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1.
Arch Toxicol ; 95(11): 3475-3495, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34510227

RESUMEN

microRNAs (miRNAs or miRs) are short non-coding RNA molecules which have been shown to be dysregulated and released into the extracellular milieu as a result of many drug and non-drug-induced pathologies in different organ systems. Consequently, circulating miRs have been proposed as useful biomarkers of many disease states, including drug-induced tissue injury. miRs have shown potential to support or even replace the existing traditional biomarkers of drug-induced toxicity in terms of sensitivity and specificity, and there is some evidence for their improved diagnostic and prognostic value. However, several pre-analytical and analytical challenges, mainly associated with assay standardization, require solutions before circulating miRs can be successfully translated into the clinic. This review will consider the value and potential for the use of circulating miRs in drug-safety assessment and describe a systems approach to the analysis of the miRNAome in the discovery setting, as well as highlighting standardization issues that at this stage prevent their clinical use as biomarkers. Highlighting these challenges will hopefully drive future research into finding appropriate solutions, and eventually circulating miRs may be translated to the clinic where their undoubted biomarker potential can be used to benefit patients in rapid, easy to use, point-of-care test systems.


Asunto(s)
Biomarcadores Farmacológicos , MicroARNs/sangre , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/diagnóstico , Humanos , MicroARNs/análisis , Sensibilidad y Especificidad
2.
Allergy ; 75(3): 636-647, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31549414

RESUMEN

BACKGROUND: Abacavir is associated with hypersensitivity reactions in individuals positive for the HLA-B*57:01 allele. The drug binds within the peptide binding groove of HLA-B*57:01 altering peptides displayed on the cell surface. Presentation of these HLA-abacavir-peptide complexes to T-cells is hypothesized to trigger a CD8+ T-cell response underpinning the hypersensitivity. Thus, the aim of this study was to explore the relationship between the structure of abacavir with HLA-B*57:01 binding and the CD8+ T-cell activation. METHODS: Seventeen abacavir analogues were synthesized and cytokine secretion from abacavir/abacavir analogue-responsive CD8+ T-cell clones was measured using IFN-γ ELIspot. In silico docking studies were undertaken to assess the predicted binding poses of the abacavir analogues within the HLA-B*57:01 peptide binding groove. In parallel, the effect of selected abacavir analogues on the repertoire of self-peptides presented by cellular HLA-B*57:01 was characterized using mass spectrometry. RESULTS: Abacavir and ten analogues stimulated CD8+ T-cell IFN-γ release. Molecular docking of analogues that retained antiviral activity demonstrated a relationship between predicted HLA-B*57:01 binding orientations and the ability to induce a T-cell response. Analogues that stimulated T-cells displayed a perturbation of the natural peptides displayed by HLA-B*57:01. The antigen-specific CD8+ T-cell response was dependent on the enantiomeric form of abacavir at both cyclopropyl and cyclopentyl regions. CONCLUSION: Alteration of the chemical constitution of abacavir generates analogues that retain a degree of pharmacological activity, but have variable ability to activate T-cells. Modelling and immunopeptidome analysis delineate how drug HLA-B*57:01 binding and peptide display by antigen presenting cells relate to the activation of CD8+ T-cells.


Asunto(s)
Linfocitos T CD8-positivos , Hipersensibilidad a las Drogas , Didesoxinucleósidos , Antígenos HLA-B/genética , Humanos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad
3.
J Surg Res ; 247: 202-210, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31753555

RESUMEN

BACKGROUND: Implants used in abdominal wall reconstruction are associated with intra-abdominal inflammation that can cause complications such as adhesions, fistulae, or failure of the implant. This study analyzed the inflammatory response of human peritoneum explants when exposed to different implant materials including synthetic and biological (cross-linked and non-cross-linked). MATERIALS AND METHODS: Human peritoneum explants (parietal and visceral) were incubated in culture with implants used for abdominal wall reconstruction. Implants included Permacol (biological implant with chemical cross-linking); Biodesign and Strattice (biological implants without chemical cross-linking); Prolene (synthetic nonabsorbable); and Vicryl (synthetic absorbable). Control peritoneum samples were incubated without implant. Cytokine concentrations and corresponding gene expression were measured by enzyme-linked immunosorbent assay and quantitative polymerase chain reaction, respectively. Further evaluation included assessment of tissue viability and implant-cytokine adsorption. RESULTS: Incubation of human peritoneal explants with Biodesign or Strattice was associated with a significant reduction in interleukin-6, interleukin-1ß, and tumour necrosis factor alpha protein and gene expression compared with control. These could not be explained by reduced cell viability or implant-cytokine adsorption. Incubation of explants in Biodesign-conditioned media displayed a similar effect to incubation of explants with Biodesign itself. CONCLUSIONS: Human peritoneal explants cultured with different mesh implant materials show an altered inflammatory cytokine response suggesting a tissue-specific response. Downregulation of key inflammatory cytokines by the peritoneum exposed to non-cross-linked biological implants may be mediated by the release of soluble factors from these implants inhibiting cytokine gene expression. This ex vivo human peritoneal system provides a novel preclinical model to investigate peritoneum-implant interactions.


