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1.
Nat Chem ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030419

RESUMEN

Lys ubiquitination is catalysed by E3 ubiquitin ligases and is central to the regulation of protein stability and cell signalling in normal and disease states. There are gaps in our understanding of E3 mechanisms, and here we use protein semisynthesis, chemical rescue, microscale thermophoresis and other biochemical approaches to dissect the role of catalytic base/acid function and conformational interconversion in HECT-domain E3 catalysis. We demonstrate that there is plasticity in the use of the terminal side chain or backbone carboxylate for proton transfer in HECT E3 ubiquitin ligase reactions, with yeast Rsp5 orthologues appearing to be possible evolutionary intermediates. We also show that the HECT-domain ubiquitin covalent intermediate appears to eject the E2 conjugating enzyme, promoting catalytic turnover. These findings provide key mechanistic insights into how protein ubiquitination occurs and provide a framework for understanding E3 functions and regulation.

2.
Nature ; 626(7997): 194-206, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38096902

RESUMEN

The LINE-1 (L1) retrotransposon is an ancient genetic parasite that has written around one-third of the human genome through a 'copy and paste' mechanism catalysed by its multifunctional enzyme, open reading frame 2 protein (ORF2p)1. ORF2p reverse transcriptase (RT) and endonuclease activities have been implicated in the pathophysiology of cancer2,3, autoimmunity4,5 and ageing6,7, making ORF2p a potential therapeutic target. However, a lack of structural and mechanistic knowledge has hampered efforts to rationally exploit it. We report structures of the human ORF2p 'core' (residues 238-1061, including the RT domain) by X-ray crystallography and cryo-electron microscopy in several conformational states. Our analyses identified two previously undescribed folded domains, extensive contacts to RNA templates and associated adaptations that contribute to unique aspects of the L1 replication cycle. Computed integrative structural models of full-length ORF2p show a dynamic closed-ring conformation that appears to open during retrotransposition. We characterize ORF2p RT inhibition and reveal its underlying structural basis. Imaging and biochemistry show that non-canonical cytosolic ORF2p RT activity can produce RNA:DNA hybrids, activating innate immune signalling through cGAS/STING and resulting in interferon production6-8. In contrast to retroviral RTs, L1 RT is efficiently primed by short RNAs and hairpins, which probably explains cytosolic priming. Other biochemical activities including processivity, DNA-directed polymerization, non-templated base addition and template switching together allow us to propose a revised L1 insertion model. Finally, our evolutionary analysis demonstrates structural conservation between ORF2p and other RNA- and DNA-dependent polymerases. We therefore provide key mechanistic insights into L1 polymerization and insertion, shed light on the evolutionary history of L1 and enable rational drug development targeting L1.


Asunto(s)
Endonucleasas , Elementos de Nucleótido Esparcido Largo , ADN Polimerasa Dirigida por ARN , Transcripción Reversa , Humanos , Microscopía por Crioelectrón , Endonucleasas/química , Endonucleasas/genética , Endonucleasas/metabolismo , Elementos de Nucleótido Esparcido Largo/genética , ARN/genética , ADN Polimerasa Dirigida por ARN/química , ADN Polimerasa Dirigida por ARN/genética , ADN Polimerasa Dirigida por ARN/metabolismo , Cristalografía por Rayos X , ADN/biosíntesis , ADN/genética , Inmunidad Innata , Interferones/biosíntesis
4.
Cancer Discov ; 13(12): 2532-2547, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-37698949

RESUMEN

Improved biomarkers are needed for early cancer detection, risk stratification, treatment selection, and monitoring treatment response. Although proteins can be useful blood-based biomarkers, many have limited sensitivity or specificity for these applications. Long INterspersed Element-1 (LINE-1) open reading frame 1 protein (ORF1p) is a transposable element protein overexpressed in carcinomas and high-risk precursors during carcinogenesis with negligible expression in normal tissues, suggesting ORF1p could be a highly specific cancer biomarker. To explore ORF1p as a blood-based biomarker, we engineered ultrasensitive digital immunoassays that detect mid-attomolar (10-17 mol/L) ORF1p concentrations in plasma across multiple cancers with high specificity. Plasma ORF1p shows promise for early detection of ovarian cancer, improves diagnostic performance in a multianalyte panel, provides early therapeutic response monitoring in gastroesophageal cancers, and is prognostic for overall survival in gastroesophageal and colorectal cancers. Together, these observations nominate ORF1p as a multicancer biomarker with potential utility for disease detection and monitoring. SIGNIFICANCE: The LINE-1 ORF1p transposon protein is pervasively expressed in many cancers and is a highly specific biomarker of multiple common, lethal carcinomas and their high-risk precursors in tissue and blood. Ultrasensitive ORF1p assays from as little as 25 µL plasma are novel, rapid, cost-effective tools in cancer detection and monitoring. See related commentary by Doucet and Cristofari, p. 2502. This article is featured in Selected Articles from This Issue, p. 2489.


