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1.
Small ; : e2304850, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38686680

RESUMO

Silver has long been recognized for its potent antimicrobial properties, but achieving a slow and longer-term delivery of silver ions presents significant challenges. Previous efforts to control silver ion dosages have struggled to sustain release for extended periods in biomimetic environments, especially in the presence of complex proteins. This challenge is underscored by the absence of technology for sustaining antimicrobial activity, especially in the context of orthopedic implants where long-term efficacy, extending beyond 7 days, is essential. In this study, the tunable, slow, and longer-term release of silver ions from the two-dimensional (2D) nanocapillaries of graphene oxide (GO) laminates incorporated with silver ions (Ag-GO) for antimicrobial applications are successfully demonstrated. To closely mimic a physiologically relevant serum-based environment, a novel in vitro study model using 100% fetal bovine serum (FBS) is introduced as the test medium for microbiology, biocompatibility, and bioactivity studies. To emulate fluid circulation in a physiological environment, the in vitro studies are challenged with serum exchange protocols on different days. The findings show that the Ag-GO coating can sustainably release silver ions at a minimum dosage of 10 µg cm-2 day-1, providing an effective and sustained antimicrobial barrier for over ten days.

2.
Fam Pract ; 40(2): 273-281, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36250448

RESUMO

BACKGROUND: Mental health needs of transgender individuals can be complex with individual, social, and medical factors impacting symptoms. This study examines predictors of mood or anxiety problems among transgender individuals seeking hormone therapy (HT). METHODS: A retrospective chart review was conducted at 2 clinics providing gender-affirming HT. Cross-sectional data from initial patient encounters (N = 311) were used in this study. Bivariate correlations and multiple logistic regression analyses were carried out. RESULTS: Transgender women (TW) were 2.2 times more likely to have mood or anxiety problems while transgender men (TM) were 2.6 times more likely as the number of medical comorbidities increased. For both TW and TM, White race significantly increased the likelihood of mood or anxiety problems. Neither previous nor current HT were associated with mood or anxiety problems for TW and TM. However, receiving multiple gender-affirming procedures decreased the likelihood of mood or anxiety problems for TM. CONCLUSIONS: Gender-affirming care and addressing comorbidities can be important aspects of mental health needs for transgender individuals.


The majority of transgender men and women reported 1 or more chronic health conditions. These health conditions were associated with transgender individuals being more likely to have a mood or anxiety problem. Currently receiving or previously receiving hormonal therapy was not associated with mood or anxiety problems for transgender men or women, but having received 1 or multiple gender-affirming procedures was associated with a decrease in likelihood of having a mood or anxiety problem for transgender men. White race also was associated with increased likelihood of having a mood or anxiety problem for transgender men and women. These results highlight the need for primary care physicians to take a comprehensive approach when dealing with the mental health needs of transgender patients by ensuring that general health care needs are met while receiving gender-affirming care.


Assuntos
Pessoas Transgênero , Masculino , Humanos , Feminino , Pessoas Transgênero/psicologia , Estudos Retrospectivos , Estudos Transversais , Ansiedade/epidemiologia , Hormônios
3.
J Nerv Ment Dis ; 211(12): 981-984, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38015191

RESUMO

ABSTRACT: COVID-19 has led to marked increases in healthcare worker distress. Studies of these phenomena are often limited to a particular element of distress or a specific subset of healthcare workers. We administered the Moral Injury Symptom Scale for Healthcare Professionals, Copenhagen Burnout Inventory, Patient Health Questionnaire-9, and Generalized Anxiety Disorder-7 via online survey to 17,000 employees of a large academic medical center between December 2021 and February 2022. A total of 1945 participants completed the survey. Across all roles, the prevalence of moral injury, burnout, depression, and anxiety were 40.9%, 35.3%-60.6%, 25.4%, and 24.8%, respectively. Furthermore, 8.1% had been bothered by thoughts that they would be better off dead or of hurting themselves for "several days" or more frequently. Healthcare workers across all roles and practice settings are experiencing unsustainable levels of distress, with 1 in 12 regularly experiencing thoughts of self-harm.


