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Endothelial cells (ECs) are critical to proper heart valve development, directly contributing to the mesenchyme of the cardiac cushions, which progressively transform into mature valves. To date, investigators have lacked sufficient markers of valve ECs to evaluate their contributions during valve morphogenesis fully. As a result, it has been unclear whether the well-characterized regional differentiation of valves correlates with any endothelial domains in the heart. Furthermore, it has been difficult to ascertain whether endothelial heterogeneity in the heart influences underlying mesenchymal zones in an angiocrine manner. To identify regionally expressed EC genes in the heart valves, we screened publicly available databases and assembled a toolkit of endothelial-enriched genes. We identified Cyp26b1 as one of many endothelial enriched genes found to be expressed in the endocardium of the developing cushions and valves. Here, we show that Cyp26b1 is required for normal heart valve development. Genetic ablation of Cyp26b1 in mouse embryos leads to abnormally thickened aortic valve leaflets, which is due in part to increased endothelial and mesenchymal cell proliferation in the remodeling valves. In addition, Cyp26b1 mutant hearts display ventricular septal defects (VSDs) in a portion of null embryos. We show that loss of Cyp26b1 results in upregulation of retinoic acid (RA) target genes, supporting the observation that Cyp26b1 has RA-dependent roles. Together, this work identifies a novel role for Cyp26b1 in heart valve morphogenesis and points to a role of RA in this process. Understanding the spatiotemporal expression dynamics of cardiac EC genes will pave the way for investigation of both normal and dysfunctional heart valve development.
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Células Endoteliais , Valvas Cardíacas , Animais , Valva Aórtica , Valvas Cardíacas/metabolismo , Camundongos , Morfogênese , Organogênese , Ácido Retinoico 4 Hidroxilase/genética , Ácido Retinoico 4 Hidroxilase/metabolismo , Tretinoína/metabolismoRESUMO
PURPOSE OF REVIEW: Benign prostatic hyperplasia (BPH) is a common disease in men. A rapidly rising demand for safe and effective therapy for BPH has generated novel minimally invasive surgical treatments (MISTs). With multiple procedural options in the urology armamentarium for BPH therapy, we describe the current therapies and outcomes for office-based procedures for BPH including quality of life, voiding symptoms, and sexual function. RECENT FINDINGS: There are three FDA-approved MISTs (Rezum, Urolift, and iTind) and three emerging MISTs for BPH. Preliminary data suggest improvement in voiding symptoms and quality of life while minimizing unwanted sexual side effects. Long term data is required on the durability and safety of MISTs for BPH. MISTs mark a paradigm shift in BPH management. Sandwiched between conservative medical management and conventional transurethral surgery, these novel technologies promise to combine efficacy approaching that of TURP while sparing the negative side effects. We envision a future where BPH can be diagnosed and treated in an office-based setting with a standard cystoscope in one procedure.
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Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Sintomas do Trato Urinário Inferior/cirurgia , Sintomas do Trato Urinário Inferior/terapia , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Hiperplasia Prostática/cirurgia , Qualidade de VidaRESUMO
INTRODUCTION: Radical inguinal orchiectomy (RO ) is indicated for the management of testicular tumors and is universally performed under general anesthetic in the hospital. The need to perform radical orchiectomy in an expeditated fashion can result in logistical difficulties, often necessitating this procedure to happen after-hours on a semi-emergent basis. These logistical difficulties have been exacerbated by the backlog of cases from the COVID-19 pandemic. A similar procedure - inguinal hernia repair - is regularly performed under local anesthesia with minimal complications. Thus, we sought to evaluate the feasibility of performing radical orchiectomy under deep intravenous sedation in an ambulatory surgery center. METHODS: We evaluated our single-surgeon (PP), prospective database of patients who underwent RO between September 2022 and February 2023 at the Men's Health Clinic Manitoba. Patients were given a combination of deep sedation, ilioinguinal nerve block, and local anesthetic. Tolerability was assessed both perioperatively and at 4-6 weeks' followup. We reviewed the medical records for any postoperative complications. RESULTS: Eight patients underwent RO under deep sedation during the study period. All patients tolerated the surgery well and were discharged shortly after surgery. Average operative time was 40 minutes and length of stay was 46 minutes. There were no perioperative complications. CONCLUSIONS: Our pilot study demonstrates that RO can be safely and effectively performed under deep sedation. This anesthetic combination can be used both in-hospital and out-of-hospital settings, thereby resulting in faster recovery, shorter length of stay, and favorable patient and provider satisfaction.
