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51.
52.
The Fourth Universal Definition of Myocardial Infarction (FUDMI) focuses on the distinction between nonischemic myocardial injury and myocardial infarction (MI), along with the role of cardiovascular magnetic resonance, in order to define the etiology of myocardial injury. As a consequence, there is less emphasis on updating the parts of the definition concerning the electrocardiographic (ECG) changes related to MI. Evidence of myocardial ischemia is a prerequisite for the diagnosis of MI, and the ECG is the main available tool for (a) detecting acute ischemia, (b) triage, and (c) risk stratification upon presentation. This review focuses on multiple aspects of ECG interpretation that we firmly believe should be considered for incorporation in any future update to the Universal Definition of MI.  相似文献   
53.
Development and neoplastic progression strongly rely on tumor microenvironment cells. Various kinds of cells that form such tumor milieu play substantial roles in angiogenesis and immunosuppression. Attempts to inhibit tumor vascularization alter tumor milieu and enhance immune response against the tumor. Anticancer therapeutic strategy bringing together antiangiogenic and immunostimulating agents has emerged as a promising approach. We here investigated whether therapy directed against preexisting vessels, combined with an immunomodulatory factor would be equally effective in arresting tumor growth. To this goal, we investigated the effectiveness of ABRaA-vascular endothelial growth factor isoform 121 (VEGF121), an antivascular drug constructed by us. It is a fusion protein composed of VEGF121, and abrin A chain (translation-inhibiting toxin). We used it in combination with interleukin (IL-12) gene therapy and tried to inhibit B16-F10 melanoma tumor growth. ABRaA-VEGF121 is a chimeric recombinant protein capable of destroying tumor vasculature and triggering necrosis in the vicinity of damaged vessels. IL-12 cytokine, in turn, activates both specific and non-specific immune responses. Our results demonstrate that combination of ABRaA-VEGF121 antivascular agent with immunostimulatory cytokine IL-12 indeed inhibits tumor growth more effectively than either agent alone, leading to complete cure of ca. 20 % mice. Post-therapeutic analysis of tumors excised from mice treated with combination therapy showed decreased numbers of blood microvessels in the tumor microenvironment, lowered numbers of regulatory T lymphocytes, as well as showed higher levels of CD4+ and CD8+ as compared to control mice. It seems that bringing together antivascular strategy and the action of immunostimulating agents indeed inhibits growth of tumors.  相似文献   
54.
Under normal conditions, autophagy maintains cardiomyocyte health and integrity through turnover of organelles. During stress, oxygen and nutrient deprivation, or microbial infection, autophagy prolongs cardiomyocyte survival. Sex differences in induction of cell death may to some extent explain the disparity between the sexes in many human diseases. However, sex differences in gene expression, which regulate cell death and autophagy, were so far not taken in consideration to explain the sex bias of viral myocarditis. Coxsackievirus B3 (CVB3)-induced myocarditis is a sex-biased disease, with females being substantially less susceptible than males and sex hormones largely determine this bias. CVB3 was shown to induce and subvert the autophagosome for its optimal viral RNA replication. Gene expression analysis on mouse and human, healthy and CVB3-infected, cardiac samples of both sexes, suggests sex differences in autophagy-related gene expression. This review discusses the aspects of sex bias in autophagy induction in cardiomyocytes.  相似文献   
55.
The adverse metabolic effects of prescribed and endogenous glucocorticoid (GC) excess, Cushing syndrome, create a significant health burden. We found that tissue regeneration of GCs by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), rather than circulating delivery, is critical to developing the phenotype of GC excess; 11β-HSD1 KO mice with circulating GC excess are protected from the glucose intolerance, hyperinsulinemia, hepatic steatosis, adiposity, hypertension, myopathy, and dermal atrophy of Cushing syndrome. Whereas liver-specific 11β-HSD1 KO mice developed a full Cushingoid phenotype, adipose-specific 11β-HSD1 KO mice were protected from hepatic steatosis and circulating fatty acid excess. These data challenge our current view of GC action, demonstrating 11β-HSD1, particularly in adipose tissue, is key to the development of the adverse metabolic profile associated with circulating GC excess, offering 11β-HSD1 inhibition as a previously unidentified