Humans ; Occupational Health ; Occupational Health Services ; World Health Organization

Anniversaries and Special Events ; Education, Medical ; history ; History, 20th Century ; History, 21st Century ; Occupational Medicine ; history

China ; Health Occupations ; legislation & jurisprudence ; Health Personnel ; Humans ; Occupational Health ; legislation & jurisprudence ; Preventive Health Services ; legislation & jurisprudence ; Risk Factors

Cadmium ; adverse effects ; Dose-Response Relationship, Drug ; Environmental Exposure ; adverse effects ; Humans ; Occupational Exposure ; adverse effects ; Risk Assessment

Animals ; Benchmarking ; methods ; statistics & numerical data ; Dose-Response Relationship, Drug ; Humans ; Models, Statistical ; No-Observed-Adverse-Effect Level ; Risk Assessment ; methods ; statistics & numerical data ; Toxicology ; methods

Animals ; Cells, Cultured ; Male ; Phenols ; toxicity ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Sertoli Cells ; drug effects ; metabolism ; Steroidogenic Factor 1 ; genetics ; metabolism

Cadmium ; pharmacology ; Cells, Cultured ; Heat-Shock Proteins ; biosynthesis ; Humans ; Metallothionein ; biosynthesis ; Ubiquitin ; biosynthesis

Toxicology ; Translational Medical Research

Animals ; Cadmium Chloride ; toxicity ; Dose-Response Relationship, Drug ; Estradiol ; toxicity ; Female ; Organ Size ; drug effects ; Rats ; Rats, Sprague-Dawley ; Uterus ; drug effects ; pathology

OBJECTIVETo study the combined effect of fluoride and arsenate on the expression of SD rat osteoblastic osteoclast differentiation factor (ODF) mRNA and osteoprotegerin (OPG) mRNA.

METHODSOsteoblasts were obtained by enzymatic isolation from newborn SD rats. A factorial experiment was performed. Osteoblasts were exposed to NaF (0.5 mmolF/L, 4 molF/L) and Na3AsH2 (12.5 micromolAs/L and 200 micromolAs/L) separately or F plus As and cultured for 48 h. The gene expression of osteoblastic ODF and OPG was observed by RT-PCR.

RESULTSThe expression of ODF mRNA increased in F0.5, F4 groups compared with control group and two groups of F0.5As200, F4As200 compared with As200 group, and decreased significantly in groups of F4Asl2.5, F0.5As200, and F4AS200. The expression of OPG mRNA decreased in groups of F4, As200, F4As12.5, F0.5AS200, and F4AS200.

CONCLUSIONThe joint effect of fluoride and arsenate on the gene expression of ODF is antagonistic, while the combined effect on the gene expression of OPG is synergistic. F4, F4As12.5, and F0.5As200 promote bone resorption of rat osteoclasts, whereas F0.5As12.5 inhibits osteolytic effect of rat osteoclasts.

Animals ; Animals, Newborn ; Arsenates ; pharmacology ; Bone and Bones ; drug effects ; Cariostatic Agents ; pharmacology ; Fluorides ; pharmacology ; Gene Expression ; drug effects ; Hazardous Substances ; pharmacology ; Osteoblasts ; cytology ; drug effects ; Osteoprotegerin ; biosynthesis ; genetics ; RANK Ligand ; biosynthesis ; genetics ; Rats