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Right-sided subclavian artery aneurysms (SAAs) are exceedingly rare. The most common cause of intrathoracic SAAs is atherosclerosis; however, causes can also include infection, trauma, cystic medial degeneration, Marfan syndrome, and Takayasu arteritis. Symptoms present most commonly with compression of surrounding structures, although adverse events, including rupture, thrombosis, and embolization, can also occur. We present a case of a 30-year-old woman with an asymptomatic, 15-mm, right-sided SAA, which was successfully resected with subsequent end-to-end primary anastomosis.
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Rheumatoid arthritis (RA), a chronic inflammatory condition that affects persons between the ages of 20 and 40, causes synovium inflammation, cartilage loss, and joint discomfort as some of its symptoms. Diagnostic techniques for RA have traditionally been split into two main categories: imaging and serological tests. However, significant issues are associated with both of these methods. Imaging methods are costly and only helpful in people with obvious symptoms, while serological assays are time-consuming and require specialist knowledge. The drawbacks of these traditional techniques have led to the development of novel diagnostic approaches. The unique properties of nanomaterials make them well-suited as biosensors. Their compact dimensions are frequently cited for their outstanding performance, and their positive impact on the signal-to-noise ratio accounts for their capacity to detect biomarkers at low detection limits, with excellent repeatability and a robust dynamic range. In this review, we discuss the use of nanomaterials in RA theranostics. Scientists have recently synthesized, characterized, and modified nanomaterials and biomarkers commonly used to enhance RA diagnosis and therapy capabilities. We hope to provide scientists with the promising potential that nanomaterials hold for future theranostics and offer suggestions on further improving nanomaterials as biosensors, particularly for detecting autoimmune disorders.
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CRISPR/Cas systems have revolutionized biology and medicine, and have led to new paradigms in disease diagnostics and therapeutics. However, these complexes suffer from key limitations regarding barriers to cellular entry, stability in biological environments, and off-target effects. Integrating nanotechnology with CRISPR/Cas systems has emerged as a promising strategy to overcome these challenges and has further unlocked structures that accumulate preferentially in tissues of interest, have tunable pharmacological properties, and are activated in response to desired stimuli. Nanomaterials can also enhance CRISPR/Cas-mediated detection platforms by enabling faster, more sensitive, and convenient readouts. We highlight recent advances in this rapidly growing field. We also outline areas that need further development to fully realize the potential of CRISPR technologies.
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Sistemas CRISPR-Cas , Edição de Genes , NanotecnologiaRESUMO
BPH is a common disease in aging men which impacts quality of life. With advancing age expectation coupled with the rising demand for BPH therapy, new technologies have been developed that target rapid recovery and symptom relief, low complication rates, and the ability to perform the procedure in an outpatient setting with local anesthesia. MIST technologies have fostered BPH medical care with ejaculation preservation. Techniques and outcomes for BPH technologies including Aquablation, Rezum, UroLift, iTind, Optilume BPH, XFLO, Zenflow, and Butterfly are reviewed and evaluated. Given the novelty of these technologies, long-term data are required to assess safety and efficacy.
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Técnicas de Ablação , Hiperplasia Prostática/cirurgia , Próteses e Implantes , Cateteres Urinários , Técnicas de Ablação/efeitos adversos , Ligas , Antineoplásicos Fitogênicos/uso terapêutico , Dilatação/instrumentação , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Paclitaxel/uso terapêutico , Próteses e Implantes/efeitos adversos , Procedimentos Cirúrgicos Robóticos , Vapor , Cateteres Urinários/efeitos adversosRESUMO
In the ongoing search for the optimal biomaterial for tissue engineered vascular grafts (TEVGs), poly (glycerol sebacate) (PGS) has emerged as a new potential candidate. We have utilized a novel method to create unique, pore-free, extruded PGS grafts with and without a supportive exterior layer of polyglycolic acid (PGA). The 1 mm diameter by 5 mm length TEVGs were implanted in a rat model of infrarenal abdominal aorta interposition grafting. Three months after implantation, TEVGs comprised of extruded PGS with an external PGA braid demonstrated a patency rate of 9/10 (90%) with no signs of dilatation, dehiscence, or rupture. The PGS/PGA graft was remodeled into a neoartery with complete endothelialization of the neoartery lumen and formation of smooth muscle actinin multilayers as demonstrated via immunohistochemistry. Formation and maturation of extracellular matrix material were also observed, with amounts of elastin and collagen comparable to native rat aorta. No significant host inflammatory response was observed. These findings suggest the combination of an extruded PGS tube with an external reinforcing PGA braid is a promising material for small diameter TEVGs.
