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This master's thesis presents an advanced study on the functionalization of graphene with amines and metallic nanoparticles to enhance its antimicrobial properties, within the field of applied chemistry and nanoscience. Researcher Osama Abdelsattar aims to develop hybrid nanomaterials with high biological activity for potential medical and environmental applications, such as surface sterilization and water purification. The study involved preparing graphene samples functionalized with amine groups and subsequently decorated with silver, copper, and gold nanoparticles using wet chemical synthesis and controlled deposition techniques. The resulting composites were characterized using XRD, FTIR, SEM, and TEM analyses to determine their crystalline structure and surface morphology. Findings revealed that amine functionalization improved the homogeneous distribution of nanoparticles on the graphene surface, increasing surface reactivity and significantly enhancing antibacterial and antifungal activity. Biological assays demonstrated strong inhibition of E. coli and Staphylococcus aureus compared with free nanoparticles, confirming the synergistic effect of the graphene-based hybrid system. The researcher concludes that amine-modified graphene combined with metallic nanoparticles represents a promising approach for developing antimicrobial materials applicable in medical devices, filtration membranes, and protective coatings. The study recommends further exploration of other bioactive molecules to optimize performance for industrial and environmental uses. Abstract Written by Dar AlMandumh, 2025, Using AI.

In this thesis, fully developed, turbulent channel flows with smooth walls, with one rough and one smooth wall and with two rough walls, were studied, providing some useful and extended information about these kinds of flows. Fully developed, turbulent plane smooth channel flows were studied theoretically and experimentally. A Reynolds number range up to 1.1*10^5 was covered. The value of the von Karman constant, was found to be 1/e for this kind of flow, confirming the recent findings of Zanoun and Durst [2003]. Similarity conditions between channel flows with smooth surfaces, which possess different dimensions, were investigated theoretically. Experiments were carried out to check the theoretical findings and very good agreement was obtained. Another objective of the present work concerned fully developed, turbulent plane channel flows with one rough and one smooth wall. This kind of flow shows interesting properties that have not been studied systematically, in spite of the availability of suitable experimental and numerical means. The maximum velocity lies off-centre, closer to the smooth wall, and its location is not identical to that of zero shear stress of the flow. Furthermore, the mean velocity distribution close to the rough wall can only be plotted in wall coordinates if the wall location for zero shear stress could be defined. Methods to do this are given utilising a two-component LDA system that was employed to measure the mean velocity profiles and the Reynolds stress profiles for exact determination of the corresponding position of the zero shear stress. Using the available theoretical and experimental facilities, the effective height of the channel was determined as well as the reference point, which is the middle of the channel, for the velocity measurements. Fully developed, turbulent plane channel flows with rough surfaces were also studied in some depth. Previously, to calculate the shift between the smooth log law lines and the rough ones, one needed information about the height of the employed roughness. Without roughness height information, theoretical investigations were carried out to calculate the shift between the smooth log law line and the rough ones. The procedure was confirmed through corresponding experimental measurements. Furthermore, a new method to measure the static pressure in the rough regime was successfully introduced using Pitot tubes. Finally, some of the theoretical findings were confirmed by the data of Nikuradse, available in the literature, for smooth and the rough pipe flows.

Background Laparoscopic splenectomy (LS) is currently well-established as a standard technique for splenectomy. Robotic splenectomy (RS) is being introduced as a new minimally invasive alternative. The current study aims to directly compare RS and LS specifically in the pediatric population undergoing splenectomy for non-traumatic indications. Methods We performed a systematic search in four databases: PubMed, Web of Science, Scopus and Cochrane CENTRAL in November 2024. We included studies that compared outcomes of RS and LS in pediatric patients. We extracted the amount of blood loss, operation time, length of hospital stay, the number of patients who needed blood transfusion or were converted to open approach and post-operative complications. Finally, RevMan software was adopted for meta-analysis. Results Six retrospective studies met our eligibility criteria and were included in the current systematic review and meta-analysis with a total of 248 patients, of which 123 and 125 children underwent RS and LS respectively. Blood loss was significantly lower in RS group (MD = -56.95, P  = 0.01). Operation time, hospital stay, the need for blood transfusion and post-operative complications showed no significant difference between both RS and LS groups. Despite the overall good quality of the included studies, the GRADE quality of evidence was considered very low due to the observational nature of the included studies, small sample sizes and high variability between outcomes of different studies. Conclusion Our study guides the existing literature towards a possible non-inferior status of robotic splenectomy compared to the well-established laparoscopic splenectomy in most clinical outcomes. Blood loss was significantly lower in children who underwent robotic splenectomy, but small sample size limits generatability of such finding. The challenge of higher costs of robotic splenectomy needs to be addressed in well-designed cost-effectiveness studies.

