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1.
Nat Chem Biol ; 18(11): 1184-1195, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36163383

RESUMO

Although cyclophilins are attractive targets for probing biology and therapeutic intervention, no subtype-selective cyclophilin inhibitors have been described. We discovered novel cyclophilin inhibitors from the in vitro selection of a DNA-templated library of 256,000 drug-like macrocycles for cyclophilin D (CypD) affinity. Iterated macrocycle engineering guided by ten X-ray co-crystal structures yielded potent and selective inhibitors (half maximal inhibitory concentration (IC50) = 10 nM) that bind the active site of CypD and also make novel interactions with non-conserved residues in the S2 pocket, an adjacent exo-site. The resulting macrocycles inhibit CypD activity with 21- to >10,000-fold selectivity over other cyclophilins and inhibit mitochondrial permeability transition pore opening in isolated mitochondria. We further exploited S2 pocket interactions to develop the first cyclophilin E (CypE)-selective inhibitor, which forms a reversible covalent bond with a CypE S2 pocket lysine, and exhibits 30- to >4,000-fold selectivity over other cyclophilins. These findings reveal a strategy to generate isoform-selective small-molecule cyclophilin modulators, advancing their suitability as targets for biological investigation and therapeutic development.


Assuntos
Ciclofilinas , Poro de Transição de Permeabilidade Mitocondrial , Ciclofilinas/química , Ciclofilinas/metabolismo , Peptidil-Prolil Isomerase F , Lisina , DNA
2.
J Strength Cond Res ; 38(3): 549-555, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38088926

RESUMO

ABSTRACT: McNeill, C, Beaven, CM, McMaster, DT, Ward, P, and Gill, N. Eccentric force-velocity-load relationship in trained rugby union athletes. J Strength Cond Res 38(3): 549-555, 2024-The force-velocity relationship is traditionally believed to resemble a hyperbolic shape, known as the "force-velocity curve." However, there is less evidence regarding this relationship during eccentric muscle action in multijoint isotonic exercise, especially in applied settings. The purpose of this study was to investigate the force-velocity-load relationship in an incremental eccentric back squat test. In addition, 37 professional male rugby union athletes were recruited to participate. Separate generalized linear mixed models were used to analyze the effect of barbell load on relative eccentric peak force (REPF), relative eccentric mean force (REMF), eccentric peak velocity (EPV), and eccentric mean velocity (EMV). A significant effect of load ( p < 0.05) was observed for each of the eccentric variables tested. Each increase in barbell load tended to result in a linear increase in REMF and a decrease in EMV and EPV; however, we observed a plateauing effect for REPF as load increased. These results show that for "peak" variables lighter loads produced similar magnitudes of force, but generally moved at higher velocities than heavier loads. These observations suggest that the eccentric force-velocity-load relationship may vary depending on the parameters used. Quantifying rapid, multijoint eccentric performance is justified as it seems to provide valuable insight into individual athletic capability and training program design. Further research may investigate the responsiveness of the qualities to training and the causal nature of eccentric characteristics and athletic performance.


Assuntos
Desempenho Atlético , Treinamento Resistido , Humanos , Masculino , Força Muscular/fisiologia , Rugby , Treinamento Resistido/métodos , Músculo Esquelético/fisiologia , Atletas , Desempenho Atlético/fisiologia
3.
Am J Epidemiol ; 192(2): 257-266, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36222700

RESUMO

Surveillance of drug overdose deaths relies on death certificates for identification of the substances that caused death. Drugs and drug classes can be identified through the International Classification of Diseases, Tenth Revision (ICD-10), codes present on death certificates. However, ICD-10 codes do not always provide high levels of specificity in drug identification. To achieve more fine-grained identification of substances on death certificate, the free-text cause-of-death section, completed by the medical certifier, must be analyzed. Current methods for analyzing free-text death certificates rely solely on lookup tables for identifying specific substances, which must be frequently updated and maintained. To improve identification of drugs on death certificates, a deep-learning named-entity recognition model was developed, utilizing data from the Kentucky Drug Overdose Fatality Surveillance System (2014-2019), which achieved an F1-score of 99.13%. This model can identify new drug misspellings and novel substances that are not present on current surveillance lookup tables, enhancing the surveillance of drug overdose deaths.


