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1.
Acta Neuropathol ; 144(4): 747-765, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35945463

RESUMEN

Gliomas arising in the setting of neurofibromatosis type 1 (NF1) are heterogeneous, occurring from childhood through adulthood, can be histologically low-grade or high-grade, and follow an indolent or aggressive clinical course. Comprehensive profiling of genetic alterations beyond NF1 inactivation and epigenetic classification of these tumors remain limited. Through next-generation sequencing, copy number analysis, and DNA methylation profiling of gliomas from 47 NF1 patients, we identified 2 molecular subgroups of NF1-associated gliomas. The first harbored biallelic NF1 inactivation only, occurred primarily during childhood, followed a more indolent clinical course, and had a unique epigenetic signature for which we propose the terminology "pilocytic astrocytoma, arising in the setting of NF1". The second subgroup harbored additional oncogenic alterations including CDKN2A homozygous deletion and ATRX mutation, occurred primarily during adulthood, followed a more aggressive clinical course, and was epigenetically diverse, with most tumors aligning with either high-grade astrocytoma with piloid features or various subclasses of IDH-wildtype glioblastoma. Several patients were treated with small molecule MEK inhibitors that resulted in stable disease or tumor regression when used as a single agent, but only in the context of those tumors with NF1 inactivation lacking additional oncogenic alterations. Together, these findings highlight recurrently altered pathways in NF1-associated gliomas and help inform targeted therapeutic strategies for this patient population.


Asunto(s)
Astrocitoma , Neoplasias Encefálicas , Glioma , Neurofibromatosis 1 , Adulto , Astrocitoma/genética , Neoplasias Encefálicas/genética , Glioma/genética , Glioma/patología , Homocigoto , Humanos , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/genética , Eliminación de Secuencia
2.
BMC Public Health ; 21(1): 1690, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34530789

RESUMEN

BACKGROUND: Malnutrition was the main cause of death among children below 5 years in every state of India in 2017. Despite several flagship programmes and schemes implemented by the Government of India, the latest edition of the Global Nutrition Report 2018 addressed that India tops in the number of stunted children, which is a matter of concern. Thus, a micro-level study was designed to know the level of nutritional status and to study this by various disaggregate levels, as well as to examine the risk factors of stunting among pre-school children aged 36-59 months in Malda. METHOD: A primary cross-sectional quantitative survey was conducted using structured questionnaires following a multi-stage, stratified simple random sampling procedure in 2018. A sum of 731 mothers with at least one eligible child aged 36-59 months were the study participants. Anthropometric measures of children were collected following the WHO child growth standard. Children were classified as stunted, wasted, and underweight if their HAZ, WHZ, and WAZ scores, respectively, were less than -2SD. The random intercept multilevel logistic regression model has been employed to estimate the effects of possible risk factors on childhood stunting. RESULTS: The prevalence of stunting in the study area is 40% among children aged 36-59 months, which is a very high prevalence as per the WHO's cut-off values (≥40%) for public health significance. Results of the multilevel analysis revealed that preceding birth interval, low birth weight, duration of breastfeeding, mother's age at birth, mother's education, and occupation are the associated risk factors of stunting. Among them, low birth weight (OR 2.22, 95% CI: 1.44-3.41) and bidi worker as mothers' occupation (OR 1.92, 95% CI: 1.18-3.12) are the most influencing factors of stunting. Further, about 14 and 86% variation in stunting lie at community and child/household level, respectively. CONCLUSION: Special attention needs to be placed on the modifiable risk factors of childhood stunting. Policy interventions should direct community health workers to encourage women as well as their male partners to increase birth interval using various family planning practices, provide extra care for low birth weight baby, that can help to reduce childhood stunting.