Asunto(s)
Carcinoma , Neoplasias Ováricas , Femenino , Humanos , Elementos de Nucleótido Esparcido Largo , Proteínas/genética , Biomarcadores de Tumor , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética
5.
bioRxiv ; 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36747644

RESUMEN

Improved biomarkers are needed for early cancer detection, risk stratification, treatment selection, and monitoring treatment response. While proteins can be useful blood-based biomarkers, many have limited sensitivity or specificity for these applications. Long INterspersed Element-1 (LINE-1, L1) open reading frame 1 protein (ORF1p) is a transposable element protein overexpressed in carcinomas and high-risk precursors during carcinogenesis with negligible detectable expression in corresponding normal tissues, suggesting ORF1p could be a highly specific cancer biomarker. To explore the potential of ORF1p as a blood-based biomarker, we engineered ultrasensitive digital immunoassays that detect mid-attomolar (10-17 M) ORF1p concentrations in patient plasma samples across multiple cancers with high specificity. Plasma ORF1p shows promise for early detection of ovarian cancer, improves diagnostic performance in a multi-analyte panel, and provides early therapeutic response monitoring in gastric and esophageal cancers. Together, these observations nominate ORF1p as a multi-cancer biomarker with potential utility for disease detection and monitoring.

6.
J ISAKOS ; 8(4): 246-254, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36646169

RESUMEN

OBJECTIVES: Results from the Stability Study suggest that adding a lateral extra-articular tenodesis (LET) to a hamstring tendon autograft reduces the rate of anterior cruciate ligament reconstruction (ACLR) failure in high-risk patients. The purpose of this study is to report adverse events over the 2-year follow-up period and compare groups (ACLR alone vs. ACLR + LET). METHODS: Stability is a randomized clinical trial comparing hamstring tendon ACLR with and without LET. Patients aged 14-25 years with an ACL deficient knee were included. Patients were followed and adverse events documented (type, actions taken, resolution) with visits at 3, 6, 12, and 24 months postoperatively. Adverse events were categorized as none, minor medical, minor surgical, contralateral ACL rupture, or graft rupture. Patient reported outcome measures (PROMs) collected at each visit included the Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee Score (IKDC), and ACL Quality of Life Questionnaire (ACL-QOL). RESULTS: In total, 618 patients were randomized (mean age 18.9 years, 302 (49%) male). Forty-five patients (7%) suffered graft rupture; 34 (11%) in the ACLR group compared to 11 (4%) in the ACLR + LET group (RRR = 0.67, 95% CI 0.36 to 0.83, p < 0.001). There were no differences in effusion or infection rates between groups. The ACLR + LET group experienced an increased number of hardware removals (10 vs. 4). Overall, the rate of minor medical events (11%), minor surgical events (7%), and ipsilateral or contralateral ACL tears (10%) were low considering the high-risk patient profile. Increasing severity of adverse events was associated with lower PROMs at 24 months post-operative. Patients in the ACLR + LET group reported greater degree of pain at 3 months only. There were no clinically significant differences in range of motion between groups. CONCLUSIONS: The addition of LET to hamstring tendon autograft ACLR in young patients at high risk of re-injury resulted in a statistically significant reduction in graft rupture. While the addition of LET may increase rates of hardware irritation, there was no significant increase in overall rates of minor medical adverse events, minor surgical events, or overall re-operation rates. The concerns regarding complications associated with a LET did not materialize in this study. LEVEL OF EVIDENCE: Level I.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Tenodesis , Humanos , Masculino , Adolescente , Femenino , Tenodesis/efectos adversos , Tenodesis/métodos , Calidad de Vida , Reconstrucción del Ligamento Cruzado Anterior/métodos , Articulación de la Rodilla/cirugía , Lesiones del Ligamento Cruzado Anterior/cirugía
7.
J Dairy Sci ; 106(1): 653-663, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36400618

