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We report a resonant cavity infrared detector (RCID) with an InAsSb/InAs superlattice absorber with a thickness of only ≈ 100â nm, a 33-period GaAs/Al0.92Ga0.08As distributed Bragg reflector bottom mirror, and a Ge/SiO2/Ge top mirror. At a low bias voltage of 150â mV, the external quantum efficiency (EQE) reaches 58% at the resonance wavelength λres ≈ 4.6â µm, with linewidth δλ = 19-27â nm. The thermal background current for a realistic system scenario with f/4 optic that views a 300â K scene is estimated by integrating the photocurrent generated by background spanning the entire mid-IR spectral band (3-5â µm). The resulting specific detectivity is a factor of 3 lower than for a state-of-the-art broadband HgCdTe device at 300â K, where dark current dominates the noise. However, at 125â K where the suppression of background noise becomes critical, the estimated specific detectivity D* of 5.5 × 1012â cm Hz½/W is more than 3× higher. This occurs despite a non-optimal absorber cut-off that causes the EQE to decrease rapidly with decreasing temperature, e.g., to 33% at 125â K. The present RCID's advantage over the broadband device depends critically on its low EQE at non-resonance wavelengths: ≤ 1% in the range 3.9-5.5â µm. Simulations using NRL MULTIBANDS indicate that impact ionization in the bottom contact and absorber layers dominates the dark current at near ambient temperatures. We expect future design modifications to substantially enhance D* throughout the investigated temperature range of 100-300â K.
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OBJECTIVE: Persistent hydrocephalus following posterior fossa brain tumor (PFBT) resection is a common cause of morbidity in pediatric brain tumor patients, for which the optimal treatment is debated. The purpose of this study was to compare treatment outcomes between VPS and ETV in patients with persistent hydrocephalus following surgical resection of a PFBT. METHODS: A post-hoc analysis was performed of the Hydrocephalus Clinical Research Network (HCRN) prospective observational study evaluating VPS and ETV for pediatric patients. Children who experienced hydrocephalus secondary to PFBT from 2008 to 2021 were included. Primary outcomes were VPS/ETV treatment failure and time-to-failure (TTF). RESULTS: Among 241 patients, the VPS (183) and ETV (58) groups were similar in age, extent of tumor resection, and preoperative ETV Success Score. There was no difference in overall treatment failure between VPS and ETV (33.9% vs 31.0%, p = 0.751). However, mean TTF was shorter for ETV than VPS (0.45 years vs 1.30 years, p = 0.001). While major complication profiles were similar, compared to VPS, ETV patients had relatively higher incidence of minor CSF leak (10.3% vs. 1.1%, p = 0.003) and pseudomeningocele (12.1% vs 3.3%, p = 0.02). No ETV failures were identified beyond 3 years, while shunt failures occurred beyond 5 years. Shunt infections occurred in 5.5% of the VPS cohort. CONCLUSIONS: ETV and VPS offer similar overall success rates for PFBT-related postoperative hydrocephalus. ETV failure occurs earlier, while susceptibility to VPS failure persists beyond 5 years. Tumor histology and grade may be considered when selecting the optimal means of CSF diversion.
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Hidrocefalia , Neoplasias Infratentoriais , Neuroendoscopia , Criança , Humanos , Ventriculostomia/efeitos adversos , Neuroendoscopia/efeitos adversos , Derivação Ventriculoperitoneal/efeitos adversos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Hidrocefalia/epidemiologia , Resultado do Tratamento , Neoplasias Infratentoriais/complicações , Neoplasias Infratentoriais/cirurgia , Estudos RetrospectivosRESUMO
PURPOSE OF REVIEW: The tissue damage and trauma associated with surgery almost always result in acute postoperative pain. The intensity of postoperative pain can range from mild to severe. Naltrexone is suitable for patients who do not wish to be on an agonist treatment such as methadone or buprenorphine. However, naltrexone has been shown to complicate postoperative pain management. RECENT FINDINGS: Multiple studies have found that the use of naltrexone can increase the opioid requirement for postoperative pain control. Other modalities exist that can help outside of opioids such as ketamine, lidocaine/bupivacaine, duloxetine, and non-pharmacological management can help manage pain. Multimodal pain regiments should also be employed in patients. In addition to traditional methods for postoperative pain management, other methods of acute pain control exist that can help mitigate opioid dependence and help control pain in patients who use naltrexone for their substance use disorders.
