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1.
Chem Res Toxicol ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703190

RESUMO

Forensic laboratories need quick and simple technology to improve turnaround times, while delivering reliable results. The goal of this study is first to create a simplified workflow to meet new Academy Standards Board requirements for urine testing in drug-facilitated crime investigations and, second, to create "ready-to-go", "hands-free" testing technology to further streamline analytical procedures. A first of its kind, the ToxBox forensic test kit is used to validate a single analytical procedure for opioids, benzodiazepines, cannabinoids, antidepressants, and several other drug classes. Method performance indicators follow accreditation requirements and include accuracy, precision, measurement uncertainty, calibration models, reportable range, sensitivity, specificity, carryover, interference, ion suppression/enhancement, and analyte stability. "Hands-free" testing platforms require the use of new suspended-state technology to stabilize NIST-traceable standards premanufactured at precise concentrations in the presence of sample preparation reagents. By suspending all reaction components in the solid state, with air gaps between the phases, reference standards and process controls are built in a "ready-to-go" format and stabilized for long-term storage in the presence of a sample matrix, ß-d-glucuronidase, and enzymatic buffers. "Hands-free" test kits are removed from storage, incubated at either ambient temperature or 60 °C, and assayed using validated methods. This is the first example of how complex forensic testing workflows can be streamlined with new "hands-free" testing strategies to meet analytical challenges associated with quantitative and confirmatory analyses.

2.
Molecules ; 27(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35956968

RESUMO

(1) Background: New technologies involving gas hydrates under pre-nucleation conditions such as gas separations and storage have become more prominent. This has necessitated the characterization and modeling of the transport properties of such systems. (2) Methodology: This work explored methane hydrate systems under pre-nucleation conditions. All-atom molecular dynamics simulations were used to quantify the performance of the TIP4P/2005 and TIP4P/Ice water models to predict the viscosity, diffusivity, and thermal conductivity using various formulations. (3) Results: Molecular simulation equilibrium was robustly demonstrated using various measures. The Green-Kubo estimation of viscosity outperformed other formulations when combined with TIP4P/Ice, and the same combination outperformed all TIP4P/2005 formulations. The Green-Kubo TIP4P/Ice estimation of viscosity overestimates (by 84% on average) the viscosity of methane hydrate systems under pre-nucleation conditions across all pressures considered (0-5 MPag). The presence of methane was found to increase the average number of hydrogen bonds over time (6.7-7.8%). TIP4P/Ice methane systems were also found to have 16-19% longer hydrogen bond lifetimes over pure water systems. (4) Conclusion: An inherent limitation in the current water force field for its application in the context of transport properties estimations for methane gas hydrate systems. A re-parametrization of the current force field is suggested as a starting point. Until then, this work may serve as a characterization of the deviance in viscosity prediction.

3.
Hepatol Commun ; 6(2): 361-373, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34558847

RESUMO

Current guidelines recommend restricting acetaminophen (APAP) use in patients with cirrhosis, but evidence to support that recommendation is lacking. Prior studies focused on pharmacokinetics (PK) of APAP in cirrhosis but did not rigorously examine clinical outcomes, sensitive biomarkers of liver damage, or serum APAP-protein adducts, which are a specific marker of toxic bioactivation. Hence, the goal of this pilot study was to test the effects of regularly scheduled APAP dosing in a well-defined compensated cirrhosis group compared to control subjects without cirrhosis, using the abovementioned outcomes. After a 2-week washout, 12 subjects with and 12 subjects without cirrhosis received 650 mg APAP twice per day (1.3 g/day) for 4 days, followed by 650 mg on the morning of day 5. Patients were assessed in-person at study initiation (day 1) and on days 3 and 5. APAP-protein adducts and both conventional (alanine aminotransferase) and sensitive (glutamate dehydrogenase [GLDH], full-length keratin 18 [K18], and total high-mobility group box 1 protein) biomarkers of liver injury were measured in serum on the mornings of days 1, 3, and 5, with detailed PK analysis of APAP, metabolites, and APAP-protein adducts throughout day 5. No subject experienced adverse clinical outcomes. GLDH and K18 were significantly different at baseline but did not change in either group during APAP administration. In contrast, clearance of APAP-protein adducts was dramatically delayed in the cirrhosis group. Minor differences for other APAP metabolites were also detected. Conclusion: Short-term administration of low-dose APAP (650 mg twice per day, <1 week) is likely safe in patients with compensated cirrhosis. These data provide a foundation for future studies to test higher doses, longer treatment, and subjects who are decompensated, especially in light of the remarkably delayed adduct clearance in subjects with cirrhosis.


