Search PubMed⌕ Search

Biomedical subjects

Hong Yan

Publications and source records attributed to Hong Yan.

At least 19 recordsLinked to original sources

Effects of early enteral arginine supplementation on resuscitation of severe burn patients.

OBJECTIVES: To investigate the effects of dietary supplementation of l-arginine (l-Arg) on shock in severely burned patients. METHODS: This was a prospective, randomized, single blind, controlled study. Forty-seven severely burned patients due to various causes with a total burn surface area (TBSA) more than 50% each admitted in early postburn phase (within 10h postburn) were included in this study. All patients were treated by the traditional resuscitation program of our institute. After the nasogastric feeding tube was placed, they were randomly divided into three groups-(1) group A400 (n = 16): giving gastrointestinal feeding with 500 ml 5% GNS, containing l-Arg (400 mg/ kgday) at equal pace with fluid resuscitation; (2) group A200 (n = 16): giving gastrointestinal feeding with 500 ml 5% GNS containing l-Arg (200 mg/ kgday); (3) group C (n = 15): giving gastrointestinal feeding with 500 ml 5% GNS without any supplementation. The feeding started within 12h after burn and lasted for 72 h, the feeding rate was controlled by an enteral feeding pump. The following parameters were observed on days (PBD) 1-4: serum nitric oxide content (NO), mean arterial blood pressure (MAP), oxygenation index (PO2/FiO2), and arterial blood content of lactic acid (LA). Gastric mucosal blood flow was measured by laser Doppler flow-metry on PBD1 and PBD2. RESULTS: (1) Enteral feeding of l-Arg did not change MAP of severely burned patients, with no difference in MAP between the l-Arg supplemented and control groups. (2) There were significant changes of the l-Arg supplemented groups (A400 and A200), with an increased gastric mucosa blood flow, oxygenation index, and a decreased LA content in arterial blood, compared with the control group. (3) The serous NO content was significantly decreased in the A400 group on PBD2-4 (P < 0.01), and in the A200 group on PBD4 (P < 0.05) compared with the control group. CONCLUSIONS: Enteral feeding with l-arginine supplementation on early stage of burn decreases NO production to a relatively normal level and exerts beneficial effects on the resuscitation of burned shock.

Adolescent↗

Subdimension-based similarity measure for DNA microarray data clustering.

Microarray data analysis is useful for understanding biological processes. A number of clustering algorithms have been used to achieve this task. However, the performance of these methods can be significantly degraded due to the presence of nonsignificant conditions. In this paper, we propose a robust clustering algorithm based on a similarity measure. The key concept of the proposed similarity measure is to measure the similarity between two data points by their subdimensions. For example, assume that x1, x2, and x3 are ten-dimensional data vectors. The data point x3 is said to be closer to x1 than x2 if more than half of the dimensions of x1 and x3 are closer to x1 than x2. Thus, if two patterns are very similar except for a small amount of features, this measure will preserve the similarity. We have performed eight experiments to test the robustness of the proposed method, including three synthetic data sets, three real world data sets, and two microarray data sets. We also have compared the proposed method with four different clustering algorithms. Experimental results show that the proposed method yields better results than existing clustering algorithms.

Algorithms↗

Thioredoxin, thioredoxin reductase, and alpha-crystallin revive inactivated glyceraldehyde 3-phosphate dehydrogenase in human aged and cataract lens extracts.

