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1.
Summary The plasticizer DEHP but not DEHS exerted a weak promoting effect in a 12-week rat liver foci bioassay, using weanling female Sprague-Dawley rats. The effect was similar after doses of 200 and 500 mg/kg body weight, given 3 times weekly by gavage for 11 consecutive weeks after initiation with a single oral dose of 8 mg DEN/kg body weight. Lower doses were ineffective. The incidence of foci with deficiency in ATPase was enhanced about twice compared to rats treated with DEN only. The incidence of foci with expression of GGTase was not affected by DEHP treatment. The results match the findings with lifetime exposure studies, when liver tumors were found in rats and mice. The actual risk for man from environmental DEHP contamination seems to be low; the intake from highly contaminated food is calculated to be about 400-fold lower than the lowest effective dose in this study.Abbreviations DEHP di(2-ethylhexyl)phthalate - DEHS di(2-ethylhexyl)sebacate - ATPase adenosine-5-triphosphatase (EC 3.6.1.3) - GGTase gamma-glutamyltranspeptidase (EC 2.3.2.2) - DEN diethylnitrosamine Supported by grants from Umweltbundesamt Berlin (UBA 10604017)  相似文献   

2.
Exposures to di-(2-ethylhexyl) phthalate (DEHP) have been shown to be associated with decreased adult testosterone (T) levels and increased Leydig cell numbers. As yet, little is known about DEHP effects in utero on fetal Leydig cells (FLC). The present study investigated effects of DEHP on FLC function. Pregnant Long-Evans female rats received vehicle (corn oil) or DEHP at 10, 100, or 750 mg/kg by oral gavage from gestational day (GD)2-20. At GD21, T production, FLC numbers and distribution, and testicular gene expression were examined. The percentage of FLC clusters containing 6-30 cells increased in all treatment groups, with 29 +/- 2% in control vs. 37 +/- 3, 35 +/- 3, and 56 +/- 4% in rats receiving 10, 100, and 750 mg/kg DEHP, respectively. In contrast, FLC numbers were 33% and 39% lower than control after exposures to 100 and 750 mg/kg DEHP, respectively. At these doses, mRNA levels of leukemia inhibitory factor (LIF) increased. LIF was found to induce cell aggregation in FLCs in vitro, consistent with the hypothesis that DEHP induced FLC aggregation. Testicular T levels were doubled by the 10 mg/kg dose and halved at 750 mg/kg. The mRNA levels of IGF-1 and c-Kit ligand (KITL) were induced by 10 mg/kg DEHP. These results, taken together, indicate that fetal exposures to DEHP have effects on FLC number, distribution, and most importantly, steroidogenic capacity and suggest that abnormal expressions of IGF1, KITL, and LIF genes may contribute to the reproductive toxicity of phthalates.  相似文献   

3.
The modulating effects of female sex hormones, ethinylestradiol and levonorgestrel, on the development of renal proliferative lesions after initiation withN-nitrosobis(2-oxopropyl)amine (BOP) were investigated. Three groups of female Syrian golden hamsters, each comprising 30 animals, were given four weekly s.c. injections of BOP (10 mg/kg body weight) and then fed diet containing 1 ppm ethinylestradiol (group 1: BOP/EE), diet containing 10 ppm levonorgestrel (group 2) or basal diet (group 3) for the next 27 weeks. As hormone controls, two groups of 20 female hamsters each received diet containing 1 ppm ethynylestradiol (group 4) and 10 ppm levonorgestrel (group 5) from week 3 for 27 weeks without the prior initiation treatment. The severity of diffuse anisokarya, characterized by varied nuclear size and the incidence of dysplasias of the proximal tubular epithelia induced by BOP, were significantly increased in the BOP/EE group, indicating the promoting effects of the hormone. In the renal dysplastic lesions (smallcluster, cystic, clear-cell and acidophilic cell types), adenomas and nephroblastomas, increases in the numbers of argyrophilic proteins associated with nucleolar organizer regions (NOR) in the nucleus, suggesting a high proliferative activity, were seen in dysplasia of acidophilic cell types and adenomas. In addition, the number of bizarre NOR per nucleus was significantly higher in adenomas than in dysplasias and highest in nephroblastomas. This morphological change in NOR should therefore be a useful parameter for the diagnosis of malignancy of renal tumors.Abbreviations BOP N-nitrosobis(2-oxopropyl)amine - EE ethinylestradiol - LNG levonorgestrel - NOR nucleolar organizer regions  相似文献   

