Bifurcation analysis of motoneuronal excitability mechanisms under normal and ALS conditions.

Introduction: Bifurcation analysis allows the examination of steady-state, non-linear dynamics of neurons and their effects on cell firing, yet its usage in neuroscience is limited to single-compartment models of highly reduced states. This is primarily due to the difficulty in developing high-fidelity neuronal models with 3D anatomy and multiple ion channels in XPPAUT, the primary bifurcation analysis software in neuroscience. Methods: To facilitate bifurcation analysis of high-fidelity neuronal models under normal and disease conditions, we developed a multi-compartment model of a spinal motoneuron (MN) in XPPAUT and verified its firing accuracy against its original experimental data and against an anatomically detailed cell model that incorporates known MN non-linear firing mechanisms. We used the new model in XPPAUT to study the effects of somatic and dendritic ion channels on the MN bifurcation diagram under normal conditions and after amyotrophic lateral sclerosis (ALS) cellular changes. Results: Our results show that somatic small-conductance Ca2+-activated K (SK) channels and dendritic L-type Ca2+ channels have the strongest effects on the bifurcation diagram of MNs under normal conditions. Specifically, somatic SK channels extend the limit cycles and generate a subcritical Hopf bifurcation node in the V-I bifurcation diagram of the MN to replace a supercritical node Hopf node, whereas L-type Ca2+ channels shift the limit cycles to negative currents. In ALS, our results show that dendritic enlargement has opposing effects on MN excitability, has a greater overall impact than somatic enlargement, and dendritic overbranching offsets the dendritic enlargement hyperexcitability effects. Discussion: Together, the new multi-compartment model developed in XPPAUT facilitates studying neuronal excitability in health and disease using bifurcation analysis.

Evaluation of the Adsorption Efficacy of Bentonite on Aflatoxin M1 Levels in Contaminated Milk.

The existence of aflatoxin M1 (AFM1) in raw milk results in economic losses and public health risks. This research aims to examine the capability of bentonite to adsorb and/or eliminate AFM1 from various raw milk types. In addition, the effects of numerous bentonites (HAFR 1, 2, 3 and 4) on the nutritional characteristics of the milk were studied. Our findings revealed that goat milk had the highest value of AFM1 (490.30 ng/L) in comparison to other milks. AFM1 adsorption was influenced by applying bentonite (0.5 and 1 g) in a concentration-dependent manner for different time intervals (from 0 to 12 h). The percentage of AFM1 reached the maximum adsorption level after 12 h to 100, 98.5 and 98% for bentonites HAFR 3, 1 and 2, respectively. HAFR 3 (1 g bentonite) presented higher adsorption efficiency than other bentonites used in the phosphate buffer saline (PBS) and milk. Residual levels of AFM1 reached their lowest values of 0 and 1.5 ng/L while using HAFR 3 in PBS and milk, respectively. With regard to the influence of bentonite on the nutritional characteristics of milk, there was an increase in fat, protein and solid non-fat ratio while using HAFR 3 and 4, yet decreased lactose in comparison with the control. Scanning Electron Microscopy and Fourier Transform-Infrared Spectroscopy both identified bentonites as superior AFM1 binders. The results demonstrated that bentonite, particularly HAFR 3, was the most effective adsorbent and could thus be a promising candidate for the decontamination of AFM1 in milk.

Relationship Between Heat Shock Protein Expression and Obesity With and Without Metabolic Syndrome.

Background: Obesity is considered a chronic inflammatory disease in which the physiological mechanism responsible for reducing inflammation is weakened, prompting low-grade inflammation throughout the body. One of the key stress response systems that is dysregulated in obesity is the heat shock response, which is a critical defense mechanism that is activated in stressful conditions. Obesity is primary to metabolic syndrome (MetS) as it appears to lead to the increase in other MetS risk factors. Aim of the Study: We aimed to investigate the different expression levels of intracellular heat shock protein (iHSP) 70 and iHSP27 in obese patients with and without MetS and compare these levels to those of a lean control group. Patients and Methods: One hundred ten lean subjects were compared with 44 obese subjects without MetS and 56 obese subjects with MetS. HSP70 and HSP27 mRNA expression levels were measured by quantitative real-time polymerase chain reaction. Results: iHSP70 mRNA expression was significantly higher in obese subjects without MetS than in lean subjects (p = 0.04), whereas iHSP70 mRNA expression was significantly lower in obese subjects with MetS than in those without MetS (p = 0.02) as well as in those in the lean group (p = 0.03). iHSP27 mRNA expression was significantly lower in obese subjects with MetS than in those without MetS and in lean subjects (p = 0.037 and 0.031, respectively). Conclusion: We conclude that the intracellular expression levels of HSP70 and HSP27 may play an important role in the pathogenesis of MetS.

