Leptin levels in cord blood and anthropometric measures at birth: a systematic review and meta-analysis

The role of intrauterine environment in the development of obesity is increasingly recognised. Adipokines and specifically leptin have been examined as potential biomarkers predicting early development of obesity. We conducted a systematic review and meta-analysis of the epidemiological evidence for the association between leptin levels in cord blood and anthropometric measurements at birth in healthy mother-newborn pairs. A PubMed search was performed between 1994 and 2009 and manual search of reference lists of retrieved articles. Forty-four studies met the inclusion criteria set. All studies reported a positive correlation between leptin levels and birthweight. The combined correlation coefficient (r) was 0.46 [95%CI 0.43, 0.50]. Leptin levels explained 21% of variation in birthweight. Results were similar in males (r=0.55; 0.40, 0.68) and females (r=0.60; 0.50, 0.69), and between Caucasians (r=0.45; 0.39, 0.51) and eastern Asian populations (r=0.47; 0.37, 0.55). Statistically significant positive correlations were also found for birth length (r=0.29; 0.23, 0.34) and ponderal index (r=0.36; 0.31, 0.41). There was no indication of publication bias (Egger's test P-value=0.23). This meta-analysis shows a clear but moderate correlation between leptin levels in cord blood and birthweight that is observed in different population groups.     

Food‐borne illness in the United States: Geographic and demographic patterns

Food‐borne illness in the United States in 1990 is first defined with the construction of List A, based on ICD‐9‐CM, 4th ed., codes for diseases. Using this list, the geographical and demographic patterns are presented using national data on physician office visits, hospital discharge certificates, and death certificates. Children under 14 years old accounted for the largest percentage of physician office visits. In terms of hospital discharge certificates, persons 65 years and older accounted for the largest percentage. In terms of deaths, the elderly 65 years and older were the largest category. Variations by sex, region, and race are presented.     

PCB concentrations in shrimp from major import markets and the United States

Currently, environmental studies describing levels of polychlorinated biphenyls (PCBs) in imported shrimp are limited, particularly studies of aquaculture shrimp. In the present study, we measured concentrations of the 209 PCB congeners in 84 uncooked, warm-water shrimp samples from the United States and 14 other countries in three continents. Total PCB and dioxin-like PCB (DL-PCB) levels were not significantly different between wild-caught and farm-raised shrimp, and the distribution of total PCB levels did not vary considerably by country of origin although significant differences were observed in some cases. Regional trends in both total PCB and DL-PCB concentrations were observed, with the highest concentrations measured in shrimp from North America followed by Asia and then South America. The lower chlorinated homologues (i.e., mono-, di-, and tri-PCBs) generally comprised a greater fraction of the total levels measured in farm-raised shrimp and shrimp from Asia and South America whereas higher chlorinated homologues (i.e., hepta-, octa-, nona-, and deca-PCBs) contributed more to levels in wild-caught shrimp and shrimp from North America. Estimated daily intake of PCBs associated with shrimp consumption ranged from 2?pg/kg/d (shrimp from South America) to 15?pg/kg/d (shrimp from North America). Results from the present study were comparable to other studies conducted recently and demonstrate that exposure to PCBs from consumption of farm-raised and wild-caught shrimp imported from different regions are not likely to pose any health risks.     

Race and preference-based health-related quality of life measures in the United States

Background  

Health-related quality of life instruments (HRQoL) are widely used to produce measures that summarize population health and to inform decision-making and health policy. Although the literature about the relationship between health and race in the United States is quite extensive, there is a lack of studies that comprehensively examine the relationship between race and preference-based HRQoL. Given the widespread use of these measures, it becomes important to understand the extent of the race differences in HRQoL scores and factors associated with any such differences.     

Associations between concentrations of uric acid with concentrations of vitamin A and beta-carotene among adults in the United States

Our objective was to examine the cross-sectional associations between concentrations of vitamin A and beta-carotene, a major source of vitamin A, with concentrations of uric acid in a nationally representative sample of adults from the United States. We conducted a cross-sectional study using data from up to 10893 participants aged ≥20 years of National Health and Nutrition Examination Survey from 2001 to 2006. Concentrations of uric acid adjusted for numerous covariates increased from 305.8 μmol/L in the lowest quintile of vitamin A to 335.3 μmol/L in the highest quintile (p for linear trend <0.001). The prevalence ratio for hyperuricemia also increased progressively across quintiles of serum vitamin A reaching 1.82 (95% confidence interval [CI]: 1.52, 2.16; p for linear trend <0.001) in the top quintile in the maximally adjusted model. Adjusted mean concentrations of uric acid decreased progressively from quintile 1 (333.8 μmol/L) through quintile 4 of concentrations of beta-carotene and were similar for quintiles 4 (313.5 μmol/L) and 5 (313.8 μmol/L). Concentrations of beta-carotene were inversely associated with hyperuricemia (adjusted prevalence ratio comparing highest with lowest quintile = 0.61; 95% CI: 0.52, 0.72; p for linear trend <0.001). Concentrations of uric acid were significantly and positively associated with concentrations of vitamin A and inversely with concentrations of beta-carotene. These cross-sectional findings require confirmation with experimental studies of vitamin A and beta-carotene supplementation.     