Assuntos
Atestado de Óbito , Overdose de Drogas , Humanos , Kentucky/epidemiologia , Classificação Internacional de Doenças
4.
J Pathol ; 257(2): 198-217, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35107828

RESUMO

SARS-CoV-2, the causative agent of COVID-19, typically manifests as a respiratory illness, although extrapulmonary involvement, such as in the gastrointestinal tract and nervous system, as well as frequent thrombotic events, are increasingly recognised. How this maps onto SARS-CoV-2 organ tropism at the histological level, however, remains unclear. Here, we perform a comprehensive validation of a monoclonal antibody against the SARS-CoV-2 nucleocapsid protein (NP) followed by systematic multisystem organ immunohistochemistry analysis of the viral cellular tropism in tissue from 36 patients, 16 postmortem cases and 16 biopsies with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 status from the peaks of the pandemic in 2020 and four pre-COVID postmortem controls. SARS-CoV-2 anti-NP staining in the postmortem cases revealed broad multiorgan involvement of the respiratory, digestive, haematopoietic, genitourinary and nervous systems, with a typical pattern of staining characterised by punctate paranuclear and apical cytoplasmic labelling. The average time from symptom onset to time of death was shorter in positively versus negatively stained postmortem cases (mean = 10.3 days versus mean = 20.3 days, p = 0.0416, with no cases showing definitive staining if the interval exceeded 15 days). One striking finding was the widespread presence of SARS-CoV-2 NP in neurons of the myenteric plexus, a site of high ACE2 expression, the entry receptor for SARS-CoV-2, and one of the earliest affected cells in Parkinson's disease. In the bone marrow, we observed viral SARS-CoV-2 NP within megakaryocytes, key cells in platelet production and thrombus formation. In 15 tracheal biopsies performed in patients requiring ventilation, there was a near complete concordance between immunohistochemistry and PCR swab results. Going forward, our findings have relevance to correlating clinical symptoms with the organ tropism of SARS-CoV-2 in contemporary cases as well as providing insights into potential long-term complications of COVID-19. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Megacariócitos , Plexo Mientérico , Neurônios
5.
Nucleic Acids Res ; 49(D1): D1541-D1547, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33174596

RESUMO

The mammalian mitochondrial proteome is under dual genomic control, with 99% of proteins encoded by the nuclear genome and 13 originating from the mitochondrial DNA (mtDNA). We previously developed MitoCarta, a catalogue of over 1000 genes encoding the mammalian mitochondrial proteome. This catalogue was compiled using a Bayesian integration of multiple sequence features and experimental datasets, notably protein mass spectrometry of mitochondria isolated from fourteen murine tissues. Here, we introduce MitoCarta3.0. Beginning with the MitoCarta2.0 inventory, we performed manual review to remove 100 genes and introduce 78 additional genes, arriving at an updated inventory of 1136 human genes. We now include manually curated annotations of sub-mitochondrial localization (matrix, inner membrane, intermembrane space, outer membrane) as well as assignment to 149 hierarchical 'MitoPathways' spanning seven broad functional categories relevant to mitochondria. MitoCarta3.0, including sub-mitochondrial localization and MitoPathway annotations, is freely available at http://www.broadinstitute.org/mitocarta and should serve as a continued community resource for mitochondrial biology and medicine.


Assuntos
Bases de Dados de Proteínas , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Anotação de Sequência Molecular , Proteoma/metabolismo , Animais , Teorema de Bayes , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Conjuntos de Dados como Assunto , Humanos , Internet , Aprendizado de Máquina , Espectrometria de Massas , Camundongos , Mitocôndrias/genética , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/classificação , Proteínas Mitocondriais/genética , Proteoma/classificação , Proteoma/genética , Software
6.
Eur J Anaesthesiol ; 40(11): 826-832, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37646501

