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The objective of this study was to investigate the healing effect of five different products on split‐thickness skin graft (STSG) donor sites and full‐thickness cutaneous wounds (FTCWs) using an occlusive dressing model. Six groups were included: 1 control and 5 experimental groups, with a total of 24 rats, using an occlusive dressing model. STSG donor sites and FTCWs were established in two separate areas, to the right and left on the animals' backs. Wound sites were dressed with one of the following materials: fine mesh gauze, microporous polysaccharide hemosphere (MPH), clinoptilolite, alginate, hydrogel or biosynthetic wound dressing (Biobran®). These materials were compared in terms of healing rate, healing quality and histopathological findings. Occlusive dressings were applied to each wound on days 0, 3, 5, 7, 10 and 14. Area measurements were taken using images of each dressing. The alginate and clinoptilolite groups gave the best healing rate results for both STSG donor sites (P = 0·003) and FTCWs (P = 0·003). MPH came third in each group. The alginate group produced better results in terms of healing quality criteria, followed by hydrogel, MPH, clinoptilolite and Biobran®, in that order. Statistically significant results were obtained in all groups compared to the control group (P < 0·0007). Rapid and good healing quality for both the STSG donor sites and FTCWs were obtained with alginate. Healing with clinoptilolite and MPH was rapid, but poor quality, while slower but good healing quality was obtained with hydrogel. Slower and worse quality healing was obtained with Biobran®.  相似文献   
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ObjectiveVaso-occlusive crisis (VOC) is a common clinical manifestation of sickle cell anemia (SCA) and is associated with increased proinflammatory mediators. Copeptin is the C-terminal part of the prohormone for provasopressin and seems clinically relevant in various clinical conditions. Right ventricular (RV) dysfunction significantly appears in SCA patients due to pulmonary hypertension. This study aimed to investigate the association of copeptin levels in VOC patients and evaluate RV dysfunction.Materials and MethodsA total of 108 patients were enrolled in the study. Twenty-eight SCA patients in steady state (30.2 ± 0.9 years), 25 SCA patients in VOC (36.8 ± 11.8 years), and 55 healthy individuals (31.9 ± 9.4 years) with HbAA genotype were included. Clinical, echocardiographic, and laboratory data were recorded. ELISA was used for the determination of serum levels of copeptin.ResultsVOC patients had significantly higher copeptin level compared both with controls and SCA subjects in steady state (22.6 ± 13.0 vs. 11.3 ± 5.7 pmol/L, 22.6 ± 13.0 vs. 12.4 ± 5.8 pmol/L, p = 0.009 for both). Additionally, the copeptin level was significantly higher in SCA patients with RV dysfunction than those without RV dysfunction (23.2 ± 12.2 vs. 15.3 ± 9.5 pmol/L, p = 0.024). Multiple logistic regression analysis revealed that high-sensitivity C-reactive protein and copeptin levels were found to be associated with VOC.ConclusionThis study showed that copeptin and hs-CRP levels were increased in patients with VOC, and it was found that RV dysfunction was more common in SCA patients with VOC than in the control group. Copeptin can be considered for use as a potential biomarker in predicting VOC crisis in SCA patients and in the early detection of patients with SCA who have the potential to develop RV dysfunction.  相似文献   
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BackgroundThe coexistence of hyponatremia and atrial fibrillation (AF) increases morbidity and mortality in patients with heart failure (HF). However, it is not established whether hyponatremia is related to AF or not.ObjectiveOur study aims to seek a potential association of hyponatremia with AF in patients with reduced ejection fraction heart failure (HFrEF).MethodsThis observational cross-sectional single-center study included 280 consecutive outpatients diagnosed with HFrEF with 40% or less. Based on sodium concentrations ≤135 mEq/L or higher, the patients were classified into hyponatremia (n=66) and normonatremia (n=214). A p-value <0.05 was considered significant.ResultsMean age was 67.6±10.5 years, 202 of them (72.2%) were male, mean blood sodium level was 138±3.6 mEq/L, and mean ejection fraction was 30±4%. Of those, 195 (69.6%) patients were diagnosed with coronary artery disease. AF was