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1.
J Phys Chem Lett ; : 8187-8195, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093598

RESUMEN

Gas-phase potential energy surfaces (PESs) are often used to provide an intuitive understanding of molecular chemical reactivity. Most chemical reactions, however, take place in solution, and it is unclear whether gas-phase PESs accurately represent chemical processes in solvent environments. In this work we use quantum simulations to investigate the dissociation energetics of NaK+ in liquid tetrahydrofuran (THF) to understand the degree to which solvent interactions alter the gas-phase picture. Using umbrella sampling and thermodynamic integration techniques, we construct condensed-phase free energy surfaces of NaK+ on THF in both the ground and electronic excited states. We find that solvation by THF completely alters the nature of the NaK+ bond by reordering the thermodynamic dissociation products. Reaching the thermodynamic dissociation limit in THF also requires a long-range charge transfer process that has no counterpart in the gas phase. Gas-phase PESs, even with perturbations, cannot adequately describe the reactivity of simple asymmetric molecules in solution.

2.
N Engl J Med ; 391(6): 526-537, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115062

RESUMEN

BACKGROUND: In early-onset severe hemolytic disease of the fetus and newborn (HDFN), transplacental transfer of maternal antierythrocyte IgG alloantibodies causes fetal anemia that leads to the use of high-risk intrauterine transfusions in order to avoid fetal hydrops and fetal death. Nipocalimab, an anti-neonatal Fc receptor blocker, inhibits transplacental IgG transfer and lowers maternal IgG levels. METHODS: In an international, open-label, single-group, phase 2 study, we assessed treatment with intravenous nipocalimab (30 or 45 mg per kilogram of body weight per week) administered from 14 to 35 weeks' gestation in participants with pregnancies at high risk for recurrent early-onset severe HDFN. The primary end point was live birth at 32 weeks' gestation or later without intrauterine transfusions as assessed against a historical benchmark (0%; clinically meaningful difference, 10%). RESULTS: Live birth at 32 weeks' gestation or later without intrauterine transfusions occurred in 7 of 13 pregnancies (54%; 95% confidence interval, 25 to 81) in the study. No cases of fetal hydrops occurred, and 6 participants (46%) did not receive any antenatal or neonatal transfusions. Six fetuses received an intrauterine transfusion: five fetuses at 24 weeks' gestation or later and one fetus before fetal loss at 22 weeks and 5 days' gestation. Live birth occurred in 12 pregnancies. The median gestational age at delivery was 36 weeks and 4 days. Of the 12 live-born infants, 1 received one exchange transfusion and one simple transfusion and 5 received only simple transfusions. Treatment-related decreases in the alloantibody titer and IgG level were observed in maternal samples and cord blood. No unusual maternal or pediatric infections were observed. Serious adverse events were consistent with HDFN, pregnancy, or prematurity. CONCLUSIONS: Nipocalimab treatment delayed or prevented fetal anemia or intrauterine transfusions, as compared with the historical benchmark, in pregnancies at high risk for early-onset severe HDFN. (Funded by Janssen Research and Development; UNITY ClinicalTrials.gov number, NCT03842189.).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Transfusión de Sangre Intrauterina , Eritroblastosis Fetal , Inmunoglobulina G , Humanos , Femenino , Embarazo , Recién Nacido , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Adulto , Inmunoglobulina G/sangre , Transfusión de Sangre Intrauterina/efectos adversos , Nacimiento Vivo , Isoanticuerpos/sangre , Receptores Fc , Edad Gestacional , Antígenos de Histocompatibilidad Clase I
3.
Am J Epidemiol ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39108175

RESUMEN

Studying the effect of duration of treatment on prognostic outcomes using real-world data is challenging because only people who survive for a long time can receive a treatment for a long time. Specifying a target trial helps overcome such challenge. We aimed to estimate the effect of different durations of treatment with antihypertensive drugs with anticholinergic properties (AC AHT) on the risk of vascular dementia and Alzheimer's disease by emulating a target trial using the UK CPRD GOLD database (2001-2017). Comparing treatment for 3-6 years versus ≤3 years yielded null results for both types of dementia. Comparing a longer duration of treatment, >6 years versus ≤3 years, yielded a 10-year risk ratio of 0.69 (95% CI, 0.54-0.90) for vascular dementia and 0.91 (95% CI, 0.77-1.10) for Alzheimer's disease. For illustration, we performed an analysis that failed to emulate a target trial by assigning exposure categories using post-baseline information, obtaining implausible beneficial estimates. Our findings indicate a modest benefit of longer duration of treatment with AC AHT on vascular dementia and highlight the value of the target trial emulation to avoid selection bias in the evaluation of the effect of different durations of treatment.

