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991.
992.
Tumor necrosis factor alpha (TNFalpha) plays a key role in orchestrating the complex events involved in inflammation and immune response. The presence of single nucleotide polymorphisms (SNPs) within the promoter region of the TNFa gene has been associated with a number of diseases. The aim of this study was to investigate the distribution of polymorphisms at positions -238 (G/A) and -308 (G/A) at the TNFalpha promoter, and its association to the outcome of different clinical forms of leprosy. Furthermore, the bacteriological index (BI) was evaluated among genotyped multibacillary (MB) patients in order to investigate the possible influence of each polymorphism on the bacterial load. This study included a total of 631 leprosy patients being 401 MB and 230 paucibacillary (PB), that was further separated according to its ethnicity (Afro- and Euro-Brazilians). The combination of SNPs in haplotypes generated three different arrangements: TNFG-G, TNFG-A and TNFA-G. In spite of the marked differences observed in the frequency of the haplotypes along the ethnic groups, no statistical differences were observed in haplotype frequencies between MB and PB patients. The BI analyses showed a lower bacteriological index among the -308 carriers, while the BI of the -238 carriers was higher. Although no significance has been achieved in this analysis regarding the influence of the polymorphisms to the development of the clinical outcome, it seems that in a different stage (among the MB patients) the polymorphisms could contribute to the degree of severity observed.  相似文献   
993.

Introduction

Our objective was to characterize the enzymatic β-lactam resistance in clinical Enterobacteriaceae isolates with diminished susceptibility to carbapenems from 2013 to 2014 at Hospital Universitario Miguel Servet.

Material/methods

A total of 63 clinical isolates were analyzed for the presence of carbapenemases (KPC, OXA-48 and MBL), ESBLs and AmpC enzymes by combined disk methods and PCR detection of carbapenemase-encoding and beta-lactamase-encoding genes.

Results

Fifteen isolates had a phenotypic test compatible with carbapenemase production; two of these were confirmed by PCR as OXA-48 producers. ESBL detection was positive in 27 isolates (43%); plasmid-mediated AmpC was detected in nine isolates (14.2%) and derepressed AmpC β-lactamase was present in 18 isolates (28%).

Conclusion

During the study period, the decreased susceptibility to carbapenems in Enterobacteriaceae in our area was not due to true carbapenemases but rather to β-lactamase activity (82.5% were ESBL or AmpC producers), probably in combination with decreased permeability of the outer membrane.  相似文献   
994.

Introduction and objectives

Multidetector computed tomography (MDCT) has been demonstrated as a feasible alternative to invasive coronary angiography (ICA). However, contradictory results have been reported regarding the effect of coronary artery calcium score (CS) on the diagnostic accuracy of MDCT. Our aim was to assess the agreement of MDCT and ICA and to evaluate the influence of CS on this agreement.

Methods

We enrolled 266 consecutive patients who underwent evaluation with 64-slice MDCT and ICA. Standard CS software tools were used to calculate the Agatston score. Stenosis was qualitatively classified as mild, moderate, or severe by 1 blinded observer and the results were compared with those of ICA, which was used as the gold standard.

Results

The mean age of the patients was 65.4 ± 11.2 years, and 188 patients (70.3%) were men. A total of 484 segments with coronary stenosis ≥ mild were qualitatively evaluated and quantified with MDCT. Noninvasive measurements were concordant with ICA in 402 stenoses (83.05%; Kappa, 0.684), with no significant differences between vessels and with no statistically significant influence of CS on this agreement (OR, 0.93; 95%CI, 0.76-1.09; P = .21). Multidetector computed tomography had high sensitivity, specificity, positive predictive value, and negative predictive value on a per-segment, per-vessel, and per-patient basis.

Conclusions

Non-ICA using MDCT showed good agreement with ICA in the qualitative quantification coronary stenosis and CS had no significant impact on this agreement.Full English text available from: www.revespcardiol.org/en  相似文献   
995.

Background and objective

Online haemodiafiltration (OL-HDF) with high convective transport volumes improves patient survival in haemodialysis. Limiting the amount of convective volume has been proposed in patients with diabetes mellitus due to glucose load that is administered with replacement fluid. The objective of the study was to analyse the influence of substitution volume on the evolution of the metabolic profile and body composition of incident diabetic patients on OL-HDF.

