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1.
Small ; 20(40): e2401558, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38829043

RESUMEN

By primarily adjusting the reagent amounts, particularly the volume of AgNO3 solution introduced, Ag2O cubes with decreasing sizes from 440 to 79 nm, octahedra from 714 to 106 nm, and rhombic dodecahedra from 644 to 168 nm are synthesized. 733 nm cuboctahedra are also prepared for structural analysis. With in-house X-ray diffraction (XRD) peak calibration, shape-related peak shifts are recognizable. Synchrotron XRD measurements at 100 K reveal the presence of bulk and surface layer lattices. Bulk cell constants also deviate slightly. They show a negative thermal expansion behavior with shrinking cell constants at higher temperatures. The Ag2O crystals exhibit size- and facet-dependent optical properties. Bandgaps red-shift continuously with increasing particle sizes. Optical facet effect is also observable. Moreover, synchrotron XRD peaks of a mixture of Cu2O rhombicuboctahedra and edge- and corner-truncated cubes exposing all three crystal faces can be deconvoluted into three components with the bulk and the [111] microstrain phase as the major component. Interestingly, while the unheated Cu2O sample shows clear diffraction peak asymmetry, annealing the sample to 450 K yields nearly symmetric peaks even when returning the sample to room temperature, meaning even moderately high temperatures can permanently change the crystal lattice.

2.
J Community Health ; 49(3): 458-465, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38095814

RESUMEN

Rural populations experience a number of disparities that place them at increased risk of morbidity and mortality related to chronic disease, including lower health literacy and greater distance to medical care. Community-based free healthcare education can offer targeted preventive care to these vulnerable populations; however, limited quantitative research exists measuring their impact, specifically on health literacy and likelihood for behavior change. To investigate this, a student-led health education clinic was held in January 2023 in the rural community of Lykens, Pennsylvania by the Student-run and Collaborative Outreach Program for Health Equity (SCOPE). Fifty-five pre- and post-clinic surveys using Likert-style questions measured the knowledge and likelihood of behavioral change for several preventive health topics, including hypertension, diabetes mellitus, cancer screenings, childhood vaccinations, skin cancer, mental health, addiction, and nutrition. From pre- to post-clinic, there was a significant increase in knowledge of hypertension (p = 0.023) and diabetes (p = 0.014), likelihood of attending cancer screenings (p = 0.038), and confidence in identifying cancerous moles (p = < 0.001). There was a non-significant increase in understanding of mental health and nutrition, and no change in understanding of addiction or childhood vaccinations. It is likely that the level of interaction in education provided and relevance of information to participants contributed to effective uptake of information. The results demonstrate an immediate impact on health literacy and likelihood of behavioral change for several important preventive health topics, and advocate for the use of student-run healthcare interventions in addressing the prevalence of chronic disease in rural communities.


Asunto(s)
Alfabetización en Salud , Hipertensión , Neoplasias , Humanos , Población Rural , Pennsylvania , Alfabetización en Salud/métodos , Educación en Salud , Enfermedad Crónica , Estudiantes
3.
Small ; 19(9): e2205920, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36521932

RESUMEN

BaTiO3 octahedra, edge-, and corner-truncated cubes, and cubes with four tunable sizes from 132 to 438 nm are synthesized by a solvothermal growth approach. Acetic acid treatment can cleanly remove BaCO3 impurity. Rietveld refinement of X-ray diffraction patterns and Raman spectra help to confirm the particles have a tetragonal crystal structure. The crystals also exhibit size- and facet-dependent bandgap shifts. BaTiO3 octahedra show larger piezoelectric, ferroelectric, and pyroelectric effects than truncated cubes and cubes. The measured dielectric constant differences should be associated with their various facet-dependent behaviors. Piezoelectric nanogenerators fabricated from BaTiO3 octahedra consistently show the best performance than those containing truncated cubes and cubes. In particular, a nanogenerator with 30 wt.%-incorporated octahedra displays an open-circuit voltage of 23 V and short-circuit current of 324 nA. The device performance is also highly stable. The maximum output power reaches 3.9 µW at 60 MΩ. The fabricated nanogenerator can provide sufficient electricity to power light-emitting diodes. This work further demonstrates that various physical properties of semiconductor crystals show surface dependence.

4.
Small ; 19(44): e2303491, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37381620

RESUMEN

Semiconductor crystals have generally shown facet-dependent electrical, photocatalytic, and optical properties. These phenomena have been proposed to result from the presence of a surface layer with bond-level deviations. To provide experimental evidence of this structural feature, synchrotron X-ray sources are used to obtain X-ray diffraction (XRD) patterns of polyhedral cuprous oxide crystals. Cu2 O rhombic dodecahedra display two distinct cell constants from peak splitting. Peak disappearance during slow Cu2 O reduction to Cu with ammonia borane differentiates bulk and surface layer lattices. Cubes and octahedra also show two peak components, while diffraction peaks of cuboctahedra are comprised of three components. Temperature-varying lattice changes in the bulk and surface regions also show shape dependence. From transmission electron microscopy (TEM) images, slight plane spacing deviations in surface and inner crystal regions are measured. Image processing provides visualization of the surface layer with depths of about 1.5-4 nm giving dashed lattice points instead of dots from atomic position deviations. Close TEM examination reveals considerable variation in lattice spot size and shape for different particle morphologies, explaining why facet-dependent properties are emerged. Raman spectrum reflects the large bulk and surface lattice difference in rhombic dodecahedra. Surface lattice difference can change the particle bandgap.