4.
Summary Glucokinase is among the few genes which may play a key role in both insulin secretion and insulin action. Glucokinase is present in pancreatic beta cells where it may have a key role in the glucose sensing mechanism, and it is present in hepatocytes, where it may participate in glucose flux. Glucokinase defects have recently been implicated in maturity-onset diabetes of the young. To examine the hypothesis that glucokinase plays a key role in the predisposition to common familial Type 2 (non-insulin-dependent) diabetes mellitus, we typed 399 members of 18 Utah pedigrees with multiple Type 2 diabetic individuals for two markers in the 5 and 3 flanking regions of the glucokinase gene. Linkage analysis was performed under both dominant and recessive models. We also repeated these analyses with individuals with impaired glucose tolerance who were considered affected if their stimulated (2-h) glucose exceeded age-specific normal levels for 95 % of the population. Under several dominant models, linkage was significantly excluded, and under recessive models log of the odds (LOD) score was less than –1. We were also unable to demonstrate statistical support for the hypothesis that a small subgroup of pedigrees had glucokinase defects, but the most suggestive pedigree (individual pedigree LOD 1.8–1.9) ranked among the youngest and leanest in our cohort. We can exclude a major role for glucokinase in familial Type 2 diabetes, but our data cannot exclude a role for this locus in a minority of pedigrees. Further testing of the hypothesis that glucokinase defects contribute to diabetes in a small proportion of Type 2 diabetic pedigrees must await thorough sequence analysis of the glucokinase gene, including regulatory regions, particularly from pedigrees with positive LOD scores.  相似文献   

5.
目的研究甲氰咪呱对非酒精性脂肪性肝炎(NASH)大鼠肝微粒体细胞色素P450的影响。方法通过高脂饮食制作非酒精性指肪性肝炎(NASH)动物模型,给予甲氰咪呱灌胃治疗,观察肝组织病理形态变化,进行炎症活动计分,同时测定细胞色素P450(CYP450)和细胞色素2E1(CYP2EI)含量及ALT、AST,并与对照组比较。结果与正常组比较,模型组大鼠ALT、AST及CYP450和CYP2EI含量明显升高;与模型组比较,甲氰咪呱治疗组CYP450和CYP2EI含量均明显下降,(P〈0.05),ALT、AST及炎症活动计分明显低于模型组(P〈0.05)。结论甲氰咪呱能显著改善NASH大鼠肝脏功能及形态损伤,可能通过抑制肝细胞微粒体CYP450和同功酶CYP2EI的表达发挥作用。  相似文献   

6.
Summary Nodules developing under the skin of rats after repeated injections of N-Nitroso-bis-(2-hydroxy-propyl)amine (BHP) are shown to contain no unchanged BHP  相似文献   

7.
Summary We describe the in vivo localization of radiolabeled mAb J28, a murine monoclonal antibody characterizing the oncodevelopmental human fetoacinar pancreatic (FAP) protein, at different stages of chemical induction of pancreatic tumors in the Syrian golden hamster. Before doing localization studies in this model, we looked at the cross-reactivity of mAb J28. Semiquantitative dot-blot analysis demonstrated that the antigen recognized in hamster pancreas has an oncodevelopmental expression pattern, while a molecular mass identical to that of human FAP was deduced from sodium dodecyl sulfate/polyacrylamide gel electrophoresis/nitrocellulose immunoblot.125I-labeled mAb J28 was administrated through micro-osmotic pumps to hamsters treated withN-nitrosobis(2-hydroxypropyl)amine (BHP). This was done at three intervals that roughly correspond to the latent period, pretumoral stages, and terminal cancerogenesis in two independent groups of hamsters. Both studies allowed similar results: (a) mAb J28 accumulated almost specifically in the pancreas; (b) maximal accumulation was associated with pleomorphic alterations of the acinar cell tissue at pretumoral stages; (c) no accumulation was found in the case of adenocarcinoma of the pancreas. It is concluded that FAP behaves as a marker of preneoplastic lesions, and therefore that radioimmunoimaging with mAb J 28 might help with early diagnosis of pancreatic cancer.Abbreviations BHP N-nitrosobis(2-hydroxypropyl)amine - FAP protein fetoacinar pancreatic protein - PBS phosphate-buffered saline - SDS-PAGE sodium dodecyl sulfate/polyacrylamide gel electrophoresis - BOP N-nitrosobis(2-oxopropyl)amine  相似文献   

