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1.
Botulinum toxin injection on epicardial fat, which inhibits acetylcholine (ACh) release, reduced the presence of atrial fibrillation (AF) in patients after heart surgery. Thus, we wanted to study the profile of the released proteins of epicardial adipose tissue (EAT) under cholinergic activity (ACh treatment) and their value as AF predictors. Biopsies, explants, or primary cultures were obtained from the EAT of 85 patients that underwent open heart surgery. The quantification of muscarinic receptors (mAChR) by real-time polymerase chain reaction or western blot showed their expression in EAT. Moreover, mAChR Type 3 was upregulated after adipogenesis induction (p < 0.05). Cholinergic fibers in EAT were detected by vesicular ACh transporter levels and/or acetylcholinesterase activity. ACh treatment modified the released proteins by EAT, which were identified by nano-high-performance liquid chromatography and TripleTOF analysis. These differentially released proteins were involved in cell structure, inflammation, or detoxification. After testing the plasma levels of alpha-defensin 3 (inflammation-involved protein) of patients who underwent open heart surgery ( n = 24), we observed differential levels between the patients who developed or did not develop postsurgery AF (1.58 ± 1.61 ng/ml vs. 6.2 ± 5.6 ng/ml; p < 0.005). The cholinergic activity on EAT might suggest a new mechanism for studying the interplay among EAT, autonomic nervous system dysfunction, and AF.  相似文献   

2.
Nicotinamide N‐methyltransferase (NNMT) plays a central role in cellular metabolism, regulating pathways including epigenetic regulation, cell signalling, and energy production. Our previous studies have shown that the expression of NNMT in the human neuroblastoma cell line SH‐SY5Y increased complex I activity and subsequent ATP synthesis. This increase in ATP synthesis was lower than the increase in complex I activity, suggesting uncoupling of the mitochondrial respiratory chain. We, therefore, hypothesised that pathways that reduce oxidative stress are also increased in NNMT‐expressing SH‐Y5Y cells. The expression of uncoupling protein‐2 messenger RNA and protein were significantly increased in NNMT‐expressing cells (57% ± 5.2% and 20.1% ± 1.5%, respectively; P = .001 for both). Total GSH (22 ± 0.3 vs 35.6 ± 1.1 nmol/mg protein), free GSH (21.9 ± 0.2 vs 33.5 ± 1 nmol/mg protein), and GSSG (0.6 ± 0.02 vs 1 ± 0.05 nmol/mg protein; P = .001 for all) concentrations were significantly increased in NNMT‐expressing cells, whereas the GSH:GSSG ratio was decreased (39.4 ± 1.8 vs 32.3 ± 2.5; P = .02). Finally, reactive oxygen species (ROS) content was decreased in NNMT‐expressing cells (0.3 ± 0.08 vs 0.12 ± 0.03; P = .039), as was the concentration of 8‐isoprostane F2α (200 ± 11.5 vs 45 ± 2.6 pg/mg protein; P = .0012). Taken together, these results suggest that NNMT expression reduced ROS generation and subsequent lipid peroxidation by uncoupling the mitochondrial membrane potential and increasing GSH buffering capacity, most likely to compensate for increased complex I activity and ATP production.  相似文献   

3.
IntroductionEpicardial exit sites of ventricular tachycardia (VT) are frequently encountered during VT ablation requiring an epicardial ablation approach for successful elimination of VT. We sought to assess the utility of repolarization markers in identifying individuals requiring an epicardial ablation approach in addition to an endocardial approach.Methods32 patients who underwent successful ablation for scar mediated VT were included in the study. Fourteen patients who required a combined endocardial and epicardial VT ablation were defined as epicardial VT group (Epi) whereas 18 patients who were successfully ablated from the endocardium alone constituted the endocardial VT group (Endo). Repolarization markers during sinus rhythm were compared between the two groups.ResultsA higher QTc max and QTc dispersion were seen in the Epi group compared to Endo group (479 ± 34 vs 449 ± 20, p = 0.008 and 63 ± 13 vs 38 ± 8, p = 0.001, respectively). Ts-p and Ts-p/Tp-e were higher in the Epi group (166 ± 23 vs 143 ± 23, p = 0.008 and 1.55 ± 0.26 vs 1.3 ± 0.21, p < 0.005). On multivariate regression, QTc dispersion was an independent predictor of the need for an epicardial approach to ablation. A QTc dispersion more than 51.5 msec identified individuals requiring a combined epicardial and endocardial approach to ablation with a sensitivity of 92.9% and a specificity of 100%.ConclusionsPatients requiring an epicardial ablation have a higher QTc dispersion. A value greater than 51.5 msec reliably differentiates between the two groups with high sensitivity and specificity.  相似文献   