RESUMEN

Dairy cows are predisposed to diseases during the postpartum period. Dystocia has been associated with increased risk for disease, which is likely the result of increased tissue trauma and stress during the prolonged parturition. To attenuate the inflammatory response seen in dystocic animals and improve well-being, we assessed the effects of a glucocorticoid, dexamethasone administered within 12 h after calving. Dystocia was defined as a difficult birth resulting in a prolonged calving (≥70 min after the amniotic sac appears) and was monitored through 3 video cameras in the close-up dry-cow pen. Cows meeting the dystocia definition were randomly assigned to receive a single intramuscular injection of either dexamethasone (DEX; 0.1 mg/kg of body weight; n = 43) or saline (CON, n = 44) within 12 h following a dystocic calving. Serum haptoglobin, blood ß-hydroxybutyrate (BHB) concentrations, body temperature, and several behaviors were measured for the first 7 d postpartum. Additionally, milk production and components for the first 120 d were recorded. Using a mixed model, the fixed effects of treatment, parity, calving assistance, and time, along with 2- and 3-way interactions, were analyzed with cow as a random effect. We observed that primiparous DEX cows had greater serum haptoglobin concentrations on d 3 and d 7 postpartum compared with primiparous CON cows. There was no difference between treatment groups for blood BHB concentrations and body temperature. Behavior was altered between treatments, with DEX cows having reduced activity for the first week postpartum, as well as less restlessness and increased lying times on some of the days following calving. Treatment interacted with time for milk yield, such that DEX cows produced 2.7 kg/d less milk than CON cows for the first month following calving. The administration of dexamethasone resulted in changes in behavioral measurements, which could suggest a reduction in discomfort; however, due to the reduction in milk yield for the first month following calving, DEX administration may not be applicable for typical farm use. Additional research is needed to investigate treatments for cows experiencing dystocia without detrimental effects on milk yield.


Asunto(s)
Enfermedades de los Bovinos , Distocia , Embarazo , Femenino , Bovinos , Animales , Lactancia/fisiología , Haptoglobinas , Leche , Periodo Posparto , Paridad , Ácido 3-Hidroxibutírico , Distocia/tratamiento farmacológico , Distocia/veterinaria , Dexametasona/farmacología , Enfermedades de los Bovinos/tratamiento farmacológico
8.
J Geod ; 95(7): 80, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720451

RESUMEN

Satellite altimetry and gravimetry are used to determine the mean seasonal cycle in relative sea level, a quantity relevant to coastal flooding and related applications. The main harmonics (annual, semiannual, terannual) are estimated from 25 years of gridded altimetry, while several conventional altimeter "corrections" (gravitational tide, pole tide, and inverted barometer) are restored. To transform from absolute to relative sea levels, a model of vertical land motion is developed from a high-resolution seasonal mass inversion estimated from satellite gravimetry. An adjustment for annual geocenter motion accounts for use of a center-of-mass reference frame in satellite orbit determination. A set of 544 test tide gauges, from which seasonal harmonics have been estimated from hourly measurements, is used to assess how accurately each adjustment to the altimeter data helps converge the results to true relative sea levels. At these gauges, the median annual and semiannual amplitudes are 7.1 cm and 2.2 cm, respectively. The root-mean-square differences with altimetry are 3.24 and 1.17 cm, respectively, which are reduced to 1.93 and 0.86 cm after restoration of corrections and adjustment for land motion. Example outliers highlight some limitations of present-day coastal altimetry owing to inadequate spatial resolution: upwelling and currents off Oregon and wave setup at Minamitori Island.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36168484

RESUMEN

Background: The pandemic caused by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) has dramatically increased cheshospitalizations, and it is often difficult to determine whether there is a bacterial or fungal coinfection at time of presentation. In this study, we sought to determine the rates of coinfection and utilization of antibiotics in SARS-CoV-2 disease. Methods: Retrospective chart review of patients hospitalized with COVID-19 pneumonia from April 13, 2020, to July 14, 2020. Results: In total, 277 patients were hospitalized for COVID-19 pneumonia during this period. Patients that received antibiotics within 48 hours of presentation were more likely to be febrile (59.3% vs 41.2%; P = .01) and to have leukocytosis (23.9% vs 5.9%; P < .01) and were less likely to have a procalcitonin level <0.25 ng/mL (58.8% vs 74.5%; P = .04). In total, 45 patients had positive blood cultures collected during hospitalization, 16 of which were clinically significant. Of the clinically significant blood cultures, 5 were collected <48 hours of admission. Moreover, 18 sputum cultures were clinically significant, 2 of which were collected within 48 hours of admission. Conclusion: Bacterial and fungal coinfections in COVID-19 appear to be rare on presentation; thus, this factor may be a good target for enhanced antibiotic stewardship.

