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1.
Neuropathology ; 43(4): 333-339, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36642816

RESUMO

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by extensive heterotopic ossification of soft tissue structures leading to severe limitations in movement. FOP is caused by a germline mutation in the activating receptor type IA (ACVR1) gene. Worrisome is the fact that up to a third of diffuse intrinsic pontine gliomas (DIPG) also harbor the same point mutation in ACVR1. Radiological reports of central nervous system (CNS) involvement by FOP have described brainstem masses; however, the literature on the histopathology or pathogenesis of these lesions is scant. Here we present detailed neuropathologic findings of a brainstem mass in a patient with FOP and suggest that the tumor is hamartomatous in nature. This report, along with a literature review of radiographic and laboratory data, offers support for the idea that the ACVR1 mutation may incite CNS proliferation, predominantly in the brainstem, but is probably not an oncologic driver. These lesions may be seen at autopsy and are likely noncontributory to death.


Assuntos
Miosite Ossificante , Ossificação Heterotópica , Humanos , Miosite Ossificante/genética , Miosite Ossificante/patologia , Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Mutação , Mutação Puntual , Encéfalo/patologia , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo
2.
ACS Nano ; 16(6): 8729-8750, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35616289

RESUMO

Glioblastoma (GBM) is an aggressive primary brain cancer, with a 5 year survival of ∼5%. Challenges that hamper GBM therapeutic efficacy include (i) tumor heterogeneity, (ii) treatment resistance, (iii) immunosuppressive tumor microenvironment (TME), and (iv) the blood-brain barrier (BBB). The C-X-C motif chemokine ligand-12/C-X-C motif chemokine receptor-4 (CXCL12/CXCR4) signaling pathway is activated in GBM and is associated with tumor progression. Although the CXCR4 antagonist (AMD3100) has been proposed as an attractive anti-GBM therapeutic target, it has poor pharmacokinetic properties, and unfavorable bioavailability has hampered its clinical implementation. Thus, we developed synthetic protein nanoparticles (SPNPs) coated with the transcytotic peptide iRGD (AMD3100-SPNPs) to target the CXCL2/CXCR4 pathway in GBM via systemic delivery. We showed that AMD3100-SPNPs block CXCL12/CXCR4 signaling in three mouse and human GBM cell cultures in vitro and in a GBM mouse model in vivo. This results in (i) inhibition of GBM proliferation, (ii) reduced infiltration of CXCR4+ monocytic myeloid-derived suppressor cells (M-MDSCs) into the TME, (iii) restoration of BBB integrity, and (iv) induction of immunogenic cell death (ICD), sensitizing the tumor to radiotherapy and leading to anti-GBM immunity. Additionally, we showed that combining AMD3100-SPNPs with radiation led to long-term survival, with ∼60% of GBM tumor-bearing mice remaining tumor free after rechallenging with a second GBM in the contralateral hemisphere. This was due to a sustained anti-GBM immunological memory response that prevented tumor recurrence without additional treatment. In view of the potent ICD induction and reprogrammed tumor microenvironment, this SPNP-mediated strategy has a significant clinical translation applicability.


Assuntos
Glioblastoma , Glioma , Imunoterapia , Nanopartículas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CXCL12/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioma/tratamento farmacológico , Receptores CXCR4/antagonistas & inibidores , Transdução de Sinais , Microambiente Tumoral
3.
Mol Cell Oncol ; 8(2): 1870647, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33855166

RESUMO

Glioblastoma is an aggressive brain tumor with poor prognosis. The brain is protected by the blood-brain barrier, which precludes transport of chemotherapeutics. We developed nanoparticles that achieve delivery of small-interfering RNA against Stat3 after systemic administration. Nanoparticles combined with radiation inhibited tumor progression and elicited anti-glioblastoma immunity in mice.