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Dor Aguda , Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Humanos , Naltrexona/uso terapêutico , Dor Aguda/tratamento farmacológico , Tratamento de Substituição de Opiáceos/métodos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Buprenorfina/uso terapêutico , Metadona/uso terapêutico , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológicoRESUMO
PURPOSE OF REVIEW: Regardless of the etiology, if pain persists chronically, it can detrimentally impact multiple aspects of a patient's well-being. Both physical and psychological effects are significant in many chronic pain patients. In this regard, psychological consequences can alter a patient's quality of life, functionality, and social functioning. Opioids have been the long-established gold standard for acute pain treatment in settings such as the postoperative period. An alternative to opioids in pain management has been highly sought after. Through a non-selective mechanism, cebranopadol is a first-in-class oral drug which combines agonism of the mu and nociceptin opioid peptide (NOP) receptors to provide improved analgesia, while reducing the occurrence of many typically opioid side effects. This manuscript is a narrative review of the possible use of cebranopadol in pain management. RECENT FINDINGS: In pre-clinical studies, cebranopadol was similar to morphine in its pain control efficacy. In a phase IIa trial, cebranopadol was superior to placebo in reducing pain. In a randomized clinical trial, cebranopadol was superior to morphine. Another study concluded that cebranopadol had a lower misuse potential when compared to hydromorphone. In summary, cebranopadol offers new opportunities in treating chronic moderate to severe pain, while also countering risks of addiction. Additional studies are warranted to further evaluate the safety and efficacy of cebranopadol. In this regard, cebranopadol could prove to be a promising alternative to current pain treatment options.
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Dor Crônica , Humanos , Dor Crônica/tratamento farmacológico , Qualidade de Vida , Morfina/uso terapêutico , Indóis/efeitos adversos , Analgésicos Opioides/uso terapêutico , Receptor de Nociceptina , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase II como AssuntoRESUMO
PURPOSE OF REVIEW: Postoperative pain (POP) is among the most unpleasant experiences that patients face after surgery. Interest in and use of N-methyl-D-aspartate (NMDA) receptor antagonists for the management of POP has increased over the years with ketamine being the most popular drug of this class. RECENT FINDINGS: Several randomized controlled trials found that the use of ketamine either alone or in combination with other medications leads to decreased postoperative pain and opioid consumption. However, there are other studies that have not found these benefits. The results as of now suggest that the role of intraoperative ketamine in postoperative pain control varies among different operative procedures. While some studies have shown promise in ketamine's potential use as a postoperative analgesic, there is still a great deal of proposed research and randomized controlled trials needed to deduce the most efficacious and tolerable form and dose of ketamine.
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Ketamina , Humanos , Ketamina/uso terapêutico , Analgésicos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológicoRESUMO
PURPOSE OF REVIEW: Opioid use disorder (OUD) is a chronic disorder in which a person loses control over the use of opioids, develops a compulsive behavior, and defends the use despite knowing the negative consequences. There are numerous treatments for OUD, including buprenorphine. Since it is displacing a full agonist opioid, precipitated withdrawal can occur with standard inductions involving buprenorphine. RECENT FINDINGS: Case reports have noted success with a low-dose initiation of buprenorphine, which is different from typical protocols, relatively limited by adverse effects when patients were recently administered full agonists. A cohort investigation studied the use of a transdermal patch as part of the protocol, which was fairly well tolerated. While ongoing research is being conducted on this topic, recent case studies and smaller cohort studies have demonstrated the feasibility of a trial to treat OUD with low-dose initiation of buprenorphine.
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Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Humanos , Buprenorfina/uso terapêutico , Analgésicos Opioides/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Tratamento de Substituição de Opiáceos/métodos , Doença CrônicaRESUMO
Nearly 27 million people have an opioid use disorder (OUD) according to the 2016 Global Burden of Disease study, most of which occur in the US where opioids are a common class of medication used to treat acute and chronic pain. In 2016 alone, more than 60 million patients had at least one prescription for opioids filled or refilled. Over the past decade, prescription rates have risen astronomically and have created an epidemic in the US dubbed the "opioid crisis." In this regard, there has been an increase in overdoses and OUD diagnoses. Several studies have found dysregulation of balance between several neurotransmitters involved in the neural circuitry that subserves several behavioral domains, such as reward recognition, motivation, learning, and memory, affect, stress, and executive function, that contribute to the manifestation of craving. On the horizon is a new treatment approach consisting of the neuropeptide oxytocin, which may be involved in the overlapping mechanisms of stable attachment formation and coping with stress. Through this mechanism, it can shift processing from novelty and reward-seeking to an appreciation of familiarity and thus reduce stress and increase resilience in the face of addiction. It has been hypothesized that there is a connection between the glutaminergic and oxytocinergic systems, making oxytocin a possible therapeutic agent in reducing drug-induced actions seen in OUD patients. This manuscript will review the potential and feasible use of oxytocin in treating OUD.
