1.Hair Lead Level of Children Living in Lead Polluted Area
Ping XIE ; Chong TENG ; Xiaodong LI
Journal of Environment and Health 1992;0(04):-
Objective To understand the environmental lead pollution status in Tongzhou and the biological burden of lead in children living in the lead polluted area.Methods The 353 pupils aged 7-14 years were randomly selected in Zhangzhishan town central elementary school that was near to steel wire factories,283 pupils were selected as the control by using the same methods in an elementary school around where there is no any steel wire factory.Every students were investigated by questionnaires,meanwhile their hair were collected to determine lead with ASS method.Results In the polluted area group,hair lead of 77 pupils exceeded the normal level,the median was 4.437 ?g/g,the rate of exceeding the normal level(≤10 ?g/g)was 21.81%,and 65 pupils with lead poisoning related symptoms(18.41%).In the control group,the median was 3.965 ?g/g,the rate of exceeding the normal level was 11.31%,38 pupil with lead poisoning related symptoms(13.43%).After controlled the passive smoking confounder,the difference of hair lead level between these two groups was still significant(P
2.Effect of iodine supplement on thyroid of iodine-deficient rats
Wei CHONG ; Di TENG ; Xiaoguang SHI
Chinese Journal of Practical Internal Medicine 2002;0(08):-
Objective To study the effect of chronic iodine supplement on thyroid of iodine-deficient rats.Methods Iodine-deficient rat models were made by giving 4- week-old rats iodine-deficient fodder for 3 months.These iodine-deficient rats were then supplemented for 8 months 1-,3- and 6- fold iodine which corresponded to the 3 levels of iodine intake found in our epidemiological study in 3 rural communities.Then changes of thyroid after iodine supplement were observed.Results After supplement of 1-,3- and 6- fold iodine to iodine-deficient rats for 8 months,thyroid relative weight did not recover,and iodine accumulated in thyroid.The ultrastructure injuries of swelling mitochondria and dilating endoplasmic reticulum in epithelial cells of iodine-deficient thyroid did not recover,but became worse with iodine supplement increase.Conclusion Iodine supplement alone can not correct the injuries resulting from iodine deficiency;moreover,a sub-pathological state might occur.
3.Chronic effects of excessive iodine intake on apoptosis of thyrocytes in Wistar rats
Wei CHEN ; Xiaochun TENG ; Zhongyan SHAN ; Chenling FAN ; Haixia GUAN ; Na MAN ; Yushu LI ; Yafie TONG ; Wei CHONG ; Weiping TENG
Chinese Journal of Endocrinology and Metabolism 2008;24(6):649-653
Objective To explore the chronic effects of mild and moderate iodine excess and iodine restriction on apoptosis of thyrocytes. Methods Wistar rats were exposed to 4 different doses of iodine: 4 μg/d (control), 6 μg/d (1.5 fold iodine excess), 12 μg/d (3 fold iodine excess), and 24 μg/d (6 fold iodine excess) for 1, 2, 4 and 8 months. Some rats treated for 8 months were fed with 4 μg/d iodine for another 3 months. Urinary iodine concentration was monitored by arscnic/cerium catalyzing spectrophotography. Apoptosis was determined by flow cytometry after Annexin V-FTTC staining and uhrastructure assessment under electronic microscope. Cell cycle kinetics was analyzed by flow eytometry after propidium iodine staining. Fluorescent measurement by DCFH-DA probe was used to determine the intracellular reactive oxygen species (ROS) level. Expressions of apoptic proteins were analyzed by flow cytometry and immunohistochemistry. Results Apoptotosis rate and ROS production in thyrocytes were significantly increased in 3 and 6 fold iodine excess groups after 4 months and 8 months (all P < 0.05), which was reversed with iodine restriction. 6 fold iodine exposure was proved to cause a reduction of cells in GOG1-phase (64% and 67% vs 80%, both P < 0. 05) and a concomitant accumulation in S-phase (5% and 6% vs 3%, both P <0.05) after 4 months and 8 months. Expressions of Fas, FasL and TRAIL proteins in 3 and 6 fold iodine excess groups after 8 months were increased by 2 to 4 times compared with control group and did not return to normal after iodine restriction. Bcl-2 and Bax remained constant. Positive correlations were observed among iodine amount, apoptosis rate and ROS level in 6 fold iodine excess group after 8 months (r = 0. 637-0.790, P < 0.01). Conclusion Chronic iodine excess results in thyrocyte apoptosis due probably to generation of ROS.