PURPOSE: To investigate whether mammalian thioredoxin (Trx) and thioredoxin reductase (TrxR), with or without alpha-crystallin can revive inactivated glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in both the cortex and nucleus of human aged clear and cataract lenses. METHODS: The lens cortex (including capsule-epithelium) and the nucleus were separated from human aged clear and cataract lenses (grade II and grade IV) with similar average age. The activity of GAPDH in the water-soluble fraction after incubation with or without Trx or/and TrxR for 60 min at 30 degrees C was measured spectrophotometrically. In addition, the effect of a combination of Trx/TrxR and bovine lens alpha-crystallin was investigated. RESULTS: GAPDH activity was lower in the nucleus of clear lenses than in the cortex, and considerably diminished in the cataractous lenses, particularly in the nucleus of cataract lenses grade IV. Trx and TrxR were able to revive the activity of GAPDH markedly in both the cortex and nucleus of the clear and cataract lenses. The percentage increase of activity in the cortex of the clear lenses was less than that of the nucleus in the presence of Trx and TrxR, whereas it was opposite in the cataract lenses. The revival of activity in both the cortex and nucleus from the cataract lenses grade II was higher than that of the grade IV. Moreover, Trx alone, but not TrxR, efficiently enhanced GAPDH activity. The combination of Trx and TrxR had greater effect than that of either alone. In addition, alpha(L)-crystallin enhanced the activity in the cortex of cataract grade II with Trx and TrxR present. However, it failed to provide a statistically significant increase of activity in the nucleus. CONCLUSIONS: This is the first evidence to show that mammalian Trx and TrxR are able to revive inactivated GAPDH in human aged clear and cataract lenses, and alpha-crystallin helped this effect. The inactivation of GAPDH during aging and cataract development must be caused in part by disulphide formation and in part by unfolding, and can be recovered by reducing agents and a molecular chaperone.

Adult↗

PromoterExplorer: an effective promoter identification method based on the AdaBoost algorithm.

MOTIVATION: Promoter prediction is important for the analysis of gene regulations. Although a number of promoter prediction algorithms have been reported in literature, significant improvement in prediction accuracy remains a challenge. In this paper, an effective promoter identification algorithm, which is called PromoterExplorer, is proposed. In our approach, we analyze the different roles of various features, that is, local distribution of pentamers, positional CpG island features and digitized DNA sequence, and then combine them to build a high-dimensional input vector. A cascade AdaBoost-based learning procedure is adopted to select the most 'informative' or 'discriminating' features to build a sequence of weak classifiers, which are combined to form a strong classifier so as to achieve a better performance. The cascade structure used for identification can also reduce the false positive. RESULTS: PromoterExplorer is tested based on large-scale DNA sequences from different databases, including the EPD, DBTSS, GenBank and human chromosome 22. Experimental results show that consistent and promising performance can be achieved.

Algorithms↗

Protective effect of aspirin against dexamethasone-induced cataract in cultured rat lens.

PURPOSE: To investigate the effect of aspirin on dexamethasone-induced cataract formation in cultured rat lenses. METHODS: One hundred and forty-eight lenses were divided into 3 groups and cultured in vitro: control (DMEM), cataract (DMEM + 10 microM dexamethasone), aspirin (DMEM + 10 muM dexamethasone + 2 mM aspirin). Following incubation, the transparency of the lenses was evaluated daily using a dissecting microscope. Twelve lenses from each group were homogenized and the activities of enzymes (catalase, superoxide dismutase and lactate dehydrogenase) from supernatants were measured after 1, 3, 5 and 7 days of incubation, respectively. The ultrastructure of lenses from the control and cataract groups was observed on the completion of 7-day incubation. RESULTS: Opacity was induced by dexamethasone in the nuclear region of the rat lenses. Lenses in the control group exhibited mist-like opacity and lenses in the cataract group showed dense nuclear opacity, whereas lenses in the aspirin-treated group only had a visible demarcation between nuclear and cortical regions at day 7. The activities of catalase, superoxide dismutase and lactate dehydrogenase in the cataract group decreased in a time-dependent manner. There was no significant loss of enzyme activities in either the control or the aspirin group throughout the incubation period. An orderly arrangement of fiber cells was noted, and the cell membrane, cell junction and organelles were normal in the control group. However, in the cataract group the arrangement of fiber cells was untidy and the lenses contained abnormal-appearing cells. The group exhibited swollen mitochondria, a large number of vacuoles and expanded extracellular lacunae. CONCLUSIONS: Dexamethasone induces nuclear cataract in the organ-cultured rat lens by chemically modifying proteins, including enzymes. The enzymes, including those that normally eliminate radial oxygen species, could be especially vulnerable. Aspirin significantly inhibits dexamethasone-induced cataract formation by inhibiting inactivation of those enzymes.

