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Biomedical subjects

X Hu

Publications and source records attributed to X Hu.

At least 487 records · Page 27Linked to original sources
PubMed1992

The physical, psychological, and socioeconomic costs of pediatric trauma.

This prospective study examined the physical, psychological, and socioeconomic effects of injuries on children and their immediate families. Ninety-two injured children admitted with minor (ISS less than 16) or major (ISS greater than or equal to 16) injuries were compared with a control group of 59 children admitted during the same period with acute appendicitis. The two populations were similar in mean age, sex ratio, parental age and work status, and number of siblings. The parents of the injured children had a lower level of education than those of the controls. Fifty-four percent of the minor injury patients and 71% of the major injury patients had persistent physical limitations at 12 months in contrast to none of the controls. Thirty-eight percent of minor injury patients had pre-existing behavioral disturbances compared with 14% of major injury patients and 10% of controls. Behavioral disturbances among major trauma patients showed a sharp rise to 41% at 12 months and tended to persist in cases with continuing physical limitations. The major injury patients and those with significant head injuries exhibited a decrease in academic performance; minor injury patients and those without head injury showed no change. Maternal malaise rose sharply to about 40% in both injury groups in contrast to 7% in the controls and was more common in the presence of persistent physical limitations. Only 73% of families in the major injury group had returned to normal family life compared with 87% of the minor injury group and 100% of controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Achievement↗
PubMed1992

Clonal and antigenic analysis of serogroup A Neisseria meningitidis with particular reference to epidemiological features of epidemic meningitis in the People's Republic of China.

Representative strains of serogroup A Neisseria meningitidis were chosen from all major meningitis epidemics worldwide since 1960 and subjected to analysis for the electrophoretic variation of 15 cytoplasmic allozymes and four outer membrane proteins. The 290 strains defined 84 unique electrophoretic types which were classified in nine subgroups. Tests with monoclonal antibodies specific for conserved pilin epitopes showed that the class I, IIa, and IIb epitopes were uniform within the subgroups. Similarly, the subgroups were uniform for expression of different variable regions of class 1 outer membrane protein, with a few minor exceptions. Many of the bacteria tested were isolated in the People's Republic of China, and the epidemiology of Chinese epidemics of meningococcal meningitis is described. The analysis approaches a global description of epidemic meningitis caused by serogroup A meningococci in the past 30 years.

Animals↗
PubMed1992

Dose related acute irritant symptom responses to occupational exposure to sodium borate dusts.

A repeated measurement design was employed in the study of acute symptoms of eye and respiratory tract irritation resulting from occupational exposure to sodium borate dusts. The symptom assessment of the 79 exposed and 27 unexposed subjects comprised interviews before the shift began and then at regular hourly intervals for the next six hours of the shift, four days in a row. Exposures were monitored concurrently with a personal real time aerosol monitor. Two different exposure profiles, a daily average and short term (15 minute) average, were used in the analysis. Exposure-response relations were evaluated by linking incidence rates for each symptom with categories of exposure. Acute incidence rates for nasal, eye, and throat irritation, and coughing and breathlessness were found to be associated with increased exposure levels of both exposure indices. Steeper exposure-response slopes were seen when short term exposure concentrations were used. Results from multivariate logistic regression analysis suggest that current smokers tended to be less sensitive to the exposure to airborne sodium borate dust. There was no indication that anhydrous sodium borate was more potent than the other sodium borates in this work environment.

Adult↗
PubMed1992

Computerized plotting of low skin impedance points.

The distribution of low skin impedance points (LSIP) was studied on 68 subjects with a computer system designed for the measurement of skin impedance. The results demonstrated that LSIPs were basically distributed along the 14 channels, the overwhelming majority located right on or within 5 mm bilaterally to their courses. LSIPs were found in the area between every two channels only in a few cases. Moreover, there was no marked natural fluctuation of skin impedance in the human body and the distribution of LSIPs was considerably stable, which could be plotted on any day in the experiment. It is clear that such particular distribution of LSIPs along channels was really a biological phenomenon, not an experimental error. However, the distribution of low skin impedance was not an uninterrupted solid line but a series of LSIPs basically along the channel course. The method used in this work was accurate, reliable and repeatable which has upgraded the measurement of LSIPs to a new level. Under certain conditions, skin impedance can be used as an objective index in channel research.

Adult↗
PubMed1992

[Pharmacokinetics of liensinine in rabbits].

A method for the determination of plasma concentration of liensinine with HPLC and pharmacokinetic study of liensinine in rabbits were reported. Assay linearity was shown over the range of 0.125-2.5 micrograms/ml serum with regression coefficient of 0.9997. The mean recoveries of liensinine in plasma (within-day and between-days) were all more than 99% of the dose and the coefficients of variation were less than 5%. After a single intravenous injection of liensinine 6mg/kg to rabbit. The pharmacokinetic characteristics were found to fit a two-compartment open model. Important parameters were: t1/2 alpha = 8.303 min t1/2 beta = 129.960min AUC = 132.67 micrograms.min/ml CL = 0.045 L/min Vc = 2.768 L/kg.