approach to treat Cushing syndrome.Estimates suggest that 1–2% of the population of the United States and United Kingdom take prescribed glucocorticoids (GCs) for the treatment of a broad spectrum of inflammatory and autoimmune diseases (1, 2). Despite the efficacy of GCs, 70% of patients experience an adverse systemic side-effect profile. The resultant Cushingoid features include central obesity, proximal myoatrophy, hypertension, skin thinning, osteoporosis, hepatic steatosis, insulin resistance, and type 2 diabetes (3, 4). Collectively, this contributes to increased risk of cardiovascular morbidity and mortality (5, 6). These features are replicated in patients with much rarer endogenous GC excess (Cushing syndrome), as first described by Harvey Cushing in 1932 (7). Current medical therapeutic options that reverse the tissue-specific consequences of hypercortisolism are limited.GC availability and action depend not only upon circulating levels but also on tissue-specific intracellular metabolism by 11β-hydroxysteroid dehydrogenases (11β-HSDs). Key metabolic tissues including liver, adipose tissue, and skeletal muscle express 11β-HSD type 1 (11β-HSD1), which coverts inactive cortisone to active cortisol [11-dehydrocorticosterone (11DHC) and corticosterone (CORT) in rodents, respectively] (8). In the setting of GC excess, the relative contribution to the metabolic effects induced by GCs of simple delivery of active GCs (cortisol or CORT) to a target tissue, compared with the regeneration of active GCs by 11β-HSD1 within the tissue, has not been determined.Type 2 11β-HSD (11β-HSD2) is predominately expressed in the kidney, colon, and salivary gland and catalyzes the inactivation of cortisol to cortisone (CORT to 11DHC in rodents). This not only protects the mineralocorticoid receptor from occupancy by cortisol but also crucially provides substrate for 11β-HSD1 in peripheral tissues.Transgenic animal models have highlighted the critical role of 11β-HSD1 in the regulation of metabolic phenotype in individual tissues. Mice overexpressing 11β-HSD1, specifically in adipose tissue, develop visceral obesity, insulin resistance, dyslipidemia, and hypertension (9, 10). Similarly, liver-specific 11β-HSD1 overexpression results in insulin resistance and hypertension, but not obesity (11). Importantly, circulating CORT levels were not elevated in either model, suggesting increased intracellular GC availability underpins the observed phenotypes. Indeed, this was confirmed in the adipose-specific 11β-HSD1–overexpressing mice, where twofold higher intraadipose CORT levels were recorded in comparison with WT controls (9). Ultimately, this has led to the development of selective 11β-HSD1 inhibitors as a potential treatment for patients with diabetes, obesity, and hypertension (12, 13).Although it is clear that 11β-HSD1 has a critical role to play in governing GC availability, its potential dynamic role in the setting of GC excess has not been fully explored (1416). We have previously reported a patient with Cushing disease who was protected from the classic Cushing phenotype, owing to a functional defect in 11β-HSD1 activity, as evidenced by serum and urinary biomarkers (17). Based on this observation, we have hypothesized that tissue intrinsic 11β-HSD1 activity is the major determinant of the manifestations of GC excess and that 11β-HSD1 deletion will ameliorate the associated metabolic abnormalities. To determine the relative tissue-specific contribution to this effect, we have generated tissue-specific 11β-HSD1 deletions in liver and adipose tissue.  相似文献   
56.
Genetic events underlying pathogenesis of nodal and extranodal marginal zone lymphoma are not completely understood. We report here a novel t(X;14)(p11.4;q32.33) identified in 4 lymphoma cases: 2 with a mucosa-associated lymphoid tissue lymphoma, one with a nodal marginal zone lymphoma and one with gastric diffuse large B-cell lymphoma. In all cases, lymphoma evolved from a previous auto-immune disorder. Fluorescence in situ hybridization and molecular studies showed that t(X;14), which is mediated by immunoglobulin heavy chain locus, targets the GPR34 gene at Xp11.4. Upregulation of GPR34 mRNA and aberrant expression of GPR34 protein has been demonstrated in 3 presented cases by quantitative real-time polymerase chain reaction and immunohistochemistry, respectively. GPR34 belongs to the largest family of cell surface molecules involved in signal transmission that play important roles in many physiological and pathological processes, including tumorigenesis. Although functional consequences of t(X;14) have not been identified, our studies suggest that up-regulated GPR34 activate neither nuclear factor-κB nor ELK-related tyrosine kinase.  相似文献   
57.

