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2.
Womens Health Rep (New Rochelle) ; 4(1): 103-110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874238

RESUMO

Background: Orthopedic residency programs increasingly use websites and social media to reach students. This accelerated during the COVID-19 pandemic, especially as away rotations became limited. Women remain a minority of orthopedic residents, and there are no data that indicate the correlation between department/program website content or social media presence on the gender diversity of residency classes. Methods: Orthopedic department websites were assessed between June 2021 and January 2022 to identify program director's gender, as well as the gender composition of the faculty and residents. Instagram presence for the department and/or program was also identified. Results: There was no correlation found between the residency program director's gender and the gender diversity of residents in a given program. The percentage of women faculty identified on a department website was significantly correlated with the percentage of women residents in the program, regardless of the program director's gender. While there was an increase in the percentage of women residents among programs with Instagram accounts for the class that started in 2021, this was negated when the percentage of women faculty was taken into account. Conclusion: Efforts on multiple fronts will be needed to increase the number and percentage of women applying for and training in orthopedic surgery. Given the increasing use of digital media, we need a better understanding of what information, including faculty gender diversity, can be conveyed through this format that is useful for women medical students interested in orthopedic surgery to address their concerns about the field.

3.
Exp Ther Med ; 22(5): 1295, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34630650

RESUMO

Glutamate-induced excitotoxicity is a well-recognized cause of neuronal cell death. Nutritional supplementation with Coenzyme Q10 (CoQ10) has been previously demonstrated to serve neuro-protective effects against glutamate-induced excitotoxicity. The aim of the present study was to determine whether the protective effect of CoQ10 against glutamate toxicity could be attributed to stimulating mitochondrial biogenesis. Mouse hippocampal neuronal HT22 cells were incubated with glutamate with or without ubisol Q10. The results revealed that glutamate significantly decreased levels of mitochondrial biogenesis related proteins, including peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α and nuclear respiratory factor (NRF)2. Additionally, glutamate reduced mitochondrial biogenesis, as determined using a mitochondrial biogenesis kit. Pretreatment with CoQ10 prevented decreases in phosphorylated (p)-Akt, p-cAMP response element-binding protein, PGC-1α, NRF2 and mitochondrial transcription factor A, increasing mitochondrial biogenesis. Taken together, the results described a novel mechanism of CoQ10-induced neuroprotection and indicated a central role for mitochondrial biogenesis in protecting against glutamate-induced excitotoxicity.

4.
Pediatr Blood Cancer ; 68(8): e28930, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33565268

RESUMO

BACKGROUND: Ependymoma is the third most common malignant CNS tumor in children. Despite multimodal therapy, prognosis of relapsed ependymoma remains poor. Approaches to therapy for relapsed ependymoma are varied. We present a single-institution retrospective review of the outcomes after first relapse of intracranial ependymoma in children. PROCEDURE: We performed a retrospective, IRB-approved chart review of patients with recurrent intracranial ependymoma treated at Dana-Farber/Boston Children's Cancer and Blood Disorders Center from 1990 to 2019. RESULTS: Thirty-four patients with relapsed intracranial ependymoma were identified. At initial diagnosis, 11 patients had supratentorial disease, 22 with posterior fossa disease and one with metastatic disease. Median time-to-first relapse was 14.9 months from initial diagnosis (range 1.4-52.5). Seven patients had metastatic disease at first relapse. Gross total resection (GTR) was associated with improved 5-year progression-free survival (PFS) relative to subtotal resection (STR) and no surgery (p = .005). Localized disease at relapse was associated with improved 5-year overall survival (OS) when compared to metastatic disease (p = .02). Irradiation at first relapse seemed to delay progression but was not associated with statistically prolonged PFS or OS. Tumor location, histology, and chromosomal 1q status did not impact outcome at first relapse, although available molecular data were limited making definitive conclusions difficult. Median time-to-second relapse was 10 months (range 0.7-124). Five-year PFS and OS after first relapse were 19.9% and 45.1%, respectively. Median PFS and OS were 10.0 and 52.5 months after first relapse, respectively. CONCLUSIONS: Relapsed intracranial ependymoma has a poor prognosis despite multimodal therapy. Novel therapeutic strategies are desperately needed for this disease.


