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1.
Phys Chem Chem Phys ; 26(16): 12483-12494, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38619858

RESUMEN

The MP2 and CCSD(T) methods are paired with correlation consistent basis sets as large as aug-cc-pVQZ to optimize the structures of the cyclic minima for (HF)n, (HCl)n and (H2O)n where n = 3-5, as well as the corresponding transition states (TSs) for concerted proton transfer (CPT). MP2 and CCSD(T) harmonic vibrational frequencies confirm the nature of each minimum and TS. Both conventional and explicitly correlated CCSD(T) computations are employed to assess the electronic dissociation energies and barrier heights for CPT near the complete basis (CBS) limit for all 9 clusters. Results for (HF)n are consistent with prior studies identifying Cnh and Dnh point group symmetry for the minima and TSs, respectively. Our computations also confirm that CPT proceeds through Cs TS structures for the C1 minima of (H2O)3 and (H2O)5, whereas the process goes through a TS with D2d symmetry for the S4 global minimum of (H2O)4. This work corroborates earlier findings that the minima for (HCl)3, (HCl)4 and (HCl)5 have C3h, S4 and C1 point group symmetry, respectively, and that the Cnh structures are not minima for n = 4 and 5. Moreover, our computations show the TSs for CPT in (HCl)3, (HCl)4 and (HCl)5 have D3h, D2d, and C2 point group symmetry, respectively. At the CCSD(T) CBS limit, (HF)4 and (HF)5 have the smallest electronic barrier heights for CPT (≈15 kcal mol-1 for both), followed by the HF trimer (≈21 kcal mol-1). The barriers are appreciably higher for the other clusters (around 27 kcal mol-1 for (H2O)4 and (HCl)3; roughly 30 kcal mol-1 for (H2O)3, (H2O)5 and (HCl)4; up to 38 kcal mol-1 for (HCl)5). At the CBS limit, MP2 significantly underestimates the CCSD(T) barrier heights (e.g., by ca. 2, 4 and 7 kcal mol-1 for the pentamers of HF, H2O and HCl, respectively), whereas CCSD overestimates these barriers by roughly the same magnitude. Scaling the barrier heights and dissociation energies by the number of fragments in the cluster reveals strong linear relationships between the two quantities and with the magnitudes of the imaginary vibrational frequency for the TSs.

2.
Pain Manag ; 14(2): 75-85, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38314568

RESUMEN

Aim: Chronic low back pain represents a significant societal problem leading to increased healthcare costs and quality of life. This study was designed to evaluate the feasibility and effectiveness of non-invasive spinal electromagnetic simulation (SEMS) to treat nonspecific chronic low back pain (CLBP). Methods: A single-site prospective study was conducted to evaluate SEMS in reducing pain and improving disability. A total of 17 patients received SEMS two to three sessions a week. The Numeric Rating Scale and the Modified Oswestry Disability Questionnaire were used to assess pain and disability. Results: Participants receiving SEMS exhibited statistically significant reductions in pain and disability. Conclusion: Current results suggest that non-invasive SEMS can be an effective treatment in reducing pain and improving disability associated with CLBP.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Veteranos , Humanos , Dolor de la Región Lumbar/terapia , Estudios de Factibilidad , Calidad de Vida , Estudios Prospectivos , Dolor de Espalda , Resultado del Tratamiento , Fenómenos Magnéticos , Dolor Crónico/terapia
3.
Allergy Asthma Clin Immunol ; 19(1): 105, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082409

