Bacterial lipid II analogs : novel in vitro substrates for mammalian oligosaccharyl diphosphodolichol diphosphatase (DLODP) activities

Mammalian protein N-glycosylation requires the transfer of an oligosaccharide containing 2 residues of N-acetylglucosamine, 9 residues of mannose and 3 residues of glucose (Glc3Man9 GlcNAc2) from Glc3Man9GlcNAc2-diphospho (PP)-dolichol (DLO) onto proteins in the endoplasmic reticulum (ER). Under some pathophysiological conditions, DLO biosynthesis is perturbed, and truncated DLO is hydrolyzed to yield oligosaccharyl phosphates (OSP) via unidentified mechanisms. DLO diphosphatase activity (DLODP) was described in vitro, but its characterization is hampered by a lack of convenient non-radioactive substrates. Our objective was to develop a fluorescence-based assay for DLO hydrolysis. Using a vancomycin-based solid-phase extraction procedure coupled with thin layer chromatography (TLC) and mass spectrometry, we demonstrate that mouse liver membrane extracts hydrolyze fluorescent bacterial lipid II (LII: GlcNAc-MurNAc(dansyl-pentapeptide)-PP-undecaprenol) to yield GlcNAc-MurNAc(dansyl-pentapeptide)-P (GM5P). GM5P production by solubilized liver microsomal proteins shows similar biochemical characteristics to those reported for human hepatocellular carcinoma HepG2 cell DLODP activity. To conclude, we show, for the first time, hydrolysis of lipid II by a eukaryotic enzyme. As LII and DLO are hydrolyzed by the same, or closely related, enzymes, fluorescent lipid II analogs are convenient non-radioactive substrates for investigating DLODP and DLODP-like activities

Effectiveness of Group Therapy Based on Acceptance and Commitment on Social and Health Adjustment of Nursing Students

Introduction: University students have a lot of problems in the field of adjustment especially social and health adjustment. Therefore, present research aimed to investigate the effectiveness of group therapy based on acceptance and commitment on social and emotional adjustment of nursing students. Methods: This research was carried out as a semi-experimental, with a pre-test and post-test design. The statistical population included all nursing students of Islamic Azad University of Pishva branch in 2015-16 academic year. 40 nurses were selected by voluntary sampling method and randomly assigned to two equal groups. The experimental group experienced 8 sessions of 90 minutes of education by group therapy based on acceptance and commitment. Groups completed the dimensions of social and health adjustment of Bell’s adjustment questionnaire. Data were analyzed using SPSS19 and by multivariate analysis of covariance method. Results: The findings showed there was a significant difference between experimental and control groups in the social and health adjustment. In the other words, group therapy based on acceptance and commitment significantly led to improve the social and health adjustment of nursing students (P≤0/05). Conclusion: The results are due to the importance of group therapy based on acceptance and commitment on increasing social and health adjustment of nursing students. Therefore, it is suggested that counselors and therapists improve the dimension of adjustment especially social and health adjustment using group therapies based on acceptance and commitment

Assessment of Electrical Brain Activity of Healthy Volunteers Exposed to 3.5 GHz of 5G Signals within Environmental Levels: A Controlled–Randomised Study

International audienceFollowing the recent deployment of fifth-generation (5G) radio frequencies, several questions about their health impacts have been raised. Due to the lack of experimental research on this subject, the current study aimed to investigate the bio-physiological effects of a generated 3.5 GHz frequency. For this purpose, the wake electroencephalograms (EEG) of 34 healthy volunteers were explored during two “real” and “sham” exposure sessions. The electromagnetic fields were antenna-emitted in an electrically shielded room and had an electrical field root-mean-square intensity of 2 V/m, corresponding to the current outdoor exposure levels. The sessions were a maximum of one week apart, and both contained an exposure period of approximately 26 min and were followed by a post-exposure period of 17 min. The power spectral densities (PSDs) of the beta, alpha, theta, and delta bands were then computed and corrected based on an EEG baseline period. This was acquired for 17 min before the subsequent phases were recorded under two separate conditions: eyes open (EO) and eyes closed (EC). A statistical analysis showed an overall non-significant change in the studied brain waves, except for a few electrodes in the alpha, theta, and delta spectra. This change was translated into an increase or decrease in the PSDs, in response to the EO and EC conditions. In conclusion, this studhy showed that 3.5 GHz exposure, within the regulatory levels and exposure parameters used in this protocol, did not affect brain activity in healthy young adults. Moreover, to our knowledge, this was the first laboratory-controlled human EEG study on 5G effects. It attempted to address society’s current concern about the impact of 5G exposure on human health at environmental levels

Exploring brain electrical activity in healthy volunteers exposed to 3.5 GHz radio frequencies: preliminary results

International audienc

Histopathological patterns of testicular biopsy in male infertility: A retrospective study from a tertiary care center in the western part of Saudi Arabia

Objective: To identify and categorize various pathological changes seen in testicular biopsies of males with infertility and to compare the results with data from other local and international studies. Materials and Methods: All testicular biopsies from males with infertility received by the Pathology Department of King AbdulAziz University Hospital, Jeddah, in the period from January 2004 until May 2010 are reviewed and histopathologically classified into seven categories as follows : Normal spermatogenesis, hypospermatogenesis, germ cell maturation arrest (GCMA), Sertoli cell only syndrome, seminiferous tubule hyalinization, mixed and discordant patterns. Results: One hundred testicular biopsies were identified in the computerized records of the Department of Pathology of King AbdulAziz University Hospital in the studied period. The age ranged from 22 to 70 years with a mean age of 24.5 years. The histopathological patterns were as follows: 14 (14%) cases were reported as normal spermatogenesis;(29, 29%) cases as hypospermatogesis; and 12 (12%) cases were reported as GCMA, mostly at the level of primary spermatocytes. The Sertoli cell only syndrome and the seminiferous tubule hyalinization categories were each reported in 16 cases (16%). Nine cases (9%) showed a mixed pattern. Discordant pattern was seen in 5 (5%) cases. Conclusion: Our study showed that hypospermatogenesis is the commonest pattern in testicular biopsies taken from males with infertility in our region. This study supports the recommendation of bilateral testicular biopsies when investigating male infertility