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1.
J Neurooncol ; 140(3): 497-507, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30132163

RESUMO

INTRODUCTION: Emerging evidence suggests that effective treatment of glioblastoma (GBM), the most common and deadly form of adult primary brain cancer, will likely require concurrent treatment of multiple aspects of tumor pathobiology to overcome tumor heterogeneity and the complex tumor-supporting microenvironment. Recent studies in non-central nervous system (CNS) tumor cells have demonstrated that oxaliplatin (OXA) can induce multi-faceted anti-tumor effects, in particular at drug concentrations below those required to induce apoptosis. These findings motivated re-investigation of OXA for the treatment of GBM. METHODS: The effects of OXA on murine KR158 and GL261 glioma cells including cell growth, cell death, inhibition of signal transducer and activator of transcription (STAT) activity, O-6-methylguanine-DNA methyltransferase (MGMT) expression, and immunogenic cell death (ICD) initiation, were evaluated by cytotoxicity assays, Western blot analysis, STAT3-luciferase reporter assays, qRT-PCR assays, and flow cytometry. Chemical inhibitors of endoplasmic reticulum (ER) stress were used to investigate the contribution of this cell damage response to the observed OXA effects. The effect of OXA on bone marrow-derived macrophages (BMDM) exposed to glioma conditioned media (GCM) was also analyzed by Western blot analysis. RESULTS: We identified the OXA concentration threshold for induction of apoptosis and from this determined the drug dose and treatment period for sub-cytotoxic treatments of glioma cells. Under these experimental conditions, OXA reduced STAT3 activity, reduced MGMT levels and increased temozolomide sensitivity. In addition, there was evidence of immunogenic cell death (elevated EIF2α phosphorylation and calreticulin exposure) following prolonged OXA treatment. Notably, inhibition of ER stress reversed the OXA-mediated inhibition of STAT3 activity and MGMT expression in the tumor cells. In BMDMs exposed to GCM, OXA also reduced levels of phosphorylated STAT3 and decreased expression of Arginase 1, an enzyme known to contribute to pro-tumor functions in the tumor-immune environment. CONCLUSIONS: OXA can induce notable multi-faceted biological effects in glioma cells and BMDMs at relatively low drug concentrations. These findings may have significant therapeutic relevance against GBM and warrant further investigation.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Macrófagos/metabolismo , Oxaliplatina/farmacologia , Animais , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático , Glioma/tratamento farmacológico , Humanos , Macrófagos/efeitos dos fármacos , Camundongos , Fator de Transcrição STAT3/metabolismo , Temozolomida
2.
Resusc Plus ; 18: 100633, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38666251

RESUMO

Intro: Medical drones are an emerging technology which may facilitate rapid treatment in time-sensitive emergencies. However, drones rely on lay rescuers, whose interactions with multipurpose medical drones have not been studied, and the optimal drone design remains unclear. Methods: We conducted 24 simulations of adult out-of-hospital cardiac arrest (OHCA) and pediatric anaphylaxis with a prototype drone equipped with spoken and visual cues and a multipurpose medical kit. 24 layperson volunteers encountered one of the two scenarios and were supported through administering treatment by a simulated 911 dispatcher. Bystander-drone interactions were evaluated via a convergent parallel mixed methods approach using surveys, video event review, and semi-structured interviews. Results: 83% (20/24) of participants voiced comfort interacting with the drone. 96% (23/24) were interested in future interaction. Participants appreciated the drone's spoken instructions but found visual cues confusing. Participants retrieved the medical kit from the drone in a mean of 5 seconds (range 2-14) of drone contact; 79% (19/24) found this step easy or very easy. The medical kit's layered design caused difficulty in retrieving appropriate equipment. Participants expressed a wide range of reactions to the unique drone design. Conclusions: Laypeople can effectively and comfortably interact with a medical drone with a novel design. Feedback on design elements will result in further refinements and valuable insights for other drone designers. A multipurpose medical kit created more challenges and indicates the need for further refinement to facilitate use of the equipment.

3.
Resusc Plus ; 18: 100652, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38716383

RESUMO

Introduction: Medical drones have potential for improving the response times to out-of-hospital emergencies. However, widespread adoption is hindered by unanswered questions surrounding medical dispatch and bystander safety. This study evaluated the impact of novel drone-specific dispatch instructions (DSDI) on bystanders' ability to interact effectively with a medical drone and provide prompt, safe, and high-quality treatment in a simulated emergency scenario. We hypothesized DSDI would improve bystanders' performance and facilitate safer bystander-drone interactions. Methods: Twenty-four volunteers were randomized to receive either DSDI and standard Medical Priority Dispatch (MPD) instructions or MPD alone in a simulated out-of-hospital cardiac arrest (OHCA) or pediatric anaphylaxis.,3 Participants in the DSDI group received detailed instructions on locating and interacting with the drone and its enclosed medical kit. The simulations were video recorded. Participants completed a semi-structured interview and survey. Results: The addition of DSDI did not lead to statistically significant changes to the overall time to provide care in either the anaphylaxis or OHCA simulations. However, DSDI did have an impact on bystander safety. In the MPD only group, 50% (6/12) of participants ignored the audio and visual safety cues from the drone instead of waiting for it to be declared safe compared to no DSDI participants ignoring these safety cues. Conclusions: All participants successfully provided patient care. However, this study indicates that DSDI may be useful to ensure bystander safety and should be incorporated in the continued development of emergency medical drones.

