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1.
Proc Natl Acad Sci U S A ; 121(1): e2303423120, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38150501

RESUMEN

The ability to efficiently control charge and spin in the cuprate high-temperature superconductors is crucial for fundamental research and underpins technological development. Here, we explore the tunability of magnetism, superconductivity, and crystal structure in the stripe phase of the cuprate La[Formula: see text]Ba[Formula: see text]CuO[Formula: see text], with [Formula: see text] = 0.115 and 0.135, by employing temperature-dependent (down to 400 mK) muon-spin rotation and AC susceptibility, as well as X-ray scattering experiments under compressive uniaxial stress in the CuO[Formula: see text] plane. A sixfold increase of the three-dimensional (3D) superconducting critical temperature [Formula: see text] and a full recovery of the 3D phase coherence is observed in both samples with the application of extremely low uniaxial stress of [Formula: see text]0.1 GPa. This finding demonstrates the removal of the well-known 1/8-anomaly of cuprates by uniaxial stress. On the other hand, the spin-stripe order temperature as well as the magnetic fraction at 400 mK show only a modest decrease under stress. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. However, strain produces an inhomogeneous suppression of the spin-stripe order at elevated temperatures. Namely, a substantial decrease of the magnetic volume fraction and a full suppression of the low-temperature tetragonal structure is found under stress, which is a necessary condition for the development of the 3D superconducting phase with optimal [Formula: see text]. Our results evidence a remarkable cooperation between the long-range static spin-stripe order and the underlying crystalline order with the three-dimensional fully coherent superconductivity. Overall, these results suggest that the stripe- and the SC order may have a common physical mechanism.

2.
Nature ; 574(7776): 72-75, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31548658

RESUMEN

Phases of matter are usually identified through spontaneous symmetry breaking, especially regarding unconventional superconductivity and the interactions from which it originates. In that context, the superconducting state of the quasi-two-dimensional and strongly correlated perovskite Sr2RuO4 is considered to be the only solid-state analogue to the superfluid 3He-A phase1,2, with an odd-parity order parameter that is unidirectional in spin space for all electron momenta and breaks time-reversal symmetry. This characterization was recently called into question by a search for an expected 'split' transition in a Sr2RuO4 crystal under in-plane uniaxial pressure, which failed to find any such evidence; instead, a dramatic rise and a peak in a single-transition temperature were observed3,4. Here we use nuclear magnetic resonance (NMR) spectroscopy of oxygen-17, which is directly sensitive to the order parameter via hyperfine coupling to the electronic spin degrees of freedom, to probe the nature of superconductivity in Sr2RuO4 and its evolution under strain. A reduction of the Knight shift is observed for all strain values and at temperatures below the critical temperature, consistent with a drop in spin polarization in the superconducting state. In unstrained samples, our results contradict a body of previous NMR work reporting no change in the Knight shift5 and the most prevalent theoretical interpretation of the order parameter as a chiral p-wave state. Sr2RuO4 is an extremely clean layered perovskite and its superconductivity emerges from a strongly correlated Fermi liquid, and our work imposes tight constraints on the order parameter symmetry of this archetypal system.

3.
J Intellect Disabil Res ; 68(9): 1036-1049, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38783394

RESUMEN

BACKGROUND: SYNGAP1- related intellectual disability (SYNGAP1-ID) is a rare genetic disorder presenting with intellectual disability (ID), epilepsy, maladaptive behaviours and communication challenges. To date, few studies have assessed the context in which these maladaptive behaviours occur. This study aims to investigate the prevalence of problem behaviours, characterise the behavioural phenotype and use well-validated measures to explore variables that maintain the behaviours. METHODS: Our sample includes 19 individuals diagnosed with SYNGAP1-ID and their parents. Parents provided information on behaviours that their children engage in, as well as their general behavioural dispositions. Well-validated measures (e.g., the Repetitive Behaviour Scale-Revised, Sensory Profile-2 and Vineland Adaptive Behaviour Scale) were used. A subset of individuals underwent further direct experimental assessment of their problem behaviour to identify the variables maintaining those problem behaviours. Parental reports were analysed using nonparametric statistical analysis; the direct assessments of individuals' problem behaviour were analysed using visual analysis and validated supplemental measures. RESULTS: All 19 individuals engaged in some form of maladaptive problem behaviour. Ratings of ritualistic, sameness and restricted behaviours measured by the RBS-R were commensurate with individuals diagnosed with idiopathic autism spectrum disorder (ASD) while self-injurious behaviours were endorsed at a higher level in SYNGAP1-ID when compared with idiopathic ASD. The problem behaviours in our cohort of patients with SYNGAP1-ID were maintained by automatic reinforcement and social attention and are positively correlated with atypical sensory responses. CONCLUSIONS: Individuals with SYNGAP1-ID engage in problem behaviours commensurate with other populations (e.g., those with ASD), they exhibit atypical response to sensory stimuli. Problem behaviours were frequently maintained by automatic reinforcement, which may result from a dysregulated sensory system. Children with SYNGAP1-ID may benefit from strategies used in persons with ASD.