Asunto(s)
Desnutrición , Estado Nutricional , Niño , Preescolar , Estudios Transversales , Femenino , Trastornos del Crecimiento/epidemiología , Humanos , India/epidemiología , Lactante , Masculino , Prevalencia , Factores de Riesgo
3.
Ophthalmology ; 127(6): 804-813, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32139107

RESUMEN

PURPOSE: To determine the usefulness of a comprehensive, targeted-capture next-generation sequencing (NGS) assay for the clinical management of children undergoing enucleation for retinoblastoma. DESIGN: Cohort study. PARTICIPANTS: Thirty-two children with retinoblastoma. METHODS: We performed targeted NGS using the UCSF500 Cancer Panel (University of California, San Francisco, San Francisco, CA) on formalin-fixed, paraffin-embedded tumor tissue along with constitutional DNA isolated from peripheral blood, buccal swab, or uninvolved optic nerve. Peripheral blood samples were also sent to a commercial laboratory for germline RB1 mutation testing. MAIN OUTCOME MEASURES: Presence or absence of germline RB1 mutation or deletion, tumor genetic profile, and association of genetic alterations with clinicopathologic features. RESULTS: Germline mutation or deletion of the RB1 gene was identified in all children with bilateral retinoblastoma (n = 12), and these NGS results were 100% concordant with commercial germline RB1 mutation analysis. In tumor tissue tested with NGS, biallelic inactivation of RB1 was identified in 28 tumors and focal MYCN amplification was identified in 4 tumors (2 with wild-type RB1 and 2 with biallelic RB1 inactivation). Additional likely pathogenic alterations beyond RB1 were identified in 13 tumors (41%), several of which have not been reported previously in retinoblastoma. These included focal amplifications of MDM4 and RAF1, as well as damaging mutations involving BCOR, ARID1A, MGA, FAT1, and ATRX. The presence of additional likely pathogenetic mutations beyond RB1 inactivation was associated with aggressive histopathologic features, including higher histologic grade and anaplasia, and also with both unilateral and sporadic disease. CONCLUSIONS: Comprehensive NGS analysis reliably detects relevant mutations, amplifications, and chromosomal copy number changes in retinoblastoma. The presence of genetic alterations beyond RB1 inactivation correlates with aggressive histopathologic features.


Asunto(s)
Silenciador del Gen , Mutación de Línea Germinal , Neoplasias de la Retina/genética , Neoplasias de la Retina/patología , Proteínas de Unión a Retinoblastoma/genética , Retinoblastoma/genética , Retinoblastoma/patología , Ubiquitina-Proteína Ligasas/genética , Niño , Preescolar , Estudios de Cohortes , Análisis Mutacional de ADN , ADN de Neoplasias/genética , Enucleación del Ojo , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Adhesión en Parafina , Neoplasias de la Retina/cirugía , Retinoblastoma/cirugía , Fijación del Tejido
4.
Lancet Oncol ; 20(7): 1011-1022, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31151904

RESUMEN

BACKGROUND: Paediatric low-grade glioma is the most common CNS tumour of childhood. Although overall survival is good, disease often recurs. No single universally accepted treatment exists for these patients; however, standard cytotoxic chemotherapies are generally used. We aimed to assess the activity of selumetinib, a MEK1/2 inhibitor, in these patients. METHODS: The Pediatric Brain Tumor Consortium performed a multicentre, phase 2 study in patients with paediatric low-grade glioma in 11 hospitals in the USA. Patients aged 3-21 years with a Lansky or Karnofsky performance score greater than 60 and the presence of recurrent, refractory, or progressive paediatric low-grade glioma after at least one standard therapy were eligible for inclusion. Patients were assigned to six unique strata according to histology, tumour location, NF1 status, and BRAF aberration status; herein, we report the results of strata 1 and 3. Stratum 1 comprised patients with WHO grade I pilocytic astrocytoma harbouring either one of the two most common BRAF aberrations (KIAA1549-BRAF fusion or the BRAFV600E [Val600Glu] mutation). Stratum 3 comprised patients with any neurofibromatosis type 1 (NF1)-associated paediatric low-grade glioma (WHO grades I and II). Selumetinib was provided as capsules given orally at the recommended phase 2 dose of 25 mg/m2 twice daily in 28-day courses for up to 26 courses. The primary endpoint was the proportion of patients with a stratum-specific objective response (partial response or complete response), as assessed by the local site and sustained for at least 8 weeks. All responses were reviewed centrally. All eligible patients who initiated treatment were evaluable for the activity and toxicity analyses. Although the trial is ongoing in other strata, enrolment and planned follow-up is complete for strata 1 and 3. This trial is registered with ClinicalTrials.gov, number NCT01089101. FINDINGS: Between July 25, 2013, and June 12, 2015, 25 eligible and evaluable patients were accrued to stratum 1, and between Aug 28, 2013, and June 25, 2015, 25 eligible and evaluable patients were accrued to stratum 3. In stratum 1, nine (36% [95% CI 18-57]) of 25 patients achieved a sustained partial response. The median follow-up for the 11 patients who had not had a progression event by Aug 9, 2018, was 36·40 months (IQR 21·72-45·59). In stratum 3, ten (40% [21-61]) of 25 patients achieved a sustained partial response; median follow-up was 48·60 months (IQR 39·14-51·31) for the 17 patients without a progression event by Aug 9, 2018. The most frequent grade 3 or worse adverse events were elevated creatine phosphokinase (five [10%]) and maculopapular rash (five [10%]). No treatment-realted deaths were reported. INTERPRETATION: Selumetinib is active in recurrent, refractory, or progressive pilocytic astrocytoma harbouring common BRAF aberrations and NF1-associated paediatric low-grade glioma. These results show that selumetinib could be an alternative to standard chemotherapy for these subgroups of patients, and have directly led to the development of two Children's Oncology Group phase 3 studies comparing standard chemotherapy to selumetinib in patients with newly diagnosed paediatric low-grade glioma both with and without NF1. FUNDING: National Cancer Institute Cancer Therapy Evaluation Program, the American Lebanese Syrian Associated Charities, and AstraZeneca.