Effect of glycemic gap on short term outcome in critically ill patient: In zagazig university hospitals.

Both admission Blood glucose and previous glycemic state may affect critically ill patients; So Glycemic gap may be a good indicator of ICU outcomes. This study investigated the effect of glycemic gap on short term outcome in critically ill patient and the value of incorporation of the Glycemic Gap into the APACHE-II on its discriminative performance. SUBJECTS AND METHODS: This cross sectional study was conducted in medical ICU of Zagazig University Hospitals, March 2018 to September 2018; total numbers of 240 critically ill patients admitted to ICU were enrolled in. All of them were subjected to: full history taking, clinical examination, routine investigations, random blood sugar, hemoglobin A1c. ADAG, Glycemic Gap and APACHE II were calculated. RESULTS: Elevated glycemic gap was associated with an increased ICU mortality and APACHE-II score was a good predictor of ICU mortality in critically ill patients. CONCLUSIONS: Elevated glycemic gap was significantly associated with an increased ICU mortality that the glycemic gap can be used to assess the severity and prognosis of critically ill patients and their incorporation into the APACHE II score has increased its performance as a predictor of mortality.

Comparison between Ologen implant and different concentrations of Mitomycin C as an adjuvant to trabeculectomy surgery.

CONTEXT: Trabeculectomy is the most common surgical procedure for treatment of glaucoma. To improve success rates, adjuvants were utilized as Mitomycin C (MMC) and Ologen implant. AIMS: This study aims to establish efficacy and safety of Ologen implant versus MMC in trabeculectomy. SETTING AND DESIGN: A prospective, comparative clinical study was conducted at the Department of Ophthalmology, Assiut University, between December 2014 and April 2016. SUBJECTS AND METHODS: Patients with primary open-angle glaucoma (OAG), primary narrow-angle glaucoma and secondary OAG were assigned equally to trabeculectomy with Ologen, 0.4 mg/mL or 0.2 mg/mL MMC. The study outcome measures were reduction in intra-ocular pressure (IOP), success rates, survival analysis, and rate of complications. STATISTICAL ANALYSIS USED: SPSS software Version 17.0 (SPSS, Inc., IL, USA) was utilized. RESULTS: Thirty eyes were included in the study. Mean baseline IOP in Ologen, MMC 0.4 and MMC 0.2 groups were 27.43 ± 2.97, 28.4 ± 3.24, and 27.56 ± 2.69 mmHg, respectively. At week 24 follow-up, mean IOP in Ologen, MMC 0.4 and MMC 0.2 groups were 18.55 ± 3.18, 16.2 ± 3.22, and 16.93 ± 3.04 mmHg, respectively. No significant inter-group difference was noticed at any visits. Complete success was achieved in 10%, 40%, and 30%, whereas incomplete success in 70%, 50%, and 60%, respectively in Ologen, MMC 0.4 and MMC 0.2 groups. No treatment group difference was reported by Kaplan-Meier analysis. Shallow anterior chamber occurred more in Ologen and MMC 0.4 groups. A single case of serous choroidal effusion had occurred in MMC 0.4 group. CONCLUSION: Ologen implant is a promising alternative to MMC for improving the success rate of trabeculectomy.

Role of MicroRNA 126 in screening, diagnosis, and prognosis of diabetic patients in Egypt.

MicroRNAs (miRNAs), family of non-coding small RNAs, play a vital role in the regulation of blood glucose level. We aimed to investigate the relation of serum miRNA-126 expression with impaired glucose tolerance as well as type 2 diabetes mellitus (T2DM) patients with and without complications. One hundred healthy controls, eighty-six patients with IGT, and one hundred patients with T2DM were recruited in this study. Serum miRNA-126 expression was assessed by quantitative real-time polymerase chain reaction. We found a significant decrease of serum miRNA-126 expression between IGT patients as well as diabetic patients when both compared with controls and between diabetic patients compared to IGT patients. A significant decrease of serum miRNA-126 expression was detected in diabetic patients with complications compared to those without evident complications especially those with diabetic macrovascular complications and diabetic retinopathy. Serum microRNA-126 expression could be a good marker for diagnosis of IGT and T2DM as well as for monitoring the outcomes of such disease. © 2016 IUBMB Life, 68(6):452-458, 2016.