The Protective Effect of Na+/Ca2+ Exchange Blocker KB-R7943 on Myocardial Ischemia–Reperfusion Injury in Hypercholesterolemic Rat

KB-R7943 reduces lethal reperfusion injury under normal conditions, but its effectiveness under certain pathological states is in dispute. In the present study, we sought to determine the effect of KB-R7943 in hyperlipidemic animals and assess if the K _ATP ⁺ are involved in the protective mechanisms. In group 1 (G1), isolated rat hearts underwent 25 min global ischemia (GI) and 120 min reperfusion (R). In group 2 (G2), G1 was repeated but the animals were subjected to a 1.5 % cholesterol-enriched diet during 6 weeks (hypercholesterolemic animals). In group 3 (G3), G2 was repeated but 1 μM KB-R7943 was added to the perfusate for 10 min from the start of reperfusion. In group 4 (G4), G3 was repeated, and glibenclamide (K _ATP ⁺ , blocker, 0.3 μM) was administered. The infarct size was measured by triphenyltetrazolium. The infarct size was 35 ± 5.0 % in G1 and 46 ± 8.7 % in G2 (P < 0.05); KB-R7943 reduced the infarct size (28.6 ± 3.3 % in G3 vs. G2, P < 0.05). In addition, KB-R7943 attenuated apoptotic cell (G3 vs. G2, P < 0.05), but glibenclamide abolished the effect reached by KB-R7943. Thus, diet-induced hypercholesterolemia enhances myocardial injury; KB-R7943 reduces infarct size and apoptosis in hyperlipidemic animals through the activation of K⁺ATP channels.     

Protective Effect of Na+/Ca2+ Exchange Blocker KB-R7943 on Myocardial Ischemia–Reperfusion Injury in Hypercholesterolemic Rats

Reverse-mode activation of the Na⁺/Ca²⁺ exchanger (NCX) during reperfusion following ischemia contributes to Ca²⁺ overload and cardiomyocyte injury. KB-R7943, a selective reverse-mode NCX inhibitor, reduces lethal reperfusion injury under non-ischemic conditions. However, the effectiveness of this compound under ischemic conditions is unclear. In the present study, we studied the effects of KB-R7943 in an animal model of hyperlipidemia. We further assessed whether the K _ATP ⁺ channels are involved in potential protective mechanisms of KB-R7943. Twelve rats were fed normal chow, while 48 animals were fed a high cholesterol diet. The hearts from the control and hypercholesterolemic rats were subjected to 25 min of global ischemia followed by a 120-min reperfusion. Before this, hearts from hypercholesterolemic rats either received no intervention (cholesterol control group) or were pre-treated with 1 μM KB-R7943 and 0.3 μM of K _ATP ⁺ blocker glibenclamide or glibenclamide alone. The infarction sizes (triphenyltetrazolium assay) were 35 ± 5.0 % in the control group, 46 ± 8.7 % in the cholesterol control group (p < 0.05 vs. control group), 28.6 ± 3.3 % in the KB-R7943 group (p < 0.05 vs. cholesterol control group), 44 ± 5 % in the KB-R7943 and glibenclamide group, and 47 ± 8.5 % in the glibenclamide group (p < 0.05 vs. control group). Further, KB-R7943 attenuated the magnitude of cell apoptosis (p < 0.05 vs. cholesterol control group). These beneficial effects were abolished by glibenclamide. In conclusion, diet-induced hypercholesterolemia enhances myocardial injury. Selective reverse-mode NCX inhibitor KB-R7943 reduces the infarction size and apoptosis in hyperlipidemic animals through the activation of K _ATP ⁺ channels.     