Assuntos
Neoplasias Encefálicas , Ependimoma , Neoplasias Encefálicas/terapia , Pré-Escolar , Doença Crônica , Ependimoma/terapia , Humanos , Lactente , Recidiva Local de Neoplasia/terapia , Estudos Retrospectivos
5.
Int J Med Sci ; 17(17): 2831-2843, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162811

RESUMO

Mammalian target of rapamycin (mTOR) is upregulated in a high percentage of glioblastomas. While a well-known mTOR inhibitor, rapamycin, has been shown to reduce glioblastoma survival, the role of mitochondria in achieving this therapeutic effect is less well known. Here, we examined mitochondrial dysfunction mechanisms that occur with the suppression of mTOR signaling. We found that, along with increased apoptosis, and a reduction in transformative potential, rapamycin treatment significantly affected mitochondrial health. Specifically, increased production of reactive oxygen species (ROS), depolarization of the mitochondrial membrane potential (MMP), and altered mitochondrial dynamics were observed. Furthermore, we verified the therapeutic potential of rapamycin-induced mitochondrial dysfunction through co-treatment with temzolomide (TMZ), the current standard of care for glioblastoma. Together these results demonstrate that the mitochondria remain a promising target for therapeutic intervention against human glioblastoma and that TMZ and rapamycin have a synergistic effect in suppressing glioblastoma viability, enhancing ROS production, and depolarizing MMP.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Sirolimo/farmacologia , Temozolomida/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Glioblastoma/patologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Temozolomida/uso terapêutico
6.
J Neurooncol ; 149(2): 253-262, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32780261

RESUMO

PURPOSE: Pediatric low-grade gliomas (pLGGs) are the most common CNS tumor of childhood and comprise a heterogenous group of tumors. Children with progressive pLGG often require numerous treatment modalities including surgery, chemotherapy, rarely radiation therapy and, more recently, molecularly targeted therapy. We describe our institutional experience using the MEK inhibitor, trametinib, for recurrent/progressive pLGGs. METHODS: We performed a retrospective, IRB-approved, chart review of all pediatric patients treated with trametinib for recurrent/progressive pLGGs at Dana-Farber/Boston Children's Cancer and Blood Disorder Center between 2016 and 2018. RESULTS: Eleven patients were identified, of which 10 were evaluable for response. Median age at commencement of trametinib treatment was 14.7 years (range 7.3-25.9 years). Tumor molecular status included KIAA1549-BRAF fusion (n = 4), NF1 mutation (n = 4), FGFR mutation (n = 1) and CDKN2A loss (n = 1). Median number of prior treatment regimens was 5 (range 1-12). Median duration of treatment with trametinib was 19.2 months (range 3.8-29.8 months). Based on modified RANO criteria, best responses included partial (n = 2), minor response (n = 2) and stable disease (n = 6). Two patients remain on therapy (29.8 and 25.9 months, respectively). The most common toxicities attributable to trametinib were rash, fatigue and gastrointestinal disturbance. Five patients required dose reduction for toxicities. Two patients experienced significant intracranial hemorrhage (ICH) while on trametinib. While it is unclear whether ICH was directly attributable to trametinib, therapy was discontinued. CONCLUSION: Trametinib appears to be an effective treatment for patients with recurrent/progressive pLGG. The toxicities of this therapy warrant further investigation, with particular attention to the potential risk for intracranial hemorrhage. Early phase multi-institutional clinical trials are underway.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Criança , Feminino , Seguimentos , Glioma/patologia , Humanos , Masculino , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
7.
J Neurooncol ; 149(1): 113-122, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32627129