Asunto(s)
Discapacidad Intelectual , Fenotipo , Proteínas Activadoras de ras GTPasa , Humanos , Discapacidad Intelectual/fisiopatología , Proteínas Activadoras de ras GTPasa/genética , Masculino , Femenino , Niño , Adolescente , Preescolar , Problema de Conducta , Adulto , Adulto Joven , Trastorno del Espectro Autista/fisiopatología
4.
J Surg Orthop Adv ; 32(3): 242-245, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38551232

RESUMEN

The purpose of this study was to evaluate the effectiveness of our novel chronic patellar tendon repair with allograft augmentation in an active-duty military population. From 2014 to 2018, five patients with chronic patellar tendon ruptures were treated with a primary repair of the patellar tendon augmented with Achilles tendon allograft. All patients were followed for 12 months, and their range of motion, Lysholm scores, and straight leg raise ability were assessed. Additionally, their return to active military duty was followed. All patients were managed with tendon reapproximation and Achilles allograft augmentation. Lysholm scores improved in all patients from an average of 35 to 87 postoperatively. No patients demonstrated postoperative extensor lag, and patients regained an average flexion of 130 degrees. All patients returned to active military duty. We presented a safe and effective technique to manage chronic patellar tendon ruptures that produced good outcomes. (Journal of Surgical Orthopaedic Advances 32(3):242-245, 2023).


Asunto(s)
Tendón Calcáneo , Traumatismos de la Rodilla , Ligamento Rotuliano , Traumatismos de los Tendones , Humanos , Ligamento Rotuliano/cirugía , Trasplante Homólogo , Traumatismos de los Tendones/cirugía , Traumatismos de la Rodilla/cirugía , Tendón Calcáneo/trasplante , Rotura/cirugía , Aloinjertos
5.
Phys Rev Lett ; 126(3): 037002, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33543973

RESUMEN

We report a comprehensive Cu L_{3}-edge resonant x-ray scattering (RXS) study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa_{2}Cu_{3}O_{6.67} under uniaxial compression up to 1% along the two inequivalent Cu─O─Cu bond directions (a and b) in the CuO_{2} planes. We confirm the strong in-plane anisotropy of the 2D charge correlations and observe their symmetric response to pressure: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic RXS measurements show that the 3D charge order resides exclusively in the CuO_{2} planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.

6.
Phys Rev Lett ; 125(9): 097005, 2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32915617

RESUMEN

We report muon spin rotation and magnetic susceptibility experiments on in-plane stress effects on the static spin-stripe order and superconductivity in the cuprate system La_{2-x}Ba_{x}CuO_{4} with x=0.115. An extremely low uniaxial stress of ∼0.1 GPa induces a substantial decrease in the magnetic volume fraction and a dramatic rise in the onset of 3D superconductivity, from ∼10 to 32 K; however, the onset of at-least-2D superconductivity is much less sensitive to stress. These results show not only that large-volume-fraction spin-stripe order is anticorrelated with 3D superconducting coherence but also that these states are energetically very finely balanced. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. These results strongly suggest a similar pairing mechanism for spin-stripe order and the spatially modulated 2D and uniform 3D superconducting orders, imposing an important constraint on theoretical models.

