Publications by authors named "R M Samir"

In this paper, we re-estimate the astrometric and photometric parameters of the young open star cluster King 18 based on Gaia Data Release 3 (DR3), Two Micron All-sky Survey (2MASS) and VRI CCD observations using the f/4.9 Newtonian focus of 74-inch telescope at Kottamia Astronomical Observatory (KAO) in Egypt. King 18 is a poorly studied open star cluster, for which new results are found in the current study.

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Sympathetic activation triggered by chronic stress afflicting cancer survivors is an emerging modulator of tumorigenesis. Adrenergic blockade was previously associated with improving response to doxorubicin (DOX) in triple-negative breast cancer (TNBC), yet the precise underlying mechanisms remain obscure. The resilience of cancer stem cells (CSCs) during chemotherapy fosters resistance and relapse.

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Background: The Coronavirus disease 2019 (COVID-19) pandemic has robustly affected the global healthcare and economic systems and it was caused by coronavirus-2 (SARS-CoV-2). The clinical presentation of the disease ranges from a flu-like illness to severe pneumonia and death. Till September 2022, the cumulative number of cases exceeded 600 million worldwide and deaths were more than 6 million.

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The recent COVID-19 pandemic shows the critical need for novel broad spectrum antiviral agents. Scorpion venoms are known to contain highly bioactive peptides, several of which have demonstrated strong antiviral activity against a range of viruses. We have generated the first annotated reference transcriptome for the Androctonus amoreuxi venom gland and used high performance liquid chromatography, transcriptome mining, circular dichroism and mass spectrometric analysis to purify and characterize twelve previously undescribed venom peptides.

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Background: Bacterial ghost cells (BGCs) are cells were drained of their genetic and cytoplasmic components. This work aimed to develop vaccine candidates against the Shigella flexneri (S. flexneri) 2b serotype using the BGCs approach.

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