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1.
Conserv Biol ; : e14314, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105482

RESUMO

The rapid decline of global biodiversity has engendered renewed debate about the social, economic, and political factors contributing to it. Specifically, there is little understanding of the role that political ideology within a country (e.g., nationalism, conservatism, socialism) plays in determining biodiversity outcomes. We used negative binomial generalized linear models to investigate the importance of national regime ideology in predicting threatened animal species and protected area establishment compared with other factors that affect biodiversity outcomes, such as gross domestic product, inequality, and democracy. For threatened animals, the model with the highest Akaike weight suggested adverse biodiversity outcomes arose from larger gross domestic product (ß = 0.120, p < 0.001). However, nationalism (ß = 0.371, p < 0.01) and socialism (ß = 0.293, p < 0.05) were also significantly associated with increased proportions of threatened species. For protected areas, the model with the highest Akaike weight suggested increases in democracy (ß = 0.880, p < 0.001) led to a rise in relative protected area estate. Conservative regime ideology was also associated with greater protected area estate, although this did not increase the weight of evidence in support of the best models. These findings highlight the relevance of political ideology for predicting biodiversity outcomes at a national scale and illustrate opportunities to tailor policies and advocacy to promote biodiversity conservation more effectively. By targeting appropriate messaging and political advocacy, conservationists can improve the likelihood that politicians and their nations will participate in positive biodiversity actions.


El papel de la ideología del régimen nacional para la predicción de resultados de biodiversidad Resumen El rápido declive de la biodiversidad mundial ha suscitado un renovado debate sobre los factores sociales, económicos y políticos que contribuyen a él. En concreto, se conoce poco el papel que desempeña la ideología política dentro de un país (por ejemplo, el nacionalismo, el conservadurismo o el socialismo) a la hora de determinar los resultados en materia de biodiversidad. Utilizamos modelos lineales generalizados binomiales negativos para investigar la importancia de la ideología del régimen nacional a la hora de predecir las especies animales amenazadas y el establecimiento de áreas protegidas en comparación con otros factores que afectan a los resultados de la biodiversidad, como el producto interno bruto, la desigualdad y la democracia. En el caso de los animales amenazados, el modelo con la mayor ponderación de Akaike sugirió que los resultados adversos para la biodiversidad se debían a un mayor producto interno bruto (ß = 0,120, p < 0,001). Sin embargo, el nacionalismo (ß = 0,371, p < 0,01) y el socialismo (ß = 0,293, p < 0,05) también se asociaron significativamente con una mayor proporción de especies amenazadas. En el caso de las áreas protegidas, el modelo con la mayor ponderación de Akaike sugirió que el aumento de la democracia (ß = 0,880, p < 0,001) conducía a un aumento de la extensión relativa de las áreas protegidas. La ideología conservadora del régimen también se asoció con una mayor superficie de áreas protegidas, aunque no aumentó el peso de la evidencia en apoyo de los mejores modelos. Estos resultados resaltan la importancia de la ideología política para predecir los resultados de la biodiversidad a escala nacional e ilustran las oportunidades de adaptar las políticas y la defensa para promover la conservación de la biodiversidad de manera más eficaz. Si se orientan los mensajes y la promoción política de forma adecuada, los conservacionistas pueden mejorar la probabilidad de que los políticos y sus naciones participen en acciones positivas para la biodiversidad.

2.
J Neuropsychiatry Clin Neurosci ; : appineuropsych20240006, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39113494

RESUMO

OBJECTIVE: Cognitive impairment is a common nonmotor symptom in Parkinson's disease (PD). Individuals of Latino background are traditionally underrepresented in research on PD. Despite the fact that Latinos comprise 18% of the U.S. population, they commonly make up less than 5% of samples in studies of PD. Emerging evidence suggests that Latino individuals with PD may experience disparities relative to White non-Latinos in terms of having more severe motor symptoms, more severe depressive symptoms, and worse health-related quality of life. The purpose of the present study was to investigate differences in cognitive performance between Latino and White non-Latino individuals with PD and examine correlates of cognitive performance. METHODS: Data were obtained from the Parkinson's Progression Markers Initiative. Participants included 60 Latino individuals with PD and 1,009 White non-Latino individuals with PD, all of whom were followed annually for up to 5 years. Participants completed neuropsychological tests of attention and working memory, processing speed, visuospatial functioning, verbal fluency, and immediate and delayed memory and recall. RESULTS: Relative to White non-Latino individuals with PD, Latino individuals with PD had significantly lower scores on the global measure of cognitive functioning, a test of processing speed, and tests of working memory and attention. Years of education was the strongest correlate of performance in these three cognitive domains among individuals in the Latino group. CONCLUSIONS: These findings provide initial evidence of disparities in cognitive functioning among Latino individuals with PD. Educational disadvantages may be one potential driver of these disparities.

