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Information sharing influences which messages spread and shape beliefs, behavior, and culture. In a preregistered neuroimaging study conducted in the United States and the Netherlands, we demonstrate replicability, predictive validity, and generalizability of a brain-based prediction model of information sharing. Replicating findings in Scholz et al., Proc. Natl. Acad. Sci. U.S.A. 114, 2881-2886 (2017), self-, social-, and value-related neural signals in a group of individuals tracked the population sharing of US news articles. Preregistered brain-based prediction models trained on Scholz et al. (2017) data proved generalizable to the new data, explaining more variance in population sharing than self-report ratings alone. Neural signals (versus self-reports) more reliably predicted sharing cross-culturally, suggesting that they capture more universal psychological mechanisms underlying sharing behavior. These findings highlight key neurocognitive foundations of sharing, suggest potential target mechanisms for interventions to increase message effectiveness, and advance brain-as-predictor research.
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Mapeamento Encefálico , Encéfalo , Humanos , Estados Unidos , Mapeamento Encefálico/métodos , Disseminação de Informação , Neuroimagem , CabeçaRESUMO
PURPOSE: To systematically review the current evidence in the literature to compare return to play following arthroscopic Bankart repair versus open Latarjet procedure for the treatment of anterior shoulder instability. METHODS: A literature search was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Comparative studies reporting return to play following arthroscopic Bankart repair versus open Latarjet procedure were included. Return to play was compared, with all statistical analysis performed using Review Manager, Version 5.3. RESULTS: Nine studies with 1,242 patients (mean age: 15-30 years) were included. The rate of return to play was 61% to 94.1% among those undergoing arthroscopic Bankart repair and 72% to 96.8% in those undergoing an open Latarjet procedure. Two studies (Bessiere et al. and Zimmerman et al.) found a significant difference in favor of the Latarjet procedure (P < .05 for both, I2 = 37%). The rate of return to play at preinjury level was 9% to 83.8% among those undergoing arthroscopic Bankart repair and 19.4% to 80.6% in those undergoing an open Latarjet procedure, with no study finding a significant difference (P > .05 for all, I2 = 0%). The mean time of return to play was 5.4 to 7.3 months among those undergoing arthroscopic Bankart repair and 5.5 to 6.2 months in those undergoing an open Latarjet procedure, with no study finding a significant difference (P > .05 for all, I2 = 39%). CONCLUSIONS: Overall, the majority of studies showed no significant difference in rates of return to play or timing following arthroscopic Bankart repair or open Latarjet procedure. Furthermore, no study has found a significant difference in rate of return to play at pre-injury level, or rate of return to play among collision athletes. LEVEL OF EVIDENCE: Level III, systematic review of Level I-III studies.
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Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Humanos , Adolescente , Adulto Jovem , Adulto , Luxação do Ombro/cirurgia , Articulação do Ombro/cirurgia , Volta ao Esporte , Instabilidade Articular/cirurgia , Estudos Retrospectivos , Recidiva , Artroscopia/métodosRESUMO
The thiamine diphosphate (ThDP)-binding motif, characterized by the canonical GDG(X)24-27N sequence, is highly conserved among ThDP-dependent enzymes. We investigated a ThDP-dependent lyase (JanthE from Janthinobacterium sp. HH01) with an unusual cysteine (C458) replacing the first glycine of this motif. JanthE exhibits a high substrate promiscuity and accepts long aliphatic α-keto acids as donors. Sterically hindered aromatic aldehydes or non-activated ketones are acceptor substrates, giving access to a variety of secondary and tertiary alcohols as carboligation products. The crystal structure solved at a resolution of 1.9â Å reveals that C458 is not primarily involved in cofactor binding as previously thought for the canonical glycine. Instead, it coordinates methionine 406, thus ensuring the integrity of the active site and the enzyme activity. In addition, we have determined the long-sought genuine tetrahedral intermediates formed with pyruvate and 2-oxobutyrate in the pre-decarboxylation states and deciphered the atomic details for their stabilization in the active site. Collectively, we unravel an unexpected role for the first residue of the ThDP-binding motif and unlock a family of lyases that can perform valuable carboligation reactions.
