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1.
Macrolide (R)-de-O-methyllasiodiplodin (1), discovered to be a potent nonsteroidal antagonist of the mineralocorticoid receptor (MR), was synthesized via an efficient method and evaluated for MR antagonistic activity together with its analogs. Among all the tested compounds, compounds 18a, 18b and 18c, exhibited more potent antagonistic activity against MR with IC50 values ranging from 0.58 to 1.11 μM. Generally, it was obviously demonstrated that acetylation at phenolic hydroxyl groups and the ring size in analogs of 1 were very important for MR antagonist activity.  相似文献   

2.
Series of new sulfonylurea derivatives (gliclazide analogues) was synthesized and characterized. Thus, p-tolylsulfonylisocyanate was left to react with different amino derivatives under mild conditions to afford the desired sulfonylurea derivatives 15. The molecular structure of the compound N-(2,6-Dichlorophenylcarbamoyl)-4-methylbenzenesulfonamide, 1c has been elucidated by single crystal X-ray diffraction. Anti-diabetic properties of the synthesized compounds relative to anti-diabetic drug (gliclazidem MR60) were carried out, where most of the tested compounds showed significant activity for reducing the blood glucose level. The results revealed that compounds 1c and 5 showed better anti-diabetic activities compared with gliclazide. Activity of the most potent derivatives of sulfonylurea compounds namely 1c and 5 were increased using coated nanostructure tetraethyl orthosilicate (TEOS) as a modified release (MR) agent. The effect of the prepared sulfonylurea compounds against the diabetic condition was investigated using specific selected biomarkers as of liver enzyme activities as transaminases (AST, ALT) and alkaline phosphatase (ALP), lipids profiles; total cholesterol (TC), triacylglycerols (TG) and total lipid (TL). The antioxidants, oxidative stress biomarkers and histological examination were also examined and discussed.  相似文献   

3.
Cephalotrichum microsporum (SYP-F 7763) was a fungus isolated from the rhizosphere soil of traditional Chinese medicine Panax notoginseng. The EtOAc extract of Cephalotrichum microsporum cultivated on sterilized moistened-rice medium was separated by various chromatographic techniques, which yielded 11 metabolites (1–11) of this fungus. On the basis of the widely spectroscopic data, the chemical structures of isolated metabolites were determined, most of which were α-pyrones, including 5 compounds (4–7, and 10) unreported. In the anti-bacterial bioassay, compound 1 displayed significant inhibitory effects on three pathogenic bacteria, MR S. aureus, S. aureus, and B. cereus. α-Pyrones 2, 3, and 5–7 also displayed moderate inhibitory effects on MR S. aureus, S. aureus, and B. subtilis, which could be the major anti-bacterial constituents of Cephalotrichum microsporum. Additionally, compounds 1, 4, and 5 displayed significant cytotoxicity on five human cancer cell lines, with the IC50 values < 20 μM, which are more effective than positive control 5-fluorouracil. Therefore, α-pyrones were important secondary metabolites of Cephalotrichum microsporum, which displayed anti-bacterial and anti-tumor activities.  相似文献   

4.
In the course of our study on selective nonsteroidal mineralocorticoid receptor (MR) antagonists, a series of novel benzoxazine derivatives possessing an azole ring as the core scaffold was designed for the purpose of attenuating the partial agonistic activity of the previously reported dihydropyrrol-2-one derivatives. Screening of alternative azole rings identified 1,3-dimethyl pyrazole 6a as a lead compound with reduced partial agonistic activity. Subsequent replacement of the 1-methyl group of the pyrazole ring with larger lipophilic side chains or polar side chains targeting Arg817 and Gln776 increased MR binding activity while maintaining the agonistic response at the lower level. Among these compounds, 6-[1-(2,2-difluoro-3-hydroxypropyl)-5-(4-fluorophenyl)-3-methyl-1H-pyrazol-4-yl]-2H-1,4-benzoxazin-3(4H)-one (37a) showed highly potent in vitro activity, high selectivity versus other steroid hormone receptors, and good pharmacokinetic profiles. Oral administration of 37a in deoxycorticosterone acetate-salt hypertensive rats showed a significant blood pressure-lowering effect with no signs of antiandrogenic effects.  相似文献   