3.
BMC Pregnancy Childbirth ; 24(1): 594, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256691

RESUMO

BACKGROUND: Diabetes in pregnancy is associated with short and long-term adverse health outcomes for mothers and babies. The condition disproportionately impacts Pacific, Maaori, and Indian pregnancies. Those with diabetes are offered intensive support during pregnancy, but in many centres, no additional support following birth beyond routine care. The aim of this study was to determine the postpartum needs for mothers and whaanau (family) impacted by diabetes in pregnancy, to inform co-design of a new service to improve metabolic and developmental outcomes for infants. METHODS: Pregnancies complicated by diabetes were identified using a local diabetes registry. Mothers with a diagnosis of GDM or T2DM and gave birth between January 2022 -June 2022 were eligible for the study. A total of 19 parents (18 mothers, 1 father) were interviewed. Participants primarily identified as Maaori (6), Pacific (6), Indian (3), Asian (2), and New Zealand European (2). Interviews took place between December 2022 and February 2023, between 5-13 months post-pregnancy. Interviews facilitated by an externally contracted local Pacific mother, with a professional background in social work were conducted using Koorero and Talanoa, Maaori and Pacific methods of qualitative data collection, to capture the lived experiences of participants. A multidisciplinary group reviewed and coded interview transcripts. Themes were presented back to participants and stakeholders for feedback and refinement. Four over-arching themes were illustrated with exemplar quotes. RESULTS: Four themes described the importance of 1) Finding a balance between what is "best practice" and what is best for me, my baby and my whaanau, 2) The need for individualised and culturally appropriate care, 3) Centrality of whaanau and family to the pregnancy and postpartum journey, 4) The pervasive negative impact of diabetes on taha hinegaro (well-being) beyond childbirth. CONCLUSION: People who are affected by diabetes in pregnancy have ongoing physical, psychological, and social needs. A holistic, whaanau-centred approach is required to ensure optimal health and well-being outcomes of mothers, infants and whaanau. The findings of this study will inform a new targeted model of care for infants and whaanau affected by diabetes in pregnancy.


Assuntos
Diabetes Gestacional , Mães , Período Pós-Parto , Gravidez em Diabéticas , Humanos , Feminino , Gravidez , Período Pós-Parto/psicologia , Adulto , Mães/psicologia , Diabetes Gestacional/psicologia , Nova Zelândia , Gravidez em Diabéticas/psicologia , Lactente , Pesquisa Qualitativa , Masculino , Estilo de Vida , Recém-Nascido , Diabetes Mellitus Tipo 2/psicologia
4.
Angew Chem Int Ed Engl ; 63(4): e202312130, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-37699142

RESUMO

The removal of lead from commercialized perovskite-oxide-based piezoceramics has been a recent major topic in materials research owing to legislation in many countries. In this regard, Sn(II)-perovskite oxides have garnered keen interest due to their predicted large spontaneous electric polarizations and isoelectronic nature for substitution of Pb(II) cations. However, they have not been considered synthesizable owing to their high metastability. Herein, the perovskite lead hafnate, i.e., PbHfO3 in space group Pbam, is shown to react with SnClF at a low temperature of 300 °C, and resulting in the first complete Sn(II)-for-Pb(II) substitution, i.e. SnHfO3 . During this topotactic transformation, a high purity and crystallinity is conserved with Pbam symmetry, as confirmed by X-ray and electron diffraction, elemental analysis, and 119 Sn Mössbauer spectroscopy. In situ diffraction shows SnHfO3 also possesses reversible phase transformations and is potentially polar between ≈130-200 °C. This so-called 'de-leadification' is thus shown to represent a highly useful strategy to fully remove lead from perovskite-oxide-based piezoceramics and opening the door to new explorations of polar and antipolar Sn(II)-oxide materials.

