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1.
Nat Commun ; 14(1): 6279, 2023 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-37805627

RESUMEN

Hedgehog signaling mediates embryologic development of the central nervous system and other tissues and is frequently hijacked by neoplasia to facilitate uncontrolled cellular proliferation. Meningiomas, the most common primary brain tumor, exhibit Hedgehog signaling activation in 6.5% of cases, triggered by recurrent mutations in pathway mediators such as SMO. In this study, we find 35.6% of meningiomas that lack previously known drivers acquired various types of somatic structural variations affecting chromosomes 2q35 and 7q36.3. These cases exhibit ectopic expression of Hedgehog ligands, IHH and SHH, respectively, resulting in Hedgehog signaling activation. Recurrent tandem duplications involving IHH permit de novo chromatin interactions between super-enhancers within DIRC3 and a locus containing IHH. Our work expands the landscape of meningioma molecular drivers and demonstrates enhancer hijacking of Hedgehog ligands as a route to activate this pathway  in neoplasia.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Meningioma/genética , Ligandos , Transducción de Señal , Neoplasias Meníngeas/genética
2.
Radiol Case Rep ; 17(5): 1470-1474, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35265242

RESUMEN

Dural arteriovenous fistulae of the middle meningeal artery (MMA-dAVF) are high risk lesions that can lead to intracranial hemorrhage. We describe the case of an adult male that presented with chronic subdural hematomas and was treated with burr hole craniotomy plus middle meningeal artery (MMA) embolization. Although the pre-embolization angiogram showed no signs of a fistula, a fistula arising from the MMA and draining into the superior sagittal sinus emerged intra-operatively. To our knowledge, this is the first case of intra-operative emergence of occult MMA-dAVF with intracranial drainage during MMA embolization for chronic subdural hematoma treatment. This observation supports monitoring for and embolizing spontaneous MMA-dAVF following MMA embolization.

3.
J Neurosurg Case Lessons ; 2(10): CASE21361, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-35855183

RESUMEN

BACKGROUND: Juvenile psammomatoid ossifying fibroma (JPOF) is an uncommon benign fibro-osseous lesion that only rarely presents in the calvaria. OBSERVATIONS: The authors reported a case of JPOF in the left parietal bone of a 20-year-old patient and reviewed the 27 other cases of JPOF occurring in the calvaria as reported in the literature. LESSONS: JPOF rarely presents in the calvaria, and because diagnosis is a histopathologic one, clinicians should consider this entity when presented with a lytic, expansile mass on imaging. Little is known about the molecular mechanisms driving development of JPOF. MDM2 amplification may play a role, although this was not seen in the case presented herein.

4.
Neuro Oncol ; 23(5): 783-794, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33068421

RESUMEN

BACKGROUND: We and others have identified mutually exclusive molecular subgroups of meningiomas; however, the implications of this classification for clinical prognostication remain unclear. Integrated genomic and epigenomic analyses implicate unique oncogenic processes associated with each subgroup, suggesting the potential for divergent clinical courses. The aim of this study was to understand the associated clinical outcomes of each subgroup, as this could optimize treatment for patients. METHODS: We analyzed outcome data for 469 meningiomas of known molecular subgroup, including extent of resection, postoperative radiation, surveillance imaging, and time to recurrence, when applicable. Statistical relationships between outcome variables and subgroup were assessed. Features previously associated with recurrence were further investigated after stratification by subgroup. We used Kaplan-Meier analyses to compare progression-free survival, and identified factors significantly associated with recurrence using Cox proportional hazards modeling. RESULTS: Meningioma molecular subgroups exhibited divergent clinical courses at 2 years of follow-up, with several aggressive subgroups (NF2, PI3K, HH, tumor necrosis factor receptor-associated factor 7 [TRAF7]) recurring at an average rate of 22 times higher than others (KLF4, POLR2A, SMARCB1). PI3K-activated tumors recurred earlier than other subgroups but had intermediate long-term outcome. Among low-grade tumors, HH and TRAF7 meningiomas exhibited elevated recurrence compared with other subgroups. Recurrence of NF2 tumors was associated with male sex, high grade, and elevated Ki-67. Multivariate analysis identified molecular subgroup as an independent predictor of recurrence, along with grade and previous recurrence. CONCLUSION: We describe distinct clinical outcomes and recurrence rates associated with meningioma molecular subgroups. Our findings emphasize the importance of genomic characterization to guide postoperative management decisions for meningiomas.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Epigenómica , Genómica , Humanos , Factor 4 Similar a Kruppel , Masculino , Neoplasias Meníngeas/genética , Meningioma/genética , Recurrencia Local de Neoplasia/genética , Estudios Retrospectivos
5.
Global Spine J ; 9(3): 331-337, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31192102

