Publications by authors named "Alexander Lyubimov"

Cirrhosis is a liver disease that leads to increased intrahepatic resistance, portal hypertension (PH), and splanchnic hyperemia resulting in ascites, variceal bleeding, and hepatorenal syndrome. Terlipressin, a prodrug that converts to a short half-life vasopressin receptor 1 A (V1a) full agonist [8-Lys]-Vasopressin (LVP), is an intravenous treatment for PH complications, but hyponatremia and ischemic side effects require close monitoring. We developed PHIN-214 which converts into PHIN-156, a more biologically stable V1a partial agonist.

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Introduction: Cannabinoids are increasingly popular in human and veterinary medicine and have been studied as an alternative treatment for a wide range of disorders. The goal of this study was to perform a pharmacokinetic analysis of oral cannabidiol (CBD)-/cannabidiolic acid (CBDA)-rich hemp oil (CBD/ArHO) in juvenile cynomolgus macaques ().

Methods: After a 2 mg/kg CBD/ArHO pilot study, 4 and 8 mg/kg direct-to-mouth CBD/ArHO were administered ( = 4 per dose) once daily for 14 days and blood was collected at 0-, 0.

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Spectral-luminescence properties of a hybrid compound containing a coumarin-type spiropyran and an azomethinocoumarin fragment in toluene-acetonitrile solution in the presence of Li, Ca, Zn and Mg ions are reported. Two excited state proton transfers can occur in the hybrid compound-the transfer of a proton from the OH group of the 7-hydroxy coumarin tautomer to the N atom of the C=N bond of the azomethine fragment leading to green ESIPT fluorescence with a maximum at 540 nm and from the OH group of the 7-hydroxy coumarin tautomer to the carbonyl group of the pyrone chromophore, which leads to the formation of the 2-hydroxyl-tautomer of coumarin with blue fluorescence with a maximum at 475 nm. Dependence of these excited state proton transfers on the metal nature and irradiation with an external UV source is discussed.

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Purpose: Animal models that accurately reflect human responses to radiation injury are needed for advanced mechanistic investigation and development of effective therapeutics. The rabbit is an established animal model accepted by the FDA for studies of cardiovascular disease, lipid metabolism, the development of anticoagulants, testing of bone implants, and the development of treatments for infectious diseases such as HIV. The purpose of this study was to investigate the New Zealand White (NZW) Rabbit model as a model of acute radiation exposure because of its established similarity to human vascular, immune, and coagulation responses.

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Brodifacoum (BDF) is a potent, long-acting anticoagulant rodenticide that can cause fatal poisoning in humans. The chemical structure of BDF includes 2 chiral carbons, resulting in 2 pairs of diastereomers, BDF-cis (R/S and S/R) and BDF-trans (R/R and S/S). However, the relative potency of these molecules is not known.

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There is an unmet need for the treatment of glioblastoma multiforme (GBM). The extracellular matrix, including laminins, in the tumor microenvironment is important for tumor invasion and progression. In a panel of 226 patient brain glioma samples, we found a clinical correlation between the expression of tumor vascular laminin-411 (α4β1γ1) with higher tumor grade and with expression of cancer stem cell (CSC) markers, including Notch pathway members, CD133, Nestin, and c-Myc.

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Patients exposed to long acting anticoagulant rodenticides (LAARs) are typically administered large amounts of oral vitamin K1 (VK1) to counteract life-threatening anticoagulant effects. Although VK1 treatment effectively prevents mortality, additional methods are needed to reduce the long duration of VK1 treatment which can last for months at high expense. We developed a model of brodifacoum (BDF) poisoning, one of the most potent LAARs, in adult male New Zealand White (NZW) rabbits.

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Acute lymphoblastic leukemia (ALL) is the most common type of pediatric cancer, although about 4 of every 10 cases occur in adults. The enzyme drug l-asparaginase serves as a cornerstone of ALL therapy and exploits the asparagine dependency of ALL cells. In addition to hydrolyzing the amino acid l-asparagine, all FDA-approved l-asparaginases also have significant l-glutaminase coactivity.

