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21.
Poststreptococcal reactive arthritis (PSRA) is an acute, nonsuppurative arthritis following documented streptococcal infections. Although most authors accepted it as a different entity, the differences from acute rheumatic fever (ARF) are not clear. To document and compare the clinical and laboratory characteristics of PSRA and ARF, 24 patients with PSRA and 20 with ARF were enrolled in the study. The latency period from upper respiratory tract infection was shorter in patients with PSRA ( P<0.01). However, 25% of the patients with ARF had also short (<10 days) latency periods. Although symmetric and nonmigratory arthritis were more frequent in patients with PSRA, there was no significant difference for the distribution of mono-, oligo-, and polyarticular disease between PSRA and ARF patients. The frequency of small joint and hip involvement was also similar between the patient groups. Unresponsiveness of articular symptoms to salicylate therapy within 72 h was more frequent in patients with PSRA (P<0.001). However, in a substantial part of the patients with ARF (nine patients, 45%), joint symptoms also had no response during the first 72 h. Since there is a considerable overlap of symptoms, signs, and laboratory features of PSRA and ARF, a line between these two entities could not be easily drawn. We conclude that these two conditions are actually different presentations of the same disease.  相似文献   
22.
Chemical penetration enhancers (CPEs) are present in a large number of transdermal, dermatological, and cosmetic products to aid dermal absorption of curatives and aesthetics. This wide spectrum of use is based on only a handful of molecules, the majority of which belong to three to four typical chemical functionalities, sporadically introduced as CPEs in the last 50 years. Using >100 CPEs representing several chemical functionalities, we report on the fundamental mechanisms that determine the barrier disruption potential of CPEs and skin safety in their presence. Fourier transform infrared spectroscopy studies revealed that regardless of their chemical make-up, CPEs perturb the skin barrier via extraction or fluidization of lipid bilayers. Irritation response of CPEs, on the other hand, correlated with the denaturation of stratum corneum proteins, making it feasible to use protein conformation changes to map CPE safety in vitro. Most interestingly, the understanding of underlying molecular forces responsible for CPE safety and potency reveals inherent constraints that limit CPE performance. Reengineering this knowledge back into molecular structure, we designed >300 potential CPEs. These molecules were screened in silico and subsequently tested in vitro for molecular delivery. These molecules significantly broaden the repertoire of CPEs that can aid the design of optimized transdermal, dermatological, and cosmetic formulations in the future.  相似文献   
23.
AIM/BACKGROUND: Achalasia may be associated with extraesophageal dysmotility. However, this relation is still poorly understood. In the present study, we used noninvasive real-time ultrasonography to examine the motility function of the gallbladder in the patients with achalasia. MATERIALS AND METHODS: Thirty-three achalasic patients and 33 healthy volunteers were included in the study. All subjects were investigated after 12 hours of fasting and 30 minutes after a standard test meal. Premeal and postmeal gallbladder volumes were used for calculation of the ejection fraction of the gallbladder and fasting gallbladder volume. RESULTS: The mean fasting volume (18.52+/-1.45 vs. 24.63+/-1.84 cm; P<0.05) and ejection fractions of gallbladder (35.84+/-4.12 vs. 54.47+/-2.47; P<0.05) in the patients with achalasia were lower than the control group. CONCLUSIONS: Such a finding may confirm the possible extraesophageal extension of primary achalasia. Achalasic patients have smaller gallbladders than do others. It could be speculated that it is congenital and/or achalasic patients' gallbladder has incomplete relaxation (as in the lower esophageal sphincter of the achalasia).  相似文献   
24.

OBJECTIVES:

To evaluate the clinical outcomes and identify the predictors of mortality in elderly patients undergoing peritoneal dialysis.

METHODS:

We conducted a retrospective study including all incident peritoneal dialysis cases in patients ≥65 years of age treated from 2001 to 2014. Demographic and clinical data on the initiation of peritoneal dialysis and the clinical events during the study period were collected. Infectious complications were recorded. Overall and technique survival rates were analyzed.

