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1.
J C Ho M Chan-Yeung S P Ho J C Mak M S Ip G C Ooi M P Wong K W Tsang W K Lam 《The European respiratory journal》2007,29(2):273-278
The present study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with nonsmall cell lung carcinoma (NSCLC). A comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects was conducted. The antioxidants catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured using chemical kinetic reactions under spectrophotometry. In total, 189 cases of mostly advanced-stage IIIB or stage IV NSCLC and 202 healthy controls were studied. In subjects with lung cancer, there was similar catalase activity, lower SOD activity (median (interquartile range) 13.4 (9.0-27.2) versus 48.7 (27.0-64.3) U x (ghaemoglobulin(Hb)(-1)), and higher GPx activity (175.2 (126.6-288.3) versus 49.2 (39.5-59.2) mU x (gHb)(-1)) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, sex, smoking status, or tumour cell types. However, more advanced disease (stage IV compared with stage IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicted SOD and GPx activities. In conclusion, nonsmall cell lung carcinoma in Chinese subjects is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis. 相似文献
2.
6-keto-prostaglandin F1a and thromboxane B2 were determined in order to obtain more information about the prostacyclin synthesis and thromboxane A2 release in 3- to 18-year-old healthy children and in offspring of parents who have had an acute myocardial infarction before the age of 45. The authors demonstrated a reduction of plasma prostacyclin synthesis in children with a positive family history of premature coronary arterial disease. Thromboxane levels in the affected adolescent boys were significantly lower compared with the controls. The ratio of thromboxane:prostacyclin in endangered children did not show a significant difference from that of healthy controls. These data indicate that prostaglandins are a definitive marker for identifying cardiovascular risk children. It must be supposed that in adolescence, only in boys, with a positive family history of premature coronary arterial disease, a compensatory mechanism exists to protect them from developing an imbalance in the regulation of prostaglandins. 相似文献
3.
V. van Casteren P. Leurquin A. Bartelds F. Gurtner V. Massari S. Maurice-Tison A.T. Vega R. Mak 《European journal of epidemiology》1993,9(2):169-175
This study describes a p. year international data collection on the demand pattern for HIV-antibody tests in general practice recorded by 6 sentinel networks in 5 European countries. The purpose of the recording was to evaluate the use of HIV-antibody testing by general practitioners and the demand for testing among the general population. Sentinel networks of general practitioners are a possible and available instrument for monitoring the perception of the HIV-test, and indirectly of the threat of the HIV-epidemic by the public and by the general practitioners (GPs). Differences were found between the countries in the frequency of testing, the person asking the test and the reason for testing. Possible explanatory factors, such as differences in the routine testing of specific groups, differences in the training and in the role of the GP, differences in the characteristics of prevention policy, are discussed. The European comparison also offers the opportunity to reflect on common medical practice in dealing with demands for HIV-tests. 相似文献
4.
Eighty-nine consecutive Chinese patients (69 males, 20 females) with acute myocardial infarction treated by 100 mg recombinant tissue-plasminogen activator (rt-PA) (7 intracoronarily, 82 intravenously) at 3.7 +/- 1.0 hours after onset, and intravenous heparin or dipyridamole therapy started at 3 hours, were studied prospectively. Their mean age was 59.6 +/- 10.6 years. Forty-six patients (51.7%) had anterior and 39 patients (43.8%) had inferior infarcts. Clinical evidence of reperfusion was seen in 63 patients (72.8%), while new complications included hypotension (5.6%), heart failure (6.7%), cardiac arrhythmias (76.4%), hematoma around vascular access sites (23.6%), melena (2.2%) and cerebral infarction (2.2%). Maximal changes in coagulation profiles were seen at 3 hours, including a decrease in fibrinogen (by 64.2%), an increase in FDP by 11.7 times and D-dimers by 4.4 times. Nine patients (10.1%) had recurrence of angina and 6 patients (6.9%) died due to pump failure (5) and reinfarction (1). Angiogram at 14 days confirmed TIMI (2 or 3) patency of infarct related arteries in 62/81 (76.5%) patients, with a mean global ejection fraction of 52.5 +/- 12.4%. Nearly all survivors could maintain class I-II functional status after discharge. The safety and promises of rt-PA for acute myocardial infarction in the Chinese were confirmed.
