Xiao-Jun Wen - Academia.edu (original) (raw)

Papers by Xiao-Jun Wen

Hemoglobin

Hb Westmead or alpha 2 122(H5)His----Gln beta 2 is one of the most common hemoglobin variants in ... more Hb Westmead or alpha 2 122(H5)His----Gln beta 2 is one of the most common hemoglobin variants in Guangxi, a province in Southern China. The alpha 2-globin DNA sequence of a carrier for this variant was selectively amplified by the polymerase chain reaction and analyzed with the restriction enzyme Stu I. We found that this mutant globin was encoded at the alpha 2 locus and that the CAC----CAG mutation at codon 122 created a new Stu I restriction site. It is easy to detect this mutation by these methods.

Ethnicity & disease, 2010

Large-scale comparison and comprehensive estimate on the access to health care and preventive ser... more Large-scale comparison and comprehensive estimate on the access to health care and preventive services between Asian Americans/Pacific Islanders (AAPIs) and Non-Hispanic Whites (NHWs) has not been available. This study examines the racial disparities in access to health care and preventive services between AAPIs and NHWs in the USA. Cross-sectional study of access to health care and preventive services among AAPIs compared to NHWs, using data from Behavioral Risk Factor Surveillance System 2005 to 2007 among 908,154 respondents aged > or = 18 years. The percentages of AAPIs (aged > or = 18 years) who reported having a personal healthcare provider, a Pap test (women aged > or =18), a fecal occult blood test (aged > or = 50) a sigmoidoscopy/colonoscopy (aged > or = 50), a PSA test (men aged > or = 40), blood cholesterol checked (aged > or =18 yrs), and pneumococcal vaccination (aged > or = 65 yrs) were 76.7%, 83.1%, 27.5%, 47.5%, 35.5%, 74.2%, and 51.2%, respec...

Journal of physical activity & health, 2011

Most ischemic heart disease (IHD) prevention programs that promote physical activity (PA) have fo... more Most ischemic heart disease (IHD) prevention programs that promote physical activity (PA) have focused on overweight/obese populations. Persons with normal body mass index (BMI) may mistakenly think that they are not at risk for IHD and remain physically inactive. Studies exploring the risk of IHD and PA level among adults aged 45 years and older with normal weight are limited. Cross-sectional study to examine the prevalence of IHD and PA level among 94455 respondents aged 45 years and older with normal BMI using the 2007 Behavioral Risk Factor Surveillance System data. Approximately 50% of respondents reported low/inactive PA. The prevalence of IHD among persons with inactive, low, medium, and high PA was 16.6% (95% CI=15.1-18.1%), 9.6% (8.9-10.3%), 8.9% (8.3-9.6%), and 5.4% (4.9-5.9%). The adjusted odds ratios of IHD among persons with low, medium, and high PA compared with those with inactive PA was 0.68 (95% CI=0.59-0.79), 0.63 (0.54-0.73), and 0.49 (0.42-0.57). The percentage o...

Journal of environmental health, 2011

Despite the broad use of health-related quality of life (HRQOL) as one of the measurements to ass... more Despite the broad use of health-related quality of life (HRQOL) as one of the measurements to assess health status and effectiveness of health care and interventions, the impact of in-house mold exposure on HRQOL is unknown. The study described in this article examined the relationship between presence of visible in-house mold (PVIM) and HRQOL among adults. Data were analyzed from the 2005 and 2006 Behavioral Risk Factor Surveillance System (BRFSS) surveys that consisted of a random cross-sectional sample of 18,356 adults in four states. The authors examined the relationship between PVIM and three important indicators of the HRQOL by logistic regression analyses. Their results suggest that PVIM is independently associated with the indicators of HRQOL including mentally unhealthy, physically unhealthy, and total unhealthy days. Therefore, implementation of appropriate measures at the household level to eliminate or reduce in-house mold may improve individuals' HRQOL.

British Journal of Haematology

ABSTRACT

Nucleic Acids Research

Point mutations in GY and Ay globin gene promoters are associated with increased production of Gy... more Point mutations in GY and Ay globin gene promoters are associated with increased production of Gy and Ay globin, respectively. To determine whether an upstream promoter mutation could account for elevated Ay in a Black adolescent with AY-f3*-HPFH and sickle cell trait, we cloned the 13 kb BglII fragment containing both Y genes into phage lambda vector EMBL3. For one clone, the Ay upstream promoter showed no hybridization to a 19 bp oligonucleotide whose sequence centered at -117. Ay promoter sequence data for this mutant clone revealed a 13 bp deletion which eliminated the AY distal CCAAT box. Amplified Ay genomic DNA of this and a similar case showed hybridization to both deletion-mutant and normal oligonucleotide probes. We propose that this 13 bp deletion removes part of the binding site for a repressor protein which is abundant in adult erythroid cells.

