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81.
Cardiac hypertrophy is a major risk factor for many serious heart diseases. Recent data demonstrated the role of cytochrome P450 (CYP)-derived arachidonic acid (AA) metabolites in cardiovascular pathophysiology. In the current study our aim was to determine the aberrations in CYP-mediated AA metabolism in the heart during cardiac hypertrophy. Pressure overload cardiac hypertrophy was induced in Sprague Dawley rats using the descending aortic constriction procedure. Five weeks post-surgery, the cardiac levels of AA metabolites were determined in hypertrophied and normal hearts. In addition, the formation rate of AA metabolites, as well as, CYP expression in cardiac microsomal fraction was also determined. AA metabolites were measured by liquid chromatography–electrospray ionization-mass spectroscopy, whereas, the expression of CYPs was determined by Western blot analysis. Non-parametric analysis was performed to examine the association between metabolites formation and CYP expressions. Our results showed that 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids (EETs), and 5-, 12-, 15-, and 20-hydroxyeicosatetraenoic acids (HETEs) levels were increased, whereas, 19-HETE formation was decreased in hypertrophied hearts. The increase in EETs was linked to CYP2B2. On the other hand, CYP1B1 and CYP2J3 were involved in mid-chain HETE metabolism, whereas, CYP4A2/3 inhibition was involved in the decrease in 19-HETE formation in hypertrophied hearts. In conclusion, CYP1B1 played cardiotoxic role, whereas, CYP2B2, CYP2J3 and CYP4A2/3 played cardioprotective roles during pressure overload-induced cardiac hypertrophy. These CYP can be valid targets for the development of drugs to treat and prevent cardiac hypertrophy and heart failure.  相似文献   
82.
Tricuspid valve disease carries a very unfavorable prognosis when medically treated. Despite that, surgical intervention is still underperformed for tricuspid valve disease due to the reported high morbidity and mortality from a sternotomy approach. This had led to a shift towards maximizing medical therapy for right ventricular failure and, as a result, a more significant delay in surgical referrals with surgical risks when patients are finally referred. Tricuspid valve patients usually have other co-morbidities resulting from their systemic venous congestion and low flow cardiac output. Minimally invasive tricuspid valve surgery provides less tissue injury and, as a result, less trauma during surgery. This provides a hope for both patients and treating doctors to be more open for providing this procedure with less complications. Isolated minimally invasive tricuspid valve surgery is still not performed as widely as expected. This can be partly due to the adverse outcomes historically labelled to tricuspid valve surgery or by the long journey of learning the surgical team would need to commit to with a minimal access approach. In this article we will review the perioperative pathway, and outcomes of isolated minimally invasive tricuspid valve surgery in the available English literature.  相似文献   
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As a synthetic analogue of adrenocorticotropic hormone (ACTH), tetracosactide is prohibited in sport by the World Anti‐Doping Agency (WADA). An enzyme‐linked immunosorbent assay (ELISA) method is proposed for detection of this drug in plasma. Since its structure corresponds to the 24 N‐terminal of the 39 amino acids of the natural endogenous peptide ACTH, tetracosactide can be detected with a commercial ELISA kit for ACTH that uses antibodies, the epitopes of which are located in the 1?24 part of ACTH. However, an essential condition for detection specificity is the preliminary total clearance of endogenous ACTH in the plasma samples. This is achieved by a preparative step based on cation‐exchange chromatography before ELISA. The method is specific and sensitive (LOD: 30 pg/mL) and may be used as a screening analysis in anti‐doping control. The pre‐analytical conditions are shown to be of the upmost importance and recommendations for blood collection (EDTA tubes), sample transport (4 °C) and plasma sample storage (‐20 °C) are presented. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
86.
