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1.
Nature ; 607(7919): 527-533, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35794479

RESUMEN

Immature dentate granule cells (imGCs) arising from adult hippocampal neurogenesis contribute to plasticity and unique brain functions in rodents1,2 and are dysregulated in multiple human neurological disorders3-5. Little is known about the molecular characteristics of adult human hippocampal imGCs, and even their existence is under debate1,6-8. Here we performed single-nucleus RNA sequencing aided by a validated machine learning-based analytic approach to identify imGCs and quantify their abundance in the human hippocampus at different stages across the lifespan. We identified common molecular hallmarks of human imGCs across the lifespan and observed age-dependent transcriptional dynamics in human imGCs that suggest changes in cellular functionality, niche interactions and disease relevance, that differ from those in mice9. We also found a decreased number of imGCs with altered gene expression in Alzheimer's disease. Finally, we demonstrated the capacity for neurogenesis in the adult human hippocampus with the presence of rare dentate granule cell fate-specific proliferating neural progenitors and with cultured surgical specimens. Together, our findings suggest the presence of a substantial number of imGCs in the adult human hippocampus via low-frequency de novo generation and protracted maturation, and our study reveals their molecular properties across the lifespan and in Alzheimer's disease.


Asunto(s)
Envejecimiento , Hipocampo , Longevidad , Neurogénesis , Neuronas , Adulto , Envejecimiento/genética , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Proliferación Celular , Giro Dentado/citología , Giro Dentado/patología , Perfilación de la Expresión Génica , Hipocampo/citología , Hipocampo/patología , Humanos , Longevidad/genética , Aprendizaje Automático , Ratones , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Neurogénesis/genética , Neuronas/citología , Neuronas/metabolismo , Neuronas/patología , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcripción Genética
2.
Am J Hum Genet ; 109(12): 2253-2269, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36413998

RESUMEN

Heterozygous pathogenic variants in DNM1 cause developmental and epileptic encephalopathy (DEE) as a result of a dominant-negative mechanism impeding vesicular fission. Thus far, pathogenic variants in DNM1 have been studied with a canonical transcript that includes the alternatively spliced exon 10b. However, after performing RNA sequencing in 39 pediatric brain samples, we find the primary transcript expressed in the brain includes the downstream exon 10a instead. Using this information, we evaluated genotype-phenotype correlations of variants affecting exon 10a and identified a cohort of eleven previously unreported individuals. Eight individuals harbor a recurrent de novo splice site variant, c.1197-8G>A (GenBank: NM_001288739.1), which affects exon 10a and leads to DEE consistent with the classical DNM1 phenotype. We find this splice site variant leads to disease through an unexpected dominant-negative mechanism. Functional testing reveals an in-frame upstream splice acceptor causing insertion of two amino acids predicted to impair oligomerization-dependent activity. This is supported by neuropathological samples showing accumulation of enlarged synaptic vesicles adherent to the plasma membrane consistent with impaired vesicular fission. Two additional individuals with missense variants affecting exon 10a, p.Arg399Trp and p.Gly401Asp, had a similar DEE phenotype. In contrast, one individual with a missense variant affecting exon 10b, p.Pro405Leu, which is less expressed in the brain, had a correspondingly less severe presentation. Thus, we implicate variants affecting exon 10a as causing the severe DEE typically associated with DNM1-related disorders. We highlight the importance of considering relevant isoforms for disease-causing variants as well as the possibility of splice site variants acting through a dominant-negative mechanism.


Asunto(s)
Encefalopatías , Dinaminas , Síndromes Epilépticos , Humanos , Encefalopatías/genética , Causalidad , Dinaminas/genética , Exones/genética , Heterocigoto , Mutación/genética , Síndromes Epilépticos/genética
3.
Childs Nerv Syst ; 40(5): 1361-1366, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38150037

