighian tubules of Bombyx mori. The cloned cDNA encodes a protein consisting of 391 amino acid residues with the seven transmembrane domains. The receptor protein is homologous with that of other insects, and is structurally related to G-protein coupled receptors such as corticotropin relating factor (CRF), secretin, and vasoactive intestinal peptide.


Assuntos
Bombyx/genética , DNA Complementar/genética , Hormônios de Inseto/metabolismo , Proteínas de Insetos , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , Túbulos de Malpighi/metabolismo , Dados de Sequência Molecular , Receptores de Superfície Celular/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
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