5.
J Exp Bot ; 74(21): 6417-6430, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37611151

RESUMO

Phosphorus is essential to plant growth and agricultural crop yields, yet the challenges associated with phosphorus fertilization in agriculture, such as aquatic runoff pollution and poor phosphorus bioavailability, are increasingly difficult to manage. Comprehensively understanding the dynamics of phosphorus uptake and signaling mechanisms will inform the development of strategies to address these issues. This review describes regulatory mechanisms used by specific tissues in the root apical meristem to sense and take up phosphate from the rhizosphere. The major regulatory mechanisms and related hormone crosstalk underpinning phosphate starvation responses, cellular phosphate homeostasis, and plant adaptations to phosphate starvation are also discussed, along with an overview of the major mechanism of plant systemic phosphate starvation responses. Finally, this review discusses recent promising genetic engineering strategies for improving crop phosphorus use and computational approaches that may help further design strategies for improved plant phosphate acquisition. The mechanisms and approaches presented include a wide variety of species including not only Arabidopsis but also crop species such as Oryza sativa (rice), Glycine max (soybean), and Triticum aestivum (wheat) to address both general and species-specific mechanisms and strategies. The aspects of phosphorus deficiency responses and recently employed strategies of improving phosphate acquisition that are detailed in this review may provide insights into the mechanisms or phenotypes that may be targeted in efforts to improve crop phosphorus content and plant growth in low phosphorus soils.


Assuntos
Arabidopsis , Oryza , Fosfatos , Fósforo , Homeostase , Transporte Biológico , Produtos Agrícolas , Triticum/genética , Oryza/genética , Raízes de Plantas/genética
6.
Nanotechnology ; 34(12)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36538824

RESUMO

Hf0.5Zr0.5O2(HZO) thin films are promising candidates for non-volatile memory and other related applications due to their demonstrated ferroelectricity at the nanoscale and compatibility with Si processing. However, one reason that HZO has not been fully scaled into industrial applications is due to its deleterious wake-up and fatigue behavior which leads to an inconsistent remanent polarization during cycling. In this study, we explore an interfacial engineering strategy in which we insert 1 nm Al2O3interlayers at either the top or bottom HZO/TiN interface of sequentially deposited metal-ferroelectric-metal capacitors. By inserting an interfacial layer while limiting exposure to the ambient environment, we successfully introduce a protective passivating layer of Al2O3that provides excess oxygen to mitigate vacancy formation at the interface. We report that TiN/HZO/TiN capacitors with a 1 nm Al2O3at the top interface demonstrate a higher remanent polarization (2Pr∼ 42µC cm-2) and endurance limit beyond 108cycles at a cycling field amplitude of 3.5 MV cm-1. We use time-of-flight secondary ion mass spectrometry, energy dispersive spectroscopy, and grazing incidence x-ray diffraction to elucidate the origin of enhanced endurance and leakage properties in capacitors with an inserted 1 nm Al2O3layer. We demonstrate that the use of Al2O3as a passivating dielectric, coupled with sequential ALD fabrication, is an effective means of interfacial engineering and enhances the performance of ferroelectric HZO devices.

7.
J Neuropsychiatry Clin Neurosci ; 35(2): 165-170, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36128680

RESUMO

OBJECTIVE: Parkinson's disease (PD) is a neurodegenerative movement disorder that is a result of dopamine depletion in the basal ganglia. Individuals with a PD diagnosis experience motor symptoms (e.g., tremors) and nonmotor symptoms (e.g., cognitive decline). Previous studies suggest that progression of cognitive dysfunction in other neurologic populations can be predicted by cumulative head injuries. The study examined the association between lifelong number of head injuries and nonmotor outcomes (cognitive complaints, depression, and quality of life). METHODS: Participants consisted of 3,483 individuals with PD diagnoses who were enrolled in the Fox Insight study. Participants completed a self-report questionnaire to quantify the number of head injuries experienced throughout life. Participants also completed measures of nonmotor outcomes (cognitive complaints, depression, and quality of life) every 6 months over a 3-year period. RESULTS: Cognitive complaints were more common among those experiencing more head injuries. Further, more severe depression and greater difficulties in quality of life were reported among individuals experiencing a greater number of head injuries. Additional analyses revealed the effect between cognitive complaints and number of head injuries was driven by individuals who experienced five or more head injuries in their lifetime. CONCLUSIONS: Among individuals with PD, a patient report of past head injuries may have prognostic implications for important nonmotor outcomes. Report of multiple head injuries may be particularly concerning.