Background: Fungi growing on wood cause deterioration of stored food materials or discoloration of the wood itself, and the search for new and safe bioagents is recently needed. Methods: Essential oils (EOs) from aerial parts from Mentha longifolia L. and Citrus reticulata L., analyzed by gas chromatography-mass spectrometry (GC-MS), were tested for their antifungal activity by the vapor method against four common fungi, Aspergillus flavus, A. niger, A. fumigatus, and Fusarium culmorum, and confirmed by SEM examination as the oils applied on wood samples. Results: The most abundant compounds identified in the EO from M. longifolia were menthone and eucalyptol; in C. reticulata EO, they were β-caryophyllene, β-caryophyllene oxide, and β-elemene. EOs from M. longifolia and C. reticulata, at 500 and 250 µL/mL, showed potent antifungal activity against A. flavus and A. fumigatus, with 100% fungal mycelial inhibition growth (FMIG). C. reticulata and M. longifolia EOs, at 125 µL/mL, observed FMIG values of 98% and 95%, respectively, against A. fumigatus. M. longifolia EO, at 500 and 250 µL/mL, showed potent activity against A. niger, with 100% FMIG. F. culmorum completely inhibited (100% FMIG) EOs from M. longifolia and C. reticulata applied at 500 µL/mL. Pinus roxburghii Sarg. Wood, treated with M. longifolia at 125 µL/mL, showed inhibition zone values of 7.33 and 21.33 mm against A. flavus and A. niger, respectively. Conclusions: Both oils possessed good wood-biofungicide activity with the vapor method, as clearly shown by the SEM examination. These activities suggest their possible use as natural wood preservatives.  相似文献   
87.
BackgroundSocio-demographics and comorbidities are involved in determining the severity and fatality in patients with COVID-19 suggested by studies in various countries, but study in Bangladesh is insufficient.AimsWe designed the study to evaluate the association of sociodemographic and comorbidities with the prognosis of adverse health outcomes in patients with COVID-19 in Bangladesh.MethodsA multivariate retrospective cohort study was conducted on data from 966 RT-PCR positive patients from eight divisions during December 13, 2020, to February 13, 2021. Variables included sociodemographic, comorbidities, symptoms, Charlson comorbidity index (CCI) and access to health facilities. Major outcome was fatality. Secondary outcomes included hospitalization, duration of hospital stay, requirement of mechanical ventilation and severity.ResultsMale (65.8%, 636 of 966) was predominant and mean age was 39.8 ± 12.6 years. Fever (79%), dry cough (55%), and loss of test/smell (51%) were frequent and 74% patients had >3 symptoms. Fatality was recorded in 10.5% patients. Comorbidities were found in 44% patients. Hypertension (21.5%) diabetes (14.6%), and cardiovascular diseases (11.3%) were most prevalent. Age >60 years (OR: 4.83, 95% CI: 2.45–6.49), and CCI >3 (OR: 5.48, 95% CI: 3.95–7.24) were predictors of hospitalizations. CCI >4 (aOR: 3.41, 95% CI: 2.57–6.09) was predictor of severity. Age >60 years (aOR: 3.77, 95% CI: 1.07–6.34), >3 symptoms (aOR: 2.14, 95% CI: 0.97–4.91) and CCI >3 vs. CCI <3 (aOR: 5.23, 95% CI: 3.77–8.09) were independently associated with fatality.ConclusionsIncreased age, >3 symptoms, increasing comorbidities, higher CCI were associated with increased hospitalization, severity and fatality in patients with COVID-19.  相似文献   
88.
