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Biomedical subjects

X Rao

Publications and source records attributed to X Rao.

18 recordsLinked to original sources
PubMed2005

Results of surgical treatment of congenital cystic lung disease.

OBJECTIVE: To review the experience with surgical intervention for congenital cystic lung disease (CCLD). METHODS: From April 1988 to December 2001, 68 patients were diagnosed and treated surgically for CCLD. There were 27 males and 41 females ranging in age from 2 to 65 years. The majority of the cases were diagnosed by history, clinical manifestations and chest radiography or computerized tomography (CT). There were 25 (36.8 %) right-sided and 43 (63.2 %) left-sided cystic lung lesions. Four patients had massive bleeding and needed urgent or emergency operation. Pneumonectomy, lobectomy, and/or segmentectomy were performed. RESULTS: 29 (42.6 %) patients underwent lobectomy, 25 (36.8 %) had total pneumonectomy, 9 (13.2 %) lobectomy plus segmentectomy, and 5 (7.4 %) bilobectomy. During the operation, left-sided pulmonary sequestration was confirmed in 3 patients. No death occurred in this series. Diagnoses were confirmed by pathology in all cases. Two patients had malignant lesions arising from multicystic lung lesions. CONCLUSIONS: A history of recurrent pneumonia, often with hemoptysis and subsequent dyspnea, should raise the suspicion of CCLD. The diagnosis can be confirmed by chest X-ray and CT preoperatively, and early surgical intervention may avoid the development of serious complications. Delayed diagnosis and surgical management usually result in significant morbidity and mortality.

Adolescent↗
PubMed2002

Patterns of lung function in asymptomatic nonsmoking men and women in the People's Republic of China.

PURPOSE: To evaluate patterns of lung function in healthy, working Chinese men and women in different geographic areas of the People's Republic of China (PRC). METHODS: We conducted lung function tests on 2926 asymptomatic, never smoking Chinese men and women aged 35-56 years residing in or around Beijing and Guangzhou. Within each of these locations, separate urban and rural samples were recruited. RESULTS: Age and height adjusted lung function was greater in Beijing than in Guangzhou, and within each city for residents of rural vs. urban areas. Among women, estimated rates of lung aging were greater in Beijing than in Guangzhou, and in urban vs. rural areas. Both FEV(1) and FVC exhibited a curvilinear association with body mass index. CONCLUSIONS: Lung function data from this largely working cohort exhibited marked geographic and urban-rural differences in this never smoking, adult Chinese cohort. Such variation is not uncommon and may reflect differences in body size, diet, and environmental and occupational exposures across these different settings. Caution should be used in applying published reference equations to populations from different parts of the PRC.

Adult↗
PubMed2001

Real-time monitoring of formaldehyde-induced DNA-lysozyme cross-linking with piezoelectric quartz crystal impedance analysis.

A novel method for monitoring, in real time, the formaldehyde (FA)-induced DNA-protein cross-linking process with the piezoelectric quartz crystal impedance (PQCI) technique is proposed. The method was used to monitor FA-induced DNA-lysozyme cross-link formation. Lysozyme was directly immobilized on the silver electrode surface of a piezoelectric quartz crystal by adsorption. The lysozyme-coated piezoelectric sensor was in contact with FA and DNA solutions. The time courses of the resonant frequency and equivalent circuit parameters of the sensor during the cross-linking were simultaneously obtained and are discussed in detail. On the basis of the feature of the multi-dimensional information provided by the PQCI technique, it was concluded that the observed frequency decrease could be mainly ascribed to the mass increase resulting from the cross-linking. According to the frequency decrease with time, the kinetics of the cross-linking process were quantitatively studied. A piezoelectric response model for the cross-linking was theoretically derived. Fitting the experimental data to the model, the kinetic parameters, such as the binding and dissociation rate constants (k(1) and k(-1)) and the cross-linking equilibrium constant (Ka), were determined. At 37 degrees C, the k(1), k(-1) and Ka values obtained were 7.0 (+/-0.1) x 10(-5) (microg ml(-1))(-1) s(-1), 6.6 (+/-0.1) x 10(-3) s(-1) and 1.06 (+/-0.02) x 10(-2) (microg ml(-1))(-1), respectively.

DNA↗
PubMed2001

[Dietary intake of antioxidant vitamins and personal demographic characteristics of Guangdong residents].