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Tiamina Pirofosfato , Tiamina Pirofosfato/metabolismo , Tiamina Pirofosfato/química , Liases/metabolismo , Liases/química , Motivos de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Especificidade por Substrato , Modelos MolecularesRESUMO
INTRODUCTION: Existing research has established a correlation between post-traumatic mental health conditions, including anxiety and depression, and various aspects of recovery, such as pain exacerbations, reduced functional recovery, and lowered patient satisfaction. However, the influence of pre-existing mental health conditions on orthopaedic trauma outcomes has not been thoroughly investigated. The objective of this study was to systematically review literature addressing the association between pre-existing mental health conditions and patient outcomes following surgical interventions for lower extremity fractures in non-geriatric populations. METHODS: A systematic literature review was conducted using Medline, Embase, and Scopus databases following PRISMA-ScR guidelines to select studies that examined lower extremity orthopaedic trauma outcomes in relation to pre-existing mental health conditions. Studies that evaluated patients with surgically treated lower extremity fractures and a history of mental health conditions such as anxiety, depression, or mood disorders were included. Studies with a mean patient age above 65 years of age were excluded to focus on non-geriatric injury patterns. RESULTS: The systematic review identified 12 studies investigating the relationship between surgical outcomes of orthopaedic lower extremity fractures and pre-existing mental health disorders in non-geriatric populations. Studies included patients with pelvis, femur, tibia, and ankle fractures. A majority (83%) of these studies demonstrated that patients with pre-existing mental health diagnoses had inferior functional outcomes, heightened pain levels, or an increase in postoperative complications. DISCUSSION: The presence of pre-existing mental health conditions, particularly anxiety and depression, may predispose orthopaedic trauma patients to an elevated risk of suboptimal functional outcomes, increased pain, or complications after surgical intervention for lower extremity fractures. Future research should focus on interventions that mitigate the impact of mental health conditions on orthopaedic outcomes and patient wellness in this population.
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Fraturas do Tornozelo , Traumatismos da Perna , Ortopedia , Humanos , Idoso , Saúde Mental , Traumatismos da Perna/complicações , Traumatismos da Perna/cirurgia , Extremidade Inferior/cirurgia , Extremidade Inferior/lesões , DorRESUMO
Brown adipose tissue (BAT) consists of highly metabolically active adipocytes that catabolize nutrients to produce heat. Playing an active role in triacylglycerol (TAG) clearance, research has shown that dietary fatty acids can modulate the TAG chemistry deposition in BAT after weeks-long dietary intervention, similar to what has been shown in white adipose tissue (WAT). Our objective was to compare the influence of sustained, nonchronic dietary intervention (a 1-week interval) on WAT and interscapular BAT lipid metabolism and deposition in situ. We use quantitative, label-free chemical microscopy to show that 1 week of high fat diet (HFD) intervention results in dramatically larger lipid droplet (LD) growth in BAT (and liver) compared to LD growth in inguinal WAT (IWAT). Moreover, BAT showed lipid remodeling as increased unsaturated TAGs in LDs, resembling the dietary lipid composition, while WAT (and liver) did not show lipid remodeling on this time scale. Concurrently, expression of genes involved in lipid metabolism, particularly desaturases, was reduced in BAT and liver from HFD-fed mice after 1 week. Our data show that BAT lipid chemistry remodels exceptionally fast to dietary lipid intervention compared WAT, which further points towards a role in TAG clearance.
