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Biomedical subjects

T He

Publications and source records attributed to T He.

At least 73 records · Page 4Linked to original sources
PubMed1997

HIV type 1 subtypes, coreceptor usage, and CCR5 polymorphism.

Identification of the chemokine receptors CCR5 and CXCR4 as the major coreceptors for HIV-1 entry has greatly assisted our understanding of HIV-1 pathogenesis, transmission, and tropism. However, most of our current knowledge on coreceptor usage comes from studies using HIV-1 strains or env genes derived from the genetic subtype B predominant in North America and western Europe. In this report, the coreceptor usage of 20 primary viral isolates representative of genetic subtypes A, B, C, D, E, and group O was examined. Thirty-nine full-length CCR5 sequences from individuals of diverse geographic origins were also obtained to examine the possible effect of CCR5 polymorphism on HIV-1 subtype distribution. Our results indicate that (1) CCR5 and CXCR4 serve as the two major coreceptors for viruses belonging to HIV-1 subtypes A, B, C, D, E, and group O, whereas other chemokine receptors such as CCR2b and CCR3 play only a minor role in facilitating viral entry into stimulated PBMCs; (2) the coreceptor usage is determined by the viral phenotype rather than its genotype because all NSI strains, irrespective of their subtype classification, utilize CCR5, whereas all SI strains are able to use CXCR4; and (3) there is no geographic clustering of CCR5 polymorphism in different ethnic populations, suggesting that CCR5 diversity is not the underlying explanation for differences in the spread of different HIV-1 subtypes. Therefore, the uneven worldwide distribution of HIV-1 subtypes is more likely the result of stochastic dissemination.

Amino Acid Sequence↗
PubMed1997

Expectancy of working life of mine workers in Hunan province.

From demographic mortality and disability of, in total, 424965 y from workers in 29 coal or coloured/metal mines in Human province of China during the period 1980-1984, we calculated the length of expected working life (EWL) as well as the life expectancy (EL) of the workers in the different types of mines and between those working on the surface and those working underground. The average life expectancy in the coal mines for those starting work at 15 y was found to be 58.91 y and 49.23 y for surface and underground workers respectively. In the coloured/metal mines they were 60.24 y and 56.55 y respectively. If only the mortality data was taken into account; for the coal mines, the EWL at the age of 15 y of surface workers and underground workers was 48.46 and 45.10 y respectively; whilst in the coloured/metal mines the figures were 48.25 and 45.99 y respectively. If both mortality and morbidity data is used the EWL at the same age and in the same population is for the coal mines 39.42 (surface workers) 25.54 (underground workers) and for the coloured/metal mines 42.05 (surface workers) and 30.02 (underground workers). The main causes of the lowered EWL of the underground workers were industrial accidents and pneumoconiosis which indicates that safety measures need to be increased and working conditions improved to protect underground workers.

Accidents, Occupational↗
PubMed1997

Prevalence of Actinobacillus actinomycetemcomitans serotypes in Japanese patients with periodontitis.

Oral Actinobacillus actinomycetemcomitans strains are serologically classified into 5 distinct groups, a to e. We examined the distribution of A. actinomycetemcomitans serotypes in Japanese patients with periodontitis. A total of 157 A. actinomycetemcomitans clinical isolates from diseased sites of 39 patients with periodontitis were serotyped by using serotype-specific rabbit antisera against A. actinomycetemcomitans serotypes a, b, c, d and e strains. In the immunodiffusion assay, autoclaved extracts of 42, 6, 39, 9 and 41 A. actinomycetemcomitans clinical isolates reacted with serotypes a, b, c, d and e antisera, respectively. Although 37 patients were infected with a serotype strain, 2 patients harbored 2 different serotype strains, b/e and b/untypeable. To establish a correlation between serotype and genotype of A. actinomycetemcomitans clinical isolates from 2 patients who had different serotype strains, we used arbitrarily primed polymerase chain reaction (AP-PCR) to fingerprint clinical isolates of different serotypes. The AP-PCR genotypes among 4 clinical isolates (b/e and b/untypeable) were identical to that of A. actinomycetemcomitans Y4 (serotype b), indicating the presence of multiple A. actinomycetemcomitans serotypes which are genetically homogeneous in the periodontally diseased sites of patients with periodontitis.

Actinobacillus Infections↗
PubMed1997

[Measurement and clinical significance of inspiratory drive efficacy in patients with chronic obstructive pulmonary disease].