4.
Clin Imaging ; 73: 139-145, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33406475

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common primary brain malignancy, but much remains unknown about the histogenesis of these tumors. In the great majority of cases, GBM is a purely glial tumor but in rare cases the classic-appearing high-grade glioma component is admixed with regions of small round blue cells with neuronal immunophenotype, and these tumors have been defined in the WHO 2016 Classification as "glioblastoma with a primitive neuronal component." METHODS: In this paper, we present two cases of GBM-PNC with highly divergent clinical courses, and review current theories for the GBM cell-of-origin. RESULTS AND CONCLUSIONS: GBM-PNC likely arises from a cell type competent to give rise to glial or neuronal lineages. The thesis that GBM recapitulates to some extent normal neurodevelopmental cellular pathways is supported by molecular and clinical features of our two cases of GBM-PNC, but more work is needed to determine which cellular precursor gives rise to specific cases of GBM. GBM-PNC may have a dramatically altered clinical course compared to standard GBM and may benefit from specific lines of treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagem , Glioblastoma/diagnóstico por imagem , Humanos
5.
Surg Neurol Int ; 11: 362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194295

RESUMO

BACKGROUND: Cervical myelopathy in an adult is typically the result of degenerative disease or trauma. Dysraphism is rarely the cause. CASE DESCRIPTION: The authors report the case of a 35-year-old male drywall installer who presented with 2 years of progressive left upper extremity weakness, numbness, and hand clumsiness. Only upon detailed questioning did he mention that he had neck surgery just after birth, but he did not know what was done. He then also reported that he routinely shaved a patch of lower back hair, but denied bowel, bladder, or lower extremity dysfunction. Magnetic resonance imaging of the cervical spine demonstrated T2 hyperintensity at C4-C5 with dorsal projection of the neural elements into the subcutaneous tissues concerning for a retethered cervical myelomeningocele. Lumbar imaging revealed a diastematomyelia at L4. He underwent surgical intervention for detethering and repaired of the cervical myelomeningocele. Four months postoperatively, he had almost complete resolution of symptoms, and imaging showed a satisfactory detethering. The diastematomyelia remained asymptomatic and is being observed. CONCLUSION: Tethered cervical cord is a rare cause for myelopathy in the adult patient. In the symptomatic patient, surgical repair with detethering is indicated to prevent disease progression and often results in clinical improvement.

6.
Nat Commun ; 11(1): 5687, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173024

RESUMO

Glioblastoma (GBM), the most aggressive form of brain cancer, has witnessed very little clinical progress over the last decades, in part, due to the absence of effective drug delivery strategies. Intravenous injection is the least invasive drug delivery route to the brain, but has been severely limited by the blood-brain barrier (BBB). Inspired by the capacity of natural proteins and viral particulates to cross the BBB, we engineered a synthetic protein nanoparticle (SPNP) based on polymerized human serum albumin (HSA) equipped with the cell-penetrating peptide iRGD. SPNPs containing siRNA against Signal Transducer and Activation of Transcription 3 factor (STAT3i) result in in vitro and in vivo downregulation of STAT3, a central hub associated with GBM progression. When combined with the standard of care, ionized radiation, STAT3i SPNPs result in tumor regression and long-term survival in 87.5% of GBM-bearing mice and prime the immune system to develop anti-GBM immunological memory.


Assuntos
Sistemas de Liberação de Medicamentos , Glioblastoma/tratamento farmacológico , Nanopartículas , Fator de Transcrição STAT3/metabolismo , Animais , Barreira Hematoencefálica , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Inativação Gênica , Humanos , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética
7.
Adv Healthc Mater ; 9(21): e2000564, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32959525