Assuntos
Disfunção Cognitiva , Traumatismos Craniocerebrais , Transtorno Depressivo , Doença de Parkinson , Humanos , Qualidade de Vida/psicologia , Traumatismos Craniocerebrais/complicações
8.
Proc Natl Acad Sci U S A ; 117(42): 26482-26493, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33020290

RESUMO

Obesity affects over 2 billion people worldwide and is accompanied by peripheral neuropathy (PN) and an associated poorer quality of life. Despite high prevalence, the molecular mechanisms underlying the painful manifestations of PN are poorly understood, and therapies are restricted to use of painkillers or other drugs that do not address the underlying disease. Studies have demonstrated that the gut microbiome is linked to metabolic health and its alteration is associated with many diseases, including obesity. Pathologic changes to the gut microbiome have recently been linked to somatosensory pain, but any relationships between gut microbiome and PN in obesity have yet to be explored. Our data show that mice fed a Western diet developed indices of PN that were attenuated by concurrent fecal microbiome transplantation (FMT). In addition, we observed changes in expression of genes involved in lipid metabolism and calcium handling in cells of the peripheral nerve system (PNS). FMT also induced changes in the immune cell populations of the PNS. There was a correlation between an increase in the circulating short-chain fatty acid butyrate and pain improvement following FMT. Additionally, butyrate modulated gene expression and immune cells in the PNS. Circulating butyrate was also negatively correlated with distal pain in 29 participants with varied body mass index. Our data suggest that the metabolite butyrate, secreted by the gut microbiome, underlies some of the effects of FMT. Targeting the gut microbiome, butyrate, and its consequences may represent novel viable approaches to prevent or relieve obesity-associated neuropathies.


Assuntos
Transplante de Microbiota Fecal/métodos , Obesidade/microbiologia , Doenças do Sistema Nervoso Periférico/terapia , Animais , Butiratos/metabolismo , Dieta Hiperlipídica , Dieta Ocidental , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Expressão Gênica , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Microbiota , Neuralgia/metabolismo , Obesidade/fisiopatologia , Sistema Nervoso Periférico/metabolismo , Sistema Nervoso Periférico/fisiologia
9.
J Foot Ankle Surg ; 62(3): 458-464, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36496339

RESUMO

Intravascular endothelial hyperplasia is a benign soft tissue mass rarely reported in the foot. Advanced imaging and confirming a benign diagnosis are critical for any soft tissue mass. This paper identifies 2 patients that developed intravascular endothelial hyperplasia tumors which required surgical excision. A 17-year-old male patient presented to clinic complaining of a painful bump to the arch of his right foot which he related to an injury 9 months prior. Magnetic resonance imaging of the right foot revealed a mass within the plantar subcutaneous fat that was serpiginous in nature similar to adjacent branching vessels favoring a low-flow vascular malformation. A 38-year-old female with Multiple Sclerosis presented with complaints of persistent symptoms of pain to the 1st interspace, difficult ambulation and neuritis. Ultrasound and MRI observed solid, multilobulated mass, with internal vascular malformation, MRI describing intrinsic involvement along the abductor musculature and flexor tendons. Both lesions were surgically excised and sent for pathology. Pathology report indicated a diagnosis of intravascular papillary endothelial hyperplasia or Masson's tumor in both cases. Pathology diagnosis of intravascular papillary endothelial hyperplasia is generally good with wide resection leading to low recurrence rates. Both patients in the current study have progressed postoperatively with resolution of symptoms and without recurrence.


Assuntos
Hemangioendotelioma , Malformações Vasculares , Neoplasias Vasculares , Masculino , Feminino , Humanos , Adulto , Adolescente , Hemangioendotelioma/diagnóstico por imagem , Hemangioendotelioma/cirurgia , Hiperplasia/cirurgia , Hiperplasia/patologia , Pé/diagnóstico por imagem , Pé/cirurgia , Pé/patologia , Neoplasias Vasculares/patologia , Malformações Vasculares/diagnóstico , Malformações Vasculares/patologia , Diagnóstico Diferencial
10.
Chemistry ; 28(33): e202200479, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35389540

