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1.
Drug Metab Dispos ; 52(4): 312-321, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38307853

RESUMO

Humans are chronically exposed to benzalkonium chlorides (BACs) from environmental sources. The U.S. Food and Drug Administration (FDA) has recently called for additional BAC safety data, as these compounds are cytotoxic and have great potential for biochemical interactions. Biodistribution studies revealed that BACs extensively distribute to many tissues and accumulate at high levels, especially in the kidneys, but the underlying mechanisms are unclear. In this study, we characterized the interactions of BACs of varying alkyl chain length (C8 to C14) with the human organic cation transporters (hOCT1-3) and multidrug and toxin extrusion proteins (hMATE1/2K) with the goal to identify transporters that could be involved in BAC disposition. Using transporter-expressing cell lines, we showed that all BACs are inhibitors of hOCT1-3 and hMATE1/2K (IC50 ranging 0.83-25.8 µM). Further, the short-chain BACs (C8 and C10) were identified as substrates of these transporters. Interestingly, although BAC C8 displayed typical Michaelis-Menten kinetics, C10 demonstrated a more complex substrate-inhibition profile. Transwell studies with transfected Madin-Darby canine kidney cells revealed that intracellular accumulation of basally applied BAC C8 and C10 was substantially higher (8.2- and 3.7-fold, respectively) in hOCT2/hMATE1 double-transfected cells in comparison with vector-transfected cells, supporting a role of these transporters in mediating renal accumulation of these compounds in vivo. Together, our results suggest that BACs interact with hOCT1-3 and hMATE1/2K as both inhibitors and substrates and that these transporters may play important roles in tissue-specific accumulation and potential toxicity of short-chain BACs. Our findings have important implications for understanding human exposure and susceptibility to BACs due to environmental exposure. SIGNIFICANCE STATEMENT: Humans are systemically exposed to benzalkonium chlorides (BACs). These compounds broadly distribute through tissues, and their safety has been questioned by the FDA. Our results demonstrate that hOCT2 and hMATE1 contribute to the renal accumulation of BAC C8 and C10 and that hOCT1 and hOCT3 may be involved in the tissue distribution of these compounds. These findings can improve our understanding of BAC disposition and toxicology in humans, as their accumulation could lead to biochemical interactions and deleterious effects.


Assuntos
Compostos de Benzalcônio , Proteínas de Transporte de Cátions Orgânicos , Animais , Cães , Humanos , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Distribuição Tecidual , Linhagem Celular , Células Madin Darby de Rim Canino , Transportador 2 de Cátion Orgânico/metabolismo
2.
Environ Sci Technol ; 58(14): 6236-6249, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38534032

RESUMO

The COVID-19 pandemic has led to significantly increased human exposure to the widely used disinfectants quaternary ammonium compounds (QACs). Xenobiotic metabolism serves a critical role in the clearance of environmental molecules, yet limited data are available on the routes of QAC metabolism or metabolite levels in humans. To address this gap and to advance QAC biomonitoring capabilities, we analyzed 19 commonly used QACs and their phase I metabolites by liquid chromatography-ion mobility-tandem mass spectrometry (LC-IM-MS/MS). In vitro generation of QAC metabolites by human liver microsomes produced a series of oxidized metabolites, with metabolism generally occurring on the alkyl chain group, as supported by MS/MS fragmentation. Discernible trends were observed in the gas-phase IM behavior of QAC metabolites, which, despite their increased mass, displayed smaller collision cross-section (CCS) values than those of their respective parent compounds. We then constructed a multidimensional reference SQLite database consisting of m/z, CCS, retention time (rt), and MS/MS spectra for 19 parent QACs and 81 QAC metabolites. Using this database, we confidently identified 13 parent QACs and 35 metabolites in de-identified human fecal samples. This is the first study to integrate in vitro metabolite biosynthesis with LC-IM-MS/MS for the simultaneous monitoring of parent QACs and their metabolites in humans.


