[Survey on the current status of drinking water supply, latrines and the health knowledge of residents in the remote rural areas of several provinces of China]

A survey on the current status of drinking water supply, latrines and the health knowledge of residents in the remote rural areas of the southwest and northwest of China was reported. A stratified cluster sampling method was adopted in the survey. 83 poverty countries and 74,900 families were involved in the survey and four hundred thousands data were obtained by home visiting. The results showed that the coverage of rural latrines, sanitary latrines and safe night-soil disposal in the surveyed regions had reached 90.0%, 6.0% and 25.0% of populations respectively. The coverage of safe-drinking water was 57.6% of homes and no adequate supply of drinking water was 13.2% of homes; Many responders in the survey did not have the knowledge related to intestinal infectious diseases. There were 42.3% of them not knowing that night-soil was the source of infectious diseases, 56.2% of them not knowing that fly could spread infectious diseases and 70.0%-82.7% of them not knowing the ways of spreading intestinal infectious disease.

[Wavelength selection in management of central serous chorioretinopathy]

OBJECTIVE

To compare the effects of three kinds of laser wavelength in management of central serous chorioretinopathy (CSCR).

METHOD

89 patients with CSCR were randomly divided into three groups according to different wavelengths used. Visual acuity, fundus, fundus fluorescein angiography (FFA), light sensitivity, central visual field were performed before and after laser therapy.

RESULT

Compared with red and green wavelength groups, in yellow group the visual acuity, light sensitivity were improved more significantly (P < 0.05), and the disease course was shortened, the effects in recurrence rate were similar in the three wavelength groups.

CONCLUSION

In the three kinds of waves, yellow and red have similar and positive effects in the treatment of CSCR.

[Determination of cortisol in plasma and 24-hour urine of patients with central serous chorioretinopathy]

OBJECTIVE

To study the cortisol levels in patients with central serous chorioretinopathy (CSCR).

METHODS

Endogenous cortisol levels in plasma and urine were determined in 44 patients with CSCR by radioimmunoassay and chromatography, and their results were compared with that of 41 controls.

RESULTS

In acute CSCR, the mean values of the plasma cortisol (296.53 +/- 77.03) ng/ml and 24-hour urine 17-hydroxysteroids (the major metabolite of cortisol metabolism) (12.08 +/- 4.82) mg/24 h revealed significantly higher values in the patient group (P < 0.05).

CONCLUSIONS

Increased levels of endogenous cortisol play a role in the development of CSCR.

[The influence of salvia miltiorrhiza and tetramethyl pyrazine on DNA content of cicatricial fibroblasts and its cellular cycle]

In order to study the mechanism of the inhibitory effect of salvia miltiorrhiza (SM) and tetramethyl pyrazine (TP) on scar fibroblast, the DNA content of fibroblast and the all distribution in cellular cycle was measured by FCM. The hypertrophic scar tissue of chest was chosen for primary culture of fibroblast. Then this cultured cell was reacted with SM and TP. FCM was used to measure the DNA index and duration of cellular cycle. The results showed that: 1. SM and TP had little effect on DNA index, but when the concentration of drugs reached the threshold, they could increase the amount of fibroblasts in C2-M stage and the duration of G2-M stage was prolonged; 2. TP could also prolong the duration of S-stage; 3. SM and TP could prolong the multiplication time of fibroblasts and this effect was correlated postively with the dosage of drug. The conclusions were that the inhibitory effect of SM was the result of inhibiting the mitosis of cells and the cellular cycle be at a standstill in G2-M stage. The inhibitory effect of TP was due to the inhibition of synthesis and duplication of DNA and cellular mitosis, and the cellular cycle was also at a standstill in G2-M stage.

[The inhibitory effect in vitro of salvia miltiorrhiza and tetramethyl pyrazine on the growth of fibroblasts]

In order to investigate the inhibitory effect of salvia miltiorrhiza (SM) and tetramethyl pyrazine (TP) on scartricial fibroblast, the hypertrophic scar tissue of chest was chosen for culture of fibroblasts, and the influence of SM and TP on fibroblasts was observed, The effect of the drugs on the growth of fibroblasts, on DNA synthesis of fibroblasts and on mitosis index of fibroblasts were all determined quantitatively. The results showed: 1. SM and TP could inhibit significantly the growth of the fibroblasts, the inhibitory effect was irreversible when the concentration of the drugs reached 5 mg/ml and 500 micrograms/ml respectively; 2. SM and TP could inhibit the absorption of 3H-TdR and this effect was correlated positively to the dosage of the drugs and; 3. SM and TP could reduce the mitosis index of fibroblasts. It was concluded that SM and TP had definite depressive effect on growth of fibroblasts which was correlated positively with the concentration of drugs and duration of application. The inhibitory effect of the drugs on fibroblasts was mainly through inhibition of synthesis of DNA.