10.
Artículo en Inglés | MEDLINE | ID: mdl-31807496

RESUMEN

Changes in terrestrial water storage (TWS) in High Mountain Asia (HMA) could have major societal impacts, as the region's large reservoirs of glaciers, snow, and groundwater provide a freshwater source to more than one billion people. We seek to quantify and close the budget of secular changes in TWS over the span of the GRACE satellite mission (2003-2016). To assess the TWS trend budget we consider a new high-resolution mass trend product determined directly from GRACE L1B data, glacier mass balance derived from Digital Elevation Models (DEMs), groundwater variability determined from confined and unconfined well observations, and terrestrial water budget estimates from a suite of land surface model simulations with the NASA Land Information System (LIS). This effort is successful at closing the aggregated TWS trend budget over the entire HMA region, the glaciated portion of HMA, and the Indus and Ganges basins, where the full-region trends are primarily due to the glacier mass balance and groundwater signals. Additionally, we investigate the closure of TWS trends at individual 1-arc-degree mascons (area ≈12,000 km2); a significant improvement in spatial resolution over previous analyses of GRACE-derived trends. This mascon-level analysis reveals locations where the TWS trends are well-explained by the independent datasets, as well as regions where they are not; identifying specific geographic areas where additional data and model improvements are needed. The accurate characterization of total TWS trends and its components presented here is critical to understanding the complex dynamics of the region, and is a necessary step toward projecting future water mass changes in HMA.

11.
J Dent Res ; 98(6): 659-665, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30917284

RESUMEN

This study investigated the genetic basis of an unusual autosomal dominant phenotype characterized by familial absent uvula, with a short posterior border of the soft palate, abnormal tonsillar pillars, and velopharyngeal insufficiency. Cytogenetic analysis and single-nucleotide polymorphism-based linkage analysis were investigated in a 4-generation family with 8 affected individuals. Whole exome sequencing data were overlaid, and segregation analysis identified a single missense variant, p.Q433P in the FOXF2 transcription factor, that fully segregated with the phenotype. This was found to be in linkage disequilibrium with a small 6p25.3 tandem duplication affecting FOXC1 and GMDS. Notably, the copy number imbalances of this region are commonly associated with pathologies that are not present in this family. Bioinformatic predictions with luciferase reporter studies of the FOXF2 missense variant indicated a negative impact, affecting both protein stability and transcriptional activation. Foxf 2 is expressed in the posterior mouse palate, and knockout animals develop an overt cleft palate. Since mice naturally lack the structural equivalent of the uvula, we demonstrated FOXF2 expression in the developing human uvula. Decipher also records 2 individuals with hypoplastic or bifid uvulae with copy number variants affecting FOXF2. Nevertheless, given cosegregation with the 6p25.3 duplications, we cannot rule out a combined effect of these gains and the missense variant on FOXF2 function, which may account for the rare palate phenotype observed.


Asunto(s)
Factores de Transcripción Forkhead/genética , Paladar Blando/patología , Úvula/patología , Preescolar , Análisis Mutacional de ADN , Egipto , Femenino , Humanos , Desequilibrio de Ligamiento , Masculino , Tonsila Palatina/patología , Linaje , Polimorfismo de Nucleótido Simple
12.
J Virol ; 93(4)2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30487274

RESUMEN

Vesicular stomatitis virus (VSV) (a rhabdovirus) and its variant VSV-ΔM51 are widely used model systems to study mechanisms of virus-host interactions. Here, we investigated how the cell cycle affects replication of these viruses using an array of cell lines with different levels of impairment of antiviral signaling and a panel of chemical compounds arresting the cell cycle at different phases. We observed that all compounds inducing cell cycle arrest in G2/M phase strongly enhanced the replication of VSV-ΔM51 in cells with functional antiviral signaling. G2/M arrest strongly inhibited type I and type III interferon (IFN) production as well as expression of IFN-stimulated genes in response to exogenously added IFN. Moreover, G2/M arrest enhanced the replication of Sendai virus (a paramyxovirus), which is also highly sensitive to the type I IFN response but did not stimulate the replication of a wild-type VSV that is more effective at evading antiviral responses. In contrast, the positive effect of G2/M arrest on virus replication was not observed in cells defective in IFN signaling. Altogether, our data show that replication of IFN-sensitive cytoplasmic viruses can be strongly stimulated during G2/M phase as a result of inhibition of antiviral gene expression, likely due to mitotic inhibition of transcription, a global repression of cellular transcription during G2/M phase. The G2/M phase thus could represent an "Achilles' heel" of the infected cell, a phase when the cell is inadequately protected. This model could explain at least one of the reasons why many viruses have been shown to induce G2/M arrest.IMPORTANCE Vesicular stomatitis virus (VSV) (a rhabdovirus) and its variant VSV-ΔM51 are widely used model systems to study mechanisms of virus-host interactions. Here, we investigated how the cell cycle affects replication of VSV and VSV-ΔM51. We show that G2/M cell cycle arrest strongly enhances the replication of VSV-ΔM51 (but not of wild-type VSV) and Sendai virus (a paramyxovirus) via inhibition of antiviral gene expression, likely due to mitotic inhibition of transcription, a global repression of cellular transcription during G2/M phase. Our data suggest that the G2/M phase could represent an "Achilles' heel" of the infected cell, a phase when the cell is inadequately protected. This model could explain at least one of the reasons why many viruses have been shown to induce G2/M arrest, and it has important implications for oncolytic virotherapy, suggesting that frequent cell cycle progression in cancer cells could make them more permissive to viruses.