Animals↗

Mechanistic analysis of a DNA end processing pathway mediated by the Xenopus Werner syndrome protein.

The first step of homology-dependent repair of DNA double-strand breaks is the strand-specific processing of DNA ends to generate 3' single-strand tails. Despite its importance, the molecular mechanism underlying end processing is poorly understood in eukaryotic cells. We have taken a biochemical approach to investigate DNA end processing in nucleoplasmic extracts derived from the unfertilized eggs of Xenopus laevis. We found that double-strand DNA ends are specifically degraded in the 5' --> 3' direction in this system. The reaction consists of two steps: an ATP-dependent unwinding of double-strand ends and an ATP-independent 5' --> 3' degradation of single-strand tails. We also found that the Xenopus Werner syndrome protein, a member of the RecQ helicase family, plays an important role in DNA end processing. Mechanistically, Xenopus Werner syndrome protein (xWRN) is required for the unwinding of DNA ends but not for the degradation of single-strand tails. The xWRN-mediated end processing is remarkably similar to the end processing that has been proposed for the Escherichia coli RecQ helicase and RecJ single-strand nuclease, suggesting that this mechanism might be conserved in prokaryotes and eukaryotes.

Animals↗

The photopic negative response of the flash electroretinogram in retinal vein occlusion.

The photopic negative response (PhNR) has recently been shown to be severely affected in central retinal artery occlusion (CRAO), despite relative preservation of the cone b-wave compared to that in the healthy unaffected fellow eye. The aim of this study was to test how the PhNR of the flash electroretinogram (ERG) is affected in human retinal vein occlusion. PhNR was elicited with red stimuli (1 cd s/m2, 5 cd s/m2, and 7 cd s/m2 with 4 ms duration) and blue background (10 cd/m2). Standard Ganzfeld flash ERG was produced according to the ISCEV standard for the clinical electroretinogram (2004). Sixteen patients with central retinal vein occlusion (CRVO), 14 patients with branch retinal vein occlusion (BRVO), and 16 controls were analyzed. The amplitude of the PhNRs was significantly smaller in the CRVO and BRVO eyes than those in the unaffected fellow or control eyes (p = 0.000). There was a significantly greater reduction of PhNR amplitudes than that of other waves including the OPs, rod b-wave, combined a-wave and b-wave, cone a-wave and b-wave, and 30 Hz flicker ERG. Thus, PhNR amplitude in retinal vein occlusion is severely affected. There is a potential role for PhNR in assessing inner retinal damage and evaluating the effect of treatment.

Adult↗

Glutamine granule-supplemented enteral nutrition maintains immunological function in severely burned patients.

Glutamine is an important energy source for immune cells. It is a necessary nutrient for cell proliferation, and serves as specific fuel for lymphocytes, macrophages, and enterocytes when it is present in appropriate concentrations. The purpose of this clinical study was to observe the effects of enteral nutrition supplemented with glutamine granules on immunologic function in severely burned patients. Forty-eight severely burned patients (total burn surface area 30-75%, full thickness burn area 20-58%) who met the requirements of the protocol joined this double-blind randomized controlled clinical trail. Patients were randomly divided into two groups: burn control group (B group, 23 patients) and glutamine treated group (Gln group, 25 patients). There was isonitrogenous and isocaloric intake in both groups, Gln and B group patents were given glutamine granules or placebo (glycine) at 0.5 g/kgd for 14 days with oral feeding or tube feeding, respectively. The plasma level of glutamine and several indices of immunologic function including lymphocyte transformation ratio, neutrophil phagocytosis index (NPI), CD4/CD8 ratio, the content of immunoglobulin, complement C3, C4 and IL-2 levels were determined. Moreover, wound healing rate of burn area was observed and then hospital stay was recorded. The results showed significantly reduced plasma glutamine and damaged immunological function after severe burn Indices of cellular immunity function were remarkably decreased from normal controls. After taking glutamine granules for 14 days, plasma glutamine concentration was significantly higher in Gln group than that in B group (607.86+/-147.25 micromol/L versus 447.63+/-132.38 micromol/L, P<0.01). On the other hand, cellular immunity functions were improved in Gln group, such as lymphocyte transformation ratio, NPI, CD4/CD8 ratio and IL-2 compared those in the B group (P<0.05-0.01). However, for humoral immunity function such as the concentration of IgG, IgM, C3, C4, no marked changes were seen compared with the B group (P>0.05). In addition, wound healing was better and hospital stay days were reduced in Gln group (46.59+/-12.98 days versus 55.68+/-17.36 days, P<0.05). These indicated that immunological function damage is present after severe burn; supplemented glutamine granules with oral feeding or tube feeding abate the degree of immunosuppression, improve immunological function especially cellular immunity function, ameliorate wound healing and reduce hospital stay.