4.Cloning, Sequencing of Suaeda heteroptera kitag CMO cDNA and Construction of its Recombinant Plant Expression Vector
Chong-Bin ZHONG ; Chang-Jiang LIU ; Teng FEI ; Xiao-Dong YUAN ; Li-Hui SUN ;
China Biotechnology 2006;0(07):-
Total RNA was extracted from leaf of Suaeda hetroptera kitag, then the CMO ( choline monooxygenase) cDNA was amplified using the reverse transcriptase polymerase chain reaction ( RT-PCR) method and cloned into pMD-T-simple vector. The positive clones from the Blue/White Screen were sequenced. After confirming its validity, the CMO gene fragment was cloned into pBI121 vector. Double enzyme restriction and PCR analysis indicated that the pBI121/CMO recombinant plasmid was successfully constructed.
5.The changes of thyrotropin level in euthyroid population:a 5-year follow-up study in communities with different iodine intakes
Haixia GUAN ; Yanyan CHEN ; Zhongyan SHAN ; Xiaochun TENG ; Di TENG ; Yushu LI ; Xiaohui YU ; Chenling FAN ; Wei CHONG ; Fan YANG ; Hong DAI ; Yang YU ; Jia LI ; Dong ZHAO ; Jinyuan MAO ; Weiping TENG
Chinese Journal of Internal Medicine 2009;48(4):308-311
Objective To determine the factors that influence the development of abnormal thyrotropin (TSH) level in an euthyroid population.Methods We conducted a follow-up study in 3 communities with different iodine status.Of the 3403 euthyroid subjects at baseline screened in 1999,80.1% ( n = 2727 ) was visited and sampled in 2004 for measuring TSH,thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb).Results Iodine status in the 3 communities were stable.Decreased TSH level( <0.3 mU/L) developed in 2.5% (n =68) of sampled subjects,while raised TSH level( > 4.8 mU/L) in 2.4% (n = 64).A logistic analysis showed that risk factors for developing decreased TSH level included positive conversion of TPOAb (OR = 5.5 ),positive TPOAb both in 1999 and in 2004 ( OR = 4.0),positive TgAb in 2004 ( OR = 3.7) and TSH < 1.0 mU/L in 1999 ( OR = 2.6).Risk factors involved in developing raised TSH level included iodine status of Zhangwu community ( OR = 4.1 ),iodine status of Huanghua community ( OR = 3.9),positive TgAb in 2004 ( OR = 3.7 ),positive TPOAb both in 1999 and 2004 (OR =3.6),positive conversion of TPOAb (OR =2.7) and TSH > 1.9 mU/L in 1999 (OR = 2.6 ).Conclusions Exposure to long-term iodine excess imposes danger of developing hypothyroidism.The risk will be even higher when exposing to iodine adequacy after correction of iodine deficiency.An interval between 1.0 and 1.9 mU/L of TSH level was optimul with the least probability of developing abnormal TSH level.
6.Mutiple-slice spiral CT diagnosis of atypical intraabdominal hernia.
Li-min ZHANG ; Chong-quan HUANG ; Chen-di TENG ; Chong-lin TAO
Chinese Journal of Gastrointestinal Surgery 2011;14(11):871-874
OBJECTIVETo discuss the value of multiple-slice spiral CT diagnosis of atypical intraabdominal hernia.
METHODSThe clinical and CT findings of 16 cases of atypical intraabdominal hernia confirmed surgically were retrospectively analysed.