Asunto(s)
Puntos de Control del Ciclo Celular/fisiología , Vesiculovirus/genética , Replicación Viral/genética , Animales , Antivirales/farmacología , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Citoplasma , Fase G2/fisiología , Puntos de Control de la Fase G2 del Ciclo Celular/fisiología , Expresión Génica/genética , Humanos , Interferón Tipo I/metabolismo , Interferón gamma/metabolismo , Interferones , Puntos de Control de la Fase M del Ciclo Celular/fisiología , Viroterapia Oncolítica/métodos , Virus Oncolíticos/genética , Virus ARN/inmunología , Virus ARN/metabolismo , Virus Sendai/genética , Virus Sendai/metabolismo , Transducción de Señal , Virus de la Estomatitis Vesicular Indiana/genética , Vesiculovirus/metabolismo , Proteínas de la Matriz Viral/genética , Replicación Viral/inmunología , Interferón lambda
13.
Osteoarthritis Cartilage ; 27(4): 580-585, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30590193

RESUMEN

OBJECTIVES: Despite the recognized importance of neuromuscular exercises, there is currently no widely accepted clinical outcome measure focused on neuromuscular control for patients with knee osteoarthritis (OA). The purposes of the present study were to investigate the test-retest reliability, concurrent validity and longitudinal validity of the star excursion balance test (SEBT) in patients with knee OA. DESIGN: 74 patients performed the SEBT on two sessions within 7 days, and on a third session after completing 12 weeks of a home exercise program focused on neuromuscular control. A subgroup of 37 performed the SEBT while in the field of view of a motion capture system to estimate concurrent validity. The SEBT was recorded in cm and also normalized to leg length (LL). Participants also completed the 40 m fast-paced walk test and patient-reported outcomes before and after the exercise program. RESULTS: Intraclass correlation coefficients (95% confidence intervals) were 0.94 (0.91 to 0.96) and 0.93 (0.89 to 0.96) and standard errors of measurement were ±2.68 cm and ±3.05%LL for raw and normalized composite scores, respectively. The minimum detectable change at the 95% confidence level for the composite score was 7.44 cm and 8.45%LL. Correlations between observer and motion capture measures were very high (Pearson r > 0.96). There was a significant increase in SEBT following the exercise program (standardized response mean = 0.74). The change in SEBT had low correlations with changes in 40 m walk times (r = 0.26) and pain (r = 0.28). CONCLUSION: The SEBT has suitable measurement properties for use in patients with knee OA.


Asunto(s)
Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Imagenología Tridimensional/métodos , Músculo Esquelético/fisiopatología , Osteoartritis de la Rodilla/rehabilitación , Equilibrio Postural/fisiología , Fenómenos Biomecánicos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/fisiopatología , Evaluación de Resultado en la Atención de Salud , Reproducibilidad de los Resultados
14.
Anesth Analg ; 127(5): 1118-1126, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29533264

