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Biomedical subjects

M Q Wang

Publications and source records attributed to M Q Wang.

At least 73 records · Page 4Linked to original sources

Effects of extracorporeal circulation on blood ketone body ratio reflecting hepatic energy metabolism during cardiac operation.

To examine the effects of extracorporeal circulation using an artificial heart and lung machine on hepatic energy metabolism in patients with cardiac operation using hypothermia, the arterial blood ketone body ratio (AKBR) reflecting the hepatic mitochondrial redox state was determined in 12 patients who had undergone cardiac operation using extracorporeal circulation from March to August 1991. Changes in AKBR were compared with those before and after extracorporeal circulation. AKBR decreased significantly after the beginning of extracorporeal circulation (p < 0.001) and remained at a lower level throughout extracorporeal circulation. On termination of extracorporeal circulation, the initial level was immediately resumed. The extent of decrease in ketone body ratio at ten minutes before termination of extracorporeal circulation was correlated with short term postoperative hepatic insufficiency. The patients whose ratio decreased below 0.4 showed increased levels in glutamic-pyruvic transaminase at the end of the first and second week after operation. Changes in AKBR were significantly associated with those in blood pressure (r = 0.433; p < 0.005) and body temperature (r = 0.472; p < 0.005). It was concluded that blood pressure and body temperature influence the blood ketone body ratio during extracorporeal circulation.

Adolescent↗

Acute alcohol intoxication, body composition, and pharmacokinetics.

The present study compared alcohol pharmacokinetics associated with body weight, anthropometrically estimated total body water, and body mass index in men and women in two experimental sessions, single dose and double dose. All subjects were given the same amount of alcohol (2.3 and 4.6 oz. 86 proof vodka for single dose and double dose, respectively). Data analyses found a significant correlation between body mass index and peak blood alcohol concentration (BAC). Weight and total body water were not significantly correlated with peak BAC. The findings suggested that body mass index may be considered a better criterion than body weight for equating alcohol doses.

Adult↗

Predicting alcohol impairment: perceived intoxication versus BAC.

The purpose of this study was to report the relationship among perceived intoxication, performance impairment, and actual blood alcohol concentration (BAC) levels. Fifteen subjects, aged 21 to 40, completed both single- and double-dose sessions of alcohol consumption. BACs, reaction and anticipation time, and perceived intoxication data were collected during both sessions. Analysis of data showed that perceived intoxication was significantly related to performance impairment, but the actual BAC was not.

Adult↗

Psychomotor and visual performance under the time-course effect of alcohol.

This study examined reaction time (RT), anticipation time (AT), and visual performance under the influence of blood alcohol concentration (BAC), using a repeated-measures design. Subjects (8 men and 8 women), 21 to 40 yr. of age, participated in both single- and double-dose sessions, in which they drank approximately 2.3 oz. and 4.6 oz. of 86-proof vodka, respectively. The breath BAC was measured at 5-min. intervals. The RT, AT, and visual performance were tested every 20 min. for 140 min. in both sessions. In general, results indicated that RT, AT, and stereoscopic vision were impaired more in the rising BAC curve than the falling BAC curve. In addition, the impairment tended to be greater for the double-dose than the single-dose session. The far and near visual acuities were not affected by the BAC.

Adult↗

[Preliminary study on RFLPs for dystrophin gene in Chinese].

We have studied the RFLPs distribution and frequency of dystrophin gene in Chinese by using 14 subclones of complete 14 kb cDNA for the dystrophin gene as hybridization probes. Allelic fragments are detected in hybridization patterns of Pvu II/1a, Taq I/2b-3, Taq I/5b-7, Xba I/10. Among them, the allelic fragments (26 kb and 3.8 kb) in Pvu II/2b-3 patterns and the allelic fragments (10 kb and 8.4 kb) in Taq I/5b-7 patterns are the new RFLPs which have never been reported. From the comparison of our data with those of Caucasian and Japanese respectively and their statistical analysis, we can obtain the results as follows: There is remarkable difference (p less than 0.01) of the allelic fragment frequency in Taq I/2 b-3 (A1 = 3.4 kb, fre. 0.04; A2 = 3.2 kb, fre. 0.96) and Xba I/10 (A1 = 7.4 kb, fre. 0.41; A2 = 6.7 kb, fre. 0.59) between Chinese and Caucasian. The frequency of the allelic fragments A2 in Taq I/8 (A1 = 6.5 kb, A2 = 5.6 kb) and EcoR V/9 (A1 = 11.8 kb, A2 = 10.7 kb) are high in Caucasian, but have not been detected in Chinese. These differences are also highly significant. But the B1B2 allelic frequencies in Taq I/5 b-7 (B1 = 3.2 kb, B2 = 1.6 kb) are the same. There is no significant difference in the frequency of the allelic fragments A1A2 and B1B2 in Pvu II/1 a between Chinese and Japanese. Preliminary results suggest that there probably are high frequencies for spontaneous neutral mutations in the evolution process of the huge dystrophin gene (about 2,300 kb). In the meantime, the neutral mutation frequencies of various sectional sequences have remarkable differences, and that of some sectional sequences of the gene between Chinese and Caucasian may also have remarkable differences.