RESUMO

Recently, many new, complex, functional oxides have been discovered with the surprising use of topotactic ion-exchange reactions on close-packed structures, such as found for wurtzite, rutile, perovskite, and other structure types. Despite a lack of apparent cation-diffusion pathways in these structure types, synthetic low-temperature transformations are possible with the interdiffusion and exchange of functional cations possessing ns2 stereoactive lone pairs (e. g., Sn(II)) or unpaired ndx electrons (e. g., Co(II)), targeting new and favorable modulations of their electronic, magnetic, or catalytic properties. This enables a synergistic blending of new functionality to an underlying three-dimensional connectivity, i. e., [-M-O-M-O-]n , that is maintained during the transformation. In many cases, this tactic represents the only known pathway to prepare thermodynamically unstable solids that otherwise would commonly decompose by phase segregation, such as that recently applied to the discovery of many new small bandgap semiconductors.

11.
Am J Geriatr Psychiatry ; 30(6): 664-674, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34922823

RESUMO

OBJECTIVE: Greater depressive symptoms are associated with worse cognitive functions in Parkinson's disease (PD); however, it is unclear what underlying factors drive this association. Apathy commonly develops in PD and may be a pathway through which depressive symptoms negatively influence cognition. Prior research examining depressive symptoms, apathy, and cognition in PD is limited by being predominantly cross-sectional. This study examined the role of apathy as a within- and between-person mediator for the longitudinal relationships between depression severity and cognitive functioning in patients with early PD. METHODS: Participants included 487 individuals newly diagnosed with PD followed annually for up to 5 years by the Parkinson's Progression Marker Initiative. At each visit, participants completed depressive symptom measures, apathy ratings, and cognitive tests. Multi-level structural equation models examined both the within- and between-person effects of depressive symptoms on cognition through apathy, controlling for demographics and motor severity. RESULTS: At the within-person level, apathy mediated the association between depressive symptoms and select cognitive functions (global cognition, attention/working memory, visuospatial functions, and immediate verbal memory; indirect effects, bootstrap p's <0.05). Significant between-person direct effects were found for depressive symptoms predicting apathy (boostrap p <0.001) and lower scores on most cognitive tests (bootstrap p's <0.05). However, the indirect effects did not reach significance, suggesting between-person mediation did not occur. CONCLUSION: Findings suggest worsening of depressive symptoms over time in patients with PD may be a risk factor for increased apathy and subsequent decline in specific cognitive functions.


Assuntos
Apatia , Doença de Parkinson , Cognição , Estudos Transversais , Depressão/psicologia , Humanos , Análise de Mediação , Doença de Parkinson/complicações , Doença de Parkinson/psicologia
12.
J Ultrasound Med ; 41(9): 2343-2353, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34927276

RESUMO

OBJECTIVES: To investigate ultrasound (US) femoroacetabular translation measurements in female athlete patients. METHODS: A prospective cross-sectional study was conducted in female athlete patients <50 years. Demographic data, Beighton score/hypermobility status, and sport participation were collected. Hip dysplasia was determined using radiographic measurements (lateral center edge angle, anterior center edge angle, Tönnis angle); femoral version angles were measured with CT or MR. Femoroacetabular translation US measures included neutral (N), neutral flexed (NF), extension external rotation/apprehension (EER) positions. Maximal difference (delta) between US measures was calculated. RESULTS: 206/349 female hips were analyzed (median age 21.2 years [range, 12-49.5]). The primary sport group was performing arts (45%, 92/206). Mean Beighton score was 5.2 (SD, 2.5) with 61% (129/206) of hips exhibiting hypermobility (Beighton score ≥5). For each additional unit of Beighton score, N US measurement increased by 0.7 mm (ß = 0.7; 95% confidence interval [CI] = 0.22-1.25; P < .001), NF by 1 mm ( ß = 0.9; 95% CI = 0.3-1.43; P = .002) and EER by 0.8 mm ( ß = 0.8; 95% CI = 0.27-1.37; P < .001) when adjusting for age and dysplasia status. A positive correlation was detected between NF (r = 0.19; 95% CI = 0.05-0.33; P = .007) and EER (r = 0.19; 95% CI = 0.05-0.32; P = .01) with Tönnis angle and a negative correlation between the delta and femoral version (r = -0.20; 95% CI = -0.35 to 0.03; P = .02). No difference in US measures was detected across sport groups (N [P = .24], NF [P = .51], EER [P = .20], delta [P = .07]). CONCLUSION: Beighton score was independently associated with dynamic US measures in female athlete patients who are not hypermobile when controlling for other factors.