7.
BJOG ; 127(2): 239-249, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31454452

RESUMEN

BACKGROUND: The aetiology and pathogenesis of endometriosis are still under investigation. There is evidence that there is a complex bidirectional interaction between endometriosis and the microbiome. OBJECTIVE: To systematically review the available literature on the endometriosis-microbiome interaction, with the aim of guiding future inquiries in this emerging area of endometriosis research. SEARCH STRATEGY: MEDLINE, Embase, Scopus and Web of Science were searched through May 2019. A manual search of reference lists of relevant studies was also performed. SELECTION CRITERIA: Published and unpublished literature in any language describing a comparison of the microbiome state in mammalian hosts with and without endometriosis. DATA COLLECTION AND ANALYSIS: Identified studies were screened and assessed independently by two authors. Data were extracted and compiled in a qualitative synthesis of the evidence. MAIN RESULTS: Endometriosis appears to be associated with an increased presence of Proteobacteria, Enterobacteriaceae, Streptococcus spp. and Escherichia coli across various microbiome sites. The phylum Firmicutes and the genus Gardnerella also appear to have an association; however, this remains unclear. CONCLUSIONS: The complex bidirectional relationship between the microbiome and endometriosis has begun to be characterised by the studies highlighted in this systematic review. Laboratory and clinical studies demonstrate that there are indeed differences in the microbiome composition of hosts with and without endometriosis. TWEETABLE ABSTRACT: Review findings show endometriosis associated with increased Proteobacteria, Enterobacteriaceae, Streptococcus and Escherichia coli across various microbiome sites.


Asunto(s)
Endometriosis/microbiología , Microbioma Gastrointestinal/fisiología , Trastornos de la Menstruación/microbiología , Endometriosis/patología , Femenino , Humanos , Ciclo Menstrual/fisiología , Trastornos de la Menstruación/complicaciones , ARN Ribosómico 16S
8.
Phys Rev Lett ; 120(7): 076602, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29542933

RESUMEN

We report the results of a combined study of the normal-state resistivity and superconducting transition temperature T_{c} of the unconventional superconductor Sr_{2}RuO_{4} under uniaxial pressure. There is strong evidence that, as well as driving T_{c} through a maximum at ∼3.5 K, compressive strains ϵ of nearly 1% along the crystallographic [100] axis drive the γ Fermi surface sheet through a van Hove singularity, changing the temperature dependence of the resistivity from T^{2} above, and below the transition region to T^{1.5} within it. This occurs in extremely pure single-crystals in which the impurity contribution to the resistivity is <100 nΩ cm, so our study also highlights the potential of uniaxial pressure as a more general probe of this class of physics in clean systems.

9.
Phys Rev Lett ; 120(22): 225501, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29906167

RESUMEN

The Gardner transition is the transition that at mean-field level separates a stable glass phase from a marginally stable phase. This transition has similarities with the de Almeida-Thouless transition of spin glasses. We have studied a well-understood problem, that of disks moving in a narrow channel, which shows many features usually associated with the Gardner transition. We show that some of these features are artifacts that arise when a disk escapes its local cage during the quench to higher densities. There is evidence that the Gardner transition becomes an avoided transition, in that the correlation length becomes quite large, of order 15 particle diameters, even in our quasi-one-dimensional system.

10.
Br J Anaesth ; 119(5): 874-884, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29029012

RESUMEN

Heterogeneity among the primary studies included in a systematic review (SR) is one of the most challenging considerations for systematic reviewers. Current practices in anaesthesiology SRs have not been evaluated, but traditional methods may not provide sufficient information to evaluate the true nature of these differences. We address these issues by examining the practices for evaluating heterogeneity in anesthesiology reviews. Also, we propose a mapping method for presenting heterogeneous aspects of the primary studies in SRs.We evaluated heterogeneity practices reported in SRs published in highly ranked anesthesiology journals and Cochrane reviews. Elements extracted from the SRs included heterogeneity tests, models used, analyses conducted, plots used, and I2 values. Additionally, we selected a SR to develop an evidence map in order to display clinical heterogeneity.Our statistical analysis showed 150/207 SRs reporting a test for statistical heterogeneity. Plots were used in 138 reviews to display heterogeneity. Subgroup analyses were the most commonly reported analysis (54%). Meta-regression and sensitivity analyses were used sparingly (25%; 23% respectively). A random effects model was most commonly reported (33%). Heterogeneity statistics across meta-analyses suggested that, in our sample, the majority (55%) did not present sufficient heterogeneity to be of great concern. Cochrane reviews (n=58) were also analysed. Plots were used in 88% of Cochrane reviews. Subgroup analysis was used in 59% Cochrane reviews, while sensitivity analysis was used in 62%.Many reviews did not provide sufficient detail regarding heterogeneity. We are calling for improvement to reporting practices.


