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Solid-state nuclear magnetic resonance (SSNMR) and nuclear quadrupole resonance (NQR) spectra provide detailed information about the electronic and atomic structure of solids. Modern ab initio methods such as density functional theory (DFT) can be used to calculate NMR and NQR spectra from first-principles, providing a meaningful avenue to connect theory and experiment. Prediction of SSNMR and NQR spectra from DFT relies on accurate calculation of the electric field gradient (EFG) tensor associated with the potential of electrons at the nuclear centers. While static calculations of EFGs are commonly seen in the literature, the effects of dynamical motion of atoms in molecules and solids have been less explored. In this study, we develop a method to calculate EFGs of solids while taking into account the dynamics of atoms through DFT-based molecular dynamics simulations. The method we develop is general, in the sense that it can be applied to any material at any desired temperature and pressure. Here, we focus on application of the method to NaNO2 and study in detail the EFGs of 14N, 17O, and 23Na. We find in the cases of 14N and 17O that the dynamical motion of the atoms can be used to calculate mean EFGs that are in closer agreement with experiments than those of static calculations. For 23Na, we find a complex behavior of the EFGs when atomic motion is incorporated that is not at all captured in static calculations. In particular, we find a distribution of EFGs that is influenced strongly by the local (changing) bond environment, with a pattern that reflects the coordination structure of 23Na. We expect the methodology developed here to provide a path forward for understanding materials in which static EFG calculations do not align with experiments.
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In this article, we will review common pituitary disorders. There are 6 hormones secreted by the anterior pituitary gland: thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone, growth hormone, and prolactin. The posterior pituitary gland stores and releases the hormones made in the hypothalamus, oxytocin and antidiuretic hormone, based on the body's needs. This article will discuss the role of these hormones, conditions and symptoms that occur with elevated or reduced hormone levels, as well as the evaluation and treatment of these pituitary disorders.
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Enfermedades de la Hipófisis , Humanos , Enfermedades de la Hipófisis/diagnóstico , Enfermedades de la Hipófisis/terapia , Tirotropina/sangre , Hormona Folículo Estimulante/metabolismo , Prolactina/metabolismo , Atención Primaria de Salud , Hormona Luteinizante/metabolismo , Hormona Adrenocorticotrópica/metabolismoRESUMEN
Acupuncture is gaining popularity and wider acceptance as a treatment modality within the field of sports medicine. Our objective was to provide a comprehensive review of the existing literature pertaining to acupuncture in sports medicine to shed light on approaches utilized in acupuncture while revealing its personalized nature and its impact on athletes' preparation, performance, and recovery. We evaluated acupuncture research in the context of medicine and sports-related injury treatment, assessing its impact on athletic performance across demographics of athletes. Athletes participating in most sports have shown positive outcomes from acupuncture interventions. Acupuncture improves peak oxygen levels, maximum heart rate, delayed-onset muscle soreness, pain, swelling, explosive force production, and joint mobility. Furthermore, the efficacy of acupuncture appears to be similar regardless of age and sex. Lastly, the acceptance of acupuncture is influenced by cultural factors, with Western and traditional East Asian cultures exhibiting distinct perspectives on its rationale and mechanisms of action. Traditional East Asian acupuncturists typically employ qi and meridian theories in their acupuncture practices, with the recent incorporation of Western concepts. Acupuncture shows promise as an effective treatment for musculoskeletal pain and neuropathies in athletes across different age groups and for addressing injuries in various sports. Our comprehensive review will enhance our understanding of acupuncture's potential as a complementary or distinct therapeutic approach compared to conventional therapies. Additionally, our review explores its specific applications within different sports and delves into the cultural dimensions involved in integrating this practice into modern sports medicine.
