The effect of initial substrate concentration on the growth,metabolic activities of Photosynthetic bacteria (PSB) in the process of hydrogen production is studied.The empirical relation of the initial substrate concentration to the specific growth rate,specific substrate consumption rate and specific hydrogen production rate of PSB are developed based on the modified Monod model.It is found that the results given by the model are well agreed with the experimental data in growth phase and stationary phase of PSB.Meanwhile,the optimal substrate concentration in the process of growth,metabolism and hydrogen production is 50 mmol/L.Furthermore,when the initial substrate concentration deviates 50 mmol/L,the activation of PSB is limited or inhibited,and the inhibiting effect is more prominent than the limiting effect.In addition,it is demonstrated that initial substrate concentration has little effect on the specific substrate consumption rate.

Objective To investigate the iodine nutritional status of targeted population in the high-risk areas of iodine deficiency disorders in Chongqing, so as to provide scientific evidence for establishing prevention and remedial measures. Methods Six towns were selected in Chengkou and Wuxi Counties to found suspected dementia patients born after first Jan, 1997. Two hundred children aged 8-10 years were investigated in every town. The thyroid volume, intelligence quotient(IQ) and urinary iodine of the children were examined. Forty women (pregnant and nursing women) were investigated in every town. The iodine content of salt from their home was measured. The thyroid volume was examined by palpation and B-uhrasound. IQ was measured by combined Raven Test in China(CRT-RC2). Urinary iodine was determined using the acid digest arsenic-cerium contacting method, and iodined salt was detected using direct titration method. Results Six suspected dementia patients were found in the local town hospital. Five eases were excluded. There was 1 case born in other place. The rates of goiter by palpation and B-ultrasound were 9.58%(92/960) and 8.89%(65/731), respectively. The median of urinary iodine of children and women was 319.15 μg/L and 248.42 μg/L, respectively. The mean of IQ of the children was 103.32. The coverage rate of iodine salt from residents was 98.82%(336/340). Conclusions The iodine nutrition of children was good and there is no newly occurred cretinism in Chengkou and Wuxi Counties. Goiter rate and median of urinary iodine aged 8-10 years and of women, coverage rate of iodine salt from resident has meet the standard set for basical elimination iodine deficiency disorders.

Objective To undemtand the rhythm of urinary iodine level of children aged 8-10 in Chongqing city.Methods In April 2008,using the stratified random sampling method,we sampled 60 children aged 8-10 in a lodging primary school in Chongqing(20 per age group,half male and half female),the urine samples were collected in the morning and at 10:00,12:30,16:00,iodine in urine was detected by method of Ce and arsenic catalytic speetrophotometry(WS/T 107-2006).The difference of the urinary iodine level was compared by age,sex and time of day.Results The median urinary iodine of 60 children was 265.07μg/L on the overall.Irrespective of the stratification factors,excluding morning urinary iodine(366.75μg/L)and urinary iodine at 10:00(338.30 μg/L),the urinary iodine between 12:30(235.15μg/L)and 16:00(251.50μg/L)was not significant(all P>0.05),statistically significant differences(all P<0.05)were found between any two.The urinary iodine of 8-year-old group at different times of the day was significantly different(all P<0.05),except between morning urinary iodine (298.90 μg/L)and at 10:00,16:00(279.00,286.59 μg/L),between urinary iodine at 10:00 and 16:00(all P>0.05).The 9-year-old group's urinary iodine were not significantly different between morning urine(366.15μg/L)and 10:00(368.10 μg/L),and between 12:30(244.00 μg/L)and 16:00(186.30 μg/L,all P>0.05),significant differences were faund at other times of the day(all P<0.05).The 10-year-old group of urinary iodine changed very little before 12:30 (382.85,449.60,337.00 μg/L, all P > 0.05 ), followed by rapid decline to 16: 00 (269.35 μg/L), and compared with the morning urine and 10:00, there was significant difference(all P < 0.05).Regardless boys or girls, the urinary iodine at different times qf the day was significantly different (all P < 0.05),except between morning urinary iodine(337.32,309.28 μg/L) and at 10:00(316.15,288.27 μg/L), between urinary iodine at 12:30(251.18,211.45 μg/L) and 16:00(235.02,211.45 μg/L, all P > 0.05). Conclusions The change of urinary iodine level in children aged 8 - 10 was not obvious before noon, changes can be seen in the afternoon.Urinary iodine level before 10:00 is indicative.