RESUMEN

PURPOSE: Polymorphous low-grade neuroepithelial tumors of the young (PLNTY) represent a rare pediatric-type tumor that most commonly presents as medically refractory epilepsy. PLNTY has only recently been recognized as a distinct clinical entity, having been first described in 2016 and added to the World Health Organization classification of CNS tumors in 2021. Molecular studies have determined that PLNTY is uniformly driven by aberrant MAPK pathway activation, with most tumors carrying either a BRAF V600E mutation or activating FGFR2 or FGFR3 fusion protein. Although it is known that these driver mutations are mutually exclusive, little is known about differences in clinical presentation or treatment outcomes between PLNTY cases driven by these distinct mutations. METHODS: We performed a systematic review and cumulative analysis of PLNTY cases to assess whether or not PLNTY tumors carrying the BRAF V600E mutation exhibit different clinical behaviors. By searching the literature for all cases of PLNTY wherein BRAF V600E status was characterized, we compiled a dataset of 62 unique patient instances. Using a logistic regression-based approach, we assessed a primary outcome of what factors of a clinical presentation were associated with BRAF V600E mutations and a secondary outcome of what factors predicted total seizure freedom post-surgical resection. RESULTS: PLNTY cases carrying BRAF V600E mutations in the literature were strongly positively associated with adult patients (p = 0.0055, OR = 6.556; 95% Conf. Int. = 1.737-24.742). BRAF V600E status was also positively associated with tumor involvement of the temporal lobe (p = 0.0046, OR = 11.036; 95% Conf. Int. = 2.100-58.006). Male sex was also positively associated with BRAF V600E status, but the result did not quite achieve statistical significance (p = 0.0731). BRAF V600E status was not found to be associated with post-operative seizure freedom. CONCLUSIONS: These findings indicate that BRAF V600E-positive PLNTY exhibit characteristic clinical presentations but are not necessarily different in treatment responsiveness. Non-BRAF V600E tumors are more commonly associated with young patients.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Neuroepiteliales , Proteínas Proto-Oncogénicas B-raf , Niño , Humanos , Masculino , Neoplasias Encefálicas/patología , Mutación , Neoplasias Neuroepiteliales/genética , Proteínas Proto-Oncogénicas B-raf/genética , Convulsiones/complicaciones
4.
N Engl J Med ; 380(4): 358-364, 2019 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-30673542

RESUMEN

Conjoined twins who are classified as craniopagus (joined at the cranium) have a rare congenital anomaly. Despite advances in surgical techniques and critical care, the rate of complications and death is still high among twins with total fusion in which the superior sagittal sinus is shared. Here, we describe total-fusion craniopagus twins who at 10 months of age underwent successful surgical separation performed by a multidisciplinary team. Computer-aided design and modeling with a three-dimensional printer, custom-designed cranial distraction and constriction devices, and intraoperative navigation techniques were used. These techniques allowed for separation of the twins at an early age and harnessed the regenerative capacity of their young brains.


Asunto(s)
Osteogénesis por Distracción , Cráneo/cirugía , Gemelos Siameses/cirugía , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Encéfalo/cirugía , Angiografía Cerebral , Femenino , Humanos , Lactante , Procedimientos de Cirugía Plástica/métodos , Cráneo/diagnóstico por imagen , Seno Sagital Superior/cirugía , Tomografía Computarizada por Rayos X
5.
Neurosurg Focus ; 53(4): E3, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36183186

RESUMEN

OBJECTIVE: Stereoelectroencephalography (SEEG) is a widely used technique for localizing seizure onset zones prior to resection. However, its use has traditionally been avoided in children under 2 years of age because of concerns regarding pin fixation in the immature skull, intraoperative and postoperative electrode bolt security, and stereotactic registration accuracy. In this retrospective study, the authors describe their experience using SEEG in patients younger than 2 years of age, with a focus on the procedure's safety, feasibility, and accuracy as well as surgical outcomes. METHODS: A retrospective review of children under 2 years of age who had undergone SEEG while at Children's Hospital of Philadelphia between November 2017 and July 2021 was performed. Data on clinical characteristics, surgical procedure, imaging results, electrode accuracy measurements, and postoperative outcomes were examined. RESULTS: Five patients younger than 2 years of age underwent SEEG during the study period (median age 20 months, range 17-23 months). The mean age at seizure onset was 9 months. Developmental delay was present in all patients, and epilepsy-associated genetic diagnoses included tuberous sclerosis (n = 1), KAT6B (n = 1), and NPRL3 (n = 1). Cortical lesions included tubers from tuberous sclerosis (n = 1), mesial temporal sclerosis (n = 1), and cortical dysplasia (n = 3). The mean number of placed electrodes was 11 (range 6-20 electrodes). Bilateral electrodes were placed in 1 patient. Seizure onset zones were identified in all cases. There were no SEEG-related complications, including skull fracture, electrode misplacement, hemorrhage, infection, cerebrospinal fluid leakage, electrode pullout, neurological deficit, or death. The mean target point error for all electrodes was 1.0 mm. All patients proceeded to resective surgery, with a mean follow-up of 21 months (range 8-53 months). All patients attained a favorable epilepsy outcome, including Engel class IA (n = 2), IC (n = 1), ID (n = 1), and IIA (n = 1). CONCLUSIONS: SEEG can be safely, accurately, and effectively utilized in children under age 2 with good postoperative outcomes using standard SEEG equipment. With minimal modification, this procedure is feasible in those with immature skulls and guides the epilepsy team's decision-making for early and optimal treatment of refractory epilepsy through effective localization of seizure onset zones.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Esclerosis Tuberosa , Niño , Preescolar , Epilepsia Refractaria/cirugía , Electrodos Implantados , Electroencefalografía/métodos , Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Proteínas Activadoras de GTPasa , Histona Acetiltransferasas , Humanos , Lactante , Estudios Retrospectivos , Convulsiones/cirugía , Técnicas Estereotáxicas , Esclerosis Tuberosa/cirugía
6.
J Pediatr ; 236: 54-61.e1, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34004191

