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Ohmori, T., M. S. El-Deab, and M. Osawa, "Electroreduction of Nitrate Ion to Nitrite and Ammonia on a Gold Electrode in Acidic and Basic Sodium and Cesium Nitrate Solutions", Journal of Electroanalytical Chemistry, vol. 470, pp. 46-52, 1999.
Ohnsorge, J. A. K., K. H. Salem, A. Ladenburger, U. M. Maus, and M. Weißkopf, "Computer-assisted fluoroscopic navigation of percutaneous spinal interventions", European Spine Journal, vol. 22, no. 3: Springer-Verlag, pp. 642-647, 2013. AbstractWebsite
Ohsaka, T., and M. S. El-Deab, "Development of non-platinum-based electrocatalysts for oxygen reduction", Recent Research Developments in Electrochemistry, Kerala, Transworld Research Network, 2004.
Ohsaka, T., and M. S. El-Deab, "Electrocatalysis by Nanoparticles: Fabrication and Electrochemical Applications of Tailor-Designed Nanoparticles-Based Electrocatalysts", Electrochemistry (Japan), vol. 75, issue 11, pp. 858-866, 2007.
Ohtsuka, N., M. E. Shabshiry, M. Ismail, A. Faessler, and J. Aichelin, "Does photon production in heavy-ion collisions depend on the equation of state?", Journal of Physics G: Nuclear and Particle Physics, vol. 16, no. 8, pp. L155-L161, 1990. AbstractWebsite

Photon production cross sections in 12C-12C and 40Ca-40Ca collisions at Elab=84 and 200 MeV/A are calculated in the framework of the quantum molecular dynamics approach using the medium-dependent NN cross section obtained from the G matrix. Photons are assumed to be produced by incoherent pn bremsstrahlung and a simple classical expression for the production cross section is used. The effects of the equation of state for nuclear matter on the photon production cross section are studied in detail. In the 12C-12C collision, the authors found little difference in the photon cross section due to differences in the equation of state both at 84 and 200 MeV/A. In the 40Ca-40Ca collision, slightly more high-energy photons are produced in the case of the soft equation of state and the difference is slightly larger at higher incident energies.

Oing, C., I. Verem, W. Y. Mansour, C. Bokemeyer, S. Dyshlovoy, and F. Honecker, "5-Azacitidine Exerts Prolonged Pro-Apoptotic Effects and Overcomes Cisplatin-Resistance in Non-Seminomatous Germ Cell Tumor Cells.", International journal of molecular sciences, vol. 20, issue 1, pp. 21-32, 2018 Dec 21, 2019. Abstract

Despite high cure rates, about 20% of patients with advanced germ cell tumors (GCTs) fail cisplatin-based chemotherapy. High levels of DNA methylation have been identified in GCTs and linked to cisplatin resistance. Here, we examined the effects of DNA hypomethylating 5-azacitidine (5-aza) on two embryonal carcinoma cell lines (NCCIT, 2102Ep) and their cisplatin-resistant isogenic derivatives. Effects on cell viability and cisplatin sensitivity were assessed by the trypan blue exclusion method. Western blotting was used to examine induction of apoptosis 5-aza and results were validated by flow cytometry. Single agent treatment with 5-aza strongly impacted viability and induced apoptosis at low nanomolar concentrations, both in cisplatin-sensitive and -resistant cell lines. 5-aza exerted an immediate apoptotic response, followed by a prolonged inhibitory effect on cell viability and cell-cycle progression. Sequential treatment with 5-aza and cisplatin reduced cellular survival of the cisplatin-resistant sublines already at nanomolar concentrations, suggesting a partial restoration of cisplatin sensitivity by the compound. 5-aza demonstrated anti-tumor activity as a single agent at low nanomolar concentrations in GCT cells, irrespective of cisplatin-sensitivity. 5-aza may also have the potential at least to partially restore cisplatin-sensitivity in non-seminoma cells, supporting the hypothesis that combining DNA demethylating agents with cisplatin-based chemotherapy may be a valid therapeutic approach in patients with refractory GCTs.

Oing, C., P. Tennstedt, R. Simon, J. Volquardsen, K. Borgmann, C. Bokemeyer, C. Petersen, E. Dikomey, K. Rothkamm, and W. Y. Mansour, "BCL2-overexpressing prostate cancer cells rely on PARP1-dependent end-joining and are sensitive to combined PARP inhibitor and radiation therapy.", Cancer letters, vol. 423, pp. 60-70, 2018 06 01. Abstract

Here we report that BCL2 blocks DNA double strand break (DSB) repair via nonhomologous end-joining (NHEJ), through sequestration of KU80 protein outside the nucleus. We find that this effect is associated with a repair switch to the error-prone PARP1-dependent end-joining (PARP1-EJ). We present in-vitro proof-of-concept for therapeutic targeting of this switch using PARP inhibitor to specifically enhance the radiosensitivity of BCL2-overexpressing cells. Given its erroneous behavior, PARP1-EJ might allow for the accumulation of genetic alterations and tumor progression. Consistently, we report an inverse correlation between BCL2 expression and biochemical recurrence-free survival of 10.259 prostate cancer (PCa) patients who underwent primary radical-prostatectomy for localized disease. Further, we evaluated retrospectively the impact of BCL2 expression on clinical outcome of 1.426 PCa patients, who had been given salvage radiotherapy at relapse after radical prostatectomy. In line with its role in blocking NHEJ, BCL2 over-expressers showed significantly better response to salvage radiotherapy compared to low-expressers. Collectively, our findings identify BCL2 status in PCa as a putative predictor of (i) radiotherapy response and (ii) response to treatment with PARP inhibitor olaparib as a radiosensitizing agent.

