Body fat distribution and risk of diabetes among Chinese women

OBJECTIVE

To assess the relationship between measures of central and overall obesity and risk of diabetes.

DESIGN

Nested case-control study.

SETTING

Shanghai, China.

PARTICIPANTS

A total of 57 130 women were screened for diabetes at enrollment for the Shanghai Women's Health Study (SWHS), a population-based cohort study of Chinese women aged 40-70 y. In this study, 345 women diagnosed with diabetes and 2760 age-matched controls (eight controls per case), randomly selected from women who tested negative for urine glucose, were included.

RESULTS

Risk of diabetes increased significantly with increasing levels of obesity, particularly with measures of central obesity. Compared to those in the lowest quartile, women in the highest quartile of body mass index (BMI) (>/=26.57) and waist to hip ratio (WHR) (>/=0.855) had a 2.57-fold (95% CI 1.75-3.77) and a 6.05-fold (95% CI 4.05-9.04) increased risk of diabetes, respectively. The risk of diabetes was elevated with increasing WHR at all levels of BMI, while the positive association between BMI and diabetes was observed primarily among women with a low WHR. However, test for multiplicative interaction was not statistically significant.

CONCLUSIONS

Our data indicated that central obesity is a stronger risk factor for diabetes than overall obesity, suggesting that WHR may be a better indicator of risk of diabetes than BMI among Chinese women.

Isolation of linoleic acid as an estrogenic compound from the fruits of Vitex agnus-castus L. (chaste-berry)

A methanol extract of chaste-tree berry (Vitex agnus-castus L.) was tested for its ability to displace radiolabeled estradiol from the binding site of estrogen receptors alpha (ERalpha) and beta (ERbeta). The extract at 46 +/- 3 microg/ml displaced 50% of estradiol from ERalpha and 64 +/- 4 microg/ml from ERbeta. Treatment of the ER+ hormone-dependent T47D:A18 breast cancer cell line with the extract induced up-regulation of ERbeta mRNA. Progesterone receptor (PR) mRNA was upregulated in the Ishikawa endometrial cancer cell line. However, chaste-tree berry extract did not induce estrogen-dependent alkaline phosphatase (AP) activity in Ishikawa cells. Bioassay-guided isolation, utilizing ER binding as a monitor, resulted in the isolation of linoleic acid as one possible estrogenic component of the extract. The use of pulsed ultrafiltration liquid chromatography-mass spectrometry, which is an affinity-based screening technique, also identified linoleic acid as an ER ligand based on its selective affinity, molecular weight, and retention time. Linoleic acid also stimulated mRNA ERbeta expression in T47D:A18 cells, PR expression in Ishikawa cells, but not AP activity in Ishikawa cells. These data suggest that linoleic acid from the fruits of Vitex agnus-castus can bind to estrogen receptors and induce certain estrogen inducible genes.

Sociodemographic, behavioral, and reproductive factors associated with weight gain in Chinese women

OBJECTIVE

To examine whether certain sociodemographic, behavioral, and reproductive factors are associated with an increased weight gain in Chinese women.

DESIGN

Baseline survey data, including recalled past weight and measured current weight, from an ongoing prospective cohort study conducted in Shanghai, China.

SUBJECTS

The analytical sample included 75 039 nonpregnant women aged 40-70 y.

MEASUREMENTS

Statistical associations between certain sociodemographic, behavioral, and reproductive factors and weight gain were evaluated using multiple linear and logistic regression models.

RESULTS

Weight gain and waist-to-hip ratio (WHR) increased with age among pre- and postmenopausal women before age 55 y. Weight gain declined but WHR continued rising as aging among postmenopausal women over age 55 y. Lower education levels, more parity and earlier age at the first birth, and earlier menarcheal age were associated with a higher long-term weight gain and current body weight.

CONCLUSION

Age, education levels, parity, age at the first live birth, and menarcheal age were associated with long-term weight gain in Chinese women. However, these results concerning weight gain are based on recalled past weight and should be interpreted with caution. Further studies are needed to clarify the association of weight gain with lifestyle factors suggested by this study.

Symmetry breaking in the collinear phase of the J1-J2 Heisenberg model

The large J2 limit of the square-lattice J1-J2 Heisenberg antiferromagnet is a classic example of order by disorder where quantum fluctuations select a collinear ground state. Here, we use series expansion methods and a mean-field spin-wave theory to study the excitation spectra in this phase and look for a finite-temperature Ising-like transition, corresponding to a broken symmetry of the square lattice, as first proposed by Chandra et al. [Phys. Rev. Lett. 64, 88 (1990)]]. We find that the spectra reveal the symmetries of the ordered phase. However, we do not find evidence for a finite-T transition. We suggest a scenario for a T=0 transition based on quantum fluctuations.