Asunto(s)
Peritoneo/inmunología , Peritonitis/prevención & control , Procedimientos de Cirugía Plástica/efectos adversos , Prótesis e Implantes/efectos adversos , Mallas Quirúrgicas/efectos adversos , Pared Abdominal/cirugía , Citocinas/inmunología , Citocinas/metabolismo , Perfilación de la Expresión Génica , Humanos , Hernia Incisional/cirugía , Ensayo de Materiales , Peritoneo/patología , Peritonitis/inmunología , Peritonitis/patología , Procedimientos de Cirugía Plástica/instrumentación , Adherencias Tisulares/inmunología , Adherencias Tisulares/patología , Adherencias Tisulares/prevención & control , Técnicas de Cultivo de Tejidos
4.
Arch Toxicol ; 94(4): 1251-1263, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32112222

RESUMEN

In addition to hepatocytes, the liver comprises a host of specialised non-parenchymal cells which are important to consider in the development of in vitro models which are both physiologically and toxicologically relevant. We have characterized a 3D co-culture system comprising primary human hepatocytes (PHH) and non-parenchymal cells (NPC) and applied it to the investigation of acetaminophen-induced toxicity. Firstly, we titrated ratios of PHH:NPC and confirmed the presence of functional NPCs via both immunohistochemistry and activation with both LPS and TGF-ß. Based on these data we selected a ratio of 2:1 PHH:NPC for further studies. We observed that spheroids supplemented with NPCs were protected against acetaminophen (APAP) toxicity as determined by ATP (up to threefold difference in EC50 at day 14 compared to hepatocytes alone) and glutathione depletion, as well as miR-122 release. APAP metabolism was also altered in the presence of NPCs, with significantly lower levels of APAP-GSH detected. Expression of several CYP450 enzymes involved in the bioactivation of APAP was also lower in NPC-containing spheroids. Spheroids containing NPCs also expressed higher levels of miRNAs which have been implicated in APAP-induced hepatotoxicity, including miR-382 and miR-155 which have potential roles in liver regeneration and inflammation, respectively. These data indicate that the interaction between hepatocytes and NPCs can have significant metabolic and toxicological consequences important for the correct elucidation of hepatic safety mechanisms.


Asunto(s)
Acetaminofén/toxicidad , Analgésicos no Narcóticos/toxicidad , Hígado/efectos de los fármacos , Acetaminofén/efectos adversos , Analgésicos no Narcóticos/efectos adversos , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas , Técnicas de Cocultivo , Sistema Enzimático del Citocromo P-450 , Hepatocitos , Humanos , Inflamación , Masculino , MicroARNs , Conformación Molecular
5.
Proc Natl Acad Sci U S A ; 114(30): 8071-8076, 2017 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-28696308

RESUMEN

Small, noncoding RNAs are short untranslated RNA molecules, some of which have been associated with cancer development. Recently we showed that a class of small RNAs generated during the maturation process of tRNAs (tRNA-derived small RNAs, hereafter "tsRNAs") is dysregulated in cancer. Specifically, we uncovered tsRNA signatures in chronic lymphocytic leukemia and lung cancer and demonstrated that the ts-4521/3676 cluster (now called "ts-101" and "ts-53," respectively), ts-46, and ts-47 are down-regulated in these malignancies. Furthermore, we showed that tsRNAs are similar to Piwi-interacting RNAs (piRNAs) and demonstrated that ts-101 and ts-53 can associate with PiwiL2, a protein involved in the silencing of transposons. In this study, we extended our investigation on tsRNA signatures to samples collected from patients with colon, breast, or ovarian cancer and cell lines harboring specific oncogenic mutations and representing different stages of cancer progression. We detected tsRNA signatures in all patient samples and determined that tsRNA expression is altered upon oncogene activation and during cancer staging. In addition, we generated a knocked-out cell model for ts-101 and ts-46 in HEK-293 cells and found significant differences in gene-expression patterns, with activation of genes involved in cell survival and down-regulation of genes involved in apoptosis and chromatin structure. Finally, we overexpressed ts-46 and ts-47 in two lung cancer cell lines and performed a clonogenic assay to examine their role in cell proliferation. We observed a strong inhibition of colony formation in cells overexpressing these tsRNAs compared with untreated cells, confirming that tsRNAs affect cell growth and survival.