4.
We tested the hypothesis that superoxide signaling within aortic perivascular adipose tissue (PVAT) contributes to large elastic artery stiffening in old mice. Young (4–6 months), old (26–28 months), and old treated with 4‐Hydroxy‐2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPOL), a superoxide scavenger (1 mm in drinking water for 3 weeks), male C57BL6/N mice were studied. Compared with young, old had greater large artery stiffness assessed by aortic pulse wave velocity (aPWV, 436 ± 9 vs. 344 ± 5 cm s‐1) and intrinsic mechanical testing (3821 ± 427 vs. 1925 ± 271 kPa) (both P < 0.05). TEMPOL treatment in old reversed both measures of arterial stiffness. Aortic PVAT superoxide production was greater in old (P < 0.05 vs. Y), which was normalized with TEMPOL. Compared with young, old controls had greater pro‐inflammatory proteins in PVAT‐conditioned media (P < 0.05). Young recipient mice transplanted with PVAT from old compared with young donors for 8 weeks had greater aPWV (409 ± 7 vs. 342 ± 8 cm s‐1) and intrinsic mechanical properties (3197 ± 647 vs. 1889 ± 520 kPa) (both P < 0.05), which was abolished with TEMPOL supplementation in old donors. Tissue‐cultured aortic segments from old in the presence of PVAT had greater mechanical stiffening compared with old cultured in the absence of PVAT and old with PVAT and TEMPOL (both, P < 0.05). In addition, PVAT‐derived superoxide was associated with arterial wall hypertrophy and greater adventitial collagen I expression with aging that was attenuated by TEMPOL. Aging or TEMPOL treatment did not affect blood pressure. Our findings provide evidence for greater age‐related superoxide production and pro‐inflammatory proteins in PVAT, and directly link superoxide signaling in PVAT to large elastic artery stiffness.  相似文献   

5.
Myocardial hibernation (MH) is a well‐known feature of human ischaemic cardiomyopathy (ICM), whereas its presence in human idiopathic dilated cardiomyopathy (DCM) is still controversial. We investigated the histological and molecular features of MH in left ventricle (LV) regions of failing DCM or ICM hearts. We examined failing hearts from DCM (n = 11; 41.9 ± 5.45 years; left ventricle‐ejection fraction (LV‐EF), 18 ± 3.16%) and ICM patients (n = 12; 58.08 ± 1.7 years; LVEF, 21.5 ± 6.08%) undergoing cardiac transplantation, and normal donor hearts (N, n = 8). LV inter‐ventricular septum (IVS) and antero‐lateral free wall (FW) were transmurally (i.e. sub‐epicardial, mesocardial and sub‐endocardial layers) analysed. LV glycogen content was shown to be increased in both DCM and ICM as compared with N hearts (P < 0.001), with a U‐shaped transmural distribution (lower values in mesocardium). Capillary density was homogenously reduced in both DCM and ICM as compared with N (P < 0.05 versus N), with a lower decrease independent of the extent of fibrosis in sub‐endocardial and sub‐epicardial layers of DCM as compared with ICM. HIF1‐α and nestin, recognized ischaemic molecular hallmarks, were similarly expressed in DCM‐LV and ICM‐LV myocardium. The proteomic profile was overlapping by ~50% in DCM and ICM groups. Morphological and molecular features of MH were detected in end‐stage ICM as well as in end‐stage DCM LV, despite epicardial coronary artery patency and lower fibrosis in DCM hearts. Unravelling the presence of MH in the absence of coronary stenosis may be helpful to design a novel approach in the clinical management of DCM.  相似文献   