RESULTSIn all the 16 cases, the contents of hernia were small bowels and the mesentery. Nine cases were caused by the adhesion after abdominal operations or infection, 6 by the mesenteric foramen, and 1 by the gap of pelvic peritoneum. The main CT findings were as follows:(1)the obstructed small bowels gathered abnormally and showed cluster shape(9 cases); the walls of the bowels thickened with edema and showed "target" sign with exudate in the neighboring spaces(5 cases); other part of the abdominal cavity became empty for lack of small bowels(4 cases).(2) Abnormal arrangement of the branches of mesenteric vessel, which appeared gathered or pulled or rigid and displacement of the main branches to left or right(12 cases). Thickened mesenteric vessel (4 cases): torsion of mesentery with "whirlpool" sign (3 cases). (3) With the help of multiplanar reformation, 5 cases showed the evidence of hernia rings. In the ring area, there were gathered or pulled or rigid and radiating mesenteric vessel and the dilated or effusion bowels in cluster arrangement forming "parachute" and "bundle of balloons" sign.
CONCLUSIONCT manifestations of atypical intraabdominal hernia has some specific characteristics, which is of important value for clinical diagnosis and treatment.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Hernia, Ventral ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Tomography, Spiral Computed ; methods ; Young Adult
7.Hearing Loss amongst the Elderly in a Southeast Asian Population - A Community-based Study.
Jek Chong LEE ; Adrian Noel DANKER ; Yu Han WONG ; Ming Yann LIM
Annals of the Academy of Medicine, Singapore 2017;46(4):145-154
INTRODUCTIONThe aim of this study was to determine the prevalence of hearing loss amongst the elderly population attending community services in Singapore. The usefulness of the Hearing Handicap Inventory for the Elderly Screening version (HHIE-S) in detecting hearing loss was also investigated.
MATERIALS AND METHODSPure-tone audiometry was carried out on a randomly recruited cohort of people (n = 338) over 60 years old and who were attending rehabilitation and social day care services for senior citizens at St Luke's Elder Care centres located throughout the city. Prior to the hearing test, subjects were administered the HHIE-S questionnaire, which was translated into the language they were most conversant in.
RESULTSThe study cohort showed mean pure-tone average at speech frequencies (0.5, 1, 2 and 4 kHz; 4-frequency average hearing level [4FA HL]) of the subjects' better hearing ear that has worsened with age. The percentage of the elderly with disabling hearing impairment (4FA >40 dB HL) was 9.1% (60 to 69 years old), 22.0% (70 to 79 years old), 35.7% (80 years old and above). Across all age groups, males had significantly poorer thresholds at 4 kHz than females. When adjusted for the demographic profile of the country, the prevalence of hearing loss (4FA >25 dB HL) and disabling hearing impairment (4FA >40 dB HL) amongst the elderly in Singapore was 63.7% and 16.2%, respectively. We estimate that there are currently 422,000 elderly with hearing loss greater than 25dB HL and over 100,000 elderly with disabling hearing loss of over 40 dB HL. Of subjects with a disabling hearing impairment, only 7.5% used hearing aids. The use of self-reporting HHIE-S showed poor sensitivity in detecting hearing loss of various severities amongst the elderly.
CONCLUSIONThese data provide estimates of the prevalence and severity of hearing loss in older persons in Singapore and suggest that more can be done to help the elderly recognise, acknowledge and address hearing loss in the country.
8.Multivariate analysis of relationships between iodine biological exposure and subclinical thyroid dysfunctions.
Wei CHONG ; Zhong-Yan SHAN ; Wei SUN ; Wei-Ping TENG
Chinese Medical Sciences Journal 2005;20(3):202-205
OBJECTIVETo assess the relationships between iodine biological exposure and subclinical thyroid dysfunctions.
METHODSThe cross-sectional survey was performed to obtain the epidemiologic data of population in three communities with different iodine biological exposure: mild iodine deficiency [median urinary iodine concentration (MUI) of 50-99 microg/L], more than adequate iodine intake (MUI of 200-299 microg/L), and excessive iodine intake (MUI over 300 microg/L). Univariate and multivariate analysis (logistic regression analysis) were used to analyze the risk factors of subclinical hypothyroidism and subclinical hyperthyroidism.