4.
Alzheimers Dement (Amst) ; 16(3): e12623, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39130802

RESUMEN

INTRODUCTION: Whether circulating levels of sphingolipids are prospectively associated with cognitive decline and dementia risk is uncertain. METHODS: We measured 14 sphingolipid species in plasma samples from 4488 participants (mean age 76.2 years; 40% male; and 25% apolipoprotein E (APOE) ε4 allele carriers). Cognitive decline was assessed annually across 6 years using modified Mini-Mental State Examination (3MSE) and Digital Symbol Substitution Test (DSST). Additionally, a subset of 3050 participants were followed for clinically adjudicated dementia. RESULTS: Higher plasma levels of sphingomyelin-d18:1/16:0 (SM-16) were associated with a faster cognitive decline measured with 3MSE, in contrast, higher levels of sphingomyelin-d18:1/22:0 (SM-22) were associated with slower decline in cognition measured with DSST. In Cox regression, higher levels of SM-16 (hazard ration [HR] = 1.24 [95% confidence interval [CI]: 1.08-1.44]) and ceramide-d18:1/16:0 (Cer-16) (HR = 1.26 [95% CI: 1.10-1.45]) were associated with higher risk of incident dementia. DISCUSSION: Several sphingolipid species appear to be involved in cognitive decline and dementia risk. Highlights: Plasma levels of sphingolipids were associated with cognitive decline and dementia risk.Ceramides and sphingomyelins with palmitic acid were associated with faster annual cognitive decline and increased risk of dementia.The direction of association depended on the covalently bound saturated fatty acid chain length in analysis of cognitive decline.

5.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39125622

RESUMEN

Bacteria are known to be constantly adapting to become resistant to antibiotics. Currently, efficient antibacterial compounds are still available; however, it is only a matter of time until these compounds also become inefficient. Ribonucleases are the enzymes responsible for the maturation and degradation of RNA molecules, and many of them are essential for microbial survival. Members of the PNPase and RNase II families of exoribonucleases have been implicated in virulence in many pathogens and, as such, are valid targets for the development of new antibacterials. In this paper, we describe the use of virtual high-throughput screening (vHTS) to identify chemical compounds predicted to bind to the active sites within the known structures of RNase II and PNPase from Escherichia coli. The subsequent in vitro screening identified compounds that inhibited the activity of these exoribonucleases, with some also affecting cell viability, thereby providing proof of principle for utilizing the known structures of these enzymes in the pursuit of new antibacterials.


Asunto(s)
Antibacterianos , Inhibidores Enzimáticos , Escherichia coli , Exorribonucleasas , Antibacterianos/farmacología , Antibacterianos/química , Exorribonucleasas/antagonistas & inhibidores , Exorribonucleasas/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Dominio Catalítico , Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/antagonistas & inhibidores , Bacterias/efectos de los fármacos , Bacterias/enzimología
6.
Clin J Sport Med ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39133106

RESUMEN

OBJECTIVE: To investigate the effects of reduced weight running on the antigravity (AG) treadmill on maintenance of normal muscle activation and reduction of plantar forces in healthy subjects. DESIGN: Descriptive laboratory study. SETTING: Clinical sports medicine center. PARTICIPANTS: Twenty healthy subjects (10 male and 10 female) aged 18 to 29 years. INDEPENDENT VARIABLES: Subjects running at 6.5 miles per hour on a standard treadmill and on the AG treadmill at 100%, 90%, 80%, 70%, 60%, and 50% of bodyweight levels. MAIN OUTCOME MEASURES: Dynamic plantar loading data were recorded using pressure insoles. Surface electromyography electrodes with imbedded accelerometers were used to estimate timing and magnitude of muscle activity, stride length, and cadence. RESULTS: There was a significant, sequential reduction in peak pressure, maximum force, and force time integral (FTI) with decreasing bodyweight. A 50% bodyweight reduction resulted in a 51% reduction in maximum force and a 59% reduction in FTI in the heel, as compared with 19% to 28% at the metatarsal heads. There was reduced contact area in the heel and midfoot at and below 70% BW. Lower limb muscle activity decreases with reduced bodyweight while maintain normal muscle recruitment timing. CONCLUSIONS: The AG treadmill provides a reduction in loading forces while maintaining normal muscle recruitment patterns. Decreased BW running preferentially unloads the hindfoot. The AG treadmill can be an effective rehabilitation tool following foot or ankle injury and may prove superior to other limited weight-bearing methods.