6.
Trimethylamine N‐oxide (TMAO) is an independent risk factor of cardiovascular disease. Our objective was to explore the relation between TMAO and ischemic stroke (IS) in patients with atrial fibrillation (AF). A total of 68 patients with AF with IS and 111 ones without IS were enrolled. The plasma levels of TMAO remarkably increased in IS‐AF patients (8.25 ± 1.58 µM) compared with patients with AF (2.22 ± 0.09 µM, P < 0.01). The receiver operating characteristic analysis revealed that the best cutoff value of TMAO to predict IS in patients with AF was 3.53 µM with 75.0% sensitivity and 92.8% specificity (area under the curve: 0.917, 95% confidence intervals: 0.877‐0.957). Univariate and multivariate logistic regression analysis showed that TMAO was an independent predictor in IS. The level of TMAO was correlated with the CHA2DS2‐VASc score. In conclusion, TMAO was an independent predictor of IS, which could potentially refine stroke stratification in patients with AF.  相似文献   

7.
Diacylglycerol acyltransferase (DGAT) could be a rate limiting step in triglyceride (TG) synthesis as it is the final step in this pathway. As such, between depot differences in DGAT activity could influence regional fat storage. DGAT activity and in vitro rates of direct free fatty acid (FFA) storage were measured in abdominal subcutaneous and omental adipose tissue samples from 12 nonobese (BMI <30 kg/m2) and 23 obese men and women (BMI >30 kg/m2) undergoing elective surgery. DGAT activity was greater in omental than in abdominal subcutaneous adipose tissue from nonobese patients (2.0 ± 0.9 vs. 0.9 ± 0.3 pmol/min/mg lipid, respectively, P = 0.003), but not from obese patients (1.4 ± 0.6 vs. 1.7 ± 0.7 pmol/min/mg lipid, respectively, P = 0.10). DGAT activity per unit adipose weight was negatively correlated with adipocyte size (P < 0.01) and positively correlated with direct FFA storage in omental (P < 0.001) but not in abdominal subcutaneous fat. Tissue DGAT activity varies as a function of adipocyte size, but this relationship differs between visceral and abdominal subcutaneous fat in obese and nonobese humans. Our results are consistent with the hypothesis that interindividual variations in DGAT activity may be an important regulatory step in visceral adipose tissue FFA uptake/storage.  相似文献   

8.
We investigated global and regional effects of myocardial transplantation of human induced pluripotent stem cell (iPSC)‐derived mesenchymal stem cells (iMSCs) in infarcted myocardium. Acute myocardial infarction (MI) was induced by ligation of left coronary artery of severe combined immunodeficient mice before 2 × 105 iMSCs or cell‐free saline were injected into peri‐infarcted anterior free wall. Sham‐operated animals received no injection. Global and regional myocardial function was assessed serially at 1‐week and 8‐week by segmental strain analysis by using two dimensional (2D) speckle tracking echocardiography. Early myocardial remodelling was observed at 1‐week and persisted to 8‐week with global contractility of ejection fraction and fractional area change in saline‐ (32.96 ± 14.23%; 21.50 ± 10.07%) and iMSC‐injected (32.95 ± 10.31%; 21.00 ± 7.11%) groups significantly depressed as compared to sham control (51.17 ± 11.69%, P < 0.05; 34.86 ± 9.82%, P < 0.05). However, myocardial dilatation was observed in saline‐injected animals (4.40 ± 0.62 mm, P < 0.05), but not iMSCs (4.29 ± 0.57 mm), when compared to sham control (3.74 ± 0.32 mm). Furthermore, strain analysis showed significant improved basal anterior wall strain (28.86 ± 8.16%, P < 0.05) in the iMSC group, but not saline‐injected (15.81 ± 13.92%), when compared to sham control (22.18 ± 4.13%). This was corroborated by multi‐segments deterioration of radial strain only in saline‐injected (21.50 ± 5.31%, P < 0.05), but not iMSC (25.67 ± 12.53%), when compared to sham control (34.88 ± 5.77%). Improvements of the myocardial strain coincided with the presence of interconnecting telocytes in interstitial space of the infarcted anterior segment of the heart. Our results show that localized injection of iMSCs alleviates ventricular remodelling, sustains global and regional myocardial strain by paracrine‐driven effect on neoangiogenesis and myocardial deformation/compliance via parenchymal and interstitial cell interactions in the infarcted myocardium.  相似文献   