Self-reported health in Poland and the United States: a comparative analysis of demographic, family and socioeconomic influences

This study compares the social determinants of individual health between the United States, a capitalist society, and Poland, a 'post-communist' society. The effects of demographic factors, family characteristics and socioeconomic status on self-reported health are estimated with OLS regression using data from the 1994 American and Polish General Social Surveys. The results show lower self-reported health and more rapid declines in health for people over 60 in Poland than in the United States. Also, in Poland, women report worse health than do men while the opposite is found for the United States. The relationships between education, income and health were stronger in the United States than in Poland. Age, gender and SES may operate differently in the two countries because of a gap in social development (e.g. varying living standards and styles, health care systems and cultural attitudes) between the West and the former Eastern Europe.     

Program practices and demographic factors associated with federal funding for the Safe Routes to School program in the United States

In 2005, the United States Congress authorized $612 million for use in implementing the US Safe Routes to School program to address physical inactivity, air quality, safety and traffic near schools. Each US state developed administrative practices to implement the program. Based on state-specific annual obligations, on average, states have obligated 44% of available funds. State project obligations were directly associated with programmatic factors, including broader adherence to federal agency administrative guidance objectives and the number of years for which the states obligated new projects and indirectly associated with student enrollment and state child poverty. Research and policy recommendations are discussed.     

美国鼓励仿制药替代使用政策与措施研究

目的：分析美国鼓励仿制药替代使用的立法过程、政策措施以及关键要素，为我国仿制药经一致性评价后制定替代使用政策提供建议。方法：通过查阅美国联邦法律、各州法律、指南文件、国内外文献等，全面分析美国鼓励仿制药替代使用的基本原则、监管理念和实施挑战。结论：美国仿制药替代法律的制定经历探索、发展和调整三个阶段。医师、药师和患者是美国各州法律鼓励仿制药替代的关键要素，联邦政府和FDA通过橙皮书、分级医保支付和开展认知教育的途径指导和影响仿制药替代。建议我国以尊重患者为基本原则，将鼓励仿制药替代写入法律，明确界定仿制药替代使用范围；建立具有替代决策支持工具的电子处方系统；加强宣传教育提高仿制药认知度。     

Uranium and thorium in urine of United States residents: reference range concentrations.

We measured uranium and thorium in urine of 500 U. S. residents to establish reference range concentrations using a magnetic-sector inductively coupled argon plasma mass spectrometer (ICP-MS). We found uranium at detectable concentrations in 96.6% of the urine specimens and thorium in 39.6% of the specimens. The 95th percentile concenetration for uranium was 34.5 ng/L (parts per trillion); concentrations ranged up to 4080 ng/L. Thorium had a 95th percentile concentration of 3.09 ng/L; concentrations ranged up to 7.7 ng/L.     

Estimating risk from ambient concentrations of acrolein across the United States

BACKGROUND: Estimated ambient concentrations of acrolein, a hazardous air pollutant, are greater than the U.S. Environmental Protection Agency (EPA) reference concentration throughout the United States, making it a concern for human health. However, there is no method for assessing the extent of risk under the U.S. EPA noncancer risk assessment framework. OBJECTIVES: We estimated excess risks from ambient concentrations of acrolein based on dose-response modeling of a study in rats with a relationship between acrolein and residual volume/total lung capacity ratio (RV/TLC) and specific compliance (sC(L)), markers for altered lung function. METHODS: Based on existing literature, we defined values above the 90th percentile for controls as "adverse." We estimated the increase over baseline response that would occur in the human population from estimated ambient concentrations of acrolein, taken from the U.S. EPA's National-Scale Air Toxics Assessment for 1999, after standard animal-to-human conversions and extrapolating to doses below the experimental data. RESULTS: The estimated median additional number of adverse sC(L) outcomes across the United States was approximately 2.5 cases per 1,000 people. The estimated range of additional outcomes from the 5th to the 95th percentile of acrolein concentration levels across census tracts was 0.28-14 cases per 1,000. For RV/TLC, the median additional outcome was 0.002 per 1,000, and the additional outcome at the 95th percentile was 0.13 per 1,000. CONCLUSIONS: Although there are uncertainties in estimating human risks from animal data, this analysis demonstrates a method for estimating health risks for noncancer effects and suggests that acrolein could be associated with decreased respiratory function in the United States.     

