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1.
Curr Pharm Des ; 27(17): 1977-1991, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719968

RESUMO

Liposomes are nano-sized formulations having the benefits of site-specificity, biocompatibility, and biodegradability, which make them useful for the therapy and diagnosis of major diseases like cancer. In this review, various synthetic strategies of liposomes and their biomedical application in special concern to cancer are discussed. In context to the biomedical application, this article gives a detailed insight into subcellular targeted therapy and several therapeutic modifications like immunotherapy, receptor-based therapy, phototherapy, and combination therapy. The review also describes the liposome-based imaging platforms and the toxicity associated with liposomes. Owing to a significant amount of benefits of this carrier system, several products have been approved to be launched in the market and several others have already been marketed for clinical use.


Assuntos
Lipossomos , Neoplasias , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Medicina de Precisão , Nanomedicina Teranóstica
2.
Nat Immunol ; 20(8): 1023-1034, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31263278

RESUMO

Stroke is a multiphasic process in which initial cerebral ischemia is followed by secondary injury from immune responses to ischemic brain components. Here we demonstrate that peripheral CD11b+CD45+ myeloid cells magnify stroke injury via activation of triggering receptor expressed on myeloid cells 1 (TREM1), an amplifier of proinflammatory innate immune responses. TREM1 was induced within hours after stroke peripherally in CD11b+CD45+ cells trafficking to ischemic brain. TREM1 inhibition genetically or pharmacologically improved outcome via protective antioxidant and anti-inflammatory mechanisms. Positron electron tomography imaging using radiolabeled antibody recognizing TREM1 revealed elevated TREM1 expression in spleen and, unexpectedly, in intestine. In the lamina propria, noradrenergic-dependent increases in gut permeability induced TREM1 on inflammatory Ly6C+MHCII+ macrophages, further increasing epithelial permeability and facilitating bacterial translocation across the gut barrier. Thus, following stroke, peripheral TREM1 induction amplifies proinflammatory responses to both brain-derived and intestinal-derived immunogenic components. Critically, targeting this specific innate immune pathway reduces cerebral injury.


Assuntos
Encéfalo/imunologia , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Neutrófilos/imunologia , Acidente Vascular Cerebral/patologia , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Animais , Encéfalo/citologia , Linhagem Celular , Imunidade Inata/imunologia , Inflamação/patologia , Mucosa Intestinal/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células RAW 264.7
3.
Lung India ; 36(Supplement): S37-S89, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32445309

RESUMO

Flexible bronchoscopy (FB) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. However, bronchoscopy practices vary widely across India and worldwide. The three major respiratory organizations of the country supported a national-level expert group that formulated a comprehensive guideline document for FB based on a detailed appraisal of available evidence. These guidelines are an attempt to provide the bronchoscopist with the most scientifically sound as well as practical approach of bronchoscopy. It involved framing appropriate questions, review and critical appraisal of the relevant literature and reaching a recommendation by the expert groups. The guidelines cover major areas in basic bronchoscopy including (but not limited to), indications for procedure, patient preparation, various sampling procedures, bronchoscopy in the ICU setting, equipment care, and training issues. The target audience is respiratory physicians working in India and well as other parts of the world. It is hoped that this document would serve as a complete reference guide for all pulmonary physicians performing or desiring to learn the technique of flexible bronchoscopy.

4.
J Neurosurg Pediatr ; 22(4): 404-410, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30028275

RESUMO

OBJECTIVE: Pediatric spinal astrocytomas are rare spinal lesions that pose unique management challenges. Therapeutic options include gross-total resection (GTR), subtotal resection (STR), and adjuvant chemotherapy or radiation therapy. With no randomized controlled trials, the optimal management approach for children with spinal astrocytomas remains unclear. The aim of this study was to conduct a systematic review and meta-analysis on pediatric spinal astrocytomas. METHODS: The authors performed a systematic review of the PubMed/MEDLINE electronic database to investigate the impact of histological grade and extent of resection on overall survival among patients with spinal cord astrocytomas. They retained publications in which the majority of reported cases included astrocytoma histology. RESULTS: Twenty-nine previously published studies met the eligibility criteria, totaling 578 patients with spinal cord astrocytomas. The spinal level of intramedullary spinal cord tumors was predominantly cervical (53.8%), followed by thoracic (40.8%). Overall, resection was more common than biopsy, and GTR was slightly more commonly achieved than STR (39.7% vs 37.0%). The reported rates of GTR and STR rose markedly from 1984 to 2015. Patients with high-grade astrocytomas had markedly worse 5-year overall survival than patients with low-grade tumors. Patients receiving GTR may have better 5-year overall survival than those receiving STR. CONCLUSIONS: The authors describe trends in the management of pediatric spinal cord astrocytomas and suggest a benefit of GTR over STR for 5-year overall survival.