RESUMEN

OBJECTIVE: To demonstrate that a novel noninvasive index of intracranial pressure (ICP) derived from diffuse optics-based techniques is associated with intracranial hypertension. STUDY DESIGN: We compared noninvasive and invasive ICP measurements in infants with hydrocephalus. Infants born term and preterm were eligible for inclusion if clinically determined to require cerebrospinal fluid (CSF) diversion. Ventricular size was assessed preoperatively via ultrasound measurement of the fronto-occipital (FOR) and frontotemporal (FTHR) horn ratios. Invasive ICP was obtained at the time of surgical intervention with a manometer. Intracranial hypertension was defined as invasive ICP ≥15 mmHg. Diffuse optical measurements of cerebral perfusion, oxygen extraction, and noninvasive ICP were performed preoperatively, intraoperatively, and postoperatively. Optical and ultrasound measures were compared with invasive ICP measurements, and their change in values after CSF diversion were obtained. RESULTS: We included 39 infants, 23 with intracranial hypertension. No group difference in ventricular size was found by FOR (P = .93) or FTHR (P = .76). Infants with intracranial hypertension had significantly higher noninvasive ICP (P = .02) and oxygen extraction fraction (OEF) (P = .01) compared with infants without intracranial hypertension. Increased cerebral blood flow (P = .005) and improved OEF (P < .001) after CSF diversion were observed only in infants with intracranial hypertension. CONCLUSIONS: Noninvasive diffuse optical measures (including a noninvasive ICP index) were associated with intracranial hypertension. The findings suggest that impaired perfusion from intracranial hypertension was independent of ventricular size. Hemodynamic evidence of the benefits of CSF diversion was seen in infants with intracranial hypertension. Noninvasive optical techniques hold promise for aiding the assessment of CSF diversion timing.


Asunto(s)
Circulación Cerebrovascular/fisiología , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/fisiopatología , Hipertensión Intracraneal/diagnóstico , Derivaciones del Líquido Cefalorraquídeo , Estudios de Factibilidad , Femenino , Humanos , Hidrocefalia/cirugía , Recién Nacido , Hipertensión Intracraneal/etiología , Hipertensión Intracraneal/fisiopatología , Presión Intracraneal/fisiología , Masculino , Imagen Óptica , Proyectos Piloto , Reproducibilidad de los Resultados , Análisis Espectral
7.
Childs Nerv Syst ; 37(7): 2153-2161, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33907902

RESUMEN

PURPOSE: Several variations of functional disconnection surgery have been described for the treatment of lateralized, hemispheric, drug-resistant epilepsy in children. The purpose of this study is to investigate the existing literature regarding patient selection, approach, and outcomes after hemispherotomy. METHODS: A systematic review of the English literature through February 2019 was performed in accordance with the PRISMA statement. The articles were classified by level of evidence and summarized in an evidentiary table. Seizure outcomes, functional outcomes, surgical techniques, complications, and patient selection were critically analyzed. RESULTS: A total of 173 papers were reviewed, of which 37 met criteria of inclusion and exclusion. Thirteen studies were classified as level III evidence, the remaining reached level IV. Vertical and lateral hemispherotomy achieve similar rates of seizure freedom and functional outcomes, though parasagittal and interhemispheric approaches may have shorter operative times and less blood loss. Etiology, bilateral MRI abnormalities, and nonlateralizing EEG did not predict worse seizure or functional outcomes. CONCLUSIONS: Both vertical and lateral hemispherotomy approaches result in durable, reproducible benefits to epilepsy severity and functional status in appropriately selected pediatric patients.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Hemisferectomía , Niño , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/cirugía , Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Humanos , Convulsiones/cirugía , Resultado del Tratamiento
8.
Epilepsia ; 60(5): 898-910, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31006860

