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Biomedical subjects

Q Zeng

Publications and source records attributed to Q Zeng.

At least 127 records · Page 7Linked to original sources
PubMed1997

Calibration inference based on multiple runs of an immunoassay.

Several authors have documented the poor performance of usual large-sample, individual calibration confidence intervals based on a single run of an immunoassay. Inaccuracy of these intervals may be attributed to the paucity of information on model parameters available in a single run. Methods for combining information from multiple runs to estimate assay response variance parameters and to refine characterization of the standard curve for the current run via empirical Bayes techniques have been proposed. We investigate formally the utility of these techniques for improving the quality of routine individual calibration inference.

Bayes Theorem↗
PubMed1997

[A clinicopathological immunohistochemical and cytomorphometric study on midline T cell lymphoma].

One hundred and twenty-two cases of midline malignant reticulosis (MMR) were studied. A series of antibodies including anti-LCA, UCHL-1, L26, CD45R, and anti-lysozyme were used on paraffin sections by ABC and PAP methods. The results were as follows: 112 cases exhibiting T-cell origin, 4 cases showing B-cell origin, and 6 cases being of uncertain lineage. This result is in accordance with the point of view that most of MMR are T cell lymphoma. Two histological types were classified: sarcomatoid type and granulomatoid type. By using image analyzer, the sarcomatoid type was subdivided into small, medium and large cell types. Sixty-two cases with follow-up data were collected for clinicopathologic analysis. One-year and five-year survival rates in cases with different histologic types were compared and statistically analysed. The results showed that the prognosis was closely related to the histological type.

Adolescent↗
PubMed1996

Measuring self-efficacy in people with multiple sclerosis: a validation study.

OBJECTIVE: To assess the psychometric properties of a measure of self-efficacy in people with multiple sclerosis (MS). DESIGN: Cross-sectional study by mail with retest. SETTING: MS Clinic registry of a large Boston teaching hospital . PATIENTS: 141 MS patients representing a broad range of disability. MAIN OUTCOME MEASURES: The MS Self-Efficacy Scale (MSSE), the Expanded Disability Status Scale, the Sickness Impact Profile, and the mastery subscale of the Ryff Happiness Scale. RESULTS: The MSSE has high internal consistency and test-retest reliability, both for the overall scale and for the SE Function and SE Control subscales. Results of convergent and divergent validity analyses suggest that the scale is both sensitive and specific. CONCLUSIONS: We conclude that MSSE is appropriate for assessing self-efficacy in the MS population.

Adult↗
PubMed1996

Psychosocial correlates of fatigue in multiple sclerosis.

OBJECTIVE: To explore: (1) the interrelation among the neuropsychological, psychological, and psychosocial factors and fatigue as measured by the Multidimensional Assessment of Fatigue scale, and (2) the impact of fatigue on role performance. DESIGN: Clinical interview with neuropsychological testing and cross-sectional study by mail. SETTING: Multiple sclerosis (MS) clinic registry of a large Boston teaching hospital. PATIENTS: 139 MS patients representing a broad range of disability. MAIN OUTCOME MEASURES: The Multidimensional Assessment of Fatigue (MAF) scale, the Extended Disability Status Scale, the Sickness Impact Profile, Rao cognitive battery, the Trailmaking Test, depression, anxiety, and social activity limitations subscales from the Arthritis Impact Measurement Scales, and the Ryff Happiness Scale. RESULTS: Stepwise multiple regression analyses revealed that having a low sense of environmental mastery was the best psychosocial predictor of both global fatigue and fatigue-related distress, after adjusting for sociodemographic and medical factors. Further, people who reported being more depressed tended to report more severe fatigue. Neuropsychological performance was not associated with fatigue. Fatigue was found to limit social, work, and overall role performance, but not physical role performance. CONCLUSIONS: People who feel that they can choose or create environments suitable to their psychic or physical conditions report less global fatigue and less fatigue-related distress, and fatigue can have an important impact on role performance. The implications of these findings for designing fatigue management interventions are discussed.

Activities of Daily Living↗
PubMed1996

Retinoic acid normalizes the increased gene transcription rate of TGF-alpha and EGFR in head and neck cancer cell lines.