Low body weight and its association with bone health and pubertal maturation in Chinese girls

OBJECTIVE

To investigate the prevalence of low body weight in Beijing pubertal girls and to establish the cut-off for body mass index (BMI) for underweight for Chinese pubertal girls.

DESIGN

Cross-sectional study.

SETTING

Three socioeconomic areas (rural, suburban and urban) in Beijing, China.

SUBJECTS

Random sample of 1214 adolescent girls aged 12-14 y from 13 middle schools.

RESULTS

Using a modified Chinese reference, the rate of low body weight (BMI<18) was 32.2% (95% CI 29.6-34.8%). Compared with desirable weight girls (BMI=18-21), girls with low body weight had a lower bone age, delayed breast and pubic hair development, a lower rate of menarche, lower distal one-third radius and ulna bone mineral content (BMC), bone mineral density and bone width. Logistic regression showed that BMI was one of the predictors of one-third ulna BMC after adjustment for confounding variables. When comparing BMI<18 vs BMI=18-21, the risk of BMC being less than the median increased by 82% (odds ratio 1.82, 95% CI 1.06-3.13). Thinness and stunting rates assessed by WHO recommended cut-offs are also reported.

CONCLUSIONS

High prevalence of low body weight (BMI<18) was found to be a major health problem among Beijing pubertal girls. BMI<18 is confirmed as the cut-off for delayed general growth and development for Chinese girls and for screening girls at risk of lower bone mineral status.

Elevation of blood beta-carboline alkaloids in essential tremor

BACKGROUND

beta-Carboline alkaloids are normal body constituents but are also potent tremor-producing chemicals that are naturally present in the food chain.

OBJECTIVE

To explore the hypothesis that high concentrations of beta-carboline alkaloids are associated with essential tremor (ET).

METHODS

One hundred cases and 100 controls were frequency matched on age, sex, and ethnicity. Blood concentrations of harmane and harmine were quantified by high-performance liquid chromatography, blinded to clinical information.

RESULTS

The mean log blood concentration of harmane was higher in cases than controls (0.72 +/- 0.53 vs 0.51 +/- 0.64 g(-10)/mL; p = 0.01). A nonparametric test on nontransformed data (median harmane = 5.21 g(-10)/mL in cases and 2.28 g(-10)/mL in controls) confirmed this difference (p = 0.005). The mean log blood concentration of harmine was 0.20 +/- 0.48 g(-10)/mL in cases and 0.10 +/- 0.65 g (-10)/mL in controls (p = 0.20). Log harmane concentrations were stratified based on the median value; 62% of cases vs 39% of controls had a high log harmane concentration (p = 0.001). Mean log harmane concentration was similar in the cases with (0.74 +/- 0.58 g(-10)/mL) and without (0.71 +/- 0.50 g(-10)/mL) an affected relative (p = 0.83).

CONCLUSIONS

Blood concentrations of harmane were measured in ET cases compared with controls. Concentrations were elevated in cases with and without a family history of ET.

Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58,515 women with invasive breast cancer and 95,067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19-1.45, P<0.00001) for an intake of 35-44 g per day alcohol, and 1.46 (1.33-1.61, P<0.00001) for >/=45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1% per 10 g per day, P<0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers=1.03, 95% CI 0.98-1.07, and for current smokers=0.99, 0.92-1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver.

[Effects of methotrexate on early pregnancy in mice]

Single s.c. injection of MTX at dosages of 8, 24 and 72 mg.kg-1 on day 7 of gestation was found to have a feticide effect in mice. The mortality of fetuses on day 13 of pregnancy was 18.0%, 55.5% and 60.3%, respectively. Treatment with MTX caused a decrease of serum progesterone level on day 13 of pregnancy. Treatment with MTX at a dosage of 24 mg.kg-1 on day 7-9 of gestation terminated total early pregnancy. MTX combined with hCG 10 U/mouse or progesterone 0.2 mg/mouse was shown to have antagonistic effect to terminate early pregnancy. Synergism of RU486 combined with MTX on termination of early pregnancy in mice was observed.

The radiation-induced bystander effect for clonogenic survival

It has long been accepted that the radiation-induced heritable effects in mammalian cells are the result of direct DNA damage. Recent evidence, however, suggests that when a cell population is exposed to a low dose of alpha particles, biological effects occur in a larger proportion of cells than are estimated to have been traversed by alpha particles. Experiments involving the Columbia University microbeam, which allows a known fraction of cells to be traversed by a defined number of alpha particles, have demonstrated a bystander effect for clonogenic survival and oncogenic transformation in C3H 10T(1/2) cells. When 1 to 16 alpha particles were passed through the nuclei of 10% of a C3H 10T(1/2) cell population, more cells were unable to form colonies than were actually traversed by alpha particles. Both hit and non-hit cells contributed to the outcome of the experiments. The present work was undertaken to assess the bystander effect of radiation in only non-hit cells. For this purpose, Chinese hamster V79 cells transfected with hygromycin- or neomycin-resistance genes were used. V79 cells stably transfected with a hygromycin resistance gene and stained with a nuclear dye were irradiated with the charged-particle microbeam in the presence of neomycin-resistant cells. The biological effect was studied in the neomycin-resistant V79 cells after selective removal of the hit cells with geneticin treatment.