5.
Synthesis and structure–activity relationship (SAR) of a series of alkyl and cycloalkyl containing non-steroidal dissociated glucocorticoid receptor (GR) agonists is reported. This series of compounds was identified as part of an effort to replace the CF3 group in a scaffold represented by 1a. The study culminated in the identification of compound 14, a t-butyl containing derivative, which has shown potent activity for GR, selectivity against the progesterone receptor (PR) and the mineralocorticoid receptor (MR), in vitro anti-inflammatory activity in an IL-6 transrepression assay, and dissociation in a MMTV transactivation counter-screen. In a collagen-induced arthritis mouse model, 14 displayed prednisolone-like efficacy, and lower impact on body fat and free fatty acids than prednisolone at an equivalent anti-inflammatory dose.  相似文献   

6.
Male Holstein calves commonly receive minimal quantities of milk replacer (MR) to speed up weaning and reduce costs. Studies with Holstein female calves show that early life feed restriction affects energy metabolism later in life. Aiming to test this hypothesis, 120 Holstein bull calves (48.4 ± 2.2 kg of BW and 20 ± 3.2 d of age) housed in 24 pens were blocked and randomized to two treatments: A low calf MR allowance (LP) (two daily doses of 2 l each, 582 g/d of DM), or a high MR allowance (HP) (two daily meals of 4 l each, 1 164 g/d of DM). Calves were weaned at day 49 of the study and slaughtered at 32.8 ± 0.5 weeks of age. Throughout the study, animals had ad libitum access to a common compound feed, straw, and water. Twenty-four animals were randomly selected for an intravenous glucose tolerance test (IVGTT). The IVGTT was performed at week 6 and 12 of the study and consisted of an intravenous glucose infusion and sequential blood sampling up to 90 min after glucose infusions. Calves were heavier for HP until week 12, after which the difference disappeared. By design, the MR intake was higher in the HP group resulting in a higher energy intake and a higher average daily gain in the preweaning phase. Blood glucose curves were not different at week 6, but at week 12, 5 min after the infusion, glucose was higher in HP calves. Insulin curves were not different at week 6. Nevertheless, in week 12, a higher insulin concentration was observed for HP 5, 10, 15, 20, 30, 35, and 45 min’ postinfusion, indicating a higher requirement of insulin to control glycemia. Differences between HP and LP calves were also observed for the quantitative insulin sensitivity check index, maximum insulin concentration, and insulin delta at week 12. Blood glucose reached maximum concentration within 5–10 min of the IVGTT test, and the concentration was, on average, 8.58 and 10.80 mmol/l at weeks 6 and 12, respectively. Insulin reached maximum concentration within 10–15 min of the IVGTT, and concentrations were, on average, 33.32 and 32.61 μUI/ml at weeks 6 and 12, respectively. Doubling MR supply improved animal growth up to weaning, but these differences disappeared by the end of the feeding period. Despite similar responses to glucose infusions preweaning, higher milk supply seemed to decrease insulin sensitivity after weaning.  相似文献   

7.
Dihydrofuran-2-one and dihydropyrrol-2-one derivatives were identified as novel, potent and selective mineralocorticoid receptor (MR) antagonists by the structure-based drug design approach utilizing the crystal structure of MR/compound complex. Introduction of lipophilic substituents directed toward the unfilled spaces of the MR and identification of a new scaffold, dihydropyrrol-2-one ring, led to potent in vitro activity. Among the synthesized compounds, dihydropyrrol-2-one 11i showed an excellent in vitro activity (MR binding IC50 = 43 nM) and high selectivity over closely related steroid receptors such as the androgen receptor (AR), progesterone receptor (PR) and glucocorticoid receptor (GR) (>200-fold for AR and PR, 100-fold for GR).  相似文献   