Differing cardioprotective efficacy of the Na+/Ca2+ exchanger inhibitors SEA0400 and KB-R7943

KB-R7943 and SEA0400 are Na(+)/Ca(2+) exchanger (NCX) inhibitors with differing potency and selectivity. The cardioprotective efficacy of these NCX inhibitors was examined in isolated rabbit hearts (Langendorff perfused) subjected to regional ischemia (coronary artery ligation) and reperfusion. KB-R7943 and SEA0400 elicited concentration-dependent reductions in infarct size (SEA0400 EC(50): 5.7 nM). SEA0400 was more efficacious than KB-R7943 (reduction in infarct size at 1 microM: SEA0400, 75%; KB-R7943, 40%). Treatment with either inhibitor yielded similar reductions in infarct size whether administered before or after regional ischemia. SEA0400 (1 microM) improved postischemic recovery of function (+/-dP/dt), whereas KB-R7943 impaired cardiac function at >/=1 microM. At 5-20 microM, KBR-7943 elicited rapid and profound depressions of heart rate, left ventricular developed pressure, and +/-dP/dt. Thus the ability of KB-R7943 to provide cardioprotection is modest and limited by negative effects on cardiac function, whereas the more selective NCX inhibitor SEA0400 elicits marked reductions in myocardial ischemic injury and improved +/-dP/dt. NCX inhibition represents an attractive approach for achieving clinical cardioprotection.     

The Protective Effect of Mitochondrial ATP-Sensitive K<Superscript>+</Superscript> Channel Opener,Nicorandil, Combined With Na<Superscript>+</Superscript>/Ca<Superscript>2+</Superscript> Exchange Blocker KB-R7943 on Myocardial Ischemia–Reperfusion Injury in Rat

To study the protective effect of mitochondrial ATP-sensitive K⁺ channel (mitoK_ATP channel) opener, nicorandil, combined with Na⁺/Ca²⁺ exchange blocker KB-R7943 on myocardial ischemia–reperfusion injury in isolated rat hearts; the isolated rat heart was perfused by modified Langendorff device, after 15-min balanced perfusion, 45-min ischemia (about left and right coronary perfusion flow reduced to 5% of the original irrigation flow), and 2-h reperfusion were performed. Forty Wistar rats were randomly divided into four groups: control group, nicorandil group, KB-R7943 group, and the combination of nicorandil and KB-R7943 group. After 45-min ischemia and then 2-h reperfusion, the myocardial infarct size was 34.31% in control group, 26.35% in nicorandil group, 28.74% in KB-R7943 group, and 19.23% in combination of nicorandil and KB-R7943 group. SOD activity in coronary perfusion fluid was the highest in the combination of nicorandil and KB-R7943 group, and MDA content was the lowest. In the combination drug group compared with the control group, myocardial ultrastructural injury was significantly reduced. The combination of nicorandil and KB-R7943 significantly reduced myocardial infarct size, significantly reduced myocardial ultrastructural damage, could increase coronary perfusion fluid SOD activity, and reduced MDA levels.     

The effects of KB-R7943, an inhibitor of reverse Na<Superscript>+</Superscript>/Ca<Superscript>2+</Superscript> exchange,on the force of contraction of papillary muscles in the heart of the ground squirrel <Emphasis Type="Italic">Spermophilus undulatus</Emphasis>

We investigated the effect of KB-R7943, an inhibitor of the reverse mode of Na⁺/Ca²⁺ exchanger, on the force of isometric contractions, the contractile force–frequency relationship and post-rest potentiation (a qualitative parameter of Ca²⁺ levels in sarcoplasmic reticulum) in the right ventricle papillary muscles isolated from ground squirrel hearts during summer (June, n = 4) and autumn (October, n = 4) activities. In the presence of 1.8 mM Ca2+at 36°C, 1–1.5 hours-long treatment of the summer papillary muscles with KB-R7943 produced no significant effects on the contractile indices at the majority of stimulation frequencies. In the autumn papillary muscles KB-R7943 induced a 40–50% decrease in the force of contraction (negative inotropic effect) at low stimulation frequencies (0.1–0.3 Hz) without any significant effect at higher stimulation frequencies (0.4–3.0 Hz). Furthermore, in this group, KB-R7943 suppressed the post-rest potentiation of contractility by 50 ± 21% at pause durations exceeding 120 s. These observations indicate that KB-R7943 can affect Ca²⁺ levels in sarcoplasmic reticulum and that Na⁺/Ca2⁺ exchange may contribute to the physiological remodeling of intracellular Ca²⁺ homeostasis in myocardium of hibernating animals prior their transition to a hypometabolic torpid state.     