RESUMEN

OBJECTIVE: Interictal spikes are a characteristic feature of invasive electroencephalography (EEG) recordings in children with refractory epilepsy. Spikes frequently co-occur across multiple brain regions with discernable latencies, suggesting that spikes can propagate through distributed neural networks. The purpose of this study was to examine the long-term reproducibility of spike propagation patterns over hours to days of interictal recording. METHODS: Twelve children (mean age 13.1 years) were retrospectively studied. A mean ± standard deviation (SD) of 47.2 ± 40.1 hours of interictal EEG recordings were examined per patient (range 17.5-166.5 hours). Interictal recordings were divided into 30-minute segments. Networks were extracted based on the frequency of spike coactivation between pairs of electrodes. For each 30-minute segment, electrodes were assigned a "Degree Preference (DP)" based on the tendency to appear upstream or downstream within propagation sequences. The consistency of DPs across segments ("DP-Stability") was quantified using the Spearman rank correlation. RESULTS: Regions exhibited highly stable preferences to appear upstream, intermediate, or downstream in spike propagation sequences. Across networks, the mean ± SD DP-Stability was 0.88 ± 0.07, indicating that propagation patterns observed in 30-minute segments were representative of the patterns observed in the full interictal window. At the group level, regions involved in seizure generation appeared more upstream in spike propagation sequences. SIGNIFICANCE: Interictal spike propagation is a highly reproducible output of epileptic networks. These findings shed new light on the spatiotemporal dynamics that may constrain the network mechanisms of refractory epilepsy.


Asunto(s)
Epilepsia Refractaria/fisiopatología , Electroencefalografía , Red Nerviosa/fisiopatología , Adolescente , Niño , Epilepsia Refractaria/terapia , Terapia por Estimulación Eléctrica , Electrodos Implantados , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos , Espacio Subdural
9.
Childs Nerv Syst ; 35(11): 2187-2194, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31267182

RESUMEN

PURPOSE: Children with myelomeningocele (MMC) are at increased risk of developing neuromuscular scoliosis and spinal cord re-tethering (Childs Nerv Syst 12:748-754, 1996; Neurosurg Focus 16:2, 2004; Neurosurg Focus 29:1, 2010). Some centers perform prophylactic untethering on asymptomatic MMC patients prior to scoliosis surgery because of concern that additional traction on the cord may place the patient at greater risk of neurologic deterioration peri-operatively. However, prophylactic untethering may not be justified if it carries increased surgical risks. The purpose of this study was to determine if prophylactic untethering is necessary in asymptomatic children with MMC undergoing scoliosis surgery. METHODS: A multidisciplinary, retrospective cohort study from seven children's hospitals was performed including asymptomatic children with MMC < 21 years old, managed with or without prophylactic untethering prior to scoliosis surgery. Patients were divided into three groups for analysis: (1) untethering at the time of scoliosis surgery (concomitant untethering), (2) untethering within 3 months of scoliosis surgery (prior untethering), and (3) no prophylactic untethering. Baseline data, intra-operative reports, and 90-day post-operative outcomes were analyzed to assess for differences in neurologic outcomes, surgical complications, and overall length of stay. RESULTS: A total of 208 patients were included for analysis (mean age 9.4 years, 52% girls). No patient in any of the groups exhibited worsened motor or sensory function at 90 days post-operatively. However, comparing the prophylactic untethering groups with the group that was not untethered, there was an increased risk of surgical site infection (SSI) (31.3% concomitant, 28.6% prior untethering vs. 12.3% no untethering; p = 0.0104), return to the OR (43.8% concomitant, 23.8% prior untethering vs. 17.4% no untethering; p = 0.0047), need for blood transfusion (51.6% concomitant, 57.1% prior untethering vs. 33.8% no untethering; p = 0.04), and increased mean length of stay (LOS) (13.4 days concomitant, 10.6 days prior untethering vs. 6.8 days no untethering; p < 0.0001). In multivariable logistic regression analysis, prophylactic untethering was independently associated with increased adjusted relative risks of surgical site infection (aRR = 2.65, 95% CI 1.17-5.02), unplanned re-operation (aRR = 2.17, 95% CI 1.02-4.65), and any complication (aRR = 2.25, 95% CI 1.07-4.74). CONCLUSION: In this study, asymptomatic children with myelomeningocele who underwent scoliosis surgery developed no neurologic injuries regardless of prophylactic untethering. However, those who underwent prophylactic untethering were more likely to experience SSIs, return to the OR, need a blood transfusion, and have increased LOS than children not undergoing untethering. Based on these data, prophylactic untethering in asymptomatic MMC patients prior to scoliosis surgery does not provide any neurological benefit and is associated with increased surgical risks.