8.
9.
Short-term nutrient restrictions can occur naturally in extensive beef cattle production systems due to low feed quality or availability. The aims of the study were to (1) model the curves of milk yield, plasma non-esterified fatty acids (NEFAs) and β-hydroxybutyrate (BHB) contents of beef cows in response to short nutritional challenges throughout lactation; (2) identify clusters of cows with different response profiles; (3) quantify differences in cows’ response between the clusters and lactation stages. Data of BW, body condition score (BCS), milk yield, NEFA, and BHB plasma concentration from 31 adult beef cows (626 ± 48 kg at calving) were used to study the effect of 4-day feed restriction repeated over months 2, 3 and 4 of lactation. On each month, all cows received a single diet calculated to meet the requirements of the average cow: 100 % requirements for 4 days (d-4 to d-1, basal period), 55 % requirements on the next 4 days (d0 to d3, restriction period) and 100 % requirements for 4 days (d4 to d7, refeeding period). Natural cubic splines were used to model the response of milk yield, NEFA and BHB to restriction and refeeding in the 3 months. The new response variables [baseline value, peak value, days to peak and to regain baseline, and areas under the curve (AUC) during restriction and refeeding] were used to cluster cows according to their metabolic response (MR) into two groups: Low MR and High MR. The month of lactation affected all the traits, and basal values decreased as lactation advanced. Cows from both clusters had similar BW and BCS values, but those in the High MR cluster had higher basal milk yield, NEFA and BHB contents, and responded more intensely to restriction, with more marked peaks and AUCs. Reaction times were similar, and baseline values recovered during refeeding in both clusters. Our results suggest that the response was driven by cows’ milk potential rather than size or body reserves, and despite high-responding cattle’s higher milk yield, they were able to activate metabolic pathways to respond to and recover from the challenge.  相似文献   

10.
《Endocrine practice》2018,24(1):91-121
Abbreviations: A1C = hemoglobin A1C; AACE = American Association of Clinical Endocrinologists; ACCORD = Action to Control Cardiovascular Risk in Diabetes; ACCORD BP = Action to Control Cardiovascular Risk in Diabetes Blood Pressure; ACEI = angiotensin-converting enzyme inhibitor; ADVANCE = Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation; AGI = alpha-glucosidase inhibitor; apo B = apolipoprotein B; ASCVD = atherosclerotic cardiovascular disease; BAS = bile acid sequestrant; BCR-QR = bromocriptine quick release; BMI = body mass index; BP = blood pressure; CCB = calcium channel blocker; CHD = coronary heart disease; CKD = chronic kidney disease; CVD = cardiovascular disease; DASH = Dietary Approaches to Stop Hypertension; DPP4 = dipeptidyl peptidase 4; eGFR = estimated glomerular filtration rate; ER = extended release; FDA = Food and Drug Administration; GLP1 = glucagon-like peptide 1; HDL-C = high-density lipoprotein cholesterol; IMPROVE-IT = Improved Reduction of Outcomes: Vytorin Efficacy International Trial; LDL-C = low-density lipoprotein cholesterol; LDL-P = low-density lipoprotein particle; Look AHEAD = Look Action for Health in Diabetes; NPH = neutral protamine Hagedorn; OSA = obstructive sleep apnea; RCT = randomized controlled trial; SU = sulfonylurea; SGLT2 = sodium glucose cotransporter-2; SMBG = self-monitoring of blood glucose; T2D = type 2 diabetes; TZD = thiazolidinedione; VADT = Veterans Affairs Diabetes Trial  相似文献   

11.
A class of arylsulfonamide glucocorticoid receptor agonists that contains a substituted phenyl group as a steroid A-ring mimetic is reported. The structural design and SAR that provide the functional switching of a GR antagonist to an agonist is described. A combination of specific hydrogen bonding and lipophilic elements on the A-ring moiety is required to achieve potent GR agonist activity. This study culminated in the identification of compound 23 as a potent GR agonist with selectivity over the PR and MR nuclear hormone receptors.  相似文献   

12.

Background

Cerebral venous sinus thrombosis (CVST) is a relatively rare cerebrovascular condition which accounts for 0.5% of all strokes. Risk of CVST has been documented in patients with numerous conditions including central nervous system infections, however, Japanese encephalitis (JE, epidemic encephalitis type B) with CVST has not been reported previously.