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Prevalência , Depressão/epidemiologia , Pandemias , COVID-19/epidemiologia , Transtornos de Ansiedade/epidemiologia , Ansiedade/epidemiologia , Esgotamento Psicológico , Pessoal de Saúde
4.
Anaerobe ; 80: 102717, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36871786

RESUMO

OBJECTIVES: The objective of the study was to explore antimicrobial resistance gene determinant, and phenotypic antibiotic susceptibility, data for Fusobacterium necrophorum from a collection of UK strains. Antimicrobial resistance genes detected in publicly available assembled whole genome sequences were investigated for comparison. METHODS: Three hundred and eighty five F. necrophorum strains (1982-2019) were revived from cryovials (Prolab). Subsequent to sequencing (Illumina) and quality checking, 374 whole genomes were available for analysis. Genomes were interrogated, using BioNumerics (bioMérieux; v 8.1), for the presence of known antimicrobial resistance genes (ARGs). Agar dilution susceptibility results for 313 F. necrophorum isolates (2016-2021) were also examined. RESULTS: The phenotypic data for the 313 contemporary strains demonstrated potential resistance to penicillin in three isolates, using EUCAST v 11.0 breakpoints, and 73 (23%) strains using v 13.0 analysis. All strains were susceptible to multiple agents using v 11.0 guidance other than clindamycin (n = 2). Employing v 13.0 breakpoints, metronidazole (n = 3) and meropenem (n = 13) resistance were also detected. The tet(O), tet(M), tet(40), aph(3')-III, ant(6)-la and blaOXA-85 ARGs were present in publicly available genomes. tet(M), tet(32), erm(A) and erm(B) were found within the UK strains, with correspondingly raised clindamycin and tetracycline minimum inhibitory concentrations. CONCLUSIONS: Susceptibility to antibiotics recommended for the treatment of F. necrophorum infections should not be assumed. With evidence of potential ARG transmission from oral bacteria, and the detection of a transposon-mediated beta-lactamase resistance determinant in F. necrophorum, surveillance of both phenotypic and genotypic antimicrobial susceptibility trends must continue, and increase.


Assuntos
Clindamicina , Fusobacterium necrophorum , Antibacterianos/farmacologia , Tetraciclina , Penicilinas , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana
5.
Plant Physiol ; 187(4): 2110-2125, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618095

RESUMO

Two decades ago, large cation currents were discovered in the envelope membranes of Pisum sativum L. (pea) chloroplasts. The deduced K+-permeable channel was coined fast-activating chloroplast cation channel but its molecular identity remained elusive. To reveal candidates, we mined proteomic datasets of isolated pea envelopes. Our search uncovered distant members of the nuclear POLLUX ion channel family. Since pea is not amenable to molecular genetics, we used Arabidopsis thaliana to characterize the two gene homologs. Using several independent approaches, we show that both candidates localize to the chloroplast envelope membrane. The proteins, designated PLASTID ENVELOPE ION CHANNELS (PEC1/2), form oligomers with regulator of K+ conductance domains protruding into the intermembrane space. Heterologous expression of PEC1/2 rescues yeast mutants deficient in K+ uptake. Nuclear POLLUX ion channels cofunction with Ca2+ channels to generate Ca2+ signals, critical for establishing mycorrhizal symbiosis and root development. Chloroplasts also exhibit Ca2+ transients in the stroma, probably to relay abiotic and biotic cues between plastids and the nucleus via the cytosol. Our results show that pec1pec2 loss-of-function double mutants fail to trigger the characteristic stromal Ca2+ release observed in wild-type plants exposed to external stress stimuli. Besides this molecular abnormality, pec1pec2 double mutants do not show obvious phenotypes. Future studies of PEC proteins will help to decipher the plant's stress-related Ca2+ signaling network and the role of plastids. More importantly, the discovery of PECs in the envelope membrane is another critical step towards completing the chloroplast ion transport protein inventory.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Membranas Intracelulares/metabolismo , Canais Iônicos/genética , Pisum sativum/genética , Pisum sativum/metabolismo , Plastídeos/genética , Proteínas de Arabidopsis/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Filogenia , Proteômica
6.
Plant Physiol ; 186(1): 142-167, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33779763

