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1.
《Saudi Journal of Biological Sciences》2017,24(1):139-148
PurposeTo observe the effect of cynomorium total flavone on the depression model of perimenopausal rat and to analyze the action characteristics of cynomorium total flavone on depression of rat with perimenopausal syndrome.MethodDuplicate the model of rat with perimenopausal depression based on the combined method of incomplete castration and chronic stimulation, and keep drug administration for 35d. And then measure related behavior indicators and the change of biochemical index level in serum and brains; measure the estrogen/androgen receptor (ER/AR) in related tissues and the ERmRNA expression in hypothalamus.ResultIt can be seen that cynomorium total flavone can significantly improve the behavior indicators of rat with perimenopausal depression; obviously or significantly change the level of related biomedical indexes in serum and brains of perimenopausal depressed rat; obviously or significantly increase the expression of ER/AR in related tissues of perimenopausal depressed rat; obviously or significantly increase the ERmRNA expression in hypothalamus.ConclusionCynomorium total flavone can adjust hypothalamic-pituitary-gonadal axis by increasing E2, and make related biomedical indexes and hormone receptors tend to be normal, so as to relieve perimenopausal syndrome and perimenopausal syndrome with depression. 相似文献
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《Bioorganic & medicinal chemistry》2014,22(21):6174-6182
Upon reacting 3′,4′-unsaturated cytosine (8 and 9) and adenine nucleosides (13 and 14) with XeF2/BF3·OEt2, the respective novel 3′,4′-difluoro-3′-deoxyribofuranosyl nucleosides (10–12 and 15–18) could be obtained. Formation of anti-adducts (11, 16 and 18) revealed that the fluorination involved oxonium ions as incipient intermediates. TBDMS-protected 3′,4′-unsaturated adenosine provided the β-face adducts as sole stereoisomers whereas α-face-selectivity was observed with the TBDPS-protected adenosine 14. The evaluation of the novel 3′-deoxy-3′,4′-difluororibofuranosylcytosine-(19–21) and adenine nucleosides (22–25) against antitumor and antiviral activities revealed that 3′,4′-difluorocordycepin (24) was found to possess anti-HCV activity. The SI of 24 was comparable to that of the anti-HCV drug ribavirin. However, sofosbuvir, FDA-approved novel anti-HCV drug, showed better SI value. Our finding revealed that the introduction of the fluoro-substituent into the 4′-position of cordycepin derivatives decreased the cytotoxicity to the host cell with retention of the antiviral activity. 相似文献
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《Animal : an international journal of animal bioscience》2019,13(1):136-143
Piglets can often suffer impaired antioxidant status and poor immune response during post-weaning, especially when chronic inflammation takes place, leading to lower growth rates than expected. Oral administration of dietary antioxidant compounds during this period could be a feasible way to balance oxidation processes and increase health and growth performance. The aim of the trial was to study the effects of an antioxidant feed supplement (melon pulp concentrate) that contains high concentration of the antioxidant superoxide dismutase (SOD) on inflammation, antioxidant status and growth performance of lipopolysaccharide (LPS) challenged weaned piglets. In total, 48 weaned piglets were individually allocated to four experimental groups in a 2×2 factorial design for 29 days. Two different dietary treatments were adopted: (a) control (CTR), fed a basal diet, (b) treatment (MPC), fed the basal diet plus 30 g/ton of melon pulp concentrate. On days 19, 21, 23 and 25 half of the animals within CTR and MPC groups were subjected to a challenge with intramuscular injections of an increasing dosage of LPS from Escherichia coli (serotype 0.55:B5) (+) or were injected with an equal amount of PBS solution (−). Blood samples were collected at the beginning of the trial and under the challenge period for interleukin 1β, interleukin 6, tumour necrosis factor α, haptoglobin, plasma SOD activity, total antioxidant capacity, reactive oxygen species, red blood cells and plasma resistance to haemolysis, and 8-oxo-7, 8-dihydro-2’-deoxyguanosine. Growth performance was evaluated weekly. A positive effect of melon pulp concentrate was evidenced on total antioxidant capacity, half-haemolysis time of red blood cells, average daily gain (ADG) and feed intake, while LPS challenge increased pro-inflammatory cytokines and haptoglobin serum concentrations, with a reduced feed intake and gain : feed (G : F). The obtained results show that oral SOD supplementation with melon pulp concentrate ameliorates the total antioxidant capacity and the half-haemolysis time in red blood cell of post-weaning piglets, with positive results on growing performance. 相似文献
6.
