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1.
Diabeticperipheralneuropathy(DN)isoneofthemostcommondiabeticcomplica tions.Itspathogenesisisstillunclear,sonodefinitelyeffectivemedicinehasbeenfound.ClinicalsymptomsofDNcouldbesignificantlyrelievedbyJinmaitongcomposita(JMTC,复方筋脉通),atraditionalChinese…  相似文献   
2.
The role of special ‘Diabetic’ foods in the diabetic diet is considered and the following conclusions are drawn.
  • 1 Most diabetic foods provide slightly, but not substantially, less energy than comparable non-diabetic products.
  • 2 Many diabetic foods have a higher fat content than their non-diabetic equivalents. This is contrary to the requirements of the 1984 Food Labelling Regulations.
  • 3 Many diabetic products have a relatively high content of protein.
  • 4 In percentage terms, the greatest difference between diabetic and non-diabetic foods remains that of carbohydrate content, particularly carbohydrate other than fructose or sorbitol. On a per portion basis (for instance per teaspoon of jam) the difference is relatively small and likely to be of minimal practical significance.
  • 5 Diabetic foods cost between 1.5 and 4 times as much as their non-diabetic equivalents.
  • 6 Some ordinary reduced-sugar/low-calorie products are preferable to diabetic products in terms of fat and energy content and cost.
  • 7 The promotion and widespread availability of diabetic foods tend to delude patients into believing that these products are advantageous, or even necessary. Their existence also undermines current dietary teaching by implying that diabetics cannot eat normal foods.
  • 8 Diabetic foods offer no significant physiological or psychological benefits to diabetic patients and can even be counterproductive to good diabetic control. There is no longer a need for special diabetic foods in the modern dietary management of diabetes.
  相似文献   
3.
Protocatechuic acid (PCA) at 0.5%, 1% or 2% was supplied to d-galactose (DG) treated mice for 8 week. PCA intake at 2% increased its deposit in brain. DG treatment increased brain level of reactive oxygen species, protein carbonyl, carboxymethyllysine, pentosidine, sorbitol, fructose and methylglyoxal (P < 0.05). PCA intake, at 1% and 2%, lowered brain level of these parameters (P < 0.05). DG treatments enhanced activity and protein expression of aldose reductase (AR) and sorbitol dehydrogenase, as well as declined glyoxalase I (GLI) activity and protein expression (P < 0.05). PCA intake at 1% and 2% reduced activity and protein expression of AR (P < 0.05), and at 2% restored GLI activity and expression (P < 0.05). DG injection also elevated cyclooxygenase (COX)-2 activity and expression, and increased the release of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha and prostaglandin E2 in brain (P < 0.05). PCA intake decreased these cytokines (P < 0.05), and at 1% and 2% suppressed COX-2 activity and expression (P < 0.05). PCA intake at 1% and 2% also lowered DG-induced elevation in activity, mRNA expression and protein production of nuclear factor kappa B p65 (P < 0.05). These findings suggest that the supplement of protocatechuic acid might be helpful for the prevention or alleviation of aging.  相似文献   
4.
目的探讨糖尿病腰椎管狭窄患者黄韧带增生肥厚的发生机制。方法 24例糖尿病和20例非糖尿病的腰椎管狭窄患者列为研究对象,观测黄韧带标本结构,D-Sorbitol/Xylitol试剂盒检测山梨醇水平。体外实验中使用小鼠成纤维细胞(NIH3T3)细胞系,用Western blot及q PCR分别检测高糖培养条件及醛糖还原酶抑制剂(ARI):依帕司他(EP)作用对细胞炎性反应因子及TGF-β表达水平的影响。结果糖尿病组较非糖尿病组的山梨醇水平更高、黄韧带平均厚度更大、标本弹力纤维降解、胶原纤维增生更为显著、免疫组化CD68阳性染色率更高(P0.01);体外实验中,NIH3T3细胞系在高糖培养与正常糖浓度培养相比山梨醇、促炎性细胞因子和TGF-β表达水平更高,而山梨醇、促炎性细胞因子和TGF-β增高的表达水平可被醛糖还原酶抑制剂所抑制并且呈剂量依赖(P0.05)。结论糖尿病腰椎管狭窄患者黄韧带中山梨醇水平显著增高,进而促进炎性反应因子及纤维化相关因子TGF-β表达增加,使得黄韧带炎性增生。  相似文献   
5.