RESUMO

BACKGROUND: Guidelines from the Obstetric Anaesthetists' Association and Difficult Airway Society state that 'a videolaryngoscope should be immediately available for all obstetric general anaesthetics'. OBJECTIVE: To report the incidence of videolaryngoscopy use, and other airway management safety interventions, in an obstetric population before and after various quality improvement interventions. DESIGN: Prospective data collection was undertaken over 18 months, divided into three separate 6-month periods: June to November 2019; March to August 2021; January to June 2022. These periods relate to evaluation of specific quality improvement interventions. SETTING: The project was carried out in a large tertiary referral obstetric unit. PATIENTS: We identified 401 pregnant women (> 20 weeks' gestation) and postnatal women (up to 48 h post delivery) undergoing an obstetric surgical procedure under general anaesthesia. INTERVENTIONS: To standardise practice, an intubation checklist was introduced in December 2020 and multidisciplinary staff training in August 2021. MAIN OUTCOME MEASURES: Primary outcome measures were use of a Macintosh-style videolaryngoscope and tracheal intubation success. Secondary outcome measures were use of an intubation checklist; low flow nasal oxygen; and ramped patient positioning. RESULTS: Data from 334 tracheal intubations (83.3% of cases) were recorded. Videolaryngoscope use increased from 60% in 2019, to 88% in 2021, to 94% in 2022. Tracheal intubation was successful in all patients, with 94% first pass success overall and only 0.9% requiring three attempts. Use of secondary outcome measures also increased: low flow nasal oxygen from 48% in 2019 to 90% in 2022; ramped positioning from 95% in 2021 to 97% in 2022; and checklist use from 63% in 2021 to 92% in 2022. CONCLUSIONS: We describe the successful adoption of simple safety measures introduced into routine practice. These comprised videolaryngoscopy, ramped positioning and low flow nasal oxygen. Their introduction was supported by the implementation of an intubation checklist and multidisciplinary team training.


Assuntos
Laringoscópios , Laringoscopia , Humanos , Feminino , Gravidez , Laringoscopia/efeitos adversos , Laringoscopia/métodos , Melhoria de Qualidade , Intubação Intratraqueal/métodos , Manuseio das Vias Aéreas/efeitos adversos , Manuseio das Vias Aéreas/métodos , Oxigênio
7.
BMC Plant Biol ; 22(1): 73, 2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35183130

RESUMO

BACKGROUND: Chitosan has shown potential for the control of Fusarium head blight (FHB) disease caused by Fusarium graminearum. The objective of this study was to compare the effect of chitosan hydrochloride applied pre- or post-fungal inoculation on FHB and to better understand its' mode of action via an untargeted metabolomics study. RESULTS: Chitosan inhibited fungal growth in vitro and, when sprayed on the susceptible wheat cultivar Remus 24 hours pre-inoculation with F. graminearum, it significantly reduced the number of infected spikelets at 7, 14 and 21 days post-inoculation. Chitosan pre-treatment also increased the average grain weight per head, the number of grains per head and the 1000-grain weight compared to the controls sprayed with water. No significant impact of chitosan on grain yield was observed when the plants were sprayed 24 hours post-inoculation with F. graminearum, even if it did result in a reduced number of infected spikelets at every time point. An untargeted metabolomic study using UHPLC-QTOF-MS on wheat spikes revealed that spraying the spikes with both chitosan and F. graminearum activated known FHB resistance pathways (e.g. jasmonic acid). Additionally, more metabolites were up- or down-regulated when both chitosan and F. graminearum spores were sprayed on the spikes (117), as compared with chitosan (51) or F. graminearum on their own (32). This included a terpene, a terpenoid and a liminoid previously associated with FHB resistance. CONCLUSIONS: In this study we showed that chitosan hydrochloride inhibited the spore germination and hyphal development of F. graminearum in vitro, triggered wheat resistance against infection by F. graminearum when used as a pre-inoculant, and highlighted metabolites and pathways commonly and differentially affected by chitosan, the pathogen and both agents. This study provides insights into how chitosan might provide protection or stimulate wheat resistance to infection by F. graminearum. It also unveiled new putatively identified metabolites that had not been listed in previous FHB or chitosan-related metabolomic studies.


Assuntos
Quitosana/farmacologia , Fusarium/efeitos dos fármacos , Doenças das Plantas/microbiologia , Triticum/efeitos dos fármacos , Triticum/microbiologia , Cromatografia Líquida de Alta Pressão , Ciclopentanos/metabolismo , Fungicidas Industriais/farmacologia , Fusarium/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Espectrometria de Massas , Metaboloma , Oxilipinas/metabolismo , Triticum/metabolismo
8.
Breast Cancer Res Treat ; 192(1): 153-161, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35112166