RESUMEN

STUDY DESIGN: Narrative review. OBJECTIVES: To discuss the relationship between degenerative cervical myelopathy (DCM) and vitamin B12 deficiency. Specifically, it is the aim to outline the rational for future research into assessment and therapeutic optimization of vitamin B12 in the treatment of DCM. METHODS: Literature review. RESULTS: DCM is the commonest cause of spinal cord impairment, with an average age of presentation in the sixth decade. Patients at this age have also been reported to have a high prevalence of vitamin B12 deficiency, with estimates of up to 20% in the elderly. Vitamin B12 deficiency can result in subacute combined degeneration of the spinal cord (SACD), and several case reports have pointed to patients with both DCM and SACD. Both SACD and reversible compressive injury due to DCM necessitate remyelination in the spinal cord, a process that requires adequate vitamin B12 levels. Basic science research on nerve crush injuries have shown that vitamin B12 levels are altered after nerve injury and that vitamin B12 along with dexamethasone or nonsteroidal anti-inflammatory drugs can reduce Wallerian degeneration. Furthermore, it has been suggested that a combination of B-vitamins can reduce glutamate-induced neurotoxicity. CONCLUSIONS: Given the high prevalence of clinical and subclinical vitamin B12 deficiency in the elderly, the role of vitamin B12 in myelination, and vitamin B12 deficiency as a differential diagnosis of DCM, it is important to investigate what role vitamin B12 levels play in patients with DCM in terms of baseline neurological function and whether optimization of vitamin B12 levels can improve surgical outcome. Furthermore, the routine assessment of vitamin B12 levels in patients considered for DCM surgery should be considered.

6.
J Clin Med ; 8(10)2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31547030

RESUMEN

Spinal disorders and associated interventions are costly in the United States, putting them in the limelight of economic analyses. The Patient-Reported Outcomes Measurement Information System Global Health Survey (PROMIS-GHS) requires mapping to other surveys for economic investigation. Previous studies have proposed transformations of PROMIS-GHS to EuroQol 5-Dimension (EQ-5D) health index scores. These models require validation in adult spine patients. In our study, PROMIS-GHS and EQ-5D were randomly administered to 121 adult spine patients. The actual health index scores were calculated from the EQ-5D instrument and estimated scores were calculated from the PROMIS-GHS responses with six models. Goodness-of-fit for each model was determined using the coefficient of determination (R2), mean squared error (MSE), and mean absolute error (MAE). Among the models, the model treating the eight PROMIS-GHS items as categorical variables (CATReg) was the optimal model with the highest R2 (0.59) and lowest MSE (0.02) and MAE (0.11) in our spine sample population. Subgroup analysis showed good predictions of the mean EQ-5D by gender, age groups, education levels, etc. The transformation from PROMIS-GHS to EQ-5D had a high accuracy of mean estimate on a group level, but not at the individual level.

7.
Spine (Phila Pa 1976) ; 44(13): E782-E787, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31205174

RESUMEN

STUDY DESIGN: A retrospective review of prospectively collected data. OBJECTIVE: The purpose of this study is to compare and validate several preoperative scores for predicting outcomes following spine tumor resection. SUMMARY OF BACKGROUND DATA: Preoperative risk assessment for patients undergoing spinal tumor resection remains challenging. At present, few risk assessment tools have been validated in this high-risk population. METHODS: The 2008 to 2014 National Surgical Quality Improvement database was used to identify all patients undergoing surgical resection of spinal tumors, stratified as extradural, intradural extramedullary, and intramedullary based on CPT codes. American Society of Anesthesiologists (ASA) score, modified Charlson Comorbidity Index (CCI), and modified Frailty Index (mFI) were computed. A binary logistic regression model was used to explore the relationship between these variables and postoperative outcomes, including mortality, major and minor adverse events, and hospital length of stay (LOS). Other significant variables such as demographics, operative time, and tumor location were controlled for in each model. RESULTS: Two thousand one hundred seventy patients met the inclusion criteria. Higher CCI scores were independent predictors of mortality (OR = 1.24, 95% CI: 1.14-1.36, P < 0.001), major adverse events (OR = 1.07, 95% CI: 1.01-1.31, P = 0.018), minor adverse events (OR = 1.15, 95% CI: 1.10-1.20, P < 0.001), and prolonged LOS (OR = 1.14, 95% CI: 1.09-1.19, P < 0.001). Patients' mFI scores were significantly associated with mortality and LOS, but not major or minor adverse events. ASA scores were not associated with any outcome metric when controlling for other variables. CONCLUSION: The CCI demonstrated superior predictive capacity compared with mFI and ASA scores and may be valuable as a preoperative risk assessment tool for patients undergoing surgical resection of spinal tumors. The validation of assessment scores is important for preoperative risk stratification and improving outcomes in this high-risk group. LEVEL OF EVIDENCE: 3.