RESUMO

During photosynthesis, electrons travel from light-excited chlorophyll molecules along the electron transport chain to the final electron acceptor nicotinamide adenine dinucleotide phosphate (NADP) to form NADPH, which fuels the Calvin-Benson-Bassham cycle (CBBC). To allow photosynthetic reactions to occur flawlessly, a constant resupply of the acceptor NADP is mandatory. Several known stromal mechanisms aid in balancing the redox poise, but none of them utilizes the structurally highly similar coenzyme NAD(H). Using Arabidopsis (Arabidopsis thaliana) as a C3-model, we describe a pathway that employs the stromal enzyme PHOSPHOGLYCERATE DEHYDROGENASE 3 (PGDH3). We showed that PGDH3 exerts high NAD(H)-specificity and is active in photosynthesizing chloroplasts. PGDH3 withdrew its substrate 3-PGA directly from the CBBC. As a result, electrons become diverted from NADPH via the CBBC into the separate NADH redox pool. pgdh3 loss-of-function mutants revealed an overreduced NADP(H) redox pool but a more oxidized plastid NAD(H) pool compared to wild-type plants. As a result, photosystem I acceptor side limitation increased in pgdh3. Furthermore, pgdh3 plants displayed delayed CBBC activation, changes in nonphotochemical quenching, and altered proton motive force partitioning. Our fluctuating light-stress phenotyping data showed progressing photosystem II damage in pgdh3 mutants, emphasizing the significance of PGDH3 for plant performance under natural light environments. In summary, this study reveals an NAD(H)-specific mechanism in the stroma that aids in balancing the chloroplast redox poise. Consequently, the stromal NAD(H) pool may provide a promising target to manipulate plant photosynthesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , NAD , Fosfoglicerato Desidrogenase , Fotossíntese , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , NAD/metabolismo , Fosfoglicerato Desidrogenase/metabolismo
7.
Plant Cell ; 31(8): 1845-1855, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31217220

RESUMO

Chloroplasts evolved from a cyanobacterial endosymbiont that resided within a eukaryotic cell. Due to their prokaryotic heritage, chloroplast outer membranes contain transmembrane ß-barrel proteins. While most chloroplast proteins use N-terminal transit peptides to enter the chloroplasts through the translocons at the outer and inner chloroplast envelope membranes (TOC/TIC), only one ß-barrel protein, Toc75, has been shown to use this pathway. The route other ß-barrel proteins use has remained unresolved. Here we use in vitro pea (Pisum sativum) chloroplast import assays and transient expression in Nicotiana benthamiana to address this. We show that a paralog of Toc75, outer envelope protein 80 kD (OEP80), also uses a transit peptide but has a distinct envelope sorting signal. Our results additionally indicate that ß-barrels that do not use transit peptides also enter the chloroplast using components of the general import pathway.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Cloroplastos/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transporte Proteico/genética , Transporte Proteico/fisiologia , Nicotiana/genética , Nicotiana/metabolismo
8.
J Adv Nurs ; 78(12): 4190-4198, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35909094