Adolescent↗

Carnosine inhibits modifications and decreased molecular chaperone activity of lens alpha-crystallin induced by ribose and fructose 6-phosphate.

PURPOSE: Alpha-crystallin, a major structural protein in the lens, prevents heat- and oxidative stress-induced aggregation of proteins and inactivation of enzymes by acting as a molecular chaperone. Modification of alpha-crystallin by some posttranslational modifications results in conformational changes and decreases in chaperone activity, which may contribute to cataractogenesis in vivo. Carnosine (beta-alanyl-L-histidine), an endogenous histidine dipeptide, prevents protein modifications including glycation and oxidation. The purpose of this study was to further explore whether carnosine can protect alpha-crystallin against glycation by a sugar and a sugar phosphate, and in particular to find whether it can protect against its decreased chaperone activity. Additionally, we investigated whether carnosine could directly react with a sugar and a sugar phosphate. METHODS: Bovine lens alphaL-crystallin was separated by size-exclusion chromatography on a Sephacryl S-300 HR column. alphaL-crystallin was incubated with different concentrations of fructose 6-phosphate (F6P) and ribose with or without carnosine for different times. The chaperone activity of alphaL-crystallin was monitored using the prevention of thermal aggregation of betaL-crystallin. The modified alphaL-crystallin was examined by SDS-PAGE and fluorescence measurements. The absorbance spectra of solutions of carnosine and sugars were investigated. RESULTS: Carnosine inhibited the crosslinking of alphaL-crystallin induced by F6P and ribose in a dose- and time-dependent manner. It protected alphaL-crystallin against its decreased chaperone activity induced by 100 mM F6P during four days incubation, but not against ribose-induced change. Control alphaL-crystallin gave 96% protection against aggregation of betaL-crystallin after four days incubation, but only 85% protection was achieved in the presence of F6P, rising to 96% (p=0.0004) in the presence of carnosine. After more extensive modification by sugar and a sugar phosphate, there was no significant protective effect of carnosine on alphaL-crystallin cross-linking or chaperone activity. The tryptophan fluorescence of modified alphaL-crystallin was remarkably decreased in the presence of F6P and ribose. However, the decrease was less when 50 mM carnosine was present during eight days incubation with F6P. Carnosine did not maintain the fluorescence when ribose was used. The nontryptophan fluorescence was increased with a shift to longer wavelengths in a time-dependent manner. Carnosine readily reacted with F6P and ribose thereby inhibiting glycation-mediated protein modification as revealed electrophoretically. The increased absorbance was time-dependent, suggesting adducts may be formed between F6P, ribose, and carnosine. CONCLUSIONS: This is the first report showing that carnosine can protect the chaperone activity of alpha-crystallin. This chaperone may protect against cataractous changes. In addition to demonstrating the effects of carnosine on prevention crosslinking, our studies also bring out important evidence that carnosine reacts with F6P and ribose, which suggests carnosine's potential as a possible nontoxic modulator of diabetic complications.

Animals↗

Microarray missing data imputation based on a set theoretic framework and biological knowledge.