RESUMO

BACKGROUND: The NSABP B-36 compared four cycles of doxorubicin and cyclophosphamide (AC) with six cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC-100) in node-negative early-stage breast cancer. A sub-study within B-36, focusing on symptoms, quality of life (QOL), menstrual history (MH), and cardiac function (CF) was conducted. PATIENTS AND METHODS: Patients completed the QOL questionnaire at baseline, during treatment, and every 6 months through 36 months. FACT-B Trial Outcome Index (TOI), symptom severity, and SF-36 Vitality and Physical Functioning (PF) scales scores were compared between the two groups using a mixed model for repeated measures analysis. MH was collected at baseline and subsequently assessed if menstrual bleeding occurred within 12 months prior to randomization. Post-chemotherapy amenorrhea outcome was examined at 18 months and was defined as lack of menses in the preceding year. Logistic regression was used to test for association of amenorrhea and treatment. CF assessment was done at baseline and 12 months. Correlation analysis was used to address associations between changes in baseline and 12-month PF and concurrent CF changes measured by LVEF. RESULTS: FEC-100 patients had statistically significantly lower TOI scores during chemotherapy (P = 0.02) and at 6 months (P < 0.001); lower Vitality score at 6 months (P < 0.01), and lower PF score during the first year than AC patients. There were no statistically significant QOL score differences between the two groups beyond 12 months. No significant differences in symptom severity between the two groups were observed. Rates of amenorrhea were significantly different between FEC-100 and AC (67.4% vs. 59.1%, P < 0.001). There was no association between changes in LVEF and PF (P = 0.38). CONCLUSIONS: Statistically significant QOL differences between the two groups favored AC; however, the magnitude was small and unlikely to be clinically meaningful. There was a clinical and statistically significant difference in risk for amenorrhea, favoring AC. TRIAL REGISTRY: NCT00087178; Date of registration: 07/08/2004.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Epirubicina/efeitos adversos , Feminino , Fluoruracila/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida
9.
Breast Cancer Res Treat ; 193(3): 555-564, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35230585

RESUMO

PURPOSE: Results from adjuvant trials evaluating 6 cycles of epirubicin-based chemotherapy regimens suggested these programs may be more effective than 4 cycles of doxorubicin-based chemotherapy. METHOD: NSABP B-36 was a phase III clinical trial originally designed as a 2 × 2 factorial study comparing 6 cycles of 5-FU, epirubicin, and cyclophosphamide (FEC-100) to 4 cycles of conventional doxorubicin and cyclophosphamide (AC) with celecoxib or placebo. Shortly after activation, concerns regarding increased cardiovascular risks among selective COX-2 inhibitors resulted in a decision to remove the celecoxib/placebo from the trial. Women with histologically node-negative invasive breast cancer who had undergone primary surgery with a lumpectomy or total mastectomy were eligible. Primary endpoint was disease-free survival (DFS). RESULTS: Between May 2004 and July 2008, 2722 patients were enrolled. Administration of FEC-100 did not result in improvement in DFS compared to AC (HR 1.09; 95% CI 0.92-1.29, p value = 0.31). The effect of FEC-100 compared to AC on DFS was significantly different for receptor-positive (HR 1.32, 95% CI 1.05-1.66) compared to receptor-negative patients (HR 0.86, 95% CI 0.66-1.11) (treatment-by-receptor status interaction p value = 0.02). There was no statistically significant difference in the effect of treatment on overall survival (OS) with FEC-100 compared to AC (HR 1.06; 95% CI 0.84-1.35, p value = 0.61). Overall, Grade 3 and 4 adverse events were more frequent in the FEC-100 group. CONCLUSION: The results of B-36 do not support use of six-cycle anthracycline-based regimens in node-negative breast cancer. Prolongation of anthracycline-based therapy with FEC-100 does not improve DFS or OS, relative to AC for 4 cycles, and was associated with expected increases in toxicity. A statistically significant interaction between treatment and hormone receptor status favoring AC in hormone-receptor-positive breast cancers is consistent with the hypothesis that optimal duration of chemotherapy may be four cycles in these patients. Late cardiac events and deaths prior to recurrence or second cancer were infrequent on both arms, but slightly higher with FEC-100. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00087178.


Assuntos
Neoplasias da Mama , Antraciclinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Celecoxib/uso terapêutico , Quimioterapia Adjuvante , Ciclofosfamida , Intervalo Livre de Doença , Doxorrubicina/efeitos adversos , Epirubicina , Feminino , Fluoruracila , Humanos , Mastectomia
10.
Clin Otolaryngol ; 47(1): 131-137, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606150

