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991.
OBJECTIVE: The aim of this study was to find whether there is a relationship between the changes in the amounts of hepatitis C virus (HCV) at the start of interferon treatment and the long term response to therapy. METHODS: In 20 patients with HCV genotype 1b each given 880 MU of interferon-alpha, the changes in serum HCV RNA during the first 2 wk of therapy were monitored by real-time quantitative polymerase chain reaction (PCR). RESULTS: Real-time quantitative PCR detected HCV RNA at 10(1)-10(8) copies/ml. Serum HCV RNA decreased rapidly between 8 and 24 h after the first administration (first phase) and more slowly thereafter (second phase), with median exponential decays of 2.14 and 0.11 log10/day, respectively. Four patients had sustained virological responses, nine patients had transient responses, and seven patients had no responses. The differences in the rate of first-phase viral decline among the three groups were not significant (p = 0.34), but the differences in the rate of second-phase viral decline were significant (p = 0.0004); the median viral decline (interquartile range) in the second phase was 0.48 (0.42-0.50) log10/day in patients with sustained responses, 0.16 (0.10-0.19) log10/day in patients with transient responses, and 0.026 (0.017-0.040) log10/day in patients with no responses. CONCLUSIONS: Changes in serum levels of HCV genotype 1b in the first 2 wk of interferon-alpha treatment, monitored by real-time quantitative PCR, can be used for prediction of the long term therapeutic response.  相似文献   
992.
Gene array testing defined the intrinsic biological subtypes including"luminal A", "luminal B", "HER2-enriched" and "basal" within breast cancer. These subtypes may be approximated using clinicopathological immunochemistry rather than gene expression array criteria. These subtypes have different epidemiological risk factors, different natural histories, and different response to systemic and local therapies. Systemic therapy recommendations follow the subtype classification. "Estrogen receptor", "progesterone receptor", "human epidermal growth factor receptor 2" and "Ki67" are the most important biological markers to classify the subtypes and predict the prognosis and the response to the therapy. The new targeting therapy will require new biomarkers.  相似文献   
993.
We present the case of an elderly woman with myasthenia gravis who had pleural dissemination of thymoma reduced by treatments with a moderate dose of corticosteroids and a conventional dose of tacrolimus. A maintenance dose of prednisolone for myasthenia gravis could not shrink the size of the disseminated thymoma, but prednisolone (>30 mg daily) succeeded in reducing the size of the tumor. Moreover, a combination with tacrolimus enabled the daily dose of prednisolone to be tapered off without recurrence of myasthenia gravis, and the disseminated thymoma almost disappeared. A moderate or higher dosage of corticosteroids with tacrolimus may, in some cases, be an effective procedure for pleural dissemination of thymoma. Treatment should be undertaken on a trial basis for patients not indicated for surgery, radiotherapy, or chemotherapy.  相似文献   
994.
The present study was performed to determine whether melatonin protects mouse liver against severe damage induced by acetaminophen (APAP) administration and where melatonin primarily functions in the metabolic pathway of APAP to protect mouse liver against APAP-induced injury. Treatment of mice with melatonin (50 or 100 mg/kg, p.o.) 8 or 4 hr before APAP administration (750 mg/kg, p.o.) suppressed the increase in plasma alanine aminotransferase and aspartate aminotransferase activities in a dose- and a time-dependent manner. Melatonin treatment (100 mg/kg, p.o.) 4 hr before APAP administration remarkably inhibited centrilobular hepatic necrosis with inflammatory cell infiltration and increases in hepatic lipid peroxidation and myeloperoxidase activity, an index of tissue neutrophil infiltration, as well as release of nitric oxide and interleukin-6 into blood circulation at 9 hr after APAP administration. However, melatonin neither affected hepatic reduced glutathione (GSH) content nor spared hepatic GSH consumption by APAP treatment. Moreover, pretreatment with melatonin 4 hr before APAP administration did not influence the induction of hepatic heat shock protein 70 (HSP70) by APAP and melatonin alone did not induce HSP70 in mouse liver. These results indicate that exogenously administered melatonin exhibits a potent hepatoprotective effect against APAP-induced hepatic damage probably downstream of the activity of cytochrome P450 2E1, which works upstream of GSH conjugation in the pathway of APAP metabolism, via its anti-nitrosative and anti-inflammatory activities in addition to its antioxidant activity.  相似文献   
995.
Since many of antiarrhythmic drugs can act on variable ion channels of cardiac myocytes, these compounds may also play a role in the activity of similar ion channels expressed on the vascular smooth muscle cells. In contrast, some of these ion channels expressed on vasculature have different subtypes of the channels, indicating that antiarrhythmic drugs may differentially affect ion channels on cardiac myocytes and vascular smooth muscle cells. Therefore, it is crucial to note the effects of antiarrhythmic drugs on the regulation of vascular function. Previous studies using isolated blood vessels as well as cultured vascular smooth muscle cells indicate that antiarrhythmic drugs have some modulator effects on K+ channels expressed on the vascular smooth muscle cells. In addition, this modulation may be modified and dependent on the sort of stimuli, including those of pharmacological and pathophysiological. The K+ channel is one of the most important ion channels modulating vascular function to preserve the organ blood flow including that of the brain as well as the heart, and that several available K+ channel openers are expected to treat cardiovascular disorders, including hypertension, ischemic heart disease. Therefore, these results may provide us a hint to understand the advantage and/or disadvantage of these compounds on the vascular function.  相似文献   
996.