RESUMEN

BACKGROUND: Globally, >300 million patients have surgery annually, and ≤20% experience adverse postoperative events. We studied the impact of both cardiac and noncardiac adverse events on 1-year disability-free survival after noncardiac surgery. METHODS: We used the study cohort from the Evaluation of Nitrous oxide in Gas Mixture of Anesthesia (ENIGMA-II) trial, an international randomized trial of 6992 noncardiac surgical patients. All were ≥45 years of age and had moderate to high cardiac risk. The primary outcome was mortality within 1 postoperative year. We defined 4 separate types of postoperative adverse events. Major adverse cardiac events (MACEs) included myocardial infarction (MI), cardiac arrest, and myocardial revascularization with or without troponin elevation. MI was defined using the third Universal Definition and was blindly adjudicated. A second cohort consisted of patients with isolated troponin increases who did not meet the definition for MI. We also considered a cohort of patients who experienced major adverse postoperative events (MAPEs), including unplanned admission to intensive care, prolonged mechanical ventilation, wound infection, pulmonary embolism, and stroke. From this cohort, we identified a group without troponin elevation and another with troponin elevation that was not judged to be an MI. Multivariable Cox proportional hazard models for death at 1 year and assessments of proportionality of hazard functions were performed and expressed as an adjusted hazard ratio (aHR) and 95% confidence intervals (CIs). RESULTS: MACEs were observed in 469 patients, and another 754 patients had isolated troponin increases. MAPEs were observed in 631 patients. Compared with control patients, patients with a MACE were at increased risk of mortality (aHR, 3.36 [95% CI, 2.55-4.46]), similar to patients who suffered a MAPE without troponin elevation (n = 501) (aHR, 2.98 [95% CI, 2.26-3.92]). Patients who suffered a MAPE with troponin elevation but without MI had the highest risk of death (n = 116) (aHR, 4.29 [95% CI, 2.89-6.36]). These 4 types of adverse events similarly affected 1-year disability-free survival. CONCLUSIONS: MACEs and MAPEs occur at similar frequencies and affect survival to a similar degree. All 3 types of postoperative troponin elevation in this analysis were associated, to varying degrees, with increased risk of death and disability.


Asunto(s)
Anestésicos por Inhalación/efectos adversos , Cardiopatías/epidemiología , Óxido Nitroso/efectos adversos , Procedimientos Quirúrgicos Operativos/efectos adversos , Administración por Inhalación , Anciano , Anestésicos por Inhalación/administración & dosificación , Biomarcadores/sangre , Evaluación de la Discapacidad , Femenino , Estado de Salud , Cardiopatías/diagnóstico , Cardiopatías/mortalidad , Cardiopatías/terapia , Humanos , Masculino , Persona de Mediana Edad , Óxido Nitroso/administración & dosificación , Medición de Riesgo , Factores de Riesgo , Procedimientos Quirúrgicos Operativos/mortalidad , Factores de Tiempo , Resultado del Tratamiento , Troponina/sangre , Regulación hacia Arriba
15.
Osteoporos Int ; 29(2): 265-286, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29306984

RESUMEN

Osteoporosis affects many aspects of daily life. The aim of this systematic review was to assess the effects of exercise interventions on functional outcomes in persons with osteoporosis, in comparison with controls. METHODS: Four databases were searched and yielded 1587 citations. Two reviewers independently determined study eligibility, rated risk of bias, appraised methodological quality of studies, and resolved discordance by consensus. RESULTS: A total of 28 studies examining 2113 participants met inclusion criteria; 25 studies were suitable for meta-analyses. Four categories of exercise were identified using the ProFaNE taxonomy. After removing studies with high risk of bias and sorting them into intervention sub-types, we were able to sufficiently reduce the heterogeneity. The standardized mean difference (SMD) favored multicomponent exercise for mobility (- 0.56, 95% CI [- 0.81, - 0.32], p = 0.06, I2 = 51%); balance (0.50, 95% CI [0.27, 0.74], p = 0.28, I2 = 21%); and self-reported measures of functioning (- 0.69, 95% CI [- 1.04, - 0.34], p = 0.02, I2 = 61%). Trials were judged at low or unclear risk of selection bias, indicating inadequate reporting and at high risk of performance bias due to lack of participant blinding. The mean methodological quality rating of the studies was 63.5% indicating moderate quality. CONCLUSIONS: A multicomponent exercise program of high-speed training combined with simulated functional tasks is promising to enhance functional outcomes. Due to substantial clinical heterogeneity of the target groups and specific demands of exercise modes, it is unclear which exercise program is optimal.