Assuntos
Desinfetantes , Compostos de Amônio Quaternário , Humanos , Compostos de Amônio Quaternário/análise , Compostos de Amônio Quaternário/química , Espectrometria de Massas em Tandem/métodos , Pandemias , Cromatografia Líquida , Fígado
3.
Environ Sci Technol ; 57(20): 7645-7665, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37157132

RESUMO

Quaternary ammonium compounds (QACs), a large class of chemicals that includes high production volume substances, have been used for decades as antimicrobials, preservatives, and antistatic agents and for other functions in cleaning, disinfecting, personal care products, and durable consumer goods. QAC use has accelerated in response to the COVID-19 pandemic and the banning of 19 antimicrobials from several personal care products by the US Food and Drug Administration in 2016. Studies conducted before and after the onset of the pandemic indicate increased human exposure to QACs. Environmental releases of these chemicals have also increased. Emerging information on adverse environmental and human health impacts of QACs is motivating a reconsideration of the risks and benefits across the life cycle of their production, use, and disposal. This work presents a critical review of the literature and scientific perspective developed by a multidisciplinary, multi-institutional team of authors from academia, governmental, and nonprofit organizations. The review evaluates currently available information on the ecological and human health profile of QACs and identifies multiple areas of potential concern. Adverse ecological effects include acute and chronic toxicity to susceptible aquatic organisms, with concentrations of some QACs approaching levels of concern. Suspected or known adverse health outcomes include dermal and respiratory effects, developmental and reproductive toxicity, disruption of metabolic function such as lipid homeostasis, and impairment of mitochondrial function. QACs' role in antimicrobial resistance has also been demonstrated. In the US regulatory system, how a QAC is managed depends on how it is used, for example in pesticides or personal care products. This can result in the same QACs receiving different degrees of scrutiny depending on the use and the agency regulating it. Further, the US Environmental Protection Agency's current method of grouping QACs based on structure, first proposed in 1988, is insufficient to address the wide range of QAC chemistries, potential toxicities, and exposure scenarios. Consequently, exposures to common mixtures of QACs and from multiple sources remain largely unassessed. Some restrictions on the use of QACs have been implemented in the US and elsewhere, primarily focused on personal care products. Assessing the risks posed by QACs is hampered by their vast structural diversity and a lack of quantitative data on exposure and toxicity for the majority of these compounds. This review identifies important data gaps and provides research and policy recommendations for preserving the utility of QAC chemistries while also seeking to limit adverse environmental and human health effects.


Assuntos
COVID-19 , Desinfetantes , Humanos , Compostos de Amônio Quaternário/química , Pandemias , Antibacterianos
4.
Cancer Causes Control ; 33(8): 1047-1057, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35419718

RESUMO

PURPOSE: The objective of this study is to document the prevalence of traditional, complementary, and alternative medicine (TCAM) use by adult cancer patients at a national teaching hospital in Malawi. We aim to document the products/therapies used, the reason for use, as well as patient-reported satisfaction with TCAM practitioners and modalities. METHODS: We conducted investigator-administered interviews with adult cancer patients presenting to the Kamuzu Central Hospital (KCH) Cancer Clinic in Lilongwe, Malawi between January and July 2018. The KCH is a national teaching hospital in the capital of Lilongwe, which serves patients with cancer from the northern half of Malawi. Descriptive statistics were used to describe TCAM use and logistic regression was applied to identify predictors of TCAM. RESULTS: A total of 263 participants completed the survey, of which 70% (n = 183) were female and average age was 45 (SD 14) years old. The prevalence of overall TCAM use was 84% (n = 222), and 60% (n = 157) of participants reported combining TCAM with conventional cancer treatment. The majority of patients used TCAM to directly treat their cancer versus for symptom management. Patients reported using faith-based healing (64%, n = 168), herbal medicine (56%, n = 148), diet change (46%, n = 120), and vitamins/minerals (23%, n = 61). Participants reported the highest satisfaction for physicians among practitioners and diet change for modalities. Female gender was found to be a predictor of TCAM with conventional treatment use, no other significant predictors were observed. CONCLUSION: There is a high prevalence of TCAM use among an adult population with cancer in Malawi, and a wide variety in the TCAM modalities used among patients. Additional studies are needed to identify risks and benefits of TCAM use to assist with policy and public health, patient safety, and holistically address the global burden of cancer.


