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1.
Ophthalmic Plast Reconstr Surg ; 40(3): 331-335, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38624153

RESUMO

PURPOSE: Pilot studies suggest that waiting 15 minutes after a subcutaneous tranexamic acid injection is associated with decreased intraoperative bleeding and postoperative ecchymosis in eyelid surgery. The outcomes of commencing eyelid surgery immediately after injection without a waiting period remain unexplored. METHODS: This prospective, randomized, multicenter, double-masked, controlled study examined bilateral symmetric upper and/or lower lid blepharoplasty or ptosis repair. Patients received tranexamic acid in 1 eyelid and control in the contralateral eyelid. The surgeon recorded the side with more intraoperative bleeding. Two masked graders evaluated periocular ecchymosis at postoperative day 0 and postoperative week 1 (POW 1) with a 5-point scale. At POW 1, patients reported subjective grading of bruising as increased on 1 side or similar on both sides. Results were analyzed with Wilcoxon signed-rank and sign tests. RESULTS: Of 130 patients, there was less eyelid ecchymosis on the tranexamic side at postoperative day 0 ( p = 0.001) and POW 1 ( p < 0.001). By surgery type, the 69 levator advancement surgeries had significantly less ecchymosis at postoperative day 0 ( p < 0.001) and POW 1 ( p = 0.001), while upper eyelid blepharoplasty, combined upper and lower lid blepharoplasty, and conjunctivomullerectomy trended toward significance. Of 68 patients reporting a POW 1 grading, 69% reported less bruising on the tranexamic side ( p < 0.001). Intraoperative bleeding was not significantly different between sides ( p = 0.930). CONCLUSIONS: Without a postinjection waiting period, subcutaneous tranexamic acid for eyelid surgery significantly decreased postoperative ecchymosis on postoperative day 0 and POW 1 but did not affect intraoperative bleeding. Subcutaneous tranexamic acid was not associated with any complications.


Assuntos
Antifibrinolíticos , Blefaroplastia , Blefaroptose , Equimose , Pálpebras , Hemorragia Pós-Operatória , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/administração & dosagem , Antifibrinolíticos/administração & dosagem , Estudos Prospectivos , Método Duplo-Cego , Blefaroplastia/métodos , Blefaroplastia/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/prevenção & controle , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/etiologia , Idoso , Pálpebras/cirurgia , Equimose/etiologia , Equimose/prevenção & controle , Equimose/diagnóstico , Blefaroptose/cirurgia , Adulto , Perda Sanguínea Cirúrgica/prevenção & controle
2.
Histopathology ; 83(5): 669-684, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37526026

RESUMO

Assessment of sentinel lymph node status is an important step in the evaluation of patients with melanoma for both prognosis and therapeutic management. Pathologists have an important role in this evaluation. The methodologies have varied over time, from the evaluation of dimensions of metastatic burden to determination of the location of the tumour deposits within the lymph node to precise cell counting. However, no single method of sentinel lymph node tumour burden measurement can currently be used as a sole independent predictor of prognosis. The management approach to sentinel lymph node-positive patients has also evolved over time, with a more conservative approach recently recognised for selected cases. This review gives an overview of past and current status in the field with a glimpse into future directions based on prior experiences and clinical trials.


Assuntos
Linfadenopatia , Melanoma , Linfonodo Sentinela , Neoplasias Cutâneas , Humanos , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela/métodos , Excisão de Linfonodo/métodos , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Melanoma/patologia , Linfonodos/patologia , Prognóstico , Linfadenopatia/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
3.
Neurocrit Care ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062302