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Tecido Adiposo Marrom , Dieta Hiperlipídica , Camundongos , Animais , Tecido Adiposo Marrom/metabolismo , Dieta Hiperlipídica/efeitos adversos , Microscopia , Tecido Adiposo Branco/metabolismo , Fígado/metabolismo , Gorduras na Dieta , Tecido Adiposo , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Cigarette smoking continues to be a leading cause of preventable deaths in the USA, in part because the USA has not adopted the WHO Framework Convention on Tobacco Control. One way the tobacco industry counteracts tobacco control policies is by heavily advertising cigarettes at the point of sale in retailers (eg, at the cash register) and by offering discounts on cigarettes. DESIGN: A within-subject experimental design with adults who smoke cigarettes daily (n=281) investigated whether: (1) exposure to images of cigarette promotions in an online experiment is associated with greater cigarette craving relative to viewing images of non-smoking cues, and (2) if exposure to images of point-of-sale cigarette promotions with a discount (vs without) increases cigarette craving. The study also examined how participants' subjective social status (compared with others in the USA) relates to cigarette craving after exposure to images of cigarette promotions with and without a discount. RESULTS: In an online experiment, exposure to images of smoking cues, including point-of-sale cigarette promotions, elicited greater craving relative to non-smoking cues (all p<0.001). In addition, images of promotions with a discount elicited higher levels of craving compared with those without a discount (b=0.09, p=0.001). Although participants with a higher (vs lower) subjective social status craved cigarettes less overall (b=-0.12, p=0.012), there was no difference in their craving between images of promotions with and without a discount, while craving was higher for images of promotions with a discount than without for participants with higher subjective social status (b=0.06, p=0.021). CONCLUSION: Viewing images of point-of-sale cigarette promotions can causally increase cravings to smoke, which may also apply to real-world retail settings that display cigarette promotions. Restricting point-of-sale promotions generally, and discounts specifically, could help reduce cigarette smoking and address tobacco use disparities in the USA.
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BACKGROUND: Disordered eating is common but underrecognized in people with obesity and the relationship of food insecurity, mood, and binge-spectrum eating disorders has not been well addressed in samples with higher weight. Young adults are particularly vulnerable to developing disordered eating. OBJECTIVE: The purpose of this study was to compare the prevalence of food insecurity, depressive symptoms, anxiety, and loneliness among young adults (aged 18-35 years) who screened positive for binge-spectrum eating disorders (i.e., binge eating disorder and bulimia nervosa), those with subthreshold forms of these disorders, and individuals who did not screen positive for these conditions. METHOD: This was a cross-sectional study of young adults with a self-reported body mass index ≥30 kg/m2 from the United States who were recruited online. Participants (N = 1,331; M ± SD age = 28.0 ± 3.4 years; body mass index [BMI] = 36.5 ± 6.2 kg/m2; 73.9% male; 56.3% White) completed surveys that evaluated disordered eating behaviors, food insecurity, mood, and lifestyle factors. RESULTS: In the sample, 8.0% of participants screened positive for binge-spectrum eating disorder and 16.0% had probable subthreshold symptoms. Higher depressive symptoms (odds ratio [OR] = 1.11, 95% confidence interval [CI] = [1.03, 1.20], p = .01), perceived stress (OR = 1.13, 95% CI = [1.07, 1.19], p < .001), and food insecurity scores (OR = 1.12, 95% CI = [1.03, 1.21], p = .01) were associated with an increased likelihood of threshold binge-spectrum eating disorders. CONCLUSION: People with disordered eating should also be evaluated for mood disorders and food insecurity and vice versa. Further research is needed to evaluate interventions that address food insecurity and mood disorders, which may help to decrease disordered eating.
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PURPOSE: Interfragmentary strain influences whether a fracture will undergo direct and indirect fracture healing. Orthopedic trauma surgeons modulate strain and create optimal biomechanical environments for specific fracture patterns using fixation constructs. However, objective intraoperative interfragmentary strain measurement does not currently inform fixation strategy in common practice. This review identifies potential methods and technologies to enable intraoperative strain measurement for guiding optimal fracture fixation strategies. METHODS: PubMed, Scopus, and Web of Science were methodologically queried for manuscripts containing terms related to "bone fracture," "strain," "measurement," and "intraoperative." Manuscripts were systematically screened for relevance and adjudicated by three reviewers. Relevant articles describing methods to measure interfragmentary strain intraoperatively were summarized. RESULTS: After removing duplicates, 1404 records were screened initially. There were 49 manuscripts meeting criteria for in-depth review. Of these, four reports were included in this study that described methods applicable to measuring interfragmentary strain intraoperatively. Two of these reports described a method using instrumented staples, one described optical tracking of Kirschner wires, and one described using a digital linear variable displacement transducer with a custom external fixator. CONCLUSION: The four reports identified by this review describe potential methods to quantify interfragmentary strain after fixation. However, further studies are needed to confirm the precision and accuracy of these measurements across a range of fractures and fixation methods. Additionally, described methods require the insertion and likely removal of additional implants into the bone. Ideally, innovations that measure interfragmentary strain intraoperatively would provide dynamic biomechanical feedback for the surgeon to proactively modulate construct stability.
