Development of a new medium containing date syrup for production of bleomycin by Streptomyces mobaraensis ATCC 15003 using response surface methodology

A combined statistical approach of orthogonal design and polynomial regression were applied to optimize the composition and concentration of a liquid fermentation medium for the production of bleomycin (BLM) by Streptomyces mobaraensis. Optimal conditions for maximal productivity were determined based on eight parameters at three different levels. The sources of carbon and nitrogen concentration and their interactions with other precursors were found to be statistically significant factors. When date syrup was used as an additional carbon source, higher BLM amount was obtained in comparison to glucose. It was found that the optimum nitrogen source was achieved with the use of soyabean meal. The combined orthogonal design and response surface methodology predicted optimal conditions for production of BLM to be 138 mg dl-1. A confirmatory experiment of the optimal medium composition produced 142 mg dl-1 in the fifth day fermentation at 30°C. The complex medium containing 40 gml-1 date syrup as additional carbon source enhanced the production of BLM by 73%. The combined statistical approach enabled rapid identification and integration of key medium parameters for optimizing secondary metabolite production and could be very useful in pharma-ceutical screening programs.Keywords: Bleomycin, Streptomyces mobaraensis, orthogonal design, medium optimization, date syrupAfrican Journal of Biotechnology Vol. 9(33), pp. 5450-5459, 16 August, 201

Physiographic Characteristics Along the Ibex Protectorate: Remote Sensing Application, Hotet Bani Tamim, Central Saudi Arabia

Tuwiaq plateau is one of the most characteristic physiographic components of central Saudi Arabia. The Middle Jurassic limestone was the result of the natural harmony between the Tethys sedimentation, tectonics, and climate. The plateau was studied within the Ibex Protectorate of Hotet Bani Tamim area. Remote sensing applications on satellite images of 2019 were able to measure the geomorphology, distinguish the sedimentary units, and emphasized the role of tectonics in dividing the plateau to step-like escarpment, elevated from 1080 m at Al-Onouk the extreme northwest to 600m at Al-Hulwah with an average slope of 0.8cmm-1. The slope at catchment reaches up to 70° while at the downstream not more than 16°. Two basins are detected at the Ibex protectorate, these are Wadi Meta’am basin and Wadi Bowydan- Nokhailan basin who down flow into Wadi Meta’am  and Wadi Berek respectively). Wadi Meta’am derives its water through three tributaries Al-Ghaba, Ghafar, and Al-Agmaa, while Wadi Bowydan, on the other hand, cuts deeper and drain water with Wadi Nokhailan downstream to Wadi Berek. The high-density dendritic drainage pattern with 5th and 6th order tributaries support the vulnerability of the area to flash flood hazards. The heavy rains were able to sculpt such an amazing geomorphosite and leave its finger prints  in the form of deep streams (about 140m depth), channel lags of cobbles and pebbles, Quaternary thick colluvium, water-saturated soils,  and karstic features  such as the small pool, calcretes and travertines. The present study seeks the importance to schedule the area within the program of development according to the vision 2030 and to add among the geoheritage sites Keywords: Remote sensing, GIS, Ibex Protectorate, physiography, land classification DOI: 10.7176/JEES/9-11-04 Publication date: November 30th 201

Screening for psychological distress among High School Graduates Accepted for Enrollment at Alexandria Faculty of Medicine: Academic year 2016/2017

Background: Mental and psychological health of adolescents in general and prospective medical students in particular is a priority area to investigate as it affects wellbeing of the future doctors.Objectives: The current research was conducted to screen first year medical students accepted for enrollment at Alexandria Faculty of Medicine to identify those with a high probability of having psychological distress before the start of academic courses as well as explore the sources of stress among them.Methods: A cross sectional survey of 779 high school graduates accepted for admission to Alexandria Faculty of medicine was conducted. Participants were approached on the days of obligatory pre-enrollment medical examination. The translated Arabic version of DASS 21 questionnaire was used to screen students for three negative emotional symptoms namely depression, anxiety and stress. Inquiry about age, sex, residency and type of high school was added.Results: More than a tenth of studied medical students (12.6%) suffered from severe or profound stress and 29.1% of them had mild to moderate stress. Moreover, one fifth (20%) of studied students were severely anxious and less than one third (29.3%) had mild to moderate anxiety. Severe and profound depression was diagnosed among 14.3% of students whereas, 18.7% them were moderately depressed. No association was found between any of studied negative emotional symptoms and the students’ educational background or their residency.Conclusion: Nearly half of the prospective medical students might have some sort of psychological distress before starting their study in the Faculty of Medicine. They should be investigated to verify diagnosis and start intervention to minimize its adverse effects on academic performance and advancement at the faculty. Stress management courses should be considered for all medical students.Keywords: Psychological distress, Prospective medical students, Adolescents’ psychological health, Depression, Anxiety, Stres

Bacteriophage ZCSE2 is a Potent Antimicrobial against Salmonella enterica Serovars: Ultrastructure, genomics and efficacy