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Dor Crônica , Overdose de Drogas , Transtornos Relacionados ao Uso de Opioides , Humanos , Analgésicos Opioides/uso terapêutico , Ocitocina/uso terapêutico , Ocitocina/fisiologia , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Overdose de Drogas/tratamento farmacológico , Dor Crônica/tratamento farmacológicoRESUMO
PURPOSE: To compare the outcomes of conducting left and right hemisphere surgical revascularization on the same day versus different days for bilateral pediatric moyamoya arteriopathy patients. METHODS: We retrospectively analyzed mortality, stroke, and transient neurologic event (TNE) rates in North American bilateral pediatric moyamoya arteriopathy patients who underwent bilateral cerebral revascularization. RESULTS: A total of 38 pediatric (≤ 18 years old) patients at our institution underwent bilateral cerebral revascularization for moyamoya arteriopathy. Of these patients, 24 (63.2%) had both operations on the same day and 14 (36.8%) had the two operations on different days. The average length of stay for patients who underwent same-day bilateral revascularization was 6.9 ± 2.0 days and the average length of stay for each operation for patients who underwent staged bilateral revascularization was 4.5 ± 1.4 days, p = 0.001. While there were 7 (14.6%) postoperative strokes in patients who had both hemispheres revascularized on the same day, 0 (0%) strokes occurred in hemispheres after they had been operated on in the staged cohort, p = 0.042. Additionally, the postoperative stroke-free survival time in the ipsilateral hemisphere and TNE-free survival time were significantly longer in patients in the staged revascularization cohort. CONCLUSION: Same-day bilateral revascularization was associated with longer length of stay per operation, higher rate of ipsilateral stroke, and shorter postoperative TNE-free and stroke-free survival time in the revascularized hemisphere.
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Revascularização Cerebral , Doença de Moyamoya , Acidente Vascular Cerebral , Humanos , Criança , Adolescente , Estudos Retrospectivos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Procedimentos Cirúrgicos Vasculares , Resultado do TratamentoRESUMO
Saethre-Chotzen syndrome (SCS) is a known craniosynostosis syndrome with a variable presentation of craniofacial and somatic involvement. Congenital coronal craniosynostosis is most commonly observed in SCS; however, progressive postnatal craniosynostosis of other sutures has been reported. The authors present 2 infants with progressive postnatal craniosynostosis and SCS caused by chromosome 7p deletions including the TWIST1 gene. The evolution of their clinical features and a literature review of patients with syndromic, postnatal progressive craniosynostosis illustrate the importance of longitudinal observation and management of these patients.
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Acrocefalossindactilia , Craniossinostoses , Lactente , Humanos , Deleção de Genes , Proteína 1 Relacionada a Twist/genética , Acrocefalossindactilia/genética , Craniossinostoses/genética , Deleção Cromossômica , Proteínas Nucleares/genéticaRESUMO
BACKGROUND: Delirium is an important risk factor for subsequent dementia. However, the field lacks large studies with long-term follow-up of delirium in subjects initially free of dementia to clearly establish clinical trajectories. METHODS: We undertook a retrospective cohort study of all patients over the age of 65 diagnosed with an episode of delirium who were initially dementia free at onset of delirium within National Health Service Greater Glasgow & Clyde between 1996 and 2020 using the Safe Haven database. We estimated the cumulative incidence of dementia accounting for the competing risk of death without a dementia diagnosis. We modelled the effects of age at delirium diagnosis, sex and socioeconomic deprivation on the cause-specific hazard of dementia via cox regression. RESULTS: 12 949 patients with an incident episode of delirium were included and followed up for an average of 741 days. The estimated cumulative incidence of dementia was 31% by 5 years. The estimated cumulative incidence of the competing risk of death without dementia was 49.2% by 5 years. The cause-specific hazard of dementia was increased with higher levels of deprivation and also with advancing age from 65, plateauing and decreasing from age 90. There did not appear to be a relationship with sex. CONCLUSIONS: Our study reinforces the link between delirium and future dementia in a large cohort of patients. It highlights the importance of early recognition of delirium and prevention where possible.