9.

The primary aim of our study was to determine the influence of taking chromium plus carnitine on insulin resistance, with a secondary objective of evaluating the influences on lipid profiles and weight loss in overweight subjects with polycystic ovary syndrome (PCOS). In a 12-week randomized, double-blind, placebo-controlled clinical trial, 54 overweight women were randomly assigned to receive either supplements (200 μg/day chromium picolinate plus 1000 mg/day carnitine) or placebo (27/each group). Chromium and carnitine co-supplementation decreased weight (− 3.6 ± 1.8 vs. − 1.0 ± 0.7 kg, P < 0.001), BMI (− 1.3 ± 0.7 vs. − 0.3 ± 0.3 kg/m2, P < 0.001), fasting plasma glucose (FPG) (− 5.1 ± 6.0 vs. − 1.1 ± 4.9 mg/dL, P = 0.01), insulin (− 2.0 ± 1.4 vs. − 0.2 ± 1.2 μIU/mL, P < 0.001), insulin resistance (− 0.5 ± 0.4 vs. − 0.04 ± 0.3, P < 0.001), triglycerides (− 18.0 ± 25.2 vs. + 5.5 ± 14.4 mg/dL, P < 0.001), total (− 17.0 ± 20.3 vs. + 3.6 ± 12.0 mg/dL, P < 0.001), and LDL cholesterol (− 13.3 ± 19.2 vs. + 1.4 ± 13.3 mg/dL, P = 0.002), and elevated insulin sensitivity (+ 0.007 ± 0.005 vs. + 0.002 ± 0.005, P < 0.001). In addition, co-supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.02) and low-density lipoprotein receptor expression (P = 0.02). Overall, chromium and carnitine co-supplementation for 12 weeks to overweight women with PCOS had beneficial effects on body weight, glycemic control, lipid profiles except HDL cholesterol levels, and gene expression of PPAR-γ and LDLR. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N38.

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10.
This study aims to determine whether a semi-quantitative assessment of inflammatory response in tumor and stroma on routine hematoxylin and eosin-stained (H&E) slides can predict survival in patients with epithelioid malignant pleural mesothelioma (MPM). H&E sections of 175 epithelioid MPM specimens from a single institution (1989–2009) were reviewed. Patients who received neoadjuvant chemotherapy were excluded from analysis. Each tumor was histologically assessed for acute and chronic inflammatory response both within the tumor and the stromal component. Inflammatory response was graded: low (none to mild infiltrate) or high (moderate to severe infiltrate). Log-rank test and Cox proportional hazards regression were used to investigate the association between the degree of inflammation (acute/tumor, acute/stroma, chronic/tumor, and chronic/stroma) and overall survival (OS). Patients with high chronic inflammatory response in stroma (n = 59) had improved survival compared to low (n = 116) (median OS = 19.4 vs. 15.0 months, P = 0.01). This prognostic stratification remained significant in stage III patients (median OS = 16.0 vs. 9.3 months, P = 0.03). In multivariate analysis, chronic inflammation in stroma was an independent predictor of survival (HR = 0.659, 95% CI 0.464–0.937, P = 0.02). While high degree of chronic inflammatory cell infiltration in the stromal component was associated with improved overall survival, degree of other inflammatory responses did not show significant correlation with OS. Our study for the first time investigates inflammatory response in tumor and stroma and not only suggests the prognostic value of inflammatory response in epithelioid MPM but also provides rationale for investigation of immunotherapy to benefit epithelioid MPM patients.  相似文献   

