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21.
Background: The aim of this study is to evaluate the association between heart rate turbulence (HRT) parameters and clinical characteristics of coronary artery disease (CAD) patients. Methods and Results: In 122 patients (mean age 62 ± 9 years) with angiographically documented CAD, 24‐hour Holter monitoring with HRT analysis was performed to evaluate turbulence onset (TO) and turbulence slope (TS). There was a significant correlation between TO and TS (P =?0.31; P < 0.001) . According to quartile values, TO ≥?0.37% and TS ≤ 4.25 ms/RR were considered as abnormal in this patient population. Average values of TO were higher and TS lower in patients over 60 years, in patients with a past history of myocardial infarction and in those with EF < 40%. Considering pharmacotheraphy, higher (better) values of TS were observed in patients on statins, nitrates, and beta‐blockers while lower TS values were noted in patients on calcium blockers. Patients with abnormal parameters of HRT compared to group with normal HRT values were characterized by features of more advanced CAD: age over 60 years (75% vs 49%), past history of MI (75% vs 64%), and EF < 40% (25% vs 3%). Multivariate analysis revealed age > 60 years (OR 1.27; P = 0.002) and EF < 40% (OR 1.39; P = 0.001) as independent clinical factors associated with abnormal HRT parameters. Conclusions: HRT parameters are influenced by clinical characteristics and pharmacotherapy of studied patients with TS more than abnormal TO depending on clinical characteristics of patients. Advanced age, prior myocardial infarction and left ventricular dysfunction are key factors influencing values of HRT parameters.  相似文献   
22.

Objectives

The aim of the analysis is to determine dynamic changes in somatostatin (SS) and interleukin-6 (IL-6) concentrations during in acute pancreatitis (AP).

Methods

The influence of tobacco smoking on IL-6 and SS levels in the serum of non-smoking (n?=?10) and smoking (n?=?27) patients with diagnosed AP and control group: non-smoking (n?=?44), smoking (n?=?42) and passive smoking (n?=?29) healthy persons was proved. The concentration of IL-6 and SS was determined by means of ELISA. Differences between the groups analyzed were tested using the U Mann Whitney test. The Spearman rank correlation analysis was used to evaluate the correlations.

Results

The concentrations of IL-6 and SS were significantly higher in smoking patients with AP and healthy persons when compared with non-smoking population on every day (1 day: p?=?0.0002, p?=?0.015; 3 day: p?=?0.005, p?=?0.001 and 7 day: p?=?0.025, p?=?0.038). Dynamic changes in concentrations of IL-6 and SS in the serum of patients with AP were demonstrated in the ensuing days of the disease. In case of non-smoking and smoking patients, significant positive correlations between IL-6 and SS was observed.

Conclusions

These findings suggest that some of the antiinflammatory effects of SS against acute pancreatitis may be mediated by reducing the local proinflammatory cytokine secretion in the pancreas.  相似文献   
23.
Earlier studies have demonstrated that human platelets contain the 20S proteasome, and its protein activator. However, understanding the potential role of the proteasome in human platelets requires a detailed knowledge about its chymotryptic-like activity, a crucial one for protein degradation in all eukaryotic cells. In this communication we have shown that human platelet 20S proteasome exhibited chymotryptic-like activity towards succinyl-Leu-Leu-Val-Tyr-7-amido-4-methylcoumarin as substrate at a broad pH range, with optimum between pH 7.5-8.0 and 5.0-5.5. These two activities were markedly inhibited by a 10 micromol/l concentration of two structurally unrelated proteasome inhibitors: lactacystin/beta-lactone or benzyloxycarbonyl-Ile-Glu(O-tert.-butyl)-Ala-leucinal, but not by ebelactone B, an inhibitor of lysosomal cathepsin A/deamidase. The chymotryptic-like activity of the 20S proteasome against succinyl-Leu-Leu-Val-Tyr-7-amido-4-methylcoumarin was also significantly inhibited in platelets, after exposure of platelet-rich plasma to 10 micromol/l lactacystin and benzyloxycarbonyl-Ile-Glu(O-tert.-butyl)-Ala-leucinal for up to 60 min. This indicates that these inhibitors can enter platelets and selectively inhibit 20S proteasome activity. We also demonstrated for the first time by Western blot analysis that human platelets contain a proteasome activator, PA28, which is known to play a key role in antigen processing by significant stimulation of the proteasomal chymotryptic-like activity. Since the platelet 20S proteasome was also present in a latent form, this suggests that its activity may be regulated in vivo in human platelets. All these results can therefore be beneficial in future studies on the role of the 20S proteasome in platelet biology.  相似文献   
24.
25.

Introduction

Ischemia/reperfusion (I/R) is considered to be one of the main causes of liver damage after transplantation. The authors evaluated the effect of ezetimibe on selected oxidative stress parameters in ischemic/reperfused (I/R) rat liver.

Material and methods

Rats were administered ezetimibe (5 mg/kg) (groups E and E-I/R) or saline solution (groups C and C-I/R) intragastrically for 21 days. Livers of animals in groups C-I/R and E-I/R were subjected to 60 min of partial ischemia (left lateral and median lobes) followed by 4 h of reperfusion. Alanine and asparagine aminotransferase (ALT, AST) activity was determined in blood before I/R and during reperfusion (at 15 and 240 min). After the reperfusion period, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx) were determined in liver homogenates using colorimetric methods.

