Dr Mohammed Mahmoud Youssif

Lead toxicity remains a significant global health challenge, causing cancers and profound effects on the neurological, hepatic, cardiovascular, renal, skeletal, reproductive, and hematologic systems. Despite ongoing public health efforts, vulnerable populations, particularly children and those in lead-related occupations, continue to suffer from its impacts. This review article presents Spirulina platensis, a nutrient-rich cyanobacterium, as a promising dietary supplement with potential protective effects against lead toxicity. Spirulina's multifaceted mechanisms of action, including antioxidant properties, heavy metal chelation, anti-inflammatory effects, and immunomodulation, position it as a viable therapeutic option for mitigating lead-induced damage. A comprehensive evaluation of current in vitro and in vivo studies highlights Spirulina's ability to reduce oxidative stress and improve organ function in lead-exposed models. While the potential benefits of Spirulina are evident, challenges, such as variability in product quality and need for standardized protocols, must be addressed. This review emphasizes the importance of further research to explore the long-term effects of Spirulina supplementation and its integration into public health strategies aimed at reducing lead toxicity. Ultimately, Spirulina platensis represents a natural intervention that could enhance detoxification efforts and improve health outcomes for individuals affected by lead exposure.

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BACKGROUND: Juvenile-onset systemic lupus erythematosus (jSLE) is an uncommon yet severe autoimmune/inflammatory condition affecting multiple bodily systems, typically manifesting before the age of 18. This disease exhibits significant complexity, displaying considerable variation among patients. Its effects can range in severity from minor to fatal, characterized by a pattern of recurring flare-ups and periods of remission, making its natural progression difficult to predict.

AIM: The aim of this work is to investigate the correlation between semaphorin 3A and systemic lupus erythematosus patients who follow up at Pediatric Rheumatology Unit Children's Hospital at Cairo University.

MATERIALS AND METHODS: This cross-sectional research was performed at the Pediatric Rheumatology Unit Cairo University Children's Hospital and included cases with jSLE under treatment and follow-up from the period of August 2021 to August 2022.

RESULTS: Regarding demographic data of the studied subjects, highly significant variances were noted among the patient group and control group regarding age (years) and sex. However, there were non-significant variances among the patient group and control group concerning weight. In the current research, median (IQR) onset of disease was 2 (1-3) years, mean ± SD age at disease diagnosis was 8.98 ± 2.13 years, median (IQR) disease duration 2 (1-3) years, family history was negative in 36 (90.0%) patients and consanguinity was negative in 28 (70.0%). The distribution of the manifestations within the patients group was as follows 7 (17.5%) with mucocutaneous, 7 (17.5%) with vasculitis, 4 (10.0%) with serositis, 11 (27.5%) with cardiac, 17 (42.5%) with renal, 11 (27.5%) with GIT, 5 (12.5%) with hematological, and 4 (10.0%) with neurological manifestations. In addition, there were 2 (5.0%) with arthritis, 31 (77.5%) with arthralgia, and 2 (5.0%) with fever, mean ± SD systolic BP was 115.95 ± 8.38 and mean ± SD diastolic BP was 75.60 ± 6.11. Regarding treatments in the patients' group, the median steroid dose was 15 mg (5-25) with median duration of 2 (1-3), 38 (95.0%) patients received hydroxychloroquine with mean ± SD hydroxychloroquine dose of 205.26 mg ± 51.71. 23 (57.5%) patients received cyclophosphamide with mean ± SD number of cyclophosphamide doses 7.17 mg ± 2.42. Mycophenolate was received in 27 (67.5%) with mean ± SD dose of 614.07 mg ± 225.85. There were highly statistically significant differences between control group and patients' group concerning TLC, creatinine, and ESR. Highly statistically significant variance was noted among the control group and patients group concerning CRP. Regarding the patients' group, the mean ± SD serum C3 was 99.89 mg/dl ± 28.45, median (IQR) serum C4 was 14.5 mg/dl (8.8-25.5), and median (IQR) albumin creatinine ratio was 27 IU/ML (16-186). There was positive ANA with titre and pattern in 34 patients (85.0%), positive antids- DNA in 25 patients (62.5%), and positive anticardiolipin IgM and IgG in 5 patients (12.5%). Renal biopsy was found to be normal in 23 (57.5%), lupus nephritis class II, III in 3 (7.5 percent), lupus nephritis class III in 10 (25.0%), and lupus nephritis class IV in 4 (10.0%). Urine analysis results showed the following: normal in 28 (70.0%), albumin in 2 (5.0%), casts in 2 (5.0%), pus cell in 4 (10.0%), albumin + casts in 2 (5.0%) and albumin + pus cell in 2 (5.0%). Regarding semaphorin 3A level, a highly statistically significant variance was noted among the control and patients group concerning semaphorin 3A level found to be lower in cases than control with a p-value below 0.001. In patients' group, a negative correlation for semaphorin 3A with SBP, DBP, AST and ESR and also a positive correlation with steroid duration in the studied patients was noted. In addition, highly significant association between semaphorin 3A and positive CRP was also observed. However, no significant relationship between semaphorin 3A and SLE manifestations except arthritis was found related to semaphorin 3A level. ROC curve shows that the semaphorin 3A cut-off point to predict SLE ≤ 3 with sensitivity = 47.50, specificity=92.50, PPV=86.4, and NPV=63.8.