11.
Objectives: Myofibroblasts are a vital component of stroma of many malignant neoplasms, but it is not yet established whether stromal myofibroblasts also exist in benign tumours such as oncocytoma of the kidney. Materials and methods: Histomorphological and immunohistochemical analysis of 16 renal oncocytomas diagnosed at Chang Gung Memorial Hospital, Taiwan, has been performed. Results: Renal oncocytomas were composed of oncocytes, large cells with granular eosinophilic cytoplasm, arranged mostly in sheets, in tubulocystic or combined pattern. Few oncocytes appeared to be undergoing proliferation or apoptosis. MIB‐1 and active caspase 3 indices were low, but higher in tumour than in surrounding non‐tumour parenchyma (MIB‐1: 0.93 ± 0.09 versus 0.46 ± 0.07, P < 0.001 and active caspase 3: 0.76 ± 0.08 versus 0.41 ± 0.09, P < 0.001). Wnt/β‐catenin signalling was not implicated in this neoplasm, as there was no loss of E‐cadherin membranous localization or expression of intranuclear β‐catenin in the cells. Clumps of oncocytes were stained with periodic acid Schiff and had collagen I‐, collagen III‐ and fibronectin‐positive, but desmin‐ and human caldesmon‐negative stromas. Importantly, α‐smooth muscle actin (SMA)‐immunostaining established the myofibroblastic nature of many of the stromal cells. Some of the myofibroblasts were also positive for MIB‐1, indicating a proliferative role for them in the stroma. Conclusions: Renal oncocytomas were composed of two independent compartments: benign oncocytes and pronounced fibrotic stroma, which consisted of proliferating myofibroblasts (SMA‐ and MIB‐1‐positive) which were associated with excessive deposition of extracellular matrix (periodic acid Schiff‐component, collagen I‐, collagen III‐ and fibronectin‐positive, and desmin‐ and human caldesmon‐negative).  相似文献   

12.
Bowal or ferricrete, the final of land degradation, occurred only in tropical region. This study aimed at assessing the effects of bowalization on phytodiversity, life forms and morphological response of plant species using Combretum nigricans Leprieur ex Guill. & Perr. as a case study. Morphological parameters (height, number of stems, number of branches, diameter at breast height and crown diameter) of C. nigricans were determined in the sub‐humid zone of Benin. Plant communities were determined according to Multi‐Response Permutation Procedures analysis. Plant communities were more diversified on sand‐clay and concretion soils (control) compared with those described on bowal. C. nigricans developed more stems (3.6 ± 1.4 stems vs. 1.3 ± 0.4 stems), more branches (5.9 ± 2.4 branches vs. 3.2 ± 0.6 branches) and large crown diameter (5 ± 1.48 m vs. 3.4 ± 1.2 m) on bowal than on sand‐clay soil. The best adapted life forms on bowal were therophytes. Bowalization induced loss of phytodiversity, changes in species life forms and provoked local adaptation of tree species.  相似文献   

13.
The purpose of this study was to mark endangered sterlet (Acipenser ruthenus) with visible implant elastomer (VIE) in order to assess mortality, compatibility, retention, persistence and histological reactions resulting from this tagging technique. It was hypothesized there would be only minor effects on the fishes' health, and assumed that acute effects would be more pronounced than long‐term effects. On 11 September 2013, 20 specimens were tagged ventrally with visible implant elastomer, 20 received a subcutaneous injection with 0.9% NaCl solution, and another 20 served as untreated control. Mean total length was 28.0 ± 1.8 cm and mean body mass 64.1 ± 12.0 g. The sterlets were kept in four 4,000‐L tanks filled with 2,400‐L water. Acute effects were monitored for 95 days, where fish were held at temperatures between 2.4°C and 15.2°C, reflecting outdoor conditions. Chronic effects were examined 282 days post‐tagging through histological sections of the tagging region in five sterlets. During the first 95 days of observation, tag retention was 100%. No signs of incompatibility were detected. Body mass did not significantly differ between VIE‐tagged fish and controls. At day 282 post‐tagging, however, distinct tissue reactions were visible at the tagging sites of nine fish. Histological examination of five fish revealed a variable degree of infiltration with leukocytes in the areas around the elastomer, which did not necessarily correspond with the externally visible degree of inflammation. After medical treatment, the lesions healed without complications, whereas the retention rate of the VIE tags was 5%. According to the findings, the tag location rather than the tag itself was responsible for the externally visible irritations, indicating that the ventral subcutis of sterlet is not a suitable site, even for small VIE tags in long‐term studies. The results of this study also suggest that VIE marking should in general be critically evaluated before application in field studies.  相似文献   

