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- 저자 : Hassan Ahmed (검색결과 199 건)
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Hassan Ahmed Hassan Ahmed Ismail,강병훈,김재수,이재형,최인욱,차광호,육재민,이영하 대한기생충학ㆍ열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.6
IL-12 and IL-23 are closely related in structure, and have been shown to play crucial roles in regulation of immune responses. However, little is known about the regulation of these cytokines in T cells. Here, we investigated the roles of PI3K and MAPK pathways in IL-12 and IL-23 production in human Jurkat T cells in response to Toxoplasma gondii and LPS. IL-12 and IL-23 production was significantly increased in T cells after stimulation with T. gondii or LPS. T. gondii and LPS increased the phosphorylation of AKT, ERK1/2, p38 MAPK, and JNK1/2 in T cells from 10 min post-stimulation, and peaked at 30-60 min. Inhibition of the PI3K pathway reduced IL-12 and IL-23 production in T. gondii-infected cells, but increased in LPS-stimulated cells. IL-12 and IL-23 production was significantly reduced by ERK1/2 and p38 MAPK inhibitors in T. gondii- and LPS-stimulated cells, but not in cells treated with a JNK1/2 inhibitor. Collectively, IL-12 and IL-23 production was positively regulated by PI3K and JNK1/2 in T. gondii-infected Jurkat cells, but negatively regulated in LPS-stimulated cells. And ERK1/2 and p38 MAPK positively regulated IL-12 and IL-23 production in Jurkat T cells. These data indicate that T. gondii and LPS induced IL-12 and IL-23 production in Jurkat T cells through the regulation of the PI3K and MAPK pathways; however, the mechanism underlying the stimulation of IL-12 and IL-23 production by T. gondii in Jurkat T cells is different from that of LPS.
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Ismail Hassan Ahmed Hassan Ahmed,차승만,김연,홍성태 대한기생충학ㆍ열대의학회 2023 The Korean Journal of Parasitology Vol.61 No.2
In several schistosomiasis-endemic countries, the prevalence has remained high in some areas owing to reinfection despite repeated mass drug administration (MDA) interventions; these areas are referred to as persistent hot spots. Identifying hotspots is critical for interrupting transmission. This study aimed to determine an effective means of identifying persistent hot spots. First, we investigated the differences between Schistosoma haematobium and Schistosoma mansoni prevalence among school-aged children (SAC) estimated by a community-based survey, for which local key informants purposively selected communities, and a randomly sampled school-based survey. A total of 6,225 individuals residing in 60 villages in 8 districts of North Kordofan, Blue Nile, or Sennar States, Sudan participated in a community-based survey in March 2018. Additionally, the data of 3,959 students attending 71 schools in the same 8 districts were extracted from a nationwide school-based survey conducted in January 2017. The community-based survey identified 3 districts wherein the prevalence of S. haematobium or S. mansoni infection among SAC was significantly higher than that determined by the randomly sampled school survey (e.g., S. haematobium in the Sennar district: 10.8% vs. 1.1%, P<0.001). At the state level, the prevalence of schistosomiasis among SAC, as determined by the community-based survey, was consistently significantly higher than that determined by the school-based survey. Purposeful selection of villages or schools based on a history of MDA, latrine coverage, open defecation, and the prevalence of bloody urine improved the ability for identifying persistent hot spots.
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Ahmed, Hanaa H,Abd-Rabou, Ahmed A,Hassan, Amal Z,Kotob, Soheir E Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16
Cancer is a major health obstacle around the world, with hepatocellular carcinoma (HCC) and colorectal cancer (CRC) as major causes of morbidity and mortality. Nowadays, there isgrowing interest in the therapeutic use of natural products for HCC and CRC, owing to the anticancer activity of their bioactive constituents. Boswellia serrata oleo gum resin has long been used in Ayurvedic and traditional Chinese medicine to alleviate a variety of health problems such as inflammatory and arthritic diseases. The current study aimed to identify and explore the in vitro anticancer effect of B. Serrata bioactive constituents on HepG2 and HCT 116 cell lines. Phytochemical analysis of volatile oils of B. Serrata oleo gum resin was carried out using gas chromatography-mass spectrometry (GC/MS). Oleo-gum-resin of B. Serrata was then successively extracted with petroleum ether (extract 1) and methanol (extract 2). Gas-liquid chromatography (GLC) analysis of the lipoidal matter was also performed. In addition, a methanol extract of B. Serrata oleo gum resin was phytochemically studied using column chromatography (CC) and thin layer chromatography (TLC) to obtain four fractions (I, II, III and IV). Sephadex columns were used to isolate ${\beta}$-boswellic acid and identification of the pure compound was done using