RESUMO

Delivery of multiple therapeutics has become a preferred method of treating cancer, albeit differences in the biodistribution and pharmacokinetic profiles of individual drugs pose challenges in effectively delivering synergistic drug combinations to and at the tumor site. Here, bicompartmental Janus nanoparticles comprised of domains are reported with distinct bulk properties that allow for independent drug loading and release. Programmable drug release can be triggered by a change in the pH value and depends upon the bulk properties of the polymers used in the respective compartments, rather than the molecular structures of the active agents. Bicompartmental nanoparticles delivering a synergistic combination of lapatinib and paclitaxel result in increased activity against HER2+ breast cancer cells. Surprisingly, the dual drug loaded particles also show significant efficacy toward triple negative breast cancer, even though this cancer model is unresponsive to lapatinib alone. The broad versatility of the nanoparticle platform allows for rapid exploration of a wide range of drug combinations where both their relative drug ratios and temporal release profiles can be optimized.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica , Linhagem Celular Tumoral , Combinação de Medicamentos , Sistemas de Liberação de Medicamentos , Humanos , Paclitaxel , Distribuição Tecidual
8.
Open Forum Infect Dis ; 7(7): ofaa189, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32715017

RESUMO

Granulomatous amoebic encephalitis (GAE) caused by Balamuthia mandrillaris is a rare subacute infection with exceptionally high mortality. Diagnosis is typically made by brain biopsy or at autopsy. Detection of Balamuthia mandrillaris cell-free DNA by next-generation sequencing of plasma enabled rapid, noninvasive diagnosis in a case of amoebic encephalitis.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32196991

RESUMO

Clinical translation of nanoparticle-based drug delivery systems is hindered by an array of challenges including poor circulation time and limited targeting. Novel approaches including designing multifunctional particles, cell-mediated delivery systems, and fabrications of protein-based nanoparticles have gained attention to provide new perspectives to current drug delivery obstacles in the interdisciplinary field of nanomedicine. Collectively, these nanoparticle devices are currently being investigated for applications spanning from drug delivery and cancer therapy to medical imaging and immunotherapy. Here, we review the current state of the field, highlight opportunities, identify challenges, and present the future directions of the next generation of multifunctional nanoparticle drug delivery platforms. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.


Assuntos
Nanopartículas Multifuncionais/uso terapêutico , Nanomedicina , Anisotropia , Ensaios Clínicos como Assunto , Humanos , Nanopartículas/química , Proteínas/química
10.
J Trauma Acute Care Surg ; 83(1): 25-29, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28452877

RESUMO

With a relative shortage of type AB plasma, many centers have converted to type A plasma for resuscitation of patients whose blood type is unknown. The goal of this study is to determine outcomes for trauma patients who received incompatible plasma transfusions as part of a massive transfusion protocol (MTP). METHODS: As part of an Eastern Association for the Surgery of Trauma multi-institutional trial, registry and blood bank data were collected from eight trauma centers for trauma patients (age, ≥ 15 years) receiving emergency release plasma transfusions as part of MTPs from January 2012 to August 2016. Incompatible type A plasma was defined as transfusion to patient blood type B or type AB. RESULTS: Of the 1,536 patients identified, 92% received compatible plasma transfusions and 8% received incompatible type A plasma. Patient characteristics were similar except for greater penetrating injuries (48% vs 36%; p = 0.01) in the incompatible group. In the incompatible group, patients were transfused more plasma units at 4 hours (median, 9 vs. 5; p < 0.001) and overall for stay (11 vs. 9; p = 0.03). No hemolytic transfusion reactions were reported. Two transfusion-related acute lung injury events were reported in the compatible group. Between incompatible and compatible groups, there was no difference in the rates of acute respiratory distress syndrome (6% vs. 8%; p = 0.589), thromboembolic events (9% vs. 7%; p = 0.464), sepsis (6% vs. 8%; p = 0.589), or acute renal failure (8% vs. 8%, p = 0.860). Mortality at 6 (17% vs. 15%, p = 0.775) and 24 hours (25% vs. 23%, p = 0.544) and at 28 days or discharge (38% vs. 35%, p = 0.486) were similar between groups. Multivariate regression demonstrated that Injury Severity Score, older age and more red blood cell transfusion at 4 hours were independently associated with death at 28 days or discharge; Injury Severity Score and more red blood cell transfusion at 4 hours were predictors for morbidity. Incompatible transfusion was not an independent determinant of mortality or morbidity. CONCLUSION: Transfusion of type A plasma to patients with blood groups B and AB as part of a MTP does not appear to be associated with significant increases in morbidity or mortality. LEVEL OF EVIDENCE: Therapeutic study, level IV.