To study the relationship between VT/P0.1 and the function of inspiratory muscles, we performed the measurement of VT/P0.1 (inspiratory drive efficacy), MIP (maximal inspiratory mouth pressure) and MMIF (maximal midinspiratory flow) in 15 normal subjects and 60 patients with chronic obstructive pulmonary disease(COPD). The results indicated that VT/P0.1 decreased with the deterioration of COPD and it correlated highly and positively with MIP and MMIF. These suggest that VT/P0.1 can reflect the function of inspiratory muscles as well as MIP and MMIF can.

Aged↗
PubMed1997

[Effect of methylphenidatum on inspiratory muscles function in patients with chronic obstructive pulmonary disease and its mechanism].

To have a better understanding of the effect of methylphenidatum on inspiratory muscles function, we studied the respiratory force parameters of 70 patients with chronic obstructive pulmonary disease by intravenous infusion methylphenidatum in a randomized controlled clinical trial. The indices of respiratory force parameter included maximal inspiratory mouth pressure (MIP), maximal midinspiratory flow (MMIF), forced inspiratory capacity (FIC), maximal works of inspiration (Wimax) and airway occlusion pressure (P0.1), etc. Aminophylline and Nikethamidi were chosen as controls. The results showed that MIP, MMIF, FIC, Wimax, P0.1 and minute ventilation (Vr) were significantly increased after administration of methylphenidatum and aminophylline. There were no significant differences in MIP, MMIF, FIC and Wimax after administration of Nikethamidi, but P0.1 was significantly increased and the increase was higher than that after administration of methylphenidatum and aminophylline groups. We conclude that methylphenidatum can significantly improve the function of inspiratory muscles as aminophylline can do.

Female↗
PubMed1997

[Measuring EEG complexity for studying the state of mental load].

The complexity defined by Lemple and Ziv (1976) represents the degree of the sequence randomness. In this paper, the complexity of EEG under different mental loads was measured and the relation between the brain active state and the EEG complexity was analyzed. The results showed a statistically strong relation between the mental load and the EEG complexity. Further study showed that the heavier the mental load was the smaller the EEG complexity became. This correlation was especially apparent in the frontal lobe, and the complexity of EEG might be regarded as one of the parameters representing the functional state of the brain. The results indicate that EEG complexity represents the active state of brain in processing information, and the measurement of EEG complexity may provide a new path to the research in the advanced cognitive function of the human brain.

Adult↗
PubMed1996

Clinical results of computerized tomography-based simulation with laser patient marking.

PURPOSE: Accuracy of a patient treatment portal marking device and computerized tomography (CT) simulation have been clinically tested. METHODS AND MATERIALS: A CT-based simulator has been assembled based on a commercial CT scanner. This includes visualization software and a computer-controlled laser drawing device. This laser drawing device is used to transfer the setup, central axis, and/or radiation portals from the CT simulator to the patient for appropriate patient skin marking. A protocol for clinical testing is reported. Twenty-five prospectively, sequentially accessioned patients have been analyzed. RESULTS: The simulation process can be completed in an average time of 62 min. Under many cases, the treatment portals can be designed and the patient marked in one session. Mechanical accuracy of the system was found to be within +/- 1mm. The portal projection accuracy in clinical cases is observed to be better than +/- 1.2 mm. Operating costs are equivalent to the conventional simulation process it replaces. CONCLUSION: Computed tomography simulation is a clinical accurate substitute for conventional simulation when used with an appropriate patient marking system and digitally reconstructed radiographs. Personnel time spent in CT simulation is equivalent to time in conventional simulation.

Computer Simulation↗
PubMed1996

The role of a mutant CCR5 allele in HIV-1 transmission and disease progression.

A 32-nucleotide deletion (delta 32) within the beta-chemokine receptor 5 (CCR5) gene has been described in subjects who remain uninfected despite extensive exposure to HIV-1. This allele was found to be common in the Caucasian population with a frequency of 0.0808, but was not found in people of African or Asian ancestry. To determine its role in HIV-1 transmission and disease progression, we analyzed the CCRS genotype of 1252 homosexual men enrolled in the Chicago component of the Multicenter AIDS Cohort Study (MACS). No infected participant was found to be homozygous for the delta 32 allele, whereas 3.6% of at-risk but uninfected Caucasian participants were homozygous, showing the highly protective role of this genotype against sexual acquisition of HIV-1. No evidence was found to suggest that heterozygotes were protected against HIV-1 infection, but a limited protective role against disease progression was noted. The delta 32 allele of CCR5 is therefore an important host factor in HIV-1 transmission and pathogenesis.

Alleles↗
PubMed1996

Nutritional analysis and an enriched medium for fermentative treponemes isolated from subgingival plaque.

