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1.
Nature ; 565(7740): 460-463, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30626965

RESUMO

The accretion of hydrogen onto a white dwarf star ignites a classical nova eruption1,2-a thermonuclear runaway in the accumulated envelope of gas, leading to luminosities up to a million times that of the Sun and a high-velocity mass ejection that produces a remnant shell (mainly consisting of insterstellar medium). Close to the upper mass limit of a white dwarf3 (1.4 solar masses), rapid accretion of hydrogen (about 10-7 solar masses per year) from a stellar companion leads to frequent eruptions on timescales of years4,5 to decades6. Such binary systems are known as recurrent novae. The ejecta of recurrent novae, initially moving at velocities of up to 10,000 kilometres per second7, must 'sweep up' the surrounding interstellar medium, creating cavities in space around the nova binary. No remnant larger than one parsec across from any single classical or recurrent nova eruption is known8-10, but thousands of successive recurrent nova eruptions should be capable of generating shells hundreds of parsecs across. Here we report that the most frequently recurring nova, M31N 2008-12a in the Andromeda galaxy (Messier 31 or NGC 224), which erupts annually11, is indeed surrounded by such a super-remnant with a projected size of at least 134 by 90 parsecs. Larger than almost all known remnants of even supernova explosions12, the existence of this shell demonstrates that the nova M31N 2008-12a has erupted with high frequency for millions of years.

2.
Mol Cell Proteomics ; 22(2): 100485, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36549590

RESUMO

The molecular chaperone heat shock protein 90 (HSP90) works in concert with co-chaperones to stabilize its client proteins, which include multiple drivers of oncogenesis and malignant progression. Pharmacologic inhibitors of HSP90 have been observed to exert a wide range of effects on the proteome, including depletion of client proteins, induction of heat shock proteins, dissociation of co-chaperones from HSP90, disruption of client protein signaling networks, and recruitment of the protein ubiquitylation and degradation machinery-suggesting widespread remodeling of cellular protein complexes. However, proteomics studies to date have focused on inhibitor-induced changes in total protein levels, often overlooking protein complex alterations. Here, we use size-exclusion chromatography in combination with mass spectrometry (SEC-MS) to characterize the early changes in native protein complexes following treatment with the HSP90 inhibitor tanespimycin (17-AAG) for 8 h in the HT29 colon adenocarcinoma cell line. After confirming the signature cellular response to HSP90 inhibition (e.g., induction of heat shock proteins, decreased total levels of client proteins), we were surprised to find only modest perturbations to the global distribution of protein elution profiles in inhibitor-treated HT29 cells at this relatively early time-point. Similarly, co-chaperones that co-eluted with HSP90 displayed no clear difference between control and treated conditions. However, two distinct analysis strategies identified multiple inhibitor-induced changes, including known and unknown components of the HSP90-dependent proteome. We validate two of these-the actin-binding protein Anillin and the mitochondrial isocitrate dehydrogenase 3 complex-as novel HSP90 inhibitor-modulated proteins. We present this dataset as a resource for the HSP90, proteostasis, and cancer communities (https://www.bioinformatics.babraham.ac.uk/shiny/HSP90/SEC-MS/), laying the groundwork for future mechanistic and therapeutic studies related to HSP90 pharmacology. Data are available via ProteomeXchange with identifier PXD033459.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Humanos , Proteoma/metabolismo , Adenocarcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Proteínas de Choque Térmico HSP90 , Chaperonas Moleculares , Antineoplásicos/farmacologia , Espectrometria de Massas , Cromatografia em Gel
3.
Cells Tissues Organs ; 212(5): 383-398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36966531

RESUMO

Varying degrees of hydroxyapatite (HA) surface functionalization have been implicated as the primary driver of differential osteogenesis observed in infiltrating cells. The ability to reliably create spatially controlled areas of mineralization in composite engineered tissues is of growing interest in the field, and the use of HA-functionalized biomaterials may provide a robust solution to this challenge. In this study, we successfully fabricated polycaprolactone salt-leached scaffolds with two levels of a biomimetic calcium phosphate coating to examine their effects on MSC osteogenesis. Longer duration coating in simulated body fluid (SBF) led to increased HA crystal nucleation within scaffold interiors as well as more robust HA crystal formation on scaffold surfaces. Ultimately, the increased surface stiffness of scaffolds coated in SBF for 7 days in comparison to scaffolds coated in SBF for 1 day led to more robust osteogenesis of MSCs in vitro without the assistance of osteogenic signaling molecules. This study also demonstrated that the use of SBF-based HA coatings can promote higher levels of osteogenesis in vivo. Finally, when incorporated as the endplate region of a larger tissue-engineered intervertebral disc replacement, HA coating did not induce mineralization in or promote cell migration out of neighboring biomaterials. Overall, these results verified tunable biomimetic HA coatings as a promising biomaterial modification to promote discrete regions of mineralization within composite engineered tissues.