CONCLUSION: Reduced plasma Semaphorin 3A levels were found in this study; furthermore, their clinical relationship in SLE proposes their significant job in this illness. Furthermore, the ROC results demonstrated that Semaphorin 3A could be a new symptomatic biomarker in SLE with very high sensitivity for the determination of SLE, demonstrating that they might be helpful biomarkers for the evaluation of SLE. However, extra studies that focus on the potential role of Semaphorin 3A in SLE are needed.

Herein, sustainable, economical, ultrahigh surface area, and scalable nanoporous carbon nanoparticles were developed for efficient hydrogen storage and gas separation. Spherical casein nanoparticles (CNPs) were greenly developed using a one-pot solvent- free solid-state ball-milling method. The ball-milling time was varied between 24 and 72 h, and in turn, the average size of casein nanoparticles developed varied, recording 41.2 and 35.4 nm for 24 and 72 h, respectively. Secondly, the developed nanoparticles were carbonized, followed by chemical activation, yielding nanoporous carbon nanoparticles with superior textural properties and inherently doped with oxygenated and nitrogenated functional groups. The developed nanoporous carbon nanoparticles exhibited outstanding microporosity with ultrahigh BET-SSA of 3035.9 m2 g−1 and total pore volume of 1.73 cm3 g−1 with ultramicropores of size 0.56–0.68 nm. This is associated with intrinsic doping levels of oxygenated and nitrogenated surface groups. The developed nanoporous carbon adsorbent revealed high H2 storage capacities at 77 and 298 K, achieving 5.97 and 0.405 wt% at pressures of 70 and 80 bar, respectively. The isosteric heat of adsorption of H2 corroborated the synergistic role of microporosity and intrinsic doping of O and N species for boosting H2 interaction with the developed adsorbent, recording an average value of 8.68 kJ mol−1. On the other hand, the developed nanoporous carbon nanoparticles showed promising CO2 capture, achieving 22.35 mmol g−1 at 298 K and 30 bar, revealing its suitability for pre-combustion CO2 capture as well. Additionally, the CO2/H2 separation selectivity was also studied using ideal adsorbed solution theory (IAST) at different binary gas mixtures of 50:50, 40:60, and 20:80 at RT and 30 bar. Remarkably, the sustainable nanoporous carbon nanoparticles achieving CO2/H2 separation selectivity of 18.9, 28.45 and 75.89 for gas mixtures of 50:50, 40:60, and 20:80, respectively, revealing their potential for H2 purification applications.

This paper addresses the sustainable abstraction rate and depth, and the corresponding salinity, in a coastal aquifer as a result of abstraction from beach wells, which is applied on the coastal Nile Delta aquifer as a case study. The field measurements were conducted at West Port Said (WP site) Egypt, and included site visits, topographic survey, drilling of exploratory wells with depths ranging from 60 m to 500 m, pumping tests, water sampling and chemical analysis to identify the physical settings, geological, hydrogeological, and environmental characteristics of the study area and the surroundings. A conceptual model was developed for abstraction from WP site, with the aquifer, comprising five water-bearing layers spreading over three sub-aquifers separated by two clay confining layers. It also includes a surface coastal lake. Consequently, a numerical model was developed and validated to simulate drawdown and salinity at abstraction rates from 50,000 m3/d to 500,000 m3/d over a period of 50 years, which resulted in drawdowns of 9–84.2 m, and salinity levels range from 39,835 to 40,272 mg/L for abstraction rates of 50,000 m3/d and 500,000 m3/d, respectively. The model also included simulation of oil concentration at abstraction wells because of accidental oil spill in the sea. To generalize the conclusions for abstraction over the entire Nile Delta coastal aquifer, the numerical model developed for WP site is used to simulate abstraction at any site within the coastal aquifer with different settings, including presence or absence of coastal lake and clay confining units. It also addressed the impact of improved salinity of the coastal lake on the abstraction, mainly for salinity. Among all these scenarios at 50 year and abstraction rate of 500,000 m3/d, it was found that drawdown varies from lowest value of 54 m to highest value of 86.65 m, as well as salinity varies from lowest value of 38,629 mg/L to highest value of 41,878 mg/L. This leads to identify abstraction depth, salinity, drawdown and the daily maximum recommended sustainable abstraction rate from the subject coastal aquifer, when compared to the daily abstraction as per Egyptian government plan 2050, it was found that the Nile Delta aquifer could serve 50 % of the demand.