14.
Aging is associated with vascular endothelial dysfunction, reduced exercise tolerance, and impaired whole‐body glucose metabolism. Interleukin‐37 (IL‐37), an anti‐inflammatory cytokine of the interleukin‐1 family, exerts salutary physiological effects in young mice independent of its inflammation‐suppressing properties. Here, we assess the efficacy of IL‐37 treatment for improving physiological function in older age. Old mice (26–28 months) received daily intraperitoneal injections of recombinant human IL‐37 (recIL‐37; 1 µg/200 ml PBS) or vehicle (200 ml PBS) for 10–14 days. Vascular endothelial function (ex vivo carotid artery dilation to increasing doses of acetylcholine, ACh) was enhanced in recIL‐37 vs. vehicle‐treated mice via increased nitric oxide (NO) bioavailability (all p < .05); this effect was accompanied by enhanced ACh‐stimulated NO production and reduced levels of reactive oxygen species in endothelial cells cultured with plasma from IL‐37‐treated animals (p < .05 vs. vehicle plasma). RecIL‐37 treatment increased endurance exercise capacity by 2.4‐fold, which was accompanied by a 2.9‐fold increase in the phosphorylated AMP‐activated kinase (AMPK) to AMPK ratio (i.e., AMPK activation) in quadriceps muscle. RecIL‐37 treatment also improved whole‐body insulin sensitivity and glucose tolerance (p < .05 vs. vehicle). Improvements in physiological function occurred without significant changes in plasma, aortic, and skeletal muscle pro‐inflammatory proteins (under resting conditions), whereas pro‐/anti‐inflammatory IL‐6 was greater in recIL‐37‐treated animals. Plasma metabolomics analysis revealed that recIL‐37 treatment altered metabolites related to pathways involved in NO synthesis (e.g., increased L‐arginine and citrulline/arginine ratio) and fatty acid metabolism (e.g., increased pantothenol and free fatty acids). Our findings provide experimental support for IL‐37 therapy as a novel strategy to improve diverse physiological functions in old age.  相似文献   

15.
Objective: To determine whether racial differences exist in the relationship of the abnormalities defining the metabolic syndrome (MS) to regional adiposity and fat cell size (FCS) in obese postmenopausal women. Research Methods and Procedures: We determined the relationship of metabolic variables associated with the MS to regional body composition and abdominal (ABD) and gluteal (GLT) FCS in 25 white (CAU) and 25 African‐American (AF‐AMER) older women matched for age (58 ± 5 years; mean ± SD) and BMI (35 ± 4 kg/m2). Results: MS was present in 36% of the AF‐AMER and 57% of the CAU women. There were no differences in total body, trunk, gluteofemoral fat mass or regional FCS, but AF‐AMER women had 22% lower visceral fat, 24% higher insulin, and 31% lower triglyceride levels than CAU women (p < 0.05). Multiple regression analysis with body fat, visceral ABD fat area, and FCS as independent variables showed that GLT FCS was independently correlated with 2‐hour insulin (r = 0.56), triglyceride (r = 0.62), and high‐density lipoprotein cholesterol (r = ?0.72) levels in AF‐AMER women but not in CAU women, where only systolic blood pressure correlated with subcutaneous ABD fat area (r = 0.57) (p < 0.05). Discussion: The associations between GLT FCS and metabolic dysfunction in obese AF‐AMER but not CAU women suggest that central obesity is a less valid predictor of the MS in obese postmenopausal AF‐AMER women than in CAU women and that GLT FCS may be a more sensitive indicator of risk for the MS in AF‐AMER women.  相似文献   