Asunto(s)
Bencimidazoles/uso terapéutico , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Glioma/tratamiento farmacológico , Adolescente , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/patología , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Glioma/genética , Glioma/patología , Humanos , Masculino , Clasificación del Tumor , Neoplasias Primarias Múltiples/patología , Neurofibromatosis 1/patología , Proteínas Proto-Oncogénicas B-raf/genética , Adulto Joven
5.
Acta Neuropathol ; 137(1): 139-150, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30196423

RESUMEN

Radiotherapy improves survival for common childhood cancers such as medulloblastoma, leukemia, and germ cell tumors. Unfortunately, long-term survivors suffer sequelae that can include secondary neoplasia. Gliomas are common secondary neoplasms after cranial or craniospinal radiation, most often manifesting as high-grade astrocytomas with poor clinical outcomes. Here, we performed genetic profiling on a cohort of 12 gliomas arising after therapeutic radiation to determine their molecular pathogenesis and assess for differences in genomic signature compared to their spontaneous counterparts. We identified a high frequency of TP53 mutations, CDK4 amplification or CDKN2A homozygous deletion, and amplifications or rearrangements involving receptor tyrosine kinase and Ras-Raf-MAP kinase pathway genes including PDGFRA, MET, BRAF, and RRAS2. Notably, all tumors lacked alterations in IDH1, IDH2, H3F3A, HIST1H3B, HIST1H3C, TERT (including promoter region), and PTEN, which genetically define the major subtypes of diffuse gliomas in children and adults. All gliomas in this cohort had very low somatic mutation burden (less than three somatic single nucleotide variants or small indels per Mb). The ten high-grade gliomas demonstrated markedly aneuploid genomes, with significantly increased quantity of intrachromosomal copy number breakpoints and focal amplifications/homozygous deletions compared to spontaneous high-grade gliomas, likely as a result of DNA double-strand breaks induced by gamma radiation. Together, these findings demonstrate a distinct molecular pathogenesis of secondary gliomas arising after radiation therapy and identify a genomic signature that may aid in differentiating these tumors from their spontaneous counterparts.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Glioma/genética , Glioma/radioterapia , Adolescente , Adulto , Astrocitoma/radioterapia , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/radioterapia , Niño , Preescolar , Femenino , Genómica , Homocigoto , Humanos , Masculino , Mutación/genética , Eliminación de Secuencia/genética , Telomerasa/genética , Adulto Joven
6.
J Neurooncol ; 140(3): 629-638, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30206764