RESUMO

INTRODUCTION: Immune checkpoint inhibition through PD-1 and CTLA-4 blockade has shown efficacy in some adult malignancies and generated interest in pediatrics, including central nervous system (CNS) tumors. We describe our experience with immune checkpoint inhibition in recurrent/refractory pediatric CNS tumors. METHODS: We performed a retrospective chart review of pediatric patients with recurrent or refractory CNS tumors treated with ipilimumab, nivolumab and/or pembrolizumab at Dana-Farber/Boston Children's Hospital between 2018 and 2019. RESULTS: Eleven patients were identified. Diagnoses included diffuse intrinsic pontine glioma (DIPG) (n = 2), high-grade glioma (HGG) (n = 5), ependymoma (n = 1), craniopharyngioma (n = 1), high-grade neuroepithelial tumor (n = 1) and non-germinomatous germ cell tumor (NGGCT) (n = 1). Eight patients had recurrent disease, while three had refractory disease. Nine patients received combination therapy (ipilimumab/nivolumab); two patients received either nivolumab or pembrolizumab. Median time from diagnosis-to-treatment was 8 months (range 0.8-156). All patients received prior radiation therapy (RT), with median time from RT-to-immunotherapy was 3.8 years. One patient received concurrent then adjuvant immunotherapy with RT. Median duration of treatment was 6.1 months (range 1-25). Therapy was discontinued in nine patients: seven due to disease progression and two due to toxicity (colitis; transaminitis). Other pertinent toxicities included Type 1 diabetes mellitus, hypothyroidism and skin toxicity. Based on iRANO criteria, best responses included partial response (n = 3), stable disease (n = 7) and progressive disease (n = 1). Durable response was noted in two patients. CONCLUSION: Immune checkpoint inhibition was relatively well tolerated in a cohort of pediatric patients spanning several CNS tumor diagnoses. Results from prospective clinical trials will be critical to inform clinical decisions.


Assuntos
Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Adolescente , Adulto , Neoplasias do Sistema Nervoso Central/imunologia , Neoplasias do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
8.
BMC Neurosci ; 19(1): 82, 2018 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-30594149

RESUMO

BACKGROUND: Cobalt chloride (CoCl2) induces chemical hypoxia through activation of hypoxia-inducible factor-1 alpha (HIF-1α). Mammalian target of rapamycin (mTOR) is a multifaceted protein capable of regulating cell growth, angiogenesis, metabolism, proliferation, and survival. In this study, we tested the efficacy of a well-known mTOR inhibitor, rapamycin, in reducing oxidative damage and increasing cell viability in the mouse hippocampal cell line, HT22, during a CoCl2-simulated hypoxic insult. RESULTS: CoCl2 caused cell death in a dose-dependent manner and increased protein levels of cleaved caspase-9 and caspase-3. Rapamycin increased viability of HT22 cells exposed to CoCl2 and reduced activation of caspases-9 and -3. Cells exposed to CoCl2 displayed increased reactive oxygen species (ROS) production and hyperpolarization of the mitochondrial membrane, both of which rapamycin successfully blocked. mTOR protein itself, along with its downstream signaling target, phospho-S6 ribosomal protein (pS6), were significantly inhibited with CoCl2 and rapamycin addition did not significantly lower expression further. Rapamycin promoted protein expression of Beclin-1 and increased conversion of microtubule-associated protein light chain 3 (LC3)-I into LC3-II, suggesting an increase in autophagy. Pro-apoptotic protein, Bcl-2 associated × (Bax), exhibited a slight, but significant decrease with rapamycin treatment, while its anti-apoptotic counterpart, B cell lymphoma-2 (Bcl-2), was to a similar degree upregulated. Finally, the protein expression ratio of phosphorylated mitogen-activated protein kinase (pMAPK) to its unphosphorylated form (MAPK) was dramatically increased in rapamycin and CoCl2 co-treated cells. CONCLUSIONS: Our results indicate that rapamycin confers protection against CoCl2-simulated hypoxic insults to neuronal cells. This occurs, as suggested by our results, independent of mTOR modification, and rather through stabilization of the mitochondrial membrane with concomitant decreases in ROS production. Additionally, inhibition of caspase-9 and -3 activation and stimulation of protective autophagy reduces cell death, while a decrease in the Bax/Bcl-2 ratio and an increase in pMAPK promotes cell survival during CoCl2 exposure. Together these results demonstrate the therapeutic potential of rapamycin against hypoxic injury and highlight potential pathways mediating the protective effects of rapamycin treatment.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Cobalto/toxicidade , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Sirolimo/farmacologia , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Hipocampo/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Proteína X Associada a bcl-2/metabolismo
9.
Int J Med Sci ; 15(12): 1384-1396, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30275767