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OBJECTIVE: Screening for cervical spine injury after blunt trauma is common, but there remains varied practice patterns and clinical uncertainty regarding adequate radiographic evaluation. An oft-cited downside of MRI is the added risk compared to CT in the pediatric population; however, these specific risks have not yet been reported. This study examines the risks of cervical spine MRI in pediatric trauma patients in the context of what value MRI adds. METHODS: This was a retrospective observational study of all pediatric blunt trauma patients who were evaluated with a cervical spine MRI over a 4-year period at a level 1 pediatric trauma center. Clinical and radiographic data were abstracted, as well as anesthesia requirements and MRI-related major adverse events. CT and MRI results were compared for their ability to detect clinically unstable injuries - those requiring halo or surgery. RESULTS: There was one major adverse event related to MRI among the 269 patients who underwent cervical spine MRI - a rate of 0.37%. While 55% of children had an airway and anesthesia for MRI, only 57% of these airways were newly placed for the MRI. None of the 85 patients newly intubated for MRI developed aspiration pneumonitis or ventilator-associated pneumonia, and no patients had a significant neurologic event while at MRI. Another area of the body was imaged concurrently with the cervical spine MRI in 64% of patients and 83% of MRIs were performed within 48 h. CT and MRI were both 100% sensitive for injuries requiring halo or operative intervention. Eighty-three patients had an MRI performed after a negative CT, 11% (9/83) of these patients had a clinically stable injury detected on subsequent MRI, and none of these patients presented for delayed cervical spine complications. CONCLUSIONS: Overall, the safety profile of MRI in this setting is excellent and less than one-third of patients need new airway and anesthesia solely for MRI. In this clinical scenario, MRIs can happen relatively quickly and many patients require another body part to be imaged concurrently anyway. MRI and CT were both 100% sensitive for clinically unstable injuries. In the appropriate patients, MRI remains a safe and radiation-free alternative to CT.
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Lesões do Pescoço , Traumatismos da Coluna Vertebral , Ferimentos não Penetrantes , Humanos , Criança , Tomada de Decisão Clínica , Tomografia Computadorizada por Raios X/métodos , Incerteza , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Lesões do Pescoço/complicações , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/lesões , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/complicações , Estudos RetrospectivosRESUMO
BACKGROUND: Recent advances in three-dimensional (3D) printing and augmented reality (AR) have expanded anatomical modeling possibilities for caregiver craniosynostosis education. The purpose of this study is to characterize caregiver preferences regarding these visual models and determine the impact of these models on caregiver understanding of craniosynostosis. METHODS: The authors constructed 3D-printed and AR craniosynostosis models, which were randomly presented in a cross-sectional survey. Caregivers rated each model's utility in learning about craniosynostosis, learning about skull anatomy, viewing an abnormal head shape, easing anxiety, and increasing trust in the surgeon in comparison to a two-dimensional (2D) diagram. Furthermore, caregivers were asked to identify the fused suture on each model and indicate their preference for generic versus patient-specific models. RESULTS: A total of 412 craniosynostosis caregivers completed the survey (mean age 33âyears, 56% Caucasian, 51% male). Caregivers preferred interactive, patient-specific 3D-printed or AR models over 2D diagrams (mean score difference 3D-printed to 2D: 0.16, Pâ<â0.05; mean score difference AR to 2D: 0.17, Pâ<â0.01) for learning about craniosynostosis, with no significant difference in preference between 3D-printed and AR models. Caregiver detection accuracy of the fused suture on the sagittal model was 19% higher with the 3D-printed model than with the AR model (Pâ<â0.05) and 17% higher with the 3D-printed model than with the 2D diagram (Pâ<â0.05). CONCLUSIONS: Our findings indicate that craniosynostosis caregivers prefer 3D-printed or AR models over 2D diagrams in learning about craniosynostosis. Future craniosynostosis skull models with increased user interactivity and patient-specific components can better suit caregiver preferences.