Assuntos
Terapias Complementares , Neoplasias , Adolescente , Adulto , Feminino , Humanos , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Prevalência , Inquéritos e Questionários
5.
J Org Chem ; 86(1): 153-168, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33269585

RESUMO

The rate-determining step in free radical lipid peroxidation is the propagation of the peroxyl radical, where generally two types of reactions occur: (a) hydrogen-atom transfer (HAT) from a donor to the peroxyl radical; (b) peroxyl radical addition (PRA) to a "C═C" double bond. Peroxyl radical clocks have been used to determine the rate constants of HAT reactions (kH), but no radical clock is available to measure the rate constants of PRA reactions (kadd). In this work, we modified the analytical approach on the linoleate-based peroxyl radical clock to enable the simultaneous measurement of both kH and kadd. Compared to the original approach, this new approach involves the use of a strong reducing agent, LiAlH4, to completely reduce both HAT and PRA-derived products and the relative quantitation of total linoleate oxidation products with or without reduction. The new approach was then applied to measuring the kH and kadd values for several series of organic substrates, including para- and meta-substituted styrenes, substituted conjugated dienes, and cyclic alkenes. Furthermore, the kH and kadd values for a variety of biologically important lipids were determined for the first time, including conjugated fatty acids, sterols, coenzyme Q10, and lipophilic vitamins, such as vitamins D3 and A.

6.
Pediatr Blood Cancer ; 68(10): e29257, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34339099

RESUMO

BACKGROUND: Patient-reportedoutcomes (PROs) that assess health-related quality of life (HRQoL) are increasingly important components of cancer care and research that are infrequently used in sub-Saharan Africa (SSA). METHODS: We administered the Chichewa Pediatric Patient-Reported Outcome Measurement Information System Pediatric (PROMIS)-25 at diagnosis, active treatment, and follow-up among pediatric lymphoma patients in Lilongwe, Malawi. Mean scores were calculated for the six PROMIS-25 HRQoL domains (Mobility, Anxiety, Depressive Symptoms, Fatigue, Peer Relationships, Pain Interference). Differences in HRQoL throughout treatment were compared using the minimally important difference (MID) and an ANOVA analysis. Kaplan-Meier survival estimates and Cox hazard ratios for mortality are reported. RESULTS: Seventy-five children completed PROMIS-25 surveys at diagnosis, 35 (47%) during active treatment, and 24 (32%) at follow-up. The majority of patients died (n = 37, 49%) or were lost to follow-up (n = 6, 8%). Most (n = 51, 68%) were male, median age was 10 (interquartile range [IQR] 8-12), 48/73 (66%) presented with advanced stage III/IV, 61 (81%) were diagnosed with Burkitt lymphoma and 14 (19%) Hodgkin lymphoma. At diagnosis, HRQoL was poor across all domains, except for Peer Relationships. Improvements in HRQoL during active treatment and follow-up exceeded the MID. On exploratory analysis, fair-poor PROMIS Mobility <40 and severe Pain Intensity = 10 at diagnosis were associated with increased mortality risk and worse survival, but were not statistically significant. CONCLUSIONS: Pediatric lymphoma patients in Malawi present with poor HRQoL that improves throughout treatment and survivorship. Baseline PROMIS scores may provide important prognostic information. PROs offer an opportunity to include patient voices and prioritize holistic patient-centered care in low-resource settings.


Assuntos
Linfoma , Qualidade de Vida , Criança , Feminino , Seguimentos , Humanos , Linfoma/diagnóstico , Linfoma/epidemiologia , Linfoma/terapia , Malaui/epidemiologia , Masculino , Medidas de Resultados Relatados pelo Paciente
7.
Harm Reduct J ; 18(1): 18, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33573661

RESUMO

BACKGROUND: Peer workers or "peers" (workers with past or present drug use experience) are at the forefront of overdose response initiatives, and their role is essential in creating safe spaces for people who use drugs (PWUD). Working in overdose response settings has benefits for peer workers but is also stressful, with lasting emotional and mental health effects. Yet, little is known about the stressors peer workers face and what interventions can be implemented to support them in their roles. METHODS: This project used a community-based sequential mixed-methods research design. Eight peer researcher-led focus groups (n = 31) were conducted between November 2018 and March 2019 to assess needs of peer workers. The transcripts were thematically coded and analysed using interpretative description. These results informed a survey, which was conducted (n = 50) in September 2019 to acquire quantitative data on peer workers' perception of health, quality of life, working conditions and stressors. Frequency distributions were used to describe characteristics of participants. X2 distribution values with Yates correction were conducted to check for association between variables. RESULTS: Five themes emerged from the focus groups that point to stressors felt by peer workers: (1) financial insecurity; (2) lack of respect and recognition at work; (3) housing challenges; (4) inability to access and/or refer individuals to resources; and (5) constant exposure to death and trauma. Consistent with this, the factors that survey participants picked as one of their "top three stressors" included financial situation, work situation, and housing challenges. CONCLUSION: Peer workers are faced with a diversity of stressors in their lives which often reflect societal stigmatization of drug use. Recognition of these systemic stressors is critical in designing interventions to ease the emotional, physical and financial burden faced by peer workers.