16.
Standard microelectrode technique was used to study electrical activity of the isolated heart of the polychaete annelid, Arenicola marina. Typical pacemaker activity with slow diastolic depolarization was observed in all recordings. The average maximum diastolic potential (−58.4 ± 3.2 mV), the average amplitude of the action potential (28.7 ± 4.7 mV) and the average total duration of the action potential (2,434 ± 430 ms) were determined. There has been no gradient of automaticity observed in our studies, which suggests that all regions of the Arenicola heart could possess pacemaker functions. Acetylcholine (ACh) produced a concentration dependent (5 × 10−8–5 × 10−5 M) increase of the beating rate via increase in the rate of the diastolic depolarization. ACh (5 × 10−5 M) increased beating rate by 2.5-fold compared to the control rate. A stronger action of ACh resulted in depolarization, block of action potential generation and contracture of the heart. The non-hydrolysable ACh analog carbacholine (10−8–10−6 M) produced similar effects. All effects of ACh and carbacholine were abolished by 5 × 10−6 M atropine. d-Tubocurarine (5 × 10−5 M) did not significantly alter effects of ACh or carbacholine. Epinephrine (10−8–10−6 M) caused the slowing of pacemaker activity and marked decrease of action potential duration. 10−6 M epinephrine produced complete cardiac arrest. The effects of epinephrine were not significantly altered by the β-blocker propranolol (5 × 10−6 M). The β-agonist isoproterenol (10−7–10−5 M) and the α-agonist xylometazoline (10−6–10−5 M) did not produce significant effects. Thus, cholinergic effects in the Arenicola heart are likely to be mediated via muscarinic receptors, while the nature of adrenergic effects needs further investigation.  相似文献   

17.

To the best of our knowledge, this study is the first evaluating the effects of probiotic honey intake on glycemic control, lipid profiles, biomarkers of inflammation, and oxidative stress in patients with diabetic nephropathy (DN). This investigation was conducted to evaluate the effects of probiotic honey intake on metabolic status in patients with DN. This randomized, double-blind, controlled clinical trial was performed among 60 patients with DN. Patients were randomly allocated into two groups to receive either 25 g/day probiotic honey containing a viable and heat-resistant probiotic Bacillus coagulans T11 (IBRC-M10791) (108 CFU/g) or 25 g/day control honey (n = 30 each group) for 12 weeks. Fasting blood samples were taken at baseline and 12 weeks after supplementation to quantify glycemic status, lipid concentrations, biomarkers of inflammation, and oxidative stress. After 12 weeks of intervention, patients who received probiotic honey compared with the control honey had significantly decreased serum insulin levels (− 1.2 ± 1.8 vs. − 0.1 ± 1.3 μIU/mL, P = 0.004) and homeostasis model of assessment-estimated insulin resistance (− 0.5 ± 0.6 vs. 0.003 ± 0.4, P = 0.002) and significantly improved quantitative insulin sensitivity check index (+ 0.005 ± 0.009 vs. − 0.0007 ± 0.005, P = 0.004). Additionally, compared with the control honey, probiotic honey intake has resulted in a significant reduction in total-/HDL-cholesterol (− 0.2 ± 0.5 vs. + 0.1 ± 0.1, P = 0.04). Probiotic honey intake significantly reduced serum high-sensitivity C-reactive protein (hs-CRP) (− 1.9 ± 2.4 vs. − 0.2 ± 2.7 mg/L, P = 0.01) and plasma malondialdehyde (MDA) levels (− 0.1 ± 0.6 vs. + 0.6 ± 1.0 μmol/L, P = 0.002) compared with the control honey. Probiotic honey intake had no significant effects on other metabolic profiles compared with the control honey. Overall, findings from the current study demonstrated that probiotic honey consumption for 12 weeks among DN patients had beneficial effects on insulin metabolism, total-/HDL-cholesterol, serum hs-CRP, and plasma MDA levels, but did not affect other metabolic profiles. http://www.irct.ir: IRCT201705035623N115.

