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31.
Alterations in gene expression in vitamin D‐deficiency: Down‐regulation of liver Cyp7a1 and renal Oat3 in mice
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Holly P. Quach Keumhan Noh Stacie Y. Hoi Adrie Bruinsma Geny M.M. Groothuis Albert P. Li Edwin C.Y. Chow K. Sandy Pang 《Biopharmaceutics & drug disposition》2018,39(2):99-115
The vitamin D‐deficient model, established in the C57BL/6 mouse after 8 weeks of feeding vitamin D‐deficient diets in the absence or presence of added calcium, was found associated with elevated levels of plasma parathyroid hormone (PTH) and plasma and liver cholesterol, and a reduction in cholesterol 7α‐hydroxylase (Cyp7a1, rate‐limiting enzyme for cholesterol metabolism) and renal Oat3 mRNA/protein expression levels. However, there was no change in plasma calcium and phosphate levels. Appraisal of the liver revealed an up‐regulation of mRNA expressions of the small heterodimer partner (Shp) and attenuation of Cyp7a1, which contributed to hypercholesterolemia in vitamin D‐deficiency. When vitamin D‐sufficient or D‐deficient mice were further rendered hypercholesterolemic with 3 weeks of feeding the respective, high fat/high cholesterol (HF/HC) diets, treatment with 1α,25‐dihydroxyvitamin D3 [1,25(OH)2D3], active vitamin D receptor (VDR) ligand, or vitamin D (cholecalciferol) to HF/HC vitamin D‐deficient mice lowered the cholesterol back to baseline levels. Cholecalciferol treatment partially restored renal Oat3 mRNA/protein expression back to that of vitamin D‐sufficient mice. When the protein expression of protein kinase C (PKC), a known, negative regulator of Oat3, was examined in murine kidney, no difference in PKC expression was observed for any of the diets with/without 1,25(OH)2D3/cholecalciferol treatment, inferring that VDR regulation of renal Oat3 did not involve PKC in mice. As expected, plasma calcium levels were not elevated by cholecalciferol treatment of vitamin D‐deficient mice, while 1,25(OH)2D3 treatment led to hypercalcemia. In conclusion, vitamin D‐deficiency resulted in down‐regulation of liver Cyp7a1 and renal Oat3, conditions that are alleviated upon replenishment of cholecalciferol. 相似文献
32.
Groothuis JT Hopman MT 《Archives of physical medicine and rehabilitation》2007,88(12):317-1740; author reply 1741
33.
Joel Jakobsson Maria Bjerke Carl Johan Ekman Carl Sellgren Anette GM Johansson Henrik Zetterberg Kaj Blennow Mikael Landén 《Neuropsychopharmacology》2014,39(10):2349-2356
Bipolar disorder (BD) is characterized by mood swings between manic and depressive states. The etiology and pathogenesis of BD is unclear, but many of the affected cognitive domains, as well as neuroanatomical abnormalities, resemble symptoms and signs of small vessel disease. In small vessel disease, cerebrospinal fluid (CSF) markers reflecting damages in different cell types and subcellular structures of the brain have been established. Hence, we hypothesized that CSF markers related to small vessel disease may also be applicable as biomarkers for BD. To investigate this hypothesis, we sampled CSF from 133 patients with BD and 86 healthy controls. The concentrations of neurofilament light chain (NF-L), myelin basic protein (MBP), S100B, and heart-type fatty acid binding protein (H-FABP) were measured in CSF and analyzed in relation to diagnosis, clinical characteristics, and ongoing medications. Hereby we found an elevation of the marker of subcortical axonal damage, NF-L, in bipolar subjects. We also identified positive associations between NF-L and treatment with atypical antipsychotics, MBP and lamotrigine, and H-FABP and lithium. These findings indicate axonal damage as an underlying neuropathological component of bipolar disorder, although the clinical value of elevated NF-L remains to be validated in follow-up studies. The associations between current medications and CSF brain injury markers might aid in the understanding of both therapeutic and adverse effects of these drugs. 相似文献
34.
Characterization of the effects of cultured vascular cells on the activation of blood coagulation 总被引:9,自引:0,他引:9
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells. 相似文献
35.
贵池日本血吸虫对江苏沿海地区钉螺感染性的初步研究 总被引:1,自引:1,他引:1
目的 了解异地血吸虫品系对江苏省沿海残存钉螺的感染性。方法 用安徽省贵池现场感染性钉螺逸出的尾蚴感染家兔所取得的毛蚴 ,以毛蚴与钉螺 2 0∶ 1感染现场采集的钉螺 ,比较钉螺感染率和尾蚴逸出前期。结果 贵池血吸虫对如东、东台和贵池 3地钉螺感染率分别为 4 .35 %、16 .0 0 %和 4 0 .5 8% ,尾蚴平均逸出前期分别为 (72 .6 9± 8.73) d、(6 8.35± 5 .78) d和 (71.5 0± 9.0 7)d,贵池血吸虫对当地钉螺感染率显著高于对江苏沿海钉螺的感染率 (x1 2 =2 4 .5 8,x2 2 =14 .35 ,P <0 .0 1) ,尾蚴逸出前期差异无显著性 (t1 =0 .0 2 35 ,t2 =0 .1732 ,P>0 .1)。结论 江苏沿海地区钉螺在室内能被贵池血吸虫实验感染 ,长江流域血吸虫的输入 ,有可能导致血吸虫病的再流行 相似文献
36.
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients. 相似文献
37.
PG Kareru JM Keriko GM Kenji GT Thiong'o AN Gachanja HN Mukiira 《African journal of traditional, complementary, and alternative medicines》2010,7(3):214-218
In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus. 相似文献
38.
目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014~1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087~7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。 相似文献
39.
High initial drug resistance in pulmonary tuberculosis in Ghana 总被引:3,自引:0,他引:3
Between July 1985 and March 1987, initial sensitivity to anti-tuberculosis drugs was studied in patients presenting at the Chest Clinic of Agogo Hospital in the forest area of Ghana. Culture and sensitivity test results were obtained in 99 out of 123 consecutive patients with pulmonary tuberculosis who claim not to have received previous treatment. Isoniazid resistance was alarmingly high in the isolates of M. tuberculosis: 21 out of 57 (37%), and thiacetazone resistance was very high in the M. africanum isolates: 20 out of 42 (47%). Overall resistance was high: 27% to isoniazid, 23% to streptomycin, 29% to thiacetazone, 16% to both streptomycin and isoniazid, and 5% to all of these three drugs. Only 45% of the isolates were sensitive to all three drugs. Primary drug resistance to rifampicin, pyrazinamide or ethambutol was not observed. Besides the standard treatment of isoniazid, streptomycin and thiacetazone, rifampicin and pyrazinamide were usually added for the first two months of treatment. Of 13 patients who received standard treatment only, 4 of the 5 patients with resistant organisms who could be followed up failed to respond, whereas there were no failures to respond in the 5 corresponding patients with initially sensitive organisms; 3 patients could not be assessed because they defaulted. 相似文献
40.
KI Wheeler GM Schmölzer CJ Morley PG Davis 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):67-70
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency. 相似文献