Objective: To observe the level of pro-opiomelanocortin (POMC) mRNA expression in the hypothalamic arcuate nucleus in young and senile rats. Methods: POMC mRNA was determined with in situ hybridization, the hybridization signals and areas of POMC mRNA-positive cells were measured with computer image analysis system. Results: Compared with young rats, average gray values of POMC mRNA-positive neurons in the hypothalalmic arcuate nucleus and near region in the senile rats decreased, but the numbers of POMC mRNA-positive neurons did not change significantly. Conclusion: The decrease of POMC mRNA expression level in individual neurons in hypothalamic arcuate nucleus of senile rats is one of the causes that decrease the expression of peptides-derived from POMC gene.

Objective To study the role of Anopheles anthropophagus in malaria transmission and transmission threshold so as to provide basis for vector surveillance and malaria control strategy. Methods Parasitological and entomological methods were used in the investigation at 5 villages of Xinyang City, Henan Province. Results From July to August, 1999, 74 febrile cases (10\^9% of the total population) were examined. Among them 50 were infected, the incidence in the population of surveyed spots was 7\^4%. Active detection was made in another randomly selected two villages and found that the parasite rate in the inhabitants was 2\^0%, and the positive rate of IFA was 8\^4%. Only vivax malaria was detected. An.anthropophagus and An.sinensis were collected, with An.anthropophagus as the predominant one in human dwellings. The estimated man\|biting rate and the human blood index were 4\^9388 and 0\^7858 respectively. The vectorial capacity of An. anthropophagus was 5\^5296. The critical man\|biting rate of An.anthropophagus was 0\^2407 as calculated by the formula (ma=-rlnP/abP\+n) according to Macdonald′s model.The local man\|biting rate was 20 times higher than that of the critical man\|biting rate. Conclusion The results demonstrated that An.anthropophagus is the principal vector in malaria transmission in the area. The findings imply that the critical man\|biting rate is of practicable importance in vector surveillance.

"Common Drive" is presented recently as a new concept used to explore the control mechanism of neuromuscular system. In this paper, the average firing rate (FR) of the motor unit action potential (MUAP) is estimated by means of decomposition technique for needle electromyographic (NEMG) signals obtained from elbow joint agonist-antagonist muscle pair with constant contraction force. The change tendency and correlation of the average FR with time are studied. The results of the experiment show that, no matter flexion or extension of the elbow joint, the average FR of both motor units(MUs) in the couple of agonist and antagonist descends with time, and the variations of their amplitude and fluctuation are highly correlated. This indicates that when two antagonist muscles are activated simultaneously to stiffen a joint, the nervous system views them as one unit and controls them in similar fashion. It also confirms the existence of "Common Drive" phenomenon at joint level.
Action Potentials ; physiology ; Electromyography ; Humans ; Motor Neurons ; physiology ; Muscle Contraction ; physiology ; Signal Processing, Computer-Assisted

Objective To observe the effect of tumor necrosis factor-α( TNF-α) on islet cell apoptosis and TXNIP expression.Methods INS-1 cells were cultured in vitro, treating with TNF-α(0, 1, 5, 10 and 20 mg/L).We tested the effect of TNF-αon cell viability by CCK-8.INS-1 cells were treated with TNF-α( 5 mg/L, 24 h) for the proper concentration and incubation time; mRNA expression of TXNIP and ChREBP were measured by real-time PCR;in addition, protein levels of TXNIP , ChREBP and FOXO1 were analyzed by Western blot .Results TNF-αdecreased the survival rate of INS-1 cells in a dose-dependent manner ( P<0.05 ) , and induced apoptosis;protein and mRNA expression of TXNIP and ChREBP were significantly higher than that in control group ( P<0.05 );while the expression of protein level of FOXO 1 was down-regulated .Conclusions TNF-αinduces apoptosis in INS-1 cells and aggravates the cells damage .

0.05).Moreover,the growth curves of the two kinds of cells were similar.Con- clusions The cell growth properties of cultured transplanted rabbit SMG are similar to that of normal SMG,the cytobiological charac- teristic of transplanted autologous free rabbit SMG are not changed evidently.

The mutagenic effects of microwave and chromium trioxide (CrO(3)) on Vicia faba root tip were studied. Micronucleus assay and chromosomal aberration assay were used to determine the mitotic index, the micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells induced by microwave and CrO(3). The results showed that the micronucleus frequency decreased, and that the mitotic index and chromosomal aberration frequency showed linear dose responses to CrO(3), in treatment of microwave for 5 s. In microwave of 25 s, the mitotic index decreased, the micronucleus frequency and chromosomal aberration frequency increased with increase of CrO(3) concentration. We concluded that microwave and CrO(3) had antagonistic effect on the mitotic index of Vicia faba root tip cells, but had synergetic effect on micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells.
Cells, Cultured ; Chromium Compounds ; toxicity ; Chromosome Aberrations ; drug effects ; radiation effects ; Chromosomes, Plant ; drug effects ; radiation effects ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Radiation ; Micronucleus Tests ; Microwaves ; adverse effects ; Plant Roots ; drug effects ; genetics ; radiation effects ; Vicia faba ; drug effects ; genetics ; radiation effects

Biomarkers ; analysis ; Child ; Humans ; Mass Spectrometry ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Wilms Tumor ; metabolism

OBJECTIVETo investigate abnormal liver function associated with polymorphism of GSTT1, GSTM1 and CYP2E1 in workers exposed to N, N-dimethylformamide.