Introduction

It is generally assumed that cholesterol reduction by statins is the predominant therapeutic result underlying their beneficial effects in cardiovascular disease. However, the action of statins may be partially independent of their effects on plasma cholesterol levels, as they combine lipid lowering with positive effects on hemorheological conditions and endothelial function. We evaluated the impact of statin treatment on platelet adhesion to fibrinogen (spontaneous and ADP-activated), along with ADP, collagen or ristocetin-induced aggregation in type II hyperlipidemic patients.

Material and methods

The study group included 70 persons: 50 patients affected by type II hyperlipidemia without concomitant diseases and 20 healthy volunteers. The effects of 8-week statin treatment (atorvastatin 10 mg/day, simvastatin 20 mg/day, or pravastatin 20 mg/day) on platelet activation were evaluated.

Results

Regardless of the type of statin, a significant decrease in ADP-induced platelet aggregation was observed: for atorvastatin 50.6 ±12.8% vs. 41.1 ±15.8% (p < 0.05), for simvastatin 57.2 ±18.0% vs. 44.7 ±22.1% (p = 0.05), and for pravastatin 55.8 ±19.5% vs. 38.8 ±23.3% (p < 0.05). There was no significant effect of statins on collagen or ristocetin-induced platelet aggregation and adhesion.

Conclusions

Therapy with statins beneficially modifies ADP-induced platelet aggregation in patients with hyperlipidemia and does not affect spontaneous or ADP-induced platelet adhesion to fibrinogen and platelet aggregation induced by collagen or ristocetin.  相似文献   
58.
59.

Purpose

The aim of the study was to assess bone graft incorporation after revision hip arthroplasty in patients with rheumatoid arthritis (RA).

Methods

We report an acetabular reconstruction using impacted, morselized, frozen, radiation sterilized bone allografts in 71 patients suffering from RA. There were sixty-six women and five men at a mean age of 57.5 years. Reconstruction was performed in 78 revision total hip arthroplasties (THAs) for aseptic loosening of acetabular component. The mean follow-up was five years and four months. In 38 cases, a revision was done with use of reinforcement devices.

Results

In four revised hips (10 %) without reinforcement implants, resorption of the allografts was noticed. All Mueller rings and 50 % of unscrews cages (Link, Howmedica) were revised because of aseptic loosening and bone graft resorption. In all of 17 hips with the Burch-Schneider cage, no measurable migration or bone allografts resorption occurred. There were no major general complications.

Conclusions

Acetabular reconstruction with use of morselized, frozen, radiation sterilized bone allografts and the Burch-Schneider cage can be highly successful in managing massive deficiency of acetabular bone stock in revision hip arthroplasty in RA patients.  相似文献   
60.
Serum levels of lipids and lipoproteins were determined in 98 post-renal transplant fasting patients, and lipids and non-high density lipoprotein-cholesterol (non-HDL-C) and lipid ratios in the same post-renal transplant non-fasting patients were compared. The reference group was 87 healthy subjects. All patients were divided into two groups: patients with dyslipidemia (n?=?69) and patients with normolipidemic (n?=?29). The post-renal transplant patients (TX) with dyslipidemia had a significantly increased concentration of triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), non-HDL-C, apoB, and TRL and lipid ratios, and decreased HDL-C level and lipoprotein ratios. The lipids, lipoproteins, and lipoprotein ratios were significantly beneficial in TX patients with normolipidemic than in those with dyslipidemia. However, TRL concentration and lipid ratios were significantly increased and apoAI/apoCIII significantly decreased as compared to the reference group. The TX patients with dyslipidemia showed a significant correlation between TG and apoB:CIII (r?=?0.562, p < 0.001) and apoCIII (r?=?0.380, p < 0.004), but those with normolipidemic showed a significant correlation only between TG and apoCIII (r?=?0.564, p < 0.008). Regression and Bland-Altman analyses showed excellent correlation between fasting and nonfasting non-HDL-C levels (r?=?0.987, R2 + 0.987) in TX patients both with dyslipidemia and normolipidemic. We think the finding that nonfasting labs that are reliable for non-HDL-C as well as total cholesterol is important, as fasting labs are not always available. Disturbances of lipids, lipoproteins, and TRLs depend not only on the kind of treatment, but due to multiple factors can accelerate cardiovascular complications in post-renal transplant patients with dyslipidemia and also with normolipidemic. Further studies concerning this problem should be completed.  相似文献   
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