7.
J Neuroeng Rehabil ; 21(1): 141, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39135048

RESUMEN

BACKGROUND: Patients with neurological disorders including stroke use rehabilitation to improve cognitive abilities, to regain motor function and to reduce the risk of further complications. Robotics-assisted tilt table technology has been developed to provide early mobilisation and to automate therapy involving the lower limbs. The aim of this study was to evaluate the feasibility of employing a feedback control system for heart rate (HR) during robotics-assisted tilt table exercise in patients after a stroke. METHODS: This feasibility study was designed as a case series with 12 patients ( n = 12 ) with no restriction on the time post-stroke or on the degree of post-stroke impairment severity. A robotics-assisted tilt table was augmented with force sensors, a work rate estimation algorithm, and a biofeedback screen that facilitated volitional control of a target work rate. Dynamic models of HR response to changes in target work rate were estimated in system identification tests; nominal models were used to calculate the parameters of feedback controllers designed to give a specified closed-loop bandwidth; and the accuracy of HR control was assessed quantitatively in feedback control tests. RESULTS: Feedback control tests were successfully conducted in all 12 patients. Dynamic models of heart rate response to imposed work rate were estimated with a mean root-mean-square (RMS) model error of 2.16 beats per minute (bpm), while highly accurate feedback control of heart rate was achieved with a mean RMS tracking error (RMSE) of 2.00 bpm. Control accuracy, i.e. RMSE, was found to be strongly correlated with the magnitude of heart rate variability (HRV): patients with a low magnitude of HRV had low RMSE, i.e. more accurate HR control performance, and vice versa. CONCLUSIONS: Feedback control of heart rate during robotics-assisted tilt table exercise was found to be feasible. Future work should investigate robustness aspects of the feedback control system. Modifications to the exercise modality, or alternative modalities, should be explored that allow higher levels of work rate and heart rate intensity to be achieved.


Asunto(s)
Terapia por Ejercicio , Estudios de Factibilidad , Frecuencia Cardíaca , Robótica , Rehabilitación de Accidente Cerebrovascular , Humanos , Frecuencia Cardíaca/fisiología , Rehabilitación de Accidente Cerebrovascular/métodos , Rehabilitación de Accidente Cerebrovascular/instrumentación , Masculino , Robótica/métodos , Robótica/instrumentación , Femenino , Persona de Mediana Edad , Anciano , Terapia por Ejercicio/métodos , Terapia por Ejercicio/instrumentación , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatología , Biorretroalimentación Psicológica/métodos , Biorretroalimentación Psicológica/instrumentación , Adulto
8.
Artículo en Inglés | MEDLINE | ID: mdl-39109606