Assuntos
Overdose de Drogas , Corrida , Transtornos Relacionados ao Uso de Substâncias , Overdose de Drogas/tratamento farmacológico , Humanos , Grupo Associado , Qualidade de Vida
8.
Paediatr Child Health ; 26(7): 402-407, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34777657

RESUMO

Concussion in children and adolescents is an important health concern. Most paediatric patients fully recover in 1 month or less following an acute concussion. However, some experience prolonged or persistent concussion symptoms for months. Those with prolonged post-concussion-related symptoms may have impaired quality of life, and limited involvement in social, academic, and physical activities with associated mental health implications. In this review, we share key updated clinical recommendations from the Living Guideline for Diagnosing and Managing Pediatric Concussion that will improve the way general paediatricians and family doctors diagnose and manage paediatric patients with suspected concussion.

9.
Cancer Causes Control ; 31(4): 393-402, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32124187

RESUMO

BACKGROUND: Breast cancer incidence in sub-Saharan Africa (SSA) is increasing, and SSA has the highest age-standardized breast cancer mortality rate worldwide. However, high-quality breast cancer data are limited in SSA. MATERIALS AND METHODS: We examined breast cancer patient and tumor characteristics among women in Lilongwe, Malawi and evaluated risk factor associations with patient outcomes. We consecutively enrolled 100 women ≥ 18 years with newly diagnosed, pathologically confirmed breast cancer into a prospective longitudinal cohort with systematically assessed demographic data, HIV status, and clinical characteristics. Tumor subtypes were further determined by immunohistochemistry, overall survival (OS) was estimated using Kaplan-Meier methods, and hazards ratios (HR) were calculated by Cox proportional hazard analyses. RESULTS: Of the 100 participants, median age was 49 years, 19 were HIV-positive, and 75 presented with late stage (III/IV) disease. HER2-enriched and triple-negative/basal-like subtypes represented 17% and 25% tumors, respectively. One-year OS for the cohort was 74% (95% CI 62-83%). Multivariable analyses revealed mortality was associated with HIV (HR, 5.15; 95% CI 1.58-16.76; p = 0.006), stage IV disease (HR, 8.86; 95% CI 1.07-73.25; p = 0.043), and HER2-enriched (HR, 7.46; 95% CI 1.21-46.07; p = 0.031), and triple-negative subtypes (HR, 7.80; 95% CI 1.39-43.69; p = 0.020). CONCLUSION: Late stage presentation, HER2-enriched and triple-negative subtypes, and HIV coinfection were overrepresented in our cohort relative to resource-rich settings and were associated with mortality. These findings highlight robust opportunities for population- and patient-level interventions across the entire cascade of care to improve breast cancer outcomes in low-income countries in SSA.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Infecções por HIV/epidemiologia , Humanos , Imuno-Histoquímica , Incidência , Estudos Longitudinais , Malaui/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Adulto Jovem
10.
Anal Chem ; 91(22): 14498-14507, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31613088

RESUMO

Conventional strategies for drug metabolite identification employ a combination of liquid chromatography-mass spectrometry (LC-MS), which offers higher throughput but provides limited structural information, and nuclear magnetic resonance spectroscopy, which can achieves the most definitive identification but lacks throughput. Ion mobility-mass spectrometry (IM-MS) is a rapid, two-dimensional analysis that separates ions on the basis of their gas-phase size and shape (reflected by collision cross section, CCS) and their mass-to-charge (m/z) ratios. The rapid nature of IM separation combined with the structural information provided by CCS make IM-MS a promising technique for obtaining more structural information on drug metabolites without sacrificing analytical throughput. Here, we present an in vitro biosynthesis coupled with IM-MS strategy for rapid generation and analysis of drug metabolites. Drug metabolites were generated in vitro using pooled subcellular fractions derived from human liver and analyzed using a rapid flow injection-IM-MS method. We measured CCS values for 19 parent drugs and their 37 metabolites generated in vitro (78 values in total), representing a wide variety of metabolic modifications. Post-IM fragmentation and computational modeling were used to support metabolite identifications and explore the structural characteristics driving behaviors observed in IM separation. Overall, we found the effects of metabolic modifications on the gas-phase structures of the metabolites to be highly dependent upon the structural characteristics of the parent compounds and the specific position of the modification. This in vitro biosynthesis coupled with rapid IM-MS analysis workflow represents a promising platform for rapid and high-confidence identification of drug metabolites, applicable at a large scale.