Serum Trace Element Levels in Febrile Convulsion

Febrile convulsion is the most common disorder in childhood with good prognosis. There are different hypotheses about neurotransmitters and trace element changes in biological fluids which can have a role in pathogenesis of febrile convulsion. In this study, serum selenium, zinc, and copper were measured by atomic absorption spectrometry in the children with febrile convulsion (n?=?30) and in the control group (n?=?30). The age and sex of the subjects were registered. Selenium and zinc were found to be significantly lower in febrile convulsion cases than in the control group (p?<?0.0001 and p?<?0.0001, respectively). There was no significant difference in the value of copper between the two groups (p?=?0.16). While selenium and zinc levels were 44.92?±?10.93 μg/l and 66.13?±?18.97 μg/dl in febrile convulsion, they were found to be 62.98?±?9.80 μg/l and 107.87?±?28.79 μg/dl in healthy children. Meanwhile, copper levels were 146.40?±?23.51 μg/dl in the patients and 137.63?±?24.19 μg/dl in the control group, respectively. This study shows that selenium and zinc play an important role in the pathogenesis of febrile convulsion.     

The Influences of Chromium Supplementation on Glycemic Control,Markers of Cardio-Metabolic Risk,and Oxidative Stress in Infertile Polycystic ovary Syndrome Women Candidate for In vitro Fertilization: a Randomized,Double-Blind,Placebo-Controlled Trial

This study was carried out to investigate the effects of chromium intake on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome (PCOS) women candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was done among 40 subjects with infertile PCOS candidate for IVF, aged 18–40 years old. Individuals were randomly allocated into two groups to take either 200 μg/day of chromium (n?=?20) or placebo (n?=?20) for 8 weeks. Biochemical parameters were assessed at baseline and at end-of-trial. Compared with the placebo, taking chromium supplements led to significant reductions in fasting plasma glucose (??2.3?±?5.7 vs. +?0.9?±?3.1 mg/dL, P?=?0.03), insulin levels (??1.4?±?2.1 vs. +?0.4?±?1.7 μIU/mL, P?=?0.004), homeostatic model of assessment for insulin resistance (??0.3?±?0.5 vs. +?0.1?±?0.4, P?=?0.005), and a significant increase in quantitative insulin sensitivity check index (+?0.004?±?0.008 vs. ??0.001?±?0.008, P?=?0.03). In addition, chromium supplementation significantly decreased serum triglycerides (??19.2?±?33.8 vs. +?8.3?±?21.7 mg/dL, P?=?0.004), VLDL- (??3.8?±?6.8 vs. +?1.7?±?4.3 mg/dL, P?=?0.004) and total cholesterol concentrations (??15.3?±?26.2 vs. ??0.6?±?15.9 mg/dL, P?=?0.03) compared with the placebo. Additionally, taking chromium supplements was associated with a significant increase in plasma total antioxidant capacity (+?153.9?±?46.1 vs. ??7.8?±?43.9 mmol/L, P?<?0.001) and a significant reduction in malondialdehyde values (?0.3?±?0.3 vs. +?0.1?±?0.2 μmol/L, P?=?0.001) compared with the placebo. Overall, our study supported that chromium administration for 8 weeks to infertile PCOS women candidate for IVF had beneficial impacts on glycemic control, few variables of cardio-metabolic risk, and oxidative stress.     

A New Species of Rhaponticoides (Asteraceae) from Southern Italy

A new diploid (2n?=?30) species, Rhaponticoides calabrica, is described from Calabria and Basilicata (southern Italy). This species differs from the closely related R. centaurium – an endemic of Apulia and northern Basilicata – by different flower colour (white in the former, purplish in the latter), width of membranous margin of phyllaries (1.8?±?0.4 mm vs 0.8?±?0.3 mm) and pappus length (6.8?±?0.9 mm vs 9.1?±?1.0 mm). The two species are completely allopatric and seem to have also different chromosome numbers.     