Material and methods

Prospective observational study in 29 incident diabetic patients on postdilution OL-HDF. Baseline data included clinical and demographic data, laboratory parameters (metabolic, nutritional and inflammatory profile) and body composition with bioimpedance spectroscopy (BIS). Laboratory parameters and mean substitution volume per session were collected every 4 months, and in 23 patients a further BIS was performed after a minimum of one year. Variations in glycosylated haemoglobin (HbA1c), triglycerides, total cholesterol, LDL-c, HDL-c, albumin, prealbumin and C reactive protein (CRP) were calculated at one year, 2 years, 3 years, and at the end of follow-up. Quarterly and annual variations were calculated as independent periods, and changes in body composition were analysed.

Results

Age at baseline was 69.7 ± 13.6 years, 62.1% were male, 72.3 ± 13.9 kg, 1.78 ± 0.16 m2, with 48 (35.5-76) months on dialysis. Approximately 81.5% received insulin, 7.4% antidiabetic drugs and 51.9% statins. Mean substitution volume was 26.9 ± 2.9 L/session and follow-up period (time on OL-HDF) was 40.4 ± 26 months.A significant correlation was observed between mean substitution volume and the increase in HDL-c (r = 0.385, p = 0.039) and prealbumin levels (r = 0.404, p = 0.003) throughout follow-up. Moreover, substitution volume was correlated with a reduction in CRP levels at one year (r = –0.531, p = 0.005), 2 years (r = –0.463, p = 0.046), and at the end of follow-up (r = –0.498, p = 0.007). Patients with mean substitution volume > 26.9 L/session had a higher reduction in triglycerides and CRP, and an increase in HDL-c levels. These patients with > 26.9 L/session finished the study with higher HDL-c (48.1 ± 9.4 mg/dL vs. 41.2 ± 11.6 mg/dL, p = 0.025) and lower CRP levels (0.21 [0.1-2.22] mg/dL vs. 1.01 [0.15-6.96] mg/dL, p = 0.001), with no differences at baseline.Quarterly comparisons between substitution volume and laboratory changes [n = 271] showed a significant correlation with a reduction in HbA1c (r = –0.146, p = 0.021). Similar findings were obtained with annual comparisons [n = 72] (r = –0.237, p = 0.045). An annual mean substitution volume over 26.6 L/session (29.3 ± 1.7 L/session vs. 23.9 ± 1.9 L/session) was associated with a reduction in HbA1c (–0.51 ± 1.24% vs. 0.01 ± 0.88%, p = 0.043). No correlation was observed between substitution volume and changes in weight, body mass index or BIS parameters.

Conclusion

There is not enough evidence to restrict convective transport in diabetic patients on OL-HDF due to the glucose content of the replacement fluid.  相似文献   
996.
Eosinophilic esophagitis is a rare, recently discovered disease, characterized by esophageal symptoms, such as dysphagia and food impaction, associated with dense eosinophilia on endoscopic biopsy of the esophagus. Other entities such as gastroesophageal reflux disease are absent and there is a lack of response to proton pump inhibitor therapy. This disease mainly affects the pediatric population but is becoming more prevalent in adults. There are several theories on the etiopathogenesis of this entity, which may involve allergies and atopy. In advanced disease, complications such as esophageal stenosis can appear. Treatment is based on dietary elimination, corticosteroids and endoscopic dilatation. We report a case of eosinophilic esophagitis with esophageal stenosis.  相似文献   
997.

Introduction and objectives

Hereditary pulmonary veno-occlusive disease (PVOD) has been associated with biallelic mutations in EIF2AK4 with the recent discovery of a founder mutation in Iberian Romani patients with familial PVOD. The aims of this study were phenotypical characterization and survival analysis of Iberian Romani patients with familial PVOD carrying the founder p.Pro1115Leu mutation in EIF2AK4, according to their tolerance to pulmonary vasodilators (PVD). Familial genetic screening was conducted, as well as assessment of sociocultural determinants with a potential influence on disease course.

Methods

Observational study of Romani patients with familial PVOD included in the Spanish Registry of Pulmonary Arterial Hypertension. Genetic screening of EIF2AK4 was performed in index cases and relatives between November 2011 and July 2016 and histological pulmonary examination was carried out in patients who received a lung transplant or died. The patients were divided into 2 groups depending on their tolerance to PVD, with comparison of baseline characteristics and survival free of death or lung transplant.