Introduction Despite significant progress in acute stroke management, the burden of persistent motor impairments necessitates ongoing research into novel therapeutic strategies. Our study aims to study if antidepressants can effectively improve the motor function and functional independence in patients after stroke. Methods This meta-analysis encompassed Randomized Controlled Trials (RCTs) that enrolled adult stroke patients and compared any antidepressant drug against placebo, and reporting motor outcomes. We excluded studies which reported only cognitive outcomes or single arm studies with no comparator. We searched PubMed, Scopus, Cochrane, and Web of Science for records from inception up to August 2024. Outcomes data were pooled as standardized mean differences (SMDs) with the corresponding 95% confidence intervals (CI). Risk of Bias 2 (RoB2) tool was considered for quality assessment of the included studies. Results The preliminary search yielded 22 articles. A total of 11,396 patients were included, with a majority being elderly. Anti-depressants, primarily fluoxetine and citalopram, significantly improved Fugl Meyer Motor scale Scores (FMMS) at the endpoint (SMD = 0.79, 95%CI [0.056, 1.02], p-value < 0.00001) and change from baseline (SMD = 0.75, 95%CI [0.27, 1.24], p-value = 0.002), suggesting a substantial positive effect equivalent to a large effect size, potentially reflecting significant improvements in motor control and function. There wasn’t a significant subgroup difference between fluoxetine, citalopram, and selegiline. Also, Barthel index (BI) scores endpoints were significantly improved by antidepressants (SMD = 0.54, 95%CI [0.12, 0.96], p-value = 0.01) and change from baseline (SMD = 0.46, 95%CI [0.02, 0.9], p-value = 0.04), indicating a moderate positive effect, likely representing noticeable gains in independence for activities of daily living. There was a significant difference in both BI endpoints score and change from baseline ( P  < 0.00001) between subgroups favoring escitalopram. However, anti-depressants did not improve modified Rankin Scale (mRS) Scores (SMD = 0.06, 95%CI [-0.01, 0.12], p-value = 0.08). There wasn’t a significant subgroup difference between fluoxetine and citalopram (p-value = 0.17). Based on RoB2, 12 studies were rated as having an overall low risk of bias, four were rated as having some concerns, and six were assessed as high risk. Conclusion Certain antidepressants may enhance motor performance and independence in performing activities of daily living during post-stroke recovery among elderly patients. Fluoxetine was the most common antidepressant described in the literature with significant improvement in motor (FMMS) functional (BI) scales. However, substantial heterogeneity and potential study biases warrant cautious interpretation. Rigorous, large-scale RCTs are necessary to verify these findings and establish long-term safety profiles. They will also help define the optimal therapeutic strategies before routine clinical use is considered.

Objective We sought to prospectively evaluate the impact of previously failed SWL on subsequent URS outcomes in the treatment of upper urinary tract stones. Materials and methods Between May 2021 and May 2023, one hundred thirty-six patients with proximal ureteral stones < 1.5 cm and renal stones < 2.5 cm who were candidates for URS were prospectively assigned to a non-SWL group, which included patients without a history of failed SWL before URS, and a post-SWL group, which included patients with a history of failed SWL before URS. The success rate was the primary outcome. The perioperative data of the two groups were compared. Results The stone-free rate was 83.3% in the post-SWL group versus 81.3% in the non-SWL group, and 8.3% in the post-SWL group versus 9.4% in the non-SWL group had clinically insignificant residual fragments. There was no significant difference in the stone-free rate or success rate between the groups. No significant differences in intraoperative fluoroscopy time, operative time, intraoperative stone appearance, perioperative complications, or the presence of embedded fragments in the ureteral mucosa were detected between the two groups. Conclusion Compared with patients who underwent primary URS, patients who underwent salvage URS for upper urinary tract stones had similar stone-free rates, success rates, operative times, fluoroscopy times, and complication rates without any significant differences.