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Terapia por Acupuntura , Acupuntura , Traumatismos en Atletas , Meridianos , Medicina Deportiva , Humanos , Medicina Deportiva/métodos , Terapia por Acupuntura/métodos , Traumatismos en Atletas/terapiaRESUMEN
There is growing interest in using low-field magnetic resonance experiments for routine chemical characterization. Earth's field NMR is one such technique that can garner structural information and enable sample differentiation with low cost and highly portable designs. The resulting NMR spectra are primarily influenced by J-couplings, resulting in so-called J-coupled spectra (JCS). Many small molecules include atoms with NMR-active nuclei that are quadrupolar either at natural abundance or are often isotopically enriched (e.g.,2H, 6Li, 11B, 14N, 17O, etc.) where the effects of quadrupolar J-couplings and relaxation on JCS of strongly- and weakly-coupled spin systems have not been explored to date. Herein, using a set of seven fluoropyridine samples with unique substitution and J-couplings, we demonstrate that the 14N relaxation rates can induce drastic line-broadening in the JCS. This includes a previously unexplored unique line broadening mechanism enabled by strongly coupled spins at low-field. Numerical simulations are used to model and refine the magnitudes and signs of J-couplings, as well as indirectly determine the 14N relaxation rates in a single 1D experiment that has a higher fidelity than observed in high-field NMR experiments.
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Radio frequency (RF) magnetometers based on nitrogen vacancy centers in diamond are predicted to offer femtotesla sensitivity, but previous experiments were limited to the picotesla level. We demonstrate a femtotesla RF magnetometer using a diamond membrane inserted between ferrite flux concentrators. The device provides ~300-fold amplitude enhancement for RF magnetic fields from 70 kHz to 3.6 MHz, and the sensitivity reaches ~70 fTâs at 0.35 MHz. The sensor detected the 3.6-MHz nuclear quadrupole resonance (NQR) of room-temperature sodium nitrite powder. The sensor's recovery time after an RF pulse is ~35 µs, limited by the excitation coil's ring-down time. The sodium-nitrite NQR frequency shifts with temperature as -1.00±0.02 kHz/K, the magnetization dephasing time is T2*=887±51 µs, and multipulse sequences extend the signal lifetime to 332±23 ms, all consistent with coil-based studies. Our results expand the sensitivity frontier of diamond magnetometers to the femtotesla range, with potential applications in security, medical imaging, and materials science.
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Diamante , Nitrógeno , Espectroscopía de Resonancia Magnética/métodos , TemperaturaRESUMEN
Human T cells have a diverse T-cell receptor (TCR) repertoire that endows them with the ability to identify and defend against a broad spectrum of antigens. The universe of possible antigens that T cells may encounter, however, is even larger. To effectively surveil such a vast universe, the T-cell repertoire must adopt a high degree of cross-reactivity. Likewise, antigen-specific and cross-reactive T-cell responses play pivotal roles in both protective and pathological immune responses in numerous diseases. In this review, we explore the implications of these antigen-driven T-cell responses, with a particular focus on CD8+ T cells, using infection, neurodegeneration, and cancer as examples. We also summarize recent technological advances that facilitate high-throughput profiling of antigen-specific and cross-reactive T-cell responses experimentally, as well as computational biology approaches that predict these interactions.
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Antígenos , Linfocitos T CD8-positivos , Humanos , Reacciones Cruzadas , Receptores de Antígenos de Linfocitos TRESUMEN
Linking antigen specificity to T cell receptor (TCR) sequences is critical, albeit challenging, to both understanding T cell biology and developing T cell-based therapeutics. Here, we describe in detail tetramer-associated TCR sequencing (TetTCR-Seq), a novel approach to tackling this challenge. TetTCR-Seq is accomplished by multiplexing DNA-barcoded peptide-MHC (pMHC) tetramers, allowing for simultaneous recall of antigen specificity and TCR sequences after single cell sequencing. Additionally, TetTCR-Seq simplifies labor and cuts cost by taking advantage of in vitro transcription and translation (IVTT) to generate peptide libraries and DNA barcodes, in parallel, from the same template. Thus, TetTCR-Seq is a powerful technology capable of quickly and affordably surveying the T cell repertoire for hundreds of antigen specificities in a single experiment.