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Fixação Interna de Fraturas , Fraturas Ósseas , Humanos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Fios Ortopédicos , Consolidação da Fratura , Tomada de Decisões , Fenômenos BiomecânicosRESUMO
Simpson-Golabi-Behmel syndrome (SGBS) is a rare X-linked condition characterized by pre and postnatal overgrowth with visceral and skeletal abnormalities. The syndrome is caused mainly by mutations in the X-linked gene GPC3. Clinical presentation of SGBS in affected males is well defined, but there is a lack of knowledge about affected females, with very few reported cases. In total, eight female carriers with clinical expression of SGBS have been reported to date. In the present report, we describe the ninth patient and her family history. The interesting features of our female patient are the Wilms' tumor and the transfontanelar ultrasound findings. The patient's older sister, carrier of the same mutation, has minor facial dysmorphisms but no congenital anomalies and so far, no further clinical findings, as well as her mother and grandmother. There is a lesson to be learned from these rare cases, namely that SGBS may have a significant clinical expression in females, and therefore, screening should be considered in all patients with SGBS regardless of the sex or phenotypic severity.
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Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Estudos de Associação Genética , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/genética , Predisposição Genética para Doença , Gigantismo/diagnóstico , Gigantismo/genética , Glipicanas/genética , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Mutação , Fenótipo , Alelos , Biópsia , Análise Mutacional de DNA , Fácies , Feminino , Genes Ligados ao Cromossomo X , Estudos de Associação Genética/métodos , Genótipo , Humanos , Lactente , Masculino , Linhagem , Inativação do Cromossomo XRESUMO
AIMS/HYPOTHESIS: Intramyocellular lipid (IMCL) content associates with development of insulin resistance, albeit not in insulin-sensitive endurance-trained athletes (trained). Qualitative and spatial differences in muscle lipid composition may underlie this so-called athlete's paradox. Here we studied triacylglycerol (TAG) composition of individual myocellular lipid droplets (LDs) in trained individuals and individuals with type 2 diabetes mellitus. METHODS: Trained ([Formula: see text] 71.0 ± 1.6 ml O2 [kg lean body mass (LBM)]-1 min-1), normoglycaemic (fasting glucose 5.1 ± 0.1 mmol/l) individuals and untrained ([Formula: see text] 36.8 ± 1.5 ml O2 [kg LBM]-1 min-1) individuals with type 2 diabetes (fasting glucose 7.4 ± 0.5 mmol/l), with similar IMCL content (3.5 ± 0.7% vs 2.5 ± 0.3%, p = 0.241), but at opposite ends of the insulin sensitivity spectrum (glucose infusion rate 93.8 ± 6.6 vs 25.7 ± 5.3 µmol [kg LBM]-1 min-1 for trained individuals and those with type 2 diabetes, respectively) were included from our database in the present study. We applied in situ label-free broadband coherent anti-Stokes Raman scattering (CARS) microscopy to sections from skeletal muscle biopsies to measure TAG acyl chain length and saturation of myocellular LDs. This approach uniquely permits examination of individual LDs in their native environment, in a fibre-type-specific manner, taking into account LD size and subcellular location. RESULTS: Despite a significant difference in insulin sensitivity, we observed remarkably similar acyl chain length and saturation in trained and type 2 diabetic individuals (chain length: 18.12 ± 0.61 vs 18.36 ± 0.43 number of carbons; saturation: 0.37 ± 0.05 vs 0.38 ± 0.06 number of C=C bonds). Longer acyl chains or higher saturation (lower C=C number) could be detected in subpopulations of LDs, i.e. large LDs (chain length: 18.11 ± 0.48 vs 18.63 ± 0.57 carbon number) and subsarcolemmal LDs (saturation: 0.34 ± 0.02 vs 0.36 ± 0.04 C=C number), which are more abundant in individuals with type 2 diabetes. CONCLUSIONS/INTERPRETATION: In contrast to reports of profound differences in the lipid composition of lipids extracted from skeletal muscle from trained and type 2 diabetic individuals, our in situ, LD-specific approach detected only modest differences in TAG composition in LD subpopulations, which were dependent on LD size and subcellular location. If, and to what extent, these modest differences can impact insulin sensitivity remains to be elucidated. Graphical abstract.