Assuntos
Instabilidade Articular , Adulto , Atletas , Estudos Transversais , Feminino , Articulação do Quadril/diagnóstico por imagem , Humanos , Instabilidade Articular/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Ultrassonografia , Adulto Jovem
13.
Brain Inj ; 36(8): 921-930, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35957571

RESUMO

OBJECTIVE: Accurate assessment of balance recovery throughout treatment of a sport-related concussion is imperative. This study examined differences in balance from diagnosis to return-to-play initiation in adolescent patients post-concussion. Second, this study investigated the extent to which the Balance Error Scoring System (BESS) correlated with center-of-pressure (COP) measures. METHODS: Forty participants performed the BESS while standing on a force platform such that COP data were obtained simultaneously. Spatial and velocity COP-based measures were computed for the double-stance conditions. RESULTS: BESS scores and COP-based measures indicated improved balance performance between visits. Specifically, 62.5/65.0% of participants exhibited improved firm/foam BESS final scores, respectively, and 56.4-71.8% exhibited improved COP-based measures. However, once normative ranges were referenced to identify maintained performance, the percentage of participants who substantially improved differed from initial findings (BESS: 2.5/7.5%, COP: 48.7-69.2%). Additionally, positive correlations between balance measures were primarily found at diagnosis (r=0.33-0.53), while only three correlations were maintained at return-to-play initiation (r=0.34-0.39). CONCLUSIONS: BESS scores successfully identified poor balance performance at diagnosis when symptoms were most pronounced, but failed to accurately depict performance once balance impairment, indicated by COP-based measures, became less apparent. Further work is needed to implement more advanced balance assessments into clinical environments.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes , Adolescente , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Humanos , Equilíbrio Postural , Volta ao Esporte
14.
J Foot Ankle Surg ; 61(4): 879-885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34987007

RESUMO

Forefoot varus develops as a result of longstanding adult-acquired flatfoot deformity (AAFD). This occurs with varying degrees of deformity and flexibility. Residual forefoot varus following hindfoot realignment in AAFD can lead to lateral column loading and a persistent pronatory moment in efforts to reestablish contact between the forefoot and the ground. The Cotton osteotomy may serve as a reasonable adjunct procedure to help avoid complications and poor outcomes associated with residual forefoot varus in patients undergoing hindfoot arthrodesis for stage III AAFD. The aim of this study was to compare the radiographic outcomes in patients undergoing isolated hindfoot arthrodesis to patients undergoing hindfoot arthrodesis with adjunctive cotton osteotomy. We retrospectively reviewed 47 patients matched based upon age, sex, and comorbidities who underwent hindfoot reconstruction for the treatment of stage III AAFD between 2015 and 2019. A retrospective radiographic review was performed on standard weightbearing radiographs including anterior-posterior and lateral views preoperatively, postoperatively at the initiation of full weightbearing, and at final follow-up. Statistical analysis utilizing paired t test to calculate p values where <.05 was statistically significant. At final follow-up, radiographic measurements showed statistically significant differences in CAA, calcaneal inclination, talo-calcaneal, and talar tilt (p value <.05). The Cotton osteotomy group showed a quicker return to presurgical activity level and a decreased incident of tibiotalar valgus. Our study suggests that the Cotton osteotomy can address residual forefoot varus and potentially prevent further progression of ankle valgus in AAFD when used in combination with hindfoot arthrodesis.


Assuntos
Pé Chato , Adulto , Artrodese/métodos , Pé Chato/complicações , Pé Chato/diagnóstico por imagem , Pé Chato/cirurgia , Humanos , Osteotomia/métodos , Estudos Retrospectivos , Resultado do Tratamento
15.
J Foot Ankle Surg ; 61(5): 938-943, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34996652