The study aim at revealing the associations between the intake of dietary antioxidant vitamins and personal characteristics on age, sex, education, working status and household gross income etc. The intake of antioxidant vitamins in a population of Guangdong Province was studied. A total of 418 males and 503 females, aged 25-84 year were interviewed, and questionnaires on socio-demography and on a 12-month food intake frequency (FFQ) were completed in 1995. The daily average intake of antioxidant vitamins and energy was higher in male than in female. Older subjects consumed lesser antioxidant vitamins. The vitamin E intake of higher education persons as well as high family income females (> 15001RMB) was higher. Individual business owners and farmers consumed lesser antioxidant vitamins than the other counterparts. The highest vitamin E intake was found in the currently unemployed men and retired women. BMI was positively associated with the intake of antioxidant vitamins excepted for the obesity group. The result suggests that the consumption of antioxidant vitamins varies with characteristics of socio-demographic status. Health promotion programs, such as suggestions on eating more fruits and vegetables should be targeted at the elderly, the less educated, lower income families and rural community.

Adult↗
PubMed2000

Comparison of electrocardiographic findings between Northern and Southern Chinese population samples.

BACKGROUND: Cardiovascular disease is rare in China, but there are few data on the prevalence of electrocardiographic (ECG) abnormalities in Chinese populations. METHODS: The ECG surveys were carried out in four Chinese population samples, in a total of 9,666 adults aged 35-54 in Beijing and Guangzhou, China from 1981 to 1984. Twelve-lead resting ECG tracings were coded by the Minnesota Code. RESULTS: Prevalence per 1,000 of abnormal ECG ranged from 77.4 to 209.8, and was higher for men than women and higher for Guangzhou than Beijing. Prevalence per 1,000 of major abnormalities in Guangzhou was 29.8 for men and 78.4 for women, higher than the 18.4 and 29.6 for counterparts in Beijing. The ECG changes attributed in 'Western' populations to coronary heart disease (CHD), such as large Q waves (Minnesota Code 1-1, 1-2) and ST-T abnormalities, were similar between Beijing and Guangzhou men, but Guangzhou women had much higher prevalence of ST-T abnormalities than Beijing women. Other ECG abnormalities such as A-V block, left branch bundle block, and left ventricular hypertrophy were rare in people of both sites. CONCLUSIONS: Compared with similar data from the US, these Chinese populations had a relatively low prevalence of ECG abnormalities putatively related to CHD. This corresponds with the low incidence of CHD in the Chinese population. However, within the Chinese populations of this study, a high abnormality rate appeared in a population with low incidence of CHD and hypertension (Guangzhou women). Reasons why ECG abnormalities do not parallel prevalence levels of CHD and hypertension remain to be elucidated.

Adult↗
PubMed1998

Inhibition of Stat1-mediated gene activation by PIAS1.

STAT (signal transducer and activator of transcription) proteins are latent cytoplasmic transcription factors that become activated by tyrosine phosphorylation in response to cytokine stimulation. Tyrosine phosphorylated STATs dimerize and translocate into the nucleus to activate specific genes. Different members of the STAT protein family have distinct functions in cytokine signaling. Biochemical and genetic analysis has demonstrated that Stat1 is essential for gene activation in response to interferon stimulation. Although progress has been made toward understanding STAT activation, little is known about how STAT signals are down-regulated. We report here the isolation of a family of PIAS (protein inhibitor of activated STAT) proteins. PIAS1, but not other PIAS proteins, blocked the DNA binding activity of Stat1 and inhibited Stat1-mediated gene activation in response to interferon. Coimmunoprecipitation analysis showed that PIAS1 was associated with Stat1 but not Stat2 or Stat3 after ligand stimulation. The in vivo PIAS1-Stat1 interaction requires phosphorylation of Stat1 on Tyr-701. These results identify PIAS1 as a specific inhibitor of Stat1-mediated gene activation and suggest that there may exist a specific PIAS inhibitor in every STAT signaling pathway.

Amino Acid Sequence↗
PubMed1998

[Yishen huanshuai recipe retard progression of chronic renal failure].