Assuntos
Materiais Biocompatíveis , Osseointegração , Engenharia Tecidual/métodos , Osteogênese , Durapatita/química , Alicerces Teciduais/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
4.
Anal Chem ; 94(29): 10320-10328, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35848328

RESUMO

Complete, reproducible extraction of protein material is essential for comprehensive and unbiased proteome analyses. A current gold standard is single-pot, solid-phase-enhanced sample preparation (SP3), in which organic solvent and magnetic beads are used to denature and capture protein aggregates, with subsequent washes removing contaminants. However, SP3 is dependent on effective protein immobilization onto beads, risks losses during wash steps, and exhibits losses and greater costs at higher protein inputs. Here, we propose solvent precipitation SP3 (SP4) as an alternative to SP3 protein cleanup, capturing acetonitrile-induced protein aggregates by brief centrifugation rather than magnetism─with optional low-cost inert glass beads to simplify handling. SP4 recovered equivalent or greater protein yields for 1-5000 µg preparations and improved reproducibility (median protein R2 0.99 (SP4) vs 0.97 (SP3)). Deep proteome profiling revealed that SP4 yielded a greater recovery of low-solubility and transmembrane proteins than SP3, benefits to aggregating protein using 80 vs 50% organic solvent, and equivalent recovery by SP4 and S-Trap. SP4 was verified in three other labs across eight sample types and five lysis buffers─all confirming equivalent or improved proteome characterization vs SP3. With near-identical recovery, this work further illustrates protein precipitation as the primary mechanism of SP3 protein cleanup and identifies that magnetic capture risks losses, especially at higher protein concentrations and among more hydrophobic proteins. SP4 offers a minimalistic approach to protein cleanup that provides cost-effective input scalability, the option to omit beads entirely, and suggests important considerations for SP3 applications─all while retaining the speed and compatibility of SP3.


Assuntos
Proteoma , Proteômica , Fenômenos Magnéticos , Agregados Proteicos , Proteoma/análise , Reprodutibilidade dos Testes , Solventes
5.
Dis Colon Rectum ; 65(1): 16-26, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34636780

RESUMO

BACKGROUND: Combined treatment modality of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is emerging as an alternative option for colorectal peritoneal metastases, but there is ambiguity regarding patient selection, treatment protocols, and efficacy. OBJECTIVE: To elaborate on the patient characteristics, hyperthermic intraperitoneal chemotherapy protocol and health outcomes in colorectal peritoneal metastases patients undergoing a combination of hyperthermic intraperitoneal chemotherapy and cytoreductive surgery and provide guidance for future studies. DATA SOURCES: A Medline search for English language studies published between 2004 and 2019. STUDY SELECTION: Medical subject headings and key terms, including: hyperthermic intraperitoneal chemotherapy, colorectal peritoneal metastases, colorectal cancer and combinations thereof as per guidelines. MAIN OUTCOME MEASURES: Overall survival, disease-free survival, and morbidity and mortality rates. RESULTS: Of the 26 included studies, 42% were published between 2016 and 2019. More than half of the studies were retrospective in nature and conducted in tertiary specialized centers outside of the United States. The median age range was 44 to 62 years. Mitomycin C-based therapy was seen in 50% of studies. Mean weighted median disease-free survival for 11 studies was 15 months (9 to 36 months). Median OS ranged from 12 to 63 months, with an average of 33.6 months among 20 studies. Overall morbidity varied from 11% to 56%, with a weighted mean of 29% in 18 studies. Mortality ranged from 0 to 34%, with a weighted mean of 4% in 15 studies. LIMITATIONS: Despite careful study selection, variability in methodology of the included studies can limit review findings. CONCLUSION: Due to study heterogeneity, and a recent large, randomized trial showing no overall benefit, use of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy in colorectal peritoneal metastases patients is highly controversial. Further standardized controlled studies can help uniformly define and build consensus among the medical community on patient eligibility and the optimal hyperthermic intraperitoneal chemotherapy techniques. PROSPERO: Registered on March 3, 2020, CRD42020146942.