RESUMO

BACKGROUND: Neurocardiogenic injury is common after aneurysmal subarachnoid hemorrhage (aSAH) despite low prevalence of preexisting cardiac disease. Potential mechanisms include autonomic dysregulation due to excess catecholamines as well as systemic inflammation. Understanding how inflammation contributes to cardiac dysfunction may aid in identifying novel therapeutic strategies. Here, we investigated serum leukocytes as predictors of left ventricular systolic dysfunction in patients with aSAH. We also investigated increased cardiac macrophages in an animal model of SAH and whether immunomodulatory treatment could attenuate this inflammatory response. METHODS: We retrospectively analyzed 256 patients with aSAH admitted to University of Illinois Hospital between 2013 and 2019. Our inclusion criteria included patients with aSAH receiving an echocardiogram within 72 h of admission. Our primary outcome was echocardiographic evidence of systolic dysfunction. We performed multinomial regression and receiver operating curve analysis. We also used the endovascular perforation model of SAH in male Sprague-Dawley rats to assess for myocardial inflammation. Two days after surgery, hearts were collected and stained for the macrophage marker Iba-1. We compared the presence and morphology of macrophages in cardiac tissue isolated from SAH animals and sham controls treated with and without the immunomodulatory agent fingolimod. RESULTS: Of 256 patients with aSAH, 233 (91.0%) underwent echocardiography within 72 h of admission. Of 233, 81 (34.7%) had systolic dysfunction. Patients had baseline differences in the presence of hypertension, alcohol use, and admission Glasgow Coma Scale and Hunt-Hess score. On multivariable analysis, total leukocytes (odds ratio 1.312, p < 0.001), neutrophils (odds ratio 1.242, p = 0.012), and monocytes (odds ratio 6.112, p = 0.008) were independent predictors of reduced systolic function, whereas only monocytes (odds ratio 28.014, p = 0.030) predicted hyperdynamic function. Within the rodent heart, there were increased macrophages after SAH relative to controls, and this was attenuated by fingolimod treatment (p < 0.0001). CONCLUSIONS: Increased serum leukocytes are associated with abnormal left ventricular systolic function following aSAH. The strongest independent predictor of both reduced and hyperdynamic systolic function was increased monocytes. Increased cardiac macrophages after experimental SAH can also be targeted by using immunomodulatory drugs.

4.
Cleft Palate Craniofac J ; 60(10): 1199-1206, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35612863

RESUMO

This study aims to identify gender disparities within the subspecialty of craniofacial surgery as women surgeons remain underrepresented in academia and leadership, arenas heavily dictated by research productivity.All craniofacial articles published in 3 major research journals from 2000 to 2020 were reviewed and evaluated in 5-year increments.Information regarding author gender, authorship distribution, geographic origin, and publication type was collected. ANOVA, χ2, and logistic regression modeling were used for analysis.In total, there were 3684 articles with 15 206 total authors-3128 (20.6%) were women, including 665 (21.3%) first authors, 1980 (63.2%) middle authors, and 487 (15.7%) senior authors. Mean women authorship increased significantly from 2000 to 2020 (0.33 vs 1.22 P < .001) with corresponding significant increases in first and senior authorship (8.63% vs 27.02; 5.65% vs 16.13%; P < .001). Statistically significant trends across time were observed for first and senior authorships (P < .001). Women were more likely to publish original publications as first and senior authors (OR: 1.83, P < .001; OR: 1.37, P = .0012). Women were less likely to publish editorial articles (OR 0.6, P < .001). The United States ranked third in publication output by female first authors but was behind all regions except Africa for output by female senior authors.Although female authorship has increased significantly over the last 2 decades, women remain a minority within the craniofacial literature. Further research is needed to elicit the root of these disparities.


Assuntos
Autoria , Bibliometria , Humanos , Feminino , Estados Unidos , Masculino , Fatores Sexuais , Liderança , Modelos Logísticos
5.
Orbit ; : 1-9, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36661099

RESUMO

PURPOSE: Unexpected anesthesia-related complications are among the most feared outcomes of ambulatory surgery. One potential culprit is pseudocholinesterase deficiency, which most commonly presents with protracted apnea, necessitating prolonged mechanical ventilation. We report the first case of pseudocholinesterase deficiency in a Bengali person and the first systematic review of pseudocholinesterase deficiency in ophthalmology. This review analyzed the epidemiology, etiologies, presentation, evaluation, and treatment of pseudocholinesterase deficiency. METHODS: Searches were conducted in PubMed, Embase, and Medline through August of 2022 for publications related to pseudocholinesterase deficiency in ophthalmology. In total, 689 studies were screened by two independent reviewers with 26 full-text articles examined for inclusion eligibility. Nineteen studies were eligible and included in the final analysis. RESULTS: Of the 16 identified cases of pseudocholinesterase deficiency, nine (56%) were drug-induced, four (25%) were inherited deficiencies, and in one (6%) of the cases, the cause could not be determined. In two (13%) cases, pseudocholinesterase deficiency could not be confirmed or ruled out. The duration of post-operative apnea ranged from 10 minutes to 14 hours. Continued ventilatory support was the main treatment for all cases and all patients made a full recovery. CONCLUSIONS: Pseudocholinesterase deficiency is a rare, but potentially fatal, anesthetic complication that results in prolonged apnea, respiratory distress, and dependency on ventilators. Ophthalmologists should remain aware of this condition, especially when planning outpatient procedures, as ambulatory centers may have limited resources for managing prolonged post-operative complications.