Assuntos
Astrocitoma/cirurgia , Neoplasias da Medula Espinal/cirurgia , Adolescente , Astrocitoma/mortalidade , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos , Neoplasias da Medula Espinal/mortalidade , Resultado do Tratamento
5.
World Neurosurg ; 113: e399-e407, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29454124

RESUMO

BACKGROUND: CyberKnife stereotactic radiosurgery (SRS) for trigeminal neuralgia (TGN) administers nonisometric, conformational high-dose radiation to the trigeminal nerve with risk of subsequent hypoesthesia. METHODS: We performed a retrospective, single-institution review of 66 patients with TGN treated with CyberKnife SRS to compare outcomes from 2 distinct treatment periods: standard dosing (n = 38) and reduced dosing (n = 28). Standard and reduced dosing permitted a maximum brainstem dose of 45 Gy and 25 Gy, respectively, each with a prescription dose of 60 Gy. Primary and secondary outcomes were Barrow Neurologic Institute pain and numbness scores. Maximum brainstem dose, prepontine nerve length, and treatment history were recorded for their predictive contributions by logistic regression. RESULTS: After matching, patients in the standard dosing and reduced dosing groups were followed for a median of 25 months and 19.5 months, respectively. Mean trigeminal nerve length was 8.55 mm in the standard dosing group and 9.46 mm in the reduced dosing group. Baseline rates of poorly controlled pain were 97% and 88%, respectively, which improved to 23.4% and 8.3%, respectively (P < 0.001 for both). The baseline rates of bothersome numbness were null in both groups, and increased to 25% in the standard group (P = 0.006) and to 21% in the reduced group (P = 0.07). Regression analyses suggested that reduced brainstem exposure (P = 0.01), as well as a longer trigeminal nerve (P = 0.01), were predictive of durable pain control. CONCLUSIONS: These outcomes demonstrate that a lower maximum brainstem dose can provide excellent pain control without affecting facial numbness. Longer nerves may achieve better long-term outcomes and help optimize individual plans.


Assuntos
Tronco Encefálico/efeitos da radiação , Radiocirurgia , Neuralgia do Trigêmeo/cirurgia , Idoso , Antropometria , Estudos de Casos e Controles , Relação Dose-Resposta à Radiação , Feminino , Humanos , Hipestesia/etiologia , Masculino , Pessoa de Meia-Idade , Parestesia/etiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Lesões por Radiação/prevenção & controle , Radiometria , Estudos Retrospectivos , Nervo Trigêmeo/patologia , Doenças do Nervo Trigêmeo/etiologia
6.
Clin Neurol Neurosurg ; 163: 1-8, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29028584

RESUMO

Radiation serves an important role in the treatment of metastatic and primary brain tumors. Radiation carries a risk of post radiation treatment effects, such as pseudoprogression and radiation necrosis. The ability to differentiate between radiation necrosis, pseudoprogression, and tumor recurrence remains a diagnostic conundrum with varying treatment options. In this review, we will discuss the pathophysiology, diagnostic imaging modalities, and treatments of these post-radiation treatment effects. We focus on the latest developments in magnetic resonance imaging (MRI) modalities including imaging biomarkers and the newest therapeutics such as VEGF inhibitors, Hyperbaric Oxygen Therapy, sensitized cytotoxic T cells, and Laser Interstitial Thermal Therapy (LITT).


Assuntos
Neoplasias Encefálicas/terapia , Recidiva Local de Neoplasia/terapia , Lesões por Radiação/diagnóstico , Lesões por Radiação/terapia , Radiocirurgia , Neoplasias Encefálicas/diagnóstico , Progressão da Doença , Humanos , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Recidiva Local de Neoplasia/diagnóstico , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos
7.
Biomaterials ; 142: 31-40, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28719819

RESUMO

Exogenous human neural progenitor cells (hNPCs) are promising stroke therapeutics, but optimal delivery conditions and exact recovery mechanisms remain elusive. To further elucidate repair processes and improve stroke outcomes, we developed an electrically conductive, polymer scaffold for hNPC delivery. Electrical stimulation of hNPCs alters their transcriptome including changes to the VEGF-A pathway and genes involved in cell survival, inflammatory response, and synaptic remodeling. In our experiments, exogenous hNPCs were electrically stimulated (electrically preconditioned) via the scaffold 1 day prior to implantation. After in vitro stimulation, hNPCs on the scaffold are transplanted intracranially in a distal middle cerebral artery occlusion rat model. Electrically preconditioned hNPCs improved functional outcomes compared to unstimulated hNPCs or hNPCs where VEGF-A was blocked during in vitro electrical preconditioning. The ability to manipulate hNPCs via a conductive scaffold creates a new approach to optimize stem cell-based therapy and determine which factors (such as VEGF-A) are essential for stroke recovery.