AIDS education and prevention : official publication of the International Society for AIDS Education, 2002

Nucleic Acids Research, 1988

Hemoglobin, 1992

Three primers were designed, one specific for alpha 1-globin DNA, a second for alpha 2-globin DNA... more Three primers were designed, one specific for alpha 1-globin DNA, a second for alpha 2-globin DNA, and a third that is common for both alpha 1- and alpha 2-globin DNA. These three primers can be applied for selective amplification of the two globin DNA fragments, which is useful for identification of nondeletional types of Hb H disease. Fifty-nine DNA samples of Hb H patients from Guangxi were studied by selective amplification, and 27 cases (45.8%) were confirmed as nondeletional types. Of these, 22 (81.5%) had the Hb Constant Spring (CS) mutation and one had the Hb Quong Sze (QS) mutation; both were identified by hybridization with synthesized oligonucleotide probes. Nondeletional Hb H disease in Guangxi seems to be more severe than the deletional types. The average hemoglobin level of the nondeletional Hb H/CS (--/alpha alpha) is 6.8 g/dl, which is lower than that of the deletional types (7.9 g/dl), while the levels of Hb H and Hb Bart's were much higher in the patients with Hb H/CS than in those with the deletional types.

Hemoglobin, 1991

The polymerase chain reaction technique combined with restriction map analysis with Msp I and hyb... more The polymerase chain reaction technique combined with restriction map analysis with Msp I and hybridization with synthetic oligonucleotide probes has been used to identify Hb Quong Sze [alpha 125(H8)Leu----Pro] in a Chinese family in Guangxi (Quong Sze), P. R. China. Our data and those described in an earlier publication (1) indicate that the Hb Quong Sze carriers originate from the same province of the People's Republic of China, namely Guangxi.

Experimental Eye Research, 2003

This study examines the microtubule configuration and its close association with the Golgi comple... more This study examines the microtubule configuration and its close association with the Golgi complex and Golgi-derived membranous vesicles in elongating fiber cells of the rat lens. Since fiber cells elongate tremendously during lens differentiation, we hypothesize that a microtubule-based motor system exists in the elongating fiber cells for transporting important membrane proteins and organelles to the target regions for cell growth. The newly synthesized membrane proteins are known to be transported from the trans-Golgi network in the form of vesicles to the target plasma membrane. By thin-section TEM, we observed a large number of vesicles of various sizes and shapes randomly distributed throughout the cytoplasm of elongating fiber cells. Both Golgi complex and vesicles exhibited characteristic normal structural features seen in other cell types and thus represented real vesicular organelles in the fiber cells. A large number of microtubules were regularly arranged into bundles parallel to the long axis of fiber cells as examined in both longitudinal and cross-section views. Many of these microtubules were closely associated or in intimate contact with the Golgi complex and vesicles in elongating fiber cells. The microtubule polarity assay revealed that microtubules exhibited a unidirectional polarity for the entire length of fiber cells as examined in both anterior and posterior cortical fiber segments. Namely, the minus end of microtubules was towards the anterior lens pole while the plus end was headed towards the posterior pole. This suggests that multiple molecular motors such as kinesin and dynein are needed for carrying the vesicles to both lens poles, since conventional kinesin is known to transport vesicular organelles towards the plus end whereas cytoplasmic dynein carries them towards the minus end of microtubules. By immunoblot analysis, we indeed detected the presence of both kinesin (120 kD) and dynein (70 kD) in homogenate prepared from lens cortical fibers. Moreover, immunogold TEM demonstrated that the aquaporin 0 (formally MIP26) antibody was localized on the membranous vesicles as well as plasma membranes of the cortical fiber cells. This study suggests that a microtubule-based motor system exists in the lens and plays an important role in transporting membrane proteins such as aquaporin 0 in the vesicles during fiber cell differentiation and elongation. q

Experimental Eye Research, 2000

Medicine, 2016

Long-term exposure to ground-level ozone is associated with increased risk of morbidity and morta... more Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy.We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels.We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in ...

Objective. Ischemic heart disease (IHD) is one of the most common health threats to the adult pop... more Objective. Ischemic heart disease (IHD) is one of the most common health threats to the adult population of the U.S. and other countries. The objective of this study was to examine the association between exposure to elevated annual average levels of Particulate matter 2.5 (PM 2.5 ) air quality index (AQI) and IHD in the general population.