Asunto(s)
Neoplasias/metabolismo , ARN Pequeño no Traducido/metabolismo , Células A549 , Estudios de Casos y Controles , Células HEK293 , Humanos , Oncogenes
6.
Hepatology ; 64(5): 1743-1756, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27532775

RESUMEN

Hepatocytes are dynamic cells that, upon injury, can alternate between nondividing differentiated and dedifferentiated proliferating states in vivo. However, in two-dimensional cultures, primary human hepatocytes (PHHs) rapidly dedifferentiate, resulting in loss of hepatic functions that significantly limits their usefulness as an in vitro model of liver biology, liver diseases, as well as drug metabolism and toxicity. Thus, understanding the underlying mechanisms and stalling of the dedifferentiation process would be highly beneficial to establish more-accurate and relevant long-term in vitro hepatocyte models. Here, we present comprehensive analyses of whole proteome and transcriptome dynamics during the initiation of dedifferentiation during the first 24 hours of culture. We report that early major rearrangements of the noncoding transcriptome, hallmarked by increased expression of small nucleolar RNAs, long noncoding RNAs, microRNAs (miRNAs), and ribosomal genes, precede most changes in coding genes during dedifferentiation of PHHs, and we speculated that these modulations could drive the hepatic dedifferentiation process. To functionally test this hypothesis, we globally inhibited the miRNA machinery using two established chemically distinct compounds, acriflavine and poly-l-lysine. These inhibition experiments resulted in a significantly impaired miRNA response and, most important, in a pronounced reduction in the down-regulation of hepatic genes with importance for liver function. Thus, we provide strong evidence for the importance of noncoding RNAs, in particular, miRNAs, in hepatic dedifferentiation, which can aid the development of more-efficient differentiation protocols for stem-cell-derived hepatocytes and broaden our understanding of the dynamic properties of hepatocytes with respect to liver regeneration. CONCLUSION: miRNAs are important drivers of hepatic dedifferentiation, and our results provide valuable information regarding the mechanisms behind liver regeneration and possibilities to inhibit dedifferentiation in vitro. (Hepatology 2016;64:1743-1756).


Asunto(s)
Desdiferenciación Celular/genética , Hepatocitos/fisiología , MicroARNs/fisiología , Adulto , Anciano , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Transcriptoma
7.
Drug Metab Dispos ; 45(4): 419-429, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28137721

RESUMEN

Reliable and versatile hepatic in vitro systems for the prediction of drug pharmacokinetics and toxicity are essential constituents of preclinical safety assessment pipelines for new medicines. Here, we compared three emerging cell systems-hepatocytes derived from induced pluripotent stem cells, HepaRG cells, and three-dimensional primary human hepatocyte (PHH) spheroids-at transcriptional and functional levels in a multicenter study to evaluate their potential as predictive models for drug-induced hepatotoxicity. Transcriptomic analyses revealed widespread gene expression differences between the three cell models, with 8148 of 17,462 analyzed genes (47%) being differentially expressed. Expression levels of genes involved in the metabolism of endogenous as well as xenobiotic compounds were significantly elevated in PHH spheroids, whereas genes involved in cell division and endocytosis were significantly upregulated in HepaRG cells and hepatocytes derived from induced pluripotent stem cells, respectively. Consequently, PHH spheroids were more sensitive to a panel of drugs with distinctly different toxicity mechanisms, an effect that was amplified by long-term exposure using repeated treatments. Importantly, toxicogenomic analyses revealed that transcriptomic changes in PHH spheroids were in compliance with cholestatic, carcinogenic, or steatogenic in vivo toxicity mechanisms at clinically relevant drug concentrations. Combined, the data reveal important phenotypic differences between the three cell systems and suggest that PHH spheroids can be used for functional investigations of drug-induced liver injury in vivo in humans.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Hepatocitos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Modelos Biológicos , Esferoides Celulares/metabolismo , Xenobióticos/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/economía , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Perfilación de la Expresión Génica , Hepatocitos/efectos de los fármacos , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Concentración 50 Inhibidora , Esferoides Celulares/efectos de los fármacos , Xenobióticos/metabolismo
8.
J Biol Chem ; 290(46): 27473-86, 2015 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-26391395