RESUMO

AIMS: This research aimed to identify the factors that impact why men do not view nursing as a career choice. DESIGN: Qualitative description was utilized to capture the rich narratives and insight of participants. METHODS: Through convenience sampling, nine New Zealand qualified male nurses within their first three years of practice were recruited. Semi-structured interviews were conducted between November 2019 and January 2020 via zoom from sites across New Zealand. All interviews were recorded and transcribed, with the data analysed using Braun and Clarke's thematic analysis. RESULTS: The findings reflected the experiences of the research participants as they made sense of a predominantly female-dominated work environment both during their undergraduate training and prior to recruitment. The research identified two key themes: The first found that men in nursing experienced isolation due to the societal gendering of nursing influencing the participant's knowledge and understanding of what nursing was, as a career. The second theme found that for participants, nursing was not prominent in their awareness when leaving school and making career choices. CONCLUSION: This research indicates that nursing as a career choice for men is still underpinned by a lack of understanding of the actual role of the nurse and what nurses do, and is more supported by a societal perception that nursing is still a feminized profession. Findings can be used to make recommendations for change in the profession to strengthen diversity in the workforce and redefine the recruitment of men into nursing. IMPACT: This research reviewed the career choices of men in nursing and why they chose nursing as a profession. Understanding the barriers of why men do not consider nursing as a career choice assists with finding strategies in both the clinical and academic environments that can enable greater gender diversity within the nursing profession. NO PATIENT OR PUBLIC CONTRIBUTION: This applies to this research as the focus was on male registered nurses only.


Assuntos
Escolha da Profissão , Estudantes , Humanos , Masculino , Feminino , Pesquisa Qualitativa , Recursos Humanos , Nova Zelândia
9.
J Med Ethics ; 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290114

RESUMO

After 40 years of attributing high rates of physician career dissatisfaction, attrition, alcoholism, divorce and suicide to 'burnout', there is growing recognition that these outcomes may instead be caused by moral injury. This has led to a debate about the relative diagnostic merits of these two terms, a recognition that interventions designed to treat burnout may be ineffective, and much perplexity about how-if at all-this changes anything.The current research seeks to develop the construct of moral injury outside military contexts, generate more robust validity tests and more fully describe and measure the experiences of persons exposed to moral harms. Absent from the literature is a mechanism through which to move from the collective moral injury experience of physicians to a systematic change in the structure of medical practice. To address this, after providing a brief history, definitions and contrasts between burnout, moral distress and moral injury, we review the interplay of moral and ethical codes in the context of moral injury. We conclude by suggesting that professional associations can potentially prevent moral injury by providing protections for physicians within their codes of ethics.

10.
Metabolomics ; 16(10): 107, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026554

RESUMO

INTRODUCTION: It is widely but erroneously believed that drugs get into cells by passing through the phospholipid bilayer portion of the plasma and other membranes. Much evidence shows, however, that this is not the case, and that drugs cross biomembranes by hitchhiking on transporters for other natural molecules to which these drugs are structurally similar. Untargeted metabolomics can provide a method for determining the differential uptake of such metabolites. OBJECTIVES: Blood serum contains many thousands of molecules and provides a convenient source of biologically relevant metabolites. Our objective was to detect and identify metabolites present in serum, but to also establish a method capable of measure their uptake and secretion by different cell lines. METHODS: We develop an untargeted LC-MS/MS method to detect a broad range of compounds present in human serum. We apply this to the analysis of the time course of the uptake and secretion of metabolites in serum by several human cell lines, by analysing changes in the serum that represents the extracellular phase (the 'exometabolome' or metabolic footprint). RESULTS: Our method measures some 4000-5000 metabolic features in both positive and negative electrospray ionisation modes. We show that the metabolic footprints of different cell lines differ greatly from each other. CONCLUSION: Our new, 15-min untargeted metabolome method allows for the robust and convenient measurement of differences in the uptake of serum compounds by cell lines following incubation in serum. This will enable future research to study these differences in multiple cell lines that will relate this to transporter expression, thereby advancing our knowledge of transporter substrates, both natural and xenobiotic compounds.


Assuntos
Metabolômica/métodos , Plasma/química , Animais , Linhagem Celular/metabolismo , Linhagem Celular Tumoral/metabolismo , Membrana Celular/metabolismo , Cromatografia Líquida/métodos , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Humanos , Mamíferos/metabolismo , Proteínas de Membrana/metabolismo , Metaboloma , Fosfolipídeos/metabolismo , Espectrometria de Massas em Tandem/métodos
11.
Microbiology (Reading) ; 165(4): 439-454, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30741628