A mechanistic understanding of the dynamic interactions between the mitochondria and the gut microbiome is thought to offer innovative explanations for many diseases and thus provide innovative management approaches, especially in GIT-related autoimmune diseases, such as ulcerative colitis (UC). β-Glucans, important components of many nutritious diets, including oats and mushrooms, have been shown to exhibit a variety of biological anti-inflammatory and immune-modulating actions. Our research study sought to provide insight into the function of β-glucan and/or fidarestat in modifying the microbiome/mitochondrial gut axis in the treatment of UC. A total of 50 Wistar albino male rats were grouped into five groups: control, UC, β-Glucan, Fidarestat, and combined treatment groups. All the groups were tested for the presence of free fatty acid receptors 2 and 3 (FFAR-2 and -3) and mitochondrial transcription factor A (TFAM) mRNA gene expressions. The reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and ATP content were found. The trimethylamine N-oxide (TMAO) and short-chain fatty acid (SCFA) levels were also examined. Nuclear factor kappa β (NF-kβ), nuclear factor (erythroid-2)-related factor 2 (Nrf2) DNA binding activity, and peroxisome proliferator-activated receptor gamma co-activator-1 (PGC-1) were identified using the ELISA method. We observed a substantial increase FFAR-2, -3, and TFAM mRNA expression after the therapy. Similar increases were seen in the ATP levels, MMP, SCFA, PGC-1, and Nrf2 DNA binding activity. The levels of ROS, TMAO, and NF-kβ, on the other hand, significantly decreased. Using β-glucan and fidarestat together had unique therapeutic benefits in treating UC by focusing on the microbiota/mitochondrial axis, opening up a new avenue for a potential treatment for such a complex, multidimensional illness.

Background There is no consensus on the initial treatment modality for unilateral Wilms tumor (WT) in Egypt. This multicenter study investigates the factors guiding the decision-making between primary surgery and delayed resection for this tumor in our clinical practice. A retrospective analysis was conducted on all patients with unilateral, non-metastatic WT treated at four major Egyptian institutions from January 2019 to January 2024. Clinical characteristics, management details, and outcomes were reviewed. Timing of nephrectomy was analyzed in relation to tumor characteristics such as size, midline crossing, suspicion of perinephric spread, intravascular extension, and retroperitoneal lymphadenopathy. Results The study included 112 patients with a median age of 2.8 years. The median largest tumor diameter was 12 cm (range, 7–16 cm). Primary nephrectomy was performed in 62 patients (55.4%), while 50 (44.6%) underwent delayed resection after biopsy and neoadjuvant chemotherapy. Tumors larger than 12 cm and tumors crossing the midline were reported in 38.5% and 35% of all patients, respectively. Suspicion of perinephric spread was noted in 31% of patients, and significant lymphadenopathy in 13.5%. Intravascular tumor thrombus was detected in 7 patients (6.25%) at various locations. Statistically significant differences were observed between the primary surgery and delayed resection groups regarding suspicion of perinephric spread, intravascular thrombus, and retroperitoneal lymphadenopathy ( p -value < 0.001, 0.002, and < 0.001, respectively). However, tumor diameter and midline crossing showed no significant differences ( p -value = 0.137 and 0.152, respectively). At a median follow-up of 37 months, seven patients experienced relapses, and six died. The 3-year overall and event-free survival for all patients were 91% and 89%, respectively. Conclusions In our study, tumors larger than 12 cm and/or crossing the midline, if without other risk factors, did not significantly influence the decision for primary nephrectomy in unilateral, non-metastatic WT. However, suspicion of perinephric spread, intravascular thrombus (even at the level of renal veins), and evident retroperitoneal adenopathy were crucial factors in choosing delayed resection.