RESUMEN

The key sensor of energy status in mammalian cells, AMP-activated protein kinase (AMPK), can also be activated by the AMP analog aminoimidazolecarboxamide nucleoside monophosphate (ZMP) generated directly from aminoimidazolecarboxamide ribonucleoside (AICAR) or from inhibition of purine synthesis by the antifolate pemetrexed (PTX), a drug used extensively in the treatment of lung cancers. Despite this common mechanism, signaling downstream of AMPK activated by PTX or AICAR differed. AICAR-activated AMPK inhibited mTORC1 both directly by phosphorylation of the mTORC1 subunit Raptor and indirectly by phosphorylation of the regulator TSC2. In contrast, PTX-activated AMPK inhibited mTORC1 solely through Raptor phosphorylation. This dichotomy was due to p53 function. Transcription of p53 target genes, including TSC2, was activated by AICAR but not by PTX. Although both PTX and AICAR stabilized p53, only AICAR activated Chk2 phosphorylation, stimulating p53-dependent transcription. However, Raptor phosphorylation by AMPK was independent of p53 and was sufficient, after PTX treatment, to inhibit mTORC1. We concluded that PTX effects on mTORC1 were independent of TSC2 and p53 and that the activation of a p53 transcriptional response by AICAR was due to an activation of Chk2 that was not elicited by PTX.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Antineoplásicos/farmacología , Antagonistas del Ácido Fólico/farmacología , Complejos Multiproteicos/metabolismo , Pemetrexed/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Quinasa de Punto de Control 2/genética , Activación Enzimática/efectos de los fármacos , Células HCT116 , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Fosforilación , Proteína Reguladora Asociada a mTOR , Ribonucleótidos/farmacología , Transducción de Señal/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética
9.
Chem Res Toxicol ; 29(12): 1936-1955, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27661221

RESUMEN

The liver is an organ with critical importance for drug treatment as the disposition and response to a given drug is often determined by its hepatic metabolism. Patient-specific factors can entail increased susceptibility to drug-induced liver injury, which constitutes a major risk for drug development programs causing attrition of promising drug candidates or costly withdrawals in postmarketing stages. Hitherto, mainly animal studies and 2D hepatocyte systems have been used for the examination of human drug metabolism and toxicity. Yet, these models are far from satisfactory due to extensive species differences and because hepatocytes in 2D cultures rapidly dedifferentiate resulting in the loss of their hepatic phenotype and functionality. With the increasing comprehension that 3D cell culture systems more accurately reflect in vivo physiology, in the recent decade more and more research has focused on the development and optimization of various 3D culture strategies in an attempt to preserve liver properties in vitro. In this contribution, we critically review these developments, which have resulted in an arsenal of different static and perfused 3D models. These systems include sandwich-cultured hepatocytes, spheroid culture platforms, and various microfluidic liver or multiorgan biochips. Importantly, in many of these models hepatocytes maintain their phenotype for prolonged times, which allows probing the potential of newly developed chemical entities to cause chronic hepatotoxicity. Moreover, some platforms permit the investigation of drug action in specific genetic backgrounds or diseased hepatocytes, thereby significantly expanding the repertoire of tools to detect drug-induced liver injuries. It is concluded that the development of 3D liver models has hitherto been fruitful and that systems are now at hand whose sensitivity and specificity in detecting hepatotoxicity are superior to those of classical 2D culture systems. For the future, we highlight the need to develop more integrated coculture model systems to emulate immunotoxicities that arise due to complex interactions between hepatocytes and immune cells.