RESUMEN

BACKGROUND: Diffuse intrinsic pontine glioma (DIPG) is a rare, aggressive brain tumor with no known cure. Reirradiation (reRT) at recurrence can prolong survival. The impact of irradiation may be heightened when combined with PD-1 inhibition. We describe our experience using reRT, with or without PD-1 inhibition, in a cohort of patients with recurrent DIPG. METHODS: We performed a retrospective cohort analysis of children who received reRT with or without concomitant PD-1 inhibition for recurrent DIPG at a single institution between 2005 and 2016. We compared progression-free (PFS) and overall survival (OS) between those who received reRT alone or in combination with PD-1 inhibition. We then compared reRT to a cohort of patients who did not receive reRT. RESULTS: Thirty-one patients were included (8-reRT with nivolumab; 4-reRT alone; 19-no reRT). Patients who received reRT had prolonged OS compared to no reRT (22.9 months-reRT with nivolumab; 20.4 months-reRT alone; 8.3 months-no reRT; p < 0.0001). Patients who received reRT with nivolumab vs. reRT only had slightly prolonged OS from diagnosis and from reRT (22.9 vs. 20.4 months for time from diagnosis; 6.8 vs. 6.0 months for time from reRT). All patients receiving reRT with or without nivolumab tolerated the therapy without acute or late toxicity. CONCLUSIONS: Our experience demonstrates the tolerability of reRT with concurrent PD-1 inhibition for recurrent DIPG and suggests that combination therapy may offer survival benefit. Future prospective studies are needed to confirm the benefits of this combination therapy.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Neoplasias del Tronco Encefálico/tratamiento farmacológico , Neoplasias del Tronco Encefálico/radioterapia , Glioma/tratamiento farmacológico , Glioma/radioterapia , Nivolumab/uso terapéutico , Adolescente , Niño , Preescolar , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Supervivencia sin Progresión , Reirradiación , Estudios Retrospectivos
8.
Phys Rev E ; 109(2-1): 024411, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38491641

RESUMEN

The hysteretic behavior exhibited by collagen fibrils, when subjected to cyclic loading, is known to result in both dissipation as well as accumulation of residual strain. On subsequent relaxation, partial recovery has also been reported. Cross-links have been considered to play a key role in overall mechanical properties. Here, we modify an existing coarse-grained molecular dynamics model for collagen fibril with initially cross-linked collagen molecules, which is known to reproduce the response to uniaxial strain, by incorporating reformation of cross-links to allow for possible recovery of the fibril. Using molecular dynamics simulations, we show that our model successfully replicates the key features observed in experimental data, including the movement of hysteresis loops, the time evolution of residual strains and energy dissipation, as well as the recovery observed during relaxation. We also show that the characteristic cycle number, describing the approach toward steady state, has a value similar to that in experiments. We also emphasize the vital role of the degree of cross-linking on the key features of the macroscopic response to cyclic loading.


Asunto(s)
Colágeno , Simulación de Dinámica Molecular , Fenómenos Biomecánicos , Matriz Extracelular , Estrés Mecánico
10.
PLoS One ; 18(8): e0289701, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37556482

RESUMEN

BACKGROUND: The adoption of maternity services and postpartum modern contraception are the two most crucial components that help in reducing maternal and infant mortality; still, India is consistently struggling with it. This paper, therefore, aimed to examine the linkages between use of maternity services and postpartum modern contraceptive adoption. DATA AND METHODS: The required reproductive calendar data were extracted from the 2015-16 and 2019-21 National Family Health Survey (NFHS) datasets. The assessment was made based on a sample of currently married women aged 15-24 years who had given most recent childbirth in five years preceding the survey. For the analysis, a time-to-event approach was applied using the Kaplan-Meier survival statistic, Log-Rank Chi-square test and Cox-Proportional Hazard (Cox-PH) models. RESULTS: The results revealed that the proportion of postpartum modern contraceptive uptake among young users increased by 9%, from 33% in 2015-16 to 42% in 2019-21. The Cox-PH models revealed that, in both NFHS waves, the associations between various components of maternity services and postpartum modern contraceptive uptake were strongly significant, even after controlling for selected socio-economic and demographic correlates. CONCLUSIONS: The findings of this study reinforced urgent need for implementing integrated maternal-child health and family planning programmes and for boosting effective family planning counselling by health professionals to promote and motivate young women with a desire to early adoption of modern contraception in subsequent months after a recent childbirth.