Inhibition of Na+/Ca2+ exchange by KB-R7943: transport mode selectivity and antiarrhythmic consequences

The Na+/Ca2+ exchanger plays a prominent role in regulating intracellular Ca2+ levels in cardiac myocytes and can serve as both a Ca2+ influx and efflux pathway. A novel inhibitor, KB-R7943, has been reported to selectively inhibit the reverse mode (i.e., Ca2+ entry) of Na+/Ca2+ exchange transport, although many aspects of its inhibitory properties remain controversial. We evaluated the inhibitory effects of KB-R7943 on Na+/Ca2+ exchange currents using the giant excised patch-clamp technique. Membrane patches were obtained from Xenopus laevis oocytes expressing the cloned cardiac Na+/Ca2+ exchanger NCX1.1, and outward, inward, and combined inward-outward currents were studied. KB-R7943 preferentially inhibited outward (i.e., reverse) Na+/Ca2+ exchange currents. The inhibitory mechanism consists of direct effects on the transport machinery of the exchanger, with additional influences on ionic regulatory properties. Competitive interactions between KB-R7943 and the transported ions were not observed. The antiarrhythmic effects of KB-R7943 were then evaluated in an ischemia-reperfusion model of cardiac injury in Langendorff-perfused whole rabbit hearts using electrocardiography and measurements of left ventricular pressure. When 3 microM KB-R7943 was applied for 10 min before a 30-min global ischemic period, ventricular arrhythmias (tachycardia and fibrillation) associated with both ischemia and reperfusion were almost completely suppressed. The observed electrophysiological profile of KB-R7943 and its protective effects on ischemia-reperfusion-induced ventricular arrhythmias support the notion of a prominent role of Ca2+ entry via reverse Na+/Ca2+ exchange in this process.     

Monoamine oxidase-induced hydroxyl radical production and cardiomyocyte injury during myocardial ischemia–reperfusion in rats

To elucidate the involvement of monoamine oxidase (MAO) in hydroxyl radical production and cardiomyocyte injury during ischemia as well as after reperfusion, we applied microdialysis technique to the heart of anesthetized rats. Dialysate samples were collected during 30?min of induced ischemia followed by 60?min of reperfusion. We monitored dialysate 3,4-dihydrobenzoic acid (3,4-DHBA) concentration as an index of hydroxyl radical production using a trapping agent (4-hydroxybenzoic acid), and dialysate myoglobin concentration as an index of cardiomyocyte injury in the ischemic region. The effect of local administration of a MAO inhibitor, pargyline, was investigated. Dialysate 3,4-DHBA concentration increased from 1.9?±?0.5?nM at baseline to 3.5?±?0.7?nM at 20–30?min of occlusion. After reperfusion, dialysate 3,4-DHBA concentration further increased reaching a maximum (4.5?±?0.3?nM) at 20–30?min after reperfusion, and stabilized thereafter. Pargyline suppressed the averaged increase in dialysate 3,4-DHBA concentration by ～72% during occlusion and by ～67% during reperfusion. Dialysate myoglobin concentration increased from 235?±?60?ng/ml at baseline to 1309?±?298?ng/ml at 20–30?min after occlusion. After reperfusion, dialysate myoglobin concentration further increased reaching a peak (5833?±?1017?ng/ml) at 10–20?min after reperfusion, and then declined. Pargyline reduced the averaged dialysate myoglobin concentration by ～56% during occlusion and by ～41% during reperfusion. MAO plays a significant role in hydroxyl radical production and cardiomyocyte injury during ischemia as well as after reperfusion.     

Hemodialysis Decreases Serum Brain-Derived Neurotrophic Factor Concentration in Humans