Summary Aldose reductase inhibitors (ARIs) attenuate diabetic complications in several tissues, including lens, retina, kidney, blood vessels, striated muscle and peripheral nerve. However, it is unclear whether their action in diabetes mellitus depends directly on inhibiting the conversion of glucose to sorbitol by aldose reductase or indirectly by reducing the sorbitol available for subsequent metabolism to fructose by sorbitol dehydrogenase. To identify the polyol pathway step most relevant to complications, particularly neuropathy, we compared the biochemical effects of a sorbitol dehydrogenase inhibitor, WAY-135 706, (250 mg · kg−1· day−1) and an ARI, WAY-121 509, (10 mg · kg−1· day−1) on a variety of tissues, and their effects on nerve perfusion and conduction velocity. After 6 weeks of untreated streptozotocin diabetes, rats were treated for 2 weeks. Sorbitol was elevated 2.1–32.6-fold by diabetes in lens, retina, kidney, aorta, diaphragm, erythrocytes and sciatic nerve; this was further increased (1.6–8.2-fold) by WAY-135 706 whereas WAY-121 509 caused a marked reduction. Fructose 1.6–8.0-fold elevated by diabetes in tissues other than diaphragm, was reduced by WAY-135 706 and WAY-121 509, except in the kidney. Motor and sensory nerve conduction velocities were decreased by 20.2 and 13.9 %, respectively with diabetes. These deficits were corrected by WAY-121 509, but WAY-135 706 was completely ineffective. A 48.6 % diabetes-induced deficit in sciatic nutritive endoneurial blood flow was corrected by WAY-121 509, but was unaltered by WAY-135 706. Thus, despite profound sorbitol dehydrogenase inhibition, WAY-135 706 had no beneficial effect on nerve function. The data demonstrate that aldose reductase activity, the first step in the polyol pathway, makes a markedly greater contribution to the aetiology of diabetic neurovascular and neurological dysfunction than does the second step involving sorbitol dehydrogenase. [Diabetologia (1997) 40: 271–281] Received: 13 August 1996 and in final revised form: 6 December 1996  相似文献   
6.
Normal subjects may incompletely absorb either lactose, fructose, or sorbitol and may therefore have abdominal symptoms. The frequency of coincidental malabsorption of these sugars is not known. This is clinically important, since we often ingest them during the same day and malabsorption may cause abdominal symptoms. To shed light on this issue we studied 32 normal subjects. Volunteers drank in random order the following solutions: 20 g lactulose, 50 g sucrose, 50 and 25 g lactose, 50 and 25 g fructose, 20 and 10 g sorbitol. Semiquantitative carbohydrate malabsorption was estimated with lactulose standards. Frequency of 50-g lactose (69%), 50-g fructose (81%), and 20-g sorbitol (84%) malabsorption was not significantly different (P = 0.3). The estimated median fraction of the ingested high dose malabsorbed was 42, 19, and 68% for lactose, fructose, and sorbitol, respectively. At low challenging doses, 63% of the volunteers absorbed two of three or all three sugars, and 88% were asymptomatic to two or all three sugars. In conclusion, the frequency of coincidental malabsorption of lactose, fructose, and sorbitol and intolerance to these sugars is not common, when normal adults ingest them at low doses.  相似文献   
7.