Asunto(s)
Anestesiólogos/normas , Fragilidad/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Cuidados Preoperatorios/normas , Sociedades Médicas/normas , Neoplasias de la Columna Vertebral/diagnóstico , Adulto , Anciano , Femenino , Fragilidad/epidemiología , Fragilidad/cirugía , Humanos , Tiempo de Internación/tendencias , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/efectos adversos , Procedimientos Neuroquirúrgicos/normas , Complicaciones Posoperatorias/epidemiología , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Mejoramiento de la Calidad/normas , Estudios Retrospectivos , Medición de Riesgo/métodos , Medición de Riesgo/normas , Factores de Riesgo , Neoplasias de la Columna Vertebral/epidemiología , Neoplasias de la Columna Vertebral/cirugía
8.
J Neurosurg ; : 1-10, 2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31653806

RESUMEN

OBJECTIVE: Recent large-cohort sequencing studies have investigated the genomic landscape of meningiomas, identifying somatic coding alterations in NF2, SMARCB1, SMARCE1, TRAF7, KLF4, POLR2A, BAP1, and members of the PI3K and Hedgehog signaling pathways. Initial associations between clinical features and genomic subgroups have been described, including location, grade, and histology. However, further investigation using an expanded collection of samples is needed to confirm previous findings, as well as elucidate relationships not evident in smaller discovery cohorts. METHODS: Targeted sequencing of established meningioma driver genes was performed on a multiinstitution cohort of 3016 meningiomas for classification into mutually exclusive subgroups. Relevant clinical information was collected for all available cases and correlated with genomic subgroup. Nominal variables were analyzed using Fisher's exact tests, while ordinal and continuous variables were assessed using Kruskal-Wallis and 1-way ANOVA tests, respectively. Machine-learning approaches were used to predict genomic subgroup based on noninvasive clinical features. RESULTS: Genomic subgroups were strongly associated with tumor locations, including correlation of HH tumors with midline location, and non-NF2 tumors in anterior skull base regions. NF2 meningiomas were significantly enriched in male patients, while KLF4 and POLR2A mutations were associated with female sex. Among histologies, the results confirmed previously identified relationships, and observed enrichment of microcystic features among "mutation unknown" samples. Additionally, KLF4-mutant meningiomas were associated with larger peritumoral brain edema, while SMARCB1 cases exhibited elevated Ki-67 index. Machine-learning methods revealed that observable, noninvasive patient features were largely predictive of each tumor's underlying driver mutation. CONCLUSIONS: Using a rigorous and comprehensive approach, this study expands previously described correlations between genomic drivers and clinical features, enhancing our understanding of meningioma pathogenesis, and laying further groundwork for the use of targeted therapies. Importantly, the authors found that noninvasive patient variables exhibited a moderate predictive value of underlying genomic subgroup, which could improve with additional training data. With continued development, this framework may enable selection of appropriate precision medications without the need for invasive sampling procedures.