A 42-year-old woman with hypoglycemic symptoms that occurred several hours after a meal visited our hospital. The hypoglycemic symptoms appeared when she was 37 years old, and her plasma glucose level had been assessed as less than 60 mg/dL when she experienced the symptoms. One year before, she had been diagnosed with reactive hypoglycemia by 75 g-oral glucose tolerance test (OGTT), which showed a normal glucose tolerance (NGT) pattern, and had begun taking an alpha-glucosidase inhibitor and nutritional treatment. A 75 g-OGTT on admission showed hypoglycemia at 240 min after glucose loading, excessive insulin secretion and an impaired glucose tolerance (IGT) pattern. A euglycemic-hyperinsulinemic clamp study demonstrated decreased insulin sensitivity. Therefore, we suspected that she had reactive hypoglycemia associated with insulin resistance and treated her with 15 mg/day pioglitazone. Her hypoglycemic symptoms completely disappeared after treatment with pioglitazone; insulin sensitivity in a euglycemic-hyperinsulinemic clamp study improved. Another 75 g-OGTT revealed that the excessive insulin secretion and hypoglycemia at 240 min after glucose loading had disappeared, and glucose tolerance was normalized from an IGT pattern to an NGT pattern. Thus, we believe that pioglitazone is effective for reactive hypoglycemia and aggravated glycemic metabolism associated with insulin resistance.  相似文献   
997.
Natural killer T (NKT) cells share features of both classical T cells and NK cells. NKT are heterogenous populations, and recognize glycolipids associated with CD1d molecule. We investigated Th1/Th2 cytokine production as well as frequency and phenotype of circulating NKT cells in 14 healthy subjects and in patients during therapy with type C chronic hepatitis (CH; 14 cases) and hepatocellular carcinoma (HCC; 13 cases). Peripheral blood mononuclear cells (PBMC) were obtained before and 2 weeks later interferon (IFN)/ribavirin and radiofrequency ablation therapy for CH and HCC, respectively. PBMC were cultured for 10 days with alpha-galactosylceramide (alpha-GalCer) and interleukin-2 (IL-2). Frequencies and IFN-gamma/IL-4 production of NKT cells were analyzed using flow cytometry. Intrahepatic lymphocytes were analyzed in seven CH patients with liver biopsy specimen. Prevalence of circulating Valpha24+CD3+ T cells was 0.9+/-0.9% of PBMC for controls and increased to 8.5+/-8.9% (p<0.001) in response to alpha-GalCel. Similar frequency and expansion were noted in CH. The frequency increased during therapy. The prevalence in HCC tended to be high compared to controls and response to alpha-GalCel was well. Although frequency of Valpha24+Vbeta11+CD3+ T cells was low in all groups, the distribution pattern was similar to Valpha24+Vbeta11-CD3+ T cells. Prevalence of CD56+CD3+ T cells was low independent of therapy in CH (2-3%) compared to 5.0+/-4.0% of controls, although response to alpha-GalCel was not impaired. IFN-gamma production of Valpha24+CD3+ T cells did not differ among groups, but became greater after treatment in contrast to lowered IL-4 production. Frequencies of NKT populations were higher in liver than in peripheral blood. Our study suggests that CD1d-reactive T cells have distinct distribution in different populations and therapy for patients alters cytokine response of NKT cells.  相似文献   
998.
The aim of the present study was to investigate the prognostic significance of time-delay to peak creatine kinase (CK) after successful direct percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI). Our 240 consecutive first AMI attack subjects admitted within 5 hours from onset were successfully reperfused by direct PCI therapy. Subjects were divided into two groups according to the upper quartile value of peak-CK time from onset, the early peak-CK group (peak-CK time < or = 16 hours from onset, n = 180) and the late peak-CK group (peak-CK time > 16 hours, n = 60). (I) The early ST-segment resolution rate was lower in the late peak-CK group compared with the early peak-CK group (P < 0.05), and there were significantly fewer patients with preinfarction angina pectoris in the late peak-CK group than in the early peak-CK group (P < 0.01). (II) LVEF in the chronic stage was significantly lower in the late peak-CK group than in the early peak-CK group (49 +/- 13% versus 57 +/- 13%, P < 0.001). (III) There were significantly more patients with major complications in the late peak-CK group than in the early peak-CK group (required CABG: 10% versus 3%, P < 0.05; cardiac death: 18% versus 3%, P = 0.0001). (IV) Multivariate analysis identified late peak-CK as an independent predictor of cardiac death (Odds ratio 7.91, 95% C.I. 1.40-44.11, P < 0.05). In patients with AMI, the time-delay to peak-CK after successful direct PCI may be closely related to left-ventricular systolic dysfunction and poor patient outcome, including mortality.  相似文献   
999.
1000.
Eight distinct and potentially causative mutations were identified in eight unrelated Japanese patients with protein S (PS) deficiency, by direct DNA sequencing of the protein Salpha (PSalpha) gene-specific polymerase chain reaction products of all 15 exons and exon/intron boundaries. There were five missense mutations, including two novel mutations (Cys80Tyr and Arg314His), and three showed a major impact on the expected gene products: novel mutations of a 5-bp deletion (delCTCTG887:Cys206Stop) and a nonsense mutation (Glu208Stop), as well as a previously reported splice site (exon 10 +5 A-->G) mutation. One of the patients showed compound heterozygosity for delCTCTG887 and 732A-->G. Investigation for the cosegregation state of these two mutations with PS deficiency in the patient's family suggested that the delCTCTG887 mutation was responsible for the abnormal phenotype and that the 732A-->G (Lys155Glu) mutation did not appear to play a key role. However, we also identified the same 732A-->G (Lys155Glu) mutation in an unrelated patient with apparent PS deficiency with severe pulmonary embolism, and found that this mutation seemed to cosegregate with a PS-deficient state in her family members. These data implied that unknown factor(s) other than the 732A-->G mutation itself might influence phenotypic expression of PS status in different individuals.  相似文献   
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