5.
Langmuir ; 38(8): 2729-2736, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35172578

RESUMEN

CdSe nanocrystals with average sizes of 15, 24, and 32 nm have been synthesized from an aqueous solution of Na2SeSO3, HCl, and cadmium nitrate at 15, 45, and 70 °C, respectively, for about 1 h. Mixing aqueous CdCl2, HNO3, and Na2SeSO3 at 22 °C for 4 h yields 44 nm CdSe nanocrystals. X-ray and electron diffraction analyses indicate the possession of a zinc blende crystal structure for all the samples. Despite the large particle dimensions, their absorption band red-shifts significantly from 520 to 570 nm with increasing particle sizes, and band gap values decrease from 2.03 eV for 15 nm particles to 1.68 eV for 44 nm crystals. Although these nanocrystals are not emissive, introduction of the cetyltrimethylammonium chloride surfactant during crystal growth can restore their photoluminescence attributed to the improved crystal quality, and the similarly sized CdSe nanocrystals have an emission band red-shifting from 544 nm for 15 nm particles to 583 nm for 47 nm crystals. A band diagram was constructed for these CdSe nanocrystals using information from Mott-Schottky plots. While they have close conduction band positions, the notable size-related band gap variation means that their valence band energies differ considerably with implications of electrochemical and photocatalytic properties. The 44 nm CdSe particles also show the smallest electrochemical charge-transfer resistance.

6.
Phys Chem Chem Phys ; 24(45): 28081, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36367452

RESUMEN

Expression of concern for 'Surface-dependent band structure variations and bond deviations of GaN' by Chih-Shan Tan et al., Phys. Chem. Chem. Phys., 2022, 24, 9135-9140, https://doi.org/10.1039/D2CP00100D.

7.
Phys Chem Chem Phys ; 24(16): 9135-9140, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35403651

RESUMEN

Density functional theory (DFT) calculations on a tunable number of GaN (0001) planes give an invariant band structure, density of states (DOS) diagram, and band gap of the GaN unit cell. Dissimilar band structures and DOS diagrams are obtained for 1, 3, 5, 7, and 9 layers of GaN (101̄0) planes, but the same band structure as that of the (0001) plane returns for 2, 4, 6, and 8 (101̄0) planes. Furthermore, 1 to 4 layers of GaN (101̄1) planes exhibit dissimilar band structures, but the GaN unit cell band structure is obtained for 5 (101̄1) planes. While there are no changes to the Ga-N bond length and bond geometry for the (0001) planes, the (101̄0) planes present bond length variation and bond distortion with odd numbers of layers. Bond length and bond direction deviations are also obtained for 1 to 4 (101̄1) planes. These results suggest that slight structural deviations may be present near the GaN surface to produce facet-dependent properties, and such atomic position deviations in the surface layer can be observed in various semiconductors.

