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191.
Data from the Manitoba Longitudinal Study on Aging (MLSA) were used to test the hypothesis that self-rated health (SRH) is a predictor of mortality independent of "objective health status" (OHS). Subjects were a random sample of non-institutionalized residents of Manitoba aged 65+ in 1971 (n = 3,128). A single item measure of SRH was obtained during a survey conducted in 1971; a baseline measure of OHS was derived from physician and self-reported conditions and health service utilization data. Occurrence and date of death during the years 1971-1977 were known. Analyses of the data revealed that, controlling for OHS, age, sex, life satisfaction, income and urban/rural residence, the risk of early mortality (1971-1973) and late mortality (1974-1977) for persons whose SRH was poor was 2.92 and 2.77 times that of those whose SRH was excellent. This increased risk of death associated with poor self-rated health was greater than that associated with poor OHS, poor life satisfaction, low income and being male. These findings provide empirical support for the long held, but inadequately substantiated, belief that the way a person views his health is importantly related to subsequent health outcomes. 相似文献
192.
H C Shapiro L M Edelstein R P Patel M R Okun M Blackburn M Snyder T Brennan G Wilgram 《The Journal of investigative dermatology》1979,72(4):191-193
Validity of the tritiated water assay technique for tyrosine hydroxylase activity as a qualitative method was demonstrated with mushroom tyrosinase. Using this method, isolated murine melanoma "tyrosinase" (L-dopa oxidase) showed no tyrosine hydroxylase activity. This finding supports previous studies in our laboratory which used a variety of histochemical and biochemical methods. The nonenzymatic production of tritiated water caused by tritium exchange with hydrogen peroxide complicates the use of the tritiated water assay technique with crude systems, since hydrogen peroxide is generated by a variety of oxidase reactions. For this reason, previous studies using the tritiated water assay technique with crude systems are ambiguous. 相似文献
193.
D Resnick I L Dwosh T G Goergen R F Shapiro R D'Ambrosia 《AJR. American journal of roentgenology》1976,126(6):1181-1188
Eleven patients with ankylosing spondylitis underwent reconstructive hip surgery (21 hips). In 10 of these hips multiple surgical procedures had been performed. The final procedure included total hip arthroplasties (16 hips), femoral cup arthroplasties (four hips) and an Austin-Moore prosthetic replacement (one hip). A clinical and radiographic evaluation in the postoperative period revealed a high incidence of decreased joint motion and heterotopic ossification. Clinically moderate to severe restriction of motion was noted in 12 hips, and in six of these "reankylosis" was present. Radiographically moderate to severe new bone formation was seen in 11 hips, and in nine of these "reankylosis" was suggested. An association of excessive ossification and multiple surgical procedures was evident. It would appear that when the prime indication for hip surgery in patients with ankylosing spondylitis is restricted motion, the operation may not be beneficial. 相似文献
194.
Levin A Duncan L Djurdjev O Shapiro RJ Frohlich J Belanger A Dumas R Ross S 《Clinical nephrology》2000,53(2):140-146
BACKGROUND: Renal insufficiency is characterized by lipoprotein abnormalities including elevated triglyceride levels. PATIENTS AND METHODS: The safety and efficacy of micronized fenofibrate as a treatment for dyslipidemia in patients with progressive renal insufficiency was evaluated in a randomized, placebo-controlled double-blind study comparing fenofibrate and dietary modification to dietary modification alone. Patients were evaluated following a 3-month pre-randomization period of dietary counseling. Twenty-eight patients with moderate renal insufficiency and triglyceride levels 2.3 mmol/l or LDL/HDL ratio 5 were randomized to placebo (n = 12) or fenofibrate (n = 16) therapy. Treatment and dietary counseling continued for 6 months. RESULTS: Ten of 16 patients (63%) treated with fenofibrate achieved a 30% reduction in triglyceride levels or LDL/HDL ratio reduction < 5 compared to 2 of 17% in the placebo group (p = 0.015). Triglyceride levels were significantly reduced in the fenofibrate group (-31%) versus placebo (+1.3%, p = 0.003). In compliant patients (n = 25) there was also a significantly greater increase in HDL cholesterol levels in the fenofibrate group (+19.9%) compared to placebo (-4.7%, p = 0.001). Changes in measured creatinine clearance were not significantly different between the groups and there were no serious adverse effects of treatment. CONCLUSION: Fenofibrate therapy combined with dietary modification effectively reduced triglyceride levels in renal insufficiency patients without serious adverse effects. 相似文献
195.