9.
J Neurosurg Pediatr ; 21(5): 449-455, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29473813

RESUMEN

OBJECTIVE Lumbar disc herniation (LDH) in the pediatric population is rare and exhibits unique characteristics compared with adult LDH. There are limited data regarding the safety and efficacy of minimally invasive surgery (MIS) using tubular retractors in pediatric patients with LDH. Here, the outcomes of MIS tubular microdiscectomy for the treatment of pediatric LDH are evaluated. METHODS Twelve consecutive pediatric patients with LDH were treated with MIS tubular microdiscectomy at the authors' institution between July 2011 and October 2015. Data were gathered from retrospective chart review and from mail or electronic questionnaires. The Macnab criteria and the Oswestry Disability Index (ODI) were used for outcome measurements. RESULTS The mean age at surgery was 17 ± 1.6 years (range 13-19 years). Seven patients were female (58%). Prior to surgical intervention, 100% of patients underwent conservative treatment, and 50% had epidural steroid injections. Preoperative low-back and leg pain, positive straight leg raise, and myotomal leg weakness were noted in 100%, 83%, and 67% of patients, respectively. The median duration of symptoms prior to surgery was 9 months (range 1-36 months). The LDH level was L5-S1 in 75% of patients and L4-5 in 25%. The mean ± SD operative time was 90 ± 21 minutes, the estimated blood loss was ≤ 25 ml in 92% of patients (maximum 50 ml), and no intraoperative or postoperative complications were noted at 30 days. The median hospital length of stay was 1 day (range 0-3 days). The median follow-up duration was 2.2 years (range 0-5.8 years). One patient experienced reherniation at 18 months after the initial operation and required a second same-level MIS tubular microdiscectomy to achieve resolution of symptoms. Of the 11 patients seen for follow-up, 10 patients (91%) reported excellent or good satisfaction according to the Macnab criteria at the last follow-up. Only 1 patient reported a fair level of satisfaction by using the same criteria. Seven patients completed an ODI evaluation at the last follow-up. For these 7 patients, the mean ODI low-back pain score was 19.7% (SEM 2.8%). CONCLUSIONS To the authors' knowledge, this is the longest outcomes study and the largest series of pediatric patients with LDH who were treated with MIS microdiscectomy using tubular retractors. These data suggest that MIS tubular microdiscectomy is safe and efficacious for pediatric LDH. Larger prospective cohort studies with longer follow-up are needed to better evaluate the long-term efficacy of MIS tubular microdiscectomy versus other open and MIS techniques for the treatment of pediatric LDH.


Asunto(s)
Discectomía/métodos , Desplazamiento del Disco Intervertebral/cirugía , Microcirugia/métodos , Adolescente , Discectomía/instrumentación , Femenino , Humanos , Vértebras Lumbares/cirugía , Imagen por Resonancia Magnética , Masculino , Microcirugia/instrumentación , Neuroendoscopía/instrumentación , Neuroendoscopía/métodos , Cuidados Preoperatorios/métodos , Estudios Retrospectivos , Instrumentos Quirúrgicos , Resultado del Tratamiento , Adulto Joven
10.
World Neurosurg ; 108: 112-117, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28807778

RESUMEN

The risk for spinal cord injuries (SCIs) ranging from devastating traumatic injuries, compression because of degenerative pathology, and neurapraxia is increased in patients with congenital spinal stenosis. Classical diagnostic criteria include an absolute anteroposterior diameter of <12-13 mm or a Torg-Pavlov ratio of <0.80-0.82; however, these factors do not take into account the size of the spinal cord, which varies across patients, independent of canal size. Recent large magnetic resonance imaging studies of population cohorts have allowed newer methods to emerge that account for both cord and canal size by measuring a spinal cord occupation ratio (SCOR). A SCOR defined as ≥70% on midsagittal imaging or ≥80% on axial imaging appears to be an effective method of identifying cord-canal mismatch, but requires further validation. Cord-canal size mismatch predisposes patients to SCI because of 1) less space within the canal lowering the amount of degenerative changes needed for cord compression, and 2) less cerebrospinal fluid surrounding the spinal cord decreasing the ability to absorb kinetic forces directed at the spine. Patients with cord-canal mismatch have been reported to be at a substantially higher risk of traumatic SCI, and present with degenerative cervical myelopathy at a younger age than patients without cord-canal mismatch. However, neurologic outcome after SCI has occurred does not appear to be different in patients with or without a cord-canal mismatch. Recognition that canal and cord size are both factors which predispose to SCI supports that cord-canal size mismatch rather than a narrow cervical canal in isolation should be viewed as the underlying mechanism predisposing to SCI.


Asunto(s)
Médula Cervical/diagnóstico por imagen , Traumatismos de la Médula Espinal/diagnóstico por imagen , Susceptibilidad a Enfermedades/diagnóstico por imagen , Humanos , Tamaño de los Órganos , Factores de Riesgo , Traumatismos de la Médula Espinal/epidemiología
11.
Front Neurol ; 8: 362, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28790973

RESUMEN

We present two recent cases of toddlers who developed malignant cerebellar edema subsequent to accidental ingestion of prescription opioids. Both children presented acute neurological decline, hydrocephalus, and tonsillar herniation requiring emergent ventricular drain placement, suboccipital craniectomy, and partial cerebellectomy. Together with several other reports, these cases suggest the existence of an uncommon yet severe syndrome of acute opioid-induced malignant cerebellar edema. We hypothesize that the condition results from a combination of primary opioid receptor-mediated changes in neuronal metabolism that are exacerbated by secondary hypoxic insult. If recognized promptly, this syndrome can be treated with emergent neurosurgical intervention with good clinical outcomes. These cases also illustrate the unintended consequences and innocent victims of the spiraling prescription opioid epidemic, which will likely increase in prevalence. Recognition of this syndrome by clinicians is thus critical.