Asunto(s)
Anticoncepción , Anticonceptivos , Humanos , Femenino , Embarazo , Servicios de Planificación Familiar , Periodo Posparto , Conducta Anticonceptiva , Parto , India , Encuestas Epidemiológicas
11.
Phys Rev E ; 107(5-2): 055002, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37329015

RESUMEN

In a two-phase solid, we examine the growth of a preexisting macroscopic crack based on simulations of a random spring network model. We find that the enhancement in toughness, as well as strength, is strongly dependent on the ratio of elastic moduli as well as on the relative proportion of the phases. We find that the mechanism that leads to enhancement in toughness is not the same as that for enhancement in strength; however, the overall enhancement is similar in mode I and mixed-mode loading. Based on the crack paths, and the spread of the fracture process zone, we identify the type of fracture to transition from nucleation type, for close to single-phase compositions, whether hard or soft, to avalanche type for more mixed compositions. We also show that the associated avalanche distributions exhibit power-law statistics with different exponents for each phase. The significance of variations in the avalanche exponents with the relative proportion of phases and possible connections to the fracture types are discussed in detail.


Asunto(s)
Estrés Mecánico , Módulo de Elasticidad
12.
J Neurooncol ; 106(2): 367-75, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21826561

RESUMEN

Management of pediatric intracranial ependymomas poses a major challenge, and optimal treatment remains controversial. We sought to investigate the roles of surgery, radiation, and chemotherapy in a historical cohort. Thirty-nine children, age 21 or younger, with non-metastatic intracranial ependymomas were treated from 1972 to 2008. Median age was 8 years (range 0.2-19.1). Twenty-one patients (54%) underwent GTRs, and 18 (45%) underwent STRs. Twenty-six patients (67%) received upfront adjuvant RT (67%), and 14 (44%) received adjuvant chemotherapy. Twenty-four patients had disease recurrence and 12 died. Only one patient recurred after 5 years. Median PFS was 2.7 years and median OS was 20 years. Fifteen year PFS and OS were 30 and 67%. Adjuvant RT was associated with improved PFS (P = 0.045), and remained significant after adjusting for EOR (P = 0.04). Greater EOR trended towards prolonged survival, but did not reach statistical significance (P = 0.156). Of the patients that underwent GTR, the median PFS was 38 months for those treated with adjuvant RT versus 30 months for those that were not treated with RT. Of the patients that had STR, the median PFS for those treated with RT was 26.3 months versus 6.9 months for those were not treated with RT. In conclusion, for localized intracranial pediatric ependymomas, adjuvant RT is associated with improved PFS, even after adjusting for EOR. Our findings suggest the benefit of RT even in the presence of GTR. Future prospective studies with larger sample number are needed to validate our findings.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/terapia , Ependimoma/mortalidad , Ependimoma/terapia , Adolescente , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/patología , Quimioradioterapia Adyuvante , Niño , Preescolar , Terapia Combinada , Supervivencia sin Enfermedad , Ependimoma/patología , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Clasificación del Tumor , Procedimientos Neuroquirúrgicos , Pronóstico , Modelos de Riesgos Proporcionales , Radioterapia , Adulto Joven
13.
Phys Rev E ; 106(4-1): 044407, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36397482

RESUMEN

Collagen fibrils, when subjected to cyclic loading, are known to exhibit hysteretic behavior with energy dissipation that is partially recovered on relaxation. In this paper, we develop a kinetic model for a collagen fibril incorporating presence of hidden loops and stochastic fragmentation as well as reformation of sacrificial bonds. We show that the model reproduces well the characteristic features of reported experimental data on cyclic response of collagen fibrils, such as moving hysteresis loops, time evolution of residual strains and energy dissipation, recovery on relaxation, etc. We show that the approach to the steady state is controlled by a characteristic cycle number for both residual strain as well as energy dissipation and is in good agreement with reported existing experimental data.