Adult↗

Inaccuracies in self-reported weights and heights of a sample of sixth-grade children.

We collected self-reported weights and heights of 806 sixth-graders in Pennsylvania and compared these values with measures of the children obtained by trained personnel who used standard clinical scales and rigid stadiometers. Approximately 10% of the children either were unable to specify a value for weight, height, or both or reported values of a magnitude indicating that they could not quantitatively conceptualize these measurements. Of the remaining 90%, both boys and girls tended to underreport their weight. Underreporting weight was more pronounced among girls than among boys; for both sexes, the degree of underreporting was much greater among taller, heavier children than among shorter, lighter children. Deviation between self-reported and measured height was substantial for many individuals, but there was no consistent trend toward underreporting or overreporting. These findings indicate that children's self-reported weight data may have a systematic bias, particularly if a large proportion of the sample is over-weight; height data may have considerable random error. We, therefore, conclude that self-reported weights and heights of children may be subject to errors that could confound results if used in clinical or research efforts.

Bias↗

[Immunohistochemical study on distribution of human chorionic gonadotropin (HCG) and placental lactogen (HPL) in trophoblastic tumors].

Preliminary results of observation on the immunohistochemical localization of HCG and HPL are reported, involving totally 15 cases of hydatidiform moles, 17 cases of invasive moles and 15 cases of choriocarcinoma. An intermediate type of trophoblast (IT) was identified in the gestational trophoblastic tumors. The presence of HCG and HPL in both IT and syncytiotrophoblast (ST) varied with the type of trophoblastic tumors. Syncytiotrophoblast sometimes contained both of the hormones, whereas IT contained HPL predominantly. Cytotrophoblasts were devoid of HCG and HPL except in choriocarcinoma.

Chorionic Gonadotropin↗

Comparative study on the evolution of chloroplast ribosomal 5S RNA of a living fossil plant, Cycas revoluta Thumb.

The complete nucleotide sequence of Cycas revoluta Thunb chloroplast 5 S rRNA was determined. It consists of 122 nucleotides. This is the only known 5 S rRNA sequence in Gymnospermae. It is highly homologous with chloroplast 5 S rRNA of higher plants (92-97%), but less homologous (about 54%) with those of lower plants. There is however 67% homology between Cycas and a procaryote a. nidulans. The chloroplast 5 S rRNAs of Angiospermae are nearly identical with each other (95-97%). S. oligorhize and L. minor have 100% homology among themselves. We have constructed a phylogenic tree of 5 S rRNA sequences from fifteen plant chloroplasts. The result suggests that the emergence of algae occurred at an early stage of plant chloroplast evolution and that green plants originated from green algae. This is in agreement with the classical view and other theories of molecular evolution. However there is no common ancestor in the case of Bryophyta and ferns. Among the Angiospermae, a precise evolutionary process cannot be deduced because the Knuc values among the species are very close to each other.

Base Sequence↗

Beta-thalassemia in China: a systematic molecular characterization of beta-thalassemia mutations.

In order to initiate a program of prenatal diagnosis for the prevention of beta-thalassemia in China, we have begun systematic studies of the beta-thalassemia mutations among the Chinese. DNA polymorphisms in the beta-globin gene cluster were examined in 46 beta-thalassemia chromosomes. Six different haplotypes were observed. One beta-thalassemia gene associated with a new haplotype was cloned and sequenced. The mutation was a single base substitution (A----G) at position -29 within the highly conserved proximal promoter element (the "TATA" box). This mutation was not observed previously in the Chinese. The beta-thalassemia genes were further screened with oligonucleotide probes specific for all known mutations in the Chinese. Five mutations were identified and accounted for 35 beta-thalassemia alleles.