8.
Cochrane Database Syst Rev ; 7: CD013100, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35844143

RESUMEN

BACKGROUND: Whilst antipsychotics are the mainstay of treatment for schizophrenia spectrum disorders, there have been numerous attempts to identify biomarkers that can predict treatment response. One potential marker may be psychomotor abnormalities, including catatonic symptoms. Early studies suggested that catatonic symptoms predict poor treatment response, whilst anecdotal reports of rare adverse events have been invoked against antipsychotics. The efficacy and safety of antipsychotics in the treatment of this subtype of schizophrenia have rarely been studied in randomised controlled trials (RCTs). OBJECTIVES: To compare the effects of any single antipsychotic medication with another antipsychotic or with other pharmacological agents, electroconvulsive therapy (ECT), other non-pharmacological neuromodulation therapies (e.g. transcranial magnetic stimulation), or placebo for treating positive, negative, and catatonic symptoms in people who have schizophrenia spectrum disorders with catatonic symptoms. SEARCH METHODS: We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials, which is based on CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, PubMed, ClinicalTrials.gov, the ISRCTN registry, and WHO ICTRP, on 19 September 2021. There were no language, date, document type, or publication status limitations for inclusion of records in the register. We also manually searched reference lists from the included studies, and contacted study authors when relevant. SELECTION CRITERIA: All RCTs comparing any single antipsychotic medication with another antipsychotic or with other pharmacological agents, ECT, other non-pharmacological neuromodulation therapies, or placebo for people who have schizophrenia spectrum disorders with catatonic symptoms. DATA COLLECTION AND ANALYSIS: two review authors independently inspected citations, selected studies, extracted data, and appraised study quality. For binary outcomes, we planned to calculate risk ratios and their 95% confidence intervals (CI) on an intention-to-treat basis. For continuous outcomes, we planned to calculate mean differences between groups and their 95% CI. We assessed risk of bias for the included studies, and created a summary of findings table; however, we did not assess the certainty of the evidence using the GRADE approach because there was no quantitative evidence in the included study. MAIN RESULTS: Out of 53 identified reports, one RCT including 14 hospitalised adults with schizophrenia and catatonic symptoms met the inclusion criteria of the review. The study, which was conducted in India and lasted only three weeks, compared risperidone with ECT in people who did not respond to an initial lorazepam trial.   There were no usable data reported on the primary efficacy outcomes of clinically important changes in positive, negative, or catatonic symptoms. Whilst both study groups improved in catatonia scores on the Bush-Francis Catatonia Rating Scale (BFCRS), the ECT group showed significantly greater improvement at week 3 endpoint (mean +/- estimated standard deviation; 0.68 +/- 4.58; N = 8) than the risperidone group (6.04 +/- 4.58; N = 6; P = 0.035 of a two-way analysis of variance (ANOVA) for repeated measures originally conducted in the trial). Similarly, both groups improved on the Positive and Negative Syndrome Scale (PANSS) scores by week 3, but ECT showed significantly greater improvement in positive symptoms scores compared with risperidone (P = 0.04). However, data on BFCRS scores in the ECT group appeared to be skewed, and mean PANSS scores were not reported, thereby precluding further analyses of both BFCRS and PANSS data according to the protocol.  Although no cases of neuroleptic malignant syndrome were reported, extrapyramidal symptoms as a primary safety outcome were reported in three cases in the risperidone group. Conversely, headache (N = 6), memory loss (N = 4), and a prolonged seizure were reported in people receiving ECT. These adverse effects, which were assessed as specific for antipsychotics and ECT, respectively, were the only adverse effects reported in the study. However, the exact number of participants with adverse events was not clearly reported in both groups, precluding further analysis.  Our results were based only on a single study with a very small sample size, short duration of treatment, unclear or high risk of bias due to unclear randomisation methods, possible imbalance in baseline characteristics, skewed data, and selective reporting. Data on outcomes of general functioning, global state, quality of life, and service use, as well as data on specific phenomenology and duration of catatonic symptoms, were not reported. AUTHORS' CONCLUSIONS: We found only one small, short-term trial suggesting that risperidone may improve catatonic and positive symptoms scale scores amongst people with schizophrenia spectrum disorders and catatonic symptoms, but that ECT may result in greater improvement in the first three weeks of treatment. Due to small sample size, methodological shortcomings and brief duration of the study, as well as risk of bias, the evidence from this review is of very low quality. We are uncertain if these are true effects, limiting any conclusions that can be drawn from the evidence. No cases of neuroleptic malignant syndrome were reported, but we cannot rule out the risk of this or other rare adverse events in larger population samples.  High-quality trials continue to be necessary to differentiate treatments for people with symptoms of catatonia in schizophrenia spectrum disorders. The lack of consensus on the psychopathology of catatonia remains a barrier to defining treatments for people with schizophrenia. Better understanding of the efficacy and safety of antipsychotics may clarify treatment for this unique subtype of schizophrenia.