Asunto(s)
Terapia por Ejercicio/métodos , Osteoporosis/rehabilitación , Sesgo , Prueba de Esfuerzo/métodos , Humanos , Osteoporosis/fisiopatología , Recuperación de la Función , Resultado del Tratamiento
16.
Osteoarthritis Cartilage ; 25(12): 1999-2006, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28888904

RESUMEN

OBJECTIVE: To evaluate 5-year outcomes after lower limb realignment and test the hypothesis that surgery-induced changes in selected biomechanical risk factors for medial knee osteoarthritis (OA) are associated with clinically important improvements. DESIGN: We prospectively evaluated patient-reported outcomes, full-limb standing radiographs and gait biomechanics before, 6 months (surgery-induced change) and 5 years after medial opening wedge high tibial osteotomy (HTO) in 170 patients (46.4 ± 8.9 years, 135 males) with knee OA and varus alignment. Logistic regression tested the associations of 6-month changes in mechanical axis angle and knee adduction moment with achieving an increase of ≥10 points in the Knee injury and Osteoarthritis Outcome Score (KOOS)4 at 5 years, with and without adjusting for covariates. Gait data were also compared to existing data from healthy controls. RESULTS: Mean 5-year changes (95% confidence interval (CI)) were: KOOS4: +14.2 (10.8, 17.6); mechanical axis angle: +8.21° (7.58, 8.83); knee adduction moment: -1.49 %BW*Ht (-1.35, -1.63). The postoperative knee adduction moments were typically lower than values for healthy controls. When divided into quartiles, although all strata improved significantly, patients with reductions in knee adduction moment of 1.14-1.74 %BW*Ht (neither largest nor smallest changes) had highest 5-year KOOS4 scores. The 6-month change in knee adduction moment (odds ratios (OR) = 0.38; 95% CI: 0.22, 0.67), preoperative KOOS4 (OR = 0.96; 95% CI: 0.94, 0.99) and preoperative medial tibiofemoral narrowing grade (OR = 0.62; 95% CI: 0.37, 1.00) were negatively associated with having a 5-year clinically important improvement (C-statistic = 0.70). CONCLUSIONS: Substantial improvements in biomechanical risk factors and patient-reported outcomes are observed 5 years after medial opening wedge HTO. The surgery-induced change in load distribution during walking is significantly associated with long-term clinically important improvement.


Asunto(s)
Desviación Ósea/cirugía , Marcha/fisiología , Genu Varum/cirugía , Osteoartritis de la Rodilla/cirugía , Osteotomía/métodos , Tibia/cirugía , Adulto , Fenómenos Biomecánicos , Desviación Ósea/complicaciones , Desviación Ósea/diagnóstico por imagen , Desviación Ósea/fisiopatología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Genu Varum/complicaciones , Genu Varum/diagnóstico por imagen , Genu Varum/fisiopatología , Humanos , Modelos Logísticos , Extremidad Inferior/diagnóstico por imagen , Extremidad Inferior/fisiopatología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/fisiopatología , Medición de Resultados Informados por el Paciente , Estudios Prospectivos , Radiografía , Factores de Riesgo , Resultado del Tratamiento
17.
J Clin Anesth ; 27(8): 672-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26371714

RESUMEN

STUDY OBJECTIVE: To assess whether the use of intraoperative opioids is associated with poor recurrence-free survival (RFS) and overall survival (OS) after lung cancer surgery. DESIGN: Retrospective study. SETTING: Academic hospital. SUBJECTS: Patients with laryngeal primary or recurrent laryngeal squamous cell carcinoma who had surgery. INTERVENTIONS: Intravenous opioids (remifentanil, fentanyl, sufentanil, and hydromorphone). MEASUREMENTS: Univariate and multicovariate Cox proportional hazards models were applied to assess the effects of covariates of interest on OS and RFS. MAIN RESULTS: A total of 195 patients were included. All received opioids intraoperatively. The multivariate analysis demonstrated that age (hazard ratio [HR], 1.03; P = .005), negative margin status (HR, 0.163; P = .001], postoperative chemotherapy (HR, 7.38; P < .001), and concurrent chemotherapy and radiation (HR, 3.11; P < .001) treatment and fentanyl equivalent use (HR, 1.001; P = .02) were all predictor factors for 3- and 5-year RFS. The same variables were predictor factors for OS (age: HR, 1.03 [P = .003]; negative margin status: HR, 0.14 [P = .001]; postoperative chemotherapy: HR, 4 [P < .0001]; and fentanyl equivalent use: HR, 1.001 [P = .02]). CONCLUSIONS: Our study demonstrates a very weak association between the use of intraoperative opioids and cancer recurrence after laryngeal squamous cell carcinoma surgery.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias Laríngeas/cirugía , Administración Intravenosa , Anciano , Analgésicos Opioides/efectos adversos , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Cuidados Intraoperatorios , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Tasa de Supervivencia
18.
Osteoarthritis Cartilage ; 23(2): 178-88, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25447975