RESUMO

Rapid changes in the number and flow cytometric behaviour of cells of E. coli taken from a stationary phase and inoculated into rich medium.Cells of E. coli were grown in LB medium, taken from a stationary phase of 2-4 h, and re-inoculated into fresh media at a concentration (105 ml-1 or lower) characteristic of bacteriuria. Flow cytometry was used to assess how quickly we could detect changes in cell size, number, membrane energization (using a carbocyanine dye) and DNA distribution. It transpired that while the lag phase observable macroscopically via bulk OD measurements could be as long as 4 h, the true lag phase could be less than 15-20 min, and was accompanied by many observable biochemical changes. Antibiotics to which the cells were sensitive affected these changes within 20 min of re-inoculation, providing the possibility of a very rapid antibiotic susceptibility test on a timescale compatible with a visit to a GP clinic. The strategy was applied successfully to genuine potential urinary tract infection (UTI) samples taken from a doctor's surgery. The methods developed could prove of considerable value in ensuring the correct prescription and thereby lowering the spread of antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Citometria de Fluxo , Testes de Sensibilidade Microbiana/métodos , Infecções Urinárias/microbiologia , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Bacteriúria/tratamento farmacológico , Bacteriúria/microbiologia , Meios de Cultura , Humanos , Infecções Urinárias/tratamento farmacológico
12.
Clin Chem ; 65(1): 170-179, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30518663

RESUMO

BACKGROUND: For transgender individuals taking hormone therapy (HT), data on laboratory values are limited, and the effects on laboratory values cannot be easily predicted. We evaluated the impact on common laboratory analytes in transgender individuals before and after initiation of HT. METHODS: We conducted a retrospective chart review of transgender patients identified at transgender-specific clinics at an urban county hospital and community clinic. Laboratory data were collected on hormone concentrations, hematologic parameters, electrolytes, lipids, and liver and renal markers before and after initiation of HT. RESULTS: We identified 183 transgender women (TW) and 119 transgender men (TM) for whom laboratory data were available. In all, 87 TW and 62 TM had baseline laboratory data, and data were also available for 133 TW and 89 TM on HT for >6 months. The most significant changes were seen in red blood cell count, hemoglobin concentration, hematocrit, and creatinine levels after >6 months of HT, which increased in TM and decreased in TW after HT (P < 0.005; d index > 0.6). Alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase levels increased in TM; however, the effect size was small (d index < 0.5). Calcium, albumin, and alkaline phosphatase levels significantly decreased in TW (P < 0.001; d > 0.6). Additionally, TM were found to have increased triglycerides and decreased HDL levels (P < 0.005; d > 0.6). CONCLUSIONS: Changes occur in several common laboratory parameters for patients on HT. Some laboratory values changed to match the gender identity, whereas others remained unchanged or were intermediate from the baseline values. These findings will help guide interpretation of laboratory test results in transgender patients taking HT.


Assuntos
Técnicas de Laboratório Clínico , Terapia de Reposição Hormonal , Pessoas Transgênero , Adulto , Feminino , Testes Hematológicos , Humanos , Testes de Função Renal , Testes de Função Hepática , Masculino , Estudos Retrospectivos
13.
BMC Microbiol ; 19(1): 195, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438868