Assuntos
Neoplasias Colorretais/secundário , Procedimentos Cirúrgicos de Citorredução/métodos , Quimioterapia Intraperitoneal Hipertérmica/métodos , Metástase Neoplásica/terapia , Peritônio/patologia , Adulto , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/uso terapêutico , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/terapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/uso terapêutico , Morbidade/tendências , Mortalidade/tendências , Metástase Neoplásica/patologia , Avaliação de Resultados em Cuidados de Saúde , Peritônio/efeitos dos fármacos , Estudos Retrospectivos , Estados Unidos/epidemiologia
6.
BMC Pediatr ; 22(1): 212, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35436899

RESUMO

BACKGROUND: Risky media use in terms of accumulating too much time in front of screens and usage before bedtime in early childhood is linked to developmental delays, reduced sleep quality, and unhealthy media use in later childhood and adulthood. For this reason, we examine patterns of media use in pre-school children and the extent to which child and family characteristics contribute to media use during the COVID-19 pandemic. METHODS: A cross-sectional study of digital media use by Canadian preschool-aged children (mean age = 3.45, N = 316) was conducted at the start of the COVID-19 pandemic between April and August of 2020. Parents completed a questionnaire and 24-h recall diary in the context of an ongoing study of child digital media use. From these responses we estimated hours of average daily screen time, screen time in the past 24 h, average daily mobile device use, and media use before bedtime. Parents also answered questions about their child (i.e., age, sex, temperament), family characteristics (parental mediation style, parental screen time, education, income), and contextual features of the pandemic (ex., remote work, shared childcare). Daycare closures were directly assessed using a government website. RESULTS: Our results indicate that 64% of preschoolers used more than 2 h of digital media hours/day on average during the pandemic. A majority (56%) of children were also exposed to media within the hour before bedtime. Logistic and multinomial regressions revealed that child age and temperament, restrictive parental mediation, as well as parent digital media use, education, satisfaction with the division of childcare, remote work, and number of siblings and family income were all correlates of risky digital media use by preschoolers. CONCLUSIONS: Our results suggest widespread risky media use by preschoolers during the pandemic. Parenting practices that include using more restrictive mediation strategies may foster benefits in regulating young children's screen time.


Assuntos
COVID-19 , Pandemias , Adulto , COVID-19/epidemiologia , COVID-19/prevenção & controle , Canadá/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Humanos , Internet , Poder Familiar , Pais , Tempo de Tela
7.
J Anat ; 238(4): 986-998, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33205444

RESUMO

Intervertebral disc (IVD) degeneration and associated back pain place a significant burden on the population. IVD degeneration is a progressive cascade of cellular, compositional, and structural changes, which results in a loss of disc height, disorganization of extracellular matrix architecture, tears in the annulus fibrosus which may involve herniation of the nucleus pulposus, and remodeling of the bony and cartilaginous endplates (CEP). These changes to the IVD often occur concomitantly, across the entire motion segment from the disc subcomponents to the CEP and vertebral bone, making it difficult to determine the causal initiating factor of degeneration. Furthermore, assessments of the subcomponents of the IVD have been largely qualitative, with most studies focusing on a single attribute, rather than multiple adjacent IVD substructures. The objective of this study was to perform a multiscale and multimodal analysis of human lumbar motion segments across various length scales and degrees of degeneration. We performed multiple assays on every sample and identified several correlations between structural and functional measurements of disc subcomponents. Our results demonstrate that with increasing Pfirrmann grade there is a reduction in disc height and nucleus pulposus T2 relaxation time, in addition to alterations in motion segment macromechanical function, disc matrix composition and cellular morphology. At the cartilage endplate-vertebral bone interface, substantial remodeling was observed coinciding with alterations in micromechanical properties. Finally, we report significant relationships between vertebral bone and nucleus pulposus metrics, as well as between micromechanical properties of the endplate and whole motion segment biomechanical parameters, indicating the importance of studying IVD degeneration as a whole organ.