Weight at birth and adolescence and premenopausal breast cancer risk in a low-risk population

We assessed breast cancer risk in relation to weight at birth and adolescence. In-person interviews were completed with the biological mothers of women aged 45 years and younger who participated in the Shanghai Breast Cancer Study in 1996-98 (288 cases, 350 controls). After adjustment for confounding, women who were 4000 g or more at birth were not at increased risk of breast cancer (odds ratio=0.7; 95% confidence interval 0.4-1.4) relative to women whose birth weight was 2500-2999 g. Compared with women of average perceived weight at age 15 years, no relation was apparent for heavier than average weight based on maternal report (odds ratio=0.7; 95% confidence interval 0.5-1.2) or self-report (odds ratio=1.0; 95% confidence interval 0.7-1.6). Perceived adolescent weight and height did not modify the association of birth weight with breast cancer risk. These results suggest that weight early in life is not related to premenopausal breast cancer risk in this low-risk population.

[Therapeutic effect of medical therapy upon undifferentiated nasopharyngeal carcinoma: analysis of 149 cases]

OBJECTIVE

To study the therapeutic effect and prognosis of undifferentiated nasopharyngeal carcinoma.

METHODS

149 patients with undifferentiated nasopharyngeal carcinoma, 4 at stage I, 33 at stage II, 73 at stage III, and 39 at stage IV according to the Fuzhou Staging Criteria of Nasopharyngeal Carcinoma 1992, were treated mainly by radiotherapy from 1999 to 2000: 78 of them underwent radiotherapy alone, 32 underwent radiotherapy combined with induced chemotherapy, and 39 underwent radiotherapy combined with synchronized chemotherapy. Relevant clinical data, especially the therapeutic effect upon and prognosis of the type, were analyzed.

RESULTS

Undifferentaited nasopharyngeal carcinoma accounts for 3.58% of nasopharyngeal carcinoma and was with a 5-year overall survival rate (OS) of 64.48%, a disease-free survival rate (DFS) of 60.35%, a distance-metastasis-free (DMF) survival rate of 77.05%, and a local recurrence free (LRF) survival rate of 80.13%. The key factors influencing prognosis were the stage of N and stage of international classification of cancer based on TNM.

CONCLUSION

Undifferentiated nasopharyngeal carcinoma is a rare type. Its prognosis is influenced mainly by the stage of N and TNM. Treatment maninly on radiotherapy is effective.

Toxicokinetics of tremorogenic natural products, harmane and harmine, in male Sprague-Dawley rats

Tremorogenic beta-carboline alkaloids are present in foodstuffs and beverages. Acute exposure to beta-carboline derivatives causes severe tremor; however, the disposition of these dietary contaminants remains unclear. This study was performed to evaluate toxicokinetics of harmane and harmine, two major beta-carboline alkaloids, in rats. Blood concentrations of both toxicants were quantified by high-performance liquid chromatography (HPLC). Following an intravenous injection (0.5 mg/kg), the concentration-time profiles of harmane or harmine fit well with a two-compartment model. While both compounds had comparable elimination t 1/2beta (24 and 26 min for harmane and harmine, respectively), the systemic clearance (CLs) for harmine (103.2 ml/kg/ml) was two times greater than that for harmane (52.2 ml/kg/ml). Accordingly, the area under the blood concentration-time curve (AUC) in harmane-treated rats was 2.7-fold greater than that in harmine-treated rats. Harmine appeared to distribute to tissues better than harmane, with a larger volume of distribution (V,d) (3.9 and 1.6 L/kg for harmine and harmane, respectively). After an oral dose (20 mg/kg), the absolute bioavailability (F) was 19% for harmane and 3% for harmine. Harmane was absorbed more slowly (lower Ka), yet more completely (higher Cmax' AUC, and F) than harmine. An oral administration of harmane resulted in blood harmine whose formation accounted for 13% of the ingested harmane, indicating a biotransformation of harmane to harmine. These results suggest that harmane is absorbed into the systemic circulation more completely than harmine. Upon entering the body, harmane can be metabolized to form harmine; the latter may better distribute to the tissue compartment.