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Receptores de Antígenos de Linfocitos T , Linfocitos T , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T/genéticaRESUMEN
Delirium, a common and serious disorder in older hospitalized patients, remains underrecognized. While several delirium predictive models have been developed, only a handful have focused on electronic health record (EHR) data. This prospective cohort study of older inpatients (≥65 years old) aimed to determine if variables within our health system's EHR could be used to identify delirium among hospitalized patients at the bedside. Trained researchers screened daily for delirium using the 3-minute diagnostic Confusion Assessment Method (3D-CAM). Patient demographic and clinical variables were extracted from the EHR. Among 408 participants, mean age was 75 years, 60.8% were female, and 82.6% were Black. Overall rate of delirium was 16.7%. Patients with delirium were older and more likely to have an infection diagnosis, prior dementia, higher Charlson comorbidity severity of illness score, lower Braden Scale score, and higher Morse Fall Scale score in the EHR (P<0.01 for all). On multivariable analysis, a prior diagnosis of dementia (odds ratio: 5.0, 95% CI: 2.5-10.3) and a Braden score of <18 (odds ratio: 2.8, 95% CI: 1.5-5.1) remained significantly associated with delirium among hospitalized patients. Further research in the development of an automated delirium prediction model is needed.
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BACKGROUND: The clinical benefits of Acute Care for Elders (ACE) units have been established for over 25 years. However, how widely disseminated ACE units are in the United States and the degree of fidelity to the key elements of this model of care are unknown. Our objective was to identify all existing ACE units in the United States and to obtain detailed information about variations in implementation. METHODS: The strategy to identify current ACE units began with online searches and snowball sampling using contacts from professional societies and workgroups. Next, a request for information regarding the existence of ACE units was sent to the remaining US hospitals listed in a national hospital database. An online survey was sent to identified ACE unit contacts to capture information on implementation characteristics and the five key elements of ACE units. RESULTS: There were 3692 hospitals in the database with responses from 2055 (56%) hospitals reporting the presence or absence of an ACE unit. We identified 68 hospitals (3.3%) with an existing or previous ACE unit. Of these 68 hospitals, 50 (74%) completed the survey and reported that 43 ACE units were currently open and 7 had been closed. Of the 43 currently open ACE units, most are affiliated with an academic hospital and there is variable implementation of each of the five key ACE elements (from 69% to 98%). CONCLUSIONS: Among the 50 hospitals to complete the survey, 43 current ACE units were identified, with variable fidelity to the key elements. Estimates of prevalence of ACE units and fidelity to key elements are limited by nonresponses to the national survey request by nearly half of hospitals.
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Cuidados Críticos , Hospitales , Anciano , Humanos , Encuestas y Cuestionarios , Estados UnidosRESUMEN
Follicular-helper T cells (TFH) are an essential arm of the adaptive immune system. Although TFH were first discovered through their ability to contribute to antibody affinity maturation through co-stimulatory interactions with B cells, new light has been shed on their ability to remain a complex and functionally plastic cell type. Due to a lack sample availability, however, many studies have been limited to characterizing TFH in mice or non-canonical tissue types, such as peripheral blood. Such constraints have resulted in a limited, and sometimes contradictory, understanding of this fundamental cell type. One subset of TFH receiving attention in chronic infection are CXCR3-expressing TFH cells (CXCR3+TFH) due to their abnormal accumulation in secondary lymphoid tissues. Their function and clonal relationship with other TFH subsets in lymphoid tissues during infection, however, remains largely unclear. We thus systematically investigated this and other subsets of TFH within untreated HIV-infected human lymph nodes using Mass CyTOF and a combination of RNA and TCR repertoire sequencing. We show an inflation of the CXCR3+TFH compartment during HIV infection that correlates with a lower HIV burden. Deeper analysis into this population revealed a functional shift of CXCR3+TFH away from germinal center TFH (GC-TFH), including the altered expression of several important transcription factors and cytokines. CXCR3+TFH also upregulated cell migration transcriptional programs and were clonally related to peripheral TFH populations. In combination, these data suggest that CXCR3+TFH have a greater tendency to enter circulation than their CXCR3- counterparts, potentially functioning through distinct modalities that may lead to enhanced defense.
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Infecciones por VIH , Células T Auxiliares Foliculares , Animales , Centro Germinal , Humanos , Ratones , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores CXCR3/genética , Receptores CXCR3/metabolismo , Linfocitos T Colaboradores-Inductores , TranscriptomaAsunto(s)
Delirio , Delirio/terapia , Hospitales , Humanos , Unidades de Cuidados Intensivos , Proyectos PilotoRESUMEN
Pediatric patients are frequently evaluated in primary care clinics. Thus, there exists a need to understand common pediatric problems and to acquire a degree of familiarity with pediatric procedures. This article will review techniques and the current evidence for frequently performed pediatric procedures, including umbilical granuloma chemocautery, frenotomy, suture ligation of type B postaxial polydactyly, reduction of nursemaid's elbow, hair tourniquet removal, and tympanometry.
