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D M Reed D J Foley L R White H Heimovitz C M Burchfiel K Masaki 《American journal of public health》1998,88(10):1463-1468
OBJECTIVE: The purpose of this study was to identify risk factors that consistently predict staying healthy in contrast to developing clinical illness and/or physical and mental impairments. METHODS: More than 8000 men of Japanese ancestry were followed for 28 years with repeat examinations and surveillance for deaths and incident clinical illness. Physical and cognitive functions were measured in 1993. Measures of healthy aging included surviving and remaining free of major chronic illnesses and physical and cognitive impairments. RESULTS: Of 6505 healthy men at baseline, 2524 (39%) died prior to the final exam. Of the 3263 available survivors, 41% remained free of major clinical illnesses, 40% remained free of both physical and cognitive impairment, and 19% remained free of both illness and impairment. The most consistent predictors of healthy aging were low blood pressure, low serum glucose, not smoking cigarettes, and not being obese. CONCLUSIONS: Beyond the biological effects of aging, much of the illness and disability in the elderly is related to risk factors present at midlife. 相似文献
36.
Bronchoalveolar lavage cell counts as a predictor of short term outcome in pulmonary sarcoidosis. 总被引:1,自引:1,他引:0
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Sixty seven patients with biopsy proven pulmonary sarcoidosis were prospectively studied to determine whether single point bronchoalveolar lavage cell counts were a useful indicator of functional outcome and whether repeated lavage helped in management. The mean follow up period was 25 (range 13-37) months. No patient was having corticosteroid treatment at the time of initial bronchoalveolar lavage. "High intensity alveolitis" (lymphocyte count greater than or equal to 28%) was present at the initial lavage in 42 patients. These patients showed a significant improvement in their pulmonary function and chest radiographs over the follow up period whereas patients with "low intensity alveolitis" did not. Of the 42 patients with high intensity alveolitis, 31 had chronic sarcoidosis (duration over two years, mean 80 months). These patients showed a significant improvement in FVC but not in TLCO. Corticosteroids resulted in greater functional and radiological improvement in the patients with high intensity alveolitis than in those with low intensity alveolitis. Repeat bronchoalveolar lavage in 34 patients, mean 8.4 months after the original lavage, showed a weak inverse relation between a reduced lymphocyte count and change in forced vital capacity and isotope uptake on a gallium scan. These correlations were too weak to make repeated cell counts useful in management. Our results suggest that high intensity alveolitis may be a favourable prognostic factor for lung function in pulmonary sarcoidosis, even in patients with chronic disease, but that repeat lavage adds little to the management of the individual patient. 相似文献
37.
Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
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2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) affects the thyroid morphologically and/or functionally in adult animals. Recently, the National Toxicology Program conducted a 2-year gavage study of TCDD in female Harlan Sprague-Dawley rats. The only treatment-related alterations found in thyroid follicles were decreased luminal size and increased height of the follicular epithelial cells, without prominent protrusion into the lumen. The present study elucidated the nature of these follicular lesions. Thyroid glands of 10 rats each from the control, high (100 ng/kg/day)-dose, and stop-study (100 ng/kg/day, 30 weeks; vehicle to study termination) groups in the 2-year study were evaluated microscopically. Twenty randomly selected follicles were measured morphometrically in each animal. TCDD treatment significantly decreased the mean ratio of luminal/epithelial areas and increased the mean sectional epithelial height of the high-dose group compared to controls. Thyroid sections were immunostained with antibody against minichromosome maintenance (MCM) proteins, a novel cell-cycle biomarker. The MCM labeling index of the high-dose group was significantly higher than that of the control; however, the TUNEL labeling index was also higher in the high-dose group than the control. All data from the stop group were comparable to those from controls. These results indicate that the follicular cell response was hypertrophic and reversible. This information should contribute to diagnosis of nonneoplastic thyroid follicular lesions in rats. 相似文献
39.
Del-Favero J; Krols L; Michalik A; Theuns J; Lofgren A; Goossens D; Wehnert A; Van den Bossche D; Van Zand K; Backhovens H; van Regenmorter N; Martin JJ; Van Broeckhoven C 《Human molecular genetics》1998,7(2):177-186
Autosomal dominant cerebellar ataxia with retinal degeneration (ADCAII) was
previously mapped by linkage analysis studies to chromosome 3p12- p21.1
(SCA7). Positional cloning efforts have recently identified a novel gene,
SCA7 , containing a translated CAG repeat, expanded in SCA7 patients. We
cloned the SCA7 gene from a yeast artificial chromosome (YAC) clone contig
spanning the SCA7 candidate region. Using a combination of genomic
sequencing and cosmid-based exon trapping, two expressed sequence tags were
identified. Sequencing of the corresponding cDNA clones and RT-PCR analysis
identified the full- length SCA7 cDNA. Together, our sequence data defined
the intron/exon boundaries of the first two coding exons of the SCA7 gene,
with the first exon containing the expanded CAG repeat. Further, sequence
comparison with the published SCA7 cDNA identified one additional putative
exon in the 5'-UTR region of the SCA7 gene. The SCA7 gene was mapped on the
YAC contig in the 2.5 cM interval between D3S1600 and D3S1287. In one
extended Belgian SCA7 pedigree the expanded alleles ranged from 38 to at
least 55 repeats with allele lengths being inversely correlated with onset
age of ADCAII symptoms. The SCA7 repeats increased in length in successive
generations. Normal alleles had from four to 18 repeats, with 10 repeats
being the most common allele.
相似文献
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