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991.
Cardiac sympathetic activity can be assessed by (123)I-labelled meta-iodobenzylguanidine (MIBG) scintigraphy. Abnormalities of sympathetic cardiac activity have been shown in patients with heart failure, resulting in reduced MIBG uptake. Abnormal MIBG uptake predicts cardiac death, arrhythmias and all-cause mortality in patients with heart failure with a prognostic power incremental to that of conventional risk markers, and may identify patients at low risk of arrhythmias despite current guideline indications for implantable cardioverter defibrillator or patients at high risk for arrhythmias not fulfilling implantable cardioverter defibrillator indications. Prospective outcome studies are needed to assess whether MIBG imaging will have an impact on the mortality and morbidity of patients with heart failure.  相似文献   
992.

Background

Detection of Streptococcus pneumoniae C-polysaccharide in urine is a useful rapid diagnostic test for pneumococcal infections in adults. In young children, high rates of false positive results have been documented due to detection of concurrent nasopharyngeal pneumococcal carriage. The relationship between pneumococcal carriage and urinary antigen detection in adults from developing countries with high pneumococcal carriage prevalence has not been well established.

Methods

We nested an evaluation of the BinaxNOW S. pneumoniae test within a longitudinal mother-infant pneumococcal carriage study in Karen refugees on the Thailand-Myanmar border. Paired urine and nasopharyngeal swab specimens were collected from 98 asymptomatic women at a routine study follow-up visit. The urine specimens were analyzed with the BinaxNOW test and the nasopharyngeal swabs were semi-quantitatively cultured to identify pneumococcal colonization.

Results

24/98 (25%) women were colonized by S. pneumoniae but only three (3%) had a positive BinaxNOW urine test. The sensitivity of the BinaxNOW test for detection of pneumococcal colonization was 4.2% (95% CI: 0.1 - 21.1%) with a specificity of 97.3% (95% CI: 90.6 - 99.7%). Pneumococcal colonization was not associated with having a positive BinaxNOW test (odds ratio 1.6; 95% CI: 0.0 - 12.7; p = 0.7).