RESUMO

OBJECTIVES: This study examines the histological findings of tracheal tissue samples obtained from COVID-19 positive mechanically ventilated patients, to assess the degree of tracheal inflammation/ulceration present. DESIGN AND PARTICIPANTS: Retrospective single-centre observational cohort study. All patients admitted to Adult Intensive Care Unit (AICU) with COVID-19 infection, requiring mechanical ventilation and surgical tracheostomy between 1 April and 1 May 2020, were included (Group 1). Tracheal windows excised at tracheostomy underwent histological analysis. Comparison was made with: tracheal windows from COVID-19 positive AICU ventilated patients admitted between 1 January and 1 March 2021 (Group 2); tracheal windows from COVID-19 negative AICU ventilated patients (Group 3); and, tracheal autopsy samples from COVID-19 positive patients that died without undergoing prolonged mechanical ventilation (Group 4). RESULTS: Group 1 demonstrated mild/moderate inflammation (tracheitis) in nearly all samples (15/16, 93.8%), with infrequent micro-ulceration (2/16, 12.5%). Group 2 demonstrated similar mild/moderate inflammation in all samples (17/17, 100%), with no ulceration. Histological findings of Groups 1 and 2 COVID-19 positive patients were similar to Group 3 COVID-19 negative patients, which demonstrated mild/moderate inflammation (5/5, 100%), with uncommon superficial erosion (1/5, 20%). Group 4 demonstrated mild chronic inflammation or no significant inflammation, with uncommon micro-ulceration (1/4, 25%). CONCLUSIONS: Severe tracheal inflammation was not demonstrated in mechanically ventilated COVID-19 positive patients at the level of the second/third tracheal rings, at the stage of disease patients underwent tracheostomy. Histological findings were similar between mechanically ventilated COVID-19 positive and negative patients. Tracheal ulceration may be a feature of early or severe COVID-19 disease.


Assuntos
COVID-19/terapia , Pneumonia Viral/terapia , Respiração Artificial , Traqueia/lesões , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Unidades de Terapia Intensiva , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/virologia , Estudos Retrospectivos , SARS-CoV-2 , Traqueostomia
11.
Am J Public Health ; 111(10): 1851-1854, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34499540

RESUMO

Objectives. To examine trends in opioid overdose deaths by race/ethnicity from 2018 to 2019 across 67 HEALing Communities Study (HCS) communities in Kentucky, New York, Massachusetts, and Ohio. Methods. We used state death certificate records to calculate opioid overdose death rates per 100 000 adult residents of the 67 HCS communities for 2018 and 2019. We used Poisson regression to calculate the ratio of 2019 to 2018 rates. We compared changes by race/ethnicity by calculating a ratio of rate ratios (RRR) for each racial/ethnic group compared with non-Hispanic White individuals. Results. Opioid overdose death rates were 38.3 and 39.5 per 100 000 for 2018 and 2019, respectively, without a significant change from 2018 to 2019 (rate ratio = 1.03; 95% confidence interval [CI] = 0.98, 1.08). We estimated a 40% increase in opioid overdose death rate for non-Hispanic Black individuals (RRR = 1.40; 95% CI = 1.22, 1.62) relative to non-Hispanic White individuals but no change among other race/ethnicities. Conclusions. Overall opioid overdose death rates have leveled off but have increased among non-Hispanic Black individuals. Public Health Implications. An antiracist public health approach is needed to address the crisis of opioid-related harms. (Am J Public Health. 2021;111(10):1851-1854. https://doi.org/10.2105/AJPH.2021.306431).


Assuntos
Etnicidade/estatística & dados numéricos , Geografia Médica/estatística & dados numéricos , Overdose de Opiáceos/etnologia , Overdose de Opiáceos/mortalidade , Adulto , Bases de Dados Factuais/estatística & dados numéricos , Humanos , Kentucky , Massachusetts , New York , Ohio
12.
Genes Dev ; 27(18): 1974-85, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24065765

RESUMO

Somatic mutations in the isocitrate dehydrogenase (IDH) genes IDH1 and IDH2 occur frequently in acute myeloid leukemia (AML) and other cancers. These genes encode neomorphic proteins that produce the presumed oncometabolite 2-hydroxyglutarate (2-HG). Despite the prospect of treating AML and other cancers by targeting IDH mutant proteins, it remains unclear how these mutants affect tumor development and maintenance in vivo, and no cancer models exist to study the action of IDH2 mutants in vivo. We show that IDH2 mutants can cooperate with oncogenic Flt3 or Nras alleles to drive leukemia in mice by impairing the differentiation of cells of the myeloid lineage. Pharmacologic or genetic inhibition of IDH2 triggers the differentiation and death of AML cells, albeit only with prolonged IDH2 inhibition. In contrast, inhibition of the bromodomain-containing protein Brd4 triggers rapid differentiation and death of IDH2 mutant AML. Our results establish a critical role for mutant IDH2 in leukemogenesis and tumor maintenance and identify an IDH-independent strategy to target these cancers therapeutically.