RESUMO

Subtalar joint (STJ) arthrodesis is a well-established and accepted surgical procedure utilized for the treatment of various hindfoot conditions including primary or posttraumatic subtalar osteoarthritis, hindfoot valgus deformity, hindfoot varus deformity, complex acute calcaneal fracture, symptomatic residual congenital deformity, tarsal coalition, and other conditions causing pain and deformity about the hindfoot. Union rates associated with isolated subtalar joint arthrodesis are generally thought to be favorable, though reports have varied significantly, with non-union rates ranging from 0 to 46%. Various fixation constructs have been recommended for STJ arthrodesis. The purpose of this study was to compare radiographic union in a 2-screw fixation technique to a 3-screw fixation technique for patients undergoing primary isolated STJ arthrodesis. To this end, we retrospectively reviewed 54 patients; 26 in the 2-screw group and 28 in the 3-screw group. We found the median time to radiographic union to be 9 weeks for the 2-screw cohort and 7 weeks for the 3-screw cohort. Additionally, we found that the 2-screw fixation cohort had a radiographic non-union rate of 26.9% while the 3-screw cohort had no non-unions. We conclude that the use of a 3-screw construct for isolated STJ arthrodesis has a lower non-union rate and time to union when compared to the traditional 2-screw construct and should be considered as a fixation option for STJ arthrodesis.


Assuntos
Osteoartrite , Articulação Talocalcânea , Artrodese/métodos , Parafusos Ósseos , Humanos , Estudos Retrospectivos , Articulação Talocalcânea/diagnóstico por imagem , Articulação Talocalcânea/cirurgia
16.
J Foot Ankle Surg ; 61(6): 1293-1298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599073

RESUMO

Adult acquired flat foot deformity (AAFD) is a progressive, tri-planar deformity involving collapse of the medial longitudinal arch, valgus deformity of the rear foot, and abduction of the mid-foot on the rear foot. There are a wide variety of surgical treatment options for this deformity, including lateral column lengthening (LCL) which results in tri-planar correction of AAFD. We retrospectively reviewed weightbearing preoperative radiographs and weight-bearing 6-week postoperative radiographs of 34 patients with stage II AAFD who underwent LCL (with and without concurrent procedures) with a minimum of 1-year of follow up. Outcomes, including complications and postoperative differences in 6 types of angle measurements were evaluated. Radiographic evaluation showed statistically significant differences in preoperative and postoperative measures in the following angles: calcaneal inclination, Meary's, Simmons, talocalcaneal, and metatarsus adductus (each p ≤ .05). Postoperative Engel's angle difference did not reach statistical significance (p = .07). Paired t tests showed TN coverage angles increased greater with LCL plus a Cotton osteotomy as compared to isolated LCL. Additionally, there was no significant difference in TN coverage angle based on LCL graft size (p = .20). Furthermore, the distance of the osteotomy from the calcaneocuboid joint on anteroposterior and lateral radiographs did not significantly predict TN coverage angle change. Our study suggests that LCL corrects AAFD in three planes while decreasing the metatarsus adductus angle. LCL appears to be more effective when performed with a Cotton osteotomy. Wedge size (6 mm, 8 mm, 10 mm) and osteotomy location did not demonstrate a relationship with postoperative TN coverage angle or incidence of lateral column overload.

17.
J Foot Ankle Surg ; 61(5): 969-974, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35027310

RESUMO

Utilization of the talonavicular joint (TN) arthrodesis as an isolated procedure or in combination with hindfoot arthrodesis has been described in the literature for treatment of numerous hindfoot conditions. When used in isolation or with concomitant hindfoot arthrodesis, the TN joint has demonstrated nonunion rates reported as high as 37% in the literature. Despite previous research, there remains a lack of agreement upon the ideal fixation technique for TN joint arthrodesis with and without concomitant subtalar joint arthrodesis. The purpose of this study was to retrospectively compare the radiographic and clinical results of TN joint arthrodesis as part of double arthrodesis procedure utilizing 4 separate fixation constructs in the treatment of advanced hindfoot malalignment in stage III adult-acquired flatfoot deformity. We retrospectively reviewed 105 patients who underwent TN joint arthrodesis as part of double arthrodesis procedure utilizing 4 separate fixation constructs. Our results demonstrated a nonunion rate of 16.2%, with 17 nonunions identified within our patient population. One (2.4%) nonunion was observed in the 3-screw cohort, 7 (33.3%) nonunions were observed in the 2-screw cohort, 4 (16.0%) nonunions were observed in the 2-screw plus plate cohort, and 5 (29.4%) nonunions were observed in the 1-screw plus plate cohort. The difference in nonunion rate between the 4 cohorts was statistically significant. Based on these results, we conclude that the use of a 3-screw construct for TN joint arthrodesis as part of double arthrodesis procedure demonstrates a statistically significant reduction in nonunion rate and should be considered a superior fixation construct for this procedure.