Stem cells in neurodevelopment and plasticity

The processes of stem cell proliferation and differentiation during embryogenesis are governed by transcription factors that regulate the regional differentiation of the central nervous system (CNS). Do neural "stem" cells persisting in the postnatal CNS disobey this sequence of events? The division of neural progenitor cells is promoted by basic Fibroblast Growth Factor Fgf2 or Epidermal Growth Factor Egf. However, while the intraventricular administration of FgF2 during embryogenesis increases the generation of cortical pyramidal neurons, the same treatment in the adult CNS produces interneurons of the olfactory bulb. The competence of neural progenitor cells to respond to Fgf is dictated by nuclear transcription factors that constrain neuronal fates through time. Developmentally regulated transcriptional programs are regulated by cell interactions, as dividing cells check their molecular signature against that of their environment. Thus, cell surface interactions account for competitive phenomena among pools of cells, including the inhibitory effect of neurons on the division of their progenitors, and may also explain the "permissive" effects of non-CNS environments. The challenge remains to understand the genetic programs that control the fate of progenitor cells within the postnatal CNS and their regulation by stress, apoptosis and environmental perturbations. These programs are likely to be similar to gene cascades that control proliferation, differentiation and migration of progenitor cells at earlier stages of development.

Association of body size and fat distribution with risk of breast cancer among Chinese women

Most previous studies addressing the association of body size, weight change and body fat distribution with the risk of breast cancer were conducted in Western societies with a high proportion of overweight people. It remains unclear whether the dose-response relation observed in earlier studies can be extended to women with "normal" weight based on prevailing Western standards. To address this issue, we analyzed data from a population-based case-control study of breast cancer recently completed among Chinese women in urban Shanghai. In-person interviews and anthropometric measurements were completed for 1,459 women newly diagnosed with breast cancer from 25 to 64 years of age and 1,556 controls frequency-matched to cases on age. Unconditional logistic regression was employed to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CI) related to anthropometric variables and self-reported body weight. Currently measured weight, body mass index [BMI: weight (kg)/height(m)(2)] or height was each found to be positively related to risk of postmenopausal breast cancer in a dose-response manner, with ORs (95% CI) being 2.0 (1.4-3.0), 2.0 (1.2-3.2) or 1.7 (1.2-2.5), respectively, for the highest category of weight, BMI or height compared to the lowest category of these variables. These variables were unrelated to premenopausal breast cancer risk. Reported weight at ages >40 years and weight gain after age 20 were more predictive for postmenopausal breast cancer than weight at an earlier age. After adjustment for BMI, waist-to-hip ratio was related to an increased risk of premenopausal [OR = 1.7 (1.3-2.3) for the highest category compared to the lowest category] but not postmenopausal breast cancer. This study suggests that, even in a relatively thin Chinese population, weight gain and height are related to an increased risk of postmenopausal breast cancer, while central fat distribution was associated with premenopausal breast cancer. General weight control may be an effective measurement for breast cancer prevention.

Characteristics of spongiform leukoencephalopathy induced by heroin: MRI detection

OBJECTIVE

To elucidate the imaging characteristics of spongiform leukoencephalopathy induced by heroin and the diagnostic value of MRI examination.

METHODS

Eleven cases of heroin addiction were examined by MRI. The sequences included T1-weighted imaging (T1WI), T2-weighted imaging (T2WI) and fast fluid-attenuated inversion recovery pulse sequence (Flair).

RESULTS

Bilateral symmetrical lesions were located in the white matter of the cerebrum and cerebellum, the internal capsule in all cases, and the callosum in 6 cases. Elliptical lesions in the mesencephalon were found in two cases. These lesions were shown as hypointense signals on T1WI and hyperintense signals on T2WI and Flair's imaging. Cerebellar white matter suffered more severely, but the dentate nuclei were not invaded.

CONCLUSION

Heroin-induced spongiform leukoencephalopathy has characteristic patterns in MRI, which are very specific to this form of the disease.

Impairment of non-specific immunity in patients under persistent vegetative state resulting from trauma

OBJECTIVE

To investigate the immune response in patients under persistent vegetative state (PVS) resulting from trauma.

METHODS

Peripheral blood monocytes were obtained from 12 PVS patients (Group PVS)and individuals in normal control group by density gradient centrifugation; the enzyme linked immunosorbent assay kit was then used to measure monocyte HLA-DR antigen expression on the surface of peripheral blood monocytes before and after monocyte activation with either IFN-gamma or LPS.

RESULTS

Compared with normal control group, the peripheral blood monocyte HLA-DR antigen expression in the Group PVC fell significantly in PV S patients (P<0.001); the level of HLA-DR antigen express ion on the monocyte surface rose notably after stimulation with either IFN-gamma or LPS (P<0.01). As for PVS patients, it was still difficult to restore to normal (P<0.05).

CONCLUSIONS

The level of HLA-DR antigen expression on the sur face of peripheral blood monocytes in PVS patients decreases obviously. Therefore, the function of non-specific immunity in PVS patients is suppressed.