Asunto(s)
Pruebas de Función Hepática , Animales , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Modelos Biológicos
10.
Chem Res Toxicol ; 27(2): 175-7, 2014 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-24476427

RESUMEN

HLA-A*31:01 is associated with carbamazepine (CBZ) hypersensitivity in Caucasian and Japanese populations. Herein, we show that HLA-A*31:01+ restricted the activation of carbamazepine-specific CD8(+) T-cells, which provides an immunological basis for the genetic association. Furthermore, CD4(+) T-cells were activated with carbamazepine in a HLA-DRB1*04:04-restricted manner, indicating that a common HLA haplotype may contribute to the multiclonal T-cell response seen in European patients with CBZ hypersensitivity.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Carbamazepina/efectos adversos , Hipersensibilidad a las Drogas/inmunología , Antígenos HLA-A/inmunología , Células Presentadoras de Antígenos/inmunología , Células Clonales/inmunología , Humanos
11.
Health Care Anal ; 22(3): 255-71, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23359104

RESUMEN

The study examined the question of who should make decisions for a National Health Scheme about the allocation of health resources when the health states of beneficiaries could change because of adaptation. Eight semi-structured small group discussions were conducted. Following focus group theory, interviews commenced with general questions followed by transition questions and ended with a 'focus' or 'key' question. Participants were presented with several scenarios in which patients adapted to their health states. They were then asked their views about the appropriate role of the public, patients and health professionals in making social judgements of quality of life. After discussion and debate, all groups were asked the key question: 'In light of adaptation, who should evaluate quality of life for the purpose of setting priorities in the allocation of health care?' In all groups participants presented strong arguments for and against decision making by patients, the public and health professionals. However, most groups thought a representative body which included a range of perspectives should make the relevant judgements. This is at odds with the recommendations in most national pharmaceutical guidelines. The main conclusion of the paper is that health economists and other researchers should explore the possibility of adopting a deliberative, consensus-based approach to evaluating health-related quality of life when such judgements are to be used to inform priority setting in a public system.


Asunto(s)
Adaptación Psicológica , Enfermedad Crónica , Personas con Discapacidad , Prioridades en Salud/organización & administración , Participación de la Comunidad , Toma de Decisiones , Atención a la Salud , Grupos Focales , Investigación sobre Servicios de Salud , Humanos , Entrevistas como Asunto , Investigación Cualitativa , Calidad de Vida , Asignación de Recursos/organización & administración
12.
Chem Res Toxicol ; 26(5): 759-66, 2013 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-23541086

RESUMEN

Susceptibility to abacavir hypersensitivity has been attributed to possession of the specific human leukocyte antigen allele HLA-B*57:01. HLA-B*57:01-restricted activation of CD8+ T-cells provides a link between the genetic association and the iatrogenic disease. The objectives of this study were to characterize the functionality of drug-responsive CD8+ T-cell clones generated from HLA-B*57:01+ drug-naive subjects and to explore the relationship between abacavir accumulation in antigen presenting cells and the T-cell response. Seventy-four CD8+ clones expressing different Vß receptors were shown to proliferate and kill target cells via different mechanisms when exposed to abacavir. Certain clones were activated with abacavir in the absence of antigen presenting cells. Analysis of the remaining clones revealed two pathways of drug-dependent T-cell activation. Overnight incubation of antigen presenting cells with abacavir, followed by repeated washing to remove soluble drug, activated approximately 50% of the clones, and the response was blocked by glutaraldehyde fixation. In contrast, a 1 h antigen presenting cell pulse did not activate any of the clones. Accumulation of abacavir in antigen presenting cells was rapid (less than 1 h), and the intracellular concentrations were maintained for 16 h. However, intracellular abacavir was not detectable by mass spectrometry after pulsing. These data suggest that T-cells can be activated by abacavir through a direct interaction with surface and intracellular major histocompatibility complex (MHC) molecules. With the former, abacavir seemingly participates in the MHC T-cell receptor binding interaction. In contrast, the latter pathway likely involves MHC binding peptides displayed as a consequence of abacavir exposure, but not abacavir itself.