In the present study we have evaluated the effect of a single hemodialysis session on the brain-derived neurotrophic factor levels in plasma [BDNF]_pl and in serum [BDNF]_s as well as on the plasma isoprostanes concentration [F₂ isoprostanes]_pl, plasma total antioxidant capacity (TAC) and plasma cortisol levels in chronic kidney disease patients. Twenty male patients (age 69.8?±?2.9?years (mean?±?SE)) with end-stage renal disease undergoing maintenance hemodialysis on regular dialysis treatment for 15?C71?months participated in this study. A single hemodialysis session, lasting 4.2?±?0.1?h, resulted in a decrease (P?=?0.014) in [BDNF]_s by ~42?% (2,574?±?322 vs. 1,492?±?327?pg?ml^?1). This was accompanied by an increase (P?<?10^?4) of [F₂-Isoprostanes]_pl (38?±?3 vs. 116?±?16?pg?ml^?1), decrease (P?<?10^?4) in TAC (1,483?±?41 vs. 983?±?35 trolox equivalents, ??mol?l^?1) and a decrease (P?=?0.004) in plasma cortisol level (449.5?±?101.2 vs. 315.3?±?196.3?nmol?l^?1). No changes (P?>?0.05) in [BDNF]_pl and the platelets count were observed after a single dialysis session. Furthermore, basal [BDNF]_s in the chronic kidney disease patients was significantly lower (P?=?0.03) when compared to the age-matched control group (n?=?23). We have concluded that the observed decrease in serum BDNF level after hemodialysis accompanied by elevated [F₂-Isoprostanes]_pl and decreased plasma TAC might be caused by enhanced oxidative stress induced by hemodialysis.     

Diosgenin attenuates inflammatory response induced by myocardial reperfusion injury: role of mitochondrial ATP-sensitive potassium channels

Reperfusion injury is one of the main reasons of cardiac disease morbidity. Phytopharmaceuticals are gaining importance in modern medicine of cardioprotection because of their multiplex capacity. The aim of this study was to investigate the effect of diosgenin on the inflammatory response induced by myocardial ischemia and reperfusion injury and the role of mitochondrial ATP-sensitive potassium (mitoKATP) channels in this regard. Wistar rats (250–300 g) were used in this study. The Langendorff-perfused hearts of animals were subjected to a 30-min global ischemia followed by a 90-min reperfusion. The lactate dehydrogenase (LDH) release was measured by spectrophotometry. The levels of inflammatory mediators tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and IL-6 in the supernatant of heart’s left ventricle were measured using an enzyme-linked immunosorbent assay rat specific ELISA kit. The LDH release into the coronary effluent during reperfusion was significantly decreased, and cardiac contractility significantly improved by diosgenin preadministration as compared with those of control or Cremophor-EL (solvent of diosgenin) groups (398?±?48 vs. 665?±?65 or 650?±?73 ml/min) (P?<?0.01). Administration of diosgenin before the main ischemia significantly reduced the levels of IL-6 (P?<?0.05), IL-1β, and TNF-α (P?<?0.01) in the reperfusion phase of diosgenin-treated hearts as compared with untreated control hearts. Inhibition of mitoKATP channels by 5-hydroxydecanoate significantly reverses the cardioprotective effects of diosgenin (P?<?0.05). The findings of the present study indicate that preconditioning with diosgenin may induce cardioprotective effect against reperfusion injury through reducing the production of inflammatory mediators and activating the mitoKATP channels.     

Ovariectomy Reinstates the Infarct Size-Limiting Effect of Postconditioning in Female Rabbits

Gender seems to interfere with the cardioprotective effect of ischemic preconditioning (PreC) and postconditioning (PostC); PreC-conferred protection is weaker or lost in female animals after ovariectomy (Ov), while the role of PostC is still in dispute. We sought to investigate the effect of PostC in female rabbits, its interaction with Ov, and the potential implicated intracellular pathways. Intact or Ov adult female rabbits (n = 46) were subjected to 30 min ischemia and reperfusion with PostC (PostC or OvPostC), which consisted of six cycles of 30-s ischemia/30-s reperfusion at the end of ischemia, or without PostC (Fem or OvFem). Infarct size (I) and area at risk (R) were determined by TTC staining and fluorescent particles, respectively, after 3-h reperfusion in 30 out of 46 animals. Plasma levels of estradiol and nitrite/nitrate (NO _x ) were evaluated. ERKs, p38-MAPK, and Akt assessment was performed in excised hearts 1-min after starting the final reperfusion period in the remaining 16 animals. Infarct size was significantly reduced only in OvPostC group (I/R ratio, 25.3 ± 2.7, vs 48.1 ± 2.0, 43.6 ± 4.2 and 55.1 ± 5.6 % in Fem, OvFem, and PostC groups, p < 0.05). In ovariectomized rabbits, plasma estradiol and NO _x levels were lower than in the normal ones. Akt phosphorylation in ischemic regions was significantly higher in OvPostC group, whereas ERK1/2 and p38-MAPK activation was observed in all ovariectomized animals irrespective of PostC. PostC is not effective in female rabbits, but the protection is reinstated after Ov potentially via the RISK pathway.     