Assuntos
Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Leucemia Mieloide Aguda/fisiopatologia , Mutação , Animais , Diferenciação Celular/genética , Transformação Celular Neoplásica , Células Cultivadas , Metilação de DNA/genética , Modelos Animais de Doenças , GTP Fosfo-Hidrolases/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/enzimologia , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tirosina Quinase 3 Semelhante a fms/metabolismo
13.
Genes Dev ; 27(18): 1986-98, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24065766

RESUMO

More than 50% of patients with chondrosarcomas exhibit gain-of-function mutations in either isocitrate dehydrogenase 1 (IDH1) or IDH2. In this study, we performed genome-wide CpG methylation sequencing of chondrosarcoma biopsies and found that IDH mutations were associated with DNA hypermethylation at CpG islands but not other genomic regions. Regions of CpG island hypermethylation were enriched for genes implicated in stem cell maintenance/differentiation and lineage specification. In murine 10T1/2 mesenchymal progenitor cells, expression of mutant IDH2 led to DNA hypermethylation and an impairment in differentiation that could be reversed by treatment with DNA-hypomethylating agents. Introduction of mutant IDH2 also induced loss of contact inhibition and generated undifferentiated sarcomas in vivo. The oncogenic potential of mutant IDH2 correlated with the ability to produce 2-hydroxyglutarate. Together, these data demonstrate that neomorphic IDH2 mutations can be oncogenic in mesenchymal cells.


Assuntos
Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/genética , Condrossarcoma/enzimologia , Condrossarcoma/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Mutação , Animais , Neoplasias Ósseas/fisiopatologia , Diferenciação Celular , Linhagem Celular , Condrossarcoma/fisiopatologia , Ilhas de CpG/genética , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma , Glutaratos/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/enzimologia , Camundongos , Camundongos Nus , Transplante Heterólogo
14.
J Fish Biol ; 98(3): 634-642, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33124691

RESUMO

Inadequately designed culverts can be physical barriers to fish passage if they increase the velocity of water flow in the environment, alter natural turbulence patterns or fail to provide adequate water depth. They may also act as behavioural barriers to fish passage if they affect the willingness of fish species to enter or pass through the structure due to altered ambient light conditions. To understand how reduced light intensity might affect fish behaviour in culverts, the authors performed a behavioural choice experiment quantifying the amount of time individual fish spent in dark and illuminated areas of a controlled experimental channel. They found that behavioural responses were largely reflective of the species' diel activity patterns; the diurnal species Craterocephalus stercusmuscarum and Retropinna semoni preferred illuminated regions, whereas the nocturnal/crepuscular Macquaria novemaculeata preferred the darkened region of the channel. Bidyanus bidyanus were strongly rheotactic, and their behaviour was influenced more by water flow direction than ambient light level. The authors then determined that a threshold light intensity of only c. 100-200 lx (cf. midday sunlight c. 100,000 lx) was required to overcome the behavioural barrier in c. 70% of the diurnally active C. stercusmuscarum and R. semoni tested. When these values were placed into an environmental context, 15 road-crossing (3.4-7.0 m long) box (c. 1 m × 1 m, height × width) and pipe (c. 1 m diameter) culverts sampled in Brisbane, Australia, recorded light intensities in the centre of the structure that were below the threshold for C. stercusmuscarum and R. semoni movement and could potentially be a barrier to their passage through the structure. Attention is required to better understand the impacts of low light intensity in culverts on fish passage and to prioritize restoration.


Assuntos
Aprendizagem da Esquiva/efeitos da radiação , Ecossistema , Peixes/fisiologia , Luz , Animais , Austrália , Comportamento de Escolha/efeitos da radiação
15.
J Sports Sci ; 38(7): 773-779, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32096452

RESUMO

This study investigated the association between talent selection criteria, draft order and match performance in professional Australian Football players. Physical performance results from the Australian Football League (AFL) National Draft combine and non-performance based talent selection criteria were collated for all players drafted in the National Draft with selections 1-80 between 2003 and 2008 (n = 318). Match performance was assessed via the AFL Player Ranking metric that was provided by a commercial statistical provider (Champion Data Pty Ltd). A combination of stepwise multiple regression and linear mixed model analyses examined the influence of National Draft combine physical performance assessments and non-performance based talent selection criteria on draft order and future match performance. Earlier draft selection was associated with Under-18 all Australian team selection, height, Under-18 National Championship participation and indigenous status. The 20 m sprint and state of origin were associated with later draft selection. Under-18 all Australian team selection increased both Player Ranking/game and total Player Ranking. Under-18 all Australian team selection displays efficacy for selecting players with the potential for success.