RESUMO

BACKGROUND: It is widely believed that most xenobiotics cross biomembranes by diffusing through the phospholipid bilayer, and that the use of protein transporters is an occasional adjunct. According to an alternative view, phospholipid bilayer transport is negligible, and several different transporters may be involved in the uptake of an individual molecular type. We recognise here that the availability of gene knockout collections allows one to assess the contributions of all potential transporters, and flow cytometry based on fluorescence provides a convenient high-throughput assay for xenobiotic uptake in individual cells. RESULTS: We used high-throughput flow cytometry to assess the ability of individual gene knockout strains of E coli to take up two membrane-permeable, cationic fluorescent dyes, namely the carbocyanine diS-C3(5) and the DNA dye SYBR Green. Individual strains showed a large range of distributions of uptake. The range of modal steady-state uptakes for the carbocyanine between the different strains was 36-fold. Knockouts of the ATP synthase α- and ß-subunits greatly inhibited uptake, implying that most uptake was ATP-driven rather than being driven by a membrane potential. Dozens of transporters changed the steady-state uptake of the dye by more than 50% with respect to that of the wild type, in either direction (increased or decreased); knockouts of known influx and efflux transporters behaved as expected, giving credence to the general strategy. Many of the knockouts with the most reduced uptake were transporter genes of unknown function ('y-genes'). Similarly, several overexpression variants in the 'ASKA' collection had the anticipated, opposite effects. Similar results were obtained with SYBR Green (the range being approximately 69-fold). Although it too contains a benzothiazole motif there was negligible correlation between its uptake and that of the carbocyanine when compared across the various strains (although the membrane potential is presumably the same in each case). CONCLUSIONS: Overall, we conclude that the uptake of these dyes may be catalysed by a great many transporters of putatively broad and presently unknown specificity, and that the very large range between the 'lowest' and the 'highest' levels of uptake, even in knockouts of just single genes, implies strongly that phospholipid bilayer transport is indeed negligible. This work also casts serious doubt upon the use of such dyes as quantitative stains for representing either bioenergetic parameters or the amount of cellular DNA in unfixed cells (in vivo). By contrast, it opens up their potential use as transporter assay substrates in high-throughput screening.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Corantes Fluorescentes/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Benzotiazóis/química , Benzotiazóis/metabolismo , Transporte Biológico , Carbocianinas/química , Carbocianinas/metabolismo , Diaminas , Escherichia coli/química , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Citometria de Fluxo , Corantes Fluorescentes/química , Proteínas de Membrana Transportadoras/genética , Compostos Orgânicos/química , Compostos Orgânicos/metabolismo , Quinolinas
14.
Biochem Biophys Res Commun ; 495(2): 2010-2016, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29248726

RESUMO

An authenticated U87MG clonal glioblastoma cell line was investigated to identify a sub-population of neurospheroidal (NSP) cells within the main epithelial population (U87MG). The NSP cells sorted using Fluorescence Assisted Cell Sorting (FACS) showed varied morphology, 30% lower growth rates, 40% higher IC50 values for temozolomide drug and could differentiate into the glial cell type (NDx). Metabolite profiling using HR-LCMS identified glucose, glutamine and serine in both populations and tryptophan only in U87MG as growth limiting substrates. Glycine, alanine, glutamate and proline were secreted by U87MG, however proline and glycine were re-utilized in NSP. Exo-metabolite profiling and phenotypic microarrays identified differential metabolism of primary carbon sources glucose and derived pyruvate for U87MG; glutamine and derived glutamate metabolism in NSP. Differential mRNA abundance of AKT1, PTEN, PIK3CA controlling metabolism, drug efflux, nutrient transport and epigenetic control MDM2 are potentially critical in shaping DNA methylation effects of temozolomide. Our study provides a new insight into the combined effect of these factors leading to temozolomide resistance in NSP.


Assuntos
Aminoácidos/metabolismo , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glucose/metabolismo , Análise do Fluxo Metabólico/métodos , Ácido Pirúvico/metabolismo , Antineoplásicos Alquilantes/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/administração & dosagem , Relação Dose-Resposta a Droga , Glioblastoma/patologia , Humanos , Integração de Sistemas , Temozolomida
15.
Bioinformatics ; 33(23): 3784-3792, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036627