Rene Rodriguez-Gutierrez Jose Gerardo González Deven Parmar Farheen. Shaikh Pio Cruz-López 《Journal of lipid research》2022,63(7):100233
Saroglitazar, being a dual PPAR-α/γ agonist, has shown beneficial effect in diabetic dyslipidemia and hypertriglyceridemia. Fibrates are commonly used to treat severe hypertriglyceridemia. However, the effect of saroglitazar in patients with moderate to severe hypertriglyceridemia was not evaluated. We conducted a study to compare the efficacy and safety of saroglitazar (4 mg) with fenofibrate (160 mg) in patients with moderate to severe hypertriglyceridemia. This was a multicenter, randomized, double-blinded, double-dummy, active-control, and noninferiority trial in adult patients with fasting triglyceride (TG) levels of 500–1,500 mg/dl. The patients were randomized in a 1:1 ratio to receive daily dose of saroglitazar or fenofibrate for 12 weeks. The primary efficacy end point was the percent change in TG levels at week 12 relative to baseline. The study comprised of 41 patients in the saroglitazar group and 41 patients in the fenofibrate group. We found that the percent reduction from baseline in TG levels at week 12 was significantly higher in the saroglitazar group (least square mean = ?55.3%; SE = 4.9) compared with the fenofibrate group (least square mean = ?41.1%; SE = 4.9; P = 0.048). Overall, 37 treatment-emergent adverse events (AEs) were reported in 24 patients (saroglitazar: 13; fenofibrate: 11). No serious AEs were reported, and no patient discontinued the study because of AEs. We conclude that saroglitazar (4 mg) is noninferior to fenofibrate (160 mg) in reducing TG levels after 12 weeks of treatment, was safe, and well tolerated. 相似文献
7.
Keun-Hong Park 《Biotechnology letters》2002,24(17):1401-1406
A copolymer, including a Gly-Arg-Gly-Asp-Ser (GRGDS) sequence and sugar moieties, was synthesized for the culturing of parenchymal cells (hepatocytes). Hepatocyte cells attached to poly[N-p-vinylbenzyl-d-maltonamide-co-6-(p-vinylbenzamido)-hexanoic acid-GRGDS] [poly(VMA-co-VBRGD)]-coated dishes grew approximately 60% better than on other polymer-coated surface for 12 h. Also, about 80% greater albumin secretion (0.38 pg ml–1) and about 70% greater urea synthesis (0.495 pg ml–1) from hepatocytes were produced in this matrix as compared with unstimulated cells. The behaviour of hepatocytes on poly(VMA-co-VBGRGDS)-coated dishes was not distinct from those attached to a collagen. The conjugation of the adhesion molecules of the RGD peptide in the poly(VMA-co-VBGRGDS) copolymer therefore specifically interacts with integrin families on the hepatocyte cell membrane. 相似文献
8.
Subrata Mondal 《Computer methods in biomechanics and biomedical engineering》2013,16(16):1247-1257
AbstractOne of the major causes of implant loosening is due to excessive bone resorption surrounding the implant due to bone remodelling. The objective of the study is to investigate the effects of implant material and implant–bone interface conditions on bone remodelling around tibia bone due to total ankle replacement. Finite element models of intact and implanted ankles were developed using CT scan data sets. Bone remodelling algorithm was used in combination with FE analysis to predict the bone density changes around the ankle joint. Dorsiflexion, neutral, and plantar flexion positions were considered, along with muscle force and ligaments. Implant–bone interfacial conditions were assumed as debonded and bonded to represent non-osseointegration and fully osseointegration at the porous coated surface of the implant. To investigate the effect of implant material, three finite element models having different material combinations of the implant were developed. For model 1, tibial and talar components were made of Co–Cr–Mo, and meniscal bearing was made of UHMWPE. For model 2, tibial and talar components were made of ceramic and meniscal bearing was made of UHMWPE. For model 3, tibial and talar components were made of ceramic and meniscal bearing was made of CFR-PEEK. Changes in implant material showed no significant changes in bone density due to bone remodelling. Therefore, ceramic appears to be a viable alternative to metal and CFR-PEEK can be used in place of UHMWPE. This study also indicates that proper bonding between implant and bone is essential for long-term survival of the prosthetic components. 相似文献
9.
王学利 《中国野生植物资源》2001,20(4):17-18,25
用正交实验结果作方差分析表明:溶剂用量对试验结果有较显著的影响(a=0.10),提取温度对试验结果也有较大的影响,而提取时间对试验结果的影响不显著。喜树叶中水溶性糖的提取最优方案是A3C2B3,即溶剂用量为60ml,提取温度80℃,提取时间60min;喜树叶水溶性糖的提取最优方案是A2C2B1,即溶剂用量为40ml,提取温度80℃,提取时间20min。通过对喜树叶与枝的成对比较分析,叶与枝的水溶性糖含量无显著差异。 相似文献
10.
Ribonuclease (EC 2.7.7.17) activity in the obligate halophyte Suaeda maritima (L.) Dum. var. macrocarpa Moq. was studied in relation to salinity (increasing concentrations of NaCl) of incubation and growth media. In vitro, the addition of 50 to 400 m M NaCl did not affect ribonuclease activity. This result, which was also found for Phaseolus vulgaris , indicates that the hydrolase is insensitive to high saline concentrations. The subcellular distribution of RNase activity did not change significantly with the salinity of the medium or with the age of the plant. The microsomal ribonuclease activity expressed on a fresh weight basis represented in every case less than 6% of the total activity. After 23 days of culture, the absence of salt stimulated the activity of soluble ribonuclease in aerial parts of Suaeda ; inversely, the capacity of the enzyme was lower under optimal saline conditions (130 m M NaCl). This was also evidenced by transfer of whole plants from a non-saline to a saline medium. Such a saline shock caused a decrease followed by a stabilization of the capacity of ribonuclease from Suaeda . The influx of NaCl in the tissues lowered the activity of the hydrolase. 相似文献