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41.
OBJECTIVES: The study was designed to assess the effect of elapsed time from coronary revascularization (CR) on the benefit of the implantable cardioverter-defibrillator (ICD) and the risk of sudden cardiac death (SCD) in patients with ischemic left ventricular dysfunction. BACKGROUND: The ICD improves survival in appropriately selected high-risk cardiac patients by 30% to 54%. However, in the Coronary Artery Bypass Graft (CABG)-Patch trial no evidence of improved survival was shown among a similar population of patients in whom an ICD was implanted prophylactically at the time of elective CABG. METHODS: The outcome by time from CR was analyzed in 951 patients in whom a revascularization procedure was performed before enrollment in the Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II. RESULTS: The adjusted hazard ratio (HR) of ICD versus conventional therapy was 0.64 (p = 0.01) among patients enrolled more than six months after CR, whereas no survival benefit with ICD therapy was shown among patients enrolled six months or earlier after CR (HR = 1.19; p = 0.76). In the conventional therapy group, the risk of cardiac death increased significantly with increasing time from CR (p for trend = 0.009), corresponding mainly to a six-fold increase in the risk of SCD among patients enrolled more than six months after CR. CONCLUSIONS: In patients with ischemic left ventricular dysfunction, the efficacy of ICD therapy after CR is time dependent, with a significant life-saving benefit in patients receiving device implantation more than six months after CR. The lack of ICD benefit when implanted early after CR may be related to a relatively low risk of SCD during this time period.  相似文献   
42.
Introduction: Hereditary hemochromatosis (HH) is an autosomal recessive disorder that occurs in approximately 1 in 200–250 individuals. Mutations in the HFE gene lead to excess iron absorption. Excess iron in the form of non-transferrin-bound iron (NTBI) causes injury and is readily uptaken by cardiomyocytes, pancreatic islet cells, and hepatocytes. Symptoms greatly vary among patients and include fatigue, abdominal pain, arthralgias, impotence, decreased libido, diabetes, and heart failure. Untreated hemochromatosis can lead to chronic liver disease, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Many invasive and noninvasive diagnostic tests are available to aid in diagnosis and treatment. MRI has emerged as the reference standard imaging modality for the detection and quantification of hepatic iron deposition, as ultrasound (US) is unable to detect iron overload and computed tomography (CT) findings are nonspecific and influenced by multiple confounding variables. If caught and treated early, HH disease progression can significantly be altered.

Area covered: The data on Hemochromatosis, iron overload, and MRI were gathered by searching PubMed.

Expert commentary: MRI is a great tool for diagnosis and management of iron overload. It is safe, effective, and a standard protocol should be included in diagnostic algorithms of future treatment guidelines.  相似文献   