8.
目的 探讨数据包络分析(DEA)在2型糖尿病不同医疗方案经济学评价中的应用。方法 采用临床随机试验的方法,将入组的2型糖尿病患者分为不同的医疗方案组进行治疗,然后进行随访观察。对各随访期内的成本和医疗后果进行测量,然后使用DEA对不同医疗方案的投入和产出进行综合评价。结果 常规治疗组和强化治疗组1年例均总费用分别为1403.78元和1460.83元,差异无统计学意义(P〉0.05);强化治疗组的各临床疗效优于常规治疗组,且获得了比常规治疗组更多的质量调整生命年(QALYs)(P〈0.05)。与常规治疗方案相比,强化治疗方案为DEA有效,其投入和产出达到了最优。结论 DEA可作为2型糖尿病不同医疗方案经济学评价的有效手段,强化治疗方案比常规治疗方案具有更好的经济学效果。  相似文献   

9.
Two kinds of 3-hydroxypyridine-2(1H)-thiones were synthesized. The visible (VIS) spectroscopic analysis indicated that 3-hydroxy-1-methylpyridine-2(1H)-thione (4a) and 3-hydroxy-1-(2-hydroxyethyl)pyridine-2(1H)-thione (4b) formed stable 3:1 Fe(III) complexes. The stability constant of the 4b-Fe(III) complex was estimated from the competitive reaction with EDTA and was found to be 36.7 in logβ3. Treatment of compound 4b with Ga(acac)3 in D2O:CD3OD (9:1) solution afforded 3:1 Ga(III) complex, which was assigned by means of 1H nuclear magnetic resonance (1H NMR) spectroscopy. Treatment of compound 4b with Pb(NO3)2 gave 4b-Pb(II) complex. The Pb(II) selectivity over biologically relevant Mg(II) and Ca(II) was remarkably improved by adopting N-hydroxyethyl functionality instead of N-methyl group.  相似文献   

10.
SARS-CoV-2 uses the ACE2 receptor and the cellular protease TMPRSS2 for entry into target cells. The present study aimed to establish if the TMPRSS2 polymorphisms are associated with COVID-19 disease. The study included 609 patients with COVID-19 confirmed by RT-PCR test and 291 individuals negative for the SARS-CoV-2 infection confirmed by RT-PCR test and without antibodies anti-SARS-CoV-2. Four TMPRSS2 polymorphisms (rs12329760, rs2298659, rs456298, and rs462574) were determined using the 5′exonuclease TaqMan assays. Under different inheritance models, the rs2298659 (pcodominant2 = 0.018, precessive = 0.006, padditive = 0.019), rs456298 (pcodominant1 = 0.014, pcodominant2 = 0.004; pdominant = 0.009, precessive = 0.004, padditive = 0.0009), and rs462574 (pcodominant1 = 0.017, pcodominant2 = 0.004, pdominant = 0.041, precessive = 0.002, padditive = 0.003) polymorphisms were associated with high risk of developing COVID-19. Two risks (ATGC and GAAC) and two protectives (GAGC and GAGT) haplotypes were detected. High levels of lactic acid dehydrogenase (LDH) were observed in patients with the rs462574AA and rs456298TT genotypes (p = 0.005 and p = 0.020, respectively), whereas, high heart rate was present in patients with the rs462574AA genotype (p = 0.028). Our data suggest that the rs2298659, rs456298, and rs462574 polymorphisms independently and as haplotypes are associated with the risk of COVID-19. The rs456298 and rs462574 genotypes are related to high levels of LDH and heart rate.  相似文献   