Asunto(s)
Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/efectos de los fármacos , Didesoxinucleósidos/farmacología , Antígenos HLA-B/inmunología , Activación de Linfocitos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Muerte Celular/efectos de los fármacos , Línea Celular , Proliferación Celular , Células Clonales/citología , Células Clonales/efectos de los fármacos , Células Clonales/inmunología , Citocinas/inmunología , Didesoxinucleósidos/química , Relación Dosis-Respuesta a Droga , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Relación Estructura-Actividad
13.
Chem Res Toxicol ; 26(7): 1064-72, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23697900

RESUMEN

Human exposure to abacavir, a primary alcohol antiretroviral, is associated with the development of immunological drug reactions in individuals carrying the HLA risk allele B*57:01. Interaction of abacavir with antigen presenting cells results in cell activation through an Hsp70-mediated Toll-like receptor pathway and the provision of T-cell antigenic determinants. Abacavir's electrophilic aldehyde metabolites are potential precursors of neoantigens. Herein, we have used mass spectrometry to study the oxidative metabolism of abacavir in EBV-transformed human B-cells. RNA and protein were isolated from the cells and subjected to transcriptomic and mass spectrometric analyses to identify the redox enzymes expressed. Low levels of isomeric abacavir carboxylic acids were detected in subcellular fractions of EBV-transformed human B-cells incubated with abacavir. Metabolite formation was time-dependent but was not reduced by an inhibitor of Class I alcohol dehydrogenases. Relatively high levels of mRNA were detected for several redox enzymes, including alcohol dehydrogenase 5 (Class III), aldehyde dehydrogenases (ALDH3A2, ALDH6A1, and ALDH9A1), CYP1B1, CYP2R1, CYP7B1, and hydroxysteroid dehydrogenase 10. Over 2600 proteins were identified by mass spectrometry. More than 1000 of these proteins exhibited catalytic activity, and 80 were oxido-reductases. This is the first proteomic inventory of enzymes in antigen presenting cells. However, neither of the hepatic alcohol dehydrogenases of Class I which metabolize abacavir in vitro was expressed at the protein level. Nevertheless the metabolic production of abacavir carboxylic acids by B-cell fractions implies abacavir-treated immune cells might be exposed to the drug's protein-reactive aldehyde metabolites in vivo.


Asunto(s)
Células Presentadoras de Antígenos/citología , Células Presentadoras de Antígenos/metabolismo , Didesoxinucleósidos/metabolismo , Biotransformación , Línea Celular Transformada , Citosol/metabolismo , Didesoxinucleósidos/química , Humanos , Cinética , Hígado/citología , Espectrometría de Masas , Conformación Molecular , Oxidación-Reducción , Fracciones Subcelulares/química , Fracciones Subcelulares/metabolismo , Factores de Tiempo
14.
J Am Coll Health ; 71(7): 2115-2122, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34347578

RESUMEN

OBJECTIVE: The unique features of college experience make it essential to address escalating mental-health challenges beyond college campuses. In 2010, we launched college-student focused (CSF) care nested within an adult day treatment program in a psychiatric hospital. The CSF care consists of student group therapies, individual consultation services for hospital staff and student-patients, and student-focused mental health guides for patients and families. This study preliminarily examined the clinical impact of CSF care on post-treatment symptoms reduction. PARTICIPANTS AND METHODS: In 235 college student-patients admitted to the day program between 2011 July to 2013 January, we assessed the targeted outcomes of the CSF care, using a newly developed CSF questionnaire. RESULTS: Higher levels of CSF care-related outcomes predicted reduced post-treatment depression and anxiety, even after controlling for baseline clinical symptoms and post-treatment skills usage. CONCLUSIONS: These results highlighted the benefits and need for CSF care on a healthcare system level.

15.
Animals (Basel) ; 13(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37889630

RESUMEN

Projects that aim to improve the welfare of equids worldwide usually involve people from different countries and cultures working together. Given that professionals involved with multi-stakeholder projects often work cross-culturally, this study examined their experiences regarding the challenges involved in, and their reflections on, how to work in a culturally sensitive way. Semi-structured interviews were conducted with 14 participants working in a total of 29 countries and analysed using thematic analysis. Key response themes emerged from the responses to questions covering the areas of perceptions of animal welfare, challenges working cross-culturally and embracing cultural sensitivity. The overriding theme regarding perceptions of animal welfare was that of barriers to animal welfare, under which emerged the subthemes of limited financial and material resources, limited understanding of the tenets of animal welfare, and attachment to traditional medicines and practices. Exploring the key challenges resulted in two themes: challenges regarding the local context and etiquette, and those regarding working with different stakeholders. Considering cultural sensitivity, again, two themes emerged: the importance of trust and respect, and of working with local partners. Previous works have highlighted the importance of shared linguistic knowledge, interpersonal skills and cultural knowledge, and these elements also emerged in this research. As well as providing insights into the challenges of working cross-culturally, the findings of this study have enabled the development of suggestions for how this work could be taken forward in a practical way to be of use to professionals in this sector.