Asunto(s)
Transfusión Sanguínea/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Meningomielocele/cirugía , Procedimientos Quirúrgicos Profilácticos , Escoliosis/cirugía , Enfermedades de la Médula Espinal/cirugía , Infección de la Herida Quirúrgica/epidemiología , Adolescente , Enfermedades Asintomáticas , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Meningomielocele/complicaciones , Análisis Multivariante , Defectos del Tubo Neural/cirugía , Procedimientos Neuroquirúrgicos , Complicaciones Posoperatorias/epidemiología , Reoperación/estadística & datos numéricos , Escoliosis/etiología , Enfermedades de la Médula Espinal/etiología
10.
Neurosurg Focus ; 47(2): E4, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31370025

RESUMEN

OBJECTIVE: External ventricular drains (EVDs) are commonly used in the neurosurgical population. However, very few pediatric neurosurgery studies are available regarding EVD-associated infection rates with antibiotic-impregnated EVD catheters. The authors previously published a large pediatric cohort study analyzing nonantibiotic-impregnated EVD catheters and risk factors associated with infections. In this study, they aimed to analyze the EVD-associated infection rate after implementation of antibiotic-impregnated EVD catheters. METHODS: A retrospective observational cohort of pediatric patients (younger than 18 years of age) who underwent a burr hole for antibiotic-impregnated EVD placement and who were admitted to a quaternary care ICU between January 2011 and January 2019 were reviewed. The ventriculostomy-associated infection rate in patients with antibiotic-impregnated EVD catheters was compared to the authors' historical control of patients with nonantibiotic-impregnated EVD catheters. RESULTS: Two hundred twenty-nine patients with antibiotic-impregnated EVD catheters were identified. Neurological diagnostic categories included externalization of an existing shunt (externalized shunt) in 34 patients (14.9%); brain tumor (tumor) in 77 patients (33.6%); intracranial hemorrhage (ICH) in 27 patients (11.8%); traumatic brain injury (TBI) in 6 patients (2.6%); and 85 patients (37.1%) were captured in an "other" category. Two of 229 patients (0.9% of all patients) had CSF infections associated with EVD management, totaling an infection rate of 0.99 per 1000 catheter days. This is a significantly lower infection rate than was reported in the authors' previously published analysis of the use of nonantibiotic-impregnated EVD catheters (0.9% vs 6%, p = 0.00128). CONCLUSIONS: In their large pediatric cohort, the authors demonstrated a significant decline in ventriculostomy-associated CSF infection rate after implementation of antibiotic-impregnated EVD catheters at their institution.


Asunto(s)
Antibacterianos/uso terapéutico , Catéteres/efectos adversos , Derivaciones del Líquido Cefalorraquídeo/efectos adversos , Ventriculostomía/efectos adversos , Adolescente , Niño , Preescolar , Estudios de Cohortes , Drenaje/efectos adversos , Femenino , Humanos , Lactante , Infecciones/líquido cefalorraquídeo , Infecciones/tratamiento farmacológico , Masculino , Procedimientos Neuroquirúrgicos/efectos adversos , Estudios Retrospectivos
11.
J Zoo Wildl Med ; 50(1): 127-136, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31120671

RESUMEN

Tarantulas are a commonly kept species that are occasionally presented to veterinarians in exotic practice. A recent study on Grammastola rosea hemolymph biochemistry has been performed with nonanesthetized adult theraphosids. The objective of this study was to produce reference intervals for biochemistry biomarkers in hemolymph of chemically restrained G. rosea for use diagnostically by exotic veterinarians. Cardiac hemolymph collection was performed on 20 subadult tarantulas under general anesthesia with isoflurane. Samples were processed by a commercial laboratory. Statistics performed on the data include outlier exclusion, descriptive statistics, normality tests, and Pearson correlations. Reference intervals were made for total protein, creatine kinase (CK), aspartate aminotransferase (AST), glucose, uric acid (UA), calcium, and phosphorus. No cortisol was detected. The majority of the intervals produced were normally distributed with the exceptions of UA, phosphorus, and CK. Pearson correlation tests found several significant (P = <0.05) correlations between variables. The majority of the data displayed a normal distribution, unlike the previous study, with a greater number of replicates. The total protein, glucose, UA, calcium, and AST values generated were similar to those reported in the previous study. Conversely several variables such as phosphorus, CK, and albumin were not consistent with those previously reported. Evidence is presented for a lack of albumin, CK, and AST in Arachnida and thus previous data for these proteins is likely to be artifactual.