Assuntos
Condutividade Elétrica , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/transplante , Polímeros/química , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Alicerces Teciduais/química , Animais , Infarto Encefálico/patologia , Estimulação Elétrica , Regulação da Expressão Gênica , Humanos , Masculino , Pirróis/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Nus , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Indian J Pathol Microbiol ; 59(1): 69-71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26960640

RESUMO

Liposarcomas are extremely rare in the mediastinum. Patients usually present late due to the compressive effect of the tumor on the adjacent structures. Severity of the symptoms depend mainly on the size of the tumor and the structure it infiltrates. Well differentiated slow growing liposarcomas are the most common ones in the mediastinum followed by dedifferentiated and poorly differentiated ones. These tumors have bad prognosis because of incomplete surgical excision due to its inaccessible location. Hence these patients should be kept under close follow up because of high recurrent rates. Here we are presenting a rare case of anterior mediastinal sclerosing liposarcoma in a 77 year old male.


Assuntos
Lipossarcoma/diagnóstico , Lipossarcoma/patologia , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/patologia , Mediastino/patologia , Idoso , Biomarcadores Tumorais/análise , Histocitoquímica , Humanos , Imuno-Histoquímica , Lipossarcoma/diagnóstico por imagem , Masculino , Neoplasias do Mediastino/diagnóstico por imagem , Microscopia , Radiografia Torácica , Proteínas S100/análise , Tomografia Computadorizada por Raios X
10.
Cancer Discov ; 4(11): 1326-41, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25186949

RESUMO

UNLABELLED: Pediatric Ewing sarcoma is characterized by the expression of chimeric fusions of EWS and ETS family transcription factors, representing a paradigm for studying cancers driven by transcription factor rearrangements. In this study, we describe the somatic landscape of pediatric Ewing sarcoma. These tumors are among the most genetically normal cancers characterized to date, with only EWS-ETS rearrangements identified in the majority of tumors. STAG2 loss, however, is present in more than 15% of Ewing sarcoma tumors; occurs by point mutation, rearrangement, and likely nongenetic mechanisms; and is associated with disease dissemination. Perhaps the most striking finding is the paucity of mutations in immediately targetable signal transduction pathways, highlighting the need for new therapeutic approaches to target EWS-ETS fusions in this disease. SIGNIFICANCE: We performed next-generation sequencing of Ewing sarcoma, a pediatric cancer involving bone, characterized by expression of EWS-ETS fusions. We found remarkably few mutations. However, we discovered that loss of STAG2 expression occurs in 15% of tumors and is associated with metastatic disease, suggesting a potential genetic vulnerability in Ewing sarcoma.


Assuntos
Antígenos Nucleares/genética , Neoplasias Ósseas/genética , Sarcoma de Ewing/genética , Antígenos Nucleares/metabolismo , Neoplasias Ósseas/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Criança , DNA de Neoplasias/genética , Feminino , Rearranjo Gênico , Genômica , Humanos , Masculino , Mutação , Sarcoma de Ewing/metabolismo , Análise de Sequência de DNA
11.
Cancer Cell ; 25(2): 226-42, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24525236

RESUMO

Cooperative dependencies between mutant oncoproteins and wild-type proteins are critical in cancer pathogenesis and therapy resistance. Although spleen tyrosine kinase (SYK) has been implicated in hematologic malignancies, it is rarely mutated. We used kinase activity profiling to identify collaborators of SYK in acute myeloid leukemia (AML) and determined that FMS-like tyrosine kinase 3 (FLT3) is transactivated by SYK via direct binding. Highly activated SYK is predominantly found in FLT3-ITD positive AML and cooperates with FLT3-ITD to activate MYC transcriptional programs. FLT3-ITD AML cells are more vulnerable to SYK suppression than FLT3 wild-type counterparts. In a FLT3-ITD in vivo model, SYK is indispensable for myeloproliferative disease (MPD) development, and SYK overexpression promotes overt transformation to AML and resistance to FLT3-ITD-targeted therapy.


Assuntos
Transformação Celular Neoplásica , Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas Tirosina Quinases/metabolismo , Tirosina Quinase 3 Semelhante a fms/genética , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Western Blotting , Proliferação de Células , Células Cultivadas , Fluoruracila/farmacologia , Humanos , Técnicas Imunoenzimáticas , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Camundongos , Camundongos Endogâmicos BALB C , Mutação/genética , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Quinase Syk , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/metabolismo
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