RESUMEN

BACKGROUND: The use of fertility indicators to predict ovulation has largely been studied for contraceptive purposes, while less so as fertility-promoting tools. OBJECTIVE: To investigate the association between fertility indicators and fecundability in Danish women trying to conceive. METHODS: Web-based preconception cohort study. We analysed data from 11,328 females aged 18-49 years trying to conceive without fertility treatment for ≤6 menstrual cycles, from the Danish SnartGravid.dk and SnartForældre.dk cohorts (2007-2023). Participants reported the use of fertility indicators (counting days since the last menstrual period, cervical fluid monitoring, urinary ovulation testing, feeling ovulation, using a smartphone fertility app and measuring basal body temperature [BBT]). Time to pregnancy was measured in menstrual cycles ascertained by self-reported pregnancy status. We estimated fecundability ratios (FR) and 95% confidence intervals (CIs) using proportional probabilities regression models adjusted for age, socio-economic position, health indicators, reproductive history and gynaecological factors. RESULTS: Fertility indicators were used by 63.3% of participants at study entry. Counting days was the most common (46.9%), while measuring BBT was the least (3.0%). Other indicators ranged from 17.0% to 23.6%, with 69.7% using more than one indicator. Compared with non-use, use of any fertility indicator was associated with greater fecundability (adjusted FR 1.14, 95% CI 1.08, 1.19). Cervical fluid monitoring showed the strongest association (aFR 1.46, 95% CI 1.03, 2.07), followed by urinary ovulation testing (aFR 1.35, 95% CI 1.16, 1.58) and counting days (aFR 1.18, 95% CI 1.09, 1.29). Feeling ovulation and fertility apps were modestly associated with fecundability, while measuring BBT was not associated. Sensitivity analysis restricting to ≤2 cycles of attempt time and two cycles of follow-up showed an aFR for any indicator use of 1.21 (95% CI 1.13, 1.31). CONCLUSION: In this Danish preconception cohort, use of fertility indicators was associated with a higher fecundability, varying by type of indicator.

9.
J Chem Theory Comput ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110603

RESUMEN

Even though single hydrated electrons (ehyd-'s) are stable in liquid water, two hydrated electrons can bimolecularly react with water to create H2 and hydroxide: ehyd- + ehyd- + 2H2O → H2 + 2OH-. The rate of this reaction has an unusual temperature and isotope dependence as well as no dependence on ionic strength, which suggests that cosolvation of two electrons as a single hydrated dielectron (e2,hyd2-) might be an important intermediate in the mechanism of this reaction. Here, we present an ab initio density functional theory study of this reaction to better understand the potential properties, reactivity, and experimental accessibility of hydrated dielectrons. Our simulations create hydrated dielectrons by first simulating single ehyd-'s and then injecting a second electron, providing a well-defined time zero for e2,hyd2- formation and offering insight into a potential experimental route to creating dielectrons and optically inducing the reaction. We find that e2,hyd2- immediately forms in every member of our ensemble of trajectories, allowing us to study the molecular mechanism of H2 and OH- formation. The subsequent reaction involves separate proton transfer steps with a generally well-defined hydride subintermediate. The time scales for both proton transfer steps are quite broad, with the first proton transfer step spanning times over a few ps, while the second proton transfer step varies over ∼150 fs. We find that the first proton transfer rate is dictated by whether or not the reacting water is part of an H-bond chain that allows the newly created OH- to rapidly move by Grotthuss-type proton hopping to minimize electrostatic repulsion with H-. The second proton transfer step depends significantly on the degree of solvation of H-, leading to a wide range of reactive geometries where the two waters involved can lie either across the dielectron cavity or more adjacent to each other. This also allows the two proton transfer events to take place either effectively concertedly or sequentially, explaining differing views that have been presented in the literature.

10.
JMIR Rehabil Assist Technol ; 11: e57953, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093610

RESUMEN

BACKGROUND: Low back pain (LBP) is a significant public health problem that can result in physical disability and financial burden for the individual and society. Physical therapy is effective for managing LBP and includes evaluation of posture and movement, interventions directed at modifying posture and movement, and prescription of exercises. However, physical therapists have limited tools for objective evaluation of low back posture and movement and monitoring of exercises, and this evaluation is limited to the time frame of a clinical encounter. There is a need for a valid tool that can be used to evaluate low back posture and movement and monitor exercises outside the clinic. To address this need, a fabric-based, wearable sensor, Motion Tape (MT), was developed and adapted for a low back use case. MT is a low-profile, disposable, self-adhesive, skin-strain sensor developed by spray coating piezoresistive graphene nanocomposites directly onto commercial kinesiology tape. OBJECTIVE: The objectives of this study were to (1) validate MT for measuring low back posture and movement and (2) assess the acceptability of MT for users. METHODS: A total of 10 participants without LBP were tested. A 3D optical motion capture system was used as a reference standard to measure low back kinematics. Retroreflective markers and a matrix of MTs were placed on the low back to measure kinematics (motion capture) and strain (MT) simultaneously during low back movements in the sagittal, frontal, and axial planes. Cross-correlation coefficients were calculated to evaluate the concurrent validity of MT strain in reference motion capture kinematics during each movement. The acceptability of MT was assessed using semistructured interviews conducted with each participant after laboratory testing. Interview data were analyzed using rapid qualitative analysis to identify themes and subthemes of user acceptability. RESULTS: Visual inspection of concurrent MT strain and kinematics of the low back indicated that MT can distinguish between different movement directions. Cross-correlation coefficients between MT strain and motion capture kinematics ranged from -0.915 to 0.983, and the strength of the correlations varied across MT placements and low back movement directions. Regarding user acceptability, participants expressed enthusiasm toward MT and believed that it would be helpful for remote interventions for LBP but provided suggestions for improvement. CONCLUSIONS: MT was able to distinguish between different low back movements, and most MTs demonstrated moderate to high correlation with motion capture kinematics. This preliminary laboratory validation of MT provides a basis for future device improvements, which will also involve testing in a free-living environment. Overall, users found MT acceptable for use in physical therapy for managing LBP.