Assuntos
Degeneração do Disco Intervertebral/fisiopatologia , Disco Intervertebral/fisiopatologia , Vértebras Lombares/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Microtomografia por Raio-X
8.
Opt Express ; 29(21): 33602-33614, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809170

RESUMO

Quantum cascade lasers (QCLs) represent a most promising compact source at terahertz (THz) frequencies, but efficiency of their continuous wave (CW) operation still needs to be improved to achieve large-scale exploitation. Here, we demonstrate highly efficient operation of a subwavelength microcavity laser consisting of two evanescently coupled whispering gallery microdisk resonators. Exploiting a dual injection scheme for the laser cavity, single mode CW vertical emission at 3.3 THz is obtained at 10 K with 6.4 mA threshold current and 145 mW/A slope efficiency up to 320 µW emitted power measured in quasi-CW mode. The tuning of the laser emission directionality is also obtained by independently varying the pumping strength between the microdisks. By connecting the resonators through a suspended gold bridge, the laser out-coupling efficiency in the vertical direction is strongly enhanced. Owing to the high brightness, low-power consumption and CW operation, the proposed microcavity laser design could allow the realization of high-performance CW THz QCLs ready for massive parallelization.

9.
Phys Rev Lett ; 126(20): 207701, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110191

RESUMO

We report on ballistic Hall photovoltammetry as a contactless probe of localized spin excitations. Spins resonating in the near field of a two-dimensional electron system are shown to induce a long range electromotive force that we calculate. We use this coupling mechanism to detect the spin wave eigenmodes of a single ferromagnet of sub-100 nm size. The high sensitivity of this detection technique, 380 spins/sqrt[Hz], and its noninvasiveness present advantages for probing magnetization dynamics and spin transport.

10.
J Biol Chem ; 294(36): 13336-13343, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31320475

RESUMO

Dynamic control of thioredoxin (Trx) oxidoreductase activity is essential for balancing the need of cells to rapidly respond to oxidative/nitrosative stress and to temporally regulate thiol-based redox signaling. We have previously shown that cytokine stimulation of the respiratory epithelium induces a precipitous decline in cell S-nitrosothiol, which depends upon enhanced Trx activity and proteasome-mediated degradation of Txnip (thioredoxin-interacting protein). We now show that tumor necrosis factor-α-induced Txnip degradation in A549 respiratory epithelial cells is regulated by the extracellular signal-regulated protein kinase (ERK) mitogen-activated protein kinase pathway and that ERK inhibition augments both intracellular reactive oxygen species and S-nitrosothiol. ERK-dependent Txnip ubiquitination and proteasome degradation depended upon phosphorylation of a PXTP motif threonine (Thr349) located within the C-terminal α-arrestin domain and proximal to a previously characterized E3 ubiquitin ligase-binding site. Collectively, these findings demonstrate the ERK mitogen-activated protein kinase pathway to be integrally involved in regulating Trx oxidoreductase activity and that the regulation of Txnip lifetime via ERK-dependent phosphorylation is an important mediator of this effect.


Assuntos
Proteínas de Transporte/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo , Células A549 , Humanos , Espectrometria de Massas , Células Tumorais Cultivadas
11.
Basic Res Cardiol ; 115(3): 26, 2020 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-32146560

RESUMO

Mesenchymal stromal cells (MSCs) exhibit antiapoptotic and proangiogenic functions in models of myocardial infarction which may be mediated by secreted small extracellular vesicles (sEVs). However, MSCs have frequently been harvested from aged or diseased patients, while the isolated sEVs often contain high levels of impurities. Here, we studied the cardioprotective and proangiogenic activities of size-exclusion chromatography-purified sEVs secreted from human foetal amniotic fluid stem cells (SS-hAFSCs), possessing superior functional potential to that of adult MSCs. We demonstrated for the first time that highly pure (up to 1.7 × 1010 particles/µg protein) and thoroughly characterised SS-hAFSC sEVs protect rat hearts from ischaemia-reperfusion injury in vivo when administered intravenously prior to reperfusion (38 ± 9% infarct size reduction, p < 0.05). SS-hAFSC sEVs did not protect isolated primary cardiomyocytes in models of simulated ischaemia-reperfusion injury in vitro, indicative of indirect cardioprotective effects. SS-hAFSC sEVs were not proangiogenic in vitro, although they markedly stimulated endothelial cell migration. Additionally, sEVs were entirely responsible for the promigratory effects of the medium conditioned by SS-hAFSC. Mechanistically, sEV-induced chemotaxis involved phosphatidylinositol 3-kinase (PI3K) signalling, as its pharmacological inhibition in treated endothelial cells reduced migration by 54 ± 7% (p < 0.001). Together, these data indicate that SS-hAFSC sEVs have multifactorial beneficial effects in a myocardial infarction setting.