UV, mass spectra, $^1H$ NMR and $^{13}C$ NMR analysis. Total extracts, fractions and volatile oils of B. Serrata oleo-gum resin were subsequently applied to HCC cells (HepG2 cell line) and CRC cells (HCT 116 cell line) to assess their cytotoxic effects. GLC analysis of the lipoidal matter resulted in identification of tricosane (75.32%) as a major compound with the presence of cholesterol, stigmasterol and ${\beta}$-sitosterol. Twenty two fatty acids were identified of which saturated fatty acids represented 25.6% and unsaturated fatty acids 74.4% of the total saponifiable fraction. GC/MS analysis of three chromatographic fractions (I,II and III) of B. Serrata oleo gum resin revealed the presence of pent-2-ene-1,4-dione, 2-methyl- levulinic acid methyl ester, 3,5- dimethyl- 1-hexane, methyl-1-methylpentadecanoate, 1,1- dimethoxy cyclohexane, 1-methoxy-4-(1-propenyl)benzene and 17a-hydroxy-17a-cyano, preg-4-en-3-one. GC/MS analysis of volatile oils of B. Serrata oleo gum resin revealed the presence of sabinene (19.11%), terpinen-4-ol (14.64%) and terpinyl acetate (13.01%) as major constituents. The anti-cancer effect of two extracts (1 and 2) and four fractions (I, II, III and IV) as well as volatile oils of B. Serrata oleo gum resin on HepG2 and HCT 116 cell lines was investigated using SRB assay. Regarding HepG2 cell line, extracts 1 and 2 elicited the most pronounced cytotoxic activity with $IC_{50}$ values equal 1.58 and $5.82{\mu}g/mL$ at 48 h, respectively which were comparable to doxorubicin with an $IC_{50}$ equal $4.68{\mu}g/mL$ at 48 h. With respect to HCT 116 cells, extracts 1 and 2 exhibited the most obvious cytotoxic effect; with $IC_{50}$ values equal 0.12 and $6.59{\mu}g/mL$ at 48 h, respectively which were comparable to 5-fluorouracil with an $IC_{50}$ equal $3.43{\mu}g/mL$ at 48 h. In conclusion, total extracts, fractions and volatile oils of B. Serrata oleo gum resin proved their usefulness as cytotoxic mediators against HepG2 and HCT 116 cell lines with different potentiality (extracts > fractions > volatile oil). In the two studied cell lines the cytotoxic acivity of each of extract 1 and 2 was comparable to doxorubicin and 5-fluorouracil, respectively. Extensive in vivo research is warranted to explore the precise molecular mechanisms of these bioactive natural products in cytotoxicity against HCC and CRC cells.
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Hassan, Ahmed H.E.,Choi, Eunwoo,Yoon, Yoon Mi,Lee, Kun Won,Yoo, Sung Yeun,Cho, Min Chang,Yang, Ji Seul,Kim, Hye In,Hong, Joo Young,Shin, Ji-Sun,Chung, Kyung-Sook,Lee, Jeong-Hun,Lee, Kyung-Tae,Lee, Yon Elsevier 2019 European journal of medicinal chemistry Vol.161 No.-
<P><B>Abstract</B></P> <P>Cancer still represents a major global health problem. All currently available anticancer agents have disadvantages like resistance or side effects. Therefore, introduction of novel anticancer agents is needed. Intrigued by the high success rate for natural products-based drug discovery, we designed and synthesized antiproliferative chemical entities as hybrids of two natural products; 3,5,4′-trimethoxystilbene and 5,6,7-trimethoxyflavone. To probe the spectrum of the synthesized compounds, <I>in vitro</I> evaluation was conducted against nine panels representing major cancer diseases. The results revealed the hybrid analogs <B>4f</B>, <B>4h</B>, <B>4k</B> and <B>4q</B> as promising broad-spectrum anticancer lead compounds eliciting high growth inhibition of several cell lines representing multiple cancers diseases. Evaluation of the promising lead compounds against normal human cell lines suggested a selective cytotoxic effect on cancer cells. Mechanistic investigation of the cytotoxic activity of compound <B>4f</B> in human cervical cancer HeLa cells showed that it triggers cell death through induction of apoptosis. As a whole, this study presents the natural products hybrid analogs <B>4f</B>, <B>4h</B>, <B>4k</B> and <B>4q</B> as potential lead compounds for further development of novel anticancer therapeutics.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Design, synthesis and <I>in vitro</I> antiproliferative evaluation of 3,5,4′-trimethoxystilbene-5,6,7-trimethoxyflavone hybrids. </LI> <LI> Compounds <B>4f</B>, <B>4h</B>, <B>4k</B> and <B>4q</B> elicited promising broad spectrum antiproliferative activity. </LI> <LI> Compounds <B>4f</B>, <B>4h</B>, <B>4k</B> and <B>4q</B> were more selective to human cancer cells rather than normal human cells. </LI> <LI> Compound <B>4f</B> triggered cell death via induction of apoptosis in HeLa cells. </LI> <LI> Compounds <B>4f</B>, <B>4h</B>, <B>4k</B> and <B>4q</B> might be potential leads for development of natural-products based anticancer agents. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
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RUFS: RobUst Forwarder Selection in Vehicular Content-Centric Networks
Ahmed, Syed Hassan,Bouk, Safdar Hussain,Dongkyun Kim IEEE 2015 IEEE communications letters Vol.19 No.9