Asunto(s)
Anestésicos Generales/administración & dosificación , Hemolinfa/química , Isoflurano/administración & dosificación , Arañas/química , Anestesia General/veterinaria , Animales , Análisis Químico de la Sangre/veterinaria , Valores de Referencia , Arañas/efectos de los fármacos
12.
Blood ; 124(20): 3101-9, 2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25170122

RESUMEN

B-cell receptor (BCR) signaling plays a key role in the behavior of chronic lymphocytic leukemia (CLL). However, cellular consequences of signaling are incompletely defined. Here we explored possible links between BCR signaling and the unfolded protein response (UPR), a stress response pathway that can promote survival of normal and malignant cells. Compared with normal B cells, circulating CLL cells expressed increased, but variable, levels of UPR components. Higher expression of CHOP and XBP1 RNAs was associated with more aggressive disease. UPR activation appeared due to prior tissue-based antigenic stimulation because elevated expression of UPR components was detected within lymph node proliferation centers. Basal UPR activation also correlated closely with surface immunoglobulin M (sIgM) signaling capacity in vitro in both IGHV unmutated CLL and within mutated CLL. sIgM signaling increased UPR activation in vitro with responders showing increased expression of CHOP and XBP1 RNAs, and PERK and BIP proteins, but not XBP1 splicing. Inhibitors of BCR-associated kinases effectively prevented sIgM-induced UPR activation. Overall, this study demonstrates that sIgM signaling results in activation of some components the UPR in CLL cells. Modulation of the UPR may contribute to variable clinical behavior, and its inhibition may contribute to clinical responses to BCR-associated kinase inhibitors.


Asunto(s)
Linfocitos B/inmunología , Inmunoglobulina M/inmunología , Péptidos y Proteínas de Señalización Intracelular/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Proteínas Tirosina Quinasas/inmunología , Receptores de Antígenos de Linfocitos B/inmunología , Respuesta de Proteína Desplegada , Agammaglobulinemia Tirosina Quinasa , Linfocitos B/patología , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Transducción de Señal , Quinasa Syk
13.
Childs Nerv Syst ; 32(3): 531-4, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26758882

RESUMEN

INTRODUCTION: Syrinx has been reported in 25-85 % of children with Chiari malformation type I (CMI), and it is most commonly cervical in location. As a result, cervical MRI is routinely included in an evaluation for CMI. Isolated thoracic syrinx without involvement of the cervical cord in this population is uncommon but clinically important because its presence may influence the decision to operate, surgical techniques employed, or interpretation of follow-up imaging. The purpose of this study was to determine the incidence of isolated thoracic syrinx in a large group of children evaluated for CMI. METHODS: We retrospectively reviewed all patients under 21 years of age who were evaluated for CMI at Columbia University/Morgan Stanley Children's Hospital of New York from 1998 to 2013. All patients underwent MRI of the entire spine as part of the CMI evaluation, regardless of whether surgery was planned. The proportion of patients exhibiting isolated thoracic syrinx was determined. Presenting signs, symptoms, and imaging findings were then studied in an attempt to identify any clinical features associated with isolated thoracic syrinx. RESULTS: We identified 266 patients evaluated over the study period. One-hundred thirty-two patients (50 %) presented with a syrinx, and 12 patients (4.5 % of all patients evaluated and 9.1 % of all patients with a syrinx) had an isolated thoracic syrinx. Demographic variables, clinical presentation, and extent of tonsillar ectopia showed great heterogeneity in this group, and no factor was consistently associated with isolated thoracic syrinx. CONCLUSIONS: Isolated thoracic syrinx is an uncommon but clinically significant finding in children with CMI. Our data demonstrate that the presence of a CMI-related thoracic syrinx cannot be reliably predicted clinically and is therefore likely to be missed in patients who do not undergo complete spinal cord imaging. MRI of the entire spinal cord should be considered for all children undergoing initial evaluation for CMI.


Asunto(s)
Malformación de Arnold-Chiari/complicaciones , Siringomielia/complicaciones , Siringomielia/epidemiología , Vértebras Torácicas/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos
14.
Childs Nerv Syst ; 32(4): 697-701, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26458905

RESUMEN

Endoscopic third ventriculostomy with choroid plexus cauterization (ETV/CPC) as a primary treatment for hydrocephalus is gaining popularity in North America, particularly among the infant population. Unfortunately, despite considerable experience with ETV/CPC at several centers, treatment failures still exist. Early reports have suggested that greater than 90 % cauterization of the choroid plexus is associated with improved clinical outcomes. However, individual patient anatomy and smaller overall ventricular size can limit the amount of choroid plexus cauterization that is technically possible through a single frontal burr hole. Furthermore, the degree of cauterization achieved by surgeons using this technique is difficult to quantify objectively. In this report, we describe the case of an infant who failed initial ETV/CPC but then had successful resolution of hydrocephalus after additional choroid plexus cauterization performed through bilateral occipital burr holes. The child remains shunt-free over a year after treatment, suggesting that this three-pronged CPC approach (the "bowling ball" technique) may be successful in some young children with persistent hydrocephalus after ETV/CPC from a single frontal burr hole.