Animals↗
PubMed1992

Detection of circulating antigen by McAb-AST for evaluating the efficacy of anti-Leishmania chemotherapy.

We have adapted the simple and sensitive McAb-antigen spot test (AST) for evaluating the efficacy of anti-Leishmania chemotherapy. Serum samples from 37 kala-azar patients were tested by McAb-AST, and all showed definite positive reactions before treatment. After a course of antimony treatment, 20 turned negative, coupled with the disappearance of clinical symptoms; another 12 cases responded with weak positivity accompanied by an improvement of clinical manifestations; and the remaining 5 antimony-resistant patients showed strong positive reactions, with their conditions gradually worsening. Furthermore, all 6 cases in which the diagnosis was missed by the bone marrow smear method turned McAb-AST negative after chemotherapy. These results suggest that McAb-AST can be used to evaluate the efficacy of chemotherapy as well as to avoid missed diagnosis by the bone marrow smear method.

Adolescent↗
PubMed1992

[Identification of morphology and inorganic elements of Eucommia ulmoides Oliv. produced in Sichuan by applying scanning electron microscope with energy dispersive X-ray analysis].

A research on the identification of morphology and inorganic elements of Eucommia ulmoides produced in Sichuan has been made by applying scanning electron microscope; energy dispersive X-ray analysis. Qualitative and semi-quantitative analyses of the inorganic elements in the observed areas have been obtained.

Calcium↗
PubMed1992

The quantitative alteration of 5s rRNA during the development of mammalian erythroid cells and its effect on DNA synthesis in SP2/0 mouse myeloma cells.

Mouse myeloma cells (SP2/0) were incubated with 125I-5s rRNA from rabbit reticulocytes and processed for autoradiography. The results indicated that 5s rRNA could pass into the nuclei of mouse myeloma cells. In a separate experiment, SP2/0 were incubated with cold 5s rRNA, then with 3H-TdR and processed for autoradiography. It was found that in the mouse myeloma cells, DNA synthesis and cell division were obviously suppressed. In another series of experiments, rRNA was extracted from rabbit bone marrow, reticulocytes and erythroid cells and from rat embryonic liver and erythroid cells. The rRNA was analyzed by agarose electrophoresis. It was found that the amount of 5s rRNA in various stages of erythroid development changed along with the denucleating process. Thus it seems likely that 5s rRNA from mammalian erythroid cells could play a role in reversing the malignant phenotype of tumor cells and denucleation of mammalian erythroid cells through inhibiting DNA synthesis.

Animals↗
PubMed1992

Identification of Leishmania donovani isolates from different kala-azar foci in China by kDNA hybridization.

kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization.

Animals↗
PubMed1991

An epidemiologic approach to the study of acute reversible health effects in the workplace.

We present an epidemiologic approach for the study of the irritant effects of sodium borate exposure that can be used to study acute reversible health effects more generally. Acute irritant responses, such as symptoms of nasal irritation or cough, are subjective. They may, however, be accompanied by transient airway obstruction, which can be objectively measured by a change in peak expiratory flow (PEF) or forced expiratory volume in one second (FEV1). Because these physiologic responses are reversible and follow short-term peaks of exposure, they cannot be studied effectively using conventional epidemiologic methods of design and analysis. The proposed study design is a short-term prospective cohort study with frequently repeated measures of health effects and simultaneous measures of exposure. Because each subject passes through periods of high and low short-term exposure, the study has the form of a crossover design. This design permits each acute response to be linked to the corresponding short-term average exposure, providing the data necessary for dose-response analyses within subject. We present the results of the sodium borate study to illustrate the analysis of such data.

Acute Disease↗
PubMed1991

[Alkaloids of plumula Nelumbinis].

Six alkaloids were isolated from the green seed embryo of Nelumbo nucifera growing in Ruichang, Jiangxi province. On the basis of physiochemical properties and spectroscopic methods (UV, IR, NMR, MS) they were identified as: lotusine, nuciferine, pronuciferine, liensinine, isoliensinine and neferine.

Alkaloids↗
PubMed1991

Progress in studies on the antimutagenicity and anticarcinogenicity of green tea epicatechins.

An antioxidative fraction was extracted from green tea and the major compounds in the fraction identified as epicatechins. Experimental results showed that green tea epicatechin compounds (GTEC) inhibited the mutagenicity and/or chromosomal damage caused by different carcinogens in both bacterial and mammalian cells. In vitro, GTEC inhibited transformation of BALB/3T3 cells induced by BP, X-rays, or MCA/TPA. In vivo, green tea extract decreased the incidence of carcinoma in the forestomach and esophagus of mice induced by sarcosine and NaNO2. GTEC inhibited the development of gamma-glutamyl transpeptidase-positive foci in the livers of rats treated with diethyl nitrosamine (DEN) or DEN/phenobarbital. Our investigations indicate that the antimutagenic and anticarcinogenic mechanisms of GTBC are related to the following: increased glutathione-S-transferase activity; inhibition of edema, hyperplasia, and ODC activity induced by TPA; free radical scavenging; blocked tumor promoter-induced inhibition of intercellular communication; and enhanced cell-mediated immunity. GTEC might be useful in the prevention of some kinds of cancer and a variety of oxidation-related diseases.