Assuntos
Pé Chato , Articulações Tarsianas , Adulto , Artrodese/métodos , Parafusos Ósseos , Pé Chato/diagnóstico por imagem , Pé Chato/cirurgia , Humanos , Estudos Retrospectivos , Articulações Tarsianas/diagnóstico por imagem , Articulações Tarsianas/cirurgia
18.
J Foot Ankle Surg ; 61(6): 1255-1262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35346576

RESUMO

Tarsometatarsal joint arthrodesis is a commonly accepted procedure for hallux valgus associated with severe deformity and first ray hypermobility or medial column instability. This study evaluates the correction of hallux valgus deformity and the maintenance of correction with and without the use of a stabilization screw between the first and second metatarsal bases. Through retrospective review of first tarsometatarsal joint arthrodesis within our institution we evaluated 63 patients. Twenty-seven patients did not have a first to second metatarsal base screw and were placed into the no screw cohort. Thirty-six patients did have a first to second metatarsal base screw and were placed into the screw cohort. This study population had an osseous union rate of 95%. Clinical and radiographic recurrence occurred in 5 of 63 patients (8%). At 1-y postop the measurements demonstrated that the screw cohort had an average intermetatarsal angle correction of 11.6 degrees while the no screw cohort had an average correction of 7.8 degrees. Additionally, at 1-y postop the screw cohort had greater maintenance of the intermetatarsal angle correction with an average change of 0.5 degrees compared to 2.3 degrees in the no screw cohort. We conclude that the addition of the stabilization screw improves the first tarsometatarsal joint arthrodesis construct resulting in a greater degree of realignment and maintenance of correction.

19.
Nanotechnology ; 32(48)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34407525

RESUMO

Ferroelectric random-access memory (FRAM) based on conventional ferroelectric materials is a non-volatile memory with fast read/write operations, high endurance, and 10 years of data retention time. However, it suffers from destructive read-out operation and lack of CMOS compatibility. HfO2-based ferroelectric tunnel junctions (FTJ) may compensate for the shortcomings of FRAM by its CMOS compatibility, fast operation speed, and non-destructive readout operation. In this study, we investigate the effect of ferroelectric and interface film thickness on the tunneling electroresistance or ON/OFF current ratio of the Hf0.5Zr0.5O2/Al2O3based FTJ device. Integrating a thick ferroelectric layer (i.e. 12 nm Hf0.5Zr0.5O2) with a thin interface layer (i.e. 1 nm Al2O3) resulted in an ON/OFF current ratio of 78. Furthermore, to elucidate the relationship between ON/OFF current ratio and interfacial properties, the Hf0.5Zr0.5O2-Al2O3films and Ge-Al2O3interfaces are examined via time-of-flight secondary ion mass spectrometry depth profiling mode. A bilayer oxide heterostructure (Hf0.5Zr0.5O2/Al2O3) is deposited by atomic layer deposition (ALD) on the Ge substrate. The ON/OFF current ratio is enhanced by an order of magnitude when the Hf0.5Zr0.5O2film deposition mode is changed from exposure (H2O) ALD to sequential plasma (sequential O2-H2) ALD. Moreover, the interfacial engineering approach based on thein situALD H2-plasma surface pre-treatment of Ge increases the ON/OFF current ratio from 9 to 38 by reducing the interfacial trap density state at the Ge-Al2O3interface and producing Al2O3with fewer oxygen vacancies as compared to the wet etch (HF + H2O rinse) treatment of the Ge substrate. This study provides evidence of strong coupling between Hf0.5Zr0.5O2and Al2O3films in controlling the ON/OFF current ratio of the FTJ.

20.
Adv Chromatogr ; 58: 1-74, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36186535

RESUMO

Affinity chromatography is a technique that uses a stationary phase based on the supramolecular interactions that occur in biological systems or mimics of these systems. This method has long been a popular tool for the isolation, measurement, and characterization of specific targets in complex samples. This review discusses the basic concepts of this method and examines recent developments in affinity chromatography and related supramolecular separation methods. Topics that are examined include advances that have occurred in the types of supports, approaches to immobilization, and binding agents that are employed in this method. New developments in the applications of affinity chromatography are also summarized, including an overview on the use of this method for biochemical purification, sample preparation or analysis, chiral separations, and biointeraction studies.

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