Retinoic acid (RA) has been shown to be effective in eradicating premalignant lesions and preventing second primary malignancies in patients cured of squamous cell carcinoma of the head and neck (SCCHN) in clinical trials. The basis for this effect is unclear. We have previously demonstrated that messenger RNA from tumor growth factor-alpha (TGF-alpha) and its receptor, the epidermal growth factor (EGFR), is unregulated in tumors and histologically normal mucosal samples from patients with SCCHN compared with control normal mucosa from patients without cancer, implicating this ligand-receptor pair in an autocrine growth pathway early in the molecular pathogenesis of this disease. In this report, we examined the hypothesis that the action of RA on the mucosa of the upper aerodigestive tract is mediated via downregulation of steady-state TGF-alpha and/or EGFR mRNA levels. Following exposure to all-trans-RA, a series of SCCHN cell lines demonstrated a 35.4% reduction in TGF-alpha mRNA expression (P = 0.022) and 58.5% reduction in EGFR mRNA (P = 0.0027). Nuclear run-on analysis indicated that the RA-mediated reduction of TGF-alpha and EGFR steady-state mRNA levels was a result of decreased gene transcription. These results suggest that the clinical effects of RA in SCCHN patients may be due to a downmodulation of TGF-alpha and EGFR mRNA production.

Carcinoma, Squamous Cell↗
PubMed1996

[Combustion under microgravity and technique of fire prevention and suppression in space cabin].

This is a brief review on microgravity combustion, along with the discussion of the fundamental characteristics of combustion and fire processes under microgravity. Recent research activities in microgravity combustion and space fire prevention were emphasized. In addition, the potential use of flame-inhibiting atmospheres in the space cabin was introduced. The technique of fire detection and extinguishment in spacecraft environments was also discussed.

Fire Extinguishing Systems↗
PubMed1996

Mapping medical vocabularies to the Unified Medical Language System.

This paper presents our work in automated mapping of medical vocabularies to the National Library of Medicine's Unified Medical Language System (UMLS). We used the UMLS Knowledge Source (KS) tool to map terms from several sources to UMLS Metathesaurus concepts. We compared performance of the KS tools with our own Minimal Representable Units Method (MRUM). The KS tools were able to map terms from 13% to 54% of the time, depending on the term set and the KS options used. Our MRUM method mapped between 96% and 99% of the terms. Based on our experience, we believe that questions remain about the best method by which the UMLS can be used to achieve automated term translation.

Algorithms↗
PubMed1996

Insect-resistant tobacco plants expressing insect-specific neurotoxin AaIT.

The recombinant plant expression vector pNGY-2 with designed and synthesized AaIT gene had been constructed. The AaIT gene was fused behind the sequence of TMV and inserted into expression vector under the control of two linked 35s promoters. The recombinant plasmid pNGY-2 was transferred into tobacco NC89 by agrobacterium-mediated transfer system. The GUS activity analysis and Southern blotting of regenerated plants indicated that AaIT gene had been integrated into tobacco genome. Insect bioassays showed that some transgenic plants had notable insect-resistant activity.

Animals↗
PubMed1995

An apolipoprotein CIII marker associated with hypertriglyceridemia in Caucasians also confers increased risk in a west Japanese population.

Polymorphisms and haplotypes at the adjacent apolipoprotein (apo) AI and CIII gene loci were investigated in 61 Japanese patients with triglycerides greater than 350 mg/dl and in 66 unrelated normolipidemic subjects. The polymorphic sites were the SstI site in the apoCIII 3' untranslated region, whose presence has previously been shown to be associated with hypertriglyceridemia (HTG) in Caucasians, and the MspI site in the third intron of the apoAI gene. The frequencies of the SstI minor allele (S2) were 0.48 in HTG patients and 0.25 in normolipidemic subjects (P < 0.00015). The frequencies of the MspI minor allele (M2) were 0.61 in HTG patients and 0.33 in normolipidemic subjects (P < 0.00001). The two polymorphic sites were in strong linkage disequilibrium, and maximum likelihood analysis supported the existence of three of the four possible haplotypes: S1-M1, S1-M2, and S2-M2. Since all S2 alleles were estimated to be present on M2-bearing chromosomes, the HTG-associated S2-M2 haplotype conferred the same approximate relative risk as the S2 allele alone when compared with the other two haplotypes (odds ratio 2.8). This study demonstrates that the S2 allele is a marker for HTG among west Japanese subjects as well as among Caucasians. The results suggest that S2-M2 chromosomes carry HTG susceptibility sequences that predate the separation of the Asian and Caucasian races.

Alleles↗
PubMed1995

Keratin 18 is associated with a subset of older taste cells in the rat.