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44.
BackgroundThe association of age with coronary plaque dynamics is not well characterized by coronary computed tomography angiography (CCTA).MethodsFrom a multinational registry of patients who underwent serial CCTA, 1153 subjects (61 ± 5 years old, 61.1% male) were analyzed. Annualized volume changes of total, fibrous, fibrofatty, necrotic core, and dense calcification plaque components of the whole heart were compared by age quartile groups. Clinical events, a composite of all-cause death, acute coronary syndrome, and any revascularization after 30 days of the initial CCTA, were also analyzed. Random forest analysis was used to define the relative importance of age on plaque progression.ResultsWith a 3.3-years’ median interval between the two CCTA, the median annual volume changes of total plaque in each age quartile group was 7.8, 10.5, 10.8, and 12.1 mm3/year and for dense calcification, 2.5, 4.6, 5.4, and 7.1 mm3/year, both of which demonstrated a tendency to increase by age (p-for-trend = 0.001 and < 0.001, respectively). However, this tendency was not observed in any other plaque components. The annual volume changes of total plaque and dense calcification were also significantly different in the propensity score-matched lowest age quartile group versus the other age groups as was the composite clinical event (log-rank p = 0.003). In random forest analysis, age had comparable importance in the total plaque volume progression as other traditional factors.ConclusionsThe rate of whole-heart plaque progression and dense calcification increases depending on age. Age is a significant factor in plaque growth, the importance of which is comparable to other traditional risk factors.Clinical trial registrationURL: http://www.clinicaltrials.gov. Unique identifiers: NCT02803411.  相似文献   
45.
Ovarian carcinoma patients are initially responsive to platinum-based therapy, but eventually become refractory to treatment due to the development of platinum chemoresistance. Elevated levels of interleukin-6 (IL-6) in the sera and ascites of these patients predict poor clinical outcome. Our goal was to analyze the interaction between cisplatin and cisplatin-resistant ovarian cancer cells, and to identify means of circumventing platinum resistance. We studied ovarian carcinoma cell lines and cells drawn from ovarian carcinoma patients. Gene array analyses were performed on ovarian carcinoma cells upon treatment with cisplatin, and the results were validated by ELISA and Western blotting (WB). Cytotoxicity assays were performed on anti-IL-6 Ab-, IL-6-, and cellular inhibitor of apoptosis 2 (cIAP-2) siRNA-treated cells, following cisplatin addition. Our results revealed a highly significant increase in IL-6 and cIAP-2 mRNA and protein levels upon treatment with cisplatin. WB analysis of cisplatin-treated cells exhibited decreased cIAP-2 expression level following anti-IL-6 Ab addition. Furthermore, IL-6 by itself, significantly increased cIAP-2 levels in ovarian carcinoma cells. Finally, cytotoxicity assays showed sensitization to cisplatin following the addition of IL-6 and cIAP-2 inhibitors. In conclusion, cisplatin treatment of ovarian carcinoma cells upregulates IL-6 and cIAP-2 levels while their inhibition significantly sensitizes them to cisplatin. Here, we present cIAP-2 as a novel inducer of platinum resistance in ovarian carcinoma cells, and suggest an axis beginning with an encounter between cisplatin and these cells, mediated sequentially by IL-6 and cIAP-2, resulting in cisplatin resistance. Consequently, we propose that combining IL-6/cIAP-2 inhibitors with cisplatin will provide new hope for ovarian carcinoma patients by improving the current treatment.  相似文献   
46.
IntroductionHypertension is a common major systemic disease and 1 of the most significant causes of mortality worldwide. Persistent hypertension is 1 of the risk factors for stroke, heart attack, heart failure, and arterial aneurysm and is a leading cause of chronic kidney failure. Common medications used to treat hypertension include beta blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and calcium channel blockers. The purpose of this study was to assess the prevalence of periapical abscesses in patients with different types of hypertension conditions and to evaluate the effect of commonly used antihypertensive medications on the prevalence of periapical abscesses.MethodsThe integrated data of hospital patients were used. Data from the corresponding diagnosis codes for hypertensive conditions and periapical abscess were retrieved by searching the appropriate query in the database. The odds ratio (OR) of periapical abscesses, its association with hypertensive conditions, and the intake of 4 antihypertensive medications were calculated and analyzed statistically.ResultsThe prevalence of periapical abscesses in patients with hypertensive conditions was 1.2% compared with 0.558% in the general patient population of the hospital. The OR for the prevalence of periapical lesions in patients with hypertension was 2.32. For primary hypertension, the OR was 2.02; for hypertensive heart disease, the OR was 2.68; for hypertensive chronic kidney disease, the OR was 2.1; for hypertensive heart and chronic kidney diseases, the OR was 4.16; for secondary hypertension, the OR was 4.16; and for hypertension crisis, the OR was 5.64. For patients treated with beta blockers, the OR was 2.58; for patients treated with angiotensin-converting enzyme inhibitors, the OR was 2.73; for patients treated with angiotensin II receptor blockers, the OR was 1.93; and for patients treated with calcium channel blockers, the OR was 2.79. The differences were statistically significant (P < .0001). The OR for the prevalence of periapical abscesses in patients treated with angiotensin II receptor blockers was significantly lower than that of patients treated with either beta blockers or calcium channel blockers (P < .00001).ConclusionsUnder the conditions of this study, it appears that the prevalence of perapical abscesses is significantly higher in hypertensive patients. The prevalence of periapical abscesses is higher in patients with secondary hypertension than in those with primary hypertension. Angiotensin II receptor blockers may significantly lower the prevalence of periapical abscesses in hypertensive patients.  相似文献   
47.
The bioenergetic capacity of skeletal muscle in a 17-year-old patient with a severe defect in complex III of the electron transport chain has been examined by 31P NMR measurements of the molar ratio of phosphocreatine to inorganic phosphate (PCr/Pi). Resting ratios were 1.3-2.5, which can be compared with roughly 8.6 for a young, normal female control at rest. Quantitative evaluation of the activity of oxidative metabolism was afforded by the rate of recovery of PCr/Pi from exercise and was found to be 2.5% of normal. After administration of menadione and ascorbate, we found a 21-fold increase of the recovery rate relative to the pretherapy value, to within 56% of the recovery rate of the young female control. Thus, NMR examinations of skeletal muscle at rest and in recovery from activity document marked improvement to specific drug therapy in the electron transport capabilities and the ATP synthesis rate of a patient with a deficiency in a cytochrome b-containing complex III. Improvements in functional ability, although not as dramatic as biochemical changes, are also apparent.  相似文献   
48.
Uterine lymphoma is rare and tends to be misdiagnosed due to lack of specific radiologic features. Few reports have been published on the sonographic characteristics of uterine lymphoma. We present a case report of uterine lymphoma manifested by a fast growing uterus and describe the sonographic findings. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound, 43 :59–63, 2015  相似文献   
49.
Adenosquamous carcinomas of the head and neck (ADSCs) are rare locally aggressive malignancies characterized by the presence of two distinctive components, a squamous cell carcinoma and an adenocarcinoma. The immunophenotype of the glandular component of ADSCs has only been rarely studied but has been reported as being positive for keratin 7 (CK7) and carcinoembryonic antigen (CEA) and negative for keratin 20 (CK20). Herein, we report a case of an ADSCs of the hypopharynx composed of a superficial squamous cell carcinoma and an adenocarcinoma with an intestinal phenotype. The patient was a 62 year-old male with a T2 N0 M0 squamous cell carcinoma (SCC) of uvula and palate and a T1 N0 M0 of right hypopharynx. The ADSCs of the hypopharynx was composed of a minimally invasive SCC and an adenocarcinoma with tubulo-glandular and cribriform architecture. The neoplastic glands were positive for CK7, CK20, CDX2, CEA and Villin. The patient underwent radiotherapy to both tumors and remains well with no evidence of recurrent disease 19 months after treatment. To the best of our knowledge, this is the first report of an ADSCs of the head and neck with an intestinal phenotype in its glandular component.  相似文献   
50.
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