RESUMEN

BACKGROUND: Real-world data on subcutaneous C1INH (C1INH[SC]) usage and patient-level impacts on hereditary angioedema (HAE)-related outcomes and quality of life (QoL) are both lacking and challenging to generate using conventional study methodologies. Using a hybrid study design involving patient interviews supplemented by retrospective medical chart data review, we conducted a real-world assessment of the impact of C1INH(SC) prophylaxis on HAE attack patterns, QoL, and on-demand medication use. METHODS: The study was conducted at seven US sites and included 36 adults with HAE who had been treated with C1INH(SC) long-term prophylaxis following ≥ 12 months of on-demand management only. Patients underwent 30-min interviews, facilitated and analyzed by a trained qualitative research specialist. Medical records were reviewed for 12 months before (pre-index) and after (post-index) initiation of C1INH(SC). Using interview data with descriptive terms converted to numerical values, we compared pre- versus post-index attack frequency, severity, and rescue medication usage. RESULTS: Mean (SD) annualized attack frequency per patient decreased 82.0%, from 38.8 (38.8) attacks/year pre-index to 7.0 (15.3) attacks/year (P < 0.001); the median number of attacks decreased by 97.0% (30 pre-index to 1 post-index). For 20 patients, the annualized attack rate after starting C1INH(SC) prophylaxis was ≤ 1 attack/year; 12 of these patients reported 0 attacks. Mean (SD) attack severity (scale: 0 = none/mild to 4 = very severe) decreased from 2.3 (0.7) pre-index to 0.9 (0.9) post-index (P < 0.001). Mean/median rescue medication use decreased by 77.2%/96.3%. Improved QoL was narratively described for many domains. CONCLUSIONS: These real-world findings indicate that long-term prophylaxis with C1INH(SC) markedly improves important factors that contribute to the goal of achieving total disease control and normalization of patients' lives, including fewer and less severe attacks, less rescue medication usage, and improved QoL.

4.
ACS Appl Mater Interfaces ; 15(47): 54942-54951, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37973616

RESUMEN

Nanochannels with controllable gating behavior are attractive features in a wide range of nanofluidic applications including viral detection, particle sorting, and flow regulation. Here, we use selective sidewall functionalization of nanochannels with a polyelectrolyte brush to investigate the channel gating response to variations in solution pH and ionic strength. The conformational and structural changes of the interfacial brush layer within the channels are interrogated by specular and off-specular neutron reflectometry. Simultaneous fits of the specular and off-specular signals, using a dynamical theory model and a fitting optimization protocol, enable detailed characterization of the brush conformations and corresponding channel geometry under different solution conditions. Our results indicate a collapsed brush state under basic pH, equivalent to an open gate, and an expanded brush state representing a partially closed gate upon decreasing the pH and salt concentration. These findings open new possibilities in noninvasive in situ characterization of tunable nanofluidics and lab-on-chip devices with advanced designs and improved functionality.

5.
Qual Manag Health Care ; 32(2): 87-93, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36007128

RESUMEN

BACKGROUND: There exists an array of quality performance measures for nursing homes. They can confuse consumers, administrators, and government regulators. Our methodology provides a unified multidimensional evaluation. OBJECTIVE: To present a methodology to perform a multidimensional assessment of each nursing home within any specified group of nursing homes to aid policy makers, administrators, and consumers with a clear, easy-to-interpret evaluation of a nursing home quality performance. METHODS: We use data envelopment analysis (DEA) to integrate several quality measures into a comprehensive benchmarking model. We present statewide results comparing DEA performance scores with the Five-Star rating using data from New York State (NYS) Department of Health. RESULTS: In total, 212 of the 526 nursing homes performed as well as possible. Public nursing homes are most likely to lie on the frontier and have the highest average performance scores. The relationship between the DEA-based performance scores and the NYS Five-Star quality ratings is very weak. CONCLUSION: DEA is a comprehensive methodology for measuring nursing home quality. The DEA factor performance scores provide detailed information for individual nursing homes, enabling administrators to benchmark their facility's quality performance and to focus quality improvement efforts more effectively.