METHODSSixty-nine workers with abnormal liver function in a synthetic leather factory were recruited as case. One hundred and twenty five control subjects with similar work tasks were selected from the same factory. Genotypes for GSTT1 and GSTM1 were determined by multiplex PCR, and for CYP2E1 PstI by PCR-RFLP assay.

RESULTSThe frequency of positive GSTM1 was 59.42% in cases and 38.40% in control, with an odds ratio (OR) of 2.34,95% CI: 1.29-4.29 (P=0.005). For GSTT1 and CYP2E1 PstI, the frequencies of genotypes showed no significant difference between case and control.

CONCLUSIONGSTM1 positive genotype may be genetic risk factors for development of abnormal liver function in workers exposed to N, N-dimethylformamide.

Adult ; Chemical and Drug Induced Liver Injury ; etiology ; genetics ; Cytochrome P-450 CYP2E1 ; genetics ; Dimethylformamide ; adverse effects ; Female ; Genotype ; Glutathione Transferase ; genetics ; Humans ; Male ; Occupational Exposure ; adverse effects ; Polymorphism, Genetic

OBJECTIVETo investigate the hepatotoxic effects of N, N-dimethylformamide (DMF) in the workers of a synthetic leathers factory, and the effects on liver function of covariates such as alcohol consumption and other factors.

METHODSThe workers were classified into three groups (low, high and the control) by the concentration of DMF in workplace which was determined in the past two years. A questionnaire was drawn up for relevant demographic characteristics and other factors influencing liver function. The bloods were collected for laboratory test which included parameters especially relevant to the liver (ALT AST and gamma GT).

RESULTSLow and high-exposure groups were significantly associated with elevated ALT and gamma GT, and high-exposure group was significantly associated with elevated Liver index. Modeling by stepwise regression analysis demonstrated that high concentration of DMF and BMI were associated with and elevated ALT, gamma GT and Liver index, besides DMF and BMI, the elevation of ALT was also associated with high TRIG. AST was only associated with alcohol consumption. The AST/ALT ration < 1 was present in 86.7% of the exposure workers of liver function abnormal.

CONCLUSIONDMF can cause liver function alternations even if air concentration of DMF was below PC-TWA. Besides the levels of DMF exposure, obesity (BMI) and alcohol consumption are covariates alternating liver function. Liver index can be a parameter for assessment liver function, and the AST/ALT ration < 1 may serve as markers of risk in health screening programs.

Adult ; Alanine Transaminase ; blood ; Dimethylformamide ; toxicity ; Female ; Humans ; Liver ; metabolism ; physiopathology ; Liver Function Tests ; Male ; Occupational Exposure

OBJECTIVETo investigate the effects of ST1571 on the development of dendritic cells (DC) derived from bone marrow mononuclear cells of patients with chronic myeloid leukemia (CML).

METHODSBone marrow mononuclear cells (BMMNC) from CML patients and healthy volunteers were cultured initially using multiple cytokine combinations as follows: recombinant human granulocyte/ macrophage colony-stimulating-factor (rhGM-CSF) plus recombinant human interleukin-4 (rhIL-4) as CML and normal control groups, rhGM-CSF plus rhIL-4 and ST1571 as CML experimental groups, and from day 8 recombinant human tumor necrosis factor-alpha ( rhTNF-alpha) was added to stimulate DC maturation. The morphologic features of cells were observed by Wright's staining and phenotypes were assessed by flow cytometry. Cytogenetic analysis was performed by fluorescence in-situ hybridization (FISH), and the antigen-presenting function was assayed by mixed lymphocyte reaction (MLR). The concentration of VEGF was detected by ELISA.

RESULTSCML experimental groups treated with STI571 displayed morphological features similar to those of control groups with delicate membrane projections. However, in comparison with the CML control groups, the CML experimental groups showed an increased expression of CD80, CD86, CD83 and HLA-DR and showed more intense abilities of allogeneic antigen presentation, which were similar to those of normal control groups. FISH confirmed that DCs of both CML, groups were of leukemic origin. The concentration of VEGF was dramatically reduced in CML experimental groups.

CONCLUSIONIn vitro, STI571 promotes the activation/maturation of DCs derived from BMMNCs of patients with CMI, and decreases VEGF production by the leukemic cells. The promotion of DC maturation may be partially due to decreased inhibitory effect of VEGF.

Adult ; Antigens, CD ; metabolism ; Benzamides ; Bone Marrow Cells ; drug effects ; metabolism ; pathology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dendritic Cells ; drug effects ; metabolism ; pathology ; Female ; Flow Cytometry ; Fusion Proteins, bcr-abl ; genetics ; metabolism ; HLA-DR Antigens ; metabolism ; Humans ; Imatinib Mesylate ; In Situ Hybridization, Fluorescence ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; blood ; pathology ; Male ; Middle Aged ; Piperazines ; Pyrimidines ; pharmacology ; T-Lymphocytes ; drug effects ; metabolism ; pathology ; Vascular Endothelial Growth Factor A ; metabolism