In order to cultivate fermentative treponemes isolated on Medium 10 with the plate-in-bottle method from subgingival plaque, we developed the enriched Medium 10. Enriched Medium 10 broth consisted mainly of Trypticase peptone (2 g/L), yeast extract (10 g/l), glucose (5 g/l) and volatile fatty acids mixture (3.1 ml/l). The growth curves in enriched Medium 10 broth showed that clinical isolates of Treponema socranskii reached the early stationary phase on the 3rd-5th day, and the doubling times averaged 22.2h. By using enriched Medium 10, the nutritional analysis of oral treponemes was examined for each compound of the volatile fatty acid and various sera. Clinical isolates were found to require iso-butyric acid, 2-methylbutyric acids and/or iso-caproic acid independently for their growth. However, the growth of these fermentative treponemes was inhibited by addition of various sera to this medium.

Animals↗
PubMed1996

Microbial flora in the acute phase of periodontitis and the effect of local administration of minocycline.

Periodontitis, similar to other infectious diseases, is known to progress as chronic inflammation with recurrent acute phases. The purpose of this study was to clarify the microbiological composition of the acute phase and to compare the bacterial flora with that of comparable chronic periodontal pockets. We also evaluated the effect of application of minocycline gel locally on the change in the microflora in the acute pockets. Microbial flora from the subgingival pockets of 28 patients in the acute phase of periodontitis and of 12 patients in a comparable chronic phase as the control were investigated by various bacterial culture methods including TS blood agar and TSBV plates. Minocycline gel was applied to the acute periodontal pockets. Changes in the microbiological proportion and clinical parameters at one week after baseline examination were followed by dark-field analysis, culture method, and indirect immunofluorescence technique. Characteristic features of bacterial proportions in the acute site were observed as an increase in Bacteroides forsythus. The number of Porphyromonas gingivalis and black pigmented anaerobic rods also increased. Application of minocycline gel in the acute pocket without any debridement produced improvement in clinical symptoms at one week. Black-pigmented anaerobic rods, P. gingivalis, and B. forsythus decreased significantly at one week after the application. Results indicate that periodontopathic bacteria including B. forsythus and P. gingivalis were predominant in the acute phase of periodontitis and a locally delivered antibiotic may be effective as an alternative modality of treating the acute inflammation.

Acute Disease↗
PubMed1996

[Evaluation of non radioactive DNA probe (Affirm DP) for detecting periodontopathic bacteria].

The purpose of this investigation was to evaluate the potential of application of non-radioactive DNA probe method (Affirm DP) in clinical diagnosis and evaluation of treatment efficacy. Sensitivity and specificity of two different cut-off levels (10(4), 5 x 10(5)) of the method with bacterial culture in detection of Bacteroides forsythus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans were compared. Those bacteria were obtained from bacterial cultures and clinical samples from healthy subjects and patients with periodontal disease. The results showed that detection percentage of DNA probe method with 10(4) cut-off was equal to or higher than the culture method for Bacteroides forsythus and Porphyromonas gingivalis detection. Therefore, it is suggested to be a useful chairside DNA probe kit as an aid in clinical diagnosis and evaluation of treatment efficacy.

Aggregatibacter actinomycetemcomitans↗
PubMed1996

[Measurement of maximal inspiratory flow and forced inspiratory capacity and its clinical application].

The methods of measuring the maximal inspiratory flow (V(imax)) and the forced inspiratory capacity (FIC) via forced inspiratory capacity-time curve (FIC-t curve) were investigated. Both V(imax) and FIC were measured in 35 normal subjects and 89 patients with chronic obstructive pulmonary disease (COPD). The maximal inspiratory pressure (MIP) was measured simultaneously at function residual capacity(FRC) level by modified Black Method. The results showed that there is a linear relationship between MIP and V(imax) or FIC in both normal subjects and patients with COPD. Normal subjects had a mean V(imax) and FIC much higher than those of patients with COPD. The values of V(imax) and FIC in patients were also, significantly correlated to the severity of COPD. So we suggest that both V(imax) and FIC be used as clinical indices to reflect inspiratory muscles strength.

Adult↗
PubMed1996

[Cetirizine improves the resistance of airway and pulmonary function in patients with asthma].