[Advances in the research on repairing cartilaginous defects of synovial joint]

The repair of defects of articular cartilage has continued to be a difficult problem. This article provided a collective review from literature pertaining to the advances gained in the repair of cartilaginous defects. In the spontaneous repair, if the defect of the cartilage was less than 3 mm, might result in complete or partial repair, but in those the diameter was more than 3 mm, the defect could not be repaired by normal cartilage. Although the cartilaginous autograft could give good result, but it could not be widely applied because short of supply of the autogenous cartilage. Cartilagious allograft could not be taken to repair cartilaginous defect because of reaction from tissue rejection. The transplantation of periosteal or perichondral graft had been tried but was eventually abandoned because of poor long-term result. The transplantation of free chondrocytes might be a method of hope. In general, transplantation of free chondrocytes into the cartilaginous defect will be lost. The supply of autogenous chondrocytes was very limited, and the heterogenous chondrocytes would inflict immunoreaction after being transplanted. In late of 1980, a new concept of tissue engineering was proposed. The problem that a scaffold of appropriate material which could hold the free chondrocytes in place from being lost might undergo proliferation and differentiation into new cartilage was far from being solved. Although tissue engineering still had various problems needed further investigation, but it will probably be the main direction of development in this field.

[Culture of chondrocytes seeded onto chitin scaffoldings coating with different materials: experimental study]

OBJECTIVE

To find the possibility of chitin used as scaffolds in tissue engineering.

METHOD

Chondrocytes were cultured when they were seeded onto chitin meshcoated with polylactic acid (PLA) lecithin (LEC) and poly-l-lysine (PLYS). With light microscope and scanning electron microscope, the scaffolds in hydrophilia and absorptivity to chondrocytes and the function of the cells were observed.

RESULT

LEC can change the hydrophilia of scaffolds. PLYS can strengthen the absorptivity of the scaffolds. and promote the matrices production of chondrocytes.

CONCLUSION

The chitin coated with LEC and PLYS can be used as scaffolds in tissue engineering.

Expression of germ cell nuclear factor (GCNF/RTR) during spermatogenesis

Germ cell nuclear factor (GCNF/RTR), a novel orphan receptor in the nuclear receptor superfamily of ligand-activated transcription factors, is expressed predominantly in developing germ cells. In several mammalian species two GCNF/RTR mRNAs are present in the testis, with the smaller 2.3-kb transcript generally expressed at higher levels than the larger 7.4- or 8.0-kb transcript. In both the mouse and rat, the 2.3- and 7.4-kb GCNF/RTR transcripts were detected in isolated spermatogenic cells, but not in Sertoli cells. Expression of these transcripts is differentially regulated, with the larger 7.4-kb mRNA appearing earlier during testicular development. The major 2.3-kb transcript is expressed predominantly in round spermatids in the mouse and rat. In situ hybridization studies in the rat demonstrated that GCNF/RTR transcripts reach maximal steady-state levels in round spermatids at stages VII and VIII of the spermatogenic cycle, and then decline abruptly as spermatids begin to elongate. RNase protection assays were used to predict the 3' termination site of the 2.3-kb transcript. An alternative polyadenylation signal (AGUAAA) was identified just upstream of this termination site. These studies suggest that GCNF/RTR may regulate transcription during spermatogenesis, particularly in round spermatids just prior to the initiation of nuclear elongation and condensation.

Cadmium exposure among residents in an area contaminated by irrigation water in China

River water used to irrigate arable land in Dayu County, Jiangxi Province, China, is polluted with cadmium from tailings and the wastewater of tungsten ore dressing plants. From information about the date on construction of ore dressing plants and an analysis of the annual growth rings of trees, we deduced that local residents have been exposed to cadmium for at least 25 years. Cadmium exposure was estimated based on a meal survey, which indicated that 99.5% of the oral cadmium intake came from rice and vegetables grown locally. The average oral intake of cadmium was calculated to be 367-382 micrograms/ day. Smokers had additional exposure from locally grown cadmium-containing tobacco. Cadmium concentrations in samples of urine (11 micrograms/g creatinine), blood (12 micrograms/l) and in the hair (0.11 microgram/g) of persons in the exposed area were high. The cadmium exposure lies in a range that can be considered to cause adverse renal effects in the long term.

[Experimental study on adipocyte culture in vitro]

The adipocyte belongs to a kind of end cells. Most people take a skeptical attitude to its ability of proliferation in vitro. Based on foreign scientists' experience in this aspect. We isolated rats' adipocytes with percoll-density-gradient procedure. Using compound medium of DMEM and F12 with glucocorticoid, insulin and basic fibroblast growth factor (bFGF), we have succeeded in culturing fat cells in vitro.