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Diabetes Mellitus Tipo 2/sangue , Triglicerídeos/sangue , Adulto , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Gotículas Lipídicas , Metabolismo dos Lipídeos/fisiologia , Adulto JovemRESUMO
ß-Adrenergic stimulation of adipose tissue increases mitochondrial density and activity (browning) that are associated with improved whole-body metabolism. Whereas chronically elevated levels of reactive oxygen species (ROS) in adipose tissue contribute to insulin resistance, transient ROS elevation stimulates physiological processes such as adipogenesis. Here, using a combination of biochemical and cell and molecular biology-based approaches, we studied whether ROS or antioxidant treatment affects ß3-adrenergic receptor (ß3-AR) stimulation-induced adipose tissue browning. We found that ß3-AR stimulation increases ROS levels in cultured adipocytes, but, unexpectedly, pretreatment with different antioxidants (N-acetylcysteine, vitamin E, or GSH ethyl ester) did not prevent this ROS increase. Using fluorescent probes, we discovered that the antioxidant treatments instead enhanced ß3-AR stimulation-induced mitochondrial ROS production. This pro-oxidant effect of antioxidants was, even in the absence of ß3-AR stimulation, associated with decreased oxygen consumption and increased lactate production in adipocytes. We observed similar antioxidant effects in WT mice: N-acetylcysteine blunted ß3-AR stimulation-induced browning of white adipose tissue and reduced mitochondrial activity in brown adipose tissue even in the absence of ß3-AR stimulation. Furthermore, N-acetylcysteine increased the levels of peroxiredoxin 3 and superoxide dismutase 2 in adipose tissue, indicating increased mitochondrial oxidative stress. We interpret this negative impact of antioxidants on oxygen consumption in vitro and adipose tissue browning in vivo as essential adaptations that prevent a further increase in mitochondrial ROS production. In summary, these results suggest that chronic antioxidant supplementation can produce a paradoxical increase in oxidative stress associated with mitochondrial dysfunction in adipocytes.
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Acetilcisteína/farmacologia , Adipócitos Marrons/metabolismo , Antioxidantes/farmacologia , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células 3T3-L1 , Adipócitos Marrons/fisiologia , Animais , Ácido Láctico/metabolismo , Masculino , Camundongos , Mitocôndrias/patologia , Receptores Adrenérgicos beta 3/metabolismoRESUMO
Lipid droplets (LDs), present in many cell types, are highly dynamic organelles that store neutral lipids, primarily triacylglycerols (TAGs). With the discovery of new LD functions (e.g., in immune response, protein clearage, and occurrence with disease), new methods to study LD chemical composition in situ are necessary. We present an approach for in situ, quantitative TAG analysis using label-free, coherent Raman microscopy that allows deciphering LD TAG composition in different biochemically complex samples with submicrometer spatial resolution. Employing a set of standard TAGs, we generate a spectral training matrix capturing the variation caused in Raman-like spectra by TAG backbone, chain length, and number of double bonds per chain, as well as the presence of proteins or other diluting molecules. Comparing our fitting approach to gas chromatography measurements for mixtures of standard TAGs and food oils, we find the root mean-square error for the prediction of TAG chemistry to be 0.69 CH2 and 0.15 #C=C. When progressing to more complex samples such as oil emulsions and LDs in various eukaryotic cells, we find good agreement with bulk gas chromatography measurements. For differentiated adipocytes, we find a significant increase in the number of double bonds in small LDs (below 2 µm in diameter) compared to large LDs (above 2 µm in diameter). Coupled with a relatively limited sample preparation requirement, this approach should enable rapid and accurate TAG LD analysis for a variety of cell biology and technological applications.