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Glicerol , Ácido Poliglicólico , Animais , Materiais Biocompatíveis , Prótese Vascular , Matriz Extracelular , Glicerol/farmacologia , Ratos , Engenharia Tecidual , Alicerces TeciduaisRESUMO
A 78-year-old woman with a remote history of chronic atrial fibrillation and catheter ablation of the atrioventricular node with a permanent ventricular pacemaker sustained a syncopal episode. Interrogation of her pacemaker revealed electrograms of ventricular fibrillation with a duration of 26 seconds. The patient underwent upgrade to an implantable cardioverter defibrillator (ICD). Postimplant, on telemetry, pauses were seen without pacing artifact, suspicious for oversensing of something by the ICD. Interrogation and threshold testing of the ICD established that both sensing (of her junctional escape rhythm) and pacing thresholds were excellent. A Holter monitor was utilized to evaluate the patient's rhythm and device function. It incorporated simultaneous tracings from multiple surface electrocardiogram leads and both intracardiac electrograms and marker channel recordings from the ICD. The causes for the pauses were found to be isoelectric premature ventricular complexes not seen on the telemetry tracings.
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Desfibriladores Implantáveis , Eletrocardiografia Ambulatorial/métodos , Taquicardia Ventricular/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , HumanosRESUMO
BACKGROUND: In hepato-pancreato-biliary (HPB) surgery higher volumes are associated with improved outcomes; however, there are limitations to regionalization. Here we report our experience establishing multidisciplinary HPB program at a university-affiliated community hospital. METHODS: This is a retrospective review of patients who underwent HPB surgery between 2015 and 2017. Chief residents' HPB case logs were collected. RESULTS: 61 pancreatic resections and 62 hepatic resections were performed. The morbidity, 30-day mortality and median length of stay following pancreatic resections were 27%, 1.5%, and 8 days, respectively. The morbidity, 90-day mortality, and median length of stay following hepatic resections were 24%, 3%, and 7 days, respectively. The median pancreatic and liver case volumes for graduating chief residents increased from 7 to 8 to 16 and 16, respectively (pâ¯<â¯0.05), after the establishment of a HPB program. Participation in multidisciplinary care (pâ¯=â¯0.08) and clinical trial enrollment increased. CONCLUSION: Our study demonstrates short-term outcomes comparable to high volume centers. Development of a HPB program had a positive impact on resident operative experience, increased multidisciplinary care and increased clinical trial enrollment.
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Hepatectomia/estatística & dados numéricos , Hospitais Comunitários/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Hepatopatias/cirurgia , Pancreatectomia/estatística & dados numéricos , Pancreatopatias/cirurgia , Idoso , Ensaios Clínicos como Assunto , Estudos de Viabilidade , Feminino , Hepatectomia/efeitos adversos , Humanos , Internato e Residência/estatística & dados numéricos , Hepatopatias/epidemiologia , Masculino , Michigan/epidemiologia , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Pancreatectomia/efeitos adversos , Pancreatopatias/epidemiologia , Equipe de Assistência ao Paciente , Estudos RetrospectivosRESUMO
INTRODUCTION: Ranking candidates for residency positions is challenging. We hypothesize that applicant academic achievements and performance during the interview are equally important in the ranking process. METHODS: This is a retrospective study. Of 53 candidates interviewed during 2016-2017 cycle, 44 (83%) were ranked for 3 PGY1 positions. Each candidate was interviewed and scored in each of the following: USMLE Step 1 score, USMLE Step 2 score, research (RS), letters of recommendation (LOR), personal statement (PS), the way the candidate represented him/herself (RP), interest in the area (IN), answers to standardized questions (SQ), and degree of connection between the candidate and the interviewer (CN). RESULTS: Correlation and multiple regression analyses indicated an inverse relationship between ranking the candidates and USMLE2 (râ¯=â¯-0.14, pâ¯=â¯-0.364), LOR (râ¯=â¯-0.513, pâ¯<â¯0.001), PS (râ¯=â¯-0.414, pâ¯=â¯0.006), RP (râ¯=â¯-0.485, pâ¯=â¯0.001), CN (râ¯=â¯-0.605, pâ¯<â¯0.001), IN (râ¯=â¯-0.349, pâ¯=â¯0.022), and SQ (râ¯=â¯-0.480, pâ¯=â¯0.001), USMLE1 (râ¯=â¯-0.036, pâ¯=â¯0.838) and RS (râ¯=â¯-0.008, pâ¯=â¯0.96). After controlling for the other variables, only CN reached statistical significance (pâ¯=â¯0.033). CONCLUSION: Candidate non-cognitive measures during the interview weigh higher than academic performance in the ranking process.