Objective To improve the recognition of nervous system symptoms of inborn errors.Methods Five patients with organic acidemias were screened by urine organic acid analysis(gas chromotography-mass spectrometry,GC/MS),3 cases of methylmalolic acidemias(MMA) and 2 cases of propionic acidemias(PA) were confirmed.They were treated with special diet and medicine after diagnosis.Result The improvement of mental development was observed after treatment.Conclusions Most of organic acidemias involve nervous systems,causing non-specific symptoms of nervous system as lethergy,seizures,mental retardation.Inborn errors of metabolism shall be kept in mind when causes of the symtoms of acidosis,seisures,mental retardation and lethergy are investigated.GC/MS is a very important method in diagnosis of organic acidemias.Early diagnosis and early treatment can improve the mental prognosis.

A in vitro platelet aggregation bioassay was developed for the quality control of XST capsules. The in vitro anti-platelet aggregation effect in rats was observed to detect the bioactivity of XST capsules. Panax notoginseng saponins and Xuesaitong lyophilizedpowder for injection were taken as standard control substances to determine the potency. According to the results, XST capsules showeda significant inhibitory effect on thrombin-induced platelet aggregation in a dose-dependent manner. The in vitro anti-platelet activity oflyophilized powder for injection was stabler than that of Panax notoginseng saponins, and so suitable to serve as a standard control substance. The biological potency of XST capsules compared with standard control substance was detected by using parallel line assay. According to the results, the established bioassay method had a good repeatability (RSD 2.92%). The sample test results could pass thereliability test(linear deviation P > 0.05, parallel deviation P > 0.05). This bioassay method could be used as one of the complementary quality control methods for XST capsules.
Animals ; Capsules ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Male ; Panax notoginseng ; chemistry ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Saponins ; pharmacology

OBJECTIVETo evaluate the impact of nicotine- and tar-free cigarette smoke extract (fCSE) on the serum testosterone (T) level and erectile function of male rats.

METHODSWe randomized 30 male SD rats to three groups of equal number to receive subcutaneous injection of PBS (1.0 ml / 300 g body weight per day), fCSE (1.0 ml/300 g body weight per day), and reduced glutathione hormone (GSH, 200 mg per kg body weight per day) in addition to fCSE (fCSE + GSH), respectively, all for 8 weeks. Then we evaluated the erectile function of the rats by measuring the maximal intracavernous pressure (MICP), mean arterial pressure (MAP), ICP/MAP ratio, time of stimulation to MICP (Tmax), and cavernosal filling fate (CFR). We determined the serum T level, the activities of superoxide dismutase (SOD) , malondialdehyde (MDA), and nitric oxide synthase (NOS) in the cavernosal tissue, and also observed the morphological changes of the corpus cavernosum.