Right ventricular size and function under riociguat in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (the RIVER study)

Background

Riociguat is a soluble guanylate cyclase stimulator approved for pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTPEH). The objective of this study was to evaluate right heart size and function assessed by echocardiography during long term treatment with riociguat.

Methods

Patients who started riociguat treatment (1.0–2.5?mg tid) within the trials phase II, PATENT, PATENTplus, EAS, CHEST and continued treatment for 3–12?months were included in this study. Echocardiography was analysed off-line at baseline, after 3, 6 and 12?months by investigators who were blinded to clinical data. Last and baseline observation carried forward method (LOCF, BOCF) were performed as sensitivity analysis.

Results

Seventy-one patients (45% PAH, 55% CTEPH; 53.5% female; 60?±?13?years, mean pulmonary arterial pressure 46?±?10?mmHg, mean PVR 700?±?282dynes·sec·cm-5) were included. After 6?months, RA and RV area, RV thickness tricuspid regurgitation velocity showed a significant reduction. After 12?months, patients receiving riociguat therapy showed a significant reduction in right atrial (??2.6?±?4.4?cm2, 95% CI -3.84, ??1.33; p?<?0.001, n?=?49) and right ventricular (RV) area (??3.5?±?5.2?cm2, 95% CI -5.1, ??1.9; p?<?0.001; n?=?44), RV thickness (??0.76?±?2.2?mm, 95% CI -1.55, 0.03; n?=?32), and a significant increase in TAPSE (2.95?±?4.78?mm, 95% CI 1.52, 4.39; n?=?45) and RV fractional area change (8.12?±?8.87?mm, 95% CI 4.61, 11.62; n?=?27).Both LOCF and BOCF showed similar results but lower effect sizes.

Conclusion

Patients under long-term treatment with riociguat show significantly reduced right heart size and improved RV function in PAH and CTEPH. Further controlled prospective studies are needed to confirm these results.

     

Tissue-engineered mesh for pelvic floor reconstruction fabricated from silk fibroin scaffold with adipose-derived mesenchymal stem cells

A tissue-engineered mesh fabricated with adipose-derived mesenchymal stem cells (AD-MSCs) cultured on a silk fibroin scaffold is evaluated for use in female pelvic reconstruction. Thirty-five female Sprague Dawley rats were divided into four groups. Group A (n?=?10) were implanted with polypropylene meshes, Group B (n?=?10) with silk fibroin scaffolds and Group C (n?=?10) with tissue-engineered meshes. Group D (n?=?5) acted as the tissue control. The tissue-engineered mesh was produced as follows. AD-MSCs were obtained from adipose tissue of rats designated to Group C. The cells were seeded onto a silk fibroin scaffold, cultured and then observed by scanning electron microscopy (SEM). Histological studies of these meshes were performed at 4 and 12 weeks after implantation and mechanical testing was carried out on all groups before implantation and at 12 weeks after implantation. AD-MSCs displayed fibroblast-like shapes and were able to differentiate into adipocytes or fibroblasts. SEM observation showed that AD-MSCs proliferated and secreted a matrix onto the silk fibroin scaffolds. After implantation of the scaffolds into rats, histological analysis revealed better organized newly formed tissue in Group C than in controls. Group C also had a similar failure force (2.67?±?0.15 vs 2.33?±?0.38 N) and a higher Young’s modulus (2.99?±?0.19 vs 1.68?±?0.20 MPa) than a normal vaginal wall, indicating the potential of this tissue-engineered approach. AD-MSCs were validated as seed cells for tissue engineering. The silk fibroin scaffold thus shows promise for application with AD-MSCs in the fabrication of tissue-engineered mesh with good biocompatibility and appropriate mechanical properties for pelvic floor reconstruction.     