Ojha, N. K., E. Nematian-Ardestani, S. Neugebauer, B. Borowski, D. Ahmed El-Hussein, P. Toshinori Hoshi, D. Enrico Leipold, and D. Stefan H Heinemann, "Sodium channels as gateable non-photonic sensors for membrane-delimited reactive species.", j.bbamem, vol., 2014.
Okasha, H., S. Elkholy, R. Ezzat, and A. El-Kafrawi, "Isolated Pulmonary Valve Vegetations in a Patient with Gastric Lymphoma Diagnosed by Endoscopic Ultrasound", Acta Gastro-Enterologica Belgica, vol. 80, pp. 430-431, 2017.
Okasha, A. E., A. M. El-Refaee, and S. M. Abdelaziz, "Agent-Based Modelling for International Trade", Scientific Journal for Financial and Commercial Studies and Researches (SJFCSR), vol. 3, no. 2: Faculty of Commerce – Damietta University, pp. 585–618, 2022. Abstract
Okasha, H. H., M. - N. Wifi, A. Awad, Y. Abdelfath, D. Abdelfatah, S. S. El‑Sawy, A. Alzamzamy, S. Abou-Elenin, A. Abou‑Elmagd, R. ElHusseiny, et al., "Role of EUS in detection of liver metastasis not seen by computed tomography or magnetic resonance imaging during staging of pancreatic, gastrointestinal, and thoracic malignancies", Endoscopic Ultrasound Journal, vol. 10, issue 5, pp. 344-354, 2021.
Okasha, H., A. M. Abu-Seida, A. A. Hashem, S. E. H. Ashry, and M. M. Nagy, "Inflammatory response and immunohistochemical characterization of experimental calcium silicate-based perforation repair material", International Journal of Experimental Pathology, vol. 103, issue 4, pp. 156-163, 2022. inflammatory_response_of_experimental.pdf
Okasha, T. M., K. S. Anbar, and Y. A. E. S. Seloma, "Cerebral Perfusion Pressure among Acute Traumatic Brain Injury Patients at Supine versus Semi-Fowler Positions", Advances in Life Science and Technologe, 2013. Abstract7576-10147-1-pb.pdf

Background: Positioning is one of the most frequently performed nursing activities in the intensive care units. However literature review documented lack of knowledge about the relationship of cerebral dynamics and different body positions among acute traumatic brain injury patients. Aim: the aim of this study is to assess the effect of supine and semi-fowler position on cerebral perfusion pressure among patients with acute traumatic brain injuries at Cairo University Hospital as indicated by: Glasgow coma score (GCS), arterial blood gases values (ABG), oxygen saturation and vital signs (pulse, blood pressure and respiratory rate). Research questions: What is the effect of supine position on cerebral perfusion pressure among patients with acute traumatic brain injuries? And what is the effect of semi fowler position on cerebral perfusion pressure among patients with acute traumatic brain injuries? Sample: Convenience sample of 39 patients admitted with acute traumatic brain injury. Design: Descriptive exploratory repeated measures study. Setting: University Hospital in Cairo. Tools: Initial acute traumatic brain injury patient’s assessment sheet, and cerebral oxygenation and physiological parameters assessment sheet for acute traumatic brain injury patients. Result: The mean age was 28.5 ±7.9 years. (74.4%) have normal body weight, (25.6%) were having cerebral contusion. Significant increase of CPP, Pao2, SaO2, SPO2, mean arterial pressure and systolic blood pressure, in 15 min post semi-fowler position assessment with a significant decrease of PaCo2. Significant decrease of pulse rate in supine position was evident. With no significant changes in diastolic blood pressure and GCS. Conclusion: Semi-fowler position was found to affect the ABG values, mean arterial pressure, respiratory rate, SpO2 and CPP positively. Recommendation: Studying the effect of side lying and prone position to establish data base about the optimal body position for acute traumatic head injury patients is highly recommended with replication of this study on larger probability sample.

Key words: supine position, semi-fowler position, physiological parameters, cerebral perfusion pressure, acute traumatic brain injury.