OBJECTIVE: To investigate the effect of Yishen Huanshuai recipe (YSHSR) on the progression of chronic renal failure (CRF). METHODS: Forty-six patients with CRF were divided into two groups: group A (self-controlled group, n = 18), whose treatment was subdivided into two stages. During the first stage, the patients treated with low protein diet and controlling blood pressure, while in the second stage, YSHSR was given. Group B(n = 28), whose treatment plan was similar with that of group A in second stage. The rate of progression of CRF was estimated by slope of the creatinine reciporcal (dl/mg) with time (month). RESULTS: Mean slope of the creatinine reciprocal with time from the group A during the first stage was -0.0104 +/- 0.0021, while during the second stage, it was -0.0034 +/- 0.0018. There was significant difference between them (P < 0.05). Mean slope from the group B was -0.0047 +/- 0.0020. There was also significant difference between that from the group B and that from the group A during the first stage (P < 0.05). CONCLUSIONS: Low protein and controlling blood pressure plus YSHSR therapy could markedly retard the rate of progression of CRF.

Adult↗
PubMed1997

Specific inhibition of Stat3 signal transduction by PIAS3.

The signal transducer and activator of transcription-3 (Stat3) protein is activated by the interleukin 6 (IL-6) family of cytokines, epidermal growth factor, and leptin. A protein named PIAS3 (protein inhibitor of activated STAT) that binds to Stat3 was isolated and characterized. The association of PIAS3 with Stat3 in vivo was only observed in cells stimulated with ligands that cause the activation of Stat3. PIAS3 blocked the DNA-binding activity of Stat3 and inhibited Stat3-mediated gene activation. Although Stat1 is also phosphorylated in response to IL-6, PIAS3 did not interact with Stat1 or affect its DNA-binding or transcriptional activity. The results indicate that PIAS3 is a specific inhibitor of Stat3.

Amino Acid Sequence↗
PubMed1997

Prediction of protein supersecondary structures based on the artificial neural network method.

The sequence patterns of 11 types of frequently occurring connecting peptides, which lead to a classification of supersecondary motifs, were studied. A database of protein supersecondary motifs was set up. An artificial neural network method, i.e. the back propagation neural network, was applied to the predictions of the supersecondary motifs from protein sequences. The prediction correctness ratios are higher than 70%, and many of them vary from 75 to 82%. These results are useful for the further study of the relationship between the structure and function of proteins. It may also provide some important information about protein design and the prediction of protein tertiary structure.

Amino Acid Sequence↗
PubMed1996

Constitutive activation of STAT5 by the BCR-ABL oncogene in chronic myelogenous leukemia.

Using chronic myelogenous leukemia (CML) as a model, we tested the hypothesis that cytokine-independent growth of leukemia cells results from aberrant activation of cytokine signaling pathways. The STAT5 (signal transducer and activator of transcription) protein, which is activated transiently in normal myeloid cells by cytokines such as GM-CSF (granulocyte-macrophage colony stimulating factor), was constitutively activated in cell lines derived from CML patients, even in the absence of GM-CSF. STAT5 was also activated in primary mouse bone marrow cells acutely transformed by the CML-specific BCR-ABL oncogene, but not by the serine kinase oncogene v-MOS. Reconstitution experiments in non-hematopoietic cells show that STAT5 activation by BCR-ABL occurs independent of cytokines. Results using BCR-ABL mutants which specifically uncouple connections to known signal transduction pathways show that STAT5 activation is kinase dependent and correlates directly with ability to confer cytokine independent growth in hematopoietic cells. BCR-ABL also activates JAK kinases, which may provide a mechanism for STAT activation. These findings are consistent with a role for STAT5 in hematopoietic transformation by BCR-ABL.

Animals↗
PubMed1996

Changes in average blood pressure and incidence of high blood pressure 1983-1984 to 1987-1988 in four population cohorts in the People's Republic of China. The PRC-USA Cardiovascular and Cardiopulmonary Epidemiology Research Group.

OBJECTIVE: To assess comparative changes in systolic and diastolic blood pressure and incidence of high blood pressure over 4 years, and factors related to these changes, in northern and southern, urban and rural adults in the People's Republic of China. SETTING: This is a prospective study of populations surveyed by standardized methods in 1983-1984 and 1987-1988 in north China, Beijing area steel mill workers and farmers, and south China, Guangzhou area shipyard workers and farmers. SUBJECTS: The subjects were 8805 men and women aged 35-54 years at baseline (1983-1984), of whom 7338 were non-hypertensive (systolic blood pressure < 140, diastolic blood pressure < 90 mmHg, not being administered antihypertensive drugs). MAIN OUTCOME MEASURES: The main outcome measures were 4-year changes in systolic and diastolic blood pressures and the 4-year incidence of high blood pressure in persons not hypertensive at baseline. RESULTS: At baseline, the average systolic and diastolic blood pressures were higher for Beijing than for Guangzhou cohorts. At resurvey the average systolic blood pressure had increased for seven of eight sex-city-setting cohorts (all but Guangzhou urban men). The Beijing urban cohorts had the greatest increases (men 6.2 mmHg, women 4.9 mmHg, slopes of 1.6 and 1.2 mmHg/year). The incidence of high blood pressure was higher for Beijing than for Guangzhou cohorts in all four comparisons (men and women, urban and rural). Beijing men, urban and rural, had the highest incidence rates (about 21%). In multiple logistic analyses by sex, variables significantly related to 4-year high blood pressure incidence were city, baseline systolic blood pressure and body mass index, change in weight, and, for men, baseline alcohol use and heart rate. CONCLUSION: Modifiable lifestyle traits, previously shown to be related to blood pressure and high blood pressure in cross-sectional studies, also relate to the incidence of hypertension.