ANTECEDENTES: Aunque los antipsicóticos son la base del tratamiento de los trastornos del espectro de la esquizofrenia, ha habido numerosos intentos de identificar biomarcadores que puedan predecir la respuesta al tratamiento. Un posible marcador podrían ser las anomalías psicomotoras, incluidos los síntomas catatónicos. Los estudios más antiguos indican que los síntomas catatónicos predicen una respuesta deficiente al tratamiento, mientras que se han alegado informes anecdóticos de eventos adversos poco frecuentes contra los antipsicóticos. La eficacia y la seguridad de los antipsicóticos en el tratamiento de este subtipo de esquizofrenia rara vez se han estudiado en ensayos controlados aleatorizados (ECA). OBJETIVOS: Comparar los efectos de cualquier fármaco antipsicótico único con otro antipsicótico o con otros agentes farmacológicos, terapia electroconvulsiva (TEC), otras terapias de neuromodulación no farmacológicas (p. ej., estimulación magnética transcraneal) o placebo para el tratamiento de los síntomas positivos, negativos y catatónicos en personas que presentan trastornos del espectro de la esquizofrenia con síntomas catatónicos. MÉTODOS DE BÚSQUEDA: El 19 de septiembre de 2021 se realizaron búsquedas en el registro de ensayos basados en estudios del Grupo Cochrane de Esquizofrenia (Cochrane Schizophrenia Group), que se basa en CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, PubMed, ClinicalTrials.gov, el registro ISRCTN y la ICTRP de la OMS. No hubo limitaciones de idioma, fecha, tipo de documento o estado de publicación para la inclusión de los registros en el registro. También se realizaron búsquedas manuales en las listas de referencias de los estudios incluidos y se estableció contacto con los autores de los estudios cuando fue pertinente. CRITERIOS DE SELECCIÓN: Todos los ECA que compararan cualquier fármaco antipsicótico único con otro antipsicótico o con otros agentes farmacológicos, TEC, otras terapias de neuromodulación no farmacológicas o placebo en personas que presentan trastornos del espectro de la esquizofrenia con síntomas catatónicos. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Dos autores de la revisión inspeccionaron de forma independiente las citas, seleccionaron los estudios, extrajeron los datos y evaluaron la calidad de los estudios. Para los desenlaces binarios se planeó calcular las razones de riesgos y sus intervalos de confianza (IC) del 95% sobre la base de la intención de tratar. Para los desenlaces continuos se planeó calcular las diferencias de medias entre los grupos y sus IC del 95%. Se evaluó el riesgo de sesgo de los estudios incluidos y se creó una tabla de resumen de los hallazgos. Sin embargo, no se evaluó la certeza de la evidencia mediante el método GRADE porque no hubo evidencia cuantitativa en el estudio incluido. RESULTADOS PRINCIPALES: De los 53 informes identificados, un ECA que incluyó a 14 adultos hospitalizados con esquizofrenia y síntomas catatónicos cumplió con los criterios de inclusión de la revisión. El estudio, realizado en la India y que sólo duró tres semanas, comparó la risperidona con la TEC en personas que no respondieron a una prueba inicial con lorazepam. No se informaron datos utilizables sobre los desenlaces principales de eficacia de cambios clínicamente importantes en los síntomas positivos, negativos o catatónicos. Aunque ambos grupos del estudio mejoraron en las puntuaciones de catatonia en la Bush­Francis Catatonia Rating Scale (BFCRS), el grupo de TEC mostró una mejoría significativamente mayor en el desenlace a las tres semanas (media +/­ desviación estándar estimada; 0,68 +/­ 4,58; n = 8) que el grupo de risperidona (6,04 +/­ 4,58; n = 6; p = 0,035 de un análisis de varianza (ANOVA) de dos vías para medidas repetidas realizado originalmente en el ensayo). Asimismo, ambos grupos mejoraron en las puntuaciones de la Positive and Negative Syndrome Scale (PANSS) a las tres semanas, pero la TEC mostró una mejoría significativamente mayor en las puntuaciones de los síntomas positivos en comparación con la risperidona (p = 0,04). Sin embargo, los datos sobre las puntuaciones de la BFCRS en el grupo de TEC parecieron estar sesgados, y no se informaron las puntuaciones medias de la PANSS, lo que impidió realizar más análisis de los datos de la BFCRS y la PANSS según el protocolo. Aunque no se informaron casos de síndrome neuroléptico maligno, en tres casos del grupo de risperidona se notificaron síntomas extrapiramidales como un desenlace principal de seguridad. Por el contrario, en las personas que recibieron TEC se informó cefalea (n = 6), pérdida de memoria (n = 4) y una convulsión prolongada. Estos efectos adversos, que se evaluaron como específicos de los antipsicóticos y de la TEC, respectivamente, fueron los únicos efectos adversos notificados en el estudio. Sin embargo, el número exacto de participantes con eventos adversos no se informó claramente en ambos grupos, lo que impidió realizar un análisis más profundo. Los resultados de esta revisión se basaron en un solo estudio con un tamaño muestral muy pequeño, una duración corta del tratamiento, un riesgo de sesgo incierto o alto debido a métodos de asignación al azar poco claros, un posible desequilibrio en las características iniciales, datos sesgados y un informe selectivo. No se informaron datos sobre los desenlaces de funcionalidad general, estado global, calidad de vida ni uso de los servicios, así como tampoco datos sobre la fenomenología específica ni la duración de los síntomas catatónicos. CONCLUSIONES DE LOS AUTORES: Solo se encontró un ensayo pequeño, a corto plazo, que indica que la risperidona podría mejorar las puntuaciones de la escala de síntomas catatónicos y positivos entre las personas con trastornos del espectro de la esquizofrenia y síntomas catatónicos, pero que la TEC podría producir una mayor mejoría en las primeras tres semanas de tratamiento. Debido al pequeño tamaño muestral, las deficiencias metodológicas y la breve duración del estudio, así como el riesgo de sesgo, la evidencia de esta revisión es de calidad muy baja. No hay confianza en que estos efectos sean verdaderos, lo que limita cualquier conclusión que se pueda sacar a partir de la evidencia. No se notificaron casos de síndrome neuroléptico maligno, pero no se puede descartar el riesgo de este u otros eventos adversos poco frecuentes en muestras poblacionales más grandes. Aún se necesitan ensayos de calidad alta para diferenciar los tratamientos en las personas con síntomas de catatonia en los trastornos del espectro de la esquizofrenia. La falta de consenso sobre la psicopatología de la catatonia todavía es un obstáculo para definir los tratamientos para las personas con esquizofrenia. Un mejor conocimiento de la eficacia y la seguridad de los antipsicóticos podría aclarar el tratamiento de este subtipo único de esquizofrenia.


Asunto(s)
Antipsicóticos , Catatonia , Síndrome Neuroléptico Maligno , Esquizofrenia , Adulto , Antipsicóticos/efectos adversos , Catatonia/tratamiento farmacológico , Humanos , Síndrome Neuroléptico Maligno/tratamiento farmacológico , Risperidona/uso terapéutico , Esquizofrenia/complicaciones , Esquizofrenia/tratamiento farmacológico
9.
BMC Nephrol ; 23(1): 97, 2022 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-35247959