4.
Curr Neuropharmacol ; 11(1): 16-29, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23814534

RESUMO

The neurological movement disorder dystonia is an umbrella term for a heterogeneous group of related conditions where at least 20 monogenic forms have been identified. Despite the substantial advances resulting from the identification of these loci, the function of many DYT gene products remains unclear. Comparative genomics using simple animal models to examine the evolutionarily conserved functional relationships with monogenic dystonias represents a rapid route toward a comprehensive understanding of these movement disorders. Current studies using the invertebrate animal models Caenorhabditis elegans and Drosophila melanogaster are uncovering cellular functions and mechanisms associated with mutant forms of the well-conserved gene products corresponding to DYT1, DYT5a, DYT5b, and DYT12 dystonias. Here we review recent findings from the invertebrate literature pertaining to molecular mechanisms of these gene products, torsinA, GTP cyclohydrolase I, tyrosine hydroxylase, and the alpha subunit of Na+/K ATPase, respectively. In each study, the application of powerful genetic tools developed over decades of intensive work with both of these invertebrate systems has led to mechanistic insights into these human disorders. These models are particularly amenable to large-scale genetic screens for modifiers or additional alleles, which are bolstering our understanding of the molecular functions associated with these gene products. Moreover, the use of invertebrate models for the evaluation of DYT genetic loci and their genetic interaction networks has predictive value and can provide a path forward for therapeutic intervention.

5.
Clin Pract Cases Emerg Med ; 7(2): 64-67, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37285498

RESUMO

INTRODUCTION: We present six adenovirus cases that emerged from a cluster of respiratory illnesses within a college population. Two patients required intensive care with complicated hospital courses and experienced residual symptoms. Four additional patients were evaluated in the emergency department (ED) with two additional diagnoses of neuroinvasive disease. These cases represent the first known occurrences of neuroinvasive adenovirus infections in healthy adults. CASE SERIES: An individual presented to the ED with fever, altered mental status, and seizures after being found unresponsive in his apartment. His presentation was concerning for significant central nervous system pathology. Shortly after his arrival, a second individual presented with similar symptoms. Both required intubation and admission to a critical care setting. Over a 24-hour period, four additional individuals presented to the ED with moderate severity symptoms. All six individuals tested positive for adenovirus in their respiratory secretions. A provisional diagnosis of neuroinvasive adenovirus was made after consultation with infectious diseases. CONCLUSION: This cluster of cases appears to represent the first known reported diagnosis of neuroinvasive adenovirus in healthy young individuals. Our cases were also unique in demonstrating a significant spectrum of disease severity. Over 80 individuals in the broader college community ultimately tested positive for adenovirus in respiratory samples. As respiratory viruses continue to challenge our healthcare systems, new spectrums of disease are being discovered. We believe clinicians should be aware of the potential severity of neuroinvasive adenovirus disease.

6.
Resusc Plus ; 13: 100347, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36654723

RESUMO

Interventions for many medical emergencies including cardiac arrests, strokes, drug overdoses, seizures, and trauma, are critically time-dependent, with faster intervention leading to improved patient outcomes. Consequently, a major focus of emergency medical services (EMS) systems and prehospital medicine has been improving the time until medical intervention in these time-sensitive emergencies, often by reducing the time required to deliver critical medical supplies to the scene of the emergency. Medical indications for using unmanned aerial vehicles, or drones, are rapidly expanding, including the delivery of time-sensitive medical supplies. To date, the drone-based delivery of a variety of time-critical medical supplies has been evaluated, generating promising data suggesting that drones can improve the time interval to intervention through the rapid delivery of automatic external defibrillators (AEDs), naloxone, antiepileptics, and blood products. Furthermore, the improvement in the time until intervention offered by drones in out-of-hospital emergencies is likely to improve patient outcomes in time-dependent medical emergencies. However, barriers and knowledge gaps remain that must be addressed. Further research demonstrating functionality in real-world scenarios, as well as research that integrates drones into the existing EMS structure will be necessary before drones can reach their full potential. The primary aim of this review is to summarize the current evidence in drone-based Emergency Medical Services Care to help identify future research directions.