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Sucesso Acadêmico , Cirurgia Geral/educação , Seleção de Pessoal , Psicometria , Adulto , Avaliação Educacional , Feminino , Humanos , Internato e Residência , Masculino , Estudos Retrospectivos , Critérios de Admissão Escolar , Estados UnidosRESUMO
IMPACT STATEMENT: We utilized innovative textile technology to create tissue-engineered vascular grafts (TEVGs) comprised exclusively of rapidly degrading material poly(glycolic acid). Our new technology led to robust neotissue formation in the TEVGs, especially extracellular matrix formation, such as elastin. In addition, the rapid degradation of the polymer significantly reduced complications, such as stenosis or calcification, as seen with the use of slow degrading polymers in the majority of previous studies for aortic small diameter TEVGs.
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Engenharia Tecidual/métodos , Animais , Implante de Prótese Vascular/métodos , Constrição Patológica/cirurgia , Polímeros/químicaRESUMO
BACKGROUND: Thromboelastography has called into question the coagulopathy seen following partial hepatectomy. However the coagulation profile in cirrhotic livers has not been studied. Our objective was to determine the coagulation profile following partial hepatectomy in normal and cirrhotic livers. METHODS: Patients undergoing liver resection were prospectively enrolled in the study. The prothrombin time and international normalized ratio, as well as the thromboelastogram, were obtained preoperatively, post-operatively, and on post-operative days 1, 3, and 5. RESULTS: 22 noncirrhotic and 11 cirrhotic patients undergoing liver resection were enrolled. Postoperatively the thromboelastogram demonstrated a hypercoagulable profile in 64%, 33%, 39% and 36% of patients on post-operative days 0, 1, 3 and 5 respectively. There was no difference between patients with cirrhosis and those without underlying liver disease. CONCLUSION: Patients appear to have a similar coagulation profile after liver resection regardless of underlying cirrhosis with many having a hypercoagulable profile.
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Hepatectomia , Cirrose Hepática/complicações , Complicações Pós-Operatórias/etiologia , Tromboelastografia , Trombofilia/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Tempo de Protrombina , Fatores de Risco , Trombofilia/diagnóstico , Trombofilia/epidemiologiaRESUMO
BACKGROUND CONTEXT: Recombinant growth factors bone morphogenetic protein-2 (BMP-2) and BMP-7 are currently approved for human use but are associated with various adverse effects including ectopic bone formation and local inflammatory reaction. The development of alternative growth factors may help minimize the adverse effects of current osteoinductive therapeutics. Nell-1 (Nel-like molecule-1; Nel [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel secretory molecule that appears to act more specifically on osteoblasts than the BMPs, which can act on multiple cell types. From a molecular point of view, Nell-1 is directly regulated by runt-related transcription factor 2 (Runx2/Cbfa1), a master regulatory gene controlling bone formation. Previous studies showed that Nell-1 accelerates osteogenic differentiation in vitro and calvarial bone formation in vivo. We hypothesize that Nell-1 may also effectively form bone in spinal fusion. PURPOSE: Our primary aim was to assess if direct adenoviral gene delivery with Nell-1 in a demineralized bone matrix (DBM) carrier can improve spinal fusion in a rat model. Because adenoviral vectors allow for sustained growth factor delivery, they were used for initial feasibility testing before protein studies. STUDY DESIGN/SETTING: Two groups of 20 athymic rats underwent posterolateral intertransverse process spinal fusion at L4-L5 with implanted DBM carrier containing either adenovirus coding for Nell-1 (AdNell-1) or control, Lac Z (AdLacZ). No cells were implanted. The 20 rats were sacrificed at 6 weeks for evaluation of spinal fusion. METHODS: All animals underwent Faxitron radiographs at 2, 4, and 6 weeks, manual spine palpation at 6 weeks, and high-resolution micro computerized tomography (microCT) at 6 weeks. Spinal fusion rate was assessed by: 1) 6-week Faxitron images; 2) manual palpation by three independent observers; 3) microCT; and 4) histology. New bone formation was assessed by hematoxylin-eosin and Masson trichrome staining on decalcified, coronally sectioned spine segments. RESULTS: All differences achieved statistical significance. After 6 