11.
The inv(16)(p13q22) and t(16;16)(p13;q22) in acute myeloid leukaemia are associated with a relatively good prognosis but are difficult to detect using classic cytogenetics. We have designed a two-colour fluorescence in situ hybridization approach that uses two DNA probes that map close to and on either side of the inv(16) p-arm breakpoint region. This new strategy clearly detected the inv(16)(p13q22)/t(16;16)(p13;q22) on both metaphase chromosomes and in interphase nuclei, even when they are of poor quality. This procedure also detected the inv(16) in cases with an additional deletion of sequences proximal to the 16p-arm breakpoint which is present in 20% of all cases.  相似文献   

12.
Summary The possibility of linkage between the human insulin receptor gene locus and diabetes was examined in three Type 2 (non-insulin-dependent) diabetic families and one family with maturity onset diabetes of the young. Insulin receptor gene haplotypes were established using BglII, Rsal and Sstl restriction enzyme digests of genomic DNA from all available family members. The digested DNA was subjected to agarose gel electrophoresis, Southern blotted, and hybridised to 32P-labelled human insulin receptor gene cDNA. In the pedigree with maturity onset diabetes of the young, formal linkage analysis allowed exclusion of close linkage between the insulin receptor locus and diabetes (logarithm of the odds for linkage versus non-linkage was –5.35 at recombination fraction of 0.01). This confirms the absence of linkage between insulin receptor and diabetes which has been reported in two similar pedigrees. In the three Type 2 diabetic families there were a minimum of 4 recombinants between the insulin receptor locus and diabetes, which makes a direct role for insulin receptor defects unlikely. The importance of using realistic estimates of penetrance when performing linkage analysis in a disease with a late age of onset is emphasised. In contrast to the one previous linkage analysis study of the insulin receptor gene, no specific association of diabetes with the rare Sstl Sl(-) allele was observed in either the maturity onset diabetes of the young or the Type 2 diabetic families.  相似文献   

13.
Within the core region of hypersensitive site 2 of the beta-globin locus control region is the (AT)xNz(AT)y motif, which comprises two short tandem repeats of dinucleotide (AT) interrupted by a short variable DNA sequence (Nz). The motif is usually investigated using direct sequence analysis of specifically amplified DNA, but without family studies, phase alignment of the two tandem repeats, occasionally confounded by a variable N sequence in between, can be erroneous. We combined the technique of automated genotyping with direct sequence analysis to demonstrate that it is possible to overcome this problem; the approach should be applicable for the investigation of other sequence repeats of this nature.  相似文献   

14.
15.
Thromboxane synthase forms thromboxane (TX) A2 and 12(S)-hydroxyheptadeca-5(Z)-8(E)-10(E)-trienoic acid (HHT) at equimolar amounts. Twelve-oxoheptadeca-5(Z)-8(E)-10(E)-trienoic acid (Oxo-HT) is the primary metabolite of HHT and has been described to be an inhibitor of platelet aggregation. Functional studies, Schild analysis and competitive binding studies were performed to clarify its mode of action. Oxo-HT was prepared biosynthetically as well as chemosynthetically, purified and characterized by gas chromatography and mass spectrometry. Platelet activation was assessed by determination of shape change, aggregation, fibrinogen binding and P-selectin expression using optical aggregometry and flow cytometry. Oxo-HT 0.1 n M to 50 μM did not induce platelet activation. Furthermore, it had no effect on platelet activation induced by thrombin, ADP or PAF. In contrast, Oxo-HT inhibited platelet aggregation, fibrinogen binding and P-selectin expression induced by U46619 in a competitive manner. Schild analysis for U46619-induced fibrinogen binding and P-selectin expression revealed pA2 values of 6.1 and 6.6, respectively, which correspond to Kd values of approximately 0.8 μM and 0.3 μM , respectively. Oxo-HT also inhibited U46619 induced shape change (IC50 ? 10 μM ). However, Oxo-HT over a concentration range of 0.1–1 μM enhanced the partial shape change induced by low concentrations of U46619. Thus Oxo-HT seems to possess a minimal agonistic potential, which alone is not sufficient to trigger a platelet activation but can enhance low levels of platelet activation. Oxo-HT blocked the binding of [3H]SQ 29548 in a concentration-dependent manner, whereas HHT did not displace [3H]SQ 29548. The Kd of Oxo-HT determined from competition binding studies was 7.7 μM , about 10–25-fold higher than the apparent Kd determined by Schild analysis. This discrepancy might be due to a desensitization of the TXA2 receptor triggered by the minimal intrinsic activity of Oxo-HT. We conclude that Oxo-HT is a naturally occurring specific TXA2 receptor antagonist with minimal intrinsic activity. Oxo-HT may contribute to the regulation of TXA2-induced platelet activation in vivo.  相似文献   