Asunto(s)
Anestesiología/métodos , Anestesiología/estadística & datos numéricos , Interpretación Estadística de Datos , Revisiones Sistemáticas como Asunto , Estudios Epidemiológicos , Humanos , Publicaciones Periódicas como Asunto , Proyectos de Investigación
11.
Gene Ther ; 23(10): 743-752, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27367841

RESUMEN

Pompe disease (glycogen storage disease type II (GSD-II)) is a myopathy caused by a genetic deficiency of acid α-glucosidase (GAA) leading to lysosomal glycogen accumulation causing muscle weakness, respiratory insufficiency and death. We previously demonstrated in GSD-II mice that a single injection of a helper-dependent adenovirus (HD-Ad) expressing GAA resulted in at least 300 days of liver secretion of GAA, correction of the glycogen storage in cardiac and skeletal muscles and improved muscle strength. Recent reports suggest that gene therapy modeling for lysososomal storage diseases in mice fails to predict outcomes in larger animal models. We therefore evaluated an HD-Ad expressing GAA in non-human primates. The baboons not only tolerated the procedure well, but the results also confirmed that a single dose of the HD-Ad allowed the livers of the treated animals to express and secrete large amounts of GAA for at least 6 months, at levels similar to those achieved in mice. Moreover, we detected liver-derived GAA in the heart, diaphragm and skeletal muscles of the treated animals for the duration of the study at levels that corrected glycogen accumulation in mice. This work validates our proof-of-concept studies in mice, and justifies future efforts using Ad-based vectors in Pompe disease patients.


Asunto(s)
Adenoviridae/genética , Terapia Genética/métodos , Enfermedad del Almacenamiento de Glucógeno Tipo II/terapia , Hígado/metabolismo , alfa-Glucosidasas/genética , Animales , Células Cultivadas , Diafragma/metabolismo , Terapia Genética/efectos adversos , Vectores Genéticos/efectos adversos , Vectores Genéticos/genética , Virus Helper/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Miocardio/metabolismo , Papio , alfa-Glucosidasas/metabolismo
12.
Am J Transplant ; 16(8): 2395-400, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26813253

RESUMEN

Contrast-induced nephropathy after endovascular aortic aneurysm repair (EVAR) in kidney transplant recipients (KTRs) can have devastating consequences. The Vascular Quality Initiative (VQI) database was queried to select all KTRs who underwent EVAR between January 2003 and December 2014. Our primary outcome was renal dysfunction, defined as acute kidney injury (AKI; elevation of serum creatinine >0.5 mg/dL from baseline) or new postoperative hemodialysis requirement. Within the EVAR VQI dataset, 40 patients were KTRs (40 of 17 213, or 0.2%). Renal dysfunction occurred in five of 40 patients in the KTR group in comparison to 779 of 17 173 patients in the nontransplanted group (12.5% versus 4.5%, p < 0.01). Emergent EVAR was required in 2 (5%) patients, one of whom required dialysis after surgery and subsequently died. One-year survival after EVAR was similar in the two groups (92.9% versus 93.1%, p = 0.73). KTRs who developed renal dysfunction had significantly lower preoperative estimated glomerular filtration rates (eGFRs) (29.5 versus 54.7, p = 0.007) and a significantly higher iodine:eGFR ratio (0.78 versus 0.39, p = 0.02) despite receiving a similar volume of contrast (70.0 versus 68.8, p = 0.97). Renal dysfunction is 3 times more frequent in KTRs treated with EVAR, though overall survival did not differ between the groups. Decreased preoperative eGFR and a higher iodine:eGFR ratio are associated with postoperative renal dysfunction.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Endovasculares/métodos , Fallo Renal Crónico/fisiopatología , Trasplante de Riñón , Insuficiencia Renal Crónica/epidemiología , Anciano , Aneurisma de la Aorta Abdominal/complicaciones , Boston/epidemiología , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Supervivencia de Injerto , Humanos , Incidencia , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/cirugía , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Receptores de Trasplantes
13.
Epidemiol Infect ; 143(10): 2131-6, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25518910