11.
J Pediatr Orthop ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39099047

RESUMEN

BACKGROUND: Hip surveillance in cerebral palsy (CP) is an accepted practice with evidence-based guidelines implemented. For the skeletally immature with open triradiate cartilage (TRC), recommendations for radiographic surveillance stemmed from population-based studies. For nonambulatory CP, progression of hip displacement after skeletal maturity has been reported; less is known for ambulatory CP. We aimed to determine the prevalence and risk factors associated with progressive hip displacement after TRC closure, a proxy for skeletal maturity, for ambulatory CP. METHODS: This is a retrospective cohort study of patients with ambulatory CP (Gross Motor Function Classification System I-III), with unilateral or bilateral involvement, hypertonic motor type, regular hip surveillance (≥3 radiographs after age 10 yr, 1 before TRC closure, ≥1 after age 16 yr), and 2-year follow-up post-TRC closure. The primary outcome was migration percentage (MP). Other variables included previous preventative/reconstructive surgery, topographic pattern, sex, scoliosis, epilepsy, and ventriculoperitoneal shunt. An "unsuccessful hip" was defined by MP ≥30%, MP progression ≥10%, and/or requiring reconstructive surgery after TRC closure. Statistical analyses included chi-square and multivariate Cox regression. Kaplan-Meier survivorship curves were also determined. Receiver operating characteristic analysis was used to determine the MP threshold for progression to an "unsuccessful hip" after TRC closure. RESULTS: Seventy-six patients (39.5% female) met the inclusion criteria, mean follow-up 4.7±2.1 years after TRC closure. Sixteen (21.1%) patients had an unsuccessful hip outcome. By chi-square analysis, diplegia (P=0.002) and epilepsy (P=0.04) were risk factors for an unsuccessful hip. By multivariate analysis, only first MP after TRC closure (P<0.001) was a significant risk factor for progression to an unsuccessful hip; MP ≥28% being the determined threshold (receiver operating characteristic curve analysis, area under curve: 0.845, P<0.02). CONCLUSIONS: The risk of MP progression after skeletal maturity is relatively high (21%), similar to nonambulatory CP. Annual hip surveillance radiographs after TRC closure should continue for Gross Motor Function Classification System I-III with an MP ≥28% after TRC closure, especially for bilateral CP and epilepsy. LEVEL OF EVIDENCE: III.

12.
Heliyon ; 10(12): e32624, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38975149

RESUMEN

The treatment for stage III melanoma has advanced significantly, nevertheless, a substantial proportion of patients experience relapse. Neoadjuvant immune checkpoint blockade has emerged as a promising approach, allowing early micrometastatic disease treatment, reduction of tumor burden before surgery, and enhanced tumor-specific T-cell responses. However, not all patients respond to treatment, highlighting the need for understanding immune mechanisms behind failure and identification of predictive markers. Here we performed a robust evaluation of systemic and tumoral immune profiles in a well-defined cohort of advanced melanoma patients treated with immune checkpoint inhibitors. Elevated CTACK and CXCL9 chemokines pre-treatment suggested their potential as predictive tools for treatment response. Furthermore, CD95 expression in CD8+ T lymphocytes surfaced as a favorable prognostic indicator, while PD-1, CD161, and PD-L2 exhibited correlations with worst outcomes. These findings shed light on the intricate interplay between immune markers and melanoma response to neoadjuvant immune checkpoint therapy, offering insights into personalized treatment strategies.