Assuntos
Preparações Farmacêuticas/análise , Preparações Farmacêuticas/metabolismo , Humanos , Fígado/metabolismo , Espectrometria de Massas/métodos
11.
Chem Res Toxicol ; 32(12): 2466-2478, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31730751

RESUMO

Benzalkonium chlorides (BACs) are widely used as disinfectants in cleaning products, medical products, and the food processing industry. Despite a wide range of reported toxicities, limited studies have been conducted on the metabolism of these compounds in animal models and none in human-derived cells or tissues. In this work, we report on the metabolism of BACs in human liver microsomes (HLM) and by recombinant human hepatic cytochrome P450 (CYP) enzymes. BAC metabolism in HLM was NADPH-dependent and displayed apparent half-lives that increased with BAC alkyl chain length (C10 < C12 < C14 < C16), suggesting enhanced metabolic stability of the more lipophilic, longer chain BACs. Metabolites of d7-benzyl labeled BAC substrates retained all deuteriums and there was no evidence of N-dealkylation. Tandem mass spectrometry fragmentation of BAC metabolites confirmed that oxidation occurs on the alkyl chain region. Major metabolites of C10-BAC were identified as ω-hydroxy-, (ω-1)-hydroxy-, (ω, ω-1)-diol-, (ω-1)-ketone-, and ω-carboxylic acid-C10-BAC by liquid chromatography-mass spectrometry comparison with synthetic standards. In a screen of hepatic CYP isoforms, recombinant CYP2D6, CYP4F2, and CYP4F12 consumed substantial quantities of BAC substrates and produced the major microsomal metabolites. The use of potent pan-CYP4 inhibitor HET0016, the specific CYP2D6 inhibitor quinidine, or both confirmed major contributions of CYP4- and CYP2D6-mediated metabolism in the microsomal disappearance of BACs. Kinetic characterization of C10-BAC metabolite formation in HLM demonstrated robust Michaelis-Menten kinetic parameters for ω-hydroxylation (Vmax = 380 pmol/min/mg, Km = 0.69 µM) and (ω-1)-hydroxylation (Vmax = 126 pmol/min/mg, Km = 0.13 µM) reactions. This work illustrates important roles for CYP4-mediated ω-hydroxylation and CYP2D6/CYP4-mediated (ω-1)-hydroxylation during the hepatic elimination of BACs, an environmental contaminant of emerging concern. Furthermore, we demonstrate that CYP-mediated oxidation of C10-BAC mitigates the potent inhibition of cholesterol biosynthesis exhibited by this short-chain BAC.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Compostos de Benzalcônio/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Desinfetantes/metabolismo , Amidinas/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases/química , Compostos de Benzalcônio/química , Isótopos de Carbono/química , Citocromo P-450 CYP2D6/química , Inibidores do Citocromo P-450 CYP2D6/farmacologia , Citocromo P-450 CYP3A/química , Inibidores do Citocromo P-450 CYP3A/farmacologia , Feminino , Humanos , Hidroxilação/efeitos dos fármacos , Cinética , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Oxirredução , Quinidina/farmacologia
13.
bioRxiv ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38798482