7.
J Control Release ; 267: 144-153, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-28887134

RESUMO

The most common and deadly form of primary brain cancer, glioblastoma (GBM), is characterized by significant intratumoral heterogeneity, microvascular proliferation, immune system suppression, and brain tissue invasion. Delivering effective and sustained treatments to the invasive GBM cells intermixed with functioning neural elements is a major goal of advanced therapeutic systems for brain cancer. Previously, we investigated the nanoparticle characteristics that enable targeting of invasive GBM cells. This revealed the importance of minimizing non-specific binding within the relatively adhesive, 'sticky' microenvironment of the brain and brain tumors in particular. We refer to such nanoformulations with decreased non-specific adhesivity and receptor targeting as 'DART' therapeutics. In this work, we applied this information toward the design and characterization of biodegradable nanocarriers, and in vivo testing in orthotopic experimental gliomas. We formulated particulate nanocarriers using poly(lactic-co-glycolic acid) (PLGA) and PLGA-polyethylene glycol (PLGA-PEG) polymers to generate sub-100nm nanoparticles with minimal binding to extracellular brain components and strong binding to the Fn14 receptor - an upregulated, conserved component in invasive GBM. Multiple particle tracking in brain tissue slices and in vivo testing in orthotopic murine malignant glioma revealed preserved nanoparticle diffusivity and increased uptake in brain tumor cells. These combined characteristics also resulted in longer retention of the DART nanoparticles within the orthotopic tumors compared to non-targeted versions. Taken together, these results and nanoparticle design considerations offer promising new methods to optimize therapeutic nanocarriers for improving drug delivery and treatment for invasive brain tumors.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Glioma/tratamento farmacológico , Nanopartículas/administração & dosagem , Receptor de TWEAK/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacocinética , Encéfalo/metabolismo , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Proteínas da Matriz Extracelular/metabolismo , Glioma/metabolismo , Camundongos Endogâmicos C57BL , Nanopartículas/química , Poliésteres/administração & dosagem , Poliésteres/química , Poliésteres/farmacocinética , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética
8.
Oncoimmunology ; 5(9): e1208876, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27757301

RESUMO

Glioblastoma (GBM) is a fatal brain cancer for which new treatment options are sorely needed. Platinum-based drugs have been investigated extensively for GBM treatment but few have shown significant efficacy without major central nervous system (CNS) and systemic toxicities. The relative success of platinum drugs for treatment of non-CNS cancers indicates great therapeutic potential when effectively delivered to the tumor region(s). New insights into the broad anticancer effects of platinum drugs, particularly immunomodulatory effects, and innovative delivery strategies that can maximize these multi-modal effects and minimize toxicities may promote the re-purposing of this chemotherapeutic drug class for GBM treatment.

9.
Dis Model Mech ; 7(2): 233-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24311730

RESUMO

Molecular mechanisms underlying neurodegenerative diseases converge at the interface of pathways impacting cellular stress, protein homeostasis and aging. Targeting the intrinsic capacities of neuroprotective proteins to restore neuronal function and/or attenuate degeneration represents a potential means toward therapeutic intervention. The product of the human DYT1 gene, torsinA, is a member of the functionally diverse AAA+ family of proteins and exhibits robust molecular-chaperone-like activity, both in vitro and in vivo. Although mutations in DYT1 are associated with a rare form of heritable generalized dystonia, the native function of torsinA seems to be cytoprotective in maintaining the cellular threshold to endoplasmic reticulum (ER) stress. Here we explore the potential for torsinA to serve as a buffer to attenuate the cellular consequences of misfolded-protein stress as it pertains to the neurodegenerative disease amyotrophic lateral sclerosis (ALS). The selective vulnerability of motor neurons to degeneration in ALS mouse models harboring mutations in superoxide dismutase (SOD1) has been found to correlate with regional-specific ER stress in brains. Using Caenorhabditis elegans as a system to model ER stress, we generated transgenic nematodes overexpressing either wild-type or mutant human SOD1 to evaluate their relative impact on ER stress induction in vivo. These studies revealed a mutant-SOD1-specific increase in ER stress that was further exacerbated by changes in temperature, all of which was robustly attenuated by co-expression of torsinA. Moreover, through complementary behavioral analysis, torsinA was able to restore normal neuronal function in mutant G85R SOD1 animals. Furthermore, torsinA targeted mutant SOD1 for degradation via the proteasome, representing mechanistic insight on the activity that torsinA has on aggregate-prone proteins. These results expand our understanding of proteostatic mechanisms influencing neuronal dysfunction in ALS, while simultaneously highlighting the potential for torsinA as a novel target for therapeutic development.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Caenorhabditis elegans/fisiologia , Estresse do Retículo Endoplasmático , Chaperonas Moleculares/metabolismo , Atividade Motora , Animais , Animais Geneticamente Modificados , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Proteínas de Fluorescência Verde/metabolismo , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Superóxido Dismutase/genética , Sinapses/metabolismo , Sinapses/patologia , Transmissão Sináptica
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