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1.
CONTEXT: Increasing evidences from experimental and human studies suggest that the activity of the growth hormone (GH/insulin-like growth factor-I) axis may contribute to the age-related cognitive decline and poor cognition in late life. OBJECTIVE: The aim of the present study was to evaluate the relationship of total serum free IGF-I and its binding protein-3 with cognitive performance in older persons aged 80 years or older. DESIGN: Data are from baseline evaluation of the ilSIRENTE study (n=353). Cognitive performance was evaluated using five items enclosed in the Minimum Data Set for Home Care assessment form: short-term memory, procedural memory, cognitive skills in daily decision making, verbal expression, comprehension. Free insulin-like growth factor-I (free IGF-I) and IGF-binding protein-3 (IGFBP-3) in blood were measured. Analysis of covariance (ANCOVA) was used to examine the relationship between cognitive impairment and the serum free IGF-I and IGFBP-3 concentrations, after adjustment for potential confounding variables. RESULTS: After adjustment for potential confounders, which included age, gender, education, cerebrovascular disease, ischemic heart disease, congestive heart failure, hypertension, diabetes, depression, Parkinson diseases, thyroid diseases, smoking status, alcohol abuse, body mass index, and number of medications, individuals with verbal expression problems (n=20) and individuals with comprehension problems (n=24) had a significantly lower serum levels of readily dissociable IGF-I than participants without cognitive impairments. The serum IGFBP-3 presented the same behavior of free IGF-I. CONCLUSION: The present study suggests that among old-old subjects living in the community lower levels of total serum free IGF-I and IGFBP-3 are associated with impairment of cognitive performance. This finding suggests that the GH/IGF-I axis may play an important role in the age-related decline of cognitive performance.  相似文献   
2.
The cytochrome P450 mono-oxygenase gene, CYP2D6 on chromosome 22q13 (ch22q13), has been inconsistently associated with Parkinson's disease. Associations with CYP2D6 have either been absent altogether or have involved more than one polymorphism, many of which have the same metabolic effect on gene expression. We examined the association between CYP2D6 polymorphisms and Parkinson's disease in a case-control study and included 10 polymorphic dinucleotide repeat markers linked to CYP2D6 to determine whether the association was present or due to linkage disequilibrium. There was no association between any polymorphism of CYP2D6 and Parkinson's disease, but two of 10 dinucleotide repeat markers linked to CYP2D6 were associated with the disease. These results provide evidence to suggest that there may be an unidentified locus for susceptibility to Parkinson's disease that is in linkage disequilibrium with dinucleotide repeat markers mapping near CYP2D6 on ch22q13.  相似文献   
3.
We examined the efficacy and safety of meso-2,3-dimercaptosuccinic acid (DMSA) in children with markedly elevated blood lead (BPb) concentrations. Among 19 children with BPb concentrations of 50 to 69 micrograms/dl (2.41 to 3.33 mumol/L) who received a 5-day inpatient oral course of DMSA (1050 mg/m2 per day), the mean BPb concentration decreased by 61%; in four who received calcium disodium ethylenediaminetetraacetic acid (CaNa2EDTA) (1000 mg/m2 per day intravenously), it decreased by 45% (p less than 0.0007). Urinary lead excretion was comparable in both groups. Treatment with DMSA was more effective than treatment with CaNa2EDTA in restoring metabolic activity to the heme pathway and was well tolerated even among nine patients who received concomitant iron supplementation and two who had homozygous deficiency of glucose-6-phosphate dehydrogenase. On discharge, these 19 children received either no chelation therapy or DMSA, 350 or 700 mg/m2 per day for 14 days on an outpatient basis. After 14 days the mean BPb values for the no-chelation, low-DMSA, and high-DMSA groups were 73%, 66%, and 50% of the pretreatment values, respectively. We conclude that a 5-day oral course of DMSA is effective in the treatment of children with severe lead poisoning. In addition, on an outpatient basis the administration of DMSA, 700 mg/m2 per day, is capable of delaying the typical rebound in BPb values and should ultimately reduce the need for repeated hospitalizations.  相似文献   
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For a prospective study of lead exposure and early development, we recruited pregnant women from a lead smelter town and from an unexposed town in Yugoslavia and followed their children through 7 years of age. In this paper we consider associations between lifetime lead exposure, estimated by the area under the blood lead (BPb) versus time curve (AUC7), and intelligence, with particular concern for identifying lead's behavioral signature. The Wechsler Intelligence Scales for Children-Version III (WISC-III) was administered to 309 7-year-old children, 261 of whom had complete data on intelligence, blood lead, and relevant sociodemographic covariates (i.e., Home Observation for the Measurement of the Environment (HOME), birth weight, gender, sibship size, and maternal age, ethnicity, intelligence, and education). These showed anticipated associations with 7-year intelligence, explaining 41-4% of the variance in Full Scale, Performance, and Verbal IQ. Before covariate adjustment, AUC7 was unrelated to intelligence; after adjustment, AUC7 explained a significant 2.8%-4.2% of the variance in IQ. After adjustment, a change in lifetime BPb from 10 to 30 micro/dl related to an estimated decrease of 4.3 Full Scale IQ points; estimated decreases for Verbal and Performance IQ were 3.4 and 4.5 points, respectively. AUC7 was significantly and negatively related to three WISC-III factor scores: Freedom from Distractibility, Perceptual Organization, and Verbal Comprehension; the association with Perceptual Organization was the strongest. Consistent with previous studies, the IQ/lead association is small relative to more powerful social factors. Findings offer support for lead's behavioral signature; perceptual-motor skills are significantly more sensitive to lead exposure than are the language-related aspects of intelligence.  相似文献   
6.
