Immobilization of acetylcholinesterase in nanofibrous PVA/BSA membranes by electrospinning

Electrospinning, a simple and versatile method to fabricate nanofibrous supports, has attracted continuous attention in the field of enzyme immobilization. In this study, acetylcholinesterase (AChE) has been successfully immobilized in PVA nanofibers via electrospinning of a mixture of AChE, BSA as an enzyme stabilizing additive and PVA. The maximum activity recovery of immobilized AChE was about 40%. In comparison with free enzyme, the immobilized AChE showed improved stability while retaining a considerable amount of activity at lower pH values. Moreover, the immobilized AChE retained >34% of its initial activity when stored at 30°C for 100 days and retained 70% of its initial activity after ten consecutive reactor batch cycles.     

Kit ligand and glial‐derived neurotrophic factor as alternative supplements for activation and development of ovine preantral follicles in vitro

In vitro growth of preantral follicles has the potential to produce considerable numbers of competent oocytes for use in medicine, agriculture, and even wildlife conservation. The critical regulatory role of growth factors and hormones in the development of preantral follicles has been established. This study investigated the effect of glial‐derived neurotropic factor (GDNF) and kit ligand (KL) on the in vitro development of ovine preantral follicles. Results indicated that both GDNF and KL significantly improved activation of primordial follicles, similar to co‐addition of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF), which are commonly used for in vitro follicular development. Importantly, GDNF had a more profound effect on follicle health, development, and differentiation compared with KL alone. Furthermore, the combination of GDNF and KL in the presence of EGF and bFGF had a positive, synergic effect on health, development, and differentiation of preantral follicles, as determined by histological and hormonal assessments. The results of this study may provide a foundation for further studies that will unravel the molecular mechanisms of follicular development to further improve the current status of in vitro preantral follicle culture. Mol. Reprod. Dev. 80: 35–47, 2013. © 2012 Wiley Periodicals, Inc.     

Upregulation of Toll-like receptor 4 through anti-miR-Let-7a enhances blastocyst attachment to endometrial cells in mice

Despite encouraging advances in fertility technology, the success rate of an ongoing pregnancy is relatively low and predominantly associated with implantation failure. Inflammatory responses are beneficial in the fetomaternal interface and supposedly accelerate the chances for successful implantation. The current study aims to determine the effect of Toll-like receptor 4 (TLR4) overexpression in mouse blastocysts via Let-7a downregulation using intracytoplasmic sperm injection-sperm-mediated gene transfer on embryo attachment rate. The pLenti-III-GFP-miR-Off-Let-7a vector was transmitted to oocytes derived via in vitro maturation (IVM) and in vivo oocytes by using NaOH-treated spermatozoa. Let-7a and TLR4 expression levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), immunocytochemistry, and western blot analysis in both oocytes and embryos. Blastocyst adhesion on the endometrial cells was monitored by microscopic analysis. qRT-PCR results showed that Let-7a expression decreased in the IVM (GV-MII) oocytes compared to the in vivo oocyte (MII) group (p < .05). TLR4 showed a higher expression in GV-MII oocytes at both the gene and protein levels (p < .05). Following anti-miR-Let-7a transmission, the TLR4 expression level was significantly upregulated in embryos compared with the control groups (p < .05). Attachment and migration of trophoblasts cells towards endometrial cells dramatically increased compared to the control group (p < .05). Based on our results, we concluded that Let-7a might mediate embryo attachment through regulation of TLR4 expression levels.     

Bacterial infections in the early period after liver transplantation in adults: A prospective single-center cohort study

Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81–0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.     

Cultivation of Tetraselmis suecica using a fishmeal factory effluent: effect on the growth,biochemical composition,and nutrient removal

One of the main effluents from fishmeal plants is stickwater (STW) that causes a considerable number of environmental hazards. This study aimed to replace standard growth medium (F/2; as an enriched solution for growing most of the marine microalgae) of Tetraselmis suecica with different ratios of STW from a kilka fishmeal plant including 0% (control), 10%, 25%, 50%, 75%, and 100%. Results showed that the highest nutrient removal efficacy was obtained in 75% STW treatment, followed by the highest algal cell density (1.23 × 10⁷ cells mL^?1) (P <0.05). A significant increase in the concentrations of photosynthetic pigments (chlorophyll a, b) and lipid productivity was recorded in 75% STW treatment compared to others (P <0.05). The maximum contents of carotenoids and crude protein were obtained in 100% and 50% STW groups, respectively. The levels of saturated and monosaturated fatty acids were significantly increased by increasing the inclusion ratio of STW from 50 to 100% (P <0.05). However, the lowest level of polyunsaturated fatty acids was measured in 100% STW treatment. Overall, replacing F/2 with STW up to 75% is feasible to culture T. suecica with the highest biomass and lipid productivity.