Asunto(s)
Cauterización/métodos , Plexo Coroideo/cirugía , Hidrocefalia/cirugía , Tercer Ventrículo/cirugía , Ventriculostomía/métodos , Adolescente , Plexo Coroideo/diagnóstico por imagen , Femenino , Humanos , Hidrocefalia/diagnóstico por imagen , Imagen por Resonancia Magnética , Tercer Ventrículo/diagnóstico por imagen
15.
Stereotact Funct Neurosurg ; 93(6): 415-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26756899

RESUMEN

BACKGROUND: Ommaya reservoirs are ventricular access devices used primarily for the administration of intrathecal antineoplastic chemotherapy. In patients with low or normal ventricular volume, stereotaxy can improve accuracy of catheter placement with minimal morbidity. Frameless stereotaxy has become an increasingly popular alternative to frame-based stereotaxy. Relative rates of successful catheter placement between these two techniques are not described in the literature. OBJECTIVES: To compare a large series of frameless to frame-based stereotactic catheter placements for Ommaya reservoirs, with an aim to compare accuracy and complication rate between the two procedures. METHODS: A consecutive series of 41 frame-based and 68 frameless Ommaya reservoir placement procedures performed at our institution from 1998 to 2013 was reviewed. Patient demographics, operative accuracy and complication rates for the two techniques were compared. RESULTS: Characteristics of the two groups were similar in diagnoses, age and other related factors. Comparison of frameless to frame-based stereotactic Ommaya catheter placement did not show significant differences in accuracy of placement, overall morbidity or mortality, or in any subcategory of complications. CONCLUSIONS: These findings suggest that frameless stereotactic Ommaya reservoir placement is as safe and accurate as the frame-based technique.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Neuronavegación/métodos , Técnicas Estereotáxicas/instrumentación , Sistemas de Liberación de Medicamentos/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuronavegación/instrumentación
16.
J Neurooncol ; 119(3): 451-63, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24969924

RESUMEN

Modern glioma surgery has evolved around the central tenet of safely maximizing resection. Recent surgical adjuncts have focused on increasing the maximum extent of resection while minimizing risk to functional brain. Technologies such as cortical and subcortical stimulation mapping, intraoperative magnetic resonance imaging, functional neuronavigation, navigable intraoperative ultrasound, neuroendoscopy, and fluorescence-guided resection have been developed to augment the identification of tumor while preserving brain anatomy and function. However, whether these technologies offer additional long-term benefits to glioma patients remains to be determined. Here we review advances over the past decade in operative technologies that have offered the most promising benefits for glioblastoma patients.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioblastoma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Cirugía Asistida por Computador/métodos , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/patología , Glioblastoma/patología , Humanos
17.
Neurosurg Focus ; 36(1): E12, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24380478

RESUMEN

OBJECT: Pediatric patients with sickle cell anemia (SCA) carry a significant risk of developing moyamoya syndrome (MMS) and brain ischemia. The authors sought to review the safety and efficacy of pial synangiosis in the treatment of MMS in children with SCA by performing a comprehensive review of all previously reported cases in the literature. METHODS: The authors retrospectively reviewed the clinical and radiographic records in 17 pediatric patients with SCA treated at the Morgan Stanley Children's Hospital of New York (MSCHONY) who developed radiological evidence of MMS and underwent pial synangiosis between 1996 and 2012. The authors then added any additional reported cases of pial synangiosis for this population in the literature for a combined analysis of clinical and radiographic outcomes. RESULTS: The combined data consisted of 48 pial synangiosis procedures performed in 30 patients. Of these, 27 patients (90%) presented with seizure, stroke, or transient ischemic attack, whereas 3 (10%) were referred after transcranial Doppler screening. At the time of surgery, the median age was 12 years. Thirteen patients (43%) suffered an ischemic stroke while on chronic transfusion therapy. Long-term follow-up imaging (MR angiography or catheter angiography) at a mean of 25 months postoperatively was available in 39 (81%) treated hemispheres. In 34 (87%) of those hemispheres there were demonstrable collateral vessels on imaging. There were 4 neurological events in 1590 cumulative months of follow-up, or 1 event per 33 patient-years. In the patients in whom complete data were available (MSCHONY series, n = 17), the postoperative stroke rate was reduced more than 6-fold from the preoperative rate (p = 0.0003). CONCLUSIONS: Pial synangiosis in patients with SCA, MMS, and brain ischemia appears to be a safe and effective treatment option. Transcranial Doppler and/or MRI screening in asymptomatic patients with SCA is recommended for the diagnosis of MMS.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Venas Cerebrales/cirugía , Enfermedad de Moyamoya/cirugía , Procedimientos Neuroquirúrgicos/métodos , Adolescente , Anemia de Células Falciformes/fisiopatología , Isquemia Encefálica/cirugía , Angiografía Cerebral , Niño , Estudios de Cohortes , Femenino , Humanos , Ataque Isquémico Transitorio/etiología , Ataque Isquémico Transitorio/cirugía , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Enfermedad de Moyamoya/diagnóstico por imagen , Procedimientos Neuroquirúrgicos/efectos adversos , Complicaciones Posoperatorias/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Resultado del Tratamiento , Adulto Joven
18.
Curr Probl Pediatr Adolesc Health Care ; 54(7): 101575, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38395641