Adult↗
PubMed1996

[Effects of smoking on lung function in populations of Beijing and Guangzhou].

OBJECTIVE: To analyse the relationship between cigarette smoking and lung function in populations of Beijing and Guangzhou. METHODS: Complete lung function and smoking habit data were recruited from 7983 men and women aged 35-59 in or around Beijing and Guangzhou. Comparisons were made between smokers and never smokers. RESULTS: The mean values of FEV1/H2, FEF/H2 and FEV1/FVC are all lower in smokers than in never smokers for male smokers, the observed mean value of FEV1/H2 for each age group in smaller than the respective predicted value, and its descending trend with aging is more obvious than the predicted value when re-examination after 2-4 years; furthermore, smokers had higher prevalences of respiratory symptom and COPD. CONCLUSION: Cigarette smoking is harmful to lung function.

Adult↗
PubMed1995

The relationship between dietary factors and serum lipids in Chinese urban and rural populations of Beijing and Guangzhou. PRC-USA Cardiovascular and Cardiopulmonary Research Group.

BACKGROUND: Serum cholesterol (TC) levels and coronary heart disease (CHD) are lower in China than in western countries. This report examines the role of diet in determining TC. METHODS: Data were collected as part of a cross-sectional study of 10,000 men and women, 35-54 years old, conducted in 1983-1984 in four areas in China. A 10% subsample was surveyed for eating patterns and measurement of blood lipids. Six one-day dietary recalls were collected on each participant. RESULTS: Mean daily intake of energy from fat was less than 30%. Mean Keys scores ranged from 20.4 to 32.6. In multivariable regression analysis controlling for age, body mass index (BMI), and alcohol, Keys score was statistically associated with serum TC. A 10-unit greater Keys score was associated with 6.3 mg/dl higher TC and 4.0 mg/dl higher low density lipoprotein cholesterol. CONCLUSIONS: We conclude that in China the relation of dietary factors to serum lipids is similar to that in populations having high serum TC levels.

Adult↗
PubMed1994

Body mass, fat distribution and cardiovascular risk factors in a lean population of south China.

The associations of body mass index and abdominal adiposity, represented by an elevated waist/hip circumference ratio, with cardiovascular risk factors were examined in men and women, aged 28-69 years, from urban and rural areas of Guangzhou, China. Mean body mass index ranged from 20.1 to 21.9 kg/m2 across the four sex- and area-groups. Mean waist/hip ratio was 0.84 in men and 0.80 in women. After accounting for age and body mass index, waist/hip ratio was associated negatively (p < 0.05) with fasting serum HDL cholesterol (both sexes), and positively with serum triglycerides (both sexes), total and LDL cholesterol (men only), uric acid (both sexes), glucose (women only), and mean systolic blood pressure (women only). Body mass index was associated in a similar direction with most of these risk factors. These data confirm that abdominal adiposity is independently associated with cardiovascular disease risk factors, even in a lean Asian population.

Abdomen↗
PubMed1994

A north-south comparison of blood pressure and factors related to blood pressure in the People's Republic of China: a report from the PRC-USA Collaborative Study of Cardiovascular Epidemiology.