Case Presentation

Here, we present a case of JE with CVST in a 17-year-old man. On admission, the patient was initially diagnosed as intracranial infection, and soon after, brain magnetic resonance (MR) imaging (MRI) and MR Venography (MRV) confirmed the diagnosis of CVST. Moreover, the blood JE-specific IgM antibody which proved weakly positive at first, turned positive one week later. Consequently, our patient was diagnosed as CVST accompanied by JE. Anticoagulant and anti-infective therapy were initiated, which eventually lead to gradual recovery of the patient.

Conclusions

To our knowledge, this is the first case report of CVST associated with JE. MRI and MRV represent a prime method for the diagnosis of CVST, while the positivity of JE virus IgM antibody, especially increased antibody levels within a short period, is of great significance to diagnose JE. The early diagnosis and timely treatment of this potentially lethal condition would improve its prognosis significantly.  相似文献   

13.
A binary targeting vector that consists of peptide sequences of Arg-Gly-Asp (RGD) and Asn-Gly-Arg (NGR) motifs has been designed and synthesized using solid-phase peptide synthesis procedure. The vector is then coupled with Gd-DOTA to work as a targeting contrast agent (CA1) for magnetic resonance imaging of human lung adenocarcinoma cells A549. Its longitudinal relaxivity is measured to be 7.55 mM?1 s?1 in aqueous solution at a magnetic field of 11.7 T, which is higher than that of Magnevist (4.25 mM?1 s?1) in the same conditions. The cell experiment shows, at the same concentration, uptake quantity of CA1 by A549 is much more than Magnevist and also superior over CA2 (a single targeting contrast agent contains only RGD). The uptake can be blocked by the targetable peptide containing RGD or NGR without coupling Gd. To summarize, CA1 has very good ability to target A549 and higher relaxivity than that of Magnevist. So CA1 is promising MRI contrast agent for high-resolution MR molecular imaging of human lung adenocarcinoma A549 cells.  相似文献   

14.
A number of hydroxylated diterpenoids were obtained from the microbial transformation of isosteviol lactone (4α-carboxy-13α-hydroxy-13,16-seco-ent-19-norbeyeran-16-oic acid 13,16-lactone) (2) with Mucorrecurvatus MR 36, Aspergillusniger BCRC 31130, and Absidiapseudocylindrospora ATCC 24169. Incubation of 2 with M. recurvatus and Asp.niger led to isolation of seven known compounds (1 and 3-8). Incubation of 2 with Abs. pseudocylindrospora produced 5 and six previously unreported compounds (9-14). The structures of these isolated compounds were deduced by high-field NMR techniques (1H, 13C, DEPT, COSY, NOESY, HSQC, and HMBC), and those of 9 and 11 were further confirmed by X-ray crystallographic analyses. Subsequently, the inhibitory effects on activator protein-1 (AP-1) activation in lipopolysaccharide-stimulated RAW 264.7 macrophages of all of these compounds were evaluated. Compounds 2-5, 8, 9, 11, and 12 exhibited significant inhibitory activity, while 3 was more potent than the reference compound of dexamethasone.  相似文献   