All or nearly all intragemmal (elongated) cells of rat taste buds were immunopositive for keratins 7, 8, and 19. In contrast, keratin 18 was detected in 19 +/- 5 cells per taste bud (mean +/- sd), or about 25% of the intragemmal cells. During taste bud development keratins 7, 8, and 19 were evident initially in polygonal cells and later in elongated taste cells. Keratin 8 appeared in vallate taste cells at P0 (postnatal day 0), followed by keratins 7 and 19 at P1, and keratin 18 at P2-P3. Keratin 18 was always limited to elongated cells. The assemblage of elongated taste cells comprising a taste bud began with a single elongated cell, rather than with the synchronous elongation of a cluster of cells. Developmental errors were observed at P2-P3, e.g., some vallate taste cells had a misoriented axis. In order to study the pace of keratin differentiation during cell turnover we injected bromodeoxyuridine (BrdU) into adult rats to monitor taste cell age. Keratin-19-positive intragemmal cells differentiated within 1 day. In contrast, keratin 18 was first detected in cells aged 3 days. Hence, both in taste cell development and replacement, keratin 18 was restricted to the older cells; it was the last taste cell keratin to become expressed during differentiation.

Animals↗
PubMed1995

[Olfactory neuroblastoma: a histopathological ultrastructural and immunohistochemical study of 11 cases].

Eleven cases of olfactory neuroblastoma (ONB) were studied histopathologically, ultrastructurally and immunohistochemically. Light microscopical examination showed the tumor cell nests separated by fibrous connective tissue (present in 10/11 ONB), Homer-Wright rosette and/or Flexner rosette (9/11 ONB) and acidophilic fibrillary background (8/11 ONB). Ultrastructurally, there were neurosecretory granules (2/2 ONB) and neurofibrils (1/2 ONB) in cytoplasm of tumor cells. A panel of antibodies were used to characterize the immunohistochemical staining profile of ONB. The following results were obtained for the 11 neoplasms that were immunostained: NSE 11/11 (+), S-100 3/11 (+), Vimentin 4/11 (+), Keratin 1/11 (+) and NF, EMA, CEA, LCA all negative respectively. The significance of the morphological and immunohistochemical features of ONB in diagnosis and differential diagnosis were discussed.

Adolescent↗
PubMed1995

[Rheumatic diseases in China].

To determine the prevalence of rheumatic diseases in Chinese of Han nationality in the north and the south of China, samples of 4,192 adults in Beijing (north) and 5,057 in Shantou (south) area were studied. The same questionnaire was administered to each subject surveyed. Physical examinations were done in all who gave positive answers. For those who gave positive response to certain set of questions, blood antinuclear antibody and rheumatoid factor tests and radiographs of hand and/or sacroiliac joint were done. The prevalence of definite rheumatoid arthritis (RA) was 0.34% in the north (95% confidence interval 0.20-0.51) and 0.32% (0.95% CI 0.16-0.47) in the south and ankylosing spondilitis was noted in 0.26% of both samples (95% confidence interval in the north 0.11-0.42 and in the south 0.14-0.40). Only 3 cases of systemic lupus erythematosus in the north and one in the south were identified. General rheumatic pain was reported more frequently in the north. Lumbar problems were recorded on examinations 5 times more commonly in the north than in the south (men 25.0% vs 5.3%, women 38.0% vs 6.5%) and knee problems 10 times (men 24.0% vs 1.8%, women 36.0% vs 3.4%) more commonly in the north; the difference was greatest in the age of 55-64. A further study in the south is planned to assess the contribution of inter-observer error and/or difference in cultural response to the north/south difference observed in the prevalence of general rheumatic symptoms and back pain. A search for environmental risk factors such as climate, diet, degeneration or overuse would then be indicated to explain these differences.

Adult↗
PubMed1995

[Osteoarthritis: clinical and epidemiological investigation].

A population study of 1,722 adults in Chenghai city, Guangdong province showed that the prevalence of osteoarthritis (OA) was 8.3% and there was no significant difference between male and female. The prevalence of OA increased after the age of 40 and reached a peak at 50-55 years. The prevalence of osteoporosis (OP) in OA patients of this population survey and in patients in our clinic was around 30%. OA accompanying OP was more frequently seen in female than male, especially in postmenopausal women. The results of CT screen of lumbar spine in 66 OA patients showed: 89.4% (59 cases) was associated with the protrusion of intervertebrale disc, occurring frequently at L4 and L5. MR imaging of 20 knee joints in 10 cases of OA patients with knee involvement showed: all of the patients were associated with one or all of the following conditions: chondropathies, degeneration or injury of semilunar plate, bursitis and synovitis. It is suggested that OA is a heterogeneous disorder and must be treated with different ways.

Adult↗