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The FoxA family of pioneer transcription factors regulates hepatitis B virus (HBV) transcription, and hence viral replication. Hepatocyte-specific FoxA-deficiency in the HBV transgenic mouse model of chronic infection prevents the transcription of the viral DNA genome as a result of the failure of the developmentally controlled conversion of 5-methylcytosine residues to cytosine during postnatal hepatic maturation. These observations suggest that pioneer transcription factors such as FoxA, which mark genes for expression at subsequent developmental steps in the cellular differentiation program, mediate their effects by reversing the DNA methylation status of their target genes to permit their ensuing expression when the appropriate tissue-specific transcription factor combinations arise during development.

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We evaluated the mitigating effects of fibroblast growth factor 4 and 7 (FGF4 and FGF7, respectively) in comparison with long acting protected graft copolymer (PGC)-formulated FGF4 and 7 (PF4 and PF7, respectively) administered to C57BL/6J mice a day after exposure to LD50/30 (15.7 Gy) partial body irradiation (PBI) which targeted the gastrointestinal (GI) system. The PGC that we developed increased the bioavailability of FGF4 and FGF7 by 5- and 250-fold compared to without PGC, respectively, and also sustained a 24 hr presence in the blood after a single subcutaneous administration.

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Neuroblastoma is the most common extracranial childhood solid tumor. Treatment of high risk tumors require intense multicycle chemotherapies, resulting in short- and long-term toxicities. Here, we present treatment of an orthotopic neuroblastoma mouse model, with silk fibroin materials loaded with vincristine, doxorubicin or the combination as a intratumoral, sustained release system.

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Total body irradiation of mice is a commonly used research technique; however, humane endpoints have not been clearly identified. This situation has led to the inconsistent use of various endpoints, including death. To address this issue, we refined a cageside observation-based scoring system specifically for mice receiving total body irradiated.

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Objective: Poor prognosis of sepsis is associated with bacterial lipopolysaccharide (LPS)-induced intravascular inflammation, microvascular thrombosis, thrombocytopenia, and disseminated intravascular coagulation. Platelets are critical for thrombosis, and there has been increasing evidence of the importance of platelets in endotoxemia. The platelet adhesion receptor, the glycoprotein Ib-IX complex (GPIb-IX), mediates platelet adhesion to inflammatory vascular endothelium and exposed subendothelium.

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Purpose: Our objective was to develop novel nanocarriers (protected graft copolymer, PGC) that improve the stability of heparin binding EGF (HBEGF) and gastrin and then to use PGC-formulated HBEGF (PGC-HBEGF) and Omeprazole (+/- PGC-gastrin) for normalizing fasting blood glucose (FBG) and improving islet function in diabetic mice.

Methods: HBEGF, PGC-HBEGF, Omeprazole, Omeprazole + PGC-HBEGF, Omeprazole + PGC-gastrin + PGC-HBEGF and epidermal growth factor (EGF) + gastrin were tested in multiple low dose streptozotocin diabetic mice.

Results: Omeprazole + PGC-HBEGF normalized FBG and is better than EGF + gastrin at improving islet function and decreasing insulitis.

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Potency and activity of SR13668 in cancer prevention have been proven in several in vitro and in vivo cancer models. However, the compound is highly hydrophobic and its limited oral bioavailability has hindered its clinical translation. In this study, we encapsulated SR13668 into polymeric nanoparticles to increase compound aqueous solubility and therefore bioavailability.

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SHetA2 is a heteroarotinoid that has shown selective inhibition of cancer cell growth and an induction of apoptosis without activation of nuclear retinoic acid receptors. In the rat study, SHetA2 was administered in 1% aqueous methylcellulose/0.2% Tween 80 by oral gavage at 0, 100, 500, and 2,000 mg/kg/day for 28 days.

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Nanoparticle-encapsulated thiazole antibiotic, thiostrepton, has been shown to be an effective agent for inhibiting tumor growth in solid tumor models through the inhibition of proteasomal activity by the induction of apoptosis in cancer cells. Here, we show the efficacy of thiostrepton-micelles in inhibiting tumor growth in a DEN/PB-induced liver cancer model. We also demonstrate an enhanced anticancer effect of the combination treatment of thiostrepton with bortezomib, another proteasome inhibitor in this liver cancer model.

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SR13668 [2,10-Dicarbethoxy-6-methoxy-5,7-dihydro-indolo-(2,3-b)carbazole] has been proven effective in cancer prevention, but the limited bioavailability has hindered its clinical translation. In this study, we have developed a continuous, scalable process to form stable poly(lactic-co-glycolic acid) nanoparticles encapsulating SR13668, based on understanding of the competitive kinetics of nanoprecipitation and spray drying. The optimized formulation achieved high drug loading (33.

