[Frequency of protein C polymorphisms in Chinese population and thrombotic patients]

OBJECTIVE

To study the allelic frequencies of protein C(PC) polymorphisms in Chinese Han population and thrombotic patients.

METHODS

Two PC polymorphisms PC-1476A/T and PC3342T/G situated in exon 1 and exon 6 of PC were detected by PCR-SSCP silver stain. Ninty normal individuals and 105 patients with thrombosis were studied.

RESULTS

The frequencies of PC-1476A/T in normal individuals were obviously different from in Caucasians (0.867/0.133, 0.4/0.6), whereas the frequencies of PC-3342T/G were similar in Chinese and Caucasians (0.60/0.40, 0.59/0.41). The frequency distributions of the two polymorphisms were consistent with the law of Hardy-Weinberg and were in the mode of linkage disequilibrium. The frequences of rare alleles PC-1476T and PC-3342G were higher in thrombotic patients (0.21 and 0.46) than in normal controls (0.13 and 0.40). PC-1476T was especially high in CHD patients (0.243) (P < or = 0.05).

CONCLUSION

These results suggest that the two polymorphisms may be one of the genetic related factors in venous and arterial thrombosis.

Chronic hypoxemia selectively down-regulates 11beta-hydroxysteroid dehydrogenase type 2 gene expression in the fetal sheep kidney

The present study was designed to examine the effects of chronic fetal placental embolization on the expression of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) types 1 and 2, the intracellular enzymes responsible for the metabolism of glucocorticoids. Twelve instrumented fetal sheep were randomly allocated on Day 110 (term = 147 days) to either a control (n = 6) or embolized (n = 6) group. Embolized fetuses received daily injections of nonradioactive microspheres into the abdominal aorta for 21 days to decrease arterial oxygen content by 40-50% of the pre-embolization values. At the end of the experiment, fetal liver and kidney tissues as well as placental cotyledons were collected, and tissue levels of 11beta-HSD mRNA and activity were determined by standard Northern blot analysis and radiometric conversion assay, respectively. There was a 44% reduction (p < 0.01) in the level of renal 11beta-HSD2 mRNA in the embolized group as compared with the control group. Moreover, this reduction in mRNA was carried through to 11beta-HSD2 protein, since there was a corresponding decrease in the level of 11beta-HSD2 activity (4.5+/-0.2 vs. 2.9+/-0.1 pmol/min per milligram protein, p < 0.01). In contrast, levels of both 11beta-HSD1 mRNA and activity in the fetal liver remained unchanged. Moreover, both 11beta-HSD types 1 and 2 mRNA and activity in the placenta were not altered by the fetal placental embolization. In conclusion, chronic hypoxemia selectively inhibits renal 11beta-HSD2 mRNA expression and enzyme activity in the ovine fetus, which may contribute, at least in part, to the mechanisms leading to fetal hypertension.

[Spectroscopic diagnostic of atmospheric pressure argon microwave induced plasma]

Atmospheric argon microwave-induced plasma (Ar-MIP) sustained by a surfatron was obtained. Emission spectra and characteristics of argon metastable (1Sj) were studied with an optical multichannel analyer (OMA-3, 1460) under different experimental condition. Excitation mechanism of the plasma was discussed.

Hepatitis C in HIV-infected patients with and without AIDS: prevalence and relationship to patient survival

BACKGROUND

Limited information is available about the prevalence of hepatitis C virus in patients with human immunodeficiency virus in relation to specific risk factors or about the influence of hepatitis C virus coinfection on survival. This retrospective study addressed these questions.

METHODS

The study population consisted of 512 predominantly non-intravenous drug-using male homosexuals, 224 of whom had AIDS. Samples positive for hepatitis C virus antibody by second-generation enzyme immunoassay were further tested by means of strip immunoblot assay, and for hepatitis C virus RNA by means of polymerase chain reaction amplification. A randomly selected set of enzyme immunoassay-negative samples was also tested for hepatitis C virus RNA and, if hepatitis C virus RNA positive, by a second-generation recombinant immunoblot assay.

RESULTS

The prevalence of hepatitis C virus infection unaccounted for by intravenous drug use or transfusion was 11.7% by enzyme immunoassay, and 87% of sera positive by enzyme immunoassay were also positive by second-generation recombinant immunoblot assay or hepatitis C virus RNA analysis. Hepatitis C virus RNA was detectable in 53% of enzyme immunoassay-positive samples but in only about 1% of enzyme immunoassay-negative samples. Hepatitis C virus coinfection did not influence survival of HIV-infected patients with or without manifestations of AIDS.

CONCLUSIONS

Hepatitis C virus infection in nontransfused, non-intravenous drug-using patients with HIV infection is several times more prevalent than in volunteer blood donors, suggesting homosexual transmission of hepatitis C virus. About half of patients seropositive for hepatitis C virus antibody have detectable hepatitis C virus RNA, and serologically occult hepatitis C virus viremia is rare. Hepatitis C virus coinfection does not appear to adversely influence survival.

A study on the effect of lesions of area 7 of the parietal cortex on the short-term visual spatial memory of rhesus monkeys (Macaca mulatta)

This research is focused on the contribution of area 7 to the short-term visual spatial memory. Three rhesus monkeys (Macaca mulatta) were trained in the direct delayed response task in which 5 delay intervals were used in each session. When each monkey reached the criterion of 90% correct responses in 5 successive sessions, two monkeys underwent a surgery while the other one received a sham operation as a control. In the first stage of the surgery, bilateral areas 7a, 7b and 7ip of the parietal cortex of two monkeys were precisely lesioned. After 7 days of recuperation, the monkeys were required to do the same task. The average percentage of correct responses in the lesioned animals decreased from 94.7% to 89.3% and 93.3% to 82.0% respectively (no significance, P > 0.05, n = 2). In addition, the monkeys' complex movements were mildly impaired. The lesioned monkeys were found to have difficulty picking up food from the wells. In the second stage, bilateral area 7m was lesioned. In the 5 postoperative sessions, the average percentage of correct responses in one monkey, with a relatively precise 7m lesion, decreased from 94.7% to 92.2% (no significance, P > 0.05), while the other monkey, with widely spread necrosis of lateral parietal cortex, showed an obvious decline in performance, but still over the chance level. After 240 trials this monkey reattained the normal criterion.(ABSTRACT TRUNCATED AT 250 WORDS)

[A preliminary report on the investigation of medicinal plant resources in the Liupan Mountains of Ningxia Hui Autonomous Region]

In this paper, 423 species of medicinal plants belonging to 94 families in Liupan Mountains of Ningzia Hui Autonomous Region have been reported, of which 403 species belonging to 79 families are medicinal spermatophytes. The paper may serve as a reference for medical authorities in developing and utilizing plant resources.