weeks, direct application of adenoviral Nell-1 in a DBM carrier achieved significantly higher rates of spinal fusion over Lac Z controls: 60% Nell-1 versus 20% Lac Z by manual palpation and 70% Nell-1 versus 20% Lac Z by microCT and histology. Histological assessment of bone quality and maturity revealed more mature, higher quality bone in all the Nell-1 treated specimens relative to Lac Z at 6 weeks. CONCLUSIONS: Spinal fusion is more accurately assessed by microCT and histology than manual palpation. Direct application of adenoviral Nell-1 in a DBM carrier achieved significantly higher rates of spinal fusion over Lac Z controls at 6 weeks. Direct application of adenoviral Nell-1 in a DBM carrier also achieved significantly higher rates of spinal fusion over other reports in the literature using direct adenoviral BMP application. Direct application of adenoviral BMP in an allograft carrier achieved 8% fusion for BMP-2 and 16% fusion for BMP-7 at 8 weeks. These results indicate that Nell-1 may be a potent osteoinductive molecule. In addition, the regulation of Nell-1 by the master bone regulatory gene, Runx2 suggests that Nell-1 may exert its effects more specifically in osteoblastic cells than BMPs which affect multiple cell types. Overall, Nell-1 may fulfil a current need for an osteoinductive factor.
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Terapia Genética/métodos , Proteínas do Tecido Nervoso/genética , Osseointegração/genética , Osteogênese/genética , Fusão Vertebral/métodos , Adenoviridae/genética , Animais , Matriz Óssea/transplante , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Nus , Ratos Sprague-Dawley , Fusão Vertebral/instrumentação , Tomografia Computadorizada por Raios X , Transdução Genética/métodosRESUMO
Due to the lack of cell-adhesive moieties in traditional synthetic hydrogels, the present work investigated the use of degradable gelatin microparticles (GMPs) as temporary adherent substrates for anchorage-dependent mesenchymal stem cells (MSCs). MSCs were seeded onto GMPs of varying crosslinking densities and sizes to investigate their role on influencing MSC differentiation and aggregation. The MSC-seeded GMPs were then encapsulated in poly(ethylene glycol)-based hydrogels and cultured in serum-free, growth factor-free osteochondral medium. Non-seeded MSCs co-encapsulated with GMPs in the hydrogels were used as a control for comparison. Over the course of 35 days, MSCs seeded on GMPs exhibited more cell-cell contacts, greater chondrogenic potential, and a down-regulation of osteogenic markers compared to the controls. Although the factors of GMP crosslinking and size had nominal influence on MSC differentiation and aggregation, GMPs demonstrate potential as an adherent-substrate for improving cell delivery from hydrogel scaffolds by facilitating cell-cell contacts and improving MSC differentiation.
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Antígenos de Diferenciação/biossíntese , Diferenciação Celular , Condrogênese , Gelatina/química , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Animais , Células Cultivadas , Células-Tronco Mesenquimais/citologia , Polietilenoglicóis/química , CoelhosRESUMO
The Kemp elimination is prototypical reaction used to study proton abstraction from carbon. Several hydrophobic systems are known to accelerate this reaction, including two classes of computationally-designed enzymes. However, it is unclear whether these computationally-designed enzymes establish specific interactions with their substrates, as natural enzymes do, or if most of the rate acceleration is due to the hydrophobicity of the substrate. We used a simple system composed of cationic micelles and a long chain base (such as lauryl phosphate or lauric acid) to measure the rate acceleration for the Kemp elimination. Remarkably, we found that this simple system can accelerate the reaction by 4 orders of magnitude, approaching the rates of more complex designed systems. Use of different substrates suggests that the reaction takes place at the interface between the micellar head and water (the Stern layer) with the long-chain base embedded in the micelle and the substrate in the aqueous solution. Thus, we suggest that significant rate accelerations can be achieved regardless of the precise positioning of substrates. Because natural enzymes use specific interactions to position their substrates, we propose that acceleration of the Kemp elimination is not a suitable benchmark for the success of the design process, and we suggest that more complex reactions should be used.