14.
J Clin Oncol ; 40(33): 3839-3847, 2022 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-35820112

RESUMEN

PURPOSE: Metastatic retinoblastoma has a poor prognosis when treated with conventional chemotherapy and radiation therapy (RT). Intensified therapy may improve the outcome. METHODS: A prospective, international trial enrolled patients with extraocular retinoblastoma. Patients with stage II or III (locoregional) retinoblastoma received four cycles of chemotherapy, followed by involved field RT (45 Gy). Patients with stage IVa or IVb (metastatic or trilateral) retinoblastoma also received four cycles of chemotherapy and those with ≥ partial response then received one cycle of high-dose carboplatin, thiotepa, and etoposide with autologous hematopoietic stem-cell support. Patients with stage IVa or IVb with residual tumor postchemotherapy received RT. The proportion of patients who achieved event-free survival would be reported and compared with historical controls separately for each of the three groups of patients. RESULTS: Fifty-seven eligible patients were included in the analyses. Event-free survival at 1 year was 88.1% (90% CI, 66.6 to 96.2) for stage II-III, 82.6% (90% CI, 61.0 to 92.9) for stage IVa, and 28.3% (90% CI, 12.7 to 46.2) for stage IVb/trilateral. Toxicity was significant as expected and included two therapy-related deaths. CONCLUSION: Intensive multimodality therapy is highly effective for patients with regional extraocular retinoblastoma and stage IVa metastatic retinoblastoma. Although the study met its aim for stage IVb, more effective therapy is still required for patients with CNS involvement (ClinicalTrials.gov identifier: NCT00554788).


Asunto(s)
Neoplasias de la Retina , Retinoblastoma , Niño , Humanos , Terapia Combinada/efectos adversos , Estudios Prospectivos , Neoplasias de la Retina/terapia , Neoplasias de la Retina/patología , Retinoblastoma/terapia , Retinoblastoma/patología
15.
Am J Med Genet C Semin Med Genet ; 157C(2): 136-46, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21495172

RESUMEN

The RASopathies, one of the largest groups of multiple congenital anomaly syndromes known, are caused by germline mutations in various genes encoding components of the Ras/mitogen-activated protein kinase (MAPK) pathway. The RASopathies have many overlapping characteristics, including craniofacial manifestations, cardiac malformations, cutaneous, musculoskeletal, gastrointestinal, and ocular abnormalities, neurocognitive impairment, hypotonia, and an increased risk of developing cancer. Costello syndrome (CS) and cardio-facio-cutaneous (CFC) syndrome are two of the more rare RASopathies. CS is caused by activating mutations in HRAS, and CFC is caused by dysregulation of signaling in the Ras/MAPK pathway due to mutations in BRAF, MEK1, or MEK2. The Ras/MAPK pathway, which has been well-studied in cancer, is an attractive target for inhibition in the treatment of various malignancies utilizing small molecule therapeutics that specifically inhibit the pathway. With many inhibitors of the Ras/MAPK pathway in clinical trials, the notion of using these molecules to ameliorate developmental defects in CS and CFC is under consideration. CS and CFC, like other syndromes in their class, have a progressive phenotype and may be amenable to inhibition or normalization of signaling.


Asunto(s)
Ensayos Clínicos como Asunto/métodos , Síndrome de Costello/genética , Neurofibromatosis 1/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proyectos de Investigación , Transducción de Señal/genética , Síndrome de Costello/tratamiento farmacológico , Displasia Ectodérmica/tratamiento farmacológico , Displasia Ectodérmica/genética , Facies , Insuficiencia de Crecimiento/tratamiento farmacológico , Insuficiencia de Crecimiento/genética , Farnesiltransferasa/antagonistas & inhibidores , Cardiopatías Congénitas/tratamiento farmacológico , Cardiopatías Congénitas/genética , Humanos , MAP Quinasa Quinasa 1/antagonistas & inhibidores , Asociación entre el Sector Público-Privado , Quinasas raf/antagonistas & inhibidores
16.
J Neurooncol ; 98(1): 117-23, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19936623

RESUMEN

Atypical Teratoid/Rhabdoid tumors (AT/RT) of the central nervous system are rare but aggressive tumors of childhood. Median survival with surgery and standard chemotherapy is less than 12 months. In an attempt to improve outcome, patients were treated with aggressive surgical resection and multi-agent chemotherapy, followed by high dose chemotherapy with autologous stem cell rescue. Nine consecutive children (median age 21 months) were diagnosed with AT/RT at the University of California San Francisco Childrens Hospital from 1997 to 2007 and treated with this aggressive approach. Diagnosis was confirmed using molecular markers. There are two long-term survivors (78 and 98 months from diagnosis). One additional patient is alive with disease. Three patients died of disease during therapy. Three patients died of disease after therapy was complete. There were no toxic deaths. Two of nine patients treated for AT/RT at our institution with high dose chemotherapy and autologous bone marrow transplant are long-term survivors, suggesting that a subset of patients can be cured with this approach.