RESULTSCompared with the controls, the rats of the fCSE group showed obvious decreases in the levels of serum T ([5.37 ± 1.43] vs [3.22 ± 1.11] μg/L), NOS ([2.90 ± 0.27] vs [1.67 ± 0.18] U/mg) , and SOD ([18.41 ± 1.09] vs [13.36 ± 1.18] U/mg prot) and erectile function-related indexes MICP ([85.92 ± 6.36] vs [58.99 ± 10.76] mmHg), MICP/MAP (0.86 ± 0.09 vs [0.56 ± 0.08]), and CFR (2.14 ± 0.44 vs 0.89 ± 0.44), but markedly increased Tmax ([29.90 ± 5.78] vs [42.90 ± 8.56]s), with a positive correlation between the serum T level and CFR (r = 0. 364, P < 0.05). Masson staining revealed a lower ratio of the corpus cavernosum smooth muscle tissue to collagen fiber in the fCSE group (0.27 ± 0.04) than in the control (0.98 ± 0.12). Compared with the fCSE group, the fCSE + GSH group exhibited significantly improved MICP ([58.99 ± 10.76 ] vs [77.95 ± 7.71] mmHg), MICP/MAP (0.56 ± 0.08 vs 0.77 ± 0.09), and CFR (0.89 ± 0.44] vs 1.76 ± 0.42) and shortened Tmax ([42.90 ± 8.56 ] vs [32.10 ± 5.84 ] s). The ratio of the corpus cavernosum smooth muscle tissue to collagen fiber was higher in the fCSE + GSH than in the fCSE group (0.77 ± 0.09 vs 0.27 ± 0.04) but still lower than in the control (0.98 ± 0.12).

CONCLUSIONNicotine- and tar-free cigarette smoke extract reduces the serum T level and erectile function of rats, which is related to oxidative stress. Antioxidant therapy can improve erectile function but has a limited value for morphological protection of the penile tissue.

Animals ; Erectile Dysfunction ; chemically induced ; Male ; Malondialdehyde ; metabolism ; Muscle, Smooth ; pathology ; Nicotine ; Nitric Oxide Synthase ; metabolism ; Penile Erection ; drug effects ; Penis ; pathology ; Rats ; Rats, Sprague-Dawley ; Smoke ; adverse effects ; Superoxide Dismutase ; metabolism ; Tars ; Tobacco ; adverse effects

Child, Preschool ; Diagnosis, Differential ; Female ; Humans ; Rickets ; diagnosis ; etiology ; therapy ; Treatment Outcome ; Vitamin D Deficiency ; complications

Objective To determine the urinary iodine level of people in Yunyang and Bishan County of Chongqing and explore into its influencing factors. Methods Using multistage cluster stratified simple random sample method, Yunyang and Bishan County were chosen as research spots, then thirty children aged 8-10 in each 3 primary school of the 2 counties were selected using stratified randomization sampling method to inspected their urine and household salt for iodine and the iodine content in drinking water. Results Five hundred and seventy-one urine samples were inspected and the urinary iodine median was 261.47 μg/L. 5.78% (33/571) and 37.48%(214/571) of samples had an urinary iodine median less than 100 μg/L and more than 300 μg/L. The urinary iodine median of Yunyang County was higher than that of Bishan (H = 7.42, P < 0.01). The iodine salt coverage rate, the qualified rate and edible qualified iodine salt rate respectively were 99.64%(554/556), 94.22% (522/554) and 93.88% (522/556) in 556 samples of family table salt. Eighty-seven samples of drinking water were inspected, resulting an averaged iodine content of 8.81 and 2.97 μg/L, respectively in the 2 counties. Conclusions The 2 counties are all the area of iodine deficiency. The urinary iodine level, although meeting the demand of eliminating iodine deficiency diseases, is a little bit higher given that iodized salt of present doage has been taken for a long time. The content of iodized salt should be adjusted accordingly.