15.
《Endocrine practice》2016,22(5):575-586
Objective: To assess 12-month body weight (BW) and body composition changes in normoglycemic women with midlife weight gain, after dietary and pharmacologic interventions targeting hyperinsulinemia.Methods: EMPOWIR (Enhance the Metabolic Profile of Women With Insulin Resistance; NCT00618072) was a double-blind, placebo-controlled, 12-month trial of women with >20-pound weight gain, normal glucose tolerance test, and increased area-under-the-curve insulin. Subjects (mean ± SD, 46.7 ± 6.5 years of age; body mass index, 30.8 ± 2.8 kg/m2; 50% white) attended 4 nutrition workshops to introduce a novel carbohydrate-modified diet (CMD) and were then randomized to one of three arms for 6 months (phase 1): CMD alone (D), or in combination with metformin (M), or metformin + rosiglitazone (MR), with rerandomization of the D group to one of the active treatment arms (phase 2, months 7 through 12). Repeated measure analysis of variance was used to assess BW at baseline, 6 months, and 12 months in 32 subjects with 12-month data; paired t tests compared baseline and 12-month dual-energy X-ray absorptiometry–derived body composition.Results: Mean (±SD) BW decreased significantly at 12 months in the M arm: 85.1 ± 8.5 kg to 79.8 ± 9.0 kg (P = .0003), with 54% of variance in weight over time explained by M treatment. Mean (±SD) percent android fat decreased significantly in the M and D arms: 53.5 ± 4.8% to 49.3 ± 7.6% (P = .010) and 52.9 ± 6.2% to 48.1 ± 8.7% (P = .021).Conclusion: In combination with a novel carbohydrate modified diet, metformin enhanced 12-month weight loss and improved body composition in ethnically diverse normoglycemic, hyperinsulinemic women with midlife weight gain. These findings suggest that EMPOWIR's easily implemented dietary interventions, alone and in combination with pharmacotherapies that target hyperinsulinemia, merit additional investigation in larger, long-term studies.Abbreviations:ANOVA = analysis of varianceBC = body compositionBW = body weightCMD = carbohydrate-modified dietD = diet alone groupDXA = dual-energy X-ray absorptiometryEMPOWIR = Enhance the Metabolic Profile of Women With Insulin ResistanceM = metformin groupMR = metformin + rosiglitazone group  相似文献   

16.
《Endocrine practice》2013,19(6):928-936
ObjectiveWe investigated the relationship between postoperative glucose levels (days 1 through 3) and immediate outcomes in patients who underwent isolated coronary artery bypass grafting (CABG).MethodsWe conducted a retrospective study of 2,558 consecutive patients who had isolated CABG. Patients were stratified into 3 groups based on their pre-operative mortality risk (MR), using Society of Thoracic Surgeons’ criteria. Average glucose levels for the first 3 days following surgery were determined. Glucose levels for each group were divided into quartiles and related to relevant outcomes. Odds ratios assessing changes in outcomes as functions of increased glucose exposure were determined for postoperative days 1, 2, and 3 and for postoperative days 1 and 2 and 1 through 3.ResultsThe number of patients in each MR group (1 through 3; low, medium, and high) was 1,233, 852, and 473, respectively. Mean ± SD quartile glucose levels for days 1 and 2 were 133 ± 8.2, 150.4 ± 4.7, 167.2 ± 6.89, and 205.9 ± 24.9 mg/dL. The proportion of patients with a glucose level <70 mg/dL was 6.4%, <60 mg/dL was 2.7%, and <50 mg/dL was 1.1%.The most consistent and significant correlations between glucose quartiles and outcomes were observed for MR group 1, and they were most significant for the first 2 days following surgery. Glycemic control was not correlated with mortality, but it was correlated with total complications.ConclusionHyperglycemia during the first two days after CABG adversely affected total complications in patients who were in the low and medium MR groups, but it did not significantly affect hospital mortality. (Endocr Pract. 2013;19:928-936)  相似文献   

17.
《IRBM》2022,43(6):549-560
Objectives: In recent times, MR image is used to detect the dementia diagnostic differences in preclinical stages. Mild cognitive impairment (MCI) is characterized by slight cognitive deficits. This can be categorized into early and late mild cognitive impairment according to extent of episodic cognitive impairment. There is a higher risk of MCI subject to convert into Alzheimers disease. It is observed that there is no appropriate biomarker to find severity changes in dementia. Thus, this work aims to identify appropriate biomarker using radiomic and hybrid social algorithms.Materials: ADNI database is utilized for this study. Grey matter, cerebrospinal fluid, ventricle, hippocampus, brain stem and mid brain regions are examined to extract the radiomic features. This provides local and global tissue changes of these regions. The significant features are obtained using hybrid salp swarm and particle swarm optimization method (SSA-PSO). SVM is adopted to classify the normal and severity groups. The performance of work is validated clinically and statistically.Results: Results show that radiomic features capture anatomical changes for considered regions. The significant features from SSA-PSO show greater causal association and statistical significance for all considered regions. However, hippocampus achieves 88.5% of classification accuracy than other regions in the considered group. The inter class variations of hippocampus gives precise prognosis differences. From the clinical validation, it is also found that the obtained result show high statistical significance (p<0.0001) among the different severity.Conclusion: The proposed work shows promising results in using these biomarkers in detection of dementia and support clinical decisions.  相似文献   