Animals↗
PubMed1991

[Study on periodically prevalent feature for epidemic cerebrospinal meningitis in China].

A study on periodically prevalent feature for epidemic cerebrospinal meningitis (ECM) in China was carried out by means of cluster analysis of multilocus enzyme electrophoresis, as well as chromosomal DNA fingerprinting and subserotyping of outer membrane protein class 1 of Neisseria meningitidis group A. Two hundred strains tested were isolated from the patients for ECM and carriers during the 1960s to 1980s in 17 provinces and municipalities. Overall analysis on the bacterial types of the strains above mentioned and data of morbidity of this disease for recent 40 years was undertaken. The research results indicated that ECM really possessed the feature of cyclic prevalence in China, the cyclic epidemics were caused by the different predominant types of Neisseria meningitidis group A and the strains of predominant types could be periodically spread. Every epidemic was basically spread from the north to the south of China. However, the patterns of cyclic epidemic of this disease were not uniform in the country. The above study has established the preliminary base to reveal the prevalent mechanism for ECM by use of molecular biological methods in China.

China↗
PubMed1990

Alterations in the electrical properties of T and B lymphocyte membranes induced by mitogenic stimulation. Activation monitored by electro-rotation of single cells.

Stimulation of either B or T lymphocytes using specific mitogens results in changes in the passive electrical properties of the cell surface. These effects can be related to growth and secretion. This was possible because the high resolution of the contra-field electro-rotation method, combined with the use of very low conductivity media, allowed accurate and analytically-derived values for the cell surface properties. Increases in effective CM (membrane capacity) and changes in apparent membrane conductivity (reflecting the additive effects of true membrane conductivity GM and surface conductance KS) were measured. After 72 h treatment with concanavalin A, thymocyte CM had increased from 0.76 muF/cm2 to 1.24-1.46 muF/cm2 (7.6 to 12.4-14.6 mF/m2). Allowing for the stimulation-induced size increase (cell radius increased from 2.8 to 4.4 micron) these data imply that the plasma membrane area per cell increases 5-fold during stimulation. Stimulation of B cells (by 3 days incubation with bacterial lipopolysaccharide) increased CM from 0.93 to 1.6-1.7 muF/cm2 (9.3 to 16-17 mF/m2). Incubation without mitogen gave no significant increase in CM or in radius. Control cells of different sizes showed no difference in membrane properties. The increases in effective CM are argued to reflect an increase in membrane ramification (microvilli, folding, etc.). The apparent membrane conductivity of T cells also increased during stimulation, from 5 to 21 mS/cm2 (50 to 210 S/m2). This increase is proportionately much greater than that in CM or in membrane area. It seems to be due to a real increase in GM, but a small increase in KS may also occur. The earliest changes in apparent membrane conductivity were evident between 3 and 5 h after stimulation, before the cells increased in size. This response parallels increases in transmembrane transport reported to follow mitogenic stimulation.

Animals↗
PubMed1990

[Surveillance of epidemiological features for epidemic cerebrospinal meningitis in China during 1980s].

This paper reports the results of surveillance of epidemiological features for epidemic cerebrospinal meningitis in China during 1980s. Although the incidence of this disease in China in 1984 were up about 50% comparing with in 1983, its morbidities of recent years had been continued to decrease. The patients were distributed rather far apart from one another and the feature of cyclic incidence peak for epidemic cerebrospinal meningitis in 1980s was not obvious as former. However, the possibility which this disease will present prevalence still exists. Because the morbidity would begin to rise again after it decreased to the lowest level. At present, such rising signs have been appeared in some provinces. In addition, Neisseria meningitidis group B isolated from the cases tended to increase. The proportion of cases of young children was increased obviously in comparison with elder children or adults. This status makes the prevention of this disease by using meningococcal polysaccharide vaccine group A some difficulty. The authors also investigated and analysed the effect of normal throat flora of healthy people and other acute respiratory infectious diseases on the epidemic cerebrospinal meningitis.

Adolescent↗
PubMed1990

[Studies on the low skin impedance points and the feature of its distribution along the channels by microcomputer. I. Observation on the reliability of the measurement].

According to the requirement of channel research, a system for the measurement of skin impedance had been designed and a series of experiments to check the reliability of this system had also been done. The facts demonstrated that the pressure exerted by the exploring electrode, the duration of switch-on as well as the number of times of repeated measurements all showed no conspicuous influences on the skin impedance. The results are stable and reliable. Moreover, the measurement and data processing are controlled by microcomputer. Thus, the method of measurement of skin impedance along the channels has been developed to a higher level. Under the conditions of our experiment, the impedance of the low skin impedance points (LSIPs) are about 108k omega, which are quite low than that of the non-LSIPs around them. The difference between the two is highly significant. Both the impedance of LSIPs and non-LSIPs are stable, without marked variation. These results provide the prerequisites indispensable for the further observation on the feature of the distribution of LSIPs.

Acupuncture Points↗