Genetic damage of mammalian cells induced by nickel-refining fumes / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effects of two kinds of nickel-refining fumes on DNA damage of NIH/3T3 cell and the difference.</p><p><b>METHODS</b>NIH/3T3 cells were treated by two kinds of nickel fumes collected from smelting furnace and refining workshop of a nickel-smeltery, and PBS taken the place of nickel-smelting fumes was used as negative control. Several hours later, the cytotoxicity of on NIH/3T3 cells was detected with MTT colorimetric assay, and the DNA damage was also measured by comet assay (single cell gel electrophoresis).</p><p><b>RESULT</b>With the extension of exposure time and increasing of concentration, the living rate of NIH/3T3 cells was decreased; the tail rate, tail extent moment and tail DNA percent of NIH/3T3 cell induced by these two refining fumes were increased. After cells were treated with 100.00 microg/ml of nickel-smelting fume for 48 h, the living rate of NIH/3T3 cells was 24.5% and 26.5% respectively. The tail length of NIH/3T3 cell induced by these two refining fumes was not significant difference. Tail DNA percent of NIH/3T3 cell induced by smelting furnace fume was higher than negative control group (P < 0.05). The tail rate, and tail DNA percent (except 12.5 microg/ml and 50.0 microg/ml treated 2 h group) of NIH/3T3 cell induced by refining workshop fume was higher than negative control group (P < 0.05).</p><p><b>CONCLUSION</b>Nickel-smelting fume could depress the survival rate of NIH/3T3 cells, and induce different degree DNA damage of NIH/3T3 cell.</p>

Screening of differentially expressed genes in the hypothalamus of a rat neuropathic pain model following sciatic nerve injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neuropathic pain is induced by injury or disease of the nervous system. Most studies have so far focused only on a few known molecules and signaling pathways among neurons. However, all signal transmissions involved in neuropathic pain appear to be an integral system at different molecular levels. This study was designed to screen the differentially expressed genes of the hypothalamus in chronic constriction injury (CCI) rats and analyze their functions in developing neuropathic pain.</p><p><b>METHODS</b>Ten adult female Sprague-Dawley rats ((200 +/- 10) g) were used in experimental group and sham group (n = 5 in each group). Mechanical allodynia tests were performed to ensure that the CCI rat model was constructed successfully. Total hypothalamus RNAs were isolated from each group. Forward suppression subtractive hybridization (SSH) library of rat hypothalamus was constructed and up-regulated cDNA clones at neuropathic pain states were obtained via suppressed subtractive hybridization technique and the functions of these genes were analyzed bioinformatically.</p><p><b>RESULTS</b>Mechanical allodynia tests showed that the experimental rats had a significantly reduced mechanical allodynia threshold 3 to 13 days after CCI vs sham surgery rats (P < 0.01), indicating that the model was successful. Forward SSH library of the rat hypothalamus was constructed successfully and 26 over-expressed expression sequence tags (ESTs) were obtained from these up-regulated cDNA clones.</p><p><b>CONCLUSION</b>Twenty-six up-regulated genes, involved in the regulation of cell cycle and apoptosis, signal transduction, and neuroprotection, may play key roles in decreasing mechanical withdraw thresholds in CCI rats, which implicates a multidimensional and integrated molecular mechanism at gene level in developing neuropathic pain with the supraspinal contributions.</p>

The cytotoxicity of nickel-refining dusts for chinese hamster lung cells and effects on gap junctional intercellular communication / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the cytotoxicity of the nickel-refining dusts for Chinese hamster lung (CHL) cells and the effects of nickel-refining dusts on the gap junctional intercellular communication (GJIC) of CHL cells.</p><p><b>METHODS</b>The cytotoxicity of the nickel-refining dusts for the CHL cells was determined in two nickel-refining dusts samples with the CHL cells as the target cells by MTT method while the effects of nickel-refining dusts on the CJIC of the CHL cells were investigated using the scrape-loading and dye transfer (SLDT) technique.</p><p><b>RESULTS</b>There were no significant difference in the CHL proliferation between all dosage groups in the two samples and the control group at 6 and 12 hours (P > 0.05). The survival rate of cells in all dosage groups were all decreased at 36 hours (P < 0.05), presenting the dosage-reaction relationship and the time-reaction relationship. IC(50) was 21.36 and 23.07 micro/ml for the two samples respectively at 36 hours. Compared with the control group, the transport of Lucifer Yellow (LY) from the injury line to the adjacent cells was decreased when the CHL cells were treated with nickel-refining dusts of 25.00, 50.00 and 100.00 microg/ml (P < 0.01).</p><p><b>CONCLUSION</b>The nickel-refining dusts have cytotoxicity for the CHL cells cultivated in vitro, can inhibit the growth of the cells and at a certain concentration can inhibit the GJIC function of CHL cells.</p>

Clinical study on method of "tonifying the lung to check the liver" for treatment of chronic cholecystitis / 中国针灸

<p><b>OBJECTIVE</b>To evaluate the significance of method of "tonifying the lung to check the liver" for treatment of chronic cholecystitis.</p><p><b>METHODS</b>Forty cases were randomly divided into a treatment group and a control group. The treatment group were treated with acupuncture and moxibustion by the method of "tonifying the lung to check the liver", and the control group with routine moxibustion.</p><p><b>RESULTS</b>After treatment of one day, pain improved significantly in the two groups (P < 0.001), with no significant difference between the two groups; and 15 days after treatment, the treatment group was superior to the control group in the improvement of pain.</p><p><b>CONCLUSION</b>TCM syndrome differentiation has an important significance in clinical acupuncture and moxibustion, and the therapeutic principle "tonifying the lung to check the liver" in classical TCM theories is of scientific basis.</p>

Experimental study on the DNA damage of NIH/3T3 cells induced by nickel-refining dusts / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effects of nickel-refining dusts on DNA damage in mouse NIH/3T3 cell.</p><p><b>METHOD</b>DNA damage of mouse NIH/3T3 cell induced by two nickel-refining dust samples was determined with single cell gel electrophoresis (SCGE) technique.</p><p><b>RESULTS</b>(1) Under the condition of the same treatment time, the tailed cell (%) of NIH/3T3 cells increased with the increase in doses of nickel-refining dusts (35.5%, 69.7%, 85.2%, 41.3%, 75.7%, 89.2% respectively except for sample 2, 50 microg/ml, 24 h group), and DNA strand breaks reached the peak value at 4 h of exposure; (2) When we treated the NIH/3T3 cells with the same dose of nickel-refining dusts, the tail rate at 4 h was higher than those at 2 h and 24 h of exposure; (3) Both sample 1 and sample 2 with different doses of nickel-refining dusts could induce higher comet tail, DNA%, tail length (except for 12.5 microg/ml), extent of TM (except for sample 1, 12.5 microg/ml) than in control group (P < 0.05). The DNA damage range was significantly increased in different tested doses of nickel-refining dusts and the damage range reached the peak value when the cells were treated for 4 h.</p><p><b>CONCLUSION</b>Nickel-refining dusts could induce different degree DNA damage in NIH/3T3 cells.</p>