6.
Ophthalmic Plast Reconstr Surg ; 38(5): 452-457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35323143

RESUMO

PURPOSE: To analyze the source and quality of oculoplastics-related content on TikTok, a popular social media platform. METHODS: Twenty-five oculoplastics-related hashtags were queried. The top 20 videos for each hashtag were included. The number of views, likes, comments, and shares were recorded for each video. Each video was also categorized by the account owner and by video content characteristics. A subanalysis of the educational videos was conducted using the mDISCERN, Patient Education Materials Assessment Tool, and modified MICI scores to assess video quality, understandability and actionability, and medical accuracy, respectively. RESULTS: The included 386 videos amassed 218,997,134 views, 15,033,220 likes, 148,099 comments, and 276,445 shares. Patients were the leading content creators (38.1%), followed by nonophthalmology MDs/DOs (25.6%), and oculoplastic surgeons/ophthalmologists (16.3%). Physician-created videos received more visibility than nonphysician-created videos (median of 23,600 views and 22 shares), though this did not reach statistical significance. However, oculoplastic surgeon-posted content received the lowest median views and shares. The video category that amassed the most views was "live procedure/surgeries," followed by "educational" and "patient experience." Subanalysis of 46 educational videos revealed physicians were the chief creators, accounting for 67.4% of all educational videos. Physician-created content demonstrated statistically significant better understandability and actionability, as measured by the Patient Education Materials Assessment Tool ( p = 0.0053). CONCLUSION: Physicians play an important role in disseminating evidence-based medicine on social media. While oculoplastics-related TikTok videos are gaining traction, additional research is needed to improve the visibility of oculoplastic-surgeon posted content.


Assuntos
Mídias Sociais , Humanos , Gravação em Vídeo
7.
J Craniofac Surg ; 33(5): 1400-1403, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35240671

RESUMO

INTRODUCTION: Recent advances in craniofacial surgery have occurred in conjunction with a global proliferation of research. Although previous studies have examined geographic publication trends, little is known about these trends in the craniofacial literature. METHODS: All craniofacial articles published from 2000 to 2020 in 3 premier craniofacial surgery journals were evaluated in 5-year increments. Geographic origin, manuscript type, and authorship characteristics were collected. Changes in publication output, geographic origin, and content were analyzed. RESULTS: In total 3864 articles were analyzed, with the United States (U.S.) (33.46%) accounting for the majority, followed by Asia (27.04%), the Middle East (16.23%), and Europe (14.65%). The proportion of articles from the U.S. decreased significantly in the in the 20-year span (48.28% versus 33.53%, P < 0.001), whereas those originating from Asia and the Middle East increased significantly (18.62% versus 31.41% and 10.34% versus 15.66%, respectively, P < 0.001). After stratifying and selecting for regions with the greatest changes in publication output, the authors observed significant trends for the number of original investigations from 2000 to 2020 in the U.S. (Odds Ratio [OR] 1 versus 2.4, P < 0.001) and in Asia (OR 1 versus 1.8, P = 0.0052). Additionally, a significant trend in editorial/correspondence publications originating in the U.S. (OR 1 versus 0.74, P = 0.0102), Europe (OR 1 versus 0.38, P = 0.0186), and Asia (OR 1 versus 0.48, P = 0.0051) was observed. CONCLUSIONS: Despite rising craniofacial publications over the past 2 decades, there has been a diminishing proportion originating from the U.S.