RESUMEN

As feral swine continue to expand their geographical range and distribution across the United States, their involvement in crop damage, livestock predation, and pathogen transmission is likely to increase. Despite the relatively recent discovery of feral swine involvement in the aetiology of a variety of pathogens, their propensity to transmit and carry a wide variety of pathogens is disconcerting. We examined sera from 2055 feral swine for antibody presence to six serovars of Leptospira that can also infect humans, livestock or domestic animals. About 13% of all samples tested positive for at least one serovar, suggesting that Leptospira infection is common in feral swine. Further studies to identify the proportion of actively infected animals are needed to more fully understand the risk they pose.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Leptospira/inmunología , Leptospirosis/veterinaria , Sus scrofa , Enfermedades de los Porcinos/epidemiología , Animales , Femenino , Leptospirosis/epidemiología , Masculino , Estudios Seroepidemiológicos , Porcinos , Estados Unidos/epidemiología
14.
J Am Acad Orthop Surg ; 32(17): 763-770, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38773841

RESUMEN

Pickleball is one of the fastest growing sports in the United States with millions of players nationwide. It is a relatively appealing sport because of its ease of access, low impact, and highly social atmosphere, allowing players of all ages to participate. As the number of players continues its dramatic increase, player injuries are certain to increase in turn. There is little to no orthopaedic research on pickleball-related injuries and a paucity of data regarding treatment and prevention strategies. This summary was designed to familiarize orthopaedic surgeons with the basics of the sport and highlight potential pickleball-related injuries they may encounter in practice.


Asunto(s)
Traumatismos en Atletas , Humanos , Traumatismos en Atletas/terapia , Deportes , Estados Unidos
15.
Nat Commun ; 15(1): 3277, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627407

RESUMEN

Uniaxial pressure provides an efficient approach to control charge density waves in YBa2Cu3Oy. It can enhance the correlation volume of ubiquitous short-range two-dimensional charge-density-wave correlations, and induces a long-range three-dimensional charge density wave, otherwise only accessible at large magnetic fields. Here, we use x-ray diffraction to study the strain dependence of these charge density waves and uncover direct evidence for a form of competition between them. We show that this interplay is qualitatively described by including strain effects in a nonlinear sigma model of competing superconducting and charge-density-wave orders. Our analysis suggests that strain stabilizes the 3D charge density wave in the regions between disorder-pinned domains of 2D charge density waves, and that the two orders compete at the boundaries of these domains. No signatures of discommensurations nor of pair density waves are observed. From a broader perspective, our results underscore the potential of strain tuning as a powerful tool for probing competing orders in quantum materials.

16.
HIV Med ; 14(7): 391-400, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23298380

RESUMEN

OBJECTIVES: The aim of the study was to compare the neuropsychiatric safety and tolerability of rilpivirine (TMC278) vs. efavirenz in a preplanned pooled analysis of data from the ECHO and THRIVE studies which compared the safety and efficacy of the two drugs in HIV-1 infected treatment naïve adults. METHODS: ECHO and THRIVE were randomized, double-blind, double-dummy, 96-week, international, phase 3 trials comparing the efficacy, safety and tolerability of rilpivirine 25 mg vs. efavirenz 600 mg once daily in combination with two background nucleoside/tide reverse transcriptase inhibitors. Safety and tolerability analyses were conducted when all patients had received at least 48 weeks of treatment or discontinued earlier. Differences between treatments in the incidence of neurological and psychiatric adverse events (AEs) of interest were assessed in preplanned statistical analyses using Fisher's exact test. RESULTS: At the time of the week 48 analysis, the cumulative incidences in the rilpivirine vs. efavirenz groups of any grade 2-4 treatment-related AEs and of discontinuation because of AEs were 16% vs. 31% (P<0.0001) and 3% vs. 8% (P=0.0005), respectively. The incidence of treatment-related neuropsychiatric AEs was 27% vs. 48%, respectively (P<0.0001). The incidence of treatment-related neurological AEs of interest was 17% vs. 38% (P<0.0001), and that of treatment-related psychiatric AEs of interest was 15% vs. 23% (P=0.0002). Dizziness and abnormal dreams/nightmares occurred significantly less frequently with rilpivirine vs. efavirenz (P<0.01). In both groups, patients with prior neuropsychiatric history tended to report more neuropsychiatric AEs but rates remained lower for rilpivirine than for efavirenz. CONCLUSIONS: Rilpivirine was associated with fewer neurological and psychiatric AEs of interest than efavirenz over 48 weeks in treatment-naïve, HIV-1-infected adults.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Benzoxazinas/efectos adversos , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Trastornos Mentales/inducido químicamente , Enfermedades del Sistema Nervioso/inducido químicamente , Nitrilos/efectos adversos , Pirimidinas/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alquinos , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Benzoxazinas/administración & dosificación , Benzoxazinas/uso terapéutico , Ciclopropanos , Infecciones por VIH/psicología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/fisiología , Humanos , Persona de Mediana Edad , Nitrilos/administración & dosificación , Nitrilos/uso terapéutico , Pirimidinas/administración & dosificación , Pirimidinas/uso terapéutico , Rilpivirina , Carga Viral/fisiología , Adulto Joven
17.
Colorectal Dis ; 15(8): 993-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23527537