© 2020 by the authors. Developing novel antimicrobials capable of controlling multidrug-resistant bacterial pathogens is essential to restrict the use of antibiotics. Bacteriophages (phages) constitute a major resource that can be harnessed as an alternative to traditional antimicrobial therapies. Phage ZCSE2 was isolated among several others from raw sewage but was distinguished by broad-spectrum activity against Salmonella serovars considered pathogenic to humans and animals. Lytic profiles of ZCSE2 against a panel of Salmonella were determined together with low temperature activity and pH stability. The morphological features of the phage and host infection processes were characterized using a combination of transmission electron and atomic force microscopies. Whole genome sequencing of ZCSE2 produced a complete DNA sequence of 53,965 bp. No known virulence genes were identified in the sequence data, making ZCSE2 a good candidate for phage-mediated biological control purposes. ZCSE2 was further tested against S. Enteritidis in liquid culture and was observed to reduce the target bacterium to below the limits of detection from initial concentrations of 107–108 Colony Forming Units (CFU)/mL. With a broad host-range against pathogenic Salmonella serovars, phage ZCSE2 constitutes a potential tool against a major cause of human and animal disease

Fetal Biometric Charts and Reference Equations for Pregnant Women Living in Port Said and Ismailia Governorates in Egypt

AIM: To construct new fetal biometric charts and equations for some fetal biometric parameters for women between 12th and 41st  weeks living in Ismailia and Port Said Governorates in Egypt.MATERIAL AND METHODS: This cross-sectional study was carried out on 656 Egyptian women (from Ismailia and Port Said governorates) with an uncomplicated pregnancy, and all were sure of their dates. The selected group was between the 12th and 41st weeks of gestation, recruited from the district general hospital in Ismailia and Port Said to measure ultrasonographically biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL), then for each measurement separate regression models were fitted to estimate both the mean and the Standard deviation at each gestational age.RESULTS: New Egyptian charts were reported for BPD, HC, AC, and FL. Reference equations for the dating of pregnancy were presented. The mean of the previous measurements at 12th and 41st weeks were as follows: (23.37, 98.72), (83.05, 336.12), (67.85, 332.57) and (12.50, 74.92) respectively.CONCLUSION: New fetal biometric charts and regression equations for pregnant women living in Port Said & Ismailia governorates in Egypt

Black metal thin films by deposition on dielectric antireflective moth-eye nanostructures

Although metals are commonly shiny and highly reflective, we here show that thin metal films appear black when deposited on a dielectric with antireflective moth-eye nanostructures. The nanostructures were tapered and close-packed, with heights in the range 300-600 nm, and a lateral, spatial frequency in the range 5-7 mu m(-1). A reflectance in the visible spectrum as low as 6%, and an absorbance of 90% was observed for an Al film of 100 nm thickness. Corresponding experiments on a planar film yielded 80% reflectance and 20% absorbance. The observed absorbance enhancement is attributed to a gradient effect causing the metal film to be antireflective, analogous to the mechanism in dielectrics and semiconductors. We find that the investigated nanostructures have too large spatial frequency to facilitate efficient coupling to the otherwise non-radiating surface plasmons. Applications for decoration and displays are discussed

Sanguinarine Induces Apoptosis Pathway in Multiple Myeloma Cell Lines via Inhibition of the JaK2/STAT3 Signaling.

Sanguinarine (SNG), a benzophenanthridine alkaloid, has displayed various anticancer abilities in several vivo and studies. However, the anticancer potential of SNG is yet to be established in multiple myeloma (MM), a mostly incurable malignancy of plasma cells. In this study, we aimed to investigate the potential anti-proliferative and pro-apoptotic activities of SNG in a panel of MM cell lines (U266, IM9, MM1S, and RPMI-8226). SNG treatment of MM cells resulted in a dose-dependent decrease in cell viability through mitochondrial membrane potential loss and activation of caspase 3, 9, and cleavage of PARP. Pre-treatment of MM cells with a universal caspase inhibitor, Z-VAD-FMK, prevented SNG mediated loss of cell viability, apoptosis, and caspase activation, confirming that SNG-mediated apoptosis is caspase-dependent. The SNG-mediated apoptosis appears to be resulted from suppression of the constitutively active STAT3 with a concomitant increase in expression of protein tyrosine phosphatase (SHP-1). SNG treatment of MM cells leads to down-regulation of the anti-apoptotic proteins including cyclin D, Bcl-2, Bclxl, and XIAP. In addition, it also upregulates pro-apoptotic protein, Bax. SNG mediated cellular DNA damage in MM cell lines by induction of oxidative stress through the generation of reactive oxygen species and depletion of glutathione. Finally, the subtoxic concentration of SNG enhanced the cytotoxic effects of anticancer drugs bortezomib (BTZ) by suppressing the viability of MM cells via induction of caspase-mediated apoptosis. Altogether our findings demonstrate that SNG induces mitochondrial and caspase-dependent apoptosis, generates oxidative stress, and suppresses MM cell lines proliferation. In addition, co-treatment of MM cell lines with sub-toxic doses of SNG and BTZ potentiated the cytotoxic activity. These results would suggest that SNG could be developed into therapeutic agent either alone or in combination with other anticancer drugs in MM