The objective of this study was to investigate the possible anti-asthma role of Cetirizine. Forty asthmatics were randomly divided into two groups. The experimental group had 30 patients. Among them were 10 patients with simple asthma, 5 patients complicated by mild emphysema, 6 patients complicated by moderate emphysema and 9 patients complicated by severe emphysema. Vit-C (control) group had 10 cases, including 2 cases of simple asthma, 6 cases complicated by mild emphysema and 2 cases complicated by moderate emphysema. All patients had a single oral dose of 5 mg Cetirizine or 0.1 g Vit-C blindly. Before and 0.5, 1 hour after their medicines, the resistance of airway (Raw), sGaw and MEFV were examined in all patients on 6200 Plethysmograph. The measured values showed a significant improvement of Raw and sGaw after administration of Cetirizine. In half an hour after Cetirizine, the Raw decreased by 20.408%, and sGaw increased by 28.249%. In one hour after Cetirizine, Raw further decreased by 24.34% and sGaw increased by 41.153% (P < 0.001). The FVC in MEFV increased by 4.96% (P < 0.02) in one hour after Cetirizine, but other parameters in MEFV curve (PEF, FEV1, MMEF) had no significant changes. All parameters in control group had no significant changes (P > 0.05). The results indicate that Cetirizine could decrease Raw in asthmatics, improve their lung ventilatory function. Cetirizine is a new H-receptor antagonist usually used as anti-inflammatory and allergy suppression medication. It is shown that Cetirizine is a promising anti-asthma agent in treating bronchial asthma.

Adult↗
PubMed1996

[Diagnostic value of exercise diffusion capacity test on diffuse pulmonary fibrosis].

Diffusion capacity for carbon monoxide of the lung (DLCO) before-and-after exercise test and 5 routine pulmonary function tests were conducted in 16 patients with diffuse pulmonary fibrosis (DPF), 19 patients with interstitial pneumonia (IP), 17 patients with COPD, and 22 normal subjects. The data showed: in normal subjects the DLCO after exercise increased significantly compared with before (P < 0.001). But in DPF group the DLCO before exercise was below the normal range, and it went down further after exercise, the decreasing rate being 17.95% (P < 0.001). The DLCO in IP and COPD groups did not significantly change before and after the exercise. Two cases of interstitial pneumonia, who had a reduced DLCO after exercise, were followed up for 0.5-1.0 year, and both patients developed into DPF by that time. The results suggest that the DLCO measure before and after exercise test may have important value for DPF diagnosis, and a reduced DLCO after exercise test in IP patients may warn the development from IP into DPF.

Adult↗
PubMed1996

[Value of measuring resistance of airway for diagnosis of asthma].

Resistance of airway (Raw), sGaw and Maximal expiratory flowvolume curve (MEFV) were measured in 35 normal subject, 43 patients with remission asthma and 100 patients with remission chronic bronchitis (some complicated by obstructive emphysema). The measured values showed that in simple asthma Raw was significantly higher than that in normal subject and in patients with chronic obstructive bronchitis (COB), but MEFV was in normal range. In chronic bronchitis the value of Raw was higher than that in normal subject, but lower than that in asthma (0.05 > P > 0.02); however the FEV1, MMEF, V75 in the curve of MEFV were significantly decreased at the stage of COB, with the most remarkable decrease in MMEF. The results suggest that Raw is a sentitive test for diagnosis of simple asthma, in addition to MEFV measurement; it may be helpful for differential diagnosis of simple asthma and COB and may has potential value for clinical practice.

Adult↗
PubMed1995

Evaluation of changes in the size and location of the prostate, seminal vesicles, bladder, and rectum during a course of external beam radiation therapy.

PURPOSE: To document the size and location of the prostate, seminal vesicles, bladder, and rectum throughout the course of external beam radiotherapy. The frequency and range of motion of these organs are quantified. METHODS AND MATERIALS: Ten patients with localized carcinoma of the prostate had conventional simulation followed immediately by a treatment planning computed tomography scan (TPCT0). Once treatment was initiated, each patient had a weekly CT (TPCT1-N) before or after his daily treatment. Anatomical structures from CT were delineated on a computer workstation for analysis. The serial CT sets were spatially registered to the initial scan using image correlation software that brings into congruence the bony pelvis of the different scans. The location of the prostate, seminal vesicles, bladder, and rectum on subsequent scans were compared to TPCT0, as well as to each other. RESULTS: Prostate volumes were observed to vary by an average of +/- 10% during the course of radiation therapy, while the seminal vesicle volumes varied by as much as 100%. Bladder and rectal volumes varied by +/- 30%. Compared to TPCT0, movement of the prostate was demonstrated in all patients. Quantitation of the center-of-mass (CM) showed motion of less than 1 mm in the left-right direction, while motion ranging from 0 to +/- 1 cm was observed in the anterior-posterior and superior-inferior directions. The individual standard deviations of these motions varied from approximately 1-5 mm. These variations were correlated to changes in the dimensions of the bladder and rectum. CONCLUSIONS: Changes in the location of the prostate, seminal vesicles, and normal tissue volumes during the course of radiation therapy occur and have dosimetric consequences that may impact tumor control and normal tissue complication probabilities. Conformal therapy for prostate cancer will require the incorporation of knowledge of the anatomic relationships of these structures as a function of time. Therefore, these uncertainties must be taken into account when designing treatment plans and in considering dose escalation trials.

Humans↗