detected in 124 (44.3%) patients. AF rate was higher in patients with hyponatremia compared to those with normonatremia (n=39 [59.1%] vs. n=85 [39.7%), p= 0.020). In the logistic regression analysis, hyponatremia was not related to AF (OR=1.022, 95% CI=0.785–1.330, p=0.871). Advanced age (OR=1.046, 95% CI=1.016–1.177, p=0.003), presence of CAD (OR=2.058, 95% CI=1.122–3.777, p=0.020), resting heart rate (OR=1.041, 95% CI=1.023–1.060, p<0.001), and left atrium diameter (OR=1.049, 95% CI=1.011–1.616, p=0.002) were found to be predictors of AF.ConclusionAF was higher in outpatients with HFrEF and hyponatremia. However, there is no association between sodium levels and AF in patients with HFrEF.  相似文献   
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Plants use light for photosynthesis and for various signaling purposes. The UV wavelengths in sunlight also introduce DNA damage in the form of cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] that must be repaired for the survival of the plant. Genome sequencing has revealed the presence of genes for both CPD and (6-4)PP photolyases, as well as genes for nucleotide excision repair in plants, such as Arabidopsis and rice. Plant photolyases have been purified, characterized, and have been shown to play an important role in plant survival. In contrast, even though nucleotide excision repair gene homologs have been found in plants, the mechanism of nucleotide excision repair has not been investigated. Here we used the in vivo excision repair assay developed in our laboratory to demonstrate that Arabidopsis removes CPDs and (6-4)PPs by a dual-incision mechanism that is essentially identical to the mechanism of dual incisions in humans and other eukaryotes, in which oligonucleotides with a mean length of 26–27 nucleotides are removed by incising ∼20 phosphodiester bonds 5′ and 5 phosphodiester bonds 3′ to the photoproduct.Plants and other organisms that depend on photosynthesis are, by necessity, exposed to more sunlight than other organisms that are chemotrophs or heterotrophs. Hence, plants are expected to receive more exposure to UV wavelengths of light than other organisms. The genotoxic effects of UV are somewhat mitigated by the reflection of UV by the waxy leaf surface and absorbance of UV by the intracellular pigments that are present at high concentration in plant cells, including carotenoids and flavonoids. Nevertheless, plants still receive considerable amounts of DNA-damaging UV radiation and therefore must have the means to cope with the damage to ensure their survival. Indeed, DNA sequencing has revealed that plant genomes contain genes that are homologous to the genes of all major DNA repair pathways, including photoreactivation, nucleotide excision repair, base excision repair, and recombination/double-strand break repair (16).However, biochemical studies of these DNA repair mechanisms have been limited. Of significance, Arabidopsis photolyases have been expressed in heterologous systems, purified, and characterized (79). Similarly, some of the enzymes of the base excision repair and recombination/double-strand break repair systems have been studied. In contrast, there have been no mechanistic studies on plant nucleotide excision repair, although it is known that plants can remove cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] in a photolyase-independent manner (6, 10, 11), presumably by nucleotide excision repair. Here, we have used an Arabidopsis cell line and the in vivo excision assay recently developed in our laboratory (1214) to demonstrate that Arabidopsis removes these photoproducts by dual incisions in a manner that is virtually identical to human nucleotide excision repair.  相似文献   
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Bilateral elastofibroma dorsi   总被引:1,自引:0,他引:1  
Elastofibroma dorsi was diagnosed in a 48-year-old woman with bilateral subscapular tumor masses diagnosed asynchronously in an interval of 4 months in spite of presence of another lesion at first admittance. She underwent subsequent resections of the lesions. They were diagnosed as elastofibroma. Reevaluation of the initial computerized tomography of thorax indicated an omitted small lesion with a 2-cm diameter and 25.2-day doubling time. Although the real neoplastic nature of elastofibroma is unknown, bilateral presence of the masses with different sizes and relatively short doubling times of the lesions must be kept in mind.  相似文献   
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