ABSTRACT
Objective To master the level of iodine nutrition among population in Jiangxi province,and to provide a scientific basis for establishing the strategy for prevention and control of iodine deficiency disorders (IDD).Methods Retrospective method was adopted to analyze the goiter rate and frequency distribution of urinary iodine of children aged 8-10,the qualified rate of iodized salt,the coverage rate of iodized salt and the consumption rate of qualified iodized salt in residents of Jiangxi province from 1995 to 2010.The method of correlation analysis was used to analyze the relationship between goiter rate of children (by palpation) and the qualified rate of iodized salt,iodized salt coverage rate and residents consumption rate of qualified iodized salt.Results The goiter rates (measured by the method of palpation) of children aged 8-10 were down from 40.17％(482/1200) in 1995 to 0.80％(16/2000) in 2010(x2 =4.864,P＜ 0.05).The median of urinary iodine of children was higher than 200 μg/L; the proportion of people whose urinary iodine content higher than 300 μg/L was above 25.00％ and the highest propoaion was up to 58.01％ (210/362) between 1995-2010.The minimum median of salt iodine was 17.77 mg/kg in 1995,and 29.30-39.10 mg/kg in other years.The qualified rates of iodized salt,the iodized salt coverage rates and the consumption rates of qualified iodized salt increased from 43.58％(452/1037),86.42％(1037/1200) and 37.67％(452/1200) in 1995 to 97.95％ (1916/1956),99.95％(1956/1957) and 97.90％(1916/1957) in 2010,respectively; there was a growth trend over the years(x2 =5.240,6.118,5.631,all P ＜ 0.05).The goiter rates of children were related to the qualified rates of iodized salt,the iodized salt coverage rates and the consumption rates of qualified iodized salt,and the correlation coefficient(r) was-0.833,-0.881 and-0.918 (all P ＜ 0.05),respectively.Conclusions The level of iodine nutrition among residents in Jiangxi province has already gone beyond the appropriate level,and the iodine concentration in salt should be cut to ensure the appropriate iodine nutrition level among people.
ABSTRACT
Objective To investigate the fluctuation of the iodine deficiency disorders(IDD) through continuous monitoring on it. Methods During 2005-2008, 10 monitoring countis (city,district) of IDD were selected in Jiangxi Province. Five townships were selected in each monitoring county, one school was selected in each townships, and 40 students in 8-10 years old from each school were selected to inspect their thyroid glands and determined the idodine content of salts from their home. Among the 40 students, 20 of which were selected to determine the intelligence quotient(IQ) and 6 of which were selected to determine urine iodine. Thirty pregnant women were also selected to determine the urine iodine in each monitoring county. Twenty students of 5th grade in each school and 5 housewives living nearby the school were selected to carry out the questionnaire survey of health education about IDD. Results Monitoring results showed the average goiter rote of 8-10 years old students was between 2.00% and 4.60% during 2005-2008. The rate of IQ of the students higher than 90 was all above 76% each year. The median of urine iodine of students and pregnant women was higher than 100 μg/L, and the proportion of people whose urine iodine content was lower than 50 μg/L was below 4% each year. The rate of inhabitant taking qualified idodine salt wasn't lower than 95%. The pass rate of the questionnaire survey of health education about IDD was between 11.67% and 43.50% in students and 92.50%-99.60% in housewives. Conclusions The situation of iodine deficiency in Jiangxi Province has been greatly improved, reaching the standard of eliminating IDD.
ABSTRACT
<p><b>BACKGROUND</b>This study transferred a recombinant gene encoding human insulin like growth factor-1 (hIGF-1) into modified primary skeletal myoblasts with a retroviral vector (pLgXSN) and determined whether the hIGF-1 promoted growth of skeletal muscle in rat.</p><p><b>METHODS</b>hIGF-1cDNA was amplified in vitro from normal human liver cells by using RT-PCR and cloned into plasmid vector pLgXSN. The recombinant vector pLghIGF-1SN and control vector pLgGFPSN were transfected into packaging cell PT67 and G418 was used to select positive colony. Myoblasts were infected with a high titre viral supernatant and transduction efficiency was evaluated as GFP expression. The expression of hIGF-1 mRNA in myoblasts was investigated by immunocytochemistry and RT-PCR. MTT assays detected the growth of myoblasts in vitro. Myoblasts transduced with pLghIGF-1SN were injected into hind limb muscles of 10 - 12 week male SD rats. Formed tissues were harvested 4 weeks later. Myocyte diameter, mean weight of hind limb and body were measured to evaluate the skeletal muscle growth.</p><p><b>RESULTS</b>Recombinant retroviral plasmid vector pLghIGF-1SN was constructed successfully. The titre of the packaged recombinant retrovirus was 1 x 10(6) cfu/ml. The transfection rate of PT67 cells reached 100% after G418 screening. hIGF-1 expression was positive in myoblast-IGF-1. The proliferation rate of myoblast-IGF-1 in vitro was higher than GFP-myoblast or myoblast (P < 0.05). The mean weights of hind limb and body of rats injected myoblast-IGF-1 were higher than those of the rats injected with myoblast-GFP or myoblast (P < 0.05). Myocyte diameter had a significant increase in IGF-1 group compared to GFP group and myoblast group (P < 0.05).</p><p><b>CONCLUSIONS</b>The transfection of the human IGF-1 gene mediated by a retroviral vector can promote the growth of skeletal muscle in rats. Genetically modified primary skeletal myoblasts provide a possibly effective approach to treat some skeletal muscle diseases.</p>
Subject(s)
Animals , Rats , Cells, Cultured , DNA, Recombinant , Genetics , Genetic Vectors , Insulin-Like Growth Factor I , Genetics , Physiology , Muscle, Skeletal , Myoblasts , Physiology , Rats, Sprague-Dawley , Retroviridae , Genetics , TransfectionABSTRACT
The aim of this study is to construct a lentiviral vector encoding human growth hormone, and to achieve the long, efficient and stable expression in murine skeletal myoblasts. Primary skeletal myoblasts were isolated from Sprague-Dawley rats and cultured by enzymatic digestion. We tested them by Desmin immunohistochemistry stains and found their viability was up to 94% by Trypan blue. Human growth hormone (hGH) cDNA was subcloned into expression vector pLenti6/V5-D-TOPO to construct recombinant pLenti6/V5-hGH. The pLenti6/V5-hGH and the contructed pLenti6/V5-EGFP were transfected into murine skeletal myoblasts by the Lipofectamin 2000. Through counting by the Confocal Laser Scanning Microscope, we identified the transfection efficency. We added the blasticidin to the 6-well plate with lids and obtained stable myoblasts expressing hGH. The concentration of human growth hormone (hGH) in cell culture medium was detected by Radioimmunoassay (RIA). Polymerase Chain Reaction (PCR) and DNA sequence showed hGH cDNA had been correctly inserted into pLenti6/V5-D-TOPO vector. Bright green fluorescence of the transfected cells could be observed under the Confocal Laser Scanning Microscope after 24 h transfection with pLenti6/V5-EGFP plasmids, and the transfection rate reached 40%. The difference was distinct (P < 0.01) between the pLenti6/V5- hGH groups and control groups in the secretive level of human growth hormone. After 8 weeks, the expression of human growth hormone was still stable. Then, we validated the biological characterization of the rhGH by the enzyme-link immunosorbent assay (ELISA) of the Insulin-like growth factor I (IGF-1). These results demonstrate we have successfully constructed the recombinant pLenti6/V5-hGH plasmids and accomplished rhGH long, efficient and stable expression ectopic in skeletal muscle myoblasts.