Lori E Shapiro Sandra R Knowles Elizabeth Weber Manuela G Neuman Neil H Shear 《Drug safety》2003,26(3):187-195
OBJECTIVE: To evaluate cross reactivity between sulfonamide antimicrobials and celecoxib in patients with histories of allergies to sulfonamide antimicrobials. METHODS: Immunocompetent patients with a history of sulfonamide antimicrobial allergy who were being considered for therapy with celecoxib were prospectively enrolled. Sulfamethoxazole and trimethoprim skin prick and intradermal testing and/or an in vitro lymphocyte toxicity assay were performed. If skin testing was negative, an oral challenge with sulfamethoxazole and trimethoprim was performed. Oral challenges with celecoxib were administered to all patients. RESULTS: Twenty-eight immunocompetent patients (26 female; mean age 60 years) were evaluated. History of sulfonamide antimicrobial allergy included urticaria (n = 7), cutaneous eruptions (n = 9), and other (n = 12). Four of the 28 patients who were skin prick tested were positive to sulfamethoxazole and two of the ten patients who underwent in vitro testing were positive to sulfamethoxazole. All 28 patients were administered celecoxib and tolerated the medication. Phone call follow up in 25 patients disclosed that 15 patients continued to take celecoxib, while five patients did not take celecoxib following the oral challenge, and five discontinued celecoxib due to adverse effects, lack of drug efficacy or physician preference. CONCLUSIONS: Confusion exists regarding the potential for cross reactivity between sulfonamide antimicrobials and other sulfonamide-containing compounds. The six sulfonamide-allergic patients tolerated celecoxib uneventfully. This pilot study supports the hypothesis that the potential for cross-reactivity between celecoxib and sulfonamide antimicrobials appears to be low. However, further investigations are required to confirm this. 相似文献
196.
197.
198.
The involvement of the proliferating cell nuclear antigen (PCNA) in the
process of DNA repair induced by alkylating agents or by oxidative damage
was investigated in human quiescent fibroblasts by immunofluorescence and
flow cytometry. Transition from soluble to the DNA-bound form of PCNA, was
taken as the parameter to determine its involvement in repair DNA
synthesis. Treatment with the alkylating agents methylmethane sulfonate and
N-methyl-N'-nitro-N-nitrosoguanidine resulted in the rapid and
dose-dependent increase in the nuclear binding of PCNA. Similar results
were obtained with compounds such as hydrogen peroxide or tert-butyl
hydroperoxide, which are known to induce oxidative DNA damage. Tert-butyl
hydroperoxide may also generate malondialdehyde through a reaction of lipid
peroxidation. This mutagenic and carcinogenic product has been previously
shown to form adducts with DNA. Therefore, the possibility that tert-butyl
hydroperoxide could induce DNA damage through this pathway was investigated
by incubating cells directly in the presence of malondialdehyde. Such
treatment resulted in an increase in immunofluorescence associated with
nuclear-bound PCNA. The ability of oxidative and alkylating agents to
induce the nuclear binding of PCNA was also assessed in proliferating
cells. In these conditions, treatment with hydrogen peroxide or
methylmethane sulfonate, resulted in an increase in nuclear-bound PCNA in
the G1 and in the G2 + M compartments, but not in S phase. At longer times
after treatment, PCNA immunostaining was reduced to basal levels, while an
increase in nuclear binding of p21(waf1/cip1) protein was found in
concomitance with cell-cycle arrest. These results indicate that agents
inducing DNA base alterations in vivo, promote the nuclear binding of PCNA.
These lines of evidence support the role of a PCNA-dependent reaction in
the base excision repair system.
相似文献
199.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献
200.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献