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Articulación del Codo , Luxaciones Articulares , Polidactilia , Niño , Dedos , HumanosRESUMEN
The inherently quantitative nature of nuclear magnetic resonance (NMR) spectroscopy is one of the most attractive aspects of this analytical technique. Quantitative NMR analyses have typically been limited to high-field (>1 T) applications. The aspects for quantitation at low magnetic fields (<1 mT) have not been thoroughly investigated and are shown to be impacted by the complex signatures that arise at these fields from strong heteronuclear J-couplings. This study investigates quantitation at Earth's magnetic field (â¼50 µT) for a variety of samples in strongly, weakly, and uncoupled spin systems. To achieve accurate results in this regime, the instrumentation, experimental acquisition, processing, and theoretical aspects must be considered and reconciled. Of particular note is the constant field nuclear receptivity equation, which has been re-derived in this study to account for strong coupling and quality factor effects. The results demonstrate that the quantitation of homonuclear molecular groups, determination of heteronuclear pseudoempirical formulas, and mixture analysis are all feasible at Earth's magnetic field in a greatly simplified experimental system.
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Servicios de Salud para Ancianos , Médicos , Anciano , Humanos , Calidad de la Atención de SaludRESUMEN
OBJECTIVE: The study aimed to assess the prevalence of newly prescribed antipsychotic/benzodiazepine medication, as well as 30-day readmissions, among Hospital Elder Life Program (HELP)-enrolled patients. DESIGN: Retrospective case-control study. SETTING: HELP intervention took place in eight hospital units. The standard care group was selected from eight additional hospital units. PARTICIPANTS: Hospitalized patients, aged 65 years and older, enrolled in HELP during between January 1, 2017 to December 31, 2018 were included in the HELP cohort. Patients hospitalized in eight additional units during the same time frame were part of the standard care group. MEASUREMENTS: Antipsychotic/benzodiazepine medications were pulled from the electronic health record. History of chronic mental illnesses were classified by ICD10 codes. Basic descriptive statistics were used to analyze patient characteristics and comorbidities. Chi-squared and t-tests were performed to detect statistical differences as appropriate. RESULTS: There were 1411 patients in the HELP group and 10,807 patients in the standard care group. The HELP group was likely to be older, female and to have a shorten length of stay (all p ≤ 0.02). Our study demonstrated that approximately 8.9% (n = 125) of patients enrolled in HELP received an order for antipsychotics during their hospital admission, while 31.5% (n = 3400) from the standard care group (p < 0.001). The difference in benzodiazepine prescription in patients enrolled in HELP was also less when comparing the two groups (22.8% HELP vs 25.6% standard care; p = 0.02). CONCLUSIONS: Patients enrolled in the HELP group were less likely to receive a prescription for antipsychotics or benzodiazepines. The majority of patients enrolled in HELP were discharged to a more independent environment (home or assisted living) and there was a relatively low 30-day readmission rate among HELP patients.
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Antipsicóticos/uso terapéutico , Benzodiazepinas/uso terapéutico , Prescripciones de Medicamentos/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Readmisión del Paciente/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Registros Electrónicos de Salud , Femenino , Humanos , Clasificación Internacional de Enfermedades , Masculino , Prevalencia , Evaluación de Programas y Proyectos de Salud , Estudios RetrospectivosRESUMEN
We report the 1H T1 dispersion curve between 0 and 5 âMHz for the synthetic opioid fentanyl citrate (C28H36N2O8). The structures in the curve can be used to estimate the 14N nuclear quadrupole resonance (NQR) frequencies of the material. Density functional theory predictions of the NQR parameters of several fentanyl citrate compounds are also reported. The predictions for the aniline nitrogen are consistent with structures in the observed T1 data. To help interpret the fentanyl citrate results the T1 dispersion curve for the explosive ammonium nitrate is also presented.