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51.
Alcohol increases c-myc mRNA and protein in skeletal and cardiac muscle   总被引:1,自引:0,他引:1  
The pathogenic mechanisms responsible for alcohol-induced muscle disease are unknown, although it is possible that increased proto-oncogene expression may be the causative process. Therefore, we investigated the responses of skeletal muscle c-myc protein and mRNA to a standard acute ethanol dosage regimen (75 mmol/kg/body weight [BW]) for 2.5 to 24 hours. Comparative studies were made on the heart. Acute ethanol administration in vivo led to an increase in c-myc proto-oncogene mRNA in rat skeletal and cardiac muscle. The changes in c-myc mRNA were mirrored by increases in the c-myc protein as demonstrated by immunohistochemistry. The changes in the c-myc protein were localized to the myonuclei, with no corresponding changes seen in the interstitial cell nuclei. This is the first report of altered proto-oncogene expression in muscle in response to ethanol. Increased c-myc mRNA and protein may reflect adaptive changes, a stress response, or another uncharacterized cellular adaptation.  相似文献   
52.
Urinary bile acids from 20 patients treated with chenodeoxycholate, 18 treated with ursodeoxycholate, 15 treated with rifampicin and 8 patients with advanced cirrhosis were analyzed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. Occurrence rates and amounts of three so-called unusual trihydroxy bile acids, hyocholate, ursocholate and omega-muricholate, were increased in patients treated with chenodeoxycholate, ursodeoxycholate or rifampicin and decreased in cirrhotic patients as compared with those in untreated healthy adults. These data suggest that chenodeoxycholate and ursodeoxycholate are hydroxylated to produce unusual trihydroxy bile acids in bile acid-loaded humans and that this metabolism may be related to the induction of hepatic microsomal enzymes by rifampicin. In contrast, the hydroxylation of chenodeoxycholate and ursodeoxycholate may be impaired by severe hepatic damage. Because the urine is a secretory pathway for internal bile acids, the occurrence of unusual trihydroxy bile acids in the urine may be used as an indicator of hepatic ability to metabolize "hydrophobic" dihydroxy bile acids to their secretory forms.  相似文献   
53.
Background/Purpose. An aggressive approach is required to resect advanced carcinoma of the gallbladder. Therefore, an extended surgical procedure often brings about a poor surgical outcome. To test whether an aggressive surgical treatment can improve the survival rate for primary advanced carcinoma of the gallbladder, 59 patients with stage IV primary gallbladder carcinoma were studied. Methods. Patients were divided into three treatment groups for the survival analysis: group A (resectional surgery, n = 29), group B (low-dose cis-diamminedichloroplatinum-II and 5-fluorouracil therapy, n = 10), and group C (exploratory laparotomy, other treatment modalities, or no treatment, n = 20). Results. The prognosis of group A patients was significantly better than that of group B (P = 0.018) or group C (P = 0.0009). Furthermore, group A patients were divided into subgroups. The prognosis of patients resected with no distant metastasis (group A1) was significantly better than that of patients resected with distant metastases of the distant lymph nodes and the liver (group A2) (P = 0.0004). Also, there was no significant difference in the survival rate between the patients resected with distant metastasis (group A2) and chemotherapy cases (group B). Conclusions. These results indicated that radical surgery should be performed for patients with no distant metastasis, and that chemotherapy might be a useful alternative treatment for patients with distant metastasis in advanced carcinoma of the gallbladder.  相似文献   
54.
STUDY OBJECTIVE: To characterize clinical, radiographic, and CT findings of chronic necrotizing pulmonary aspergillosis (CNPA) in patients with pneumoconiosis. METHODS: We studied 10 patients with pneumoconiosis who were seen at Asahi Rosai Hospital and received a clinical diagnosis of CNPA during a 15-year period, and detailed the long-term clinical and radiologic courses of four cases. RESULTS: All patients were men, ranging in age from 48 to 77 years (mean, 60.1 years). Their occupational histories included pottery making (n = 9) and coal mining (n = 1). Chest radiographic findings by the International Labor Organization profusion grading system were greater than category 2. All patients were symptomatic, with a productive cough, hemoptysis, and dyspnea. Serum findings were positive for the Aspergillus antibody in seven patients. The radiologic findings consisted of parenchymal infiltrates and cavities mostly containing mycetoma, which generally involved the upper lobes. The disease progressed slowly; in one patient, broad destruction of the lung was observed after > 10 years without antifungal administration. Most of the patients experienced clinical and radiologic improvement after receiving antifungal therapy, by oral, inhaled, or intracavitary administration. CONCLUSIONS: Chronic persistent or progressive upper-lobe infiltrates and cavities in patients with pneumoconiosis should raise the possibility of CNPA. Early diagnosis and initiation of effective therapy are recommended to achieve a better outcome.  相似文献   
55.
We have established an ELISA for detecting thrombin cleavage of the FVIII light chain at Arg1689. The method used a coating alloantibody which recognized amino acid residues 2248–2312 in the C2 domain, together with a second monoclonal antibody, NMC-VIII/10, which recognized residues 1675–1684 in the amino-terminal region of the light chain. FVIII antigen (FVIII:Ag) was measured after treatment of plasma with various concentrations of thrombin. The FVIII:Ag of normal plasma was reduced in a dose-dependent manner by the thrombin, falling to 28% in the presence of 100 U/ml enzyme. The concentration of thrombin that achieved 50% reduction (IC50) was approximately 1·0 U/ml. The plasma of four haemophilia A positive (A+) and two haemophilia A reduced (AR) patients were analysed. The IC50 of all patients was more than 1·0 U/ml, indicating that thrombin cleavage of the FVIII light chain was defective. One haemophilia A+ plasma did not respond to thrombin in this ELISA system. The patient (TI) was a haemophiliac with FVIII coagulant activity of 0·04 U/ml and FVIII:Ag of 1·78 U/ml. In addition, immunoblotting of the purified FVIII from TI showed that thrombin cleavage of the 80 kilodalton (kD) light chain was impaired. The patient's DNA was amplified using the polymerase chain reaction with a set of synthetic oligonucleotide primers spanning amino acid residues 1646–1714. Sequence analysis of the amplified DNA fragments revealed a cytosine to thymine transition, converting an arginine 1689 to cysteine. This abnormal FVIII was designated as FVIII Hiroshima. Our ELISA system is a simple and useful method of evaluating the proteolytic cleavage by thrombin at Arg1689.  相似文献   
56.
Cytotrophoblasts differentiate in two directions during early placentation: syncytiotrophoblasts (STBs) and extravillous trophoblasts (EVTs). STBs face maternal immune cells in placentas, and EVTs, which invade the decidua and uterine myometrium, face the cells in the uterus. This situation, in which trophoblasts come into contact with maternal immune cells, is known as the maternal-fetal interface. Despite fetuses and fetus-derived trophoblast cells being of the semi-allogeneic conceptus, fetuses and placentas are not rejected by the maternal immune system because of maternal-fetal tolerance. The acquired tolerance develops during normal placentation, resulting in normal fetal development in humans. In this review, we introduce placental development from the viewpoint of molecular biology. In addition, we discuss how the disruption of placental development could lead to complications in pregnancy, such as hypertensive disorder of pregnancy, fetal growth restriction, or miscarriage.  相似文献   
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