Hydrogen, as a renewable zero-carbon fuel, is an ideal alternative to internal combustion engine fuels. The paper numerically investigates the effect of piston geometry on lean combustion in hydrogen engines, focusing on early and late injection strategies. Two novel piston bowl designs, referred to as the right-concave piston and left-concave piston, were analyzed for their interaction with hydrogen jets during mixture formation and combustion processes. Validation of the numerical outputs were conducted using an experimental testbench. Results reveal that the right-piston had a stronger and larger scale tumble, compared to the flat-top piston, facilitating hydrogen diffusion. However, due to their early injection timing, mixture distribution at ignition timing was relatively uniform, resulting in comparable indicated thermal efficiency (ITE) and NOx emissions. Conversely, the left-concave piston demonstrated inferior ITE and higher emissions under single injection but achieved superior performance with an optimized dual injection strategy. This strategy improved mixture stratification increased thermal efficiency, and significantly reduced NOx emissions. The key findings highlight the critical role of piston geometry and injection strategy in optimizing hydrogen combustion engines for higher efficiency and lower emissions.

Hydrogen, as a renewable zero-carbon fuel, is an ideal alternative to internal combustion engine fuels. The paper numerically investigates the effect of piston geometry on lean combustion in hydrogen engines, focusing on early and late injection strategies. Two novel piston bowl designs, referred to as the right-concave piston and left-concave piston, were analyzed for their interaction with hydrogen jets during mixture formation and combustion processes. Validation of the numerical outputs were conducted using an experimental testbench. Results reveal that the right-piston had a stronger and larger scale tumble, compared to the flat-top piston, facilitating hydrogen diffusion. However, due to their early injection timing, mixture distribution at ignition timing was relatively uniform, resulting in comparable indicated thermal efficiency (ITE) and NOx emissions. Conversely, the left-concave piston demonstrated inferior ITE and higher emissions under single injection but achieved superior performance with an optimized dual injection strategy. This strategy improved mixture stratification increased thermal efficiency, and significantly reduced NOx emissions. The key findings highlight the critical role of piston geometry and injection strategy in optimizing hydrogen combustion engines for higher efficiency and lower emissions.

Water treatment has become a pressing global issue due to the increasing number of pollution sources. Among the major contributors to water contamination is the widespread use of dyes, such as Alizarin Red S, across various industries. In this study, Zn-MOF nanoparticles were prepared using the conventional solvothermal method and characterized through Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscope coupled with energy dispersive X-ray spectroscopy (SEM-EDX), Brunauer-Emmett-Teller (BET) analysis as well as thermogravimetric analysis (TGA). The adsorption performance of Zn-MOF nanoparticles for removing Alizarin Red S (ARS) was investigated using batch adsorption experiments. Key parameters, including Zn-MOF dosage, initial ARS concentration, pH and contact time were evaluated under ambient conditions. The results demonstrated an ARS removal efficiency of approximately 71% at pH 4, a Zn-MOF dosage of 1 g/L and a primary ARS concentration of 20 ppm within 40 min. Additionally, the material exhibited reusability for up to three cycles, maintaining a removal efficiency of 60%. Freundlich, Langmuir, and Temkin were three isotherm and kinetic models applied to illustrate the adsorption mechanism. Adsorption was found to align with the Langmuir isotherm model as well as following pseudo-second-order kinetics.

CVD-grown graphene was transferred to p-type silicon films using wet transfer technique to create Schottky junction-based photodiodes. Electrical transport and optoelectronic properties of the produced diode were explored to assess the performance of the device. Room temperature current–voltage (IV) curves of the structure showed a typical rectifying behavior. The barrier height obtained from capacitance–voltage measurements was quite consistent with that obtained from IV curves. The structure revealed enhanced responsivity of 1.25 A/W at wavelength of 850 nm. A reversible light-triggered switching response with an ON/OFF current ratio of 150 was achieved. A reversible switching feature was observed in dynamic response measurements with response and recovery durations of 300 and 340 ms, respectively.