Asunto(s)
Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/cirugía , Quimioterapia Adyuvante/métodos , Tumor Rabdoide/tratamiento farmacológico , Tumor Rabdoide/cirugía , Trasplante de Células Madre/métodos , Preescolar , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Estudios Retrospectivos , Sobrevivientes , Trasplante Autólogo/métodos
17.
J Neurooncol ; 96(2): 151-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19585223

RESUMEN

Despite the use of radiation and chemotherapy, the prognosis for children with diffuse brainstem gliomas is extremely poor. There is a need for relevant brainstem tumor models that can be used to test new therapeutic agents and delivery systems in pre-clinical studies. We report the development of a brainstem-tumor model in rats and the application of bioluminescence imaging (BLI) for monitoring tumor growth and response to therapy as part of this model. Luciferase-modified human glioblastoma cells from five different tumor cell sources (either cell lines or serially-passaged xenografts) were implanted into the pontine tegmentum of athymic rats using an implantable guide-screw system. Tumor growth was monitored by BLI and tumor volume was calculated by three-dimensional measurements from serial histopathologic sections. To evaluate if this model would allow detection of therapeutic response, rats bearing brainstem U-87 MG or GS2 glioblastoma xenografts were treated with the DNA methylating agent temozolomide (TMZ). For each of the tumor cell sources tested, BLI monitoring revealed progressive tumor growth in all animals, and symptoms caused by tumor burden were evident 26-29 days after implantation of U-87 MG, U-251 MG, GBM6, and GBM14 cells, and 37-47 days after implantation of GS2 cells. Histopathologic analysis revealed tumor growth within the pons in all rats and BLI correlated quantitatively with tumor volume. Variable infiltration was evident among the different tumors, with GS2 tumor cells exhibiting the greatest degree of infiltration. TMZ treatment groups were included for experiments involving U-87 MG and GS2 cells, and in each case TMZ delayed tumor growth, as indicated by BLI monitoring, and significantly extended survival of animal subjects. Our results demonstrate the development of a brainstem tumor model in athymic rats, in which tumor growth and response to therapy can be accurately monitored by BLI. This model is well suited for pre-clinical testing of therapeutics that are being considered for treatment of patients with brainstem tumors.


Asunto(s)
Neoplasias del Tronco Encefálico/diagnóstico , Glioma/diagnóstico , Luciferasas , Sustancias Luminiscentes , Animales , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias del Tronco Encefálico/tratamiento farmacológico , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Diagnóstico por Imagen , Modelos Animales de Enfermedad , Glioma/tratamiento farmacológico , Humanos , Etiquetado Corte-Fin in Situ/métodos , Estimación de Kaplan-Meier , Masculino , Trasplante de Neoplasias/métodos , Ratas , Ratas Desnudas , Temozolomida , Factores de Tiempo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
18.
J Neurooncol ; 100(1): 121-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20221671