Results

Ezetimibe caused a significant increase in GSH level in groups subjected to I/R (E-I/R (99.91 ±9.01) vs. C-I/R (90.51 ±8.87), p < 0.05). Additionally, under I/R the decrease of GPx activity in the drug-treated group was lower compared to the non-treated group (E-I/R (3.88 ±1.11) vs. E (5.31 ±1.83), p = 0.076). Neither ezetimibe nor I/R affected SOD or MDA levels. I/R produced a significant increase in aminotransferase levels (ALT240-0: C-I/R (42.23 ±43.56) vs. C (9.75 ±11.09), and E-I/R (39.85 ±26.53) vs. E (4.38 ±1.36), p < 0.05 in both cases; AST 240-0: E-I/R (53.87 ±17.23) vs. E (24.10 ±9.66), p < 0.05) but no effect of ezetimibe on those enzymes was found.

Conclusions

Ezetimibe demonstrates antioxidant properties in rat livers subjected to I/R. However, neither a hepatoprotective nor a hepatotoxic effect of ezetimibe was demonstrated, regardless of I/R.  相似文献   
26.
Mutations in cystic fibrosis transductance regulator gene (CFTR) are known to result in some forms of male infertility. An association between CFTR gene mutations and obstructive azoospermia in cystic fibrosis (CF) and in congenital unilateral and bilateral absence of vas deferens (CUAVD, CBAVD) has been proven. However, the role of CFTR gene mutations in the etiology of non-obstructive azoospermia, as well as in the regulation of spermatogenesis remains unsolved. OBJECTIVES: The aim of the study was to evaluate the frequency of CFTR mutations in patients diagnosed with different forms of spermatogenesis impairment MATERIAL: The molecular analyses were performed in the group of 93 infertile men, diagnosed with either azoospermia, oligospermia or asthenoteratozoospermia. RESULTS: The results of the study revealed the presence of F508del and IVS8-T in 5.4% of analyzed cases. No difference in CFTR gene mutations frequencies among patients with azoospermia, oligospermia and asthenoteratozoospermia has been observed. CONCLUSION: The CFTR gene mutations frequency in men with nonobstructive azoospermia, oligozoospermia and asthenozoospermia is similar to those observed in general population.  相似文献   
27.

Background

Monocyte-platelet interaction may favor the development of a proatherogenic monocyte phenotype. It is still uncertain which of the 3 monocyte subpopulations interact with platelets to form monocyte-platelet aggregates (MPAs) in acute myocardial infarctions. The aim of our study was to evaluate the monocyte subsets, the percentage of MPAs and the involvement of monocyte subsets in MPA formation among patients with ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI), and compared to patients with stable angina (SA).

Methods

Monocyte subsets and MPAs formation were measured in blood collected in 3.2% sodium citrate tubes by means of flow cytometry.

Results

Classical, intermediate and nonclassical monocyte percentages were statistically different when comparing patients with STEMI and NSTEMI. Moreover, classical and intermediate monocytes were statistically different when comparing the STEMI and SA group; however, only the classical monocyte subset was found to be higher in the acute myocardial infarction group compared to the SA group. The percentage of MPAs was significantly higher in STEMI (50.1%) compared to NSTEMI (22.9%). We found no differences in the involvement of monocyte subsets in MPA formation between patients with STEMI and NSTEMI and in comparison with the SA group.

Conclusions

These findings suggest that the increase in circulating levels of classical monocytes in patients with STEMI as compared to NSTEMI reflects the severity of the acute event. The increased percentage of MPAs may favor the development of STEMI compared to NSTEMI.  相似文献   
28.
Inorganic aluminum or iron salts supported with synthetic polymers are commonly used to eradicate colloidal particles from water in coagulation and flocculation processes. Nevertheless, these agents have several disadvantages, such as large volumes of sludge produced or environmental toxicity. Recently biodegradable polymers have been suggested as eco-friendly flocculants for water treatment. This study aimed to investigate the possibilities of using starch and chitosan and their oxidized derivatives as flocculants for filter backwash water treatment. Dialdehyde starch (DST) and dialdehyde chitosan (DCT) were synthesized by periodate oxidization of natural starch from corn and low molecular weight chitosan. The obtained materials have been characterized with scanning electron microscopy (SEM), ATR-FTIR spectroscopy, and thermogravimetric analysis (TGA). Furthermore, we studied the flocculation properties of polysaccharide flocculants in a series of jar tests. The effectiveness of chitosan and starched-based flocculants was compared to synthetic polymers commonly used to treat iron ions-rich filter backwash water. The environmental aspects of these chemicals, particularly the biodegradability of post-flocculation residues, were also addressed. It was found that oxidized starch and chitosan derivatives can be used as ecological flocculating materials to treat potable water or sludge.  相似文献   
29.
The analysis of single nucleotide polymorphisms (SNPs) is increasingly utilized to investigate the genetic causes of complex human diseases. Here we present a high-throughput genotyping platform that uses a one-primer assay to genotype over 10,000 SNPs per individual on a single oligonucleotide array. This approach uses restriction digestion to fractionate the genome, followed by amplification of a specific fractionated subset of the genome. The resulting reduction in genome complexity enables allele-specific hybridization to the array. The selection of SNPs was primarily determined by computer-predicted lengths of restriction fragments containing the SNPs, and was further driven by strict empirical measurements of accuracy, reproducibility, and average call rate, which we estimate to be >99.5%, >99.9%, and>95%, respectively [corrected]. With average heterozygosity of 0.38 and genome scan resolution of 0.31 cM, the SNP array is a viable alternative to panels of microsatellites (STRs). As a demonstration of the utility of the genotyping platform in whole-genome scans, we have replicated and refined a linkage region on chromosome 2p for chronic mucocutaneous candidiasis and thyroid disease, previously identified using a panel of microsatellite (STR) markers.  相似文献   
30.
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