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Microscopia , Análise Espectral Raman , Triglicerídeos/química , Triglicerídeos/metabolismo , Animais , Linhagem Celular , Humanos , Gotículas Lipídicas/metabolismo , CamundongosRESUMO
Adiponectin is a hormone secreted from white adipocytes and takes part in the regulation of several metabolic processes. Although the pathophysiological importance of adiponectin has been thoroughly investigated, the mechanisms controlling its release are only partly understood. We have recently shown that adiponectin is secreted via regulated exocytosis of adiponectin-containing vesicles, that adiponectin exocytosis is stimulated by cAMP-dependent mechanisms, and that Ca2+ and ATP augment the cAMP-triggered secretion. However, much remains to be discovered regarding the molecular and cellular regulation of adiponectin release. Here, we have used mathematical modeling to extract detailed information contained within our previously obtained high-resolution patch-clamp time-resolved capacitance recordings to produce the first model of adiponectin exocytosis/secretion that combines all mechanistic knowledge deduced from electrophysiological experimental series. This model demonstrates that our previous understanding of the role of intracellular ATP in the control of adiponectin exocytosis needs to be revised to include an additional ATP-dependent step. Validation of the model by introduction of data of secreted adiponectin yielded a very close resemblance between the simulations and experimental results. Moreover, we could show that Ca2+-dependent adiponectin endocytosis contributes to the measured capacitance signal, and we were able to predict the contribution of endocytosis to the measured exocytotic rate under different experimental conditions. In conclusion, using mathematical modeling of published and newly generated data, we have obtained estimates of adiponectin exo- and endocytosis rates, and we have predicted adiponectin secretion. We believe that our model should have multiple applications in the study of metabolic processes and hormonal control thereof.
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Adipócitos Brancos/metabolismo , Adiponectina/metabolismo , Endocitose/fisiologia , Exocitose/fisiologia , Células 3T3-L1 , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico , Cálcio/metabolismo , Capacitância Elétrica , Cinética , Camundongos , Modelos Teóricos , Vesículas Transportadoras/metabolismoRESUMO
Shear-thinning, self-healing hydrogels are promising vehicles for therapeutic cargo delivery due to their ability to be injected using minimally invasive surgical procedures. We present an injectable hydrogel using a novel combination of dynamic covalent crosslinking with thermoresponsive engineered proteins. Ex situ at room temperature, rapid gelation occurs through dynamic covalent hydrazone bonds by simply mixing two components: hydrazine-modified elastin-like protein (ELP) and aldehyde-modified hyaluronic acid. This hydrogel provides significant mechanical protection to encapsulated human mesenchymal stem cells during syringe needle injection and rapidly recovers after injection to retain the cells homogeneously within a 3D environment. In situ, the ELP undergoes a thermal phase transition, as confirmed by Coherent anti-Stokes Raman scattering microscopy observation of dense ELP thermal aggregates. The formation of the secondary network reinforces the hydrogel and results in a 10-fold slower erosion rate compared to a control hydrogel without secondary thermal crosslinking. This improved structural integrity enables cell culture for three weeks post injection, and encapsulated cells maintain their ability to differentiate into multiple lineages, including chondrogenic, adipogenic, and osteogenic cell types. Together, these data demonstrate the promising potential of ELP-HA hydrogels for injectable stem cell transplantation and tissue regeneration.
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Hydrogels have been developed as extracellular matrix (ECM) mimics both for therapeutic applications and basic biological studies. In particular, elastin-like polypeptide (ELP) hydrogels, which can be tuned to mimic several biochemical and physical characteristics of native ECM, have been constructed to encapsulate various types of cells to create in vitro mimics of in vivo tissues. However, ELP hydrogels become opaque at body temperature because of ELP's lower critical solution temperature behavior. This opacity obstructs light-based observation of the morphology and behavior of encapsulated cells. In order to improve the transparency of ELP hydrogels for better imaging, we have designed a hybrid ELP-polyethylene glycol (PEG) hydrogel system that rapidly cross-links with tris(hydroxymethyl) phosphine (THP) in aqueous solution via Mannich-type condensation. As expected, addition of the hydrophilic PEG component significantly improves the light transmittance. Coherent anti-Stokes Raman scattering (CARS) microscopy reveals that the hybrid ELP-PEG hydrogels have smaller hydrophobic ELP aggregates at 37 °C. Importantly, this hydrogel platform enables independent tuning of adhesion ligand density and matrix stiffness, which is desirable for studies of cell-matrix interactions. Human fibroblasts encapsulated in these hydrogels show high viability (>98%) after 7 days of culture. High-resolution confocal microscopy of encapsulated fibroblasts reveals that the cells adopt a more spread morphology in response to higher RGD ligand concentrations and softer gel mechanics.