Assuntos
Aptidão , Desempenho Atlético , Destreza Motora , Esportes , Adolescente , Humanos , Masculino , Austrália , Estudos Longitudinais , Estudos Retrospectivos
16.
J Biol Chem ; 293(52): 20051-20061, 2018 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-30381394

RESUMO

Monoallelic point mutations in the gene encoding the cytosolic, NADP+-dependent enzyme isocitrate dehydrogenase 1 (IDH1) cause increased production of the oncometabolite 2-hydroxyglutarate (2-HG) in multiple cancers. Most IDH1 mutant tumors retain one wildtype (WT) IDH1 allele. Several studies have proposed that retention of this WT allele is protumorigenic by facilitating substrate channeling through a WT-mutant IDH1 heterodimer, with the WT subunit generating a local supply of α-ketoglutarate and NADPH that is then consumed by the mutant subunit to produce 2-HG. Here, we confirmed that coexpression of WT and mutant IDH1 subunits leads to formation of WT-mutant hetero-oligomers and increases 2-HG production. An analysis of a recently reported crystal structure of the WT-R132H IDH1 heterodimer and of in vitro kinetic parameters for 2-HG production, however, indicated that substrate channeling between the subunits is biophysically implausible. We also found that putative carbon-substrate flux between WT and mutant IDH1 subunits is inconsistent with the results of isotope tracing experiments in cancer cells harboring an endogenous monoallelic IDH1 mutation. Finally, using a mathematical model of WT-mutant IDH1 heterodimers, we estimated that the NADPH:NADP+ ratio is higher in the cytosol than in the mitochondria, suggesting that NADPH is unlikely to be limiting for 2-HG production in the cytosol. These findings argue against supply of either substrate being limiting for 2-HG production by a cytosolic IDH1 mutant and suggest that the retention of a WT allele in IDH1 mutant tumors is not due to a requirement for carbon or cofactor flux between WT and mutant IDH1.


Assuntos
Hidroxibutiratos/metabolismo , Isocitrato Desidrogenase , Modelos Biológicos , Mutação , Proteínas de Neoplasias , Neoplasias , Linhagem Celular Tumoral , Células HEK293 , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , NADP/genética , NADP/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Multimerização Proteica
17.
Oncologist ; 24(12): e1409-e1416, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31420467

RESUMO

BACKGROUND: This randomized, double-blinded, phase II trial evaluated the efficacy of carboplatin and pemetrexed plus either apatorsen, an antisense oligonucleotide targeting heat shock protein (Hsp) 27 mRNA, or placebo in patients with previously untreated metastatic nonsquamous non-small cell lung cancer (NSCLC). METHODS: Patients were randomized 1:1 to Arm A (carboplatin/pemetrexed plus apatorsen) or Arm B (carboplatin/pemetrexed plus placebo). Treatment was administered in 21-day cycles, with restaging every two cycles, until progression or intolerable toxicity. Serum Hsp27 levels were analyzed at baseline and during treatment. The primary endpoint was progression-free survival (PFS); secondary endpoints included overall survival (OS), objective response rate, and toxicity. RESULTS: The trial enrolled 155 patients (median age 66 years; 44% Eastern Cooperative Oncology Group performance status 0). Toxicities were similar in the 2 treatment arms; cytopenias, nausea, vomiting, and fatigue were the most frequent treatment-related adverse events. Median PFS and OS were 6.0 and 10.8 months, respectively, for Arm A, and 4.9 and 11.8 months for Arm B (differences not statistically significant). Overall response rates were 27% for Arm A and 32% for Arm B. Sixteen patients (12%) had high serum levels of Hsp27 at baseline. In this small group, patients who received apatorsen had median PFS of 10.8 months, and those who received placebo had median PFS 4.8 months. CONCLUSION: The addition of apatorsen to carboplatin and pemetrexed was well tolerated but did not improve outcomes in patients with metastatic nonsquamous NSCLC cancer in the first-line setting. IMPLICATIONS FOR PRACTICE: This randomized, double-blinded, phase II trial evaluated the efficacy of carboplatin and pemetrexed plus either apatorsen, an antisense oligonucleotide targeting heat shock protein 27 mRNA, or placebo in patients with previously untreated metastatic nonsquamous non-small cell lung cancer (NSCLC). The addition of apatorsen to carboplatin and pemetrexed was well tolerated but did not improve outcomes in patients with metastatic nonsquamous NSCLC cancer in the first-line setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Oligonucleotídeos/uso terapêutico , Pemetrexede/uso terapêutico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carboplatina/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Estadiamento de Neoplasias , Oligonucleotídeos/farmacologia , Pemetrexede/farmacologia
18.
BMC Microbiol ; 19(1): 175, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362696