Assuntos
Acetaminofen/administração & dosagem , Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/efeitos adversos , Cirrose Hepática/tratamento farmacológico , Acetaminofen/sangue , Adulto , Alanina Transaminase/sangue , Analgésicos não Narcóticos/sangue , Biomarcadores/sangue , Esquema de Medicação , Feminino , Glutamato Desidrogenase/sangue , Proteína HMGB1/sangue , Humanos , Queratina-18/sangue , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
4.
Biomolecules ; 10(2)2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012744

RESUMO

Several phytochemicals have been identified for their role in modifying miRNA regulating tumor progression. miRNAs modulate the expression of several oncogenes and tumor suppressor genes including the genes that regulate tumor angiogenesis. Hypoxia inducible factor-1 alpha (HIF-1α) signaling is a central axis that activates oncogenic signaling and acts as a metabolic switch in endothelial cell (EC) driven tumor angiogenesis. Tumor angiogenesis driven by metabolic reprogramming of EC is crucial for tumor progression and metastasis in many different cancers, including breast cancers, and has been linked to aberrant miRNA expression profiles. In the current article, we identify different miRNAs that regulate tumor angiogenesis in the context of oncogenic signaling and metabolic reprogramming in ECs and review how selected phytochemicals could modulate miRNA levels to induce an anti-angiogenic action in breast cancer. Studies involving genistein, epigallocatechin gallate (EGCG) and resveratrol demonstrate the regulation of miRNA-21, miRNA-221/222 and miRNA-27, which are prognostic markers in triple negative breast cancers (TNBCs). Modulating the metabolic pathway is a novel strategy for controlling tumor angiogenesis and tumor growth. Cardamonin, curcumin and resveratrol exhibit their anti-angiogenic property by targeting the miRNAs that regulate EC metabolism. Here we suggest that using phytochemicals to target miRNAs, which in turn suppresses tumor angiogenesis, should have the potential to inhibit tumor growth, progression, invasion and metastasis and may be developed into an effective therapeutic strategy for the treatment of many different cancers where tumor angiogenesis plays a significant role in tumor growth and progression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Neovascularização Patológica , Inibidores da Angiogênese/farmacologia , Neoplasias da Mama/metabolismo , Chalconas/farmacologia , Curcumina/farmacologia , Progressão da Doença , Células Endoteliais/metabolismo , Feminino , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Oxigênio/metabolismo , Compostos Fitoquímicos , Fitoterapia , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/farmacologia , Transdução de Sinais
5.
Cancers (Basel) ; 11(11)2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31698699

RESUMO

Metformin, the most widely used anti-diabetic drug, also exhibits anti-cancer properties; however, the true potential of metformin as an anticancer drug remains largely unknown. In this study using mouse microvascular endothelial cells (MMECs), we investigated the effects of metformin alone or in combination with the glycolytic inhibitor, 2-deoxyglucose (2DG), on angiogenesis-a process known to be an integral part of tumor growth, cancer cell survival and metastasis. MMECs were exposed to 2DG (1-10 mM) for 48 h in the absence or presence of metformin (2 mM). The status of angiogenic and anti-angiogenic marker proteins, proteins of the mTOR pathway and cell-cycle-related proteins were quantified by Western blot analysis. Assays for cell proliferation, migration and tubulogenesis were also performed. We observed robust up-regulation of anti-angiogenic thrombospondin-1 (TSP1) and increased TSP1-CD36 co-localization with a marked decrease in the levels of phosphorylated vascular endothelial growth factor receptor-2 (pVEGFR2; Y1175) in 2DG (5 mM) exposed cells treated with metformin (2 mM). Additionally, treatment with metformin and 2DG (5 mM) inhibited the Akt/mTOR pathway and down-regulated the cell-cycle-related proteins such as p-cyclin B1 (S147) and cyclins D1 and D2 when compared to cells that were treated with either 2DG or metformin alone. Treatment with a combination of 2DG (5 mM) and metformin (2 mM) also significantly decreased cell proliferation, migration and tubulogenic capacity when compared to cells that were treated with either 2DG or metformin alone. The up-regulation of TSP1, inhibition of cell proliferation, migration and tubulogenesis provides support to the argument that the combination of metformin and 2DG may prove to be an appropriate anti-proliferative and anti-angiogenic therapeutic strategy for the treatment of some cancers.

6.
J Emerg Manag ; 15(3): 189-194, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28829531

RESUMO

OBJECTIVE: To examine the relationship between social capital and potential resilience at the individual level from the perspective of emergency management. METHODS: The authors used an online survey tool to present various scales of measurement related to the variables of social capital and potential resilience. RESULTS: It was predicted that social capital and demographics, such as income, would be positively related to potential resilience. Overall, results indicated that income (ß = 0.33, p < 0.01) and social capital (ß = 0.32, p < 0.01) were both significant predictors of potential resilience. Implications and future directions for research and practices are discussed.


Assuntos
Renda , Resiliência Psicológica , Capital Social , Planejamento em Desastres , Desastres , Florida , Humanos , Modelos Lineares , Inquéritos e Questionários
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