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41.
Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO2. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes. 相似文献
42.
43.
F. Sartucci G. Orlandi U. Bonuccelli D. Borghetti L. Murri C. Orsini L. Domenici V. Porciatti 《Neurological sciences》2006,26(6):395-401
Abstract Idiopathic Parkinson’s disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms
(PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are
not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green
(R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients
(mean age: 62±7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1±8.3
years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G,
B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not
significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and
luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for
B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early
IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing
MSA from IPD. 相似文献
44.
Restless legs syndrome (RLS) is one of the commonest movement disorders affecting sleep and also daytime functioning. The prevalence may be 8%–10% of the white Caucasian population. The diagnosis is simple and is based on a well-validated clinical questionnaire, yet misdiagnosis is common and the condition remains underdiagnosed and consequently inappropriately treated, often causing great distress to the sufferers. In spite of robust evidence for effective treatment of RLS, patients may often be told to “put up with the symptoms” and suffer the consequence of years of poor sleep which may lead to major lifestyle changes. This review addresses the diagnostic issues, the differential diagnosis, and the evidence base for treatment of the common condition. 相似文献
45.
Kiyoshi Hashizume Kazuo Ichikawa Satoru Suzuki Teiji Takeda Keishi Yamauchi Mutsuhiro Kobayashi Xiao-Yun MA 《Journal of bone and mineral metabolism》1992,10(2):39-49
Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction
on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets
would show any modification of parathyroid hormone (PTH) and calcitonin (CTN).
The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into
two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were
measured by competitive protein binding assays before and after each program.
The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that
(256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral
calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in
the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine
were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower
in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma
1,25-(OH)2-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When
the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase
in the 1,25-(OH)2-vitamin D levels, whereas their CTN levels were unchanged.
These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as
for a low serum level of CTN in patients with NIDDM. 相似文献
46.
Gsta Holmgren Sven Bergström Ulf Drugge Erik Lundgren Carin Nording-Sikström Ola Sandgren Lars Steen 《Clinical genetics》1992,41(1):39-41
Familial amyloidotic polyneuropathy (FAP) with a mutation in position 30 of transthyretin (TTR) (previously called prealbumin) is an autosomal dominant inherited disorder characterized by varying degrees of peripheral neuropathy, nephropathy, gastrointestinal problems, and vitreous amyloid. We have earlier diagnosed homozygosity for the TTR-Met30-gene using Southern analysis in four Swedish individuals. We have found it possible to detect homozygosity for the Met-30 mutation by amplifying discrete regions of the TTR-gene using polymerase chain reaction (PCR), and the amplification products restricted with NsiI analysed by gel electrophoresis. Clinical data on seven homozygous individuals, including three new cases, are presented. 相似文献
47.
变形链球菌F-ATP酶亚基基因uncA遗传多态性的研究 总被引:3,自引:0,他引:3
目的研究变形链球菌临床分离株耐酸因子F—ATP酶亚基α的结构基因uncA的遗传多态性,并探讨基因多态性与细菌耐酸力及龋病发生的关系。方法分别从高龋、无龋个体中分离变形链球菌34和30株,其中包括18株高耐酸株、20株低耐酸株。从细菌组DNA扩增uncA,行限制性内切酶长度多态性分析(RFLP)及核酸测序比较。结果不同限制性内切酶RFLP产生不同的基因型,测序证实了导致多态出现的基因变异;内切酶Hph Ⅰ产生的A、B基因型在不同患龋个体分离菌株的分布不同(P〈0.05),A型uncA在高龋分离株的检出率高于无龋分离株;内切酶MboⅡ产生的C、D基因型在不同耐酸力菌株中的分布不同(P〈0.05),C型uncA在高耐酸力菌株的检出率高于低耐酸力菌株。结论变形链球菌F—ATP酶的α亚基基因uncA具有明显遗传多态性,酸性环境下生存力强的菌株可能出现基因的适应性变异,不同基因型uncA分布与菌株的耐酸力及致龋力相关。 相似文献
48.
Tetrabenazine (TBZ), a presynaptic dopamine depletor and postsynaptic dopamine receptor blocker, is widely used for the treatment of hyperkinetic movement disorders in adults. However, reports of its use in children are limited. We review the efficacy and tolerability of TBZ therapy in 31 children with hyperkinetic movement disorders refractory to other medications. TBZ was effective in reducing the severity of movement disorders resistant to treatment with other medicines. When compared to adult patients, pediatric patients required higher doses. Side effects were similar to the adult population; however, children had a lower incidence of drug-induced Parkinsonism. 相似文献
49.
Zheng-Hua ZHU Bai-Ren WANG Qing-Rong TAN Xiao-Li DUAN Fang KUANG Zhen XU Gong JU Institute of Neurosciences Department of Psychiatrics the Fourth Military Medical University X i’an China 《中国神经科学杂志》2006,(3)
1 Introduction Exposure to hostile stressors causes a series of coor- dinated responses in the body, such as alterations of neu- roendocrine secretion, immune reaction and behavioral manifestation to maintain homeostasis stability and sur-vival of the organisms. Stressors are divided into two main categories: physical, or systemic, and psychological, or emotional / processive. Each stressor might activate a spe- cific central pathway to induce a special neuroendocrine response, even cause stre… 相似文献
50.