     

Benefit of nicorandil using an immunologic murine model of experimental colitis

Inflammatory bowel disease (IBD) is a chronic inflammatory condition with an unknown etiology. Nicorandil, a potassium channel opener, has been used for many years for the treatment of angina. Recently, it has been shown that nicorandil possesses some novel traits such as anti-apoptotic, gastroprotective, free radical scavenging, and anti-inflammatory properties. Therefore, we set out to examine the possible beneficial effect of nicorandil in a rat model of IBD. Colitis was induced by rectal administration of 2,4,6-trintrobenzene sulphonic acid (TNBS) into rats. Groups of animals used in this study were sham, control, and exposure to dexamethasone, nicorandil, glibenclamid (a pure adenosine triphosphate sensitive potassium channel (KATP) blocker), or nicorandil plus glibenclamid. Drugs were administered by gavage and animals were sacrificed after 7 days. Biochemical markers, including TNF-α and IL-1β, ferric reducing/antioxidant power (FRAP), myeloperoxidase (MPO) activity and thiobarbitoric acid-reactive substance (TBARS), were measured in the homogenate of colonic tissue. Results indicate that nicorandil significantly reduces macroscopic and histological damage induced by TNBS. Nicorandil diminishes MPO activity and levels of TBARS, TNF-∢, and IL-1β in damaged colonic tissue with a concomitant increase in FRAP value (P<0.01). These effects were not reversed by coadministration of glibenclamide. In conclusion, nicorandil is able to ameliorate experimental IBD with a dose in which it does not show any anti-hypertensive effect, and the mechanism of which is partially or totally independent from KATP channels. It is hypothesized that nitric oxide donation and free-radical scavenging properties of nicorandil upregulate endothelial nitric oxide synthase may be responsible for this phenomenon. These findings suggest that nicorandil can be useful in treatment of IBD, although further investigations are needed to elucidate the mechanisms involved.     

A global treatments for coronaviruses including COVID-19

In late December 2019 in Wuhan, China, several patients with viral pneumonia were identified as 2019 novel coronavirus (2019-nCoV). So far, there are no specific treatments for patients with coronavirus disease-19 (COVID-19), and the treatments available today are based on previous experience with similar viruses such as severe acute respiratory syndrome-related coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and Influenza virus. In this article, we have tried to reach a therapeutic window of drugs available to patients with COVID-19. Cathepsin L is required for entry of the 2019-nCoV virus into the cell as target teicoplanin inhibits virus replication. Angiotensin-converting-enzyme 2 (ACE2) in soluble form as a recombinant protein can prevent the spread of coronavirus by restricting binding and entry. In patients with COVID-19, hydroxychloroquine decreases the inflammatory response and cytokine storm, but overdose causes toxicity and mortality. Neuraminidase inhibitors such as oseltamivir, peramivir, and zanamivir are invalid for 2019-nCoV and are not recommended for treatment but protease inhibitors such as lopinavir/ritonavir (LPV/r) inhibit the progression of MERS-CoV disease and can be useful for patients of COVID-19 and, in combination with Arbidol, has a direct antiviral effect on early replication of SARS-CoV. Ribavirin reduces hemoglobin concentrations in respiratory patients, and remdesivir improves respiratory symptoms. Use of ribavirin in combination with LPV/r in patients with SARS-CoV reduces acute respiratory distress syndrome and mortality, which has a significant protective effect with the addition of corticosteroids. Favipiravir increases clinical recovery and reduces respiratory problems and has a stronger antiviral effect than LPV/r. currently, appropriate treatment for patients with COVID-19 is an ACE2 inhibitor and a clinical problem reducing agent such as favipiravir in addition to hydroxychloroquine and corticosteroids.     

Evaluation of Exposure to Radiofrequency Electromagnetic Fields from Smart Utility Meters operating at 868 MHz

Power density and duty factor values were measured around smart utility meters operating at 868 MHz under laboratory-controlled conditions. The maximum 6-min averaged exposure recorded was 0.1 mWm⁻², which is less than 0.0024% of the corresponding 1998 ICNIRP general public reference level. Duty factors measured were less than 2.8%. This study found that the exposure contribution from Zigbee smart meter devices operating at 868 MHz is generally lower than, if not similar to, those operating at 2.4 GHz. © 2023 Crown copyright. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.