Child↗

Bronchial arteriography and transcatheter embolization in the management of hemoptysis.

PURPOSE: The purpose of this study was to determine the factors influencing the effect of bronchial artery embolization in treating massive hemoptysis and the value of bronchial arteriography in the evaluation of patients with hemoptysis. METHODS: Thirty-five patients with acute hemoptysis were evaluated by means of bronchial arteriography and treated with transcatheter embolization. Specific causes for bleeding were bronchiectasis (17), lung cancer (9), tuberculosis (4), tetralogy of Fallot (1), and idiopathic hemoptysis (4). The materials used for embolization were gelatin sponge in 33 patients, dextran microspheres in 2, and stainless coils in 1. RESULTS: The angiographic signs of hemorrhage encountered were extravasation of contrast media (14.2%), hypervascularization (94.5%), bronchopulmonary shunts (34.2%), and bronchial artery aneurysms (14.2%). Immediate control of bleeding occurred in 32 (91.4%) of 35 patients after embolization. The rate of recurrent hemoptysis was 20.0% after 2 weeks of the procedure, but the hemorrhage was less severe than before treatment. CONCLUSION: The data suggest that bronchial artery embolization is an effective method for managing patients with hemoptysis. Minor bleeding recurrences appear to be relatively frequent.

Acute Disease↗

Diagnosis of an accessory portal vein and its clinical implications for portosystemic shunts.

PURPOSE: To present a peculiar anatomic portal veins variant and evaluate its clinical implications. METHODS: Among 118 consecutive patients undergoing transjugular intrahepatic portosystemic shunting (TIPS), six male patients were found to have an accessory portal vein, which was seen during direct portography.R ESULTS: In all six patients, portograms showed an accessory small-caliber vein parallel to the trunk of the main portal vein ending in the right lobe of the liver. Two of the six accessory portal veins drained blood from coronary veins, precluding access to coronary vein embolization during TIPS. CONCLUSION: An accessory portal vein is a rare anatomical variation with clinical significance for both surgical shunt placement and TIPS, as well as for transportal embolization of coronary veins.

Humans↗

The impact of worksite-based safety belt programs: a review of the literature.

PURPOSE: The purpose of this paper is to provide a literature review of the research that examines the effectiveness of worksite intervention programs designed to increase the use of safety belts by employees. SEARCH METHODS: The literature search, which identified 14 research studies on worksite safety belt programs conducted between 1968 and 1994, originated as part of a larger review on the health impact of worksite health promotion programs that was conducted by the Centers for Disease Control and Prevention (CDC). In addition, the authors conducted an additional search in an effort to validate the CDC search, but found no additional research articles. SUMMARY OF IMPORTANT FINDINGS: The literature specific to the effectiveness of safety belt programs is limited to only 14 studies. The safety belt intervention most commonly evaluated used behavioral modification principles involving incentives. These and other interventions demonstrated effective increases in seat belt utilization that, upon withdrawal of the intervention, achieved a recidivism rate above baseline levels. However, the vast majority of studies failed to incorporate control groups into their research design, which caused significant threats to internal validity. Thus, a summary of findings is only suggestive at best. MAJOR CONCLUSIONS: Based on the literature, there appears to be an insufficient number of quality research studies from which to derive a clear view of the impact of worksite safety belt programs. While the evidence is suggestive of a positive impact on safety belt use, there is a clear need for new, well-designed research initiatives on the effectiveness of theory-based safety belt intervention programs.

Accidents, Traffic↗

Social environmental influences on adolescents' smoking progression.

OBJECTIVE: To determine social environmental factors in relation to adolescent smoking using both longitudinal and cross-sectional analyses. METHODS: A national sample of nonsmoking adolescents (N=4,431) who participated in the 1989 Teenage Attitudes and Practices Survey and who were re-interviewed in 1993 was used for this study. RESULTS: The smoking behavior of best friends and smoking beliefs were consistent and significant factors in predicting adolescents' smoking progression from nonsmoking status to regular smokers or experimental smokers. CONCLUSIONS: By addressing several limitations of previous studies, this paper contributes additional information regarding the adolescents' smoking acquisition process.

Adolescent↗