RESUMEN

BACKGROUND: Long-term kidney transplant survival at the population level is consistently favorable, but this survival varies widely at an individual level due to both recipient and donor factors. The distinct contribution of recipient and donor factors to individual post kidney transplant outcome remains unclear. Comparing outcomes in deceased donor (DD) recipients with potential but non-actualized living donors (DD1) to those recipients with actualized living donors (LD), and to DD recipients without potential living donors (DD0) may provide transplant candidates with more information about their own post-transplant prognosis. METHODS: We conducted an observational retrospective cohort study of kidney transplant candidates presenting to our centre for evaluation between 01/01/06 and 31/12/18, and who also received a transplant during that time. Patients were followed to 31/08/2019. Candidates were classified as DD0, DD1, or LD based on whether they had an identified living donor at the time of initial pre-transplant assessment, and if the donor actualized or not. Primary outcome was 5-year death-censored graft survival, adjusted for common pre- and post-transplant donor and recipient risk factors. Secondary outcomes analyzed included patient survival and graft function. RESULTS: There were 453 kidney transplant recipients (LD = 136, DD1 = 83, DD0 = 234) who received a transplant during the study period. DD0 and DD1 did not differ in key donor organ characteristics. The 5-year death censored graft survival of DD1 was similar to LD (p = 0.19). DD0 graft survival was inferior to LD (p = 0.005), but also trended inferior to DD1 (p = 0.052). By multivariate Cox regression analysis, LD demonstrated similar 5-year graft survival to DD1 (HR for graft loss 0.8 [95% CI 0.25-2.6], p = 0.72) but LD graft survival was superior to DD0 (HR 0.34 [0.16-0.72], p = 0.005). The 5-year patient survival in DD1 was similar to LD (p = 0.26) but was superior to DD0 (p = 0.01). CONCLUSIONS: DD recipients with potential but non-actualized living donors exhibit similar mid-term graft and patient survival compared to LD recipients. Having an identified living donor at the time of pre-transplant assessment portends a favorable prognosis for the recipient.


Asunto(s)
Supervivencia de Injerto , Donadores Vivos , Humanos , Riñón , Estudios Retrospectivos , Donantes de Tejidos , Resultado del Tratamiento
10.
Cardiol Young ; : 1-3, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36348618

RESUMEN

Bicuspid aortic valve is the most common congenital heart malformation and predisposes patients to thoracic aortic aneurysms and aortic dissections. Current peripartum guidelines are extrapolated from other heritable causes of thoracic aortic disease and do not account for unique characteristics of bicuspid aortic valve patients. We therefore evaluated the prevalence of maternal and fetal complications of women with early-onset complications of bicuspid aortic valve disease in the UTHealth Bicuspid Aortic Valve Research Registry. We found that the rate of cardiovascular complications was high and that relatively few women received guideline-recommended care.

11.
Knee Surg Sports Traumatol Arthrosc ; 30(3): 1095-1108, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34165631

RESUMEN

PURPOSE: Femoroacetabular impingement (FAI) is a hip disorder which can often present bilaterally. The purpose of this systematic review was to explore the current practices for bilateral hip arthroscopy in treating FAI as they relate to outcomes and complications. METHODS: This review has been conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). The electronic databases PubMed, MEDLINE, EMBASE, and CENTRAL (Cochrane Central Register of Controlled Trials) were searched from data inception to October 18th, 2020. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. Data are presented descriptively. RESULTS: Overall, 19 studies were identified, comprising 957 patients (48.6% male) with a mean age of 27.9 ± 7.1 years and a mean follow-up of 31.7 ± 20.8 months. The majority of patients were treated with a staged bilateral hip arthroscopy (78.5%) with a mean duration between surgeries of 7.1 ± 4.0 months. Significant preoperative-to-postoperative improvements for clinical outcomes such as pain, hip function, and health-related daily living as well as radiographic outcomes were reported in six studies for staged procedures (p < 0.05) and three studies for simultaneous procedures (p < 0.02). Significant improvements in patient-reported outcomes (e.g., HOS-ADL, Pain, HOS-SS, mHHS, and NAHS) were found in favor of those undergoing a shorter delay between surgeries in three studies (i.e., < 3, 10 or 17 months) (p < 0.05) compared to those who had delayed surgeries (i.e., > 3, 10, or 17 months). The overall complication rate was 10.1% (97/957). CONCLUSIONS: Bilateral surgery for FAI yields improved outcomes postoperatively and complication rates similar to unilateral surgery. The overall complication rate was 10.1% with the most common complication being revision surgery. Staged bilateral surgery is more commonly performed than simultaneous surgery. Clinicians should consider preoperative imaging, clinical history, and patient values when deciding between staged and simultaneous procedures for bilateral FAI surgery. Future studies are required to determine the optimal indications for simultaneous versus staged procedures, as well as the ideal timing between surgeries for the latter. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Artroscopía , Pinzamiento Femoroacetabular , Articulación de la Cadera , Actividades Cotidianas , Artroscopía/métodos , Pinzamiento Femoroacetabular/cirugía , Articulación de la Cadera/cirugía , Humanos , Resultado del Tratamiento
12.
J Am Chem Soc ; 143(13): 4969-4978, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33764051