Gene expressions measured using microarrays usually suffer from the missing value problem. However, in many data analysis methods, a complete data matrix is required. Although existing missing value imputation algorithms have shown good performance to deal with missing values, they also have their limitations. For example, some algorithms have good performance only when strong local correlation exists in data while some provide the best estimate when data is dominated by global structure. In addition, these algorithms do not take into account any biological constraint in their imputation. In this paper, we propose a set theoretic framework based on projection onto convex sets (POCS) for missing data imputation. POCS allows us to incorporate different types of a priori knowledge about missing values into the estimation process. The main idea of POCS is to formulate every piece of prior knowledge into a corresponding convex set and then use a convergence-guaranteed iterative procedure to obtain a solution in the intersection of all these sets. In this work, we design several convex sets, taking into consideration the biological characteristic of the data: the first set mainly exploit the local correlation structure among genes in microarray data, while the second set captures the global correlation structure among arrays. The third set (actually a series of sets) exploits the biological phenomenon of synchronization loss in microarray experiments. In cyclic systems, synchronization loss is a common phenomenon and we construct a series of sets based on this phenomenon for our POCS imputation algorithm. Experiments show that our algorithm can achieve a significant reduction of error compared to the KNNimpute, SVDimpute and LSimpute methods.

Algorithms↗

Inhibitive effect of genistein on hypoxia-induced basic fibroblast growth factor expression in human retinal pigment epithelium cells.

AIM: The time course changes of basic fibroblast growth factor (bFGF) expression induced by hypoxia and the effects of genistein on hypoxia-induced bFGF expression in the human retinal pigment epithelium (RPE) cells were studied. METHODS: The bFGF mRNA expression was examined by reverse transcription polymerase chain reaction. The bFGF protein expression was detected by Western blot. RESULTS: Hypoxia significantly increased bFGF mRNA expression. The maximal level detected at 24 h was approximately two times that at the start of treatment. With pretreatment of genistein (10, 20, 50, 100, and 200 microM) for 30 min, the elevated expression of bFGF mRNA was suppressed in a concentration-dependent manner. bFGF mRNA expression was reduced to 30.4% by 200 microM of genistein when compared with that untreated with genistein. Hypoxia treatment also remarkably increased the expression of bFGF protein. At 24 h after hypoxia, when the highest expression of bFGF protein was observed, it was approximately two times as much as that at the start of treatment. Genistein (10, 20, 50, 100, and 200 microM) could also suppress bFGF protein expression in a concentration-dependent manner. The highest suppression was observed when exposed to 200 microM of genistein, which was 43% of control. CONCLUSIONS: These results suggested that suppression of bFGF expression in RPE cells might partly account for the inhibitive effect of genistein on retinal neovascularization in vivo.

Angiogenesis Inhibitors↗

A faster converging snake algorithm to locate object boundaries.

A different contour search algorithm is presented in this paper that provides a faster convergence to the object contours than both the greedy snake algorithm (GSA) and the fast greedy snake (FGSA) algorithm. This new algorithm performs the search in an alternate skipping way between the even and odd nodes (snaxels) of a snake with different step sizes such that the snake moves to a likely local minimum in a twisting way. The alternative step sizes are adjusted so that the snake is less likely to be trapped at a pseudo-local minimum. The iteration process is based on a coarse-to-fine approach to improve the convergence. The proposed algorithm is compared with the FGSA algorithm that employs two alternating search patterns without altering the search step size. The algorithm is also applied in conjunction with the subband decomposition to extract face profiles in a hierarchical way.

Algorithms↗

Factors associated with adolescents' physical inactivity in Xi'an City, China.