Circulating phylloquinone concentrations of adults in the United States differ according to race and ethnicity

Differences in micronutrient status are reported to contribute to racial and ethnic differences in chronic diseases. Diseases related to vitamin K are reported to differ by race and ethnicity, but it is unclear if circulating vitamin K concentrations similarly differ. We examined racial and ethnic differences in serum phylloquionone (K1) in the Multiethnic Study of Atherosclerosis (MESA) (mean ± SD age = 62 ± 10 y; 52% female; 262 white, 180 African American, 169 Hispanic, 93 Chinese American). Overall, 25% had serum K1 <0.1 nmol/L (the lower limit of detection). The prevalence of low serum K1 was 4% in Chinese Americans compared with 24% of whites, 29% of African Americans, and 33% of Hispanics. Compared with whites, Chinese Americans were significantly less likely to have serum K1 <0.1 nmol/L [OR (95% CI): 0.23 (0.09-0.23), adjusted for serum TG, K1 intake, age, sex, BMI, smoking, total cholesterol, site, season, and lipid-lowering medication use]. African Americans and Hispanics had similar odds to whites for having serum K1 <0.1 nmol/L [OR(95% CI): 1.30 (0.79-2.15) and 1.19 (0.66-2.15), respectively; fully adjusted]. In participants with detectable concentrations (n = 523), (natural log) serum K1 was higher in the Chinese Americans compared with whites, African Americans, and Hispanics (geometric mean ± SEM = 2.2 ± 0.1 nmol/L vs. 1.2 ± 0.1 nmol/L, 1.5 ± 0.1 nmol/L, and 1.1 ± 0.1 nmol/L, respectively, adjusted for serum TG, K1 intake, and additional covariates; all P < 0.001). These findings suggest circulating K1 differs by race and ethnicity in U.S. adults, especially among those of Chinese American descent, which merits consideration in the design and interpretation of future population-based and clinical studies of vitamin K and related diseases.     

Fiber intakes and anthropometric measures are predictors of circulating hormone, triglyceride, and cholesterol concentrations in the women's health trial

The unhealthy eating patterns and obesity among women in the U.S. are indicated by changes in biomarkers, such as insulin, lipoproteins, and estradiol, that are risk factors for breast cancer and cardiovascular diseases. This article models the inter-relations among diet, serum insulin, estradiol, and sex hormone binding globulin (SHBG) concentrations, plasma LDL and HDL cholesterol, and net triglyceride concentrations, using the data at baseline and 12 mo on 379 and 615 postmenopausal women in the Control and Intervention groups, respectively, of the Women's Health Trial: Feasibility Study in Minority Populations. Subjects in the Intervention group received detailed advice over a period of 1 y for reducing fat intakes and increasing the consumption of whole grains and fruits and vegetables. The main findings were that there were significant differences between the Control and Intervention groups in the changes from baseline to 12 mo in LDL and HDL cholesterol and SHBG concentrations. Second, using a comprehensive random effects modeling framework, the ratio of fiber to energy intake was significantly associated (P < 0.05) with lower insulin and triglyceride levels, and with a higher HDL cholesterol concentration in the Intervention group. Third, the subjects' waist-to-hip ratio and BMI were significantly associated with insulin, SHBG, LDL and HDL cholesterol, and triglyceride concentrations. Fourth, insulin levels were significantly negatively associated with SHBG and HDL cholesterol, and positively associated with LDL cholesterol, triglyceride, and estradiol concentrations. Overall, weight loss, especially around the waist, and increased fiber intakes are likely to be beneficial for lipid, cholesterol, and hormone profiles of U.S. women.     

Trends in blood folate and vitamin B-12 concentrations in the United States, 1988 2004

BACKGROUND: Monitoring the folate status of US population groups over time has been a public health priority for the past 2 decades, and the focus has been enhanced since the implementation of a folic acid fortification program in the mid-1990s. OBJECTIVE: We aimed to determine how population concentrations of serum and red blood cell (RBC) folate and serum vitamin B-12 have changed over the past 2 decades. DESIGN: Measurement of blood indicators of folate and vitamin B-12 status was conducted in approximately 23,000 participants in the prefortification third National Health and Nutrition Examination Survey (NHANES III; 1988-1994) and in approximately 8000 participants in 3 postfortification NHANES periods (together covering 1999-2004). RESULTS: Serum and RBC folate concentrations increased substantially (by 119-161% and 44-64%, respectively) in each age group in the first postfortification survey period and then declined slightly (by 5-13% and 6-9%, respectively) in most age groups between the first and third postfortification survey periods. Serum vitamin B-12 concentrations did not change appreciably. Prevalence estimates of low serum and RBC folate concentrations declined in women of childbearing age from before to after fortification (from 21% to <1% and from 38% to 5%, respectively) but remained unchanged thereafter. Prevalence estimates of high serum folate concentrations increased in children and older persons from before to after fortification (from 5% to 42% and from 7% to 38%, respectively) but decreased later after fortification. CONCLUSIONS: The decrease in folate concentrations observed longer after fortification is small compared with the increase soon after the introduction of fortification. The decrease is not at the low end of concentrations and therefore does not raise concerns about inadequate status.     

The United States:

Examines the need for uniform national policy for the provision of long-term care (LTC) services at an affordable price with access for all in need; points up the relationship between LTC issues and acute care policy; outlines seven basic principles for a comprehensive LTC system; lists problems to be solved and proposes alternative solutions for issues of chronicity, access, and cost control; and urges long-range comprehensive policy reform for health care delivery and financing.