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61.
The grey level of co‐occurrence matrix (GLCM) is a texture analysis approach accounting for spatial distribution of the pixels from an image and can be a promising method for exercise‐induced muscle damage (EIMD) studies. We followed up the time changes of two GLCM texture parameters and echo intensity (EI) on ultrasound images after eccentric contractions. Thirteen untrained women performed two sets of ten elbow flexions eccentric contractions. Ultrasound images were acquired at baseline and 24 h, 48 h, 72 h and 96 h after exercise. Two GLCM texture parameters were calculated for the brachialis muscle: contrast (CON) and correlation (COR). Peak torque, EI, muscle thickness (MT) and soreness were measured. The peak torque and soreness decreased immediately after the intervention in comparison with all the measures. MT increased immediately after the intervention remaining for 72 h (P<0·05). Significant increases (P<0·05) were observed for COR (48, 72 and 96 h) and EI only at 72 and 96 h. The increasing COR represents high similarity between grey levels, which could be observed on US images after few days on eccentric training for elbow flexors.  相似文献   
62.
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.  相似文献   
63.

Background and Purpose

The urinary bladder urothelium expresses various receptors and in response to chemical and mechanical stimuli releases mediators, thereby modulating bladder sensory pathways. Transient receptor potential vanilloid 1 (TRPV1) ion channels and nerve growth factor (NGF) in those cells are implicated in this modulatory effect and play a role in sensitizing pain-related afferent pathways during inflammation. In this study, we investigated the interaction between NGF and TRPV1 channels in urothelial cells.

Experimental Approach

Urothelial cells from female Sprague-Dawley rat bladders were cultured to quantify membrane expression of TRPV1 channels and capsaicin-induced ATP release in the presence of NGF alone or with TrKA or PI3K inhibitors. Pain scores from rats with cyclophosphamide (CYP)-induced bladder inflammation were assessed after treatment with a TrkA antagonist. Bladders (from control and CYP rats) were collected and analysed for NGF content and TRPV1 channel expression.

Key Results

Cultured cells responded to NGF with increased TRPV1 channel expression in the cell membrane and increased release of ATP. Both responses were blocked by either a TrkA antagonist or a PI3K inhibitor. Treatment in vivo with the TrkA antagonist alleviated pain symptoms and reduced CYP-induced NGF overexpression in the mucosa. Furthermore, in urothelial cells from animals with bladder inflammation, expression of TRPV1 channels in the membrane was significantly increased.