PURPOSE: To explore the sociodemographic and environmental factors at community, school, and household levels associated with physical inactivity. METHODS: In a cross-sectional study in 2004, physical activity level was assessed using a validated questionnaire in 1787 students. Physical inactivity was defined as less than 150 min.wk of moderate activity (4-6 METs) or less than 60 min.wk of vigorous activity (> 6 METs). Sociodemographic and environmental information was recorded on self-administered questionnaires. Hierarchical multiple logistic models were developed based on a conceptual framework of factors related to physical activity. RESULTS: Overall, girls were twice as likely to be inactive. Adolescents aged 14 yr were 30% less likely to be inactive compared with those younger than 13 yr (95% CI: 0.5-0.9). Paternal education was inversely associated with inactivity (OR: 0.6, 95% CI: 0.4-0.9). Adolescents living in neighborhoods without sidewalks were 1.3 times more likely to be inactive (95% CI: 1.0-1.6). At the school level, lack of extracurricular exercise (OR: 1.3, 95% CI: 1.1-1.6) and fewer sports meetings (OR: 2.0, 95% CI: 1.4-2.9) were associated with physical inactivity. Difficult access to community recreational facilities (moderate OR: 1.4, 95% CI: 1.0-1.9; difficult OR: 1.7, 95% CI: 1.2-2.4) and concerns about safety in the neighborhood (OR: 2.1, 95% CI: 1.1-4.1) were associated with inactivity. There were some differences associated with physical inactivity between boys and girls. CONCLUSION: Strategies to promote physical activity in Chinese adolescents should integrate associated factors at household, school, and community levels and address the important gender differences in factors associated with physical inactivity in youth.

Adolescent↗

[Effects of iron deficiency anemia on immunity and infectious disease in pregnant women].

OBJECTIVE: To review the changes in immune function and incidence of infectious diseases in pregnant women with iron deficiency anemia (IDA), especially marginalde-ficiency of iron. METHODS: T lymphocyte subsets level (CD3+, CD4+ and CD8+), nature kill cells activity (CD16), interleukin-2 (IL-2) and serum IgA, IgG, IgM and complement C3 were determined in 3 different wormen groups, including 69 IDA pregnant women who were diagnosed by Hemoglobin, concentrations of free erythocyte porphrin and serum ferritin from 280 pregnant women during 30-38weeka of gestation, 52 random sampling normal pregnant women and 50 no pregnant women examined before marriage. RESULTS: The prevalenoe of IDA for pregnant women is 24.6%. The average concentration of Hb for pregnant women of IDA is 102.00(6.00 g/L The level of CD3+ and CD4+ cells, the ratio of CD4+/CD8+ cells, serum IL-2 as well as IgG levels in the pregnant women were significantly lower than that of those normal pregnant women (P < 0.01, P < 0.05, P < 0.05, P < 0.01). With the decreasing extent of Hb, these significant immunological indices of pregnant women will degrease. The incidence of infectious diseases in IDA pregnant women was significantly higher than that in normal pregnant women (P < 0.05). CONCLUSION: There are significantly effects of IDA on cellular immune function and infectious disease during pregnancy. The study on effects of IDA during pregnancy on nature kill cells activity (CD16) and incidence of infectious diseases during puerperium should be continued by increasing sample's number.

Adult↗

[A five-year observation on efficacy of revaccination in children of non-response to hepatitis B vaccine].

OBJECTIVES: To evaluate the long-term efficacy of revaccination in non-responder children to primary hepatitis B (HB) vaccination and to compare the efficacy of low-dose intradermal inoculation to that of routine-dose intramuscular inoculation. METHODS: 40 healthy non-responder children to primary HB vaccination identified by screening were given a three-dose revaccination randomly by intramuscular (n = 17, 10 microg per dose) or intradermal route (n = 23, 2 microg per dose) since September, 1999, and their blood specimens were collected regularly for testing for HB virus markers up to five years. Another 80 responder children to primary HB vaccination were also followed-up as controls without revaccination. By the end of five-year follow-up, HBsAg-specific lymphocyte response was investigated in vitro, and a booster dose (5 microg) was given to those with negative conversion of anti-HBs and their anamnestic responses were evaluated 12-14 days later. RESULTS: Serum anti-HBs did not reach 10 IU/L only in one of 40 non-responder children, who received intradermal revaccination. In the fifth year after revaccination, 50% of the non-responder children who received intramuscular revaccination still maintained anti-HBs of > or = 10 IU/L, though the rate was significantly lower than 85% in controls. Following the booster dose, a robust anamnestic response was developed in all of 8 intramuscular revaccinees and 11 controls but 16 of 18 intradermal revaccinees, who lost anti-HBs of > or = 10 IU/L over time, and geometric mean titers of anti-HBs climbed to 208, 105, and 549 IU/L, respectively. Secretions of HBsAg-specific interleukin-2 and -5 could be detected in peripheral blood mononuclear cell samples of more than 70% of non-responder children. Person-year infection rates of HB virus were 8.9% (8/89.9 person-years) for intradermal revaccinees, significantly higher than 3.6% (12/337.2 person-years) in controls, and 4.3% (3/70.2 person-years) for intramuscular revaccinees, approximating to that of controls, based on positive conversion of anti-HBc. CONCLUSIONS: Three-dose intramuscular revaccination did play an important immune protection for non-responder children to primary HB vaccination, but its efficacy could not reach the level of primary vaccination in responders. Low-dose intradermal inoculation was not as effective as route-dose intramuscular inoculation with the same doses in revaccination for non-responder children to primary HB vaccination.