Assuntos
Líquido Amniótico/citologia , Cardiotônicos/metabolismo , Movimento Celular , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Quimiotaxia , Humanos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Ratos , Traumatismo por Reperfusão/patologia
12.
Osteoporos Int ; 31(7): 1333-1340, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32112118

RESUMO

Among older adults who have recently sustained a fracture, there is substantial adoption of mobile technology. Furthermore, health and eHealth literacy level reported by participants supports the development of interactive eHealth interventions toward fostering better patient engagement in skeletal health management. INTRODUCTION: Electronic health resources are increasingly used in the self-management of medical conditions. We aimed to identify the current level of technology adoption, health, and eHealth literacy among older adults with a recent fracture, to determine if the use of electronic interventions would be feasible and acceptable in this population. METHODS: Adults ≥ 50 years with recent fractures were invited to complete a self-administered survey composed of 21 questions, including an 8-item perceived eHealth literacy scale. RESULTS: A total of 401 participants completed the survey (women, 64%; ≥ 65 years, 59%; university education, 32%). Most participants reported no difficulty in reading printed health material (67%) and felt confident in filling out medical forms (65%). Younger age and higher levels of education were associated with higher health literacy. Most respondents (81%) owned at least one mobile device (smartphone, 49%; tablet, 45%). eHEALS scores were similar among men (29, IQR 24-32) and women (29, IQR 25-33), and between younger age group categories (50-64 years, 30; IQR 26-33; and 65-74 years, 29; IQR 25-32), but lower in the oldest age group (≥ 75 years, 24; IQR 21-29; p < 0.05). Compared with the youngest group, those ≥ 75 years had higher odds of an eHEALS < 26 (odds ratio, 4.2; 95% confidence interval 2.0-8.9) after adjusting for sex and education level. CONCLUSION: There is significant adoption of mobile technology among older adults. Health and eHealth literacy reported by this study population supports the development of interactive eHealth interventions toward fostering better patient engagement in skeletal health management.


Assuntos
Telemedicina , Adulto , Idoso , Canadá , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários , Tecnologia
13.
Mol Cell Proteomics ; 17(4): 776-791, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29367434

RESUMO

Chronic lymphocytic leukemia (CLL) is a heterogeneous B-cell cancer exhibiting a wide spectrum of disease courses and treatment responses. Molecular characterization of RNA and DNA from CLL cases has led to the identification of important driver mutations and disease subtypes, but the precise mechanisms of disease progression remain elusive. To further our understanding of CLL biology we performed isobaric labeling and mass spectrometry proteomics on 14 CLL samples, comparing them with B-cells from healthy donors (HDB). Of 8694 identified proteins, ∼6000 were relatively quantitated between all samples (q<0.01). A clear CLL signature, independent of subtype, of 544 significantly overexpressed proteins relative to HDB was identified, highlighting established hallmarks of CLL (e.g. CD5, BCL2, ROR1 and CD23 overexpression). Previously unrecognized surface markers demonstrated overexpression (e.g. CKAP4, PIGR, TMCC3 and CD75) and three of these (LAX1, CLEC17A and ATP2B4) were implicated in B-cell receptor signaling, which plays an important role in CLL pathogenesis. Several other proteins (e.g. Wee1, HMOX1/2, HDAC7 and INPP5F) were identified with significant overexpression that also represent potential targets. Western blotting confirmed overexpression of a selection of these proteins in an independent cohort. mRNA processing machinery were broadly upregulated across the CLL samples. Spliceosome components demonstrated consistent overexpression (p = 1.3 × 10-21) suggesting dysregulation in CLL, independent of SF3B1 mutations. This study highlights the potential of proteomics in the identification of putative CLL therapeutic targets and reveals a subtype-independent protein expression signature in CLL.


Assuntos
Linfócitos B/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas de Neoplasias/metabolismo , Humanos , Proteômica , Spliceossomos
14.
Instr Course Lect ; 69: 273-288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32017733

RESUMO

The frequency of use of "biologics," including platelet-rich plasma (PRP), bone morphogenetic protein (BMP), and stem cell therapies in the treatment of orthopaedic conditions has significantly increased over the past few decades. The use of PRP and stem cells has been proposed for a wide variety of conditions including knee and hip osteoarthritis (OA), tendon strains and tendinopathies, muscle strains, and acute and chronic soft-tissue injuries. It has also been proposed for use in the enhancement of healing during surgical treatments. BMP has seen use in promoting fracture union and spinal fusion and has been researched as an adjunct in other procedures as well. The current state of the literature in the use and support of these biologics is outlined here.