CJ‐12,918, a 5‐lipoxygenase (5‐LO) inhibitor, caused cataracts during a 1‐month safety assessment studies in rats whereas the structurally similar ZD‐2138 was without effect. For CJ‐12,918 analogs, blocking different sites of metabolic liability reduced (CJ‐13,454) and eliminated (CJ‐13,610) cataract formation in both rats and dogs. Using this chemical series as a test set, models and mechanisms of toxicity were first explored by testing the utility of ex vivo rat lens explant cultures as a safety screen. This model overpredicted the cataractogenic potential of ZD‐2138 due to appreciably high lens drug levels and was abandoned in favor of a mechanism‐based screen. Perturbations in lens sterol content, from a decline in lathosterol content, preceded cataract formation suggesting CJ‐12,918 inhibited lens cholesterol biosynthesis (LCB). A 2‐day bioassay in rats using ex vivo LCB assessments showed that the level of LCB inhibition was correlated with incidence of cataract formation in animal studies by these 5‐LO inhibitors. Thereafter, this 2‐day bioassay was applied to other pharmaceutical programs (neuronal nitric oxide synthase, sorbitol dehydrogenase inhibitor, squalene synthetase inhibitor and stearoyl‐CoA desaturase‐1 inhibitors/D4 antagonists) that demonstrated cataract formation in either rats or dogs. LCB inhibition >40% was associated with a high incidence of cataract formation in both rats and dogs that was species specific. Bioassay sensitivity/specificity were further explored with positive (RGH‐6201/ciglitazone/U18666A) and negative (tamoxifen/naphthalene/galactose) mechanistic controls. This body of work over two decades shows that LCB inhibition was a common mechanism of cataract formation by pharmaceutical agents and defined a level of inhibition >40% that was typically associated with causing cataracts in safety assessment studies typically ≥1 month.  相似文献   
8.
Modified gum acacia, produced from acacia gum by a process analogous to the production of modified food starch, was tested for mutagenicity in the microbial reverse mutation assay. The assay employed a wide range of dose levels, both with and without metabolic activation. Test results gave no indication that modified gum acacia possessed any mutagenic potential. The acute oral toxicity of modified gum acacia was determined in two studies employing Sprague-Dawley rats, and the LD50 values were found to be >2000 mg/kg. The primary dermal irritation potential of modified gum acacia was evaluated in rabbits by the Draize method. Test results indicated that modified gum acacia was slightly irritating by the Environmental Protection Agency (EPA) classification but not a primary irritant by Consumer Product Safety Commission (CPSC) guidelines. The subchronic toxicity of modified gum acacia was examined in Sprague-Dawley rats fed diets containing 0%, 1%, 2.5%, and 5% modified gum acacia for 13 weeks. No dose-related effects on survival, growth, hematology, blood chemistry, organ weights, or pathologic lesions were observed. Results of these studies indicate that modified gum acacia does not possess mutagenic potential and that animals are not adversely affected by acute or subchronic exposure to modified gum acacia.  相似文献   
9.
目的探讨肝内门-体分流(IPSS)在大鼠肝缺St/再灌注(I/R)损伤中的作用和机制。方法健康雄性SD大鼠12只,作右侧颈动脉、颈静脉插管,开腹后,经回结肠静脉作门静脉插管,分别用以输血、输液、给药、留样、检测等。随机分为2组(每组6只)。假手术组(对照组):术中只分离肝周围韧带,不作肝门阻断及再灌注。I/R组:进行45min的部分肝门阻断及60min的再灌注。待I/R组再灌注60min后,2组于相同时点经门静脉输注D-山梨醇(10mmol/L,0.2ml/min),同时取颈动脉、门静脉、肝静脉血各1ml待测山梨醇浓度。电磁血流量计测定门静脉血流量(PVF)、肝动脉血流量(HAF)。根据颈动脉、门静脉、肝静脉的山梨醇浓度及PVF、HAF,计算肝山梨醇摄取率、功能性肝血流量(FHBF)和肝内门-体分流量(IHSF)。结果与对照组相比,I/R组肝山梨醇摄取率和FHBF减少,IHSF增加(P〈0.01)。结论肝I/R过程中,IPSS开放、FHBF减少可能与再灌注损伤有关。  相似文献   
10.
There are increasing numbers of adults living in the community who require enteral tube feeding. While there is significant evidence of the importance of this treatment, there are side effects which can cause difficulties for patients, their carer tabers and health professionals. Gastrointestinal complications are the most common side effects with feed formula being cited as the main culprit, often without investigating other potential causes. Many patients requiring aggressive nutrition support also require concurrent drug therapy to manage underlying disease. Drugs are often given via tubes in liquid form. These elixirs often contain large quantities of sorbitol, which will increase the osmolar concentration. There is a lack of awareness from primary health-care professionals about the difficulties that can arise when giving medications to patients receiving enteral feeding which may affect patient care and the nutritional outcomes.  相似文献   
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