相似文献
5.
J. C. W. Mak H. C. M. Leung S. P. Ho F. W. S. Ko A. H. K. Cheung M. S. M. Ip M. M. W. Chan-Yeung 《Clinical and experimental allergy》2006,36(4):440-447
BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population. 相似文献
6.
We undertook an analysis of the hazard functions derived from results published by the Parkinson Study Group following their investigation of deprenyl. Our findings indicate that the action of deprenyl is transient rather than sustained. We also infer that this effect may be mediated through alleviation of symptoms rather than by neuroprotection. 相似文献
7.
Koon-Hou Mak 《European heart journal》2007,28(6):655-656
Myocardial infarction is an important public health problemworldwide. Rapid restoration of flow remains as the foundationfor life-saving treatment of patients with ST-segment elevationmyocardial infarction (STEMI). In Europe, it is heartening tonote that the utilization of reperfusion therapies was increasingly,with the proportion rising from 55.8% in 20002001 to63.9% in 2004, based on the first and second Euro Heart Surveysof Acute Coronary Syndromes, respectively.1 Notably, patientswere more likely to receive primary percutaneous coronary intervention(increased from 37 to 59% over the same period),1 probably becauseof the favourable results derived from 相似文献
8.
Robert H. K. Mak 《Pediatric nephrology (Berlin, Germany)》1998,12(8):637-642
Insulin and branched-chain amino acid (BCAA) metabolism was studied in 14 adolescents with uremia on hemodialysis. Glucose
tolerance was measured by intravenous glucose tolerance tests. Insulin sensitivity was measured by the euglycemia clamp technique.
Insulin secretion during constant hyperglycemia was measured by the hyperglycemic clamp technique. Fasting plasma BCAA concentrations
were compared with data from 8 adolescent controls, whereas insulin indices were compared with 8 young adults controls and
with published normal data in adolescents. The patients could be further sub-divided into two groups with respect to their
growth velocity standard deviation score (GVSDS). Group 1 consisted of 7 patients with GVSDS less than −2. This group demonstrated
insulin resistance, glucose intolerance, and low insulin secretion. This group also had low plasma valine, leucine, and isoleucine
concentrations compared with control values. Group 2 consisted of 7 patients with GVSDS more than −2. This group demonstrated
insulin resistance, but normal glucose tolerance and normal insulin secretion. Plasma valine, leucine, and isoleucine concentrations
in group 2 were not different from control values. Total plasma BCAA correlated with glucose tolerance index and with insulin
secretion, but not with insulin sensitivity. Growth failure in uremia is associated with glucose intolerance, hypoinsulinemia,
and low plasma BCAA concentrations. Impaired utilization of conventional energy sources leading to preferential oxidation
of BCAA may contribute to reduced anabolism and growth failure in uremia.
Received October 8, 1997; received in revised form February 3, 1998; accepted February 6, 1998 相似文献
9.
10.
The presence of blocking factors in Brugia malayi microfilaraemic patients 总被引:1,自引:0,他引:1 下载免费PDF全文
Serum from microfilaraemic patients have been shown to be unable to promote the antibody-dependent, cell-mediated adherence reaction to infective larvae of Brugia malayi in vitro. In this study, it was found that peripheral leucocytes from microfilaraemic patients were also incapable of promoting the adherence reaction even when incubated with serum of tropical pulmonary eosinophilia (TPE) patients. The TPE sera would normally promote the most intense adherence reaction. It was further shown that preincubation of normal human peripheral leucocytes with sera of microfilaraemic patients would similarly render them incapable of adherence. Such preliminary studies suggest that blocking factors may be present in microfilaraemic patients. 相似文献