13.
Health Serv Res ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38965913

RESUMEN

OBJECTIVE: To illustrate the importance of a multidimensional view of disparities in quality of antidepressant medication management (AMM), as well as discriminating "within-facility" disparities from disparities that exist between facilities. DATA SOURCES AND STUDY SETTING: We used data from the Veterans Health Administration's (VA) Corporate Data Warehouse (CDW) which contains clinical and administrative data from VA facilities nationally. STUDY DESIGN: CDW data were used to measure five indicators of AMM quality, including the HEDIS Effective Acute-Phase and Effective Continuation-Phase measures. Mixed effects regression models were used to examine differences in quality indicators between racial/ethnic groups, controlling for other demographic and clinical factors. An adaptation of the Kitagawa-Blinder-Oaxaca (KBO) method was used to decompose mean differences in treatment quality between racial and ethnic groups into within- and between-facility effects. DATA EXTRACTION METHODS: Demographic, clinical, and health service utilization data were extracted for patients in fiscal year 2017 with a diagnosis of depression and a new start of an antidepressant medication. PRINCIPAL FINDINGS: The decomposition of the overall differences between White and Black patients on receiving an initial 90-day prescription (46.7% vs. 32.7%), Effective Acute-Phase (79.7% vs. 66.8%), and Effective Continuation-Phase (64.0% vs. 49.6%) HEDIS measures revealed that most of the overall effects were "within-facility," meaning that Black patients are less likely to meet these measures regardless of where they are treated. Although the overall magnitude of disparities between White and Hispanic patients on these three measures was very similar (46.7% vs. 32.7%; 79.7% vs. 69.2%; 64.0% vs. 53.6%), the differences were more attributable to Hispanic patients being treated in facilities with overall lower performance on these measures. CONCLUSIONS: Discriminating within- and between-facility disparities and taking a multidimensional view of quality are essential to informing efforts to address disparities in AMM quality.

14.
Ann Surg ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38979600

RESUMEN

OBJECTIVE: We characterized the quality of statistical methods for studies of racial and ethnic disparities in the surgical-relevant literature during 2021-2022. BACKGROUND: Hundreds of scientific papers are published each year describing racial and ethnic disparities in surgical access, quality, and outcomes. The content and design quality of this literature has never been systematically reviewed. METHODS: We searched for 2021-2022 studies focused on describing racial and/or ethnic disparities in surgical or perioperative access, process quality, or outcomes. Identified studies were characterized in terms of three methodological criteria: 1) adjustment for variables related to both race/ethnicity and outcomes, including social determinants of health (SDOH); 2) accounting for clustering of patients within hospitals or other subunits ("providers") and; 3) distinguishing within- and between-provider effects. RESULTS: We identified 224 papers describing racial and/or ethnic differences. Of the 38 single institution studies, 24 (63.2%) adjusted for at least one SDOH variable. Of the 186 multisite studies, 113 (60.8%) adjusted for at least one SDOH variable, and 43 (23.1%) accounted for clustering of patients within providers using appropriate statistical methods. Only 10 (5.4%) of multi-institution studies made efforts to examine how much of overall disparities were driven by within versus between provider effects. CONCLUSIONS: Most recently published papers on racial and ethnic disparities in the surgical literature do not meet these important statistical design criteria and therefore may risk inaccuracy in the estimation of group differences in surgical access, quality, and outcomes. The most potent leverage points for these improvements are changes to journal publication guidelines and policies.

15.
medRxiv ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38947087

RESUMEN

Post-Acute Sequelae of SARS-CoV-2 infection (PASC), also known as Long-COVID, encompasses a variety of complex and varied outcomes following COVID-19 infection that are still poorly understood. We clustered over 600 million condition diagnoses from 14 million patients available through the National COVID Cohort Collaborative (N3C), generating hundreds of highly detailed clinical phenotypes. Assessing patient clinical trajectories using these clusters allowed us to identify individual conditions and phenotypes strongly increased after acute infection. We found many conditions increased in COVID-19 patients compared to controls, and using a novel method to associate patients with clusters over time, we additionally found phenotypes specific to patient sex, age, wave of infection, and PASC diagnosis status. While many of these results reflect known PASC symptoms, the resolution provided by this unprecedented data scale suggests avenues for improved diagnostics and mechanistic understanding of this multifaceted disease.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38996209