Assuntos
Transfusão de Componentes Sanguíneos/métodos , Incompatibilidade de Grupos Sanguíneos , Hemorragia/terapia , Plasma , Ressuscitação/métodos , Ferimentos e Lesões/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemorragia/mortalidade , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Centros de Traumatologia , Resultado do Tratamento , Estados Unidos , Ferimentos e Lesões/mortalidade
11.
Case Rep Oncol ; 9(3): 661-665, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27920699

RESUMO

Multiple lymphomatous polyposis (MLP) as an extranodal manifestation of mantle cell lymphoma (MCL) in the gastrointestinal tract is rare and not often reported in the literature. We describe the case of a 63-year-old female with asymptomatic MLP found during staging bidirectional endoscopy of MCL. The patient presented only with dyspnea, but was found on physical exam to have diffuse lymphadenopathy, and subsequent positron emission tomography (PET) CT showed extensive lymph node adenopathy consistent with lymphoma. Excisional lymph node biopsy revealed high-risk MCL. Prior to therapy, staging bidirectional endoscopy was performed, which revealed duodenal bulb polyps and diffuse polyposis in the colon. Biopsies showed atypical lymphoid infiltrate identical to the initial excisional lymph node biopsy. The patient underwent aggressive induction therapy, chemotherapy and bone marrow transplantation. Four months later, repeat colonoscopy and biopsies showed normal mucosa, and repeat PET CT showed no evidence of systemic disease. Eight months later, the patient began having symptoms consistent with cauda equina syndrome, and she was found to have leptomeningeal recurrence of MCL. In spite of other medical treatment, the patient's MCL progressed and she passed away 3 years after the initial presentation.

12.
J Virol ; 77(24): 13017-27, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14645558

RESUMO

The genome of foot-and-mouth disease virus (FMDV) differs from that of other picornaviruses in that it encodes a larger 3A protein (>50% longer than poliovirus 3A), as well as three copies of protein 3B (also known as VPg). Previous studies have shown that a deletion of amino acids 93 to 102 of the 153-codon 3A protein is associated with an inability of a Taiwanese strain of FMDV (O/TAW/97) to cause disease in bovines. Recently, an Asian virus with a second 3A deletion (amino acids 133 to 143) has also been detected (N. J. Knowles et al., J. Virol. 75:1551-1556, 2001). Genetically engineered viruses harboring the amino acids 93 to 102 or 133 to 143 grew well in porcine cells but replicated poorly in bovine cells, whereas a genetically engineered derivative of the O/TAW/97 virus expressing a full-length 3A (strain A12) grew well in both cell types. Interestingly, a virus with a deletion spanning amino acid 93 to 144 also grew well in porcine cells and caused disease in swine. Further, genetically engineered viruses containing only a single copy of VPg were readily recovered with the full-length 3A, the deleted 3A (amino acids 93 to 102), or the "super" deleted forms of 3A (missing amino acids 93 to 144). All of the single-VPg viruses were attenuated in porcine cells and replicated poorly in bovine cells. The single-VPg viruses produced a mild disease in swine, indicating that the VPg copy number is an important determinant of host range and virulence. The association of VPg copy number with increased virulence in vivo may help to explain why all naturally occurring FMDVs have retained three copies of VPg.


Assuntos
Vírus da Febre Aftosa/patogenicidade , Febre Aftosa/fisiopatologia , Doenças dos Suínos/fisiopatologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Animais , Bovinos , Linhagem Celular , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Deleção de Sequência , Especificidade da Espécie , Suínos , Doenças dos Suínos/virologia , Proteínas do Core Viral/genética , Virulência , Replicação Viral
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