Assuntos
Autoria , Bibliometria , Ásia , Europa (Continente) , Humanos , Oriente Médio , Publicações Periódicas como Assunto , Estados Unidos
8.
J Stroke Cerebrovasc Dis ; 31(5): 106423, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35255288

RESUMO

OBJECTIVES: Aneurysmal subarachnoid hemorrhage (aSAH) accounts for 5% of strokes but results in significant morbidity and mortality. In addition to systemic inflammation, up to half of patients develop cardiac injury; however, the relationship between systemic inflammation and cardiac injury after aSAH is unknown. We investigated changes in leukocyte counts in relation to cardiac dysfunction MATERIALS AND METHODS: We reviewed the records of consecutive patients with SAH at our large academic medical referral center. The inclusion criteria were aSAH and available cardiac troponin I (cTnI) levels within 48 h of admission. The primary outcome was cardiac injury, defined as cTnI ≥0.04 ng/mL (lab reference range 0.01-0.03 ng/mL). We compared baseline characteristics, including serum leukocyte counts and performed univariable and multivariable logistic regression analysis to determine whether changes in leukocyte subpopulations predict cardiac injury. RESULTS: Of 288 SAH patients, 250 met inclusion criteria. Of these, 116 (46.4%) had elevated cTnI. In univariable analysis, total leukocyte count (p < 0.001), absolute neutrophil count (ANC, p < 0.001), and absolute monocyte count (p = 0.013), were associated with elevated cTnI. in multivariable analysis, total leukocyte count (OR=1.079, p = 0.037) and ANC (OR=1.081, p = 0.044) remained predictors of elevated cTnI. Adjusted ANC distinguishes between aSAH patients with normal and elevated TnI (area under the curve=0.766, p < 0.001) with specificity of 89.2%. CONCLUSIONS: Elevated total leukocytes and ANC are independently associated with cardiac injury in aSAH. Systemic inflammatory responses after aSAH may play a role in cardiac dysfunction, warranting additional studies to further characterize how cardiac inflammation after aSAH drives subsequent morbidity and mortality.


Assuntos
Cardiopatias , Hemorragia Subaracnóidea , Biomarcadores , Cardiopatias/complicações , Cardiopatias/etiologia , Humanos , Inflamação/complicações , Neutrófilos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/diagnóstico , Troponina I
9.
Qual Life Res ; 30(11): 3189-3197, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32909161

RESUMO

PURPOSE: Tracking patient-reported outcomes (PROs) and quality-of-life response rates is essential for clinical trials. Historically, rates are monitored through scheduled reports, which can require gathering, merging, and cleaning data from multiple databases. At the end of this process, if gaps are found, new data are entered and the cycle repeats, leaving a trail of reports that are not up-to-date or immediately accessible to the investigator. The financial and person-hour cost of utilizing clinical research staff for this purpose is impractical. Online dashboards are continuously updated to monitor data, providing on-demand access to promote successful research. METHODS: Dashboard implementation utilizes R, an open-source statistical programming language, RMarkdown, a markup language, Flexdashboard, which creates structural elements, and Shiny, allowing investigators the ability to interact with data within the dashboard. By leveraging these four elements, powerful, cost-effective interactive dashboards can be built. RESULTS: Numerous dashboards have been utilized to identify potentially missing data and increase protocol adherence. Immediate patient consultation can occur to retrieve protocol-related forms, reducing research staff and patient burden while improving trial effectiveness. Dashboards can monitor PROs, enrollment, demographics, toxicity, and biomarker data, clinical outcomes, and implemented predictive models, creating a single hub for on-demand clinical trial monitoring. CONCLUSION: By employing a set of freely available tools, the burden of utilizing study staff to continuously monitor trials is greatly reduced. These tools allow users to rapidly build and deploy dynamic dashboards capable of meeting the research needs of any investigator while limiting missing data through simplified monitoring of protocol adherence.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Bases de Dados Factuais , Humanos , Qualidade de Vida/psicologia
10.
Pediatr Surg Int ; 37(11): 1505-1513, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34398295