18.
Chemical study of Piper crocatum leaves has led to isolation of a new megastigmane glucoside isomer (18), along with 23 known compounds including fifteen phenolic compounds (115), two monoterpenes (16 and 17), three sesquiterpenes (1921), a phenolic amide glycoside (22), a neolignan (23), and a flavonoid C-glycoside (24). Structures of these compounds were identified via spectroscopic methods and compared with those reported in the literature. Seven compounds (7, 11, 13, 14, 17, 20, and 24) from the P. crocatum species and 17 others (16, 810, 12, 1516, 1819, and 2123) from the Piper genus and Piperaceae family were isolated and reported for the first time. Furthermore, this study discusses chemotaxonomic relations between P. crocatum and other Piper species.  相似文献   

19.
Poor performance and ill-health of calves in the pre-wean period can affect future productivity. Increasing numbers of producers are opting to use calf jackets as a means of mitigating the potential negative effects of low ambient temperatures, wind speed and precipitation on growth and health. This study aimed to use a range of noninvasive monitoring technologies to investigate the effects of using calf jackets in the first 3 weeks of life on calf performance and behavioural and physiological parameters. Ninety Holstein-Friesian calves were allocated to one of the two treatments: (i) Jacketed until 21 days of age and (J; n = 44) ii. Nonjacketed (NJ; n = 46). Calves were group housed and fed milk replacer (MR) and concentrate solid feed via automatic feeders. Calves were weaned at day 56, and the experiment was completed at day 63. Health assessments were conducted on a daily basis throughout the experiment using predefined faecal and respiratory scoring protocols. A range of novel, noninvasive monitoring technologies were used to examine the activity, heart rate and thermal profiles of calves on an individual basis throughout the experimental period. There were no differences in calf live weight (LWT), average daily gain (ADG) or feed conversion efficiency (FCE) in J and NJ calves between days 5 to 20. However, NJ calves consumed more MR and had more unrewarded visits to the milk feeder than J calves during this period. Although calf LWT was comparable across treatments in the week following jacket removal (days 21 to 28), both ADG and FCE tended to be greater in NJ calves. There were no treatment differences in calf LWT at the end of the study (d63). When measured over a period of 24 h and at a mean ambient temperature of 7.7°C, skin surface temperature was 6.37°C higher in J calves. Core body temperature was higher in J calves between days 5 to 20; however, there were no differences in IR eye or IR rectal temperature. No differences in lying behaviour occurred, with calves spending 18 and 17 h/day lying between days 5 to 20 and days 21 to 28, respectively. Under the climatic and management conditions described, no significant benefits to calf performance were found as a result of the provision of calf jackets to group-housed calves in the first 3 weeks of life. The higher frequency of unrewarded visits to the milk feeder in NJ calves during the first 3 weeks of life could be suggestive of a lack of satiety in these calves.  相似文献   

20.
Processive phytochemistry and pharmacological investigation of Schefflera leucantha R.Vig. (Araliaceae) led to the isolation of fifteen known compounds: a nucleobase (1), six small aromatic molecules (27), three phenylpropanoids (8–10), four lignans (1114) and a fatty acid derivative (15). Spectroscopic methods were used to establish the structure and configuration of isolates, followed by their unambiguous confirmation with literature data. We report for the first time (to the best of our knowledge), the isolation of β-amino-3-methoxy-4-hydroxybenzene-ethanol (4) from a natural source. Furthermore, compounds 1, 5, 915 are being reported from Araliaceae family for the first time, whereas compounds 2, 3, 68 from the genus Schefflera for the first time. The biological screening results show that compounds 9 and 10 induce a moderate inhibitory effect on aldose reductase, while compounds 3, 5, and 8 display significantly high neuroprotective activities.  相似文献   

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