RESUMO

MOTIVATION: In recent years, there has been great progress in the field of automated curation of biomedical networks and models, aided by text mining methods that provide evidence from literature. Such methods must not only extract snippets of text that relate to model interactions, but also be able to contextualize the evidence and provide additional confidence scores for the interaction in question. Although various approaches calculating confidence scores have focused primarily on the quality of the extracted information, there has been little work on exploring the textual uncertainty conveyed by the author. Despite textual uncertainty being acknowledged in biomedical text mining as an attribute of text mined interactions (events), it is significantly understudied as a means of providing a confidence measure for interactions in pathways or other biomedical models. In this work, we focus on improving identification of textual uncertainty for events and explore how it can be used as an additional measure of confidence for biomedical models. RESULTS: We present a novel method for extracting uncertainty from the literature using a hybrid approach that combines rule induction and machine learning. Variations of this hybrid approach are then discussed, alongside their advantages and disadvantages. We use subjective logic theory to combine multiple uncertainty values extracted from different sources for the same interaction. Our approach achieves F-scores of 0.76 and 0.88 based on the BioNLP-ST and Genia-MK corpora, respectively, making considerable improvements over previously published work. Moreover, we evaluate our proposed system on pathways related to two different areas, namely leukemia and melanoma cancer research. AVAILABILITY AND IMPLEMENTATION: The leukemia pathway model used is available in Pathway Studio while the Ras model is available via PathwayCommons. Online demonstration of the uncertainty extraction system is available for research purposes at http://argo.nactem.ac.uk/test. The related code is available on https://github.com/c-zrv/uncertainty_components.git. Details on the above are available in the Supplementary Material. CONTACT: sophia.ananiadou@manchester.ac.uk. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Mineração de Dados/métodos , Aprendizado de Máquina , Incerteza , Publicações
16.
Photosynth Res ; 138(3): 315-326, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30291507

RESUMO

Chloroplasts are descendants of an ancient endosymbiotic cyanobacterium that lived inside a eukaryotic cell. They inherited the prokaryotic double membrane envelope from cyanobacteria. This envelope contains prokaryotic protein sorting machineries including a Sec translocase and relatives of the central component of the bacterial outer membrane ß-barrel assembly module. As the endosymbiont was integrated with the rest of the cell, the synthesis of most of its proteins shifted from the stroma to the host cytosol. This included nearly all the envelope proteins identified so far. Consequently, the overall biogenesis of the chloroplast envelope must be distinct from cyanobacteria. Envelope proteins initially approach their functional locations from the exterior rather than the interior. In many cases, they have been shown to use components of the general import pathway that also serves the stroma and thylakoids. If the ancient prokaryotic protein sorting machineries are still used for chloroplast envelope proteins, their activities must have been modified or combined with the general import pathway. In this review, we analyze the current knowledge pertaining to chloroplast envelope biogenesis and compare this to bacteria.


Assuntos
Evolução Biológica , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Modelos Biológicos , Transporte Proteico
19.
Nat Methods ; 10(11): 1063-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24173381

RESUMO

Two surveys of over 1,700 publications whose authors use quantitative real-time PCR (qPCR) reveal a lack of transparent and comprehensive reporting of essential technical information. Reporting standards are significantly improved in publications that cite the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines, although such publications are still vastly outnumbered by those that do not.


Assuntos
Serviços de Informação , Reação em Cadeia da Polimerase/métodos , Coleta de Dados
20.
Nucleic Acids Res ; 42(Web Server issue): W395-400, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24782527

RESUMO

GeneGenie, a new online tool available at http://www.gene-genie.org, is introduced to support the design and self-assembly of synthetic genes and constructs. GeneGenie allows for the design of oligonucleotide cohorts encoding the gene sequence optimized for expression in any suitable host through an intuitive, easy-to-use web interface. The tool ensures consistent oligomer overlapping melting temperatures, minimizes the likelihood of misannealing, optimizes codon usage for expression in a selected host, allows for specification of forward and reverse cloning sequences (for downstream ligation) and also provides support for mutagenesis or directed evolution studies. Directed evolution studies are enabled through the construction of variant libraries via the optional specification of 'variant codons', containing mixtures of bases, at any position. For example, specifying the variant codon TNT (where N is any nucleotide) will generate an equimolar mixture of the codons TAT, TCT, TGT and TTT at that position, encoding a mixture of the amino acids Tyr, Ser, Cys and Phe. This facility is demonstrated through the use of GeneGenie to develop and synthesize a library of enhanced green fluorescent protein variants.


Assuntos
Evolução Molecular Direcionada/métodos , Genes Sintéticos , Oligonucleotídeos/química , Software , Algoritmos , Códon , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Internet , Análise de Sequência de Proteína
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