RESUMO

PURPOSE: The aim of the study was to understand the use of Extracorporeal Membrane Oxygenation (ECMO) in congenital diaphragmatic hernia (CDH) and its outcomes. METHODS: The 2016 Kid's Inpatient Database (KID) obtained from the national Healthcare Cost and Utilization Project (HCUP) was used to obtain CDH birth, demographic, and outcome data associated with ECMO use. Categorical variables were analyzed and odds ratios (OR) with 95% confidence intervals (CI) are reported for variables found to have significance (p < 0.05). Appropriate regressions were used for comparing categorical and continuous data using SPSS 25 for Macintosh. RESULTS: The database contained 1189 cases of CDH, of which 133 (11.2%) received ECMO. The overall mortality of neonates with CDH was 18.9% (225/1189). Newborns with CDH on ECMO had a survival of 46% (61/133) compared to 85.5% without ECMO (903/1056) (OR 6.966, p < 0.001, 95% CI 4.756-10.204). ECMO increased length of stay from 24.6 to 69.8 days (OR 2.834, p < 0.001, 95% CI 2.768-2.903) and average cost from $375,002.20 to $1641,586.83 (OR 4.378, p < 0.001, 95% CI 3.341-5.735). CONCLUSIONS: Increased length of stay, costs, and outcomes with ECMO use in CDH should prompt an examination of criteria necessitating ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas , Demografia , Hérnias Diafragmáticas Congênitas/epidemiologia , Hérnias Diafragmáticas Congênitas/terapia , Humanos , Recém-Nascido , Razão de Chances , Estudos Retrospectivos
11.
Nat Immunol ; 9(8): 937-44, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18587399

RESUMO

The parasite Toxoplasma gondii replicates in a specialized intracellular vacuole and causes disease in many species. Protection from toxoplasmosis is mediated by CD8(+) T cells, but the T. gondii antigens and host genes required for eliciting protective immunity are poorly defined. Here we identified GRA6, a polymorphic protein secreted in the parasitophorous vacuole, as the source of the immunodominant and protective decapeptide HF10 presented by the H-2L(d) major histocompatibility complex class I molecule. Presentation of the HF10-H-2L(d) ligand required proteolysis by ERAAP, the endoplasmic reticulum aminopeptidase associated with antigen processing. Consequently, expansion of protective CD8(+) T cell populations was impaired in T. gondii-infected ERAAP-deficient mice, which were more susceptible to toxoplasmosis. Thus, endoplasmic reticulum proteolysis is critical for eliciting protective immunity to a vacuolar parasite.


Assuntos
Antígenos de Protozoários/metabolismo , Retículo Endoplasmático/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Leucil Aminopeptidase/deficiência , Proteínas de Protozoários/metabolismo , Toxoplasma/imunologia , Toxoplasmose/imunologia , Animais , Apresentação de Antígeno , Leucil Aminopeptidase/imunologia , Leucil Aminopeptidase/metabolismo , Camundongos , Toxoplasma/fisiologia , Vacúolos/imunologia
13.
Front Psychiatry ; 14: 1179677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151973

RESUMO

The goal of this review was to provide an overview of how solitude has been operationally defined and measured since the year 2000 in psychological studies of children, adolescents, and emerging adults. After applying exclusionary criteria, our review of the extant literature identified n = 19 empirical studies, which we grouped into three broad methodological categories: (1) experiments/manipulations (n = 5); (2) retrospective reports (n = 7); and (3) experience sampling measures (experience sampling methodology; n = 7). A review of these studies indicated considerable variation in how solitude is operationalized and measured. There is also a notable lack of studies measuring solitude in childhood. Implications for 'what matters' when assessing solitude are discussed, and we provide a series of suggestions for helping this research area move forward.

14.
J Plast Reconstr Aesthet Surg ; 84: 214-222, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37339546

RESUMO

PURPOSE: Social media platforms are popular sources of medical information but may harbor harmful misinformation. This study aims to evaluate the effect of TikTok on the transgender population, which may be more likely to seek information from non-traditional sources because of high medical mistrust. METHODS: Twenty gender affirmation related hashtags were queried, with the top 25 videos per hashtag included for analysis. Videos were categorized based on the content and creator. Variables included likes, comments, shares, and video views. All "educational" videos were analyzed for reliability of information using a modified DISCERN (mDISCERN) score and the Patient Education Materials Assessment Tool (PMAT). Kruskal-Wallis H tests, Mann-Whitney U tests, and simple linear regression models were used in analysis. RESULTS: A total of 429 videos amassed 571,434,231 views, 108,050,498 likes, 2,151,572 comments, and 190,9744 shares. Patients were the majority of content creators (74.88%), with patient experiences being the majority of videos (36.07%). Non-physician creators had significantly higher likes and comments when compared to physicians (6185 vs. 1645, p = 0.028; 108 vs. 47, p = 0.016 respectively). Sixty "educational" videos were included in information reliability analysis. There were no significant differences between video characteristics of different content creators, even after stratifying according to physician status. Significant differences were observed in the reliability of information according to PMAT and mDISCERN scores, with physician created videos being significantly higher rated than non-physician created videos (0.90 vs. 0.84, p < 0.001; 3 vs. 2, p < 0.001, respectively). CONCLUSION: Lower quality information is associated with non-physician content creators. We encourage physicians to be continuously involved in creating quality information on TikTok.