Asunto(s)
Ciencia de los Datos , Casas de Salud , Humanos , Estados Unidos , Benchmarking , Mejoramiento de la Calidad , Calidad de la Atención de Salud
6.
J Cell Sci ; 135(7)2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35362516

RESUMEN

The histone variant macroH2A1.1 plays a role in cancer development and metastasis. To determine the underlying molecular mechanisms, we mapped the genome-wide localization of endogenous macroH2A1.1 in the human breast cancer cell line MDA-MB-231. We demonstrate that macroH2A1.1 specifically binds to active promoters and enhancers in addition to facultative heterochromatin. Selective knock down of macroH2A1.1 deregulates the expression of hundreds of highly active genes. Depending on the chromatin landscape, macroH2A1.1 acts through two distinct molecular mechanisms. The first mitigates excessive transcription by binding over domains including the promoter and the gene body. The second stimulates expression of RNA polymerase II (Pol II)-paused genes, including genes regulating mammary tumor cell migration. In contrast to the first mechanism, macroH2A1.1 specifically associates with the transcription start site of Pol II-paused genes. These processes occur in a predefined local 3D genome landscape, but do not require rewiring of enhancer-promoter contacts. We thus propose that macroH2A1.1 serves as a transcriptional modulator with a potential role in assisting the conversion of promoter-locked Pol II into a productive, elongating Pol II.


Asunto(s)
Cromatina , ARN Polimerasa II , Cromatina/genética , Histonas/genética , Histonas/metabolismo , Humanos , Regiones Promotoras Genéticas/genética , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos
7.
Blood ; 139(24): 3505-3518, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35316324

RESUMEN

Oncogenic alterations underlying B-cell acute lymphoblastic leukemia (B-ALL) in adults remain incompletely elucidated. To uncover novel oncogenic drivers, we performed RNA sequencing and whole-genome analyses in a large cohort of unresolved B-ALL. We identified a novel subtype characterized by a distinct gene expression signature and the unique association of 2 genomic microdeletions. The 17q21.31 microdeletion resulted in a UBTF::ATXN7L3 fusion transcript encoding a chimeric protein. The 13q12.2 deletion resulted in monoallelic ectopic expression of the homeobox transcription factor CDX2, located 138 kb in cis from the deletion. Using 4C-sequencing and CRISPR interference experiments, we elucidated the mechanism of CDX2 cis-deregulation, involving PAN3 enhancer hijacking. CDX2/UBTF ALL (n = 26) harbored a distinct pattern of additional alterations including 1q gain and CXCR4 activating mutations. Within adult patients with Ph- B-ALL enrolled in GRAALL trials, patients with CDX2/UBTF ALL (n = 17/723, 2.4%) were young (median age, 31 years) and dramatically enriched in females (male/female ratio, 0.2, P = .002). They commonly presented with a pro-B phenotype ALL and moderate blast cell infiltration. They had poor response to treatment including a higher risk of failure to first induction course (19% vs 3%, P = .017) and higher post-induction minimal residual disease (MRD) levels (MRD ≥ 10-4, 93% vs 46%, P < .001). This early resistance to treatment translated into a significantly higher cumulative incidence of relapse (75.0% vs 32.4%, P = .004) in univariate and multivariate analyses. In conclusion, we discovered a novel B-ALL entity defined by the unique combination of CDX2 cis-deregulation and UBTF::ATXN7L3 fusion, representing a high-risk disease in young adults.


Asunto(s)
Factor de Transcripción CDX2 , Proteínas del Complejo de Iniciación de Transcripción Pol1 , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Factores de Transcripción , Adulto , Factor de Transcripción CDX2/genética , Femenino , Genes Homeobox , Humanos , Masculino , Neoplasia Residual/genética , Proteínas de Fusión Oncogénica , Proteínas del Complejo de Iniciación de Transcripción Pol1/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Factores de Transcripción/genética
8.
Int J Health Plann Manage ; 37(1): 352-360, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34585434