RESULTS:

Fifty-eight patients who began peritoneal dialysis during the study period were considered for analysis, and 50 of these patients were included in the final analysis. Peritoneal dialysis exchanges were performed by another person for 65% of the patients, whereas 79.9% of patients preferred to perform the peritoneal dialysis themselves. Peritonitis and catheter exit site/tunnel infection incidences were 20.4±16.3 and 24.6±17.4 patient-months, respectively. During the follow-up period, 40 patients were withdrawn from peritoneal dialysis. Causes of death included peritonitis and/or sepsis (50%) and cardiovascular events (30%). The mean patient survival time was 38.9±4.3 months, and the survival rates were 78.8%, 66.8%, 50.9% and 19.5% at 1, 2, 3 and 4 years after peritoneal dialysis initiation, respectively. Advanced age, the presence of additional diseases, increased episodes of peritonitis, the use of continuous ambulatory peritoneal dialysis, and low albumin levels and daily urine volumes (<100 ml) at the initiation of peritoneal dialysis were predictors of mortality. The mean technique survival duration was 61.7±5.2 months. The technique survival rates were 97.9%, 90.6%, 81.5% and 71% at 1, 2, 3 and 4 years, respectively. None of the factors analyzed were predictors of technique survival.

CONCLUSIONS:

Mortality was higher in elderly patients. Factors affecting mortality in elderly patients included advanced age, the presence of comorbid diseases, increased episodes of peritonitis, use of continuous ambulatory peritoneal dialysis, and low albumin levels and daily urine volumes (<100 ml) at the initiation of peritoneal dialysis.  相似文献   
25.

OBJECTIVES:

The aim of our study was to evaluate the total atrial conduction time and its relationship to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus.

METHODS:

A total of 132 patients with type 2 diabetes mellitus (mean age 54.5±9.6 years; 57.6% male) and 80 age- and gender-matched controls were evaluated. The total atrial conduction time was measured by tissue-Doppler imaging and the carotid intima-media thickness was measured by B-mode ultrasonography.

RESULTS:

The total atrial conduction time was significantly longer in the patients with type 2 diabetes mellitus than in the control group (131.7±23.6 vs. 113.1±21.3, p<0.001). The patients with type 2 diabetes mellitus had significantly increased carotid intima-media thicknesses, neutrophil to lymphocyte ratios and high-sensitivity C-reactive protein levels than those of the controls. The total atrial conduction time was positively correlated with the high-sensitivity C-reactive protein level, neutrophil to lymphocyte ratio, carotid intima-media thickness and left atrial volume index and negatively correlated with the early diastolic velocity (Em), Em/late diastolic velocity (Am) ratio and global peak left atrial longitudinal strain. A multiple logistic regression analysis demonstrated that the neutrophil to lymphocyte ratio, carotid intima-media thickness and global peak left atrial longitudinal strain were independent predictors of the total atrial conduction time.

CONCLUSIONS:

We suggest that subclinical atherosclerosis and inflammation may represent a mechanism related to prolonged total atrial conduction time and that prolonged total atrial conduction time and impaired left atrial myocardial deformation may be represent early subclinical cardiac involvement in patients with type 2 diabetes mellitus.  相似文献   
26.
27.
Objective: Isolated growth hormone deficiency (IGHD) is defined as a medical condition associated with growth failure due to insufficient production of GH or lack of GH action. Mutations in the gene encoding for GH-releasing hormone receptor (GHRHR) have been detected in patients with IGHD type IB. However, genetic defects on GHRHR causing IGHD in the Turkish population have not yet been reported. To identify mutations on GHRHR gene in a population of Turkish children with IGHD.Methods: Ninety-six Turkish children with IGHD were included in this study. Exon1-13 and exon/intron boundaries of GHRHR were amplified by suitable primers. The polymerase chain reaction products for GHRHR gene were sequenced with primers.Results: We analyzed the GHRHR gene for mutations in ninety-six patients with IGHD based on sequence results. We identified novel p.K264E, p.S317T, p.S330L, p.G369V, p.T257A and C base insertion on position 380 (c.380inserC) mutations. In 5 of the patients, the mutation was homozygote and in 1-heterozygote (p.S317T).Conclusion: Six new missense mutations and one first case of insertion mutations for the GHRHR gene are reported.  相似文献   
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Thoracic radiography and high resolution computerized tomography is used to diagnose pulmonary infections in immunosuppressed patients, although in some cases these do not provide enough information about the lesion. Dynamic contrast‐enhanced magnetic resonance imaging may be useful in these cases, especially for the characterization of cavitary lesions and assessment of their contrast diffusion.  相似文献   
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