<P>Vehicular Content-Centric Network (VCCN) has emerged as a future network technology for vehicular networks, where the focus of communication is shifted from the host to information centric. However, VCCN faces several challenges, including interest/data packet(s) flooding, provider/consumer mobility, and so on. In this letter, we propose a scheme named RobUst Forwarder Selection (RUFS) to mitigate the interest broadcast storm. In RUFS, each vehicle shares its satisfied interest(s) statistics with neighbors. All neighbors store this information in their Neighbors Satisfied List (NSL), which helps to select the potential interest forwarder. Simulation results show that RUFS outperforms the recently proposed NAIF, DR based and basic interest forwarding in VCCN.</P>
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Hassan, Ahmed H. E.,Lee, Jae Kyun,Pae, Ae Nim,Min, Sun-Joon,Cho, Yong Seo American Chemical Society 2015 ORGANIC LETTERS Vol.17 No.11
<P>A synthetic approach toward the tricyclic 5,7,6-membered ring structure Of daphnane-family natural products is described. An intramolecular [4 + 3] cycloaddition reaction of furan with an oxypentadienyl cation constructed the oxa-bridged bicyclic structure in a stereoselective fashion. Structural analysis revealed that the desired exo isomer was predominantly acquired through epimerization. Finally, formation of the five-membered ring was achieved through SmI2-mediated pinacol coupling.</P>
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Hassan Aboul-Nour,Ahmed Maraey,Ammar Jumah,Mahmoud Khalil,Ahmed M. Elzanaty,Hadeer Elsharn,Fawaz Al-Mufti,Alex Bou Chebl,Daniel J. Miller,Stephan A. Mayer 대한뇌졸중학회 2023 Journal of stroke Vol.25 No.1
Background and Purpose Mechanical thrombectomy (MT) is the standard treatment for large vessel occlusion (LVO) acute ischemic stroke. Patients with active malignancy have an increased risk of stroke but were excluded from MT trials. Methods We searched the National Readmission Database for LVO patients treated with MT between 2016–2018 and compared the characteristics and outcomes of cancer-free patients to those with metastatic cancer (MC). Primary outcomes were all-cause in-hospital mortality and favorable outcome, defined as a routine discharge to home (regardless of whether home services were provided or not). Multivariate regression was used to adjust for confounders. Results Of 40,537 LVO patients treated with MT, 933 (2.3%) had MC diagnosis. Compared to cancer-free patients, MC patients were similar in age and stroke severity but had greater overall disease severity. Hospital complications that occurred more frequently in MC included pneumonia, sepsis, acute coronary syndrome, deep vein thrombosis, and pulmonary embolism (P<0.001). Patients with MC had similar rates of intracerebral hemorrhage (20% vs. 21%) but were less likely to receive tissue plasminogen activator (13% vs. 23%, P<0.001). In unadjusted analysis, MC patients as compared to cancer-free patients had a higher in-hospital mortality rate and were less likely to be discharged to home (36% vs. 42%, P=0.014). On multivariate regression adjusting for confounders, mortality was the only outcome that was significantly higher in the MC group than in the cancerfree group (P<0.001). Conclusion LVO patients with MC have higher mortality and more infectious and thrombotic complications than cancer-free patients. MT nonetheless can result in survival with good outcome in slightly over one-third of patients.
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Numerical Study of Fan Coil Heat Exchanger with Copper-Foam
Ahmed M. Hassan,Adil Abbas Alwan,Hameed K. Hamzah 한국유체기계학회 2023 International journal of fluid machinery and syste Vol.16 No.1
Due to its high porosity as well as a high specific surface area, the use of open cell metallic foam in heat transfer applications has received increasing interest. In present study, the dynamic and thermal performance of heat exchanger composed of copper foam incorporated in a fan coil was numerically analyzed. Darcy-Brinkman-Forchheimer model was used to represent the momentum equation inside the metallic foam (a porous medium). A local thermal equilibrium was used to solve the energy equation through the porous medium. Different porosity values were taken during the study, ranging from 0.88 to 0.98, while the velocity of inlet air of the heat exchanger ranged from 1 m/s to 10 m/s. The objective of current study is to compare the thermal and dynamic performance of the heat exchanger affected by several variables such as heat transfer coefficient, friction factor, pressure drop, Colburn factor, and area goodness factor. The results showed that increasing the air inlet velocity will increase the heat transfer coefficient, but on the other hand, increasing the velocity ten times will rise pressure drop from 19.032 Pa to 335.76 Pa. Also, the area goodness factor value will decrease with increasing inlet velocity. Finally, we found that increasing in medium porosity will reduce heat transfer coefficient but increase pressure drop
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