16.
Breastfeed Rev ; 20(3): 27-38, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23330448

RESUMEN

This qualitative study, conducted by volunteers from the Australian Capital Territory/Southern New South Wales (ACT/SNSW) Branch of the Australian Breastfeeding Association (ABA), explored the breastfeeding experiences of younger mothers (under the age of 26 years) in the ACT by conducting three focus groups. The study aimed to gain an understanding of how, when and where younger mothers want and need to receive breastfeeding information and support. Younger mothers provided important insights into their breastfeeding experiences, which were often characterised by judgement from health professionals and the wider public. A number of key issues were identified including: breastfeeding is far from a cultural norm in our society and as such the risks of artificial baby milk are not clearly understood by many younger mothers; younger mothers are strongly influenced by their partners, mothers and peers and they rely upon them for breastfeeding information and support. Younger mothers indicated that a number of improvements could be made to the way that breastfeeding information and support is currently provided within the ACT. The findings indicated that younger mothers (and their significant others) would benefit from receiving clear, concise and consistent breastfeeding information early on in their pregnancy, that is positive in tone, not necessarily 'young mum' specific and consistent with a 'less is more' approach. Younger mothers indicated that after the birth of their baby this breastfeeding information needs to be complemented by readily accessible, seamless, respectful support for as long as they need to establish breastfeeding and overcome any breastfeeding challenges. The focus group findings were largely consistent with the existing literature available on younger mothers and breastfeeding and provide valuable insights to all stakeholders responsible for providing breastfeeding information and support to younger mothers.


Asunto(s)
Lactancia Materna/métodos , Lactancia Materna/estadística & datos numéricos , Consejo/métodos , Educación en Salud/métodos , Relaciones Madre-Hijo , Madres/educación , Apoyo Social , Adulto , Factores de Edad , Anécdotas como Asunto , Australia , Toma de Decisiones , Femenino , Grupos Focales , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Madres/psicología , Adulto Joven
17.
Animals (Basel) ; 12(21)2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-36359029

RESUMEN

One of the key welfare concerns for horses in the United Kingdom is lack of recognition of fear in horses. This study aimed to gain an understanding of how well horse care givers recognise fear and/or anxiety in horses by interviewing equine behaviourists (who interact with large numbers of horse care givers and talk to them about this topic routinely). The experiences of Animal Behaviour and Training Council (ABTC)-registered equine behaviourists working with horse caregivers were examined, including the ability of clients to recognise fear and/or anxiety in horses, how clients respond when discussing fear as the reason for their horse's behaviour, and what explanations the participants use to explain fear and anxiety. Semi-structured interviews were conducted with nine participants and analysed using thematic analysis before being written up to reflect the discussion points. When asked how well horse caregivers recognise fear and/or anxiety in horses, three key response themes emerged: caregivers are extremely poor at recognizing fear and anxiety in horses; some clients do recognise behavioural signs indicating fear and/or anxiety but only the overt signs (e.g., rearing, running away) rather than the more subtle signs (e.g., tension in face, subtle avoidance behaviours such as a hesitant gait); and fear and/or anxiety behaviour is often misinterpreted or mislabelled. These key themes recurred throughout several other interview questions. This study has provided initial insights into the lack of recognition of fear and anxiety of horses by their caregivers in the United Kingdom as well as tried and tested approaches to conversations to change this. Such synthesis of experience and techniques across the equine behaviour sector, together with the information gained regarding perception of equine caregivers, could be a valuable approach to improve the effectiveness of behaviour consultations and welfare initiatives.