Assuntos
Proteínas Morfogenéticas Ósseas , Plasma Rico em Plaquetas , Células-Tronco , Humanos , Lesões dos Tecidos Moles , Tendinopatia
15.
Osteoporos Int ; 30(7): 1383-1394, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30937483

RESUMO

Little is known about post-acute care following hip fracture surgery. We investigated discharge destinations from surgical hospitals for nine Canadian provinces. We identified significant heterogeneity in discharge patterns across provinces suggesting different post-acute recovery pathways. Further work is required to determine the impact on patient outcomes and health system costs. INTRODUCTION: To examine discharge destinations by provinces in Canada, adjusting for patient, injury, and care characteristics. METHODS: We analyzed population-based hospital discharge abstracts from a national administrative database for community-dwelling patients who underwent hip fracture surgery between 2004 and 2012 in Canada. Discharge destination was categorized as rehabilitation, home, acute care, and continuing care. Multinomial logistic regression modeling compared proportions of discharge to rehabilitation, acute care, and continuing care versus home between each province and Ontario. Adjusted risk differences and risk ratios were estimated. RESULTS: Of 111,952 previously community-dwelling patients aged 65 years or older, 22.5% were discharged to rehabilitation, 31.6% to home, 27.0% to acute care, and 18.2% to continuing care, with significant variation across provinces (p < 0.001). The proportion of discharge to rehabilitation ranged from 2.4% in British Columbia to 41.0% in Ontario while the proportion discharged home ranged from 20.3% in Prince Edward Island to 52.2% in British Columbia. The proportion of discharge to acute care ranged from 15.2% in Ontario to 58.8% in Saskatchewan while the proportion discharged to continuing care ranged from 9.3% in Manitoba and Prince Edward Island to 22.9% in New Brunswick. Adjusting for hospital type changed the direction of the provincial effect on discharge to continuing care in two provinces, but statistical significance remained consistent with the primary analysis. CONCLUSIONS: Discharge destination from the surgical hospital after hip fracture is highly variable across nine Canadian provinces. Further work is required to determine the impact of this heterogeneity on patient outcomes and health system costs.


Assuntos
Fraturas do Quadril/reabilitação , Alta do Paciente/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Canadá , Continuidade da Assistência ao Paciente/organização & administração , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Bases de Dados Factuais , Feminino , Fixação de Fratura/métodos , Fixação de Fratura/reabilitação , Pesquisa sobre Serviços de Saúde/métodos , Fraturas do Quadril/cirurgia , Humanos , Vida Independente/estatística & dados numéricos , Masculino , Transferência de Pacientes/estatística & dados numéricos , Cuidados Pós-Operatórios/métodos , Cuidados Pós-Operatórios/estatística & dados numéricos
16.
Mol Cell Proteomics ; 16(3): 386-406, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28062796

RESUMO

Approximately 800,000 leukemia and lymphoma cases are diagnosed worldwide each year. Burkitt's lymphoma (BL) and chronic lymphocytic leukemia (CLL) are examples of contrasting B-cell cancers; BL is a highly aggressive lymphoid tumor, frequently affecting children, whereas CLL typically presents as an indolent, slow-progressing leukemia affecting the elderly. The B-cell-specific overexpression of the myc and TCL1 oncogenes in mice induce spontaneous malignancies modeling BL and CLL, respectively. Quantitative mass spectrometry proteomics and isobaric labeling were employed to examine the biology underpinning contrasting Eµ-myc and Eµ-TCL1 B-cell tumors. Additionally, the plasma proteome was evaluated using subproteome enrichment to interrogate biomarker emergence and the systemic effects of tumor burden. Over 10,000 proteins were identified (q<0.01) of which 8270 cellular and 2095 plasma proteins were quantitatively profiled. A common B-cell tumor signature of 695 overexpressed proteins highlighted ribosome biogenesis, cell-cycle promotion and chromosome segregation. Eµ-myc tumors overexpressed several methylating enzymes and underexpressed many cytoskeletal components. Eµ-TCL1 tumors specifically overexpressed ER stress response proteins and signaling components in addition to both subunits of the interleukin-5 (IL5) receptor. IL5 treatment promoted Eµ-TCL1 tumor proliferation, suggesting an amplification of IL5-induced AKT signaling by TCL1. Tumor plasma contained a substantial tumor lysis signature, most prominent in Eµ-myc plasma, whereas Eµ-TCL1 plasma contained signatures of immune-response, inflammation and microenvironment interactions, with putative biomarkers in early-stage cancer. These findings provide a detailed characterization of contrasting B-cell tumor models, identifying common and specific tumor mechanisms. Integrated plasma proteomics allowed the dissection of a systemic response and a tumor lysis signature present in early- and late-stage cancers, respectively. Overall, this study suggests common B-cell cancer signatures exist and illustrates the potential of the further evaluation of B-cell cancer subtypes by integrative proteomics.