Determining immunoassay cutoff value using Western blot results to predict hepatitis C infection in blood donors with low-titer anti-HCV reactivity

Since the 1990s, blood donors have been scanned for anti-hepatitis C virus (anti-HCV) antibodies, which can be defined by enzyme immunoassay as a screening test. In this population, false-reactive ratios have been high. Recently, some authors have aimed to find a cutoff value for anti-HCV different from those established by test manufacturers to predict HCV infection. In this study, 321 patients, after two repeating tests, had reactive results in s/co <10 titers on anti-HCV test. The patients were 29.6 % (n?=?95) in women and 70.4 % (n?=?226) in men. The patients were classified into three groups by Western blot (WB) results (PS, positive; NG, negative; and ID, indeterminate). The average anti-HCV titer of the whole group was 2.61?±?1.96. Anti-HCV titers of subgroups were 2.43?±?1.95 in NG, 4.93?±?2.53 in PS, and 2.50?±?1.65 in ID (p?<?0.001). There was a significant difference between NG and PS and between PS and ID subgroups (p?<?0.001). There was a positive correlation between WB and anti-HCV titers in all patients (r?=?0.298, p?<?0.001), in women (r?=?0.282, p?<?0.001), and in men (r?=?0.337, p?=?0.002). According to receiver operator characteristic curve analysis, the cutoff value of anti-HCV titer to predict hepatitis C infection was >2.61 s/co, with 74.1 % sensitivity and 71.6 % specificity (area under the curve, 0.820; 95 % confidence interval, 0.753 to 0.887). We suggest that an effective cutoff value for anti-HCV other than that established by the manufacturer cannot be assigned to predict hepatitis C infection for blood donors in low-prevalence areas.     

Relations of Bromine,Iron, Rubidium,Strontium, and Zinc Content to Morphometric Parameters in Pediatric and Nonhyperplastic Young Adult Prostate Glands

The variation with age of the Br, Fe, Rb, Sr, and Zn mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by an energy-dispersive X-ray fluorescence and a quantitative morphometric analysis. Mean values?±?standard error of the mean (M?±?SΕΜ) for the mass fractions (in milligrams per kilogram wet-mass basis) of these trace elements in pre-puberty were: Br—10.5?±?1.3, Fe—28.6?±?4.1, Rb—3.05?±?0.27, Sr—0.42?±?0.08, and Zn—32.9?±?3.2. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Br—5.60?±?0.57, Fe—19.3?±?1.6, Rb—3.50?±?0.28, Sr—0.24?±?0.03, and Zn—113?±?10. Mean values (M?±?SΕΜ) of percent volumes (%) of the stroma, epithelium, and lumen in the prostate before puberty were 73.4?±?2.6, 20.4?±?1.7, and 4.45?±?0.94, respectively, versus 46.5?±?2.5, 38.5?±?1.9, and 14.9?±?1.2 during puberty and postpuberty. A significant positive correlation between the prostatic Zn and percent volume of both glandular epithelium (r?=?0.573, p?≤?0.001) and glandular lumen (r?=?0.725, p?≤?0.001) was found. For the first time, it has been demonstrated that the glandular lumen is a main pool of Zn accumulation, and that the stroma is a main pool of Br and Fe accumulation in the normal human prostate, for the age range 14 to 30 years. It was concluded that the Zn binds tightly within the prostatic fluid because the volume of glandular lumen reflects the volume of prostatic fluid.     

Distinctive expression and cellular distribution of dopamine receptors in the pancreatic islets of rats