RESUMEN

Two-dimensional-on-three-dimensional (2D/3D) halide perovskite heterostructures have been extensively utilized in optoelectronic devices. However, the labile nature of halide perovskites makes it difficult to form such heterostructures with well-defined compositions, orientations, and interfaces, which inhibits understanding of the carrier transfer properties across these heterostructures. Here, we report solution growth of both horizontally and vertically aligned 2D perovskite (PEA)2PbBr4 (PEA = phenylethylammonium) microplates onto 3D CsPbBr3 single crystal thin films, with well-defined heterojunctions. Time-resolved photoluminescence (TRPL) transients of the heterostructures exhibit the monomolecular and bimolecular dynamics expected from exciton annihilation, dissociation, and recombination, as well as evidence for carrier transfer in these heterostructures. Two kinetic models based on Type-I and Type-II band alignments at the interface of horizontal 2D/3D heterostructures are applied to reveal a shift in balance between carrier transfer and recombination: Type-I band alignment better describes the behaviors of heterostructures with thin 2D perovskite microplates but Type-II band alignment better describes those with thick 2D microplates (>150 nm). TRPL of vertically aligned 2D microplates is dominated by directly excited PL and is independent of the height above the 3D film. Electrical measurements reveal current rectification behaviors in both heterostructures with vertical heterostructures showing better electrical transport. As the first systematic study on comparing models of 2D/3D perovskite heterostructures with controlled orientations and compositions, this work provides insights on the charge transfer mechanisms in these perovskite heterostructures and guidelines for designing better optoelectronic devices.

13.
J Pediatr Hematol Oncol ; 43(1): e141-e145, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33235141

RESUMEN

Pediatric low-grade gliomas (LGGs) are the most common brain tumors in children. Treatment of pediatric LGG can often be challenging, particularly when not resectable and refractory or recurrent following standard chemotherapy regimens. There is no current accepted standard of care salvage regimen for progressive LGG after the failure of first-line chemotherapy. A web-based survey was distributed to pediatric cancer centers throughout North America to inquire regarding institutional preferences of salvage treatment strategies after initial chemotherapy for LGG in children less than 10 years of age, as well as molecular testing preferences. Highlights from the survey results were as follows: vincristine/carboplatin (VC) and vinblastine (VBL) were the top 2 preferred salvage regimens for non-BRAF-altered pediatric LGG. BRAF and MEK inhibitors were the most preferred salvage regimens for BRAF V600e-mutated and BRAF fusion-positive pediatric LGG, respectively. VC ranked second. As high as 47.8% of North American centers would use conformal radiation for younger children with non-neurofibromatosis type 1 LGG after failing 2 to 3 chemotherapy regimens. Overall, 87% (87%) of North American institutions obtain some type of routine molecular testing for non-neurofibromatosis type 1-associated pediatric LGG cases. Less than 60% of centers obtain routine H3 K27M molecular testing for pediatric LGG with a midline location.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Internet , Terapia Recuperativa , Neoplasias Encefálicas/patología , Carboplatino/administración & dosificación , Niño , Preescolar , Progresión de la Enfermedad , Glioma/patología , Humanos , Lactante , Clasificación del Tumor , América del Norte , Encuestas y Cuestionarios , Vinblastina/administración & dosificación , Vincristina/administración & dosificación
14.
Nano Lett ; 20(3): 1952-1958, 2020 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-32023411

RESUMEN

The facet-dependent electrical conductivity properties of silicon wafers result from significant band structure differences and variations in bond length, bond geometry, and frontier orbital electron distribution between the metal-like and semiconducting planes of silicon. To further understand the emergence of conductivity facet effects, electrochemical impedance measurements were conducted on intrinsic Si {100}, {110}, and {111} wafers. The attempt-to-escape frequency, obtained from temperature-dependent capacitance versus applied frequency curves, and other parameters derived from typical semiconductor property measurements were used to construct a diagram of the trap energy level (Et) and the amount of trap states Nt(Et). The trap states are located 0.61-0.72 eV above the silicon conduction band. Compared to {100} and {110} wafers, Si {111} wafer shows far less densities of trap states over the range of -0.2 to 2 V. Since these trap states inhibit direct electron excitation to the conduction band, the {111} wafer having much fewer trap states presents the best electrical conductivity property. Impedance data also provide facet-specific carrier lifetimes. The {111} surface gives consistently the lowest carrier lifetime, which reflects its high electrical conductivity. Lastly, ultraviolet photoelectron spectra and diffuse reflectance spectra were taken to obtain Schottky barriers between Ag and contacting Si wafers. The most conductive {111} surface presenting the largest Schottky barrier means the degrees of surface band bending used to explain facet-dependent electrical behaviors cannot be reliably attained this way.

15.
J Am Chem Soc ; 142(30): 12976-12986, 2020 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-32597176

RESUMEN

Covalent triazine frameworks are an emerging material class that have shown promising performance for a range of applications. In this work, we report on a metal-assisted and solvent-mediated reaction between calcium carbide and cyanuric chloride, as cheap and commercially available precursors, to synthesize two-dimensional triazine structures (2DTSs). The reaction between the solvent, dimethylformamide, and cyanuric chloride was promoted by calcium carbide and resulted in dimethylamino-s-triazine intermediates, which in turn undergo nucleophilic substitutions. This reaction was directed into two dimensions by calcium ions derived from calcium carbide and induced the formation of 2DTSs. The role of calcium ions to direct the two-dimensionality of the final structure was simulated using DFT and further proven by synthesizing molecular intermediates. The water content of the reaction medium was found to be a crucial factor that affected the structure of the products dramatically. While 2DTSs were obtained under anhydrous conditions, a mixture of graphitic material/2DTSs or only graphitic material (GM) was obtained in aqueous solutions. Due to the straightforward and gram-scale synthesis of 2DTSs, as well as their photothermal and photodynamic properties, they are promising materials for a wide range of future applications, including bacteria and virus incapacitation.