RESUMEN

To report long-term results for children with low-grade hypothalamic/chiasmatic gliomas treated on a phase II chemotherapy protocol. Between 1984 and 1992, 33 children with hypothalamic/chiasmatic LGGs received TPDCV chemotherapy on a phase II prospective trial. Median age was 3.0 years (range 0.3-16.2). Twelve patients (36%) underwent STRs, 14 (42%) biopsy only, and seven (21%) no surgery. Twenty patients (61%) had pathologic JPAs, nine (27%) grade II gliomas, and four (12%) no surgical sampling. Median f/u for surviving patients was 15.2 years (range 5.3-20.7); 20 of the 23 surviving patients had 14 or more years of follow-up. Fifteen-year PFS and OS were 23.4 and 71.2%, respectively. Twenty-five patients progressed, of whom 13 are NED, two are AWD, and 10 have died. All children who died were diagnosed and first treated at age three or younger. Age at diagnosis was significantly associated with relapse and survival (P = 0.004 for PFS and P = 0.037 for OS). No PFS or OS benefit was seen with STR versus biopsy/no sampling (P = 0.58 for PFS, P = 0.59 for OS). For patients with JPAs and WHO grade II tumors, the 15-year PFS was 18.8 and 22.2% (P = 0.95) and 15-year OS was 73.7 and 55.6% (P = 0.17), respectively. Upfront TPDCV for children with hypothalamic/chiasmatic LGGs resulted in 15-year OS of 71.2% and 15-year PFS of 23.4%. No survival benefit is demonstrated for greater extent of resection. Age is a significant prognostic factor for progression and survival.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Glioma/tratamiento farmacológico , Neoplasias Hipotalámicas/tratamiento farmacológico , Adolescente , Factores de Edad , Niño , Preescolar , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Glioma/mortalidad , Humanos , Neoplasias Hipotalámicas/mortalidad , Lactante , Lomustina/uso terapéutico , Estudios Longitudinales , Masculino , Mitolactol/uso terapéutico , Valor Predictivo de las Pruebas , Procarbazina/uso terapéutico , Estudios Retrospectivos , Terapia Recuperativa/métodos , Tioguanina/uso terapéutico , Resultado del Tratamiento , Vincristina/uso terapéutico
19.
PLoS One ; 15(12): e0243553, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33296428

RESUMEN

OBJECTIVE: The present study aims to examine the association between women's decision-making autonomy and utilization of maternal healthcare services among the currently married women in India. METHODS: A total of 32,698 currently married women aged 15-49 years who had at least one live birth in the past five years preceding the survey and had information regarding autonomy collected by the National Family Health Survey 2015-16 were used for analysis. Bivariate and multivariate logistic regression models were employed for the analyses of this study. RESULTS: Utilization of maternal healthcare services was higher among the women having a high level of decision-making autonomy compared to those who had a low autonomy in the household. The regression results indicate that women's autonomy was significantly associated with increased odds of maternal healthcare services in India. Women with high autonomy had 37% and 33% greater likelihood of receiving ANC (AOR: 1.37, 95% CI: 1.25-1.50) and PNC care (AOR: 1.33, 95% CI: 1.24-1.42) respectively compared to women having low autonomy. However, no significant association was observed between women's autonomy and institutional delivery in the adjusted analysis. CONCLUSION: This study recommends the need for comprehensive strategies involving improvement of women's autonomy along with expansion of education, awareness generation regarding the importance of maternity care, and enhancing public health infrastructure to ensure higher utilization of maternal healthcare services that would eventually reduce maternal mortality.


Asunto(s)
Servicios de Salud Materna/tendencias , Aceptación de la Atención de Salud/psicología , Autonomía Personal , Adolescente , Adulto , Toma de Decisiones , Parto Obstétrico/estadística & datos numéricos , Escolaridad , Femenino , Conocimientos, Actitudes y Práctica en Salud/etnología , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , India/epidemiología , Salud Materna/estadística & datos numéricos , Salud Materna/tendencias , Servicios de Salud Materna/estadística & datos numéricos , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Embarazo , Atención Prenatal/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
20.
Phys Rev E ; 102(5-1): 053002, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33327211

RESUMEN

Multiphase materials, such as composite materials, exhibit multiple competing failure mechanisms during the growth of a macroscopic defect. For the simulation of the overall fracture process in such materials, we develop a two-phase spring network model that accounts for the architecture between the different components as well as the respective disorders in their failure characteristics. In the specific case of a plain weave architecture, we show that any offset between the layers reduces the delocalization of the stresses at the crack tip and thereby substantially lowers the strength and fracture toughness of the overall laminate. The avalanche statistics of the broken springs do not show a distinguishable dependence on the offsets between layers. The power-law exponents are found to be much smaller than that of disordered spring network models in the absence of a crack. A discussion is developed on the possibility of the avalanche statistics being those near breakdown.

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