16.
Summary Is the course leading to diabetic end-stage renal disease similar for Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetes mellitus? We identified all diabetic end-stage renal disease patients starting renal replacement therapy from 1989 to 1991 in two urban counties in Texas. Three ethnic/racial groups were enrolled: Mexican Americans, non-Hispanic Whites, African Americans. Patients were interviewed and their medical records, both inpatient and out-patient, were abstracted for relevant diagnostic and therapeutic information. We attempted to obtain records as far back as the onset of diabetes or hypertension and from all physicians who had cared for the patient. An historical algorithm was used to determine diabetic type. Of the patients enrolled, 91 were Type 1 and 438 were Type 2 diabetic patients. Type 1 diabetic patients had higher mean glucose levels in the first 10 years of diabetes (16.3 vs 11.4 mmol/l) but lower systolic blood pressures (148 vs 157 mmHg). The duration of diabetes prior to end-stage renal disease was longer for Type 1 than Type 2 patients (22 vs 17 years). Type 1 diabetic patients were more likely to have other microvascular complications (retinopathy, neuropathy, gastroparesis), less likely to have coronary disease (myocardial infarction and congestive heart failure), and had similar rates of stroke and vascular surgery procedures (carotid endarterectomy, coronary artery bypass surgery, aortofemoral bypass). Type 1 and Type 2 diabetic patients were just as likely to have a first degree relative with hypertension (60.5 vs 65.5%). The late manifestations of end-stage renal disease were similar between the two groups (kidney size, proteinuria, slope of the inverse of creatinine, laboratory data prior to end-stage renal disease, reasons for starting dialysis). The course to end-stage renal disease may be different for Type 1 and Type 2 diabetes, with hyperglycaemia playing a more dominant role in Type 1 and hypertension playing a more dominant role for Type 2. The Type 1/Type 2 differences in patterns of other diabetic complications add weight to this hypothesis. However, the late course of the renal disease and the end result on the kidney is very similar.  相似文献   

17.
BACKGROUND AND AIM: Ulcerative colitis (UC) is a multifactorial disease resulting from a complex interaction of genetic and environmental factors. Identifying genetic variants that alter the innate immune response is highly relevant to understanding the pathogenesis of UC. The aim of this study was to investigate the association between CD14 and Toll-like receptor-2 (TLR2) genetic polymorphisms and chronic UC in Japanese patients. METHODS: The study population consisted of 102 chronic UC patients and 146 healthy control subjects. Polymorphisms in the promoter at C-260T of CD14 gene were investigated by PCR restriction fragment length polymorphism, and -196 to -174 del of TLR2 was investigated by allele-specific PCR. RESULTS: The frequencies of CD14 TT and T carrier were significantly higher in UC patients than in controls (TT: OR = 3.98, 95% CI 1.82-8.71, P = 0.0005; T carrier: OR = 2.98, 95% CI 1.47-6.01, P = 0.002). In addition, TT and T carrier were more closely associated with distal colitis phenotype (TT: OR = 7.78, 95% CI 2.14-28.28, P = 0.0007; T carrier: OR = 6.30, 95% CI 2.71-14.58, P = 0.005), onset after 20 years of age (TT: OR = 5.28, 95% CI 2.18-12.79; T carrier: OR = 3.79, 95% CI 1.67-8.59), chronic continuous type (TT: OR = 4.26, 95% CI 1.56-11.64; T carrier: OR = 3.09, 95% CI 1.33-7.82), and fewer than two hospitalizations (TT: OR = 4.44, 95% CI 1.81-10.89; T carrier: OR = 3.26, 95% CI 1.43-7.27). There was no significant difference in TLR2 -196 to -174 del/del and del/ins carrier frequencies between UC patients and healthy controls. However, these frequencies were significantly higher in steroid-dependant patients than in controls (del/del: OR = 6.08, 95% CI 1.41-26.21; del carrier: OR = 3.00, 95% CI 1.13-7.98). CONCLUSION: The results suggest that existence of a mutation in the CD14 gene is associated with an increased susceptibility to developing UC, especially chronic continuous distal colitis phenotypes that develop after 20 years of age. Furthermore, polymorphism of TLR2 may be related to an increased risk of intensive types such as steroid-dependent patients.  相似文献   