RESUMEN

While recent technological advancements are reshaping the landscape of surgical epilepsy management, the established techniques of resective and disconnective surgeries guided by electrographic monitoring remain the workhorse interventions for the management of refractory seizures and have the highest likelihood of achieving complete seizure resolution. Here we discuss examples of recent developments in surgical approaches and techniques for resective and disconnective surgeries with discussion of their indications and potential advantages.


Asunto(s)
Procedimientos Neuroquirúrgicos , Niño , Humanos , Epilepsia Refractaria/cirugía , Electroencefalografía , Epilepsia/cirugía , Procedimientos Neuroquirúrgicos/métodos
19.
Mol Genet Genomic Med ; 12(5): e2436, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38738460

RESUMEN

BACKGROUND: Trisomy 20p is a rare genetic condition caused by a duplication of the short arm of chromosome 20. METHODS: We employed clinical observation and molecular genetic testing (SNP microarray), to study identical twin males with an unknown dysmorphic syndrome. We conducted a literature review of trisomy 20p and collated the clinical and molecular genetic findings on 20 affected subjects reported since 2000. RESULTS: Identical twin males, whose prenatal course was complicated by a twin-to-twin transfusion, manifested profound language and neurocognitive delays as well as distinctive facial dysmorphisms when evaluated at 2 years of age. SNP microarray identified identical duplications of 20p13 with no other chromosomal aberrations. A literature survey of 20p trisomy syndrome identified 20 other examples of this condition reported since 2000, which we collated with 33 summarized by Sidwell et al. (2000). Within the combined total of 55 affected individuals, we found a distinctive clinical phenotype that provides insight on the effects of abnormal dosage of genes in 20p13. These loci include FAM110A (OMIM 611393), ANGPT4 (OMIM 603705), RSPO4 (OMIM 610573), PSMF1 (OMIM 617858), SNPH (OMIM 604942), SDCBP2 (OMIM 617358), FKBP1A (OMIM 186945), TMEM74B, C20orf202, and RAD21L1 (OMIM 619533). Gene profiling highlighted that syntaphilin (SNPH) is highly expressed in mammalian brain, where it is considered critical for mitochondrial transport in neuronal axons, and to directly influence axonal morphogenesis and function. CONCLUSION: We propose that abnormal activity of syntaphilin engendered by the trisomy is primarily responsible for the language, neurocognitive, and gross motor delays reported in individuals with 20p trisomy. Additional studies, for example, characterization of cerebral organoids generated from affected patients may help to better understand this condition, and potentially suggest rational remedies to improve the lives of affected individuals and their families.


Asunto(s)
Trisomía , Humanos , Masculino , Trisomía/genética , Duplicación Cromosómica , Preescolar , Gemelos Monocigóticos/genética , Polimorfismo de Nucleótido Simple
20.
Artículo en Inglés | MEDLINE | ID: mdl-38953672

RESUMEN

The transpalpebral approach provides a minimally invasive corridor to the anterior skull base and temporal lobe. It has been described for anterior circulation aneurysms and skull base tumors as well as more recently for resection of epileptogenic pathology in the adult population. We describe our experience using this approach in a 13-year-old adolescent boy suffering from epilepsy secondary to concomitant left temporal focal cortical dysplasia and pleomorphic xanthoastrocytoma extending throughout the amygdala with excellent results.1-5 To the best of our knowledge, this is the first published case using the transpalpebral approach for this pathology, as well for epilepsy in the pediatric population. The patient consented to the procedure and to the publication of his image.

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