Adolescent↗

[Prevalence of overweight and obesity and its associated risk factors in students aged 11-17 in Xi'an in 2004].

OBJECTIVE: To assess the magnitude of overweight and obesity and its associated sociodemographic factors in adolescents attending junior high schools in Xi'an, Shanxi province. METHODS: A total of 1 804 adolescents attending junior high schools in Xi'an (age: 11-17 years) were enrolled randomly from 30 schools in 6 districts in Xi'an. Overweight and obesity was categorized with body mass index (BMI) cutoffs from Working Group of Obesity in China (WGOC). Underweight was defined by BMI-Z < or = -2 s. Sociodemographic information was collected from the parents of the survey participants using self-administered, structured and precoded questionnaires. RESULTS: Overall 17.4% of adolescents were overweight or obese (overweight 11.2%; obesity 6.2%), but there was a marked gender difference in the prevalence with 20.2% of boys versus 14.4% of the girls being overweight or obese. The prevalence of underweight was 2.7%. In a multivariate model, age, residence, household wealth, and parents' BMI were significantly associated with overweight and obesity (P < 0.05). After having been adjusted for age and gender, the odds ratio of an adolescent being overweight and obese was 2.7 (95% CI: 1.8-4.0) folds higher in urban areas than in rural areas, and was 1.6 (95% CI: 1.04-2.5) folds higher for adolescents from rich families than those from poor families. An adolescent with one or both parents overweight was 1.8 (95% CI: 1.3-2.5) more likely to be overweight themselves compared to those with normal weight parents. CONCLUSIONS: Overweight and obesity is a major public health problem in adolescents in Xi'an. Overweight and obesity is more prevalent in younger boys from richer families living in urban districts and those whose parents were either overweight or obese.

Adolescent↗

[Study on maternal health care status to agricultural and nomadic counties in Tibet Autonomous Region of China].

OBJECTIVE: To understand the current situation of maternal health care and the association between maternal health care and relevant factors. METHODS: According to a cross sectional study design, 1512 mothers having children under 3 years old were drawn under stratified random sampling method and interviewed at their households in 15 counties, Tibet Autonomous Region of China. RESULTS: 77.6% of the pregnant women received at least one antenatal checkup with an average of 3.89 times while the rate of antenatal checkup over 5 times was 26.3%. The hospital delivery rate was 40.4% in this area. 83.9% of the women received education under the health care program during pregnancy and 66.2% of them were visited by health workers after delivery. Major factors of the antenatal checkups would include the resource of income, living in nomadic area, personal sanitation, antenatal health care education, mobilization of delivery at hospital, knowledge of antenatal health care etc. CONCLUSIONS: There had been great improvement in women's health care in this area as compared with the status in 1999, but the frequency of receiving antenatal checkup was still not enough and the rate of hospital delivery was also low as compared with 46 counties in western areas of China. Poor knowledge of health care during pregnancy seemed to be the major factor that limited the utilization of antenatal health care. Knowledge on health and common sense of health care should be disseminated to improve the antenatal care and to enhance the hospital delivery rate.

Agriculture↗