OBJECTIVES: To compare blood pressures in northern (Beijing) and southern (Guangzhou) Chinese population samples aged 35-54 years, males and females, urban and rural, and to assess the role of blood pressure-related traits in explaining north-south differences. DESIGN: Cross-sectional surveys were conducted in 1983-1984 of northern and southern populations employed in industry (urban) or farming (rural). METHODS: In the north samples were selected from the Capital Iron and Steel Complex (urban) and Shijingshan district (rural); in the south samples from the Guangzhou Shipyard (urban) and Panyu County (rural) were used. RESULTS: The number of subjects surveyed in north and south were 4706 and 4179, respectively: 1500 and 1052 urban males, and 717 and 914 rural males; and 1300 and 1061 urban females, and 1189 and 1152 rural females, respectively. Average systolic (SBP) and diastolic (DBP) blood pressures, were consistently higher in the north than in the south. SBP and DBP were significantly and independently related to age, body mass index, heart rate, use of antihypertensive drugs, serum triglycerides level, alcohol use (males only) and inversely to cigarette smoking. Northerners were older, taller, heavier and had higher body mass index and triglycerides level than southerners. With adjustment of SBP and DBP for blood pressure-related traits, north-south blood pressure differences decreased, but remained significant for urban males, rural males and rural females, with sizeable differences for rural samples in particular. CONCLUSIONS: North-south differences in blood pressure in these samples are accounted for only partly by north-south differences in the cited blood pressure-related traits. The role of other traits requires assessment.

Adult↗
PubMed1993

A novel combinational pH-PCO2 microelectrode.

A novel combinational pH-PCO2 microelectrode based on a neutral carrier hydrogen ion exchanger is described. It is easy to fabricate and allows pH and PCO2 to be measured simultaneously. The microelectrode has a 5-microns tip. The PCO2 microelectrode exhibits a linear response in the range 1.75 x 10(-5)-10(-2) mol/liter with a Nernstian slope of 57.0 mV/decade at 25 degrees C. The detection limit is 10(-5) mol/liter. The pH microelectrode exhibits a linear response in the range pH 4-12 with a Nernstian slope of 60.0 mV/decade at 25 degrees C. The 95% steady-state response time of the PCO2 microelectrode is about 2 min, while it is about 10 s for pH microelectrode. The electromotive force drift is 4.3 mV/h (PCO2) and 2.6 mV/h (pH), respectively. The lifetime is 3 to 4 days. The microelectrode can measure pH and PCO2 in body fluids simultaneously with satisfactory results. It is also a good basic electrode for enzyme microelectrolysis.

Animals↗
PubMedDate not supplied

GC/ITMS measurement of carbonyls and multifunctional carbonyls in PM2.5 particles emitted from motor vehicles.

A method was developed and tested to identify and quantitate carbonyls and multifunctional carbonyls in fine particulate matter (PM2.5; <2.5 microm aerodynamic diameter). The method relies on ultrasonic extraction of particulate matter on filters at -8 degrees C; derivatization with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA), and PFBHA along with bis (trimethylsilyl) trifluoroacetamide (BSTFA); and detection of the derivatives by gas chromatography/ion trap mass spectrometry. Ultrasonic extraction of model compounds from enriched particles was affected by solvent polarity (water > methylene chloride > toluene-isopropanol (2 + 1, v/v). Water provided the highest recovery for dihydroxy acetone, pyruvic acid, and hydroxy acetone, compared to methylene chloride, and toluene-isopropanol. Lowering the ultrasonication bath temperature from 0 degrees to -8 degrees C improved the recoveries of the less water soluble and more volatile species-methacrolein, methyl vinyl ketone, 2,3-butanedione, and tolualdehyde. The power of the method was demonstrated by identification and quantitation of carbonyls and multifunctional carbonyls in sample extracts of fine particulate matter (PM2.5) collected in the Caldecott tunnel, CA. The identities of crotonaldehyde, 2,3-butanedione, glyoxal, 9H-fluoren-9-one, glycolaldehyde, glyoxylic acid, levulinic acid, and 3-hydroxybenzaldehyde were confirmed by comparing the relative retention time and mass spectra of the analyte in the sample extract with an authentic standard. Quantitation of crotonaldehyde, glyoxal, 2,3-butanedione, glyoxylic acid, and levulinic acid was accomplished. This is the first report of glyoxylic acid, levulinic acid, and 3-hydroxybenzaldheyde in PM2.5 particles sampled in a roadway tunnel. It is also the first report of a C10 carbonyl with the molecular formula of C10H16O2, a hydroxy carbonyl with the molecular formula of C17H21NO2, and a hydroxy or dihydroxy carbonyl with the molecular formula of C16H14O2 or C9H10O3. The high-molecular weight hydroxy carbonyls, which were found only in the heavy-duty (diesel) bore, may be tracers of diesel emissions in air.

Air Pollutants↗