RESUMO

BACKGROUND: Over a one year period, swabs of 820 beef carcasses were tested for the presence of Shiga toxin-producing Escherichia coli by performing Polymerase Chain Reaction (PCR) in a novel technology termed "cassette PCR", in comparison to conventional liquid PCR. Cassette PCR is inexpensive and ready-to-use. The operator need only add the sample and press "go". Cassette PCR can simultaneously test multiple samples for multiple targets. Carcass swab samples were first tested for the presence of STEC genes (O157, eae, stx1 and stx2). Samples were considered to be pathogenic if positive for eae plus stx1 and/or stx2. For samples scored as pathogenic, further testing screened for 6 additional high frequency O-antigens (O26, O45, O103, O111, O121, and O145). RESULTS: Of the 820 samples, 41% were pathogenic and 30% were O157 positive. Of these, 19% of samples were positive for O157 and carried potentially pathogenic E. coli (eae plus stx1 and/or stx2). Of all samples identified as carrying pathogenic E. coli, 18.9, 38.8, 41.4, 0, 36.1, and 4.1% respectively were positive for O26, O45, O103, O111, O121, and O145. To validate cassette PCR testing, conventional PCR using STEC primers was performed on each of the 820 samples. Only 148 of 3280 cassette PCR tests were discordant with conventional PCR results. However, further fractional testing showed that 110 of these 148 PCRs reflected low numbers of E. coli in the enrichment broth and could be explained as due to Poisson limiting dilution of the template, affecting both cassette PCR and conventional PCR. Of the remaining 38 discordant tests, 27 initial capillary PCRs and 10 initial conventional tests were nominally discordant between cassette and conventional PCR, perhaps reflecting human/technical error on both sides of the comparison. CONCLUSIONS: Contaminated beef carcass swabs were often complex, likely harboring more than one strain of pathogenic E. coli. Cassette PCR had 98.8% concordance with parallel conventional PCR for detection of STEC genes. This indicates that cassette PCR is highly reliable for detecting multiple pathogens in beef carcass swabs from processing plants.


Assuntos
Proteínas de Escherichia coli/genética , Reação em Cadeia da Polimerase Multiplex , Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Adesinas Bacterianas/genética , Animais , Bovinos , Infecções por Escherichia coli , Microbiologia de Alimentos/métodos , Genes Bacterianos , Antígenos O/genética , Carne Vermelha/toxicidade , Toxina Shiga I/genética , Toxina Shiga II/genética , Escherichia coli Shiga Toxigênica/genética
19.
Inorg Chem ; 58(9): 5561-5575, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30950603

RESUMO

The copper-based metal-organic framework (MOF) HKUST-1 adsorbs organic molecules into its pores. When loaded with electron-rich oligothiophenes, the resulting system reacts under heat to initiate oxidative polymerization without the use of any other oxidant or catalyst. This reaction is not observed in the non-redox-active MOF MIL-100(Al). We have characterized the composites by optical and nanoscale microscopy, vibrational and UV-vis spectroscopy, X-ray photoelectron spectroscopy, N2 sorption analysis, and thermogravimetric analysis/residual gas analysis. Unsubstituted oligothiophenes polymerize within MOF pores, while 3,4-ethylenedioxythiophene forms a coating on the MOF surface. MOF composites with conjugated polymer dopants trapped inside their pores undergo profound shifts in the composite electronic structure. Reasoning from time-dependent density functional theory calculations of an HKUST-1 model system bound to monomers, we rationalize the observed reactivity and propose an initiation mechanism based on a ligand-to-metal charge-transfer state.

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