Results

Eighteen Romani patients were included: 9 index cases and 9 relatives. The biallelic founder mutation in EIF2AK4 was found in all affected cases and 2 unaffected relatives. Family screening showed 34.2% of healthy heterozygotes, high consanguinity, young age at childbirth, and frequent multiparity. Prognosis was bleak, with significant differences depending on tolerance to PVD.

Conclusions

We describe 2 phenotypes of hereditary PVOD depending on tolerance to PVD, with prognostic impact and familial distribution. Consanguinity may have a negative impact on the transmission of PVOD, with familial genetic screening showing high effectiveness.Full English text available from: www.revespcardiol.org/en  相似文献   
998.
Quality of Life in Functional Dyspepsia   总被引:1,自引:0,他引:1  
Our purpose was to assess the quality of life of functional dyspepsia patients using the SF-36 generic scale and the Gastrointestinal Symptoms Rating Scale (GSRS). In all, 328 dyspeptic patients were included in a multicenter, prospective, observational study. Both scales were filled out at baseline and one and three months after a prokinetic agent was given as a single-drug therapy. A total of 250 patients completed the study. An improvement in all SF-36 dimensions was observed, although the final scores were lower than the population reference values. Physical role (27% change), emotional role (20%), and physical pain (16%) dimensions showed the greater change. The GSRS total and domain scores also showed significant decreases. The best predictors of quality of life improvement were certain basal symptoms, drug compliance, and the absence of idiopathic dyspepsia. In conclusion, both the generic and the specific scales provide useful and sensitive measures of quality of life in functional dyspepsia patients on single-drug treatment.  相似文献   
999.
Repeated psychosocial or restraint stress causes atrophy of apical dendrites in CA3 pyramidal neurons of the hippocampus, accompanied by specific cognitive deficits in spatial learning and memory. Excitatory amino acids mediate this atrophy together with adrenal steroids and the neurotransmitter serotonin. Because the mossy fibers from dentate granule neurons provide a major excitatory input to the CA3 proximal apical dendrites, we measured ultrastructural parameters associated with the mossy fiber–CA3 synapses in control and 21-day restraint-stressed rats in an effort to find additional morphological consequences of stress that could help elucidate the underlying anatomical as well as cellular and molecular mechanisms. Although mossy fiber terminals of control rats were packed with small, clear synaptic vesicles, terminals from stressed animals showed a marked rearrangement of vesicles, with more densely packed clusters localized in the vicinity of active zones. Moreover, compared with controls, restraint stress increased the area of the mossy fiber terminal occupied by mitochondrial profiles and consequently, a larger, localized energy-generating capacity. A single stress session did not produce these changes either immediately after or the next day following the restraint session. These findings provide a morphological marker of the effects of chronic stress on the hippocampus that points to possible underlying neuroanatomical as well as cellular and molecular mechanisms for the ability of repeated stress to cause structural changes within the hippocampus.  相似文献   
1000.
Central Core Disease (CCD) is an inherited neuromuscular disorder characterized by the presence of cores in muscle biopsy. CCD is caused by mutations in the RYR1 gene. This gene encodes the ryanodine receptor 1, which is an intracellular calcium release channel from the sarcoplasmic reticulum to the cytosol in response to depolarization of the plasma membrane. Mutations in this gene are also associated with susceptibility to Malignant Hyperthermia (MHS).In this study, we evaluated 20 families with clinical and histological characteristics of CCD to identify primary mutations in patients, for diagnosis and genetic counseling of the families.We identified variants in the RYR1 gene in 19/20 families. The molecular pathogenicity was confirmed in 16 of them. Most of these variants (22/23) are missense and unique in the families. Two variants were recurrent in two different families. We identified six families with biallelic mutations, five compound heterozygotes with no consanguinity, and one homozygous, with consanguineous parents, resulting in 30% of cases with possible autosomal recessive inheritance. We identified seven novel variants, four of them classified as pathogenic. In one family, we identified two mutations in exon 102, segregating in cis, suggesting an additive effect of two mutations in the same allele.This work highlights the importance of using Next-Generation Sequencing technology for the molecular diagnosis of genetic diseases when a very large gene is involved, associated to a broad distribution of the mutations along it. These data also influence the prevention through adequate genetic counseling for the families and cautions against malignant hyperthermia susceptibility.Key words: central core disease, RYR1, Next Generation Sequencing  相似文献   
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