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18.
Climate change alters the abiotic constraints faced by plants, including increasing temperature and water stress. These changes may affect flower development and production of flower rewards, thus altering plant–pollinator interactions. Here, we investigated the consequences of increased temperature and water stress on plant growth, floral biology, flower‐reward production, and insect visitation of a widespread bee‐visited species, Borago officinalis. Plants were grown for 5 weeks under three temperature regimes (21, 24, and 27°C) and two watering regimes (well‐watered and water‐stressed). Plant growth was more affected by temperature rise than water stress, and the reproductive growth was affected by both stresses. Vegetative traits were stimulated at 24°C, but impaired at 27°C. Flower development was mainly affected by water stress, which decreased flower number (15 ± 2 flowers/plant in well‐watered plants vs. 8 ± 1 flowers/plant under water stress). Flowers had a reduced corolla surface under temperature rise and water stress (3.8 ± 0.5 cm2 in well‐watered plants at 21°C vs. 2.2 ± 0.1 cm2 in water‐stressed plants at 27°C). Both constraints reduced flower‐reward production. Nectar sugar content decreased from 3.9 ± 0.3 mg/flower in the well‐watered plants at 21°C to 1.3 ± 0.4 mg/flower in the water‐stressed plants at 27°C. Total pollen quantity was not affected, but pollen viability decreased from 79 ± 4% in the well‐watered plants at 21°C to 25 ± 9% in the water‐stressed plants at 27°C. Flowers in the well‐watered plants at 21°C received at least twice as many bumblebee visits compared with the other treatments. In conclusion, floral modifications induced by abiotic stresses related to climate change affect insect behavior and alter plant–pollinator interactions.  相似文献   

19.
Initial microsatellite studies suggested that muskoxen display the lowest microsatellite polymorphism in a large ungulate. We optimized 17 di‐nucleotide microsatellites with longer repeats from a muskox DNA library and surveyed 18 animals from across their natural range. Loci with perfect repeats were more variable than imperfect loci: Hperfect = 0.504 ± 0.045 (± SE) vs. Himperfect = 0.067 ± 0.055. Our Hperfect estimate is higher than previous low estimates of HE = 0.018 and HE = 0.059.  相似文献   

20.
  • Acetylcholine (ACh) is believed to improve plant growth. However, regulation at biochemical and molecular levels is largely unknown.
  • The present study investigated the impact of exogenously applied ACh (10 µm ) on growth and chlorophyll metabolism in hydroponically grown Nicotiana benthamiana under salt stress (150 mm NaCl).
  • Salinity reduced root hydraulic conductivity while ACh‐treated seedlings exhibited a significant increase, resulting in increased relative water content. Salinity induced a reduction in chlorophyll biosynthetic intermediates, such as protoporphyrin‐IX, Mg‐photoporphyrin‐IX and protochlorophyllide, which were significantly ameliorated in the presence of ACh. This influence of ACh on chlorophyll synthesis was confirmed by up‐regulation of HEMA1, CHLH, CAO and POR genes. Gas exchange parameters, i.e. stomatal conductance, internal CO2 concentration and transpiration rate, increased with ACh, thereby alleviating the salinity effects on photosynthesis. In addition, the salinity‐induced enhancement of lipid peroxidation declined after ACh treatment through modulation of the activity of the assayed antioxidant enzymes (superoxide dismutase and peroxidase). Importantly, ACh significantly reduced the uptake of Na and increased uptake of K, resulting in a decline in the Na/K ratio.
  • Results of the present study indicate that ACh can be effective in ameliorating NaCl‐induced osmotic stress, altering chlorophyll metabolism and thus photosynthesis by maintaining ion homeostasis, hydraulic conductivity and water balance.
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