RESUMEN

INTRODUCTION: The surgical management of severe scoliosis in patients with osteogenesis imperfecta (OI) is challenging because of curve rigidity, small stature, and inherent bone fragility. This study evaluated the midterm outcomes of our multimodal approach to address these issues, integrating perioperative bisphosphonate therapy, preoperative/intraoperative traction, various osteotomies, segmental pedicle screw instrumentation with cement augmentation, and bone morphogenetic protein-2 application. METHODS: A single-center retrospective review of 30 patients (average age 14.1 ± 2.2 years; 18 were female) diagnosed with OI and scoliosis was conducted. These patients underwent posterior spinal fusion between 2008 and 2020 and completed a minimum follow-up of 2 years. We measured radiographic parameters at each visit and reviewed the incidence of complications. A mixed-effects model was used to evaluate changes in radiographic parameters from preoperative measurements to the first and latest follow-ups. RESULTS: The patient cohort consisted of 2 individuals with type I OI, 20 with type III, 6 with type IV, and 2 with other types (types V and VIII). Surgical intervention led to a notable improvement in the major curve magnitude from 76° to 36°, with no notable correction loss. In addition, the minor curve, apical vertical translation, lowest instrumented vertebra tilt, and pelvic obliquity were also improved. In the sagittal plane, thoracic kyphosis and lumbar lordosis remained unchanged while thoracolumbar kyphosis markedly improved. Two patients experienced proximal junctional kyphosis with screw pullout, one of whom required revision surgery. One patient developed a superficial infection that was successfully treated with oral antibiotics. No instances of neurologic deficits or cement extravasation were observed. DISCUSSION: This study demonstrated the effectiveness and safety of our multimodal approach to treating scoliosis in patients with OI, achieving a 53% major curve correction with minimal complications over 2-year follow-up. These findings provide notable insights into managing scoliosis in this population. LEVEL OF EVIDENCE: Level IV (case series).

17.
Nat Commun ; 15(1): 5554, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987543

RESUMEN

Thermophilization is the directional change in species community composition towards greater relative abundances of species associated with warmer environments. This process is well-documented in temperate and Neotropical plant communities, but it is uncertain whether this phenomenon occurs elsewhere in the tropics. Here we extend the search for thermophilization to equatorial Africa, where lower tree diversity compared to other tropical forest regions and different biogeographic history could affect community responses to climate change. Using re-census data from 17 forest plots in three mountain regions of Africa, we find a consistent pattern of thermophilization in tree communities. Mean rates of thermophilization were +0.0086 °C·y-1 in the Kigezi Highlands (Uganda), +0.0032 °C·y-1 in the Virunga Mountains (Rwanda-Uganda-Democratic Republic of the Congo) and +0.0023 °C·y-1 in the Udzungwa Mountains (Tanzania). Distinct from other forests, both recruitment and mortality were important drivers of thermophilzation in the African plots. The forests studied currently act as a carbon sink, but the consequences of further thermophilization are unclear.


Asunto(s)
Cambio Climático , Bosques , Árboles , Clima Tropical , Biodiversidad , Temperatura , Uganda , Tanzanía , Rwanda , República Democrática del Congo , Secuestro de Carbono
18.
Artículo en Inglés | MEDLINE | ID: mdl-39037277

RESUMEN

OBJECTIVES: Hypoperfusion and tissue hypoxia have been implicated as contributory mechanisms in the neuropathology of multiple sclerosis (MS). Our objective has been to study cortical oxygenation in vivo in patients with MS and age-matched controls. METHODS: A custom, multiwavelength time-domain near-infrared spectroscopy system was developed for assessing tissue hypoxia from the prefrontal cortex. A cross-sectional case-control study was undertaken assessing patients with secondary progressive MS (SPMS) and age-matched controls. Co-registered magnetic resonance imaging was used to verify the location from which near-infrared spectroscopy data were obtained through Monte Carlo simulations of photon propagation. Additional clinical assessments of MS disease severity were carried out by trained neurologists. Linear mixed effect models were used to compare cortical oxygenation between cases and controls, and against measures of MS severity. RESULTS: Thirty-three patients with secondary progressive MS (median expanded disability status scale 6 [IQR: 5-6.5]; median age 53.0 [IQR: 49-58]) and 20 age-matched controls were recruited. Modeling of photon propagation confirmed spectroscopy data were obtained from the prefrontal cortex. Patients with SPMS had significantly lower cortical hemoglobin oxygenation compared with controls (-6.0% [95% CI: -10.0 to -1.9], P = 0.004). There were no significant associations between cortical oxygenation and MS severity. INTERPRETATION: Using an advanced, multiwavelength time-domain near-infrared spectroscopy system, we demonstrate that patients with SPMS have lower cortical oxygenation compared with controls.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39024049