18.
Midwifery ; 111: 103388, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35640358

RESUMEN

BACKGROUND: The birth plan was introduced in the 1980s to facilitate communication between maternity care providers and women and increase agency for childbearing women in the face of medicalised birth. Forty years on, the birth plan is a heterogeneous document with uncertainty surrounding its purpose, process, and impact. The aim of this review was to synthesise the evidence and improve understanding of the purpose, process and impact of the birth plan on childbearing women's experiences and outcomes. METHODS: This systematic review followed the PRISMA guidelines. A comprehensive search strategy was designed and applied to electronic databases CINAHL, MEDLINE, PsychINFO, Cochrane Library, Scopus, and ClinicalTrials.gov. Articles were appraised using the Crowe Critical Appraisal Tool and a five-step integrative approach to analysis followed. FINDINGS: Eleven articles were identified, all quantitative in nature. It is clear that the general purpose of birth plans is communication, with decision making a key factor. Even though the processes of birth planning were varied, having a birth plan was associated with generally positive birth outcomes. CONCLUSIONS: Despite the heterogeneity of birth plans, birth plans were associated with positive outcomes for childbearing women when developed in collaboration with care providers. The act of collaboratively creating a birth plan may improve obstetric outcomes, aid realistic expectations, and improve satisfaction and the sense of control.


Asunto(s)
Servicios de Salud Materna , Femenino , Humanos , Parto , Embarazo , Atención Prenatal
19.
Cells ; 11(9)2022 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-35563695

RESUMEN

Understanding early nervous system stress response mechanisms is crucial for studying developmental neurotoxicity and devising neuroprotective treatments. We used hiPSC-derived long-term self-renewing neuroepithelial stem (lt-NES) cells differentiated for up to 12 weeks as an in vitro model of human neural development. Following a transcriptome analysis to identify pathway alterations, we induced acute oxidative stress (OS) using tert-butyl hydroperoxide (TBHP) and assessed cell viability at different stages of neural differentiation. We studied NRF2 activation, autophagy, and proteasomal function to explore the contribution and interplay of these pathways in the acute stress response. With increasing differentiation, lt-NES cells showed changes in the expression of metabolic pathway-associated genes with engagement of the pentose phosphate pathway after 6 weeks, this was accompanied by a decreased susceptibility to TBHP-induced stress. Microarray analysis revealed upregulation of target genes of the antioxidant response KEAP1-NRF2-ARE pathway after 6 weeks of differentiation. Pharmacological inhibition of NRF2 confirmed its vital role in the increased resistance to stress. While autophagy was upregulated alongside differentiation, it was not further increased upon oxidative stress and had no effect on stress-induced cell loss and the activation of NRF2 downstream genes. In contrast, proteasome inhibition led to the aggravation of the stress response resulting in decreased cell viability, derangement of NRF2 and KEAP1 protein levels, and lacking NRF2-pathway activation. Our data provide detailed insight into the dynamic regulation and interaction of pathways involved in modulating stress responses across defined time points of neural differentiation.


Asunto(s)
Factor 2 Relacionado con NF-E2 , Sistema Nervioso , Proliferación Celular , Humanos , Células Madre Pluripotentes Inducidas , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Redes y Vías Metabólicas , Factor 2 Relacionado con NF-E2/metabolismo , Sistema Nervioso/metabolismo
20.
Animals (Basel) ; 11(6)2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34198636

RESUMEN

A key welfare concern for the equine population in the U.K. has been identified as delayed death, leading to prolonged suffering of horses. Reasons why some horse owners fail to have their horses euthanised include financial cost, emotional attachment, peer pressure, negative attitudes towards killing and poor recognition of behavioural indicators of equine pain and stress. The Five Freedoms framework of welfare was used to build a Likert-style survey to investigate the factors underlying attitudes of horse owners towards welfare measures in an end-of-life decision. Participants were asked to respond to hypothetical welfare scenarios and to give details of any horses they had had euthanised. The survey was conducted predominantly via equestrian Facebook groups and obtained 160 participant responses. Reliability of the scale was acceptable, with Cronbach's α=0.89. Principal Component Analysis was used to load the hypothetical scenarios onto seven factors containing 62.2% of the variance. The first four factors could be categorized according to "Ethology-informed Management", "Traditional Horse Management", "Emotional Issues" and "Physical Issues". Participants were more likely to consider euthanasia for physical issues, compared with issues relating to affective state and/or ethology, although it was not clear whether this was due to disregard for welfare issues relating to mental health or failure to recognise them as such. A large number of responses stated that the scenario had no bearing on whether a horse should be euthanised, again suggesting a lack of recognition of welfare issues and their implications. When asked to state their reasons for euthanising their horses, participants cited almost exclusively physical reasons, with the exception of those citing dangerous behaviour. Only a small number of responses also included consideration of affective and/or ethological factors, suggesting that welfare issues concerning affective state and/or behaviour are at risk of omission from end-of-life decisions.

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