12.
Nat Med ; 23(8): 997-1003, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28692063

RESUMEN

The choroid plexus epithelium (CPE) secretes higher volumes of fluid (cerebrospinal fluid, CSF) than any other epithelium and simultaneously functions as the blood-CSF barrier to gate immune cell entry into the central nervous system. Posthemorrhagic hydrocephalus (PHH), an expansion of the cerebral ventricles due to CSF accumulation following intraventricular hemorrhage (IVH), is a common disease usually treated by suboptimal CSF shunting techniques. PHH is classically attributed to primary impairments in CSF reabsorption, but little experimental evidence supports this concept. In contrast, the potential contribution of CSF secretion to PHH has received little attention. In a rat model of PHH, we demonstrate that IVH causes a Toll-like receptor 4 (TLR4)- and NF-κB-dependent inflammatory response in the CPE that is associated with a ∼3-fold increase in bumetanide-sensitive CSF secretion. IVH-induced hypersecretion of CSF is mediated by TLR4-dependent activation of the Ste20-type stress kinase SPAK, which binds, phosphorylates, and stimulates the NKCC1 co-transporter at the CPE apical membrane. Genetic depletion of TLR4 or SPAK normalizes hyperactive CSF secretion rates and reduces PHH symptoms, as does treatment with drugs that antagonize TLR4-NF-κB signaling or the SPAK-NKCC1 co-transporter complex. These data uncover a previously unrecognized contribution of CSF hypersecretion to the pathogenesis of PHH, demonstrate a new role for TLRs in regulation of the internal brain milieu, and identify a kinase-regulated mechanism of CSF secretion that could be targeted by repurposed US Food and Drug Administration (FDA)-approved drugs to treat hydrocephalus.


Asunto(s)
Hemorragia Cerebral/inmunología , Líquido Cefalorraquídeo/metabolismo , Plexo Coroideo/metabolismo , Hidrocefalia/inmunología , FN-kappa B/inmunología , Receptor Toll-Like 4/inmunología , Acetazolamida/farmacología , Animales , Antioxidantes/farmacología , Western Blotting , Bumetanida/farmacología , Hemorragia Cerebral/complicaciones , Ventrículos Cerebrales , Plexo Coroideo/efectos de los fármacos , Plexo Coroideo/inmunología , Diuréticos/farmacología , Técnicas de Silenciamiento del Gen , Técnicas de Inactivación de Genes , Hidrocefalia/etiología , Hidrocefalia/metabolismo , Immunoblotting , Inmunohistoquímica , Inmunoprecipitación , Inflamación , Prolina/análogos & derivados , Prolina/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas , Ratas Wistar , Salicilanilidas/farmacología , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Sulfonamidas/farmacología , Tiocarbamatos/farmacología , Receptor Toll-Like 4/genética
13.
Diagnóstico (Perú) ; 24(1/2): 5-9, jul.-ago. 1989. tab
Artículo en Español | LILACS, LIPECS | ID: lil-83009

RESUMEN

La Hepatitis viral es un problema mundial de salud pública. Se presenta un estudio realizado en 164 individuos habitantes de la localidad de Ampama, área geográfica perteneciente a la región amazónica peruana. En este grupo poblacional se determinaron marcadores serológicos de virus A,B y Delta, los que incluyeron Anti-HA, Anti-HA-igM, HBsAg, HBeAg, Anti-HBc, Anti-HBc-igM y Anti-d. El presente trabajo se planificó teniendo como objetivo determinar la incidencia de infecciones debidas al virus A, virus B y el Agente Delta en dicha área de la amazonía peruana, y como consecuencia, presentar sugerencias para su control epidemiológico. Se encontró una incidencia muy alta de positividad para uno o más de los marcadores serológicos del virus B, con resultados aún superiores al de otras áreas del tercer mundo. Anti-HA fue detectado en prácticamente todos los individuos de la población evaluada en este estudio. En lo referente al Agente Delta, las determinaciones del Anti-d mostró la existencia de este virus con una incidencia similar a otras áreas del orbe donde es endémico. presentamos conclusiones y recomendaciones, con énfasis especial en la implementación de medidas especiales de prevención


Asunto(s)
Humanos , Masculino , Femenino , Hepatitis D/epidemiología , Hepatitis C/epidemiología , Hepatitis A/epidemiología , Hepatitis B/epidemiología , Hepatitis Viral Humana/epidemiología , Anticuerpos contra la Hepatitis B
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