16.
J Viral Hepat ; 27(7): 699-708, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32096313

RESUMEN

Single-visit cures for chronic hepatitis C are lacking. We conducted two clinical studies towards the goal of developing a regimen for single-visit cure. In a randomized, open-label, Phase 2 study (RG101-04), investigators enrolled 26 adult chronic hepatitis C patients to evaluate safety and efficacy of single subcutaneous injection of RG-101 (4 mg/kg) and daily oral tablets of GSK2878175 (20 mg) for 6, 9 or 12 weeks. In another randomized, double-blind, single dose Phase 1 study (RG101-06), investigators enrolled 18 healthy men to assess safety and PK of GSK2878175 long-acting injectable at 100, 200 or 400 mg. In RG101-04, SVR48 rates were 50%, 56% and 89%, for the 6, 9 and 12 weeks treatment arms, respectively. All AEs were mild or moderate in severity (≤Grade 2). In RG101-06 at 400 mg, the mean duration of GSK2878175 plasma levels above in vitro therapeutic concentrations for GT1b was 41 days. All AEs were Grade 2 or less. In conclusion, single injection of RG-101 combined with 12 weeks of GSK2878175 oral tablets was generally well tolerated and resulted in high SVR rates in chronic hepatitis C patients. Single injections of GSK2878175 long-acting injectable were also well tolerated; however, higher doses would be required if used in combination with RG-101 to achieve the SVR rates observed in the oral combination study to enable a single-visit curative regimen.


Asunto(s)
Acetilgalactosamina/análogos & derivados , Antivirales , Benzofuranos , Hepatitis C Crónica , Oligonucleótidos , Acetilgalactosamina/uso terapéutico , Adulto , Antivirales/uso terapéutico , Benzofuranos/uso terapéutico , Método Doble Ciego , Voluntarios Sanos , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Masculino , Oligonucleótidos/uso terapéutico , Resultado del Tratamiento
17.
Pharmacol Res ; 155: 104680, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32032665

RESUMEN

Friedreich's ataxia (FA) is due to deficiency of the mitochondrial protein, frataxin, which results in multiple pathologies including a deadly, hypertrophic cardiomyopathy. Frataxin loss leads to deleterious accumulations of redox-active, mitochondrial iron, and suppressed mitochondrial bioenergetics. Hence, there is an urgent need to develop innovative pharmaceuticals. Herein, the activity of the novel compound, 6-methoxy-2-salicylaldehyde nicotinoyl hydrazone (SNH6), was assessed in vivo using the well-characterized muscle creatine kinase (MCK) conditional frataxin knockout (KO) mouse model of FA. The design of SNH6 incorporated a dual-mechanism mediating: (1) NAD+-supplementation to restore cardiac bioenergetics; and (2) iron chelation to remove toxic mitochondrial iron. In these studies, MCK wild-type (WT) and KO mice were treated for 4-weeks from the asymptomatic age of 4.5-weeks to 8.5-weeks of age, where the mouse displays an overt cardiomyopathy. SNH6-treatment significantly elevated NAD+ and markedly increased NAD+ consumption in WT and KO hearts. In SNH6-treated KO mice, nuclear Sirt1 activity was also significantly increased together with the NAD+-metabolic product, nicotinamide (NAM). Therefore, NAD+-supplementation by SNH6 aided mitochondrial function and cardiac bioenergetics. SNH6 also chelated iron in cultured cardiac cells and also removed iron-loading in vivo from the MCK KO heart. Despite its dual beneficial properties of supplementing NAD+ and chelating iron, SNH6 did not mitigate cardiomyopathy development in the MCK KO mouse. Collectively, SNH6 is an innovative therapeutic with marked pharmacological efficacy, which successfully enhanced cardiac NAD+ and nuclear Sirt1 activity and reduced cardiac iron-loading in MCK KO mice. No other pharmaceutical yet designed exhibits both these effective pharmacological properties.


Asunto(s)
Aldehídos/uso terapéutico , Cardiomiopatías/tratamiento farmacológico , Ataxia de Friedreich/tratamiento farmacológico , Hidrazonas/uso terapéutico , Quelantes del Hierro/uso terapéutico , NAD/metabolismo , Adenosina Trifosfato/metabolismo , Aldehídos/farmacología , Animales , Cardiomiopatías/metabolismo , Línea Celular , Forma MM de la Creatina-Quinasa/genética , Modelos Animales de Enfermedad , Ataxia de Friedreich/metabolismo , Hidrazonas/farmacología , Hierro/metabolismo , Quelantes del Hierro/farmacología , Proteínas de Unión a Hierro/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Cardíacas/metabolismo , Ratas , Frataxina
18.
Pediatr Blood Cancer ; 67(4): e28199, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32020723

RESUMEN

Chimeric antigen receptor T cells (CAR-T) are an effective and potentially durable treatment for refractory and multiply relapsed B-cell acute lymphoblastic leukemia. Neurotoxicity is frequent after CAR-T cell therapy. Mechanisms driving neurotoxicity are incompletely understood, and symptoms can range from transient and mild to severe and life-threatening. Providers have exercised caution in providing CAR-T to patients with neurological comorbidities or extramedullary disease. Here, we report three patients with prior significant neurologic morbidity who safely tolerated CAR-T cell infusion after bridging therapy with conventional chemotherapy.