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Elastina , Matriz Extracelular , Fibroblastos/citologia , Hidrogéis , Peptídeos , Técnicas de Cultura de Células/métodos , Linhagem Celular , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Elastina/química , Elastina/farmacologia , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologiaRESUMO
We present a case report of a five-year-old male with acute ischemic stroke who underwent successful mechanical endovascular thrombectomy and early surgical resection of left atrial myxoma two days after onset of stroke symptoms without additional neurological sequelae.
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Neoplasias Cardíacas , AVC Isquêmico , Mixoma , Acidente Vascular Cerebral , Masculino , Humanos , Pré-Escolar , AVC Isquêmico/complicações , Átrios do Coração , Acidente Vascular Cerebral/etiologia , Neoplasias Cardíacas/cirurgia , Mixoma/cirurgiaRESUMO
BACKGROUND: Bacterial meningitis-induced ischemic stroke continues to cause significant long-term complications in pediatric patients. The authors present a case of severe right internal carotid artery terminus and M1 segment vasospasm in a 9-year-old with an infected cholesteatoma, which was refractory to multiple intraarterial treatments with verapamil and milrinone. This is the first report of continuous intraarterial antispasmodic treatment in a pediatric patient as well as the first report of continuous treatment in an awake and extubated patient. OBSERVATIONS: Arterial narrowing was successfully treated by continuous direct intraarterial administration of both a calcium channel blocker (verapamil) and a phosphodiesterase-3 inhibitor (milrinone). The patient recovered remarkably well and was discharged home with no neurological deficit (National Institutes of Health Stroke Scale score 0) and ambulatory without assistance after 22 days. The authors report a promising outcome of this technique performed in a pediatric patient. LESSONS: This represents a novel treatment option for the prevention of stroke in pediatric bacterial meningitis. Continuous, direct intraarterial administration of antispasmodic medications can successfully prevent long-term neurological deficit in pediatric meningitis-associated vasospasm. The described method has the potential to significantly improve outcomes in severe pediatric meningitis-associated vasospasm.
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BACKGROUND: Stroke presentation secondary to a cardiac myxoma thromboembolism is rare in the pediatric population. Because of such rarity, the reported cases in the literature are primarily case reports. Additionally, general pediatric stroke management lacks evidence-based guidelines because of its low incidence and lack of clinical trials. In pediatric strokes identified from a cardiac myxoma, the incidence favors boys with the classical presentation of unilateral weakness and aphasia. We present a pediatric patient who presented with strokelike symptoms secondary to an intracranial embolus from a previously undiagnosed cardiac myxoma. METHODS: We performed a systematic review by searching PubMed, Google Scholar, Web of Science, and Embase databases for cases of pediatric myxoma causing stroke (n = 2431) and identified 19 reported uses of surgical management in treating pediatric patients who present with stroke symptoms secondary to a cardiac myxoma thromboembolism. RESULTS: The most common imaging modality was magnetic resonance imaging in 42% of cases, computed tomography in 36.8%, followed by computed tomography angiography in 31.6% of cases. Of these 19 children treated with procedures, 36.8% of pediatric patients aged between 4 and 14 years underwent neurosurgery (n = 7). CONCLUSIONS: We describe an urgent mechanical thrombectomy and share preoperative and postoperative images and pathology slides confirming a stroke from myxoma origin. We provide added insight in the safe use of mechanical thrombectomy as treatment for pediatric strokes secondary to a thromboembolism.