RESUMEN

To review and synthesize the biomechanical effects of valgus knee bracing for patients with medial knee osteoarthritis (OA). Electronic databases were searched from their inception to May 2014. Two reviewers independently determined study eligibility, rated study quality and extracted data. Where possible, data were combined into meta-analyses and pooled estimates with 95% confidence intervals (CI) for standardized mean differences (SMD) were calculated. Thirty studies were included with 478 subjects tested while using a valgus knee brace. Various biomechanical methods suggested valgus braces can decrease direct measures of medial knee compressive force, indirect measures representing the mediolateral distribution of load across the knee, quadriceps/hamstring and quadriceps/gastrocnemius co-contraction ratios, and increase medial joint space during gait. Meta-analysis from 17 studies suggested a statistically significant decrease in the external knee adduction moment (KAM) during walking, with a moderate-to-high effect size (SMD = 0.61; 95% CI: 0.39, 0.83; P < 0.001). Meta-regression identified a near-significant association for the KAM effect size and duration of brace use only (ß, -0.01; 95% CI: -0.03, 0.0001; P = 0.06); with longer durations of brace use associated with smaller treatment effects. Minor complications were commonly reported during brace use and included slipping, discomfort and poor fit, blisters and skin irritation. Systematic review and meta-analysis suggests valgus knee braces can alter knee joint loads through a combination of mechanisms, with moderate-to-high effect sizes in biomechanical outcomes.


Asunto(s)
Desviación Ósea/fisiopatología , Desviación Ósea/terapia , Tirantes , Articulación de la Rodilla/fisiopatología , Fenómenos Biomecánicos , Humanos
19.
Geobiology ; 12(5): 451-68, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24976102

RESUMEN

Mahoney Lake represents an extreme meromictic model system and is a valuable site for examining the organisms and processes that sustain photic zone euxinia (PZE). A single population of purple sulfur bacteria (PSB) living in a dense phototrophic plate in the chemocline is responsible for most of the primary production in Mahoney Lake. Here, we present metagenomic data from this phototrophic plate--including the genome of the major PSB, as obtained from both a highly enriched culture and from the metagenomic data--as well as evidence for multiple other taxa that contribute to the oxidative sulfur cycle and to sulfate reduction. The planktonic PSB is a member of the Chromatiaceae, here renamed Thiohalocapsa sp. strain ML1. It produces the carotenoid okenone, yet its closest relatives are benthic PSB isolates, a finding that may complicate the use of okenone (okenane) as a biomarker for ancient PZE. Favorable thermodynamics for non-phototrophic sulfide oxidation and sulfate reduction reactions also occur in the plate, and a suite of organisms capable of oxidizing and reducing sulfur is apparent in the metagenome. Fluctuating supplies of both reduced carbon and reduced sulfur to the chemocline may partly account for the diversity of both autotrophic and heterotrophic species. Collectively, the data demonstrate the physiological potential for maintaining complex sulfur and carbon cycles in an anoxic water column, driven by the input of exogenous organic matter. This is consistent with suggestions that high levels of oxygenic primary production maintain episodes of PZE in Earth's history and that such communities should support a diversity of sulfur cycle reactions.


Asunto(s)
Chromatiaceae/genética , Chromatiaceae/metabolismo , Lagos/microbiología , Azufre/metabolismo , Colombia Británica , Genoma Bacteriano , Datos de Secuencia Molecular , Oxidación-Reducción , Filogeografía , Análisis de Secuencia de ADN
20.
Geophys Res Lett ; 41(10): 3382-3389, 2014 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-26074638

RESUMEN

We have derived a gravity field solution in spherical harmonics to degree and order 900, GRGM900C, from the tracking data of the Gravity Recovery and Interior Laboratory (GRAIL) Primary (1 March to 29 May 2012) and Extended Missions (30 August to 14 December 2012). A power law constraint of 3.6 ×10-4/ℓ2 was applied only for degree ℓ greater than 600. The model produces global correlations of gravity, and gravity predicted from lunar topography of ≥ 0.98 through degree 638. The model's degree strength varies from a minimum of 575-675 over the central nearside and farside to 900 over the polar regions. The model fits the Extended Mission Ka-Band Range Rate data through 17 November 2012 at 0.13 µm/s RMS, whereas the last month of Ka-Band Range-Rate data obtained from altitudes of 2-10 km fit at 0.98 µm/s RMS, indicating that there is still signal inherent in the tracking data beyond degree 900.

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