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To address the lack of reliable long-term solutions for cartilage injuries, strategies in tissue engineering are beginning to leverage developmental processes to spur tissue regeneration. This study focuses on the use of poly(L-lysine) (PLL), previously shown to up-regulate mesenchymal condensation during developmental skeletogenesis in vitro, as an early chondrogenic stimulant of mesenchymal stem cells (MSCs). We characterized the effect of PLL incorporation on the swelling and degradation of oligo(poly(ethylene) glycol) fumarate) (OPF)-based hydrogels as functions of PLL molecular weight and dosage. Furthermore, we investigated the effect of PLL incorporation on the chondrogenic gene expression of hydrogel-encapsulated MSCs. The incorporation of PLL resulted in early enhancements of type II collagen and aggrecan gene expression and type II/type I collagen expression ratios when compared to blank controls. The presentation of PLL to MSCs encapsulated in OPF hydrogels also enhanced N-cadherin gene expression under certain culture conditions, suggesting that PLL may induce the expression of condensation markers in synthetic hydrogel systems. In summary, PLL can function as an inductive factor that primes the cellular microenvironment for early chondrogenic gene expression but may require additional biochemical factors for the generation of fully functional chondrocytes.
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Cartilagem/fisiologia , Eletrólitos/farmacologia , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Polilisina/farmacologia , Engenharia Tecidual/métodos , Animais , Cartilagem/efeitos dos fármacos , Galinhas , Condrogênese/efeitos dos fármacos , Condrogênese/genética , DNA/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Fumaratos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glicosaminoglicanos/metabolismo , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Peso Molecular , Tamanho da Partícula , Polietilenoglicóis/farmacologia , Coelhos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genéticaRESUMO
The underlying mechanisms of alpha band (8-12 Hz) neural oscillations are of importance to the functioning of attention control systems as well as to neuropsychiatric conditions that are characterized by deficits of that system, such as attention deficit hyperactivity disorder (ADHD). The objectives of the present study were to test if visual encoding-related alpha event-related desynchronization (ERD) correlates with fronto-parieto-occipital connectivity, and whether this is disrupted in ADHD during spatial working memory (SWM) performance. We acquired EEG concurrently with fMRI in thirty boys (12-16 yrs. old, 15 with ADHD), during SWM encoding. Psychophysiological connectivity analyses indicated that alpha ERD during SWM encoding was associated with both occipital activation and fronto-parieto-occipital functional connectivity, a finding that expands on prior associations between alpha ERD and occipital activation. This finding provides novel support for the interpretation of alpha ERD (and the associated changes in occipital activation) as a phenomenon that involves, and perhaps arises as a result of, top-down network interactions. Alpha ERD was associated less strongly with occipital activity, but associated more strongly with fronto-parieto-occipital connectivity in ADHD, consistent with a compensatory attentional response. Additionally, we illustrate that degradation of EEG data quality by MRI-amplified motion artifacts is robust to existing cleaning algorithms and is significantly correlated with hyperactivity symptoms and the ADHD Combined Type diagnosis. We conclude that persistent motion-related MR artifacts in EEG data can increase variance and introduce bias in interpretation of group differences in populations characterized by hypermobility--a clear limitation of current-state EEG-fMRI methodology.
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Ritmo alfa/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade , Córtex Cerebral/diagnóstico por imagem , Eletroencefalografia , Imageamento por Ressonância Magnética , Memória de Curto Prazo/fisiologia , Adolescente , Análise de Variância , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Rede Nervosa/diagnóstico por imagem , Oxigênio/sangue , Escalas de Graduação Psiquiátrica , Aprendizagem Espacial/fisiologiaRESUMO
This data article presents data associated with the research article entitled "Evaluation of cell-laden polyelectrolyte hydrogels incorporating poly(L-lysine) for applications in cartilage tissue engineering" (Lam et al., 2016) [1]. Synthetic hydrogel composites fabricated using oligo(poly(ethylene glycol) fumarate) (OPF) macromers were utilized as vehicles for the incorporation of poly(L-lysine) (PLL) as well as the encapsulation of mesenchymal stem cells (MSCs). PLL-laden and PLL-free hydrogels were fabricated to characterize the main and interaction effects of OPF molecular weight, PLL molecular weight, and PLL loading density on the swelling and degradation of synthetic OPF hydrogels. Cells were then encapsulated within such hydrogels for in vitro culture and examined for viability, biochemical activity, and chondrogenic gene expression. These data, which are supplementary to the associated research article (Lam et al., 2016) [1], are presented here.