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Objective: The purpose of this study was to examine the effects of apocynin (APC), an inhibitor of NADPH oxidase (NOX), on high-fat diet (HF)-induced testis cytotoxicity. Methods: Wistar albino rats were divided into three groups as control, HF and HF+APC groups. Rats in HF and HF+APC groups were fed using HF for 16 weeks and in the last four weeks of this period vehicle solution or APC (25 mg/kg) was administered orally five days a week, respectively. Control group was fed with standart lab chow for 16 weeks. Cholesterol, triglyceride, high-density lipoproteins, leptin, estrogen, testosterone, LH and FSH were estimated in blood serum. Sperm parameters were analysed from the epididymis. Testicular malondialdehyde, 8‐hydroxy‐2‐deoxyguanosine, glutathione, superoxide dismutase and myeloperoxidase levels were estimated biochemically. Testicular morphology, proliferative, apoptotic and NOX2-positive cells were analysed histologically. HF-induced obesity caused significant alterations in serum lipid and hormone profiles. Testicular malondialdehyde, 8‐hydroxy‐2‐deoxyguanosine, and myeloperoxidase levels increased, glutathione and superoxide dismutase levels decreased in this group. Moreover, altered sperm parameters, increased degenerated seminiferous tubules, apoptotic and NOX2- positive cells and decreased proliferative cells were observed in the HF group. All these biochemical and histological alterations improved in the HF+APC group. Conclusion: HF-induced obesity causes altreations in lipid values, sperm parameters and testicular morphology by increasing oxidative stress through NOX2 activity. Apocynin might prevent testis damage via regulating oxidant/antioxidant balance.

The seminiferous tubules where spermatogenesis occurs are enveloped and protected by the Sertoli cells to support germ cells undergoing meiosis to produce haploid gametes. Clearly, induction of apoptosis in seminiferous tubules leads to abnormalities in spermatogenesis and male infertility. Studies demonstrated that increased hyperlipidemia impairs male infertility and spermatogenesis by enhancing seminiferous tubules apoptosis. However, molecular mechanisms underlying high-cholesterol-mediated testicular damage remain poorly elucidated. In this scope, we established a rabbit model and investigated the role of endoplasmic reticulum (ER) stress on high cholesterol diet induced seminiferous tubule apoptosis. Histopatological examinations revealed increased seminifer tubule apoptosis in testes of rabbits fed high cholesterol diet. In addition, phosphorylated forms of IRE1 and PERK, two well-identified markers of ER stress, were significantly induced in accordance with high cholesterol diet. High cholesterol diet also exhibited CHOP induction in testes, indicating increased ER stress related apoptosis. Supplementation of α-tocopherol significantly attenuated cholesterol mediated ER stress, and restored seminiferous tubules apoptosis. Taken together, our findings suggest that α-tocopherol might be capable to reduce testicular damage via ameliorating histopatological features and inhibiting seminiferous tubules apoptosis in hypercholesterolemic rabbits.

Aims The purpose of the present study was to investigate the potential antioxidant, anti-apoptotic and sperm function-preserving effects of estrogen, estrogen receptor (ER)α and ERβ agonists in a rat model of testis torsion-detorsion (T/D). Main methods Under anesthesia, 6–8-week-old male Sprague-Dawley rats underwent sham-operation or testicular torsion by fixing left testis rotated at 720° for 2 h. After detorsion, rats were treated with ERα agonist (1 mg/kg/day, subcutaneously, sc) or ERβ agonist (1 mg/kg/day, sc) or estradiol (E2, 1 mg/kg/day, in drinking water) or vehicle on the following two days. On the third day, testicular blood-flow was recorded and then left testes were extracted for molecular and histochemical analysis. Key findings The findings showed that reduced testicular blood-flow following torsion was partially restored on the 3rd day of detorsion, while treatments with either of the ER agonists or E2 returned blood flow fully back to the control levels. When the testis-torsioned rats were given ERβ agonist during the detorsion period, tubular injury was lessened, sperm count and motility were increased, while the production of reactive oxygen metabolites and apoptosis in the testis tissues were totally suppressed. Although a down-regulated expression of androgen receptor (AR) along with a reduction in serum testosterone level was observed in the vehicle-treated T/D group, all three treatments up-regulated the expressions of AR and its mRNA, while ERα agonist and E2 suppressed the testosterone level. Significance ERβ receptor activation during the post-ischemic period may be beneficial in protection against torsion-related oxidant testicular injury and infertility.