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Realidade Aumentada , Craniossinostoses , Adulto , Cuidadores , Estudos Transversais , Feminino , Humanos , Imageamento Tridimensional , Masculino , Modelos Anatômicos , Impressão Tridimensional , CrânioRESUMO
PURPOSE: While conventional statistical approaches have been used to identify risk factors for cerebrospinal fluid (CSF) shunt failure, these methods may not fully capture the complex contribution of clinical, radiologic, surgical, and shunt-specific variables influencing this outcome. Using prospectively collected data from the Hydrocephalus Clinical Research Network (HCRN) patient registry, we applied machine learning (ML) approaches to create a predictive model of CSF shunt failure. METHODS: Pediatric patients (age < 19 years) undergoing first-time CSF shunt placement at six HCRN centers were included. CSF shunt failure was defined as a composite outcome including requirement for shunt revision, endoscopic third ventriculostomy, or shunt infection within 5 years of initial surgery. Performance of conventional statistical and 4 ML models were compared. RESULTS: Our cohort consisted of 1036 children undergoing CSF shunt placement, of whom 344 (33.2%) experienced shunt failure. Thirty-eight clinical, radiologic, surgical, and shunt-design variables were included in the ML analyses. Of all ML algorithms tested, the artificial neural network (ANN) had the strongest performance with an area under the receiver operator curve (AUC) of 0.71. The ANN had a specificity of 90% and a sensitivity of 68%, meaning that the ANN can effectively rule-in patients most likely to experience CSF shunt failure (i.e., high specificity) and moderately effective as a tool to rule-out patients at high risk of CSF shunt failure (i.e., moderately sensitive). The ANN was independently validated in 155 patients (prospectively collected, retrospectively analyzed). CONCLUSION: These data suggest that the ANN, or future iterations thereof, can provide an evidence-based tool to assist in prognostication and patient-counseling immediately after CSF shunt placement.
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Derivações do Líquido Cefalorraquidiano , Hidrocefalia , Adulto , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Criança , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Lactente , Aprendizado de Máquina , Estudos Retrospectivos , Ventriculostomia , Adulto JovemRESUMO
OBJECTIVES: The majority of the previous literature on clinical predictors of shunt malfunction is from the neurosurgical data, looking at the symptoms of patients who had surgery. Because common childhood illnesses are filtered from these samples, the prevalence of shunt malfunction is markedly higher than it would be for the pediatrician's office or emergency department (ED). Clinical predictive values obtained from a representative population can better inform clinical judgment in these environments. METHODS: A retrospective analysis of the Nationwide Emergency Department Sample (2006-2015) was performed. International Classification of Diseases, Ninth Revision, Clinical Modification Diagnosis/Procedure Codes were used to identify pediatric (≤20 years of age) ED visits with the presence of a cerebrospinal fluid (CSF) shunt (V45.2). Shunt malfunction was defined as any condition resulting in surgical revision (02.41, 02.42, 02.43). Multivariable logistic regression was used to examine the associations between shunt malfunction, demographic factors, and clinical presentation. RESULTS: There were 74,552 observations for ED visits by pediatric patients with a CSF shunt between 2006 and 2015, of which 12.8% (9,560) required shunt revision. Positive predictive values for clinical indicators were reported along with the results of multivariable logistic regression. CONCLUSIONS: We identified peritonitis, papilledema, and oculomotor palsies as the strongest clinical indicators for shunt malfunction in pediatric ED visits with a CSF shunt. We found that patients presenting with headache, nausea/vomiting, convulsions, or fever were more likely to have an etiology other than shunt malfunction. Thus, after an appropriate shunt evaluation, other sources of symptoms should be investigated.
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Derivações do Líquido Cefalorraquidiano , Hidrocefalia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Criança , Serviço Hospitalar de Emergência , Falha de Equipamento , Humanos , Hidrocefalia/cirurgia , Valor Preditivo dos Testes , Estudos RetrospectivosRESUMO
Closed degloving injuries are uncommon, high-energy injuries that separate the bony structures from the soft tissue and frequently result in amputation. Because the epidermis is often intact, it is difficult to visualize the extent of the soft tissue damage. Although there is no gold standard of treatment for closed degloving injuries at present, previous cases have reported that neurovascular presentation is a key predictor of amputation Herein, we report a closed degloving injury involving the second through fifth phalanges of the left foot following a crushing injury with a forklift. Despite adequate capillary refill upon initial presentation, the patient ultimately underwent transmetatarsal amputation.