Conclusions

Significant numbers of false positive results are unlikely to be encountered when using the BinaxNOW test to diagnose pneumococcal infection in adults from countries with moderate to high rates of pneumococcal colonization.  相似文献   
993.
Background and aim: The PNPLA3 rs738409 C>G polymorphism has been found to be strongly associated with non‐alcoholic fatty liver disease and with alcoholic liver disease. Whether the PNPLA3 rs738409 polymorphism could be a risk factor for the development of hepatocellular carcinoma (HCC) in cirrhosis patients is unknown. Methods: This study included 483 (344 males) consecutive Italian patients of Caucasian ethnicity affected by cirrhosis, of whom 279 had undergone transplantation for end‐stage liver disease while 204 had been referred to our liver and transplant unit for the diagnosis of cirrhosis. The aetiologies were hepatitis C virus=209, hepatitis B virus=76, alcohol=166, metabolic=32. Ile148Met rs738409 transversion was genotyped using an restriction fragment length polymorphism‐based assay. Results: The genotype frequencies of the rs738409 polymorphism were distributed differently in patients with cirrhosis C/C=168, C/G=220, G/G=95 vs controls C/C=218, C/G=175, G/G=35 (P<0.0001). Among cirrhotics, the G allele was over‐represented in alcoholic/metabolic (0.505) vs viral (0.368, P<0.001) liver disease. Patients with cirrhosis complicated by HCC were more likely to be G/G homozygotes (38/141) than the remaining patients (57/342, P<0.02). At multivariate analysis, the PNPLA3 rs738409 polymorphism was confirmed to be an independent predictor of HCC occurrence (odds ratio 1.76, 95% confidence interval 1.06–2.92, P<0.05). HCC rates increased from 13/116 (11.2%; female C/* carriers), to 97/295 (32.9%; male C/*carriers and female G/G homozygotes), to 31/72 (43.1%; male G/G homozygotes) (P<0.0001). Conclusions: The PNPLA3 rs738409 C>G polymorphism is associated with cirrhosis. In synergy with gender, this polymorphism is a strong predictor of HCC occurrence among patients with cirrhosis.  相似文献   
994.
995.
Patients with a partial reduction of merosin due to mutations in the laminin‐α2 chain gene usually present with a mild form of congenital muscular dystrophy or a limb‐girdle–like muscular dystrophy. To our knowledge, cardiac impairment has never been reported in such patients. A longitudinal study of a patient with partial laminin‐α2 deficiency secondary to mutations in the LAMA2 gene revealed dilated cardiomyopathy with ventricular arrhythmias. Is this a chance association or a novel phenotype? Muscle Nerve, 2011  相似文献   
996.
Oxidative stress and immune/inflammatory responses are key pathogenetic factors of atherosclerotic disease. In this contest, mechanisms that regulate survival and death of immune cells may be relevant. Previous studies have demonstrated that red blood cells (RBCs) are physiologically able to inhibit apoptosis and to promote proliferation of activated T lymphocytes from healthy subjects. The aim of the present study was to evaluate whether RBCs from patients with carotid atherosclerosis maintain their property to modulate T cell homeostasis. Peripheral blood lymphocytes (PBLs) obtained from healthy subjects were activated in vitro by phytohemagglutinin in the presence/absence of RBCs from patients with carotid atherosclerosis or of in vitro oxidised RBCs from healthy subjects. Levels of reactive oxygen species (ROS) and aging markers of RBCs as well as susceptibility to apoptosis of PBLs were evaluated by flow cytometry. PBL proliferation was evaluated by 3H-methyl-thymidine incorporation assay whereas secretion of cytokines, analysed in view of their key role in T cell function, was assessed by ELISA. Levels of ROS and phosphatidyl-serine externalisation, a sign of RBC aging, resulted significantly higher in RBCs from patients than in those from healthy subjects, whereas surface glycophorin A expression and reduced glutathione content did the opposite. Unlike RBCs obtained from healthy subjects, RBCs from patients and in vitro oxidised RBCs did not protect activated T lymphocytes from apoptosis. Hence, RBCs from patients with carotid atherosclerosis, probably due to their oxidative imbalance, impact T cell integrity and function. Our results suggest a new regulatory role for RBCs in atherosclerosis.  相似文献   
997.
Inherited severe hypoplasminogenaemia is a multisystemic disorder leading to deficient extravascular fibrinolysis. As a clinical consequence wound healing capacity of mucous membranes is markedly impaired leading to ligneous conjunctivitis and several other manifestations. Here we report the molecular genetic and clinical findings on 23 new cases with severe hypoplasminogenaemia. Homozygous or compound-heterozygous mutations in the plasminogen (PLG) gene were found in 16 of 23 patients (70%), three of which were novel mutations reported here for the first time (C166Y, Y264S, IVS10-7T/G). Compared to 79 previously published cases, clinical manifestations of the current group of patients showed higher percentages of ligneous periodontitis, congenital hydrocephalus, and involvement of the female genital tract. In contrast, involvement of the gastrointestinal or urogenital tract was not observed in any of the cases. Patients originated to a large extent (61%) from Turkey and the Middle East, and showed a comparably frequent occurrence of consanguinity of affected families and a greater female to male ratio than was derived from previous reports in the literature. Individual treatment of ligneous conjunctivitis included topical plasminogen or heparin eye drops, topical or systemic fresh frozen plasma, and surgical removal of ligneous pseudomembranes, mostly with modest or transient efficacy. In conclusion, the present study underscores the broad range of clinical manifestations in PLG-deficient patients with a trend to regional differences. Transmission of genetic and clinical data to the recently established Plasminogen Deficiency Registry should help to determine the prevalence of the disease and to develop more efficient treatment strategies.  相似文献   
998.
999.

Background

The growing teratoma syndrome (GTS) consists of a mature teratoma paradoxically enlarging during or after chemotherapy for malignant nongerminomatous germ cell tumors.

Methods and results

We report two cases of GTS occurring in association with NSGCT of the pineal gland. Although an unusual event, clinicians and radiologists should be aware of its natural history.

Conclusions

When normalized tumor markers after chemotherapy are associated with imaging features of a growing mass, the hypothesis of GTS must be taken in consideration. When early diagnosed, GTS can be managed surgically with good results.  相似文献   
1000.
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