Okasha, H. H., M. Gouda, M. Tag-Adeen, M. Farouk, A. Alzamzamy, S. A. Elenin, K. M. Pawlak, A. Awad, and B. Mohamed, Clinical, Radiological, and Endoscopic Ultrasound Findings in Groove Pancreatitis: A Multicenter Retrospective Study, , 2023.
Okasha, H., S. Elkholy, M. Sayed, M. El-Sherbiny, R. El-Hussieny, E. El-Gemeie, W. Al-Nabawy, M. S. Mohamed, and Y. Elsherif, "Ultrasound, endoscopic ultrasound elastography, and the strain ratio in differentiating benign from malignant lymph nodes.", Arab journal of gastroenterology : the official publication of the Pan-Arab Association of Gastroenterology, vol. 19, issue 1, pp. 7-15, 2018. Abstract

BACKGROUND AND STUDY AIMS: Endoscopic ultrasound elastography (EUS-elastography), or sono-elastography, has emerged in the past 2 decades as a qualitative method of estimating tissue stiffness. Strain elastography allows for semi-quantitative measurements of the average elasticity of a lesion, and previous studies have proposed the strain ratio (SR) for overcoming the limitations of the elasticity score. The main objective of this study is to assess the specificity, sensitivity and predictive values of the SR measured by EUS-elastography in differentiating benign from malignant lymph nodes (LNs). This study also aims to find significant ultrasonographic features other than the SR which could help in predicting LN malignancy.

PATIENTS AND METHODS: This prospective study included 126 Egyptian patients with lymphadenopathy. US and EUS-elastography and the SR were assessed, in addition to detailed sonographic features, including size, longest diameter, shortest diameter, ratio of shortest/longest diameter, echotexture (echogenic or echo-poor) and hilum (lost or preserved).

RESULTS: The SR cut-off value of 4.61 showed a sensitivity and specificity of 89.8% and 83.3%, respectively. This parameter had high positive and negative predictive values of 82.5% and 90.2%, respectively, for predicting malignant LNs. Univariate regression analysis showed that echogenicity, hilum preservation, elastography, the shortest dimension, the ratio of the shortest/longest dimension, ultrasound diagnosis and SR could be potential predictors of the final lymph node diagnosis. Sono-diagnosis depending on echogenicity, the shortest/longest diameter ratio and a preserved hilum in combination was the only predictive parameter in multivariate regression analysis.

CONCLUSION: EUS-elastography and the SR could be excellent prognostic indices in differentiating benign from malignant lymph nodes if combined with other US features.

Okasha, H., S. Elkholy, R. El-Sayed, M. - N. Wifi, M. El-Nady, W. El-Nabawi, W. A. El-Dayem, M. I. Radwan, A. L. I. FARAG, Y. El-sherif, et al., "Real time endoscopic ultrasound elastography and strain ratio in the diagnosis of solid pancreatic lesions.", World journal of gastroenterology, vol. 23, issue 32, pp. 5962-5968, 2017. Abstract

AIM: To evaluate the accuracy of the elastography score combined to the strain ratio in the diagnosis of solid pancreatic lesions (SPL).

METHODS: A total of 172 patients with SPL identified by endoscopic ultrasound were enrolled in the study to evaluate the efficacy of elastography and strain ratio in differentiating malignant from benign lesions. The semi quantitative score of elastography was represented by the strain ratio method. Two areas were selected, area (A) representing the region of interest and area (B) representing the normal area. Area (B) was then divided by area (A). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated by comparing diagnoses made by elastography, strain ratio and final diagnoses.

RESULTS: SPL were shown to be benign in 49 patients and malignant in 123 patients. Elastography alone had a sensitivity of 99%, a specificity of 63%, and an accuracy of 88%, a PPV of 87% and an NPV of 96%. The best cut-off level of strain ratio to obtain the maximal area under the curve was 7.8 with a sensitivity of 92%, specificity of 77%, PPV of 91%, NPV of 80% and an accuracy of 88%. Another estimated cut off strain ratio level of 3.8 had a higher sensitivity of 99% and NPV of 96%, but with less specificity, PPV and accuracy 53%, 84% and 86%, respectively. Adding both elastography to strain ratio resulted in a sensitivity of 98%, specificity of 77%, PPV of 91%, NPV of 95% and accuracy of 92% for the diagnosis of SPL.

CONCLUSION: Combining elastography to strain ratio increases the accuracy of the differentiation of benign from malignant SPL.

Okasha, H. H., M. Ashry, H. M. K. Imam, R. E. Mahdy, M. N. Abdalla, A. H. Farag, E. H. Gemeie, and H. M. Khattab, "Role of endoscopic ultrasound-guided fine needle aspiration and ultrasound-guided fine-needle aspiration in diagnosis of cystic pancreatic lesions", Endoscopic Ultrasound Journal, vol. 4, issue 2, pp. 132-136, 2015. role_of_endoscopic_ultrasound-guided_fine_needle.pdf
Okasha, H. H., Y. abdelfattah, O. A. Ashoush, S. Elkholy, R. Singh, R. Abdelghany, S. A. Ahmed, A. E. Salem, A. E. Salem, and A. A. Abdellatif, Role of ultrasound and ultrasound guided fine needle aspiration in diagnosis of peritoneal diseases, , 2020.
Okasha, A., and C. Johnson, "Agent-based computational economics: Studying the effect of different levels of rationality on inflation and unemployment", 2009 IEEE Symposium on Computational Intelligence for Financial Engineering: IEEE, pp. 20–27, 2009. Abstract