RESUMEN

AIM: To determine the relationship between obstructed defaecation syndrome (ODS) and rectoceles. METHOD: From December 2007 to November 2011, all female patients with ODS were prospectively evaluated with full interview, clinical examination and anorectal physiology testing. The characteristics of patients with and without rectoceles were compared, and logistic regression was utilized to identify factors predictive of patients having a rectocele beyond the introitus. RESULTS: Of 239 patients with ODS, 90 (mean age: 52.3 ± 1.7 years) had a rectocele. Patients with rectoceles (R+) had a similar prevalence of incomplete emptying compared with patients with no rectocele (R-) (P ≥ 0.21), but only R+ patients reported splinting with defaecation (36.7% vs 0%; P < 0.0001). Anorectal manometry measurements, including mean resting pressure, maximum resting pressure and maximum squeeze pressure, were similar between groups (P ≥ 0.12). There were also no significant differences in rectal compliance (maximum tolerated volume) or rectal sensitivity (volume of first sensation) (P ≥ 0.65). R+ patients had greater difficulty expelling a 60 cm(3) balloon (70.1% R+ patients vs 57.5% R- patients; P = 0.05), but the prevalence of pelvic floor dyssynergia, as quantified by nonrelaxation on electromyography (EMG) testing, was similar to that of R- patients (P = 0.49). Logistic regression suggested that only difficulty with balloon expulsion was associated with higher odds of having a rectocele (OR = 3.00; P = 0.002), whereas mean resting pressure, EMG nonrelaxation and symptoms of incomplete emptying were not (P ≥ 0.12). CONCLUSION: Rectoceles are not associated with an increased severity of ODS-type symptoms, anorectal abnormalities or pelvic floor dyssynergia in patients with ODS. This suggests that rectoceles may be the result, rather than the cause, of ODS.


Asunto(s)
Canal Anal/fisiopatología , Estreñimiento/complicaciones , Defecación/fisiología , Diafragma Pélvico/fisiopatología , Rectocele/complicaciones , Recto/fisiopatología , Vagina/fisiopatología , Adulto , Anciano , Ataxia/diagnóstico , Estudios de Cohortes , Estreñimiento/fisiopatología , Electromiografía , Femenino , Humanos , Modelos Logísticos , Manometría/métodos , Persona de Mediana Edad , Estudios Prospectivos , Rectocele/fisiopatología , Recto/anatomía & histología
18.
Science ; 382(6669): 447-450, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37883549

RESUMEN

The interplay of electronic and structural degrees of freedom in solids is a topic of intense research. More than 60 years ago, Lifshitz discussed a counterintuitive possibility: lattice softening driven by conduction electrons at topological Fermi surface transitions. The effect that he predicted, however, was small and has not been convincingly observed. Using a piezo-based uniaxial pressure cell to tune the ultraclean metal strontium ruthenate while measuring the stress-strain relationship, we reveal a huge softening of the Young's modulus at a Lifshitz transition of a two-dimensional Fermi surface and show that it is indeed driven entirely by the conduction electrons of the relevant energy band.