RESUMO

Cerebral hypoxia as often occurs in cases of stroke, hemorrhage, or other traumatic brain injuries, is one of the leading causes of death worldwide and a main driver of disabilities in the elderly. Using a chemical mimetic of hypoxia, cobalt chloride (CoCl2), we tested the ability of a novel small molecule, 4-chloro-N-(naphthalen-1-ylmethyl)-5-(3-(piperazin-1-yl)phenoxy)thiophene-2-sulfonamide (B355252), to alleviate CoCl2-induced damage in mouse hippocampal HT22 cells. A dose-dependent decrease in cell viability was observed during CoCl2 treatment along with increases in mitochondrial membrane potential and generation of reactive oxygen species (ROS). B355252 conferred protection against these changes. We further found that mitochondrial dynamics, the balance between mitochondrial fusion and fission, were perturbed by CoCl2 treatment. Mitochondrial fusion, which was assessed by measuring the expression of proteins optic atrophy protein 1 (OPA1) and mitofusin 2 (Mfn2), declined due to CoCl2 exposure, but B355252 addition was able to elevate Mfn2 expression while OPA1 expression was unchanged. Mitochondrial fission, measured by phosphorylated dynamin-related protein 1 (p-DRP1) and fission protein 1 (FIS1) expression, also decreased following CoCl2 exposure, and was stabilized by B355252 addition. Finally, autophagy was assessed by measuring the conversion of cytosolic microtubule-associated protein 1A/1B-light chain three-I (LC3-I) to autophagosome-bound microtubule-associated protein 1A/1B-light chain three-II (LC3-II) and was found to be increased by CoCl2. B355252 addition significantly reduced autophagy induction. Taken together, our results indicate B355252 has therapeutic potential to reduce the damaging effects caused by CoCl2 and should be further evaluated for applications in cerebral ischemia therapy.


Assuntos
Autofagia/efeitos dos fármacos , Cobalto/toxicidade , Hipocampo/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Tiofenos/farmacologia , Animais , Camundongos , Mitocôndrias , Neuroproteção , Espécies Reativas de Oxigênio
10.
Disabil Health J ; 10(3): 419-425, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28487170

RESUMO

BACKGROUND: Women with disabilities report fewer pregnancies than those without disabilities. OBJECTIVE: To explore the range of factors involved in pregnancy decision-making among women with disabilities, and give insight into the decision making process. METHODS: Data were obtained from 4 focus groups conducted with 22 women of child-bearing age, who had a chronic physical or mental health condition or disability that influenced their pregnancy decisions. Group transcripts were analyzed using conventional content analysis to identify the types of factors that influence pregnancy decisions and themes related to pregnancy decision-making. RESULTS: Most had a strong desire for motherhood, although there were varied decisions and some ambivalence over whether or not to attempt pregnancy. Decisions were influenced by an interplay of biomedical, social and personal factors that shaped assessments of three key areas of consideration: importance, feasibility, and costs of pregnancy/motherhood. CONCLUSIONS: It is not just the 'biomedical facts' of health conditions that are relevant, but rather the meaning attributed to these facts and how they are weighed in relation to other significant non-medical factors. By moving beyond the medical model of disability to recognize the importance of social and personal factors, and engaging in patient-centered communication, healthcare providers can facilitate pregnancy decision-making that is consistent with the values and preferences of women with disabilities and improve quality of care and support. In order to make motherhood a more viable option for women with disabilities, societal attitudes and a lack of role models for these women also need to be addressed.


Assuntos
Tomada de Decisões , Pessoas com Deficiência/psicologia , Pessoas com Deficiência/estatística & dados numéricos , Mães/estatística & dados numéricos , Comportamento Reprodutivo/psicologia , Comportamento Reprodutivo/estatística & dados numéricos , Adolescente , Adulto , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Kansas , Mães/psicologia , Gravidez , Adulto Jovem
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