Background Klippel-Trenaunay syndrome (KTS) refers to a combination of capillary malformation + venous malformation ± lymphatic malformation + limb overgrowth. In this report, we present a case series of combined slow-flow vascular malformations (KTS) managed at a multidisciplinary vascular anomalies clinic. Results The study included 26 patients diagnosed as having combined slow-flow vascular malformations (KTS) during the period 2015 through 2024. The age at presentation ranged between 1 month and 15 years (mean = 35.9 months; median = 24 months). Eighteen out of the 26 patients were males (69.2%). Except for three cases, the lower extremities were always involved, whether unilateral, bilateral, or in conjunction with other regions in the body (commonly the lower trunk, abdomen, and pelvis). All cases presented with asymmetrical and distorted body contour. Other common complaints included pain and bleeding from skin lesions. Conservative management was the mainstay of treatment. Laser ablation, injection sclerotherapy, and/or surgery were used in selected cases to manage symptoms. Sirolimus was an effective medical treatment to control recurrent bleeding from diffuse skin lesions and mucous membranes. Alpelisib, a direct PI3K inhibitor, holds promising potential in the future treatment of KTS; however, it has not yet been used in our current patient cohort. Marginal vein should be treated by surgery or endovascular occlusions if deep veins are not absent. Conclusion Klippel-Trenaunay syndrome is a combination of slow-flow vascular malformations mostly occurring in the lower extremities with tissue overgrowth. The venous anomalies (lateral marginal vein) represent the primary source of complications and should be treated after ruling out abnormalities of the deep venous system. Localized symptomatic lesions may be treated with targeted interventions such as surgical excision, injection sclerotherapy, or laser ablation. Sirolimus is a systemic medication with promising outcomes in the treatment of such cases with complex and diffuse anomaly.

Background Glutaric aciduria type 1 is a rare neurometabolic disease with high morbidity. Objective To describe the MR imaging abnormalities in glutaric aciduria type 1 and to identify any association between the clinical and imaging features. Materials and methods MRI scans of 29 children (mean age: 16.9 months) with confirmed diagnosis of glutaric aciduria type 1 were retrospectively reviewed. Gray matter and white matter scores were calculated based on a previously published pattern-recognition approach of assessing leukoencephalopathies. Hippocampal formation and opercular topography were assessed in relation to the known embryological basis. MRI scores were correlated with morbidity score. Results The most consistent MRI abnormality was widened operculum with dilatation of the subarachnoid spaces surrounding underdeveloped frontotemporal lobes. Incomplete hippocampal inversion was also seen. The globus pallidus was the most frequently involved gray matter structure (86%). In addition to the central tegmental tract, white matter abnormalities preferentially involved the central and periventricular regions. The morbidity score correlated with the gray matter abnormality score ( P  = 0.004). Patients with dystonia had higher gray matter and morbidity scores. Conclusion Morbidity is significantly correlated with abnormality of gray matter, rather than white matter, whether secondary to acute encephalopathic crisis or insidious onset disease.

Salinity is a widespread abiotic stress that devastatingly impacts wheat growth and restricts its productivity worldwide. The present study is aimed at elucidating biochemical, physiological, anatomical, gene expression analysis, and agronomic responses of three diverse wheat genotypes to different salinity levels. A salinity treatment of 5000 and 7000 ppm gradually reduced photosynthetic pigments, anatomical root and leaf measurements and agronomic traits of all evaluated wheat genotypes (Ismailia line, Misr 1, and Misr 3). In addition, increasing salinity levels substantially decreased all anatomical root and leaf measurements except sclerenchyma tissue upper and lower vascular bundle thickness compared with unstressed plants. However, proline content in stressed plants was stimulated by increasing salinity levels in all evaluated wheat genotypes. Moreover, Na+ ions content and antioxidant enzyme activities in stressed leaves increased the high level of salinity in all genotypes. The evaluated wheat genotypes demonstrated substantial variations in all studied characters. The Ismailia line exhibited the uppermost performance in photosynthetic pigments under both salinity levels. Additionally, the Ismailia line was superior in the activity of superoxide dismutase (SOD), catalase activity (CAT), peroxidase (POX), and polyphenol oxidase (PPO) enzymes followed by Misr 1. Moreover, the Ismailia line recorded the maximum anatomical root and leaf measurements under salinity stress, which enhanced its tolerance to salinity stress. The Ismailia line and Misr 3 presented high up-regulation of H+ATPase, NHX2 HAK, and HKT genes in the root and leaf under both salinity levels. The positive physiological, anatomical, and molecular responses of the Ismailia line under salinity stress were reflected on agronomic performance and exhibited superior values of all evaluated agronomic traits.