Objective To investigate the state of drinking water defluorination project in Dagang district and study urinary fluoride levels and detect dental fluorosis of children aged 8 to 12, and to provide scientific basis for prevention and control of fluorosis. Methods Five defluorination projects in rural streets (towns) with highfluoride water and 2 urban water supply projects were choosen to investigate the running status in Dagang district Tianjin in 2009. Five rural and 2 urban schools were choosen to select 100 children aged 8 to 12 (for gender, age matched) in each primary school to study urinary fluoride levels and detection of dental fluorosis. Results A total of 66 defluorination projects in 73 villages were surveyed, among which 61 projects actually worked normally with using rate 92.4%(61/66). Water qualification of all projects could not be ensured due to direct project managers'lack of necessary expertise. In 2009, water qualification rate were 39.3%(24/61 )among the project normally used,with highlighted problem of biological pollution. A total of 490 children aged 8 - 12 in 5 rural towns were surveyed,dental fluorosis rate were 90%(441/490), and dental fluorosis index were 1.82. A total of 207 children aged 8 - 12in 2 urban areas were surveyed, the detection rate of dental fluorosis was 49.8%(103/207), and dental fluorosis index were 0.86. The urinary fluoride level of 230 children aged 8 - 12 in the 5 villages were surveyed. The Range of geometric mean of urinary fluoride were 1.82 - 2.70 mg/L. The urinary fluoride of 102 children aged 8 - 12 in the 2 urban area were surveyed. The Range of geometric mean of urinary fluoride were 1.53 - 1.72 mg/L. Conclusions There was phenomenon of high coverage, low utilization rate and less water consumption in the villages of Dagang district, Tianjin drinking water defluoridation projects, thus the health effects of the projects was minimum.Significant health effects is found in the defluorination projects in the urban areas with high coverage and high utilization rate. Studying new water improvment methods and new forms of water supply system is urgent for solving the problems met in the ineffective water defluorination project.

Objective To analyze the classification,MR manifestations,and the pathological basis of solitary necrotic nodule of the liver(SNN)in order to evaluate MRI as a diagnosing tool Methods The MR appearances of 9 cases with pathologically proved SNN were analyzed and correlated with the classification and pathological appearances.Relevant literature was reviewed.Results(1)Simple coagulative necrosis type(5 cases):The signal of lesions was hypo-intense or iso-intense on both T_1-and T_2- weighted images.After Gd-DTPA administration,the internal part of the lesions showed no enhancement,while the thin capsule of the lesions demonstrated mild or moderate delayed enhancement. These lesions,proved by pathology,were composed of central coagulative necrotic core and a peripheral hyaline fibrosis capsule.(2)Coagulative necrosis aceompanied by liquefactive necrosis type(1 case):On T_1-weighted images,the signal of hypo-intensity was found within these lesions and even lower signal intensity was found in the central area of larger lesions.On T_2-weighted images,the lesions had a bright core and a peripheral hypointensive or isointensive area.After Gd-DTPA administration,the internal part of the lesions showed no enhancement,while the thin capsule of the lesions demonstrated mild or moderate delayed enhancement.These lesions had a central coagulative necrosis core interleaved by slit- like liquefactive necrosis foci,and peripherally a thin capsule of hyaline fibrosis proved by pathology.(3)Multi-nodular fusion type,(3cases):On T_1-weighted images,the lesions were of hypointensive or isointensive signal and had multiple septa of isointensive signal.On T_2-weighted images,the lesions were of hypointensive or isointensive signal and had multiple septa of hyperintensive or isointensive signal.After Gd-DTPA administration,No enhancement was found except mild or moderate delayed enhancement found in the thin capsule and septa.These lesions were composed of central coagulative necrosis area and a peripheral hyaline fibrosis capsule with multiple internal septa proved by pathology.Conclusion MRI apperances can reflect the classification and pathological features of solitary necrotic nodule of the liver.

China ; epidemiology ; Cholera ; epidemiology ; Disease Outbreaks ; Humans

OBJECTIVETo gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfunction.

METHODSMice were exposed to whole body 2100 MHz microwaves with specific absorption rates (SARs) of 0.45 W/kg, 1.8 W/kg, and 3.6 W/kg for 1 hour daily for 8 weeks. Differentially expressing genes in the brains were screened using high-density oligonucleotide arrays, with genes showing more significant differences further confirmed by RT-PCR.

RESULTSThe gene chip results demonstrated that 41 genes (0.45 W/kg group), 29 genes (1.8 W/kg group), and 219 genes (3.6 W/kg group) were differentially expressed. GO analysis revealed that these differentially expressed genes were primarily involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, cellular component organization, etc. KEGG pathway analysis showed that these genes are mainly involved in pathways related to ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling. Construction of a protein interaction network identified several important regulatory genes including synbindin (sbdn), Crystallin (CryaB), PPP1CA, Ywhaq, Psap, Psmb1, Pcbp2, etc., which play important roles in the processes of learning and memorye.

CONCLUSIONLong-term, low-level microwave exposure may inhibit learning and memory by affecting protein and energy metabolic processes and signaling pathways relating to neurological functions or diseases.

Animals ; Computational Biology ; Gene Expression ; radiation effects ; Learning ; Memory ; Mice ; Microwaves ; Reverse Transcriptase Polymerase Chain Reaction