RESUMO

Benzalkonium chlorides (BACs) are commonly used disinfectants in a variety of consumer and food-processing settings, and the COVID-19 pandemic has led to increased usage of BACs. The prevalence of BACs raises the concern that BAC exposure could disrupt the gastrointestinal microbiota, thus interfering with the beneficial functions of the microbes. We hypothesize that BAC exposure can alter the gut microbiome diversity and composition, which will disrupt bile acid homeostasis along the gut-liver axis. In this study, male and female mice were exposed orally to d 7 -C12- and d 7 -C16-BACs at 120 µg/g/day for one week. UPLC-MS/MS analysis of liver, blood, and fecal samples of BAC-treated mice demonstrated the absorption and metabolism of BACs. Both parent BACs and their metabolites were detected in all exposed samples. Additionally, 16S rRNA sequencing was carried out on the bacterial DNA isolated from the cecum intestinal content. For female mice, and to a lesser extent in males, we found that treatment with either d 7 -C12- or d 7 -C16-BAC led to decreased alpha diversity and differential composition of gut bacteria with notably decreased actinobacteria phylum. Lastly, through a targeted bile acid quantitation analysis, we observed decreases in secondary bile acids in BAC-treated mice, which was more pronounced in the female mice. This finding is supported by decreases in bacteria known to metabolize primary bile acids into secondary bile acids, such as the families of Ruminococcaceae and Lachnospiraceae. Together, these data signify the potential impact of BACs on human health through disturbance of the gut microbiome and gut-liver interactions.

14.
Drug Metab Dispos ; 41(12): 2114-23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24046330

RESUMO

Noscapine is an antitussive and potential anticancer drug. Clinically significant interactions between warfarin and noscapine have been previously reported. In this study, to provide a basis for warfarin dosage adjustment, the inhibition kinetics of noscapine against warfarin metabolism was characterized. Our enzyme kinetics data obtained from human liver microsomes and recombinant CYP2C9 proteins indicate that noscapine is a competitive inhibitor of the (S)-warfarin 7-hydroxylation reaction by CYP2C9. Interestingly, noscapine also inhibited (S)-warfarin metabolism in a NADPH- and time-dependent manner, and removal of unbound noscapine and its metabolites by ultrafiltration did not reverse inhibition of (S)-warfarin metabolism by noscapine, suggesting mechanism-based inhibition of CYP2C9 by noscapine. Spectral scanning of the reaction between CYP2C9 and noscapine revealed the formation of an absorption spectrum at 458 nm, indicating the formation of a metabolite-intermediate complex. Surprisingly, noscapine is a 2- to 3-fold more efficient inactivator of CYP2C9.2 and CYP2C9.3 variants than it is of the wild type, by unknown mechanisms. Based on the inhibitory kinetic data, (S)-warfarin exposure is predicted to increase up to 7-fold (depending on CYP2C9 genotypes) upon noscapine coadministration, mainly due to mechanism-based inactivation of CYP2C9 by noscapine. Together, these results indicate that mechanism-based inhibition of CYP2C9 by noscapine may dramatically alter pharmacokinetics of warfarin and provide a basis for warfarin dosage adjustment when noscapine is coadministered.


Assuntos
Hidroxilação/fisiologia , Noscapina/farmacologia , Varfarina/metabolismo , Varfarina/farmacocinética , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP2C9 , Interações Medicamentosas/fisiologia , Humanos , Cinética , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Proteínas Recombinantes/metabolismo
15.
J Am Soc Mass Spectrom ; 33(6): 1061-1072, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35548857

RESUMO

Drug metabolite identification is a bottleneck of drug metabolism studies due to the need for time-consuming chromatographic separation and structural confirmation. Ion mobility-mass spectrometry (IM-MS), on the other hand, separates analytes on a rapid (millisecond) time scale and enables the measurement of collision cross section (CCS), a unique physical property related to an ion's gas-phase size and shape, which can be used as an additional parameter for identification of unknowns. A current limitation to the application of IM-MS to the identification of drug metabolites is the lack of reference CCS values. In this work, we assembled a large-scale database of drug and drug metabolite CCS values using high-throughput in vitro drug metabolite generation and a rapid IM-MS analysis with automated data processing. Subsequently, we used this database to train a machine learning-based CCS prediction model, employing a combination of conventional 2D molecular descriptors and novel 3D descriptors, achieving high prediction accuracies (0.8-2.2% median relative error on test set data). The inclusion of 3D information in the prediction model enables the prediction of different CCS values for different protomers, conformers, and positional isomers, which is not possible using conventional 2D descriptors. The prediction models, dmCCS, are available at https://CCSbase.net/dmccs_predictions.