Asunto(s)
Inmunoterapia Adoptiva/efectos adversos , Enfermedades del Sistema Nervioso , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Adolescente , Niño , Preescolar , Comorbilidad , Humanos , Masculino , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Enfermedades del Sistema Nervioso/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico por imagen , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia
19.
Neurosurg Focus ; 49(5): E18, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33130616

RESUMEN

OBJECTIVE: Spine surgery is especially susceptible to malpractice claims. Critics of the US medical liability system argue that it drives up costs, whereas proponents argue it deters negligence. Here, the authors study the relationship between malpractice claim density and outcomes. METHODS: The following methods were used: 1) the National Practitioner Data Bank was used to determine the number of malpractice claims per 100 physicians, by state, between 2005 and 2010; 2) the Nationwide Inpatient Sample was queried for spinal fusion patients; and 3) the Area Resource File was queried to determine the density of physicians, by state. States were categorized into 4 quartiles regarding the frequency of malpractice claims per 100 physicians. To evaluate the association between malpractice claims and death, discharge disposition, length of stay (LOS), and total costs, an inverse-probability-weighted regression-adjustment estimator was used. The authors controlled for patient and hospital characteristics. Covariates were used to train machine learning models to predict death, discharge disposition not to home, LOS, and total costs. RESULTS: Overall, 549,775 discharges following spinal fusions were identified, with 495,640 yielding state-level information about medical malpractice claim frequency per 100 physicians. Of these, 124,425 (25.1%), 132,613 (26.8%), 130,929 (26.4%), and 107,673 (21.7%) were from the lowest, second-lowest, second-highest, and highest quartile states, respectively, for malpractice claims per 100 physicians. Compared to the states with the fewest claims (lowest quartile), surgeries in states with the most claims (highest quartile) showed a statistically significantly higher odds of a nonhome discharge (OR 1.169, 95% CI 1.139-1.200), longer LOS (mean difference 0.304, 95% CI 0.256-0.352), and higher total charges (mean difference [log scale] 0.288, 95% CI 0.281-0.295) with no significant associations for mortality. For the machine learning models-which included medical malpractice claim density as a covariate-the areas under the curve for death and discharge disposition were 0.94 and 0.87, and the R2 values for LOS and total charge were 0.55 and 0.60, respectively. CONCLUSIONS: Spinal fusion procedures from states with a higher frequency of malpractice claims were associated with an increased odds of nonhome discharge, longer LOS, and higher total charges. This suggests that medicolegal climate may potentially alter practice patterns for a given spine surgeon and may have important implications for medical liability reform. Machine learning models that included medical malpractice claim density as a feature were satisfactory in prediction and may be helpful for patients, surgeons, hospitals, and payers.


Asunto(s)
Mala Praxis , Fusión Vertebral , Humanos , Tiempo de Internación , Aprendizaje Automático , Alta del Paciente , Fusión Vertebral/efectos adversos , Estados Unidos
20.
Arthroscopy ; 36(4): 1039-1044, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31805385

RESUMEN

PURPOSE: To evaluate the analgesic effect of preoperative fascia iliaca block on postoperative morphine equivalent dose, pain level, and patient satisfaction for patients electing to undergo primary hip arthroscopic labral repair with osteochondroplasty. METHODS: This prospective study included 60 patients (fascia iliaca block group: n = 27; control group: n = 33) undergoing elective arthroscopic hip surgery by a single board-certified orthopedic surgeon, fellowship trained in hip arthroscopy. Participants for the study included patients older than 10 years of age and younger than 85 years of age, American Society of Anesthesiologists classifications I to III, diagnosed with symptomatic femoroacetabular impingement, and/or hip labral tear, and/or cartilage damage, and electing to undergo arthroscopic hip surgery. Patients were randomized by surgical date to receive preoperative fascia iliaca block or control (no fascia iliaca block). Preoperative fascia iliaca block was administered by 1 of 4 board certified anesthesiologists using identical anesthetic (35-40 mL ropivacaine 0.35%). Postoperative morphine equivalent dose, self-reported pain level (visual analog scale) and patient satisfaction were measure postoperatively. RESULTS: There were no significant differences between the control group and the fascia iliaca block group in sex, age, height, weight, or body mass index. There was a significant difference between the 2 groups in distribution of American Society of Anesthesiologists classification (p = .031). There were no significant differences in postoperative morphine equivalent dose for patients receiving fascia iliaca block compared with the control group. There were no significant differences in self-reported visual analog scale pain and patient satisfaction between the 2 groups at any of the measured time points following surgery. CONCLUSIONS: Based on the results of this study, routine preoperative fascia iliaca block for elective hip arthroscopic labral repair and treatment of femoroacetabular impingement is not recommended. LEVEL OF EVIDENCE: Level II, prospective single blinded randomized study.


Asunto(s)
Artroscopía , Cartílago Articular/cirugía , Pinzamiento Femoroacetabular/cirugía , Articulación de la Cadera/cirugía , Bloqueo Nervioso , Adolescente , Adulto , Cartílago Articular/lesiones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/prevención & control , Satisfacción del Paciente , Cuidados Preoperatorios , Estudios Prospectivos , Método Simple Ciego , Escala Visual Analógica , Adulto Joven
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