Assuntos
Biomarcadores Tumorais/análise , Linfoma de Burkitt/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteômica/métodos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas/genética , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Linfoma de Burkitt/genética , Estresse do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Espectrometria de Massas/métodos , Camundongos , Camundongos Transgênicos
17.
Instr Course Lect ; 68: 305-316, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32032069

RESUMO

Elective lumbar surgery for common degenerative lumbar spine pathology has been consistently demonstrated to have excellent outcomes by multiple validated measures and improves patient quality of life. The rate of complication is low but not unavoidable; there is an increasing recognition of risk factors that can be mitigated to decrease complication rates. When complications occur, prompt recognition and management may minimize deleterious effects on patient outcome. There are considerations for identifying risk factors and, when possible, minimizing them and general strategies for identifying and managing common complications in lumbar spine surgery.


Assuntos
Vértebras Lombares/cirurgia , Fusão Vertebral , Procedimentos Cirúrgicos Eletivos , Humanos , Complicações Pós-Operatórias , Qualidade de Vida , Sistema de Registros , Resultado do Tratamento
18.
Clin Exp Allergy ; 48(6): 650-662, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29676834

RESUMO

BACKGROUND: Severe asthma affects quality of life; however, its impact on workplace productivity is poorly understood. OBJECTIVE: To compare workplace productivity-absenteeism and presenteeism-and impairment in daily activities in severe and non-severe asthma over time and identify characteristics associated with presenteeism in severe asthma. METHODS: The Severe Asthma Web-based Database is an ongoing observational registry from Australia, New Zealand and Singapore. At April 2017, 434 patients with severe asthma and 102 with non-severe asthma were enrolled (18-88 years; 59% female). Participants provided comprehensive clinical and questionnaire data at baseline and were followed-up every 6 months for 24 months. Absenteeism (percentage of time not at work), presenteeism (self-reported impairment at work) and impairment in daily activities outside work due to health problems in the last week were calculated. RESULTS: At baseline, 61.4% of participants with severe asthma and 66.2% with non-severe asthma under 65 years were employed. At younger ages (30-50 years), fewer severe asthma participants were employed (69% vs 100%). Presenteeism and impairment in daily activity were more frequently reported in severe asthma and in participants with poorer asthma control, poorer lung function and more past-year exacerbations (P < .01). Over time, deteriorating asthma control was associated with increasing presenteeism. Although absenteeism was not different between severe and non-severe asthma, worse asthma control was associated with absenteeism (P < .001). In participants with severe asthma, presenteeism was reported more frequently in those with poorer asthma control, poorer asthma-related quality of life and symptoms of depression or anxiety (P < .01). CONCLUSION AND CLINICAL RELEVANCE: Severe asthma was associated with impairment at work and outside the workplace. Improving asthma control and mental health may be important targets for optimizing workplace productivity in severe asthma. Presenteeism and absenteeism may represent key metrics for assessing intervention efficacy in people with severe asthma of working age.


Assuntos
Absenteísmo , Asma/epidemiologia , Eficiência , Qualidade de Vida , Local de Trabalho , Atividades Cotidianas , Adulto , Idoso , Asma/diagnóstico , Asma/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Índice de Gravidade de Doença , Inquéritos e Questionários
19.
Osteoporos Int ; 29(3): 653-663, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29214329