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Lesões por Esmagamento , Lesões dos Tecidos Moles , Amputação Cirúrgica , Humanos , Lesões dos Tecidos Moles/diagnóstico por imagem , Lesões dos Tecidos Moles/cirurgia , Dedos do Pé/diagnóstico por imagem , Dedos do Pé/lesões , Dedos do Pé/cirurgiaRESUMO
Together, medulloblastoma (MB) and atypical teratoid/rhabdoid tumors (AT/RT) represent two of the most prevalent pediatric brain malignancies. Current treatment involves radiation, which has high risks of developmental sequelae for patients under the age of three. New safer and more effective treatment modalities are needed. Cancer gene therapy is a promising alternative, but there are challenges with using viruses in pediatric patients. We developed a library of poly(beta-amino ester) (PBAE) nanoparticles and evaluated their efficacy for plasmid delivery of a suicide gene therapy to pediatric brain cancer models-specifically herpes simplex virus type I thymidine kinase (HSVtk), which results in controlled apoptosis of transfected cells. In vivo, PBAE-HSVtk treated groups had a greater median overall survival in mice implanted with AT/RT (Pâ¯=â¯0.0083 vs. control) and MB (Pâ¯<â¯0.0001 vs. control). Our data provide proof of principle for using biodegradable PBAE nanoparticles as a safe and effective nanomedicine for treating pediatric CNS malignancies.
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Neoplasias Encefálicas , Terapia Genética , Herpesvirus Humano 1 , Nanopartículas , Timidina Quinase , Proteínas Virais , Animais , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Criança , Herpesvirus Humano 1/enzimologia , Herpesvirus Humano 1/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico , Timidina Quinase/biossíntese , Timidina Quinase/genética , Proteínas Virais/biossíntese , Proteínas Virais/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
INTRODUCTION: Despite folate supplementation, neural tube defects (NTDs) still occur in 0.5-1.0/1,000 pregnancies, with 30-50% not preventable with folate. Twinning has increased due to artificial fertilization and in itself predisposes to NTDs at a rate of 1.6/1,000. The contributions of genetic and environmental factors to myelomeningocele development remain poorly understood. Expression patterns of congenital pathologies in twins can sometimes provide etiological insight. Concordance of NTDs in twins is 0.03/1,000, with dual myelomeningocele reported in only 23 pairs, only one of which survived. We present the 24th pair, the 1st to maintain lower extremity motor function. We review all prior cases and discuss implications of twin concordance on the interplay of genetic and environmental influences. Case Report and Review: A new case of female monozygotic twins born to a well-nourished 24-year-old female is reported with details of perioperative care. Prenatal ultrasound showed L3-S4 and L5-S4 myelomeningoceles, Chiari II malformations, and ventriculomegaly. Copy number microarray was unrevealing. Each underwent uncomplicated repair on day of life 1, and ventriculoperitoneal shunt placement on days of life 10 and 16. Both had movement in the legs upon 6-week follow-up. All prior reported cases of concordant twin myelomeningoceles were abstracted and analyzed, revealing persistence of occurrence despite folate supplementation and a majority occurring in dizygotic pairs. The literature is also reviewed to summarize current knowledge of myelomeningocele pathophysiology as it relates to genetic and environmental influences. DISCUSSION: Meticulous surgical and perioperative care allowed for early positive outcomes in each twin. However, etiopathogenesis remains elusive. In general, only of a minority of cases have underlying genetic lesions or clear environmental triggers. Concordance in monozygotic twins argues for a strong genetic influence; yet, literature review reveals a higher rate of concordant dizygotic twins. This, along with the observation of differing resultant phenotypes in monozygotic twins as seen in this case, prompts further investigation into nonfolate environmental influences. While efforts in genetic investigation should continue, the role of teratogens and exposures should not be minimized in research efforts, public health, and family counseling. Clinical genetic testing remains of limited utility in the majority of patients until more is known.