Conclusions and Implications

During bladder inflammation, increased production of NGF in urothelial cells induced increased expression and activity of TRPV1 channels in the cell membrane. This effect was primarily mediated by the PI3K pathway.  相似文献   
64.
IntroductionThis study aimed to evaluate the performance of non-vitamin K antagonist oral anticoagulation (NOAC) in patients with previous stroke and non-valvular atrial fibrillation (AF) compared with left atrial appendage occlusion (LAAO) in primary and secondary stroke prevention settings.MethodsThis was a prospective, single-center, non-randomized cohort study of 302 consecutive patients with non-valvular AF and at high risk for stroke. Two treatment strategies were compared: LAAO (n=91) and long-term treatment with NOAC (n=149). The primary outcome was the composite endpoint of death, stroke and major bleeding. Propensity score and cause-of-death analyses were performed to compare outcomes.ResultsIn a mean follow-up of 13 months, there were 30 deaths (LAAO 8.8% vs. NOAC 14.8%), five strokes (LAAO 1.1% vs. NOAC 2.7%) and six major bleeds (LAAO 1.1% vs. NOAC 3.4%). There was a non-significant trend for a lower incidence of the primary endpoint in the LAAO group (11.0% vs. 20.9%; HR 0.42, 95% CI 0.17-1.05, p=0.064). Considering only secondary prevention LAAO patients (34.1% of the LAAO group), there was also a non-significant lower incidence of the primary endpoint (LAAO 6.5% vs. 20.9%; HR 0.30, 95% CI 0.07-1.39, p=0.12). While about a fifth of LAAO patients stopped antiplatelet treatment six months after device implantation due to recurrent minor bleeding, no adverse cardiovascular event or major bleeding occurred in this subset of patients.ConclusionIn this registry-based study, LAAO was a reasonable alternative to NOAC for the prevention of a composite endpoint of all-cause mortality, stroke and major bleeding in patients at high risk for stroke.  相似文献   
65.
BACKGROUND: The main process involved in hepatic osteodystrophy seems to be osteoporosis, but decreased 25-hydroxylation of vitamin D might lead to osteomalacia and secondary hyperparathyroidism. METHODS AND RESULTS: We studied bone mineral density (BMD) by using DEXA-Expert Lunar, biochemical markers of bone turnover and calcium-parathyroid hormone (PTH)-vitamin D axis in 100 patients with chronic viral hepatitis secondary to hepatitis C virus: 49 non-cirrhotic (NCir) and 51 with cirrhosis (Cir) confirmed by liver biopsy and/or clinical and biochemical features. When compared to the age-matched population, 25% of the patients had low BMD at the lumbar spine (LS), 26.2% at Ward's triangle, 15.5% at the femoral neck (FN), and 20.2% at the trochanter. No difference was found either between Cir and NCir groups or between sexes. Urinary N-telopeptide was increased in 31.86% of the patients, and negatively correlated with BMD at the LS and trochanter (P < 0.02). Serum bone-specific alkaline phosphatase was elevated in 21% of the patients and negatively correlated with BMD at the trochanter and Ward's triangle (P < 0.02). Fasting 25-hydroxyvitamin D was low in only three Cir patients, with no difference between the Cir and NCir groups, but it was higher in men (51.8 +/- 16.0 ng/mL) compared to women (40.4 +/- 14.4 ng/mL; P = 0.001). Fasting serum calcium was lower in Cir than NCir patients, P = 0.019. Fasting intact PTH was elevated in 42% of the patients, but the mean serum levels were similar in Cir and NCir groups. CONCLUSION: We found no evidence of vitamin D deficiency, but cannot exclude the participation of PTH in the high bone turnover and bone loss in the population with chronic viral hepatitis.  相似文献   
66.
Limiting dysfunctional neutrophilic inflammation while preserving effective immunity requires a better understanding of the processes that dictate neutrophil function in the tissues. Quantitative mass-spectrometry identified how inflammatory murine neutrophils regulated expression of cell surface receptors, signal transduction networks, and metabolic machinery to shape neutrophil phenotypes in response to hypoxia. Through the tracing of labeled amino acids into metabolic enzymes, proinflammatory mediators, and granule proteins, we demonstrated that ongoing protein synthesis shapes the neutrophil proteome. To maintain energy supplies in the tissues, neutrophils consumed extracellular proteins to fuel central carbon metabolism. The physiological stresses of hypoxia and hypoglycemia, characteristic of inflamed tissues, promoted this extracellular protein scavenging with activation of the lysosomal compartment, further driving exploitation of the protein-rich inflammatory milieu. This study provides a comprehensive map of neutrophil proteomes, analysis of which has led to the identification of active catabolic and anabolic pathways that enable neutrophils to sustain synthetic and effector functions in the tissues.  相似文献   
67.
PURPOSETo assess the effects of three-dimensional image-guided brachytherapy (3D BT) compared to bi-dimensional BT (2D BT) on clinical outcomes in patients with cervical cancer.METHODS AND MATERIALSWe searched PubMed/MEDLINE, EMBASE, Scopus, CENTRAL, Web of Science, and LILACS for studies assessing the effects of 3D BT versus 2D BT on clinical outcomes. Two reviewers independently screened retrieved citations, extracted data and assessed risk of bias from eligible studies. Hazard ratios (HR) were calculated from Kaplan-Meier curves considering the number of events, their timing and the followup of censored patients. We conducted meta-analyses of HR using the inverse-variance random-effects method. Risk Difference (RD) for toxicities were pooled using the Mantel–Haenszel random-effects method. We used the GRADE system to rate the certainty of evidence.RESULTSTwenty observational studies involving 4287 patients were included. The meta-analyses assessing the effect of 3D BT versus 2D BT on overall survival resulted in a HR of 0.78 (95%CI 0.62–0.98), HR of 0.75 (95%CI 0.62–0.90) for pelvic disease-free survival, HR of 0.93 (95%CI 0.81–1.06) for metastatic disease-free survival, and HR of 0.77 (95%CI 0.59–0.99) for local control. Grade 3–4 global and gastrointestinal toxicities were, respectively, 9% lower (95%CI 6% to 11%) and 5% lower (95%CI 2% to 8%) in patients receiving 3D BT versus 2D BT. Certainty of evidence was very low for all assessed outcomes.CONCLUSIONSOur study may suggest a benefit of 3D BT over conventional 2D BT on important clinical outcomes.  相似文献   
68.
Abstract