RESULTSLogistic regression analysis with sex and age controlled suggested that more than adequate iodine intake (OR = 3.172, P = 0.0004) and excessive iodine intake (OR = 6.391, P = 0.0001) increased the risk of subclinical hypothyroidism, while excessive iodine intake decreased the risk of subclinical hyperthyroidism (OR = 0.218, P = 0.0001). Logistic regression analysis including interaction of iodine intake and antibodies [thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb)] suggested that excessive iodine intake was an independent risk factor of subclinical hypothyroidism (OR = 6.360, P = 0.0001), but independent protect factor of subclinical hyperthyroidism (OR = 0.193, P = 0.0001). More than adequate iodine intake and it's interaction with TgAb increased the risk of subclinical hypothyroidism independently, in addition, it decreased the risk of subclinical hyperthyroidism at the present of TPOAb.
CONCLUSIONBoth excessive iodine intake and more than adequate iodine intake could increase risk of subclinical hypothyroidism, supplement of iodine should be controlled to ensure MUI within the safe range.
Adult ; Autoantibodies ; blood ; China ; Cross-Sectional Studies ; Dose-Response Relationship, Drug ; Female ; Humans ; Hyperthyroidism ; chemically induced ; epidemiology ; metabolism ; Hypothyroidism ; chemically induced ; epidemiology ; metabolism ; Iodide Peroxidase ; immunology ; Iodine ; administration & dosage ; adverse effects ; urine ; Male ; Multivariate Analysis ; Risk Factors ; Surveys and Questionnaires ; Thyroglobulin ; immunology
9.Usage of glucometer is associated with improved glycaemic control in type 2 diabetes mellitus patients in Malaysian public primary care clinics: an open-label, randomised controlled trial.
Mastura ISMAIL ; Cheong-Lieng TENG ; Chong-Lieng TENG ; Mimi OMAR ; Bee Kiau HO ; Zainab KUSIAR ; Ruziaton HASIM
Singapore medical journal 2013;54(7):391-395
INTRODUCTIONSelf-monitoring of blood glucose (SMBG) has been underutilised. We conducted an open-label, randomised controlled trial to assess the feasibility of introducing SMBG in primary care clinics in Malaysia.
METHODSThis was an open-label, randomised controlled trial conducted in five public primary care clinics in Malaysia. Patients with type 2 diabetes mellitus (age range 35-65 years) not performing SMBG at the time of the study were randomised to receive either a glucometer for SMBG or usual care. Both groups of patients received similar diabetes care from the clinics.
RESULTSA total of 105 patients with type 2 diabetes mellitus were enrolled. Of these, 58 and 47 were randomised to intervention and control groups, respectively. After six months, the glycated haemoglobin (HbA1c) level in the intervention group showed a statistically significant improvement of 1.3% (p = 0.001; 95% confidence interval 0.6-2.0), relative to the control group that underwent usual care. The percentages of patients that reached the HbA1c treatment target of ≤ 7% were 14.0% and 32.1% in the control and intervention groups (p = 0.036), respectively.
CONCLUSIONThe usage of a glucometer improved glycaemic control, possibly due to the encouragement of greater self-care in the intervention group.
Adult ; Aged ; Blood Glucose Self-Monitoring ; Diabetes Mellitus, Type 2 ; blood ; Female ; Glycated Hemoglobin A ; analysis ; Humans ; Malaysia ; Male ; Middle Aged ; Primary Health Care
10.Recent advances of MDM2-p53 inhibitors
Ji-chao WANG ; Cai-bin YANG ; Yi-lin ZHUO ; Chong LIANG ; Jun-gang WANG ; Sheng DONG ; Bo-teng LI ; Shu-hua ZHANG ; Guo-gang ZHANG
Acta Pharmaceutica Sinica 2021;56(4):983-995
Protein-protein interactions (PPI) are involved in a variety of biological processes, including cell-to-cell interactions, metabolism and development control. The misregulation, post-translational modification and interference of PPI are related to a variety of human diseases, making the regulation of these interactions a very attractive field of drug discovery. In recent years, the interaction between MDM2 and p53 has become a research hotspot, which plays an important role in the treatment of tumors. But unfortunately there are no such inhibitors approved all over the world. In this view, recent advances of MDM2-p53 inhibitors were briefly described and its inhibitors with potential therapeutic activities in clinical studies were introduced.