Assuntos
Espectrometria de Mobilidade Iônica , Aprendizado de Máquina , Bases de Dados Factuais , Espectrometria de Mobilidade Iônica/métodos , Íons , Espectrometria de Massas/métodos
16.
JCO Glob Oncol ; 8: e2100388, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35772043

RESUMO

PURPOSE: There are limited data on treatment and outcomes for acute lymphoblastic leukemia (ALL) among adolescents and young adults in sub-Saharan Africa. We describe a prospective observational cohort in Malawi. METHODS: Patients age 15-39 years with newly diagnosed ALL at Kamuzu Central Hospital, Malawi, were enrolled from 2013 to 2019; follow-up was censored on December 2020. ALL diagnosis was confirmed on-site using immunohistochemistry and telepathology consultation involving pathologists in Malawi and the United States. All but four patients were treated with a modified pediatric-inspired regimen (Cancer and Leukemia Group B 10403 protocol). Key modifications included omission of asparaginase and no dose escalation for methotrexate. RESULTS: Of 19 participants, the median age was 22 (range 15-36) years. Of the 15 patients who initiated treatment, 11 (73%) achieved remission after induction, one (7%) died during induction, two (13%) had refractory disease, and one (7%) absconded. No patients were lost to follow-up. Eventually, 10 of 11 patients (91%) with confirmed remission relapsed. The median duration of first remission was 10 (range 3-22) months. Twelve of 15 treated patients (80%) had died at the time of censoring. Among treated patients, the 12- and 24-month overall survival was 50% (95% CI, 23 to 72) and 17% (95% CI, 3 to 42), respectively. CNS involvement was associated with worse survival. CONCLUSION: It is possible to treat adolescents and young adults with ALL in low-resource settings using a low-cost, pediatric-inspired regimen; however, outcomes are poor. Both cost and limitations in supportive care infrastructure limit intensive cytotoxic approaches such as asparaginase. Patient-reported outcomes are needed to understand the quality of life and cost-effectiveness. Critically, innovative, leap-frog therapies, such as monoclonal or bispecific antibodies, and feasible economic models for resource-limited settings are urgently needed.


Assuntos
Asparaginase , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Malaui/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Qualidade de Vida , Adulto Jovem
17.
JCO Glob Oncol ; 8: e2100315, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35175832

RESUMO

PURPOSE: Low health literacy is a leading cause of treatment abandonment among patients receiving cancer care at Kamuzu Central Hospital (KCH) in Malawi. METHODS: We developed cancer educational videos featuring Malawian providers and played them in the KCH oncology clinic. The videos addressed cancer-related topics, including disease biology, common myths, diagnostic procedures, treatment, side effects, and survivorship. After 6 months of implementation, we compared results from 50 pre- and postintervention surveys to assess change in cancer knowledge and care experience. RESULTS: Both pre- and postintervention cancer knowledge were good: a median of nine questions were answered correctly of 11 in both assessments. Despite the intervention, most continued to incorrectly identify cancer as an infection (pre: n = 26, 52%; post: n = 25, 50%; P = 1.0), although improvements were observed in patients' knowledge of correct actions for fever at home (pre: n = 38, 76%; post: n = 43, 86%; P = .31). Care experiences were overall good. Postintervention results indicate that more patients felt always listened to by their providers (pre: n = 18, 36%; post: n = 29, 58%; P < .01). However, we also noted a higher rate of patient dissatisfaction of care as more patients felt that they could not understand chemotherapy counseling (pre: n = 11, 22%; post: n = 22, 44%; P < .01). Assessments of video satisfaction indicate that patients found the videos very helpful in terms of understanding their disease (n = 47, 96%) and side effects (n = 48, 98%) and felt empowered to speak up with their providers (n = 46, 96%). CONCLUSION: Standardized education materials for patients that can be feasibly implemented throughout sub-Saharan Africa are urgently needed. Cancer educational videos are a low-cost way to educate and empower patients with cancer in resource-constrained settings although in-person discussions remain a crucial part of care.