Objective To investigate iodine deficiency disorders(IDD) in Chongqing and Linzhi, and to provide scientific basis for IDD control and prevention. Methods According to the national program developed in 2007, investigation was conducted in Chengkou and Wuxi county in Chongqing municipality, and Linzhi, Bomi,Milin and Langxian county in Linzhi prefecture. Five towns were sampled in Linzhi county, and 3 in other counties.In each town, one township primary school and two village primary schools were selected to inspect thyroid by B ultrasound and palpation, and urinary iodine of children aged 8 to 10 years was tested in these schools. Meanwhile,2 villages were selected in each town for test of salt iodine level and urinary iodine of childbearing age women and search cretin cases. Results Three hundred and forty families in Chongqing and 915 families in Linzhi were investigated. The coverage of iodized salt in Chongqing was 98.82%(336/340), which was significantly higher than that in Linzhi[66.34%(607/905), x2 = 139.56, P ＜ 0.01]. Goiter rate of children in Chongqing was 9.27%(89/960) by palpation and 8.34% (61/731) by B ultrasound, while goiter rate of children in Linzhi was 7.80%(102/1308) by palpation and 5.53% (69/1248) by B ultrasound. The difference of goiter rate by palpation between Chongqing and Linzhi was not statistically significant (x2 = 1.37, P ＞ 0.05 ). But goiter rate of children by B ultrasound in Chongqing was higher than that in Linzhi (x2= 5.51, P ＜ 0.05). In Chongqing, the median urinary iodine was 319.15 μg/L, and 345.75 μg/L in Chengkou county and 281.39 μg/L in Wuxi county. In Linzhi prefecture, the median urinary iodine was 189.81 μg/L, and 207.81 μg/L in Linzhi county, 161.12 μg/L in Bomi county, 131.83 μg/L in Milin county and 334.60 μg/L in Langxian county. The median urinary iodine in childbearing women were 248.42 μg/L in Chongqing and 121.25 μg/L in Linzhi. The median urinary iodine in Chongqing both in children and women were higher than those in Linzhi. No new cretin case was found in these two areas. Conclusions Goiter rate in high risk areas of IDD in Chongqing and Linzhi has decreased to less than 10%.No new cretin case is found in these areas. It can be concluded that the work of control and prevention is effective.There is excess iodine in Chongqing. In Linzhi county and Langxian county, iodine is excess in children and deficient in women. Further investigation should be conducted to find out the reason. Population iodine is excess in Bomi and Milin counties. The concentration of salt iodine should be decreased in Chongqing. In Linzhi prefecture,adding iodine measures should be adjusted based on further investigation.

Objective To understand distribution of the endemic fluorosis areas and running status of water-improving defuoridation projects in Gausu province. Methods In 2006, Gansu province endemic fluorosis areas, the content of fluoride in drinking water was measured in villages where water was not improved, running status of delluoridation projects was investigated and the content of fluoride in drinking water were determined in villages where water was improved. Dental fluorosis and skeletal fluorosis prevalence were examined in children in identified high-fluorlde villages. The fluorine content in drinking water was determined by F-ion selective electrode, dental fluorosis of children was diagnosed using Dean method, and adults skeletal fluorosis was diagnosed according to "National Standard for Clinical Diagnosis of Endemic Skeletal Fhiorosis" (GB 16396-1996). Results Water samples were examined in 1997 villages of 26 countries, among which water fluoride content was higher than 1.0 mg/L in 598 villages, accounting for 29.94%(598/1997). All 1215 water-improving and defluoridation projects had been investigated, among which 94.90%(1153/1215) of the projects were functioning well, and intermittent and abandoned projects accounted for 2.96%(36/1215) and 2.14%(26/1215). Mean fluoride of treated water of 1084 water-improving and defluoridation projects had water fluoride content ≤ 1.0 mg/L, accounted for 90.79%(1084/1194) ; mean fluoride of water from 1068 water-improving and defluoridation projects had water fuoride content ≤ 1.0 mg/L, accounting for 91.75%(1068/1164). Total 86 390 children of 8 to 12 year-old were examined, the detectable rate of dental fluorosis was 22.47%(19 414/86 390) and 142 211 adults above 16 year-old were examined, the detectable rate of skeletal fluorosis was 4.20%(5967/142 211). Conclusions Some villages yet have water fluoride content exceeding the standard. Some projects are abandoned and running badly, leading to fluoride content exceeding the standard. In a few areas, the prevalence of children dental fluorosis and adult skeletal fluorosis still exists in Gansu province, the task of prevention and control for endemic fluorosis is still arduous. We must raise the effect of prevention and treatment of this disease.