Assuntos
Mídias Sociais , Pessoas Transgênero , Humanos , Reprodutibilidade dos Testes , Confiança , Escolaridade , Gravação em Vídeo
15.
3D Print Addit Manuf ; 10(1): 1-14, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36852265

RESUMO

Hygromorphic smart structures are advantageous as passively actuated systems for generating movement, with applications ranging from weather-responsive architectural building skins to adaptive wearables and microrobotics. Four-dimensional (4D) printing is a valuable method for multiscale fabrication and physical programming of such structures. However, material limitations in terms of printability, responsiveness, and mechanical properties are major bottlenecks in achieving reliable and repeatable humidity-responsive actuation. We propose a codesign method for 4D printing hygromorphic structures through fused filament fabrication, incorporating parallel development of (1) biobased cellulose-filled filaments with varying stiffness and hygroresponsiveness, and (2) designed mesoscale structuring in printed elements. We first describe the design of a pallet of filaments produced by compounding cellulose powder in mass ratios of 0-30% within two matrix polymers with high and low stiffness. We then present the design, fabrication, and testing of a series of 4D-printed prototypes tuned to change shape, that is, open and close, in response to relative humidity (RH). The structures can fully transform in conditions of 35-90% RH, which corresponds to naturally occurring shifts in RH in daily and seasonal weather cycles. Furthermore, their motion is fast (within the range of minutes), fully reversible, and repeatable in numerous cycles. These results open new opportunities for the utilization of 4D printing and natural resources for the development of functional humidity-responsive smart structures.

16.
Biomimetics (Basel) ; 8(2)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37366828

RESUMO

Extrusion-based 4D-printing, which is an emerging field within additive manufacturing, has enabled the technical transfer of bioinspired self-shaping mechanisms by emulating the functional morphology of motile plant structures (e.g., leaves, petals, capsules). However, restricted by the layer-by-layer extrusion process, much of the resulting works are simplified abstractions of the pinecone scale's bilayer structure. This paper presents a new method of 4D-printing by rotating the printed axis of the bilayers, which enables the design and fabrication of self-shaping monomaterial systems in cross sections. This research introduces a computational workflow for programming, simulating, and 4D-printing differentiated cross sections with multilayered mechanical properties. Taking inspiration from the large-flowered butterwort (Pinguicula grandiflora), which shows the formation of depressions on its trap leaves upon contact with prey, we investigate the depression formation of bioinspired 4D-printed test structures by varying each depth layer. Cross-sectional 4D-printing expands the design space of bioinspired bilayer mechanisms beyond the XY plane, allows more control in tuning their self-shaping properties, and paves the way toward large-scale 4D-printed structures with high-resolution programmability.

17.
Biochem Biophys Res Commun ; 426(4): 544-50, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-22982316

RESUMO

Treatment of mesenchymal stem cells (MSCs) with fibroblast growth factor 2 (FGF-2) during monolayer expansion leads to increased expression of cartilage-related molecules during subsequent pellet chondrogenesis. This may be due to faster differentiation and/or a durable change in phenotype. In order to evaluate changes over time, we assessed chondrogenesis of human MSCs at early and late time points during pellet culture using real-time PCR, measurement of glycosaminoglycan accumulation, and histology. Marked enhancement of chondrogenesis was seen early compared to controls. However, the differences from controls in gene expression dramatically diminished over time. Depending on conditions, increases in glycosaminoglycan accumulation were maintained. These results suggest that FGF-2 can enhance the kinetics of MSC chondrogenesis, leading to early differentiation, possibly by a priming mechanism.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células Cultivadas , Condrogênese/genética , Colágeno Tipo I/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia
18.
Exp Brain Res ; 221(3): 329-35, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22821076