RESUMEN

OBJECTIVE: We propose an alternative to the Risk Adjusted Mortality Rate (RAMR), about which we identify four serious concerns. We apply our method to cardiac surgery. DESIGN: We present a methodology that uses the upper and lower tail probabilities (UTP/LTP) of the binomial distribution to screen for poor/high performing providers. STUDY SETTING: The New York State Department of Health (NYS DOH) publicly releases data on all cardiac surgery patients in the state. We download cardiac surgery data from the NYS DOH website for the years 2011 through 2013. The state's objective is to identify poorly performing hospitals and surgeons and thereby reduce deaths. NYS employs the RAMR. RESULTS: The UTP/LTP approach agrees with the RAMR in its classification of all 132 surgeons and all 40 hospitals. However, performance is a continuous construct and strict categorization can lead to failure to identify marginal providers. CONCLUSIONS: Our methodology addresses all four concerns regarding the RAMR. The UTP/LTP approach avoids inappropriate hypothesis testing and is consistent with standard statistical theory and practice in its approach to case volume. It does not require confidence intervals and it applies to all providers regardless of case volume.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Atención a la Salud , Servicios de Salud , Mortalidad Hospitalaria , Hospitales , Humanos , New York
9.
J Exp Bot ; 72(12): 4373-4383, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33735372

RESUMEN

Plateauing yield and stressful environmental conditions necessitate selecting crops for superior physiological traits with untapped potential to enhance crop performance. Plant productivity is often limited by carbon fixation rates that could be improved by increasing maximum photosynthetic carboxylation capacity (Vcmax). However, Vcmax measurements using gas exchange and biochemical assays are slow and laborious, prohibiting selection in breeding programs. Rapid hyperspectral reflectance measurements show potential for predicting Vcmax using regression models. While several hyperspectral models have been developed, contributions from different spectral regions to predictions of Vcmax have not been clearly identified or linked to biochemical variation contributing to Vcmax. In this study, hyperspectral reflectance data from 350-2500 nm were used to build partial least squares regression models predicting in vivo and in vitro Vcmax. Wild-type and transgenic tobacco plants with antisense reductions in Rubisco content were used to alter Vcmax independent from chlorophyll, carbon, and nitrogen content. Different spectral regions were used to independently build partial least squares regression models and identify key regions linked to Vcmax and other leaf traits. The greatest Vcmax prediction accuracy used a portion of the shortwave infrared region from 2070 nm to 2470 nm, where the inclusion of fewer spectral regions resulted in more accurate models.


Asunto(s)
Nicotiana , Fitomejoramiento , Clorofila , Fotosíntesis , Hojas de la Planta
10.
J Plant Physiol ; 258-259: 153357, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33465638

RESUMEN

Canopy water use efficiency (above-ground biomass over lifetime water loss, WUEcanopy) can influence yield in wheat and other crops. Breeding for WUEcanopy is difficult because it is influenced by many component traits. For example, intrinsic water use efficiency (WUEi), the ratio of net carbon assimilation (Anet) over stomatal conductance, contributes to WUEcanopy and can be estimated from carbon isotope discrimination (Δ). However, Δ is not sensitive to differences in the water vapor pressure deficit between the air and leaf (VPDleaf). Alternatively, measurements of instantaneous leaf water use efficiency (WUEleaf) are defined as Anet over transpiration and can be determined with gas exchange, but the dynamic nature of field conditions are not represented. Specifically, fluctuations in canopy temperature lead to changes in VPDleaf that impact transpiration but not Anet. This alters WUEleaf and in turn affects WUEcanopy. To test this relationship, WUEcanopy was measured in conjunction with WUEi, WUEcanopy, and canopy temperature under well-watered and water-limited conditions in two drought-tolerant wheat cultivars that differ in canopy architecture. In this experiment, boundary layer conductance was low and significant changes in leaf temperature occurred between cultivars and treatments that correlated with WUEcanopy likely because of the effect of canopy temperature on VPDleaf driving T. However, deviations between WUEi, WUEleaf, and WUEcanopy were present because measurements made at the leaf level do not account for variations in leaf temperature. This uncoupled the relationship of measured WUEleaf and WUEi from WUEcanopy and emphasizes the importance of canopy temperature on carbon uptake and transpired water loss.


Asunto(s)
Sequías , Hojas de la Planta/metabolismo , Temperatura , Triticum/metabolismo , Agua/metabolismo
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