Although the use of methotrexate (MTX) is gaining acceptance in the treatment of several connective tissue diseases, there is little evidence of its therapeutic value in systemic lupus erythematosus (SLE). We examined the response to MTX in patients with steroid-resistant SLE in an open, unblinded study. Of 10 SLE patients treated with MTX (7.5 mg/weekly), 7 showed improvement. The other 3 stopped therapy because of lack of response or because of side effects. Improvements were noted within 3 months in responding patients. These promising observations suggest that controlled studies of MTX for the treatment of SLE are justified.  相似文献   
7.
Both prognosis and treatment of lymphomas depend strictly on both clinical staging and histologic classification. The role of US was investigated in the evaluation of patients affected with abdominal lymphoma. To this purpose, 52 patients affected with abdominal lymphoma underwent US and CT studies during staging, treatment, or follow-up. A comparison of the results of the two methods shows that the systematic use of US allows 5% of lymph nodes missed at CT to be demonstrated, together with hepatic and splenic involvement also undetected by CT. It is true, however, that the limited number of cases does not allow this result to be correlated with the histopathologic type of lymphopathy. US has also been the examination of choice to evaluate response to chemotherapy and to study suspected relapses. In the authors' opinion, US should become a complementary technique to CT in the staging of abdominal lymphomas.  相似文献   
8.
Previous studies have suggested that the loss of DNA sequences on the short arm of chromosome 3 (3p) is associated with small-cell lung carcinoma. We therefore looked for loss of 3p alleles in tumor tissue from 42 patients with either small-cell or non-small-cell lung carcinoma. All 13 patients with small-cell lung carcinoma who were heterozygous for one or more alleles at 3p in normal tissue had the loss of at least one codominant allele in the tumor tissue. Cell lines of small-cell lung carcinoma from an additional eight patients were homozygous for 3p alleles; this result was significantly different from the predicted frequency of homozygosity. The tumor tissue studied included cell lines of small-cell lung carcinoma obtained from biopsy specimens, an autopsy sample, and an excised lymph node containing tumor cells. Loss of alleles at 3p was observed in tumor samples obtained before and after chemotherapy. Four of 15 evaluable patients with non-small-cell carcinoma of the lung had loss of 3p alleles. We conclude that loss of alleles at 3p is a change found consistently in small-cell lung carcinoma and occasionally in non-small-cell lung carcinoma.  相似文献   
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10.
The biodegradability of solution-cast films of poly(D (–)-3-hydroxybutyrate) (PHB) blended with the melt-compatible component atactic poly(epichlorohydrin) (aPECH) was investigated. A bacterium which produced extracellular enzymes that degraded PHB even when blended with aPECH was isolated, and tentatively designated as Aureobacterium saperdae. The growth rate of A. saperdae decreased with increasing aPECH content in the blend, up to films containing 60 wt.-% aPECH, at which composition growth was completely inhibited. The decrease in the bacterial growth rate could be due to the dilution of PHB molecules on the blend film surface caused by the presence of aPECH molecules. At the stationary phase of bacterial growth the percentage of weight loss of blend films decreased with increasing aPECH fraction, which was probably due to the lower accessibility of PHB when blended with aPECH. During the bacterial growth only PHB was metabolized, whereas neither degradation nor abiotic release of aPECH was detected for blend films.  相似文献   
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