19.
Ann Hematol ; 91(11): 1795-801, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22836946

RESUMEN

Generally, patients' actual body weight (ABW) is used to calculate the number of CD34⁺ cells to be harvested for autologous haematopoietic progenitor cell (HPC) transplantation. In our institution, 'overweight' patients weighing at least 25% more than their ideal body weight (IBW) have their adjusted ideal body weight (AdjIBW) used for determination of blood volume to be processed to achieve a minimum target of CD34⁺ cells per kilogram, as well as CD34⁺ cell dosage calculation at transplant. AdjIBW is calculated as follows: AdjIBW = IBW + 0.25 × (actual weight - IBW). We have used AdjIBW for 65/153 patients who have had autologous HPC harvests, with a median AdjIBW of 69 kg (range, 50-110 kg). Median actual weight was 90 kg (range, 62-175 kg). Median volume of peripheral blood processed to achieve a minimum 2 × 106 CD34⁺ cells/kg for these patients was 13.2 L (range, 5-35 L), and the median CD34⁺ cells × 106/kg collected for AdjIBW was 6.3 (range, 1.7-33). For normal-weight patients (n = 88; median ABW, 75 kg; range, 49-98 kg), the corresponding median apheresis volume was 16 L (range, 7-24 L), and median CD34⁺ cells × 106/kg harvested was 4.5 (range, 1.4-15.9). In total, 35 in a total transplant cohort of 82 patients had AdjIBW used to determine CD34⁺ cell dose at time of transplant, with a median of 4.5 × 106/kg, (if their ABW was used in the calculation; 3.1 × 106/kg), compared to median dose of 3.2 × 106/kg ABW for the normal-weight patient cohort. All patients engrafted with no significant difference between median times to neutrophil and platelet engraftment for the overweight (13 and 15 days, respectively) compared with normal-weight (12 and 14 days, respectively) patient cohorts. We conclude that the use of AdjIBW is a useful tool for successful harvest and subsequent transplant for overweight patients, with no adverse effect on engraftment times.


Asunto(s)
Volumen Sanguíneo , Neoplasias Hematológicas/terapia , Movilización de Célula Madre Hematopoyética , Trasplante de Células Madre Hematopoyéticas , Peso Corporal Ideal , Sobrepeso/complicaciones , Algoritmos , Antígenos CD34 , Peso Corporal , Estudios de Cohortes , Femenino , Supervivencia de Injerto , Neoplasias Hematológicas/sangre , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/metabolismo , Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/metabolismo , Humanos , Recuento de Leucocitos , Masculino , Neutrófilos/patología , Obesidad/complicaciones , Recuento de Plaquetas , Trasplante Autólogo
20.
Anesth Prog ; 59(1): 3-11, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22428968

RESUMEN

This study describes what training programs in pediatric dentistry and dental anesthesiology are doing to meet future needs for deep sedation/general anesthesia services required for pediatric dentistry. Residency directors from 10 dental anesthesiology training programs in North America and 79 directors from pediatric dentistry training programs in North America were asked to answer an 18-item and 22-item online survey, respectively, through an online survey tool. The response rate for the 10 anesthesiology training program directors was 9 of 10 or 90%. The response rate for the 79 pediatric dentistry training program directors was 46 of 79 or 58%. Thirty-seven percent of pediatric dentistry programs use clinic-based deep sedation/general anesthesia for dental treatment in addition to hospital-based deep sedation/general anesthesia. Eighty-eight percent of those programs use dentist anesthesiologists for administration of deep sedation/general anesthesia in a clinic-based setting. Pediatric dentistry residency directors perceive a future change in the need for deep sedation/general anesthesia services provided by dentist anesthesiologists to pediatric dentists: 64% anticipate an increase in need for dentist anesthesiologist services, while 36% anticipate no change. Dental anesthesiology directors compared to 2, 5, and 10 years ago have seen an increase in the requests for dentist anesthesiologist services by pediatric dentists reported by 56% of respondents (past 2 years), 63% of respondents (past 5 years), and 88% of respondents (past 10 years), respectively. Predicting the future need of dentist anesthesiologists is an uncertain task, but these results show pediatric dentistry directors and dental anesthesiology directors are considering the need, and they recognize a trend of increased need for dentist anesthesiologist services over the past decade.


Asunto(s)
Anestesia Dental/estadística & datos numéricos , Anestesia General/estadística & datos numéricos , Anestesiología/estadística & datos numéricos , Sedación Profunda/estadística & datos numéricos , Odontólogos/estadística & datos numéricos , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Internado y Residencia/estadística & datos numéricos , Odontología Pediátrica/estadística & datos numéricos , Anestesiología/educación , Niño , Clínicas Odontológicas/estadística & datos numéricos , Servicio Odontológico Hospitalario/estadística & datos numéricos , Educación de Posgrado en Odontología/estadística & datos numéricos , Predicción , Necesidades y Demandas de Servicios de Salud/tendencias , Humanos , Evaluación de Necesidades/estadística & datos numéricos , Evaluación de Necesidades/tendencias , América del Norte , Odontología Pediátrica/educación , Encuestas y Cuestionarios
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