RESUMO

The extent of Canadian provincial variation in hip fracture surgical timing is unclear. Provinces performed a similar proportion of surgeries within three inpatient days after adjustment. Time to surgery varied by timing of admission across provinces. This may reflect different approaches to providing access to hip fracture surgery. INTRODUCTION: The aim of this study was to compare whether time to surgery after hip fracture varies across Canadian provinces for surgically fit patients and their subgroups defined by timing of admission. METHODS: We retrieved hospitalization records for 140,235 patients 65 years and older, treated surgically for hip fracture between 2004 and 2012 in Canada (excluding Quebec). We studied the proportion of surgeries on admission day and within 3 inpatient days, and times required for 33%, 66%, and 90% of surgeries across provinces and by subgroups defined by timing of admission. Differences were adjusted for patient, injury, and care characteristics. RESULTS: Overall, provinces performed similar proportions of surgeries within the recommended three inpatient days, with all provinces requiring one additional day to perform the recommended 90% of surgeries. Prince Edward Island performed 7.0% more surgeries on admission day than Ontario irrespective of timing of admission (difference = 7.0; 95% CI 4.0, 9.9). The proportion of surgeries on admission day was 6.3% lower in Manitoba (difference = - 6.3; 95% CI - 12.1, - 0.6), and 7.7% lower in Saskatchewan (difference = - 7.7; 95% CI - 12.7, - 2.8) compared to Ontario. These differences persisted for late weekday and weekend admissions. The time required for 33%, 66%, and 90% of surgeries ranged from 1 to 2, 2-3, and 3-4 days, respectively, across provinces by timing of admission. CONCLUSIONS: Provinces performed similarly with respect to recommended time for hip fracture surgery. The proportion of surgeries on admission day, and time required to complete 33% and 66% of surgeries, varied across provinces and by timing of admission. This may reflect different provincial approaches to providing access to hip fracture surgery.


Assuntos
Fraturas do Quadril/cirurgia , Admissão do Paciente/estatística & dados numéricos , Tempo para o Tratamento/estatística & dados numéricos , Plantão Médico/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Canadá , Bases de Dados Factuais , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Fatores de Tempo
20.
Mol Cell Proteomics ; 15(10): 3170-3189, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27512079

RESUMO

Cardiomyocytes undergo growth and remodeling in response to specific pathological or physiological conditions. In the former, myocardial growth is a risk factor for cardiac failure and faster protein synthesis is a major factor driving cardiomyocyte growth. Our goal was to quantify the rapid effects of different pro-hypertrophic stimuli on the synthesis of specific proteins in ARVC and to determine whether such effects are caused by alterations on mRNA abundance or the translation of specific mRNAs. Cardiomyocytes have very low rates of protein synthesis, posing a challenging problem in terms of studying changes in the synthesis of specific proteins, which also applies to other nondividing primary cells. To study the rates of accumulation of specific proteins in these cells, we developed an optimized version of the Quantitative Noncanonical Amino acid Tagging LC/MS proteomic method to label and selectively enrich newly synthesized proteins in these primary cells while eliminating the suppressive effects of pre-existing and highly abundant nonisotope-tagged polypeptides. Our data revealed that a classical pathologic (phenylephrine; PE) and the recently identified insulin stimulus that also contributes to the development of pathological cardiac hypertrophy (insulin), both increased the synthesis of proteins involved in, e.g. glycolysis, the Krebs cycle and beta-oxidation, and sarcomeric components. However, insulin increased synthesis of many metabolic enzymes to a greater extent than PE. Using a novel validation method, we confirmed that synthesis of selected candidates is indeed up-regulated by PE and insulin. Synthesis of all proteins studied was up-regulated by signaling through mammalian target of rapamycin complex 1 without changes in their mRNA levels, showing the key importance of translational control in the rapid effects of hypertrophic stimuli. Expression of PKM2 was up-regulated in rat hearts following TAC. This isoform possesses specific regulatory properties, so this finding indicates it may be involved in metabolic remodeling and also serve as a novel candidate biomarker. Levels of translation factor eEF1 also increased during TAC, likely contributing to faster cell mass accumulation. Interestingly those two candidates were not up-regulated in pregnancy or exercise induced CH, indicating PKM2 and eEF1 were pathological CH specific markers. We anticipate that the methodologies described here will be valuable for other researchers studying protein synthesis in primary cells.


Assuntos
Insulina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Fenilefrina/farmacologia , Proteoma/efeitos dos fármacos , Proteômica/métodos , Animais , Células Cultivadas , Cromatografia Líquida , Regulação da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Espectrometria de Massas , Miócitos Cardíacos/metabolismo , Proteoma/genética , Ratos , Ratos Sprague-Dawley
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