Publications by authors named "Annette M Sysel"

The emergence of SARS-CoV-2, the causative agent of COVID-19, highlights the increasing need for new and effective antiviral and antimicrobial agents. The FDA has recently banned several active ingredients used in hand sanitizers, including triclosan and benzethonium chloride. Nitric oxide (NO) is involved in the innate immune response and is a major component of macrophage-mediated attack on foreign viruses and bacteria.

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Cancer cells have an obligate need for cobalamin (vitamin B12) to enable DNA synthesis necessary for cellular replication. This study quantified the immunohistochemical expression of the cobalamin transport protein (transcobalamin II; TCII), cell surface receptor (transcobalamin II-R; TCII-R) and proliferation protein (Ki-67) in naturally occurring canine and feline malignant tumors, and compared these results to expression in corresponding adjacent normal tissues. All malignant tumor tissues stained positively for TCII, TCII-R and Ki-67 proteins; expression varied both within and between tumor types.

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Nitrosylcobalamin (NO-Cbl), a novel vitamin B analog and anti-tumor agent, functions as a biologic 'Trojan horse', utilizing the vitamin B transcobalamin II transport protein and cell surface receptor to specifically target cancer cells. a stability-indicating HPLC method was developed for the detection of NO-Cbl during forced degradation studies. This method utilized an ascentis RP-amide (150 mm × 4.

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Background/aim: Cancer cells have an essential demand for vitamin B12 (cobalamin) to enable cellular replication. The present pilot study quantified the immunohistochemical expression of vitamin B12 transport protein (Transcobalamin II; TCII), cell surface receptor (Transcobalamin II-R; TCII-R) and proliferation protein (Ki-67) in human tumor xenografts.

Materials And Methods: Tissue microarray slides containing 34 xenograft tumor tissues were immunohistochemically stained using TCN2 (anti-TCII), CD320 (anti-TCII-R) and MIB-1 (anti-Ki-67) antibodies.

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Background/aim: Cobalamin and folate are interdependent co-factors of the methionine synthase pathway. This study evaluated the effect of intravenously-administered nitrosylcobalamin (NO-Cbl), a vitamin B12 analog, on serum folate concentrations in healthy dogs.

Materials And Methods: Four dogs received a 10-mg/kg, 20-mg/kg and 40-mg/kg intravenous bolus dose of NO-Cbl, with a 14-day washout period between doses.

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Background/aim: Nitrosylcobalamin (NO-Cbl) is a cobalamin-based anti-tumor agent. This study evaluated the pharmacokinetic parameters of NO-Cbl following intravenous administration in dogs.

Materials And Methods: Four dogs received 10 mg/kg, 20 mg/kg and 40 mg/kg intravenous bolus doses of NO-Cbl, with a 14-day washout period between doses.

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