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2-Chloro-5-nitro-N-phenylbenzamide (GW9662), a potent irreversible PPAR-γ antagonist, has shown promise as a cancer chemopreventive agent and is undergoing preclinical evaluations. Studies were initiated to assess its bacterial mutagenicity and pharmacokinetic profile in two animal species prior to subchronic oral toxicity evaluations and the results are reported here. GW9662 was mutagenic in both TA98 and TA100 bacterial strains with and without metabolic activation but was negative in the nitroreductase-deficient strains (TA98NR and TA100NR) also with and without metabolic activation, indicating that GW9662 mutagenicity is dependent on nitroreduction.

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Purpose: To develop a long-acting formulation of native human insulin with a similar pharmacodynamics (PD) profile as the insulin analogue insulin glargine (Lantus®, Sanofi-Aventis) with the expectation of retaining native human insulin's superior safety profile as insulin glargine is able to activate the insulin-like growth factor 1 (IGF-1) receptor and is linked to a number of malignancies at a higher rate than regular human insulin.

Methods: Development of protected graft copolymer (PGC) excipients that bind native human insulin non-covalently and testing blood glucose control obtained with these formulations in streptozotocin-induced diabetic Sprague Dawley rats compared to equally dosed insulin glargine.

Results: PGC-formulations of native human insulin are able to control blood glucose to the same extent and for the same amount of time after s.

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9-cis-UAB30 is a potential chemopreventative agent that has been shown to be effective on many different types of tumors. The safety and toxicity of 9-cis-UAB30 had not been previously established. These studies were conducted to evaluate the potential toxicity and pharmacokinetics in a rodent and a nonrodent species for the purpose of investigational new drug submission.

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2,2,5,7,8-Pentamethyl-6-chromanol (PMCol) was administered by gavage in rats for 28 days at dose levels of 0, 100, 500, and 2000mg/kg/day. PMCol administration induced decreases in body weight gains and food consumption, hepatotoxicity (increased TBILI, ALB, ALT, TP; increased relative liver weights; increased T4 and TSH), nephrotoxicity (increased BUN and BUN/CREAT, histopathology lesions), effect on lipid metabolism (increased CHOL), anemia, increase in WBC counts (total and differential), coagulation (FBGN upward arrow and PT downward arrow) and hyperkeratosis of the nonglandular stomach in the 2000mg/kg/day dose group (in one or both sexes). In the 500mg/kg/day dose group, toxicity was seen to a lesser extent.

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The purpose of this work was to compare the pharmacokinetics (PK) and tissue distribution of [14C]fluasterone following intravenous (iv), subcutaneous (sc) and oral (po) administration in male Beagle dogs. The main goal of the investigation was to discover if non-oral routes would alter parameters observed in this study following the administration of [14C]fluasterone. The oral formulation had a lower bioavailability (47%) compared to the sc formulation (84%).

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The objective of this research was the identification of the metabolic profile of fluasterone, a synthetic derivative of dehydroepiandrosterone, in dogs treated orally or subcutaneously with [4-(14)C]fluasterone. Separation and characterization techniques used to identify the principal metabolites of fluasterone in urine and feces included high-performance liquid chromatography (HPLC), liquid scintillation spectrometry, HPLC/tandem mass spectrometry, and NMR. In urine, the majority of the radioactivity was present as two components that had apparent molecular weights consistent with their tentative identification as monoglucuronide conjugates of 4alpha-hydroxy-16alpha-fluoro-5-androsten-17beta-ol and X(alpha or beta)-4alpha-dihydroxy-16alpha-fluoro-5-androsten-17beta-ol.

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Several compounds, including 2,10-dicarbethoxy-6-methoxy-5,7-dihydroindolo[2,3-b]carbazole (SR13668), (2E,4E,6Z,8E)-8-(3',4'-dihydro-1'(2'H)-napthalen-1'-ylidene)-3,7-dimethyl-2,4,6-octatrienoic acid (9-cis-UAB30), and 2,2,5,7,8-pentamethyl-6-chromanol (PMCol), were selected as promising chemopreventive agents and have entered preclinical trials for cancer prevention. The potential for adverse drug events resulting from interactions with other administered drugs, food components, or food additives presents an important question. Among the most important drug-drug interactions (DDI) is the potential of a new chemical entity (NCE) to induce cytochrome P450 enzymes (P450).

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