RESUMO

The sleep-wake cycle is a major determinant of locomotor activity in humans, and the neural and physiological processes necessary for optimum postural control may be impaired by an extension of the wake period into habitual sleep time. There is growing evidence for such a contribution from sleep-related factors, but great inconsistency in the methods used to assess this contribution, particularly in control for circadian phase position. Postural control was assessed at hourly intervals across 14 h of extended wake in nine young adult participants. Force plate parameters of medio-lateral and anterior-posterior sway, centre of pressure (CoP) trace length, area, and velocity were assessed with eyes open and eyes closed over 3-min periods. A standard measure of psychomotor vigilance was assessed concurrently under constant routine conditions. After controlling for individual differences in circadian phase position, a significant effect of extended wake was found for anterior-posterior sway and for psychomotor vigilance. These data suggest that extended wake may increase the risk of a fall or other consequences of impaired postural control.


Assuntos
Ritmo Circadiano/fisiologia , Equilíbrio Postural/fisiologia , Desempenho Psicomotor/fisiologia , Fases do Sono/fisiologia , Vigília/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
19.
J Pediatr Surg ; 57(2): 278-283, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34952693

RESUMO

AIM OF STUDY: Firearm injuries are the second leading cause of injury-related death in the USA in children less than 18. We compared overall and intent-specific firearm hospitalizations across age group and race to understand recent trends. METHODS: A retrospective cohort of 20,083 children from the national trauma data bank involved in incidences of firearm discharges from 2013 to 2017 was divided by race, discharge intent, gun type, and four age groups: infants (ages 0-2), toddlers (3-6), children (7-12), and adolescents (13-18). Discharge intent and gun type were determined by ICD-9-CM and ICD-10-CM External Causes of Injury codes. Injury severity score (ISS), hospital discharge disposition, and length of stay (LOS) were used as predictors for morbidity and mortality. RESULTS: From 2013 to 2017, there were on an average 4016 firearm injuries reported to the NTDB (n = 20,083). 71% (n = 14,313) of the incidents were assaults. Victims who identified as African American and Caucasian made up 60% (n = 11,890) and 26% (n = 5162) of the total victims, respectively, and were predominantly male (86%, n = 17,202). Victims who identified as Caucasian made up 70% of suicides (n = 819), while African Americans made up 70% of assaults (n = 9733). 87% (n = 17,525) of the patient population were adolescents. The number of accidental firearm discharges compared to firearm assaults was greater for toddlers, while the opposite was true for infants, children, and adolescents. Average LOS by age group varied each year, though children had the highest total average LOS.  Average ISS was highest for infants and adolescents (11.5 and 10.4) and American Indians and Caucasians (10.1 and 11.1). Overall mortality rate was 6% (n = 1220) and had no significant differences between years. Mortality rate was highest for infants (7%, n = 25). CONCLUSIONS: Adolescent males and African Americans were disproportionately affected by overall and assault-specific firearm discharges. Firearm injury prevention legislation is critical to prevent these injures.


Assuntos
Armas de Fogo , Suicídio , Ferimentos por Arma de Fogo , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Escala de Gravidade do Ferimento , Masculino , Estudos Retrospectivos , Estados Unidos/epidemiologia , Ferimentos por Arma de Fogo/epidemiologia
20.
Front Oncol ; 12: 889223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747831

RESUMO

Spitz tumors represent a distinct subtype of melanocytic lesions with characteristic histopathologic features, some of which are overlapping with melanoma. More common in the pediatric and younger population, they can be clinically suspected by recognizing specific patterns on dermatoscopic examination, and several subtypes have been described. We now classify these lesions into benign Spitz nevi, intermediate lesions identified as "atypical Spitz tumors" (or Spitz melanocytoma) and malignant Spitz melanoma. More recently a large body of work has uncovered the molecular underpinning of Spitz tumors, including mutations in the HRAS gene and several gene fusions involving several protein kinases. Here we present an overarching view of our current knowledge and understanding of Spitz tumors, detailing clinical, histopathological and molecular features characteristic of these lesions.

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