RESUMEN

OBJECTIVES: To examine the clinicopathologic features of patients with polymyalgia rheumatica (PMR) who had thoracic aorta repair surgery. Findings were compared with those of a cohort of patients with giant cell arteritis (GCA) requiring thoracic aorta repair. METHODS: All patients evaluated at Mayo Clinic in Rochester, MN, with Current Procedural Terminology (CPT) codes for thoracic aorta repair surgery between 2000- 2021 were identified. All patients were screened for prior PMR diagnosis. Patients with PMR and no signs of GCA were categorized as clinically isolated PMR. The medical records of all patients were manually reviewed, and pathologists re-examined all the aortic tissues. RESULTS: Of the 4621 patients with at least one CPT code for thoracic aorta repair surgery, 43 patients were diagnosed with clinically isolated PMR before the surgery. Detailed histopathological examination of the aortic tissues revealed active inflammation in 30/43 (70%) patients after a median (IQR) of 10.0 (4.7- 13.3) years from the PMR diagnosis. When compared with aortic tissue from patients with a prior diagnosis of GCA, the aorta of patients with PMR had more severe inflammation (Grade 3: 15/30 [50%] vs 5/34 [15%], p= 0.002). Patients with PMR and thoracic aorta repair may experience a 40% increased risk of mortality compared with the general population, but this did not reach statistical significance (standardized mortality ratio: 1.40; 95% CI: 0.91- 2.07). CONCLUSIONS: Some patients with PMR have subclinical aortic inflammation that is detectable many years after initial diagnosis and may contribute to the development of aortic aneurysm.

20.
Fam Med Community Health ; 12(Suppl 2)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39029926

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer death in US adults but can be reduced by screening. The roles of individual and contextual factors, and especially physician supply, in attaining universal CRC screening remains uncertain. METHODS: We used data from adults 50-75 years old participating in the 2018 New York (NY) Behavioural Risk Factor Surveillance System linked to county-level covariates, including primary care physician (PCP) density and gastroenterologist (GI) density. Data were analysed in 2023-2024. Our analyses included (1) ecological and geospatial analyses of county-level CRC screening prevalence and (2) individual-level Poisson regression models of receipt of screening, adjusted for socioeconomic and county-level contextual variables. RESULTS: Mean prevalence of up-to-date CRC screening was 71% (95% CI 70% to 73%) across NY's 62 counties. County-level CRC screening demonstrated significant spatial patterning (Global Moran's I=0.14, p=0.04), consistent with the existence of county-level contextual factors. In both county-level and individual-level analyses, lack of health insurance was associated with lower likelihood of up-to-date screening (ß=-1.09 (95% CI -2.00 to -0.19); adjusted prevalence ratio 0.68 (95% CI 0.60 to 0.77)), even accounting for age, race/ethnicity and education. In contrast, county-level densities of both PCPs and GIs were completely unassociated with screening at either the county or individual level. As expected, other determinants at the individual level included education status and age. CONCLUSION: In this state-wide representative analysis, physician density was completely unassociated with CRC screening, although health insurance status remains strongly related. In similar screening environments, broadened insurance coverage for CRC screening is likely to improve screening far more effectively than increased physician supply.


Asunto(s)
Neoplasias Colorrectales , Detección Precoz del Cáncer , Humanos , Neoplasias Colorrectales/diagnóstico , Persona de Mediana Edad , Anciano , Detección Precoz del Cáncer/estadística & datos numéricos , Masculino , Femenino , New York , Sistema de Vigilancia de Factor de Riesgo Conductual , Análisis Espacial , Factores Socioeconómicos , Médicos de Atención Primaria
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