Testicular torsion causes ischemia-reperfusion injury and an increased risk of infertility. Nesfatin-1 is a novel peptide with antioxidant, anti-inflammatory and anti-apoptotic properties. In the present study, we aimed to investigate the putative beneficial effects of nesfatin-1 on oxidative injury and impaired testicular function induced by testis torsion. Under anesthesia, male Sprague-Dawley rats (180–230 g; n = 24) had sham-operation or they underwent testicular torsion by rotating the left testis 720° and fixing it for 2 h, followed by a 2-h detorsion. Rats in each group were treated intraperitoneally with either nesfatin-1 (0.3 μg/kg) or saline prior to the torsion or sham-torsion. At the end of the 4-h experimental period, tissue samples were removed for evaluation of spermatozoa, molecular and histochemical analyses. In saline-treated torsion/detorsion group, a high percentage of abnormal spermatozoa with head defects was observed, which was abolished in nesfatin-1-treated torsion/detorsion group. The levels of 8-OHdG, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, caspase-3 were increased in the saline-treated torsion/detorsion group as compared to sham-operated group, while nesfatin-1 pre-treatment significantly decreased the expressions of the pro-inflammatory cytokines, depressed apoptosis, and also reduced the tubular degeneration. In addition, nesfatin-1 in torsion/detorsion group elevated expressions of transforming growth factor (TGF)-beta and reduced expressions of protein kinase B (AKT) and cAMP response element binding protein (CREB) in the testis tissue. The present findings show that nesfatin-1, by regulating AKT and CREB signaling pathways and pro-inflammatory/anti-inflammatory cytokine balance, preserves the spermatogenic cells and ameliorates torsion-detorsion-induced tubular degeneration.

Low energy, replica-based, and cryogenic scanning electron microscopy, and reflected visible light and fluorescence modes of confocal laser scanning microscopy, were applied to the imaging of mobile, non-equilibrium polymer-thickened and gelled-foams in porous media. As a result information was obtained about the morphology of some non-equilibrium foam lamellae in real porous media. In contrast to equilibrium (or near-equilibrium) foam, the structure of these non-equilibrium, viscous foams flowing through porous rock is quite similar to that observed in etched-glass micromodels. The foam films are lamellar, three-dimensionally arranged in various structures, and exhibit foam lamellae thicknesses ranging from about 1–12 μm. This thickness range is much narrower than is observed for bulk dynamic foams. The present measurements also show that foam lamellae in porous media can extend for considerable distances, greater than the length of individual pores, if oriented parallel to the overall direction of flow. In other cases, foam lamellae can span across the entrances to multiple pores. In the context of improved oil recovery, the latter configuration would cause blocking and diverting of injected fluids whereas the former configuration would cause only reduced permeability of the pores to injected fluids. These results are important to the optimal design of polymer-thickened and delayed-gelling foams for water shut-off applications in the near-wellbore regions of oil and gas producing wells, and for blocking and diverting applications in reservoirs undergoing secondary and tertiary flooding processes.

The variation of the critical micelle concentration (cmc) has been determined for sodium dodecyl sulfate (SDS) in water and in increasing concentrations of 1-butanol (C 4 OH) at temperatures ranging from 25 to 55 °C. Estimates of the thermodynamic parameters of micellization (Δ mic G o , Δ mic H o , and Δ mic S o ) are obtained from the variation of the ln X cmc with the absolute temperature (method 1). In addition, the enthalpies of micellization have been measured directly for the above systems and SDS/1-pentanol (C 5 OH) mixed micelles, by use of isoperibol solution calorimetry (method 2) over the same temperature range. The results from both methods, as a function of increasing temperature, indicate a shift in the driving force for the formation of micelles in the direction of decreasing enthalpy, in agreement with the literature. However, as a function of increasing alcohol concentration, the enthalpies from methods 1 and 2 are not comparable. Some possible reasons for the discrepancy will be discussed. Finally, we have examined the influence of the cosurfactant (alcohol) chain length on the thermodynamics of mixed micellization.

The fractional Fourier transform is a signal processing tool which is strongly associated with optical data manipulation. It has fast computational algorithms and it suggests solutions to interesting signal processing tasks. In this paper we review its properties as well as present a new set of its applications for blind source separation of images and for RF photonics (a field in which photonic devices are used to process RF signals). © 2007 Pleiades Publishing, Ltd.