Background and aimsTo determine the efficacy of i-Port Advance system on patients satisfaction and glycemic control among patients with type 1 diabetes (T1D).MethodsThis prospective study was performed among 73 patients with T1D (13–29 years) at Prince Sultan Military Medical City, Riyadh, Saudi Arabia. Demographic data were collected at baseline and clinical characteristics were collected at baseline and 12 weeks. Patients’ responses to Morisky Medication Adherence Scale (MMAS-8) and Insulin Delivery Satisfaction Survey (IDSS) were recorded at baseline and 12 weeks after initiating the i-Port Advance system.ResultsAt 12 weeks, significant improvement was evident in the IDSS subscales, which comprises the IDSS effective (p = 0.048), burdensome (p = 0.032), and IDSS inconvenient (p = 0.001), with the total baseline IDSS score being 2.6 ± 0.42, and at 12 weeks being 3.7 ± 0.72 (p = 0.037). The MMAS total score at baseline was 4.6 ± 1.2, and at 12 weeks, it increased to 6.4 (p = 0.028). HbA1c level was 8.4% at baseline and decreased to 7.9% (p = 0.001) at 12 weeks. The total daily dose of insulin at baseline registered 0.9 ± 0.13, which declined to 0.8 ± 0.12 (p = 0.048) at 12 weeks. Fasting blood sugar value was 197 ± 23.4 at baseline, which dropped to 182 ± 24.5 at 12 weeks (p = 0.01); and the postprandial glucose at baseline was 195 ± 21.4 and declined to 177 ± 19.2 at 12 weeks (p = 0.01). The hypoglycemic episodes revealed a noteworthy reduction after the i-Port Advance system usage.ConclusionUse of i-Port Advance system was found to raise the patients’ satisfaction levels and lower both the hypoglycemic episodes as well as the HbA1c levels.  相似文献   
89.
AIMS: Despite technical advances in tools used to facilitate implantation of cardiac resynchronization therapy (CRT) devices, there are many hurdles related mainly to the variation in the anatomy of the coronary veins. One such difficulty is the presence of a very proximal origin of the lateral or postero-lateral cardiac vein. METHODS AND RESULTS: We describe an alteration of existing left ventricular (LV) lead delivery sheath with the creation of a side-hole 35-50 mm from its tip. This modification is made to provide access to proximal cardiac vein ostia, while maintaining adequate support for the delivery system. The modified introducer sheath was used in the implantation of six CRT systems (four defibrillators and two pacemakers) in patients who had a proximal origin of the lateral or postero-lateral cardiac vein, all of which were successful and without complications. CONCLUSION: In those patients with unusual proximal origin of target LV veins, modifications of the introducer sheath with the creation of a side-hole facilitate the successful implantation of the LV pacing lead. Until this modified sheath is tested, this technique is considered experimental and may carry unknown risks.  相似文献   
90.
Background: Pancreaticoduodenectomy(PD) is the standard curative treatment for periampullary tumors. The aim of this study is to report the incidence and predictors of long-term survival( ≥ 5 years) after PD. Methods: This study included patients who underwent PD for pathologically proven periampullary adenocarcinomas. Patients were divided into 2 groups: group(I) patients who survived less than 5 years and group(II) patients who survived ≥ 5 years. Results: There were 47(20.6%) long-term survivors( ≥ 5 years) among 228 patients underwent PD for periampullary adenocarcinoma. Patients with ampullary adenocarcinoma represented 31(66.0%) of the long-term survivors. Primary analysis showed that favourable factors for long-term survival include age 60 years old, serum CEA 5 ng/mL, serum CA 19-9 37 U/mL, non-cirrhotic liver, tumor size 2 cm, site of primary tumor, postoperative pancreatic fistula, R0 resection, postoperative chemotherapy, and no recurrence. Multivariate analysis demonstrated that CA 19-9 37 U/mL [OR(95% CI) = 1.712(1.24 8–2.34 8), P = 0.001], smaller tumor size [OR(95% CI) = 1.335(1.032–1.726), P = 0.028] and R0 resection [OR(95% CI) = 3.098(2.095–4.582), P 0.001] were independent factors for survival ≥ 5 years. The prognosis was best for ampullary adenocarcinoma, for which the median survival was 54 months and 5-year survival rate was 39.0%, and the poorest was pancreatic head adenocarcinoma, for which the median survival was 27 months and 5-year survival rate was 7%. Conclusions: The majority of long-term survivors after PD for periampullary adenocarcinoma are patients with ampullary tumor. CA 19-9 37 U/mL, smaller tumor size, and R0 resection were found to be independent factors for long-term survival ≥ 5 years.  相似文献   
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