In some clinical situations, the clinician may encounter previously installed implants that should be associated with other implants for a proper rehabilitation. The aim of this study was to evaluate the biomechanical behaviour of a multiple prosthesis joined by different implant connections using photoelasticity. Photoelastic models with a screwed fixed prosthesis supported by implants with different connection systems (Morse taper, external hexagon, internal hexagon, and Flexcone), and different combinations among them, were fabricated. Each assembly was placed in a circular polariscope, and axial and oblique (45°) loads of 100 N were applied on the occlusal surface of the crowns. The fringe patterns were photographed and the analysis was performed by counting the number of high-intensity fringes and also according to the stress distribution region where they appeared. Among implants of the same connection, the external connections obtained a greater number of high intensity fringes when compared to the internal connections. From the biomechanical point of view, the association between different types of connections obtained positive results.  相似文献   
69.
Apoptosis regulation in luteinized granulosa cells (LGC) during assisted reproduction procedures is still controversial. Caspase-3 is a major apoptosis mediator encoded by CASP3 and formed through cleavage of its precursor pro-caspase-3. The aim of this study was to investigate the expression patterns of pro-caspase-3 (mRNA and protein) and cleaved caspase-3 in human LGC. Thirty-five women undergoing controlled ovarian stimulation for in vitro fertilization were prospectively enrolled in the study. LGC were isolated from follicular fluid during oocyte pickup and evaluated by immunocytochemistry for pro-caspase-3 and cleaved caspase-3, and by real-time PCR for CASP3 mRNA expression. We found a positive staining of pro-caspase-3 in 77 % of the LGC (95 % confidence interval [CI] 60%–84%), whereas cleaved caspase-3 was found in only 4% of the cells (95 % CI 3%–6%). The abundance of cells expressing pro-caspase-3 was independent from CASP3 mRNA levels (r = 0.24, p = 0.255) and did not correlate with the amount of cleaved caspase-3 (r = -0.24, p = 0.186). Multivariable logistic regression showed that pro-caspase-3 positivity was not influenced by clinical characteristics such as age, cause or length of infertility, antral follicle count or hormonal drugs used to induce ovulation. These findings suggest that pro-caspase-3 is constitutively expressed in LGC, allowing quick cleavage into active caspase-3 and apoptosis triggering whenever needed in the course of gonadotropin-induced follicular development.  相似文献   
70.
Ketamine (KET) is an N-methyl-D-aspartate (NMDA) antagonist with rapid and long-lasting antidepressant effects, but how the drug shows its sustained effects is still a matter of controversy. The objectives were to evaluate the mechanisms for KET rapid (30 min) and long-lasting (15 and 30 days after) antidepressant effects in mice. A single dose of KET (2, 5, or 10 mg/kg, po) was administered to male Swiss mice and the forced swim test (FST) was performed 30 min, 15, or 30 days later. Imipramine (IMI, 30 mg/kg, ip), a tricyclic antidepressant drug, was used as reference. The mice were euthanized, separated into two time-point groups (D1, first day after KET injection; D30, 30 days later), and brain sections were processed for glycogen synthase kinase-3 (GSK-3), histone deacetylase (HDAC), brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP) immunohistochemical assays. KET (5 and 10 mg/kg) presented rapid and long-lasting antidepressant-like effects. As expected, the immunoreactivities for brain GSK-3 and HDAC decreased compared to control groups in all areas (striatum, DG, CA1, CA3, and mainly pre-frontal cortex, PFC) after KET injection. Increases in BDNF immunostaining were demonstrated in the PFC, DG, CA1, and CA3 areas at D1 and D30 time-points. GFAP immunoreactivity was also increased in the PFC and striatum at both time-points. In conclusion, KET changed brain BDNF and GFAP expressions 30 days after a single administration. Although neuroplasticity could be involved in the observed effects of KET, more studies are needed to explain the mechanisms for the drug’s sustained antidepressant-like effects.  相似文献   
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