Activation of the dopamine (DA) D2 receptor inhibits glucose-stimulated insulin secretion in isolated rodent islets in vitro; however, no information is available regarding the cellular localization of DA receptors (DRs, including D1-D5 receptors) in pancreatic islets in situ. We investigate the protein expression and cellular localization of five types of DRs in pancreatic islets by means of Western blotting and double-labeling immunofluorescence in both normal control and alloxan-induced type 1 diabetes model (T1DM) rats. In control rats, D1 immunoreactivity (-IR) was distributed in the core of the islet and co-localized with insulin-IR, D2-IR was peripherally distributed and found only in somatostatin-immunoreactive cells and D5-IR was co-localized with glucagon-IR and pancreatic polypeptide-IR. No IR for either the D3 or D4 receptor was observed in rat islets. The protein level of the D1 receptor was reduced in T1DM rats (D1/D-glyceraldehyde-3-phosphate dehydrogenase [GAPDH], 0.63?±?0.05 in control rats compared with 0.16?±?0.03 in T1DM rats, n?=?8, P?n?=?8, P?=?0.42) or the D5 receptor (D5/GAPDH, 0.50?±?0.04 compared with 0.47?±?0.04, n?=?8, P?=?0.58). The present study is the first clear demonstration of the protein expression and cellular localization of the D1, D2 and D5 receptors in rat pancreatic islets and provides crucial morphological evidence for further investigations of the underlying mechanism regarding the DA regulation of pancreatic endocrine function.     

Effect of Fixed Orthodontic Therapy on Urinary Nickel Levels: A Long-term Retrospective Cohort Study

Nickel constitutes about 8?C60?% of orthodontic alloys. It is known as an allergenic/cytotoxic trace metal. Therefore, it should be investigated in patients undergoing orthodontic treatment which might last for 2 or 3?years. However, no controlled studies have assessed the influence of orthodontic treatments of longer than 5?months on its systemic levels. Thus, the aim of this retrospective cohort study was to evaluate systemic nickel in patients undergoing orthodontic therapy for a minimum period of 1?year. In this study, urinary nickel concentrations in 20 female and 10 male patients being treated with stainless steel appliances were measured using atomic absorption spectrophotometry. The same procedure was done on a control group of the patients?? same-gender near-age siblings (n?=?30). The effect of treatment and gender on urinary nickel levels were assessed using a repeated-measures two-way analysis of variance (ANOVA) and a Tukey test (???=?0.05). The mean treatment duration was 17.1?±?6.4?months (range, 12?C21). The mean nickel concentrations in male and female patients were 9.67?±?3.25 and 9.9?±?3.83???g/L, respectively. These statistics for male and female control subjects were 6.65?±?2.57 and 8.43?±?2.94???g/L, respectively. The ANOVA showed a statistically significant difference between the urinary nickel levels of the treatment and the control groups (P?=?0.009) but not between the genders (P?=?0.194). The interaction between gender and treatment was also nonsignificant (P?=?0.337). The Tukey test indicated that the increase in nickel was higher in male patients, in comparison to their brothers (P?<?0.05). It could be concluded that orthodontic therapy for longer durations with stainless-steel archwires might elevate slightly, but significantly, urinary nickel levels.     

Albumin Cys34 adducted by acrolein as a marker of oxidative stress in ischemia-reperfusion injury during hepatectomy

The aim of this study was to measure and identify the reactive carbonyl species (RCSs) released in the blood of humans subjected to hepatic resection. Pre-anesthesia malondialdehyde (MDA) plasma content (0.36?±?0.11?nmol/mg protein) remained almost unchanged immediately after anaesthesia, before clamping and at the 10th min after ischemia, while markedly increased (to 0.59?±?0.07?nmol/mg; p?<?0.01, Tukey’s post test) at the 10th min of reperfusion. A similar trend was observed for the protein carbonyls (PCs), whose pre-anesthesia levels (0.17?±?0.13?nmol/mg) did not significantly change during ischemia, while increased more than fourfold at the 10th min of reperfusion (0.75?±?0.17?nmol/mg; p?<?0.01, Tukey’s post test). RCSs were then identified as covalent adducts to the albumin Cys34, which we previously found as the most reactive protein nucleophilic site in plasma. By using a mass spectrometry (MS) approach based on precursor ion scanning, we found that acrolein (ACR) is the main RCS adducted to albumin Cys34. In basal conditions, the adducted albumin was 0.6?±?0.4% of the native form but it increased by almost fourfold at the 10th min of reperfusion (2.3?±?0.7%; p?<?0.01, t-test analysis). Since RCSs are damaging molecules, we propose that RCSs, and ACR in particular, are new targets for novel molecular treatments aimed at reducing the ischemia/reperfusion damage by the use of RCS sequestering agents.