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Meningomielocele , Defeitos do Tubo Neural , Adulto , Doenças em Gêmeos/genética , Feminino , Humanos , Meningomielocele/genética , Meningomielocele/cirurgia , Gravidez , Gêmeos Dizigóticos , Gêmeos Monozigóticos/genética , Derivação Ventriculoperitoneal , Adulto JovemRESUMO
BACKGROUND: Cultivated hexaploid oat (Common oat; Avena sativa) has held a significant place within the global crop community for centuries; although its cultivation has decreased over the past century, its nutritional benefits have garnered increased interest for human consumption. We report the development of fully annotated, chromosome-scale assemblies for the extant progenitor species of the As- and Cp-subgenomes, Avena atlantica and Avena eriantha respectively. The diploid Avena species serve as important genetic resources for improving common oat's adaptive and food quality characteristics. RESULTS: The A. atlantica and A. eriantha genome assemblies span 3.69 and 3.78 Gb with an N50 of 513 and 535 Mb, respectively. Annotation of the genomes, using sequenced transcriptomes, identified ~ 50,000 gene models in each species-including 2965 resistance gene analogs across both species. Analysis of these assemblies classified much of each genome as repetitive sequence (~ 83%), including species-specific, centromeric-specific, and telomeric-specific repeats. LTR retrotransposons make up most of the classified elements. Genome-wide syntenic comparisons with other members of the Pooideae revealed orthologous relationships, while comparisons with genetic maps from common oat clarified subgenome origins for each of the 21 hexaploid linkage groups. The utility of the diploid genomes was demonstrated by identifying putative candidate genes for flowering time (HD3A) and crown rust resistance (Pc91). We also investigate the phylogenetic relationships among other A- and C-genome Avena species. CONCLUSIONS: The genomes we report here are the first chromosome-scale assemblies for the tribe Poeae, subtribe Aveninae. Our analyses provide important insight into the evolution and complexity of common hexaploid oat, including subgenome origin, homoeologous relationships, and major intra- and intergenomic rearrangements. They also provide the annotation framework needed to accelerate gene discovery and plant breeding.
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Avena/genética , Cromossomos de Plantas/genética , Genoma de Planta , Diploide , Ligação Genética , Anotação de Sequência Molecular , SinteniaRESUMO
We report resonant-cavity infrared detectors with 34% external quantum efficiency at room temperature at the resonant wavelength of 4.0 µm, even though the absorber consists of only five quantum wells with a total thickness of 50 nm. The full width at half maximum (FWHM) linewidth is 46 nm, and the peak absorption is enhanced by nearly a factor of 30 over that for a single pass through the absorber. In spite of an unfavorable Shockley-Read lifetime in the current material, the dark current density is at the level of state-of-the-art HgCdTe detectors as quantified by "Rule 07." The Johnson-noise limited detectivity (D*) at 21°C is 7 × 109 cm Hz½/W. We expect that future improvements in the device design and material quality will lead to higher quantum efficiency, as well as a significant reduction of the dark current density consistent with the very thin absorber.
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OBJECTIVES: To describe the disposition of infants and young children with isolated mild traumatic brain injury and neuroimaging findings evaluated at a level 1 pediatric trauma center, and identify factors associated with their need for ICU admission. DESIGN: Retrospective cohort. SETTING: Single center. PATIENTS: Children less than or equal to 4 years old with mild traumatic brain injury (Glasgow Coma Scale 13-15) and neuroimaging findings evaluated between January 1, 2013, and December 31, 2015. Polytrauma victims and patients requiring intubation or vasoactive infusions preadmission were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two-hundred ten children (median age/weight/Glasgow Coma Scale: 6 mo/7.5 kg/15) met inclusion criteria. Most neuroimaging showed skull fractures with extra-axial hemorrhage/no midline shift (30%), nondisplaced skull fractures (28%), and intracranial hemorrhage without fractures/midline shift (19%). Trauma bay disposition included ICU (48%), ward (38%), intermediate care unit and home (7% each). Overall, 1% required intubation, 4.3% seizure management, and 4.3% neurosurgical procedures; 15% were diagnosed with nonaccidental trauma. None of the ward/intermediate care unit patients were transferred to ICU. Median ICU/hospital length of stay was 2 days. Most patients (99%) were discharged home without neurologic deficits. The ICU subgroup included all patients with midline shift, 62% patients with intracranial hemorrhage, and 20% patients with skull fractures. Across these imaging subtypes, the only clinical predictor of ICU admission was trauma bay Glasgow Coma Scale less than 15 (p = 0.018 for intracranial hemorrhage; p < 0.001 for skull fractures). A minority of ICU patients (18/100) required neurocritical care and/or neurosurgical interventions; risk factors included neurologic deficit, loss of consciousness/seizures, and extra-axial hemorrhage (especially epidural hematoma). CONCLUSIONS: Nearly half of our cohort was briefly monitored in the ICU (with disposition mostly explained by trauma bay imaging, rather than clinical findings); however, less than 10% required ICU-specific interventions. Although ICU could be used for close neuromonitoring to prevent further neurologic injury, additional research should explore if less conservative approaches may preserve patient safety while optimizing healthcare resource utilization.