Assuntos
Neoplasias , Participação do Paciente , Escolaridade , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Neoplasias/terapia , Inquéritos e Questionários
18.
Physiol Behav ; 228: 113201, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039382

RESUMO

BACKGROUND: The aim of the study was to investigate whether early changes (1-week) in energy balance-related measures would predict changes in body weight (BW) and fat losses in women living with overweight/obesity. METHODS: BW, body composition (DXA), resting energy expenditure (REE)(indirect calorimetry), olfactory performance (Sniffin' Sticks), appetite and palatability (visual analogue scale) were measured at baseline, after a 1-week of caloric restriction as well as post-intervention (at 10 and 20 weeks) in a group of 30 women living with overweight/obesity. RESULTS: A significant decrease in REE (p = 0.033) was noted after 1 week. Fasting desire to eat (p = 0.004), hunger (p = 0.001) and prospective food consumption (p = 0.001) all increased after 1 week. Similarly, significant increases in AUC SQ for desire to eat (p = 0.01), hunger (p = 0.005) and prospective food consumption (p = 0.001) were noted after 1 week. However, these early changes were not associated to final BW or FM losses at the end of the weight loss intervention. CONCLUSION: Despite significant changes in REE and appetite soon after the onset of a BW loss intervention, these early changes do not seem to predict final BW or FM losses at the end of the program in women living with overweight/obesity.


Assuntos
Apetite , Sobrepeso , Composição Corporal , Peso Corporal , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Menopausa , Obesidade , Estudos Prospectivos
19.
Toxicol Rep ; 8: 646-656, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868951

RESUMO

Humans are frequently exposed to Quaternary Ammonium Compounds (QACs). QACs are ubiquitously used in medical settings, restaurants, and homes as cleaners and disinfectants. Despite their prevalence, nothing is known about the health effects associated with chronic low-level exposure. Chronic QAC toxicity, only recently identified in mice, resulted in developmental, reproductive, and immune dysfunction. Cell based studies indicate increased inflammation, decreased mitochondrial function, and disruption of cholesterol synthesis. If these findings translate to human toxicity, multiple physiological processes could be affected. This study tested whether QAC concentrations could be detected in the blood of 43 human volunteers, and whether QAC concentrations influenced markers of inflammation, mitochondrial function, and cholesterol synthesis. QAC concentrations were detected in 80 % of study participants. Blood QACs were associated with increase in inflammatory cytokines, decreased mitochondrial function, and disruption of cholesterol homeostasis in a dose dependent manner. This is the first study to measure QACs in human blood, and also the first to demonstrate statistically significant relationships between blood QAC and meaningful health related biomarkers. Additionally, the results are timely in light of the increased QAC disinfectant exposure occurring due to the SARS-CoV-2 pandemic. MAIN FINDINGS: This study found that 80 % of study participants contained QACs in their blood; and that markers of inflammation, mitochondrial function, and sterol homeostasis varied with blood QAC concentration.

20.
Int J Drug Policy ; 88: 103015, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33176249

RESUMO

BACKGROUND: The province of British Columbia (BC), Canada is amid dual public health emergencies in which the overdose epidemic declared in 2016 has been exacerbated by restrictions imposed by the Coronavirus Disease of 2019 (COVID-19) pandemic. Experiential workers, commonly known as 'peers' (workers with past or present drug use experience) are at the forefront of overdose response initiatives and are essential in creating safe spaces for people who use drugs (PWUD) in harm reduction. Working in overdose response environments can be stressful, with lasting emotional and mental health effects. There is limited knowledge about the personal meaning that experiential workers derive from their work, which serve as motivators for them to take on these often-stressful roles. METHODS: This project used a community-based qualitative research design. The research was based at two organizations in BC. Eight experiential worker-led focus groups were conducted (n = 31) where participants spoke about their roles, positive aspects of their jobs, challenges they face, and support needs in harm reduction work. Transcripts were coded and analyzed using interpretative description to uncover the meaning derived from experiential work. RESULTS: Three themes emerged from focus group data that describe the meanings which serve as motivators for experiential workers to continue working in overdose response environments: (1) A sense of purpose from helping others; (2) Being an inspiration for others, and; (3) A sense of belonging. CONCLUSION: Despite the frequent hardships and loss that accompany overdose response work, experiential workers identified important aspects that give their work meaning. These aspects of their work may help to protect workers from the emotional harms associated with stressful work as well as the stigma of substance use. Recognizing the importance of experiential work and its role in the lives of PWUD can help inform and strengthen organizational supports.


Assuntos
COVID-19 , Overdose de Drogas/prevenção & controle , Usuários de Drogas/psicologia , Emoções , Motivação , Influência dos Pares , Serviços Preventivos de Saúde , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Idoso , Colúmbia Britânica , Escolha da Profissão , Overdose de Drogas/psicologia , Feminino , Grupos Focais , Redução do Dano , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto Jovem
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