18.
Summary Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic patients share many clinical and biochemical characteristics. However, sural nerve biopsies from patients with advanced and chronic neuropathy show ultrastructural differences between these two groups. We investigated whether at a subclinical stage of the illness, when Type 1 and Type 2 diabetic patients are clinically uniform and the histopathological nerve alterations are not advanced, comparison between the two diabetes groups might show differences in nerve fibre involvement related to the different pathogeneses of the neuropathies. A total of 88 diabetic patients (52 Type 1 and 36 Type 2), with a subclinical form of polyneuropathy were selected. The clinical neurophysiological examination consisted of motor and sensory nerve conduction studies, Hoffmann (H)-reflex, single fibre electromyography and static as well as dynamic pupillometry. With regard to clinical neurophysiological abnormalities, the severity of the polyneuropathy appeared to be equal in both groups. Despite the absence of clinical symptoms the neurophysiological abnormalities were pronounced and it was impossible to differentiate Type 1 diabetic patients from Type 2 diabetic patients on a clinical neurophysiology basis when correcting for differences in age, height, and duration of illness. In the Type 1 diabetic group as well as in the Type 2 diabetic group the autonomic nerve fibres and nerves in the legs were more frequently affected than the thick myelinated nerves in the arms. These findings do not support the assumption that there is a difference in the manifestation of polyneuropathy between Type 1 and Type 2 diabetic patients.  相似文献   

19.
Summary A recent report has shown an association between a specific Xba1 restriction fragment of the human HepG2-Erythrocyte glucose transporter gene and Type 2 (non-insulin dependent) diabetes. To further examine the significance of this finding we have studied Type 2 diabetic pedigrees for linkage between the Xba1 alleles of this glucose transporter gene and diabetes. One large pedigree, in which the diabetic phenotype was associated with obesity and insulin resistance, was informative. In this family the disease did not co-segregate with the glucose transporter locus. Formal linkage analysis was performed assuming autosomal dominant inheritance with age-dependent penetrance. At putative gene frequencies of 0.01 and 0.001 the logarithin of the odds for linkage versus non-linkage at a recombination fraction of 0.001 was –1.84 and –3.32 respectively (a value of <-2 indicates definite non-linkage). Genetic variations in the HepG2-Erythrocyte glucose transporter gene are unlikely to be responsible for the development of diabetes in this pedigree.  相似文献   

20.
This work describes the mathematical modeling of the thermal decomposition of the complex compound [Ni(En)3](ClO4)2 (En = C2H8N2 = ethylenediamine) in an inert atmosphere under non-isothermal conditions. This process is characterized by several simultaneous and intense stages: elimination of ethylenediamine from the nickel coordination sphere, decomposition of perchlorate anions, and explosive-like oxidation of free or bound ethylenediamine. These stages overlap and merge into a one step on the differential thermogravimetric curve. Typically, this curve is modeled as a one-stage process during kinetic analysis. In this paper, for the first time, the data from the dynamic mass-spectral thermal analysis and thermogravimetric analysis were modeled using the hybrid genetic algorithm, and the results were compared. A two-stage scheme of [Ni(En)3](ClO4)2 thermolysis was proposed and the kinetic parameters for each stage were obtained. It was shown that the decomposition of [Ni(En)3](ClO4)2 begins with the elimination of one molecule of ethylenediamine (stage A), then the perchlorate anions quickly decompose with the evolution of oxygen (stage B). We believe that the resulting ClO4x (x = 1–3), as stronger oxidizing agents, instantly start an explosive-like exothermic process of ethylenediamine oxidation (stage B).  相似文献   

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