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1.
Brain Behav Immun ; 111: 352-364, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37150266

RESUMEN

Alzheimer's dementia (AD) is a major contributor to global disability, and effective therapies to modify disease progression are currently lacking. The neuro-inflammatory theory is a potential etiology underlying this neurodegenerative disease. Previous randomized, controlled trials (RCTs) have provided inconclusive results regarding efficacy of omega-3 polyunsaturated fatty acids (PUFAs) regimens, which might provide anti-inflammatory benefits in the management of AD, in improving cognitive function among participants with AD. The objective of this frequentist-model based network meta-analysis (NMA) was to evaluate the potential advantages of omega-3 PUFAs and currently FDA-approved medications for AD on overall cognitive function in AD individuals. The primary outcomes were: (1) changes in cognitive function, and (2) acceptability, which refers to all-cause discontinuation. Additionally, secondary outcomes included quality of life, behavioral disturbances and safety/tolerability, which was assessed through the frequency of any reported adverse event. This NMA included 52 RCTs (6 with omega-3 PUFAs and 46 with FDA-approved medications) involving 21,111 participants. The results showed that long-term high-dose (1500-2000 mg/day) of eicosapentaenoic acid (EPA)-dominant omega-3 PUFAs augmented with anti-oxidants had the highest potential for cognitive improvement among all investigated treatments [standardized mean difference = 3.00, 95% confidence intervals (95 %CIs) = 1.84-4.16]. Compared to placebo, omega-3 PUFAs had similar acceptability [odds ratio (OR) = 0.46, 95 %CIs = 0.04 to 5.87] and safety profiles (OR = 1.24, 95 %CIs = 0.66 to 2.33)o. These findings support the potential neurotherapeutic effects of high dosage EPA-dominant omega-3 PUFAs for the amelioration of cognitive decline in patients with AD. Future large-scale, long-term RCTs should focus on different dosages of EPA-dominant omega-3 PUFAs regimens on improving cognitive dysfunction in patients with AD at different levels of inflammatory status and psychopathology.


Asunto(s)
Enfermedad de Alzheimer , Ácidos Grasos Omega-3 , Humanos , Ácido Eicosapentaenoico/farmacología , Ácido Eicosapentaenoico/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Metaanálisis en Red , Ácidos Grasos Omega-3/uso terapéutico , Cognición , Antiinflamatorios/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Psychiatry Clin Neurosci ; 77(11): 592-596, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37612880

RESUMEN

ChatGPT has sparked extensive discussions within the healthcare community since its November 2022 release. However, potential applications in the field of psychiatry have received limited attention. Deep learning has proven beneficial to psychiatry, and GPT is a powerful deep learning-based language model with immense potential for this field. Despite the convenience of ChatGPT, this advanced chatbot currently has limited practical applications in psychiatry. It may be used to support psychiatrists in routine tasks such as completing medical records, facilitating communications between clinicians and with patients, polishing academic writings and presentations, and programming and performing analyses for research. The current training and application of ChatGPT require using appropriate prompts to maximize appropriate outputs and minimize deleterious inaccuracies and phantom errors. Moreover, future GPT advances that incorporate empathy, emotion recognition, personality assessment, and detection of mental health warning signs are essential for its effective integration into psychiatric care. In the near future, developing a fully-automated psychotherapy system trained for expert communication (such as psychotherapy verbatim) is conceivable by building on foundational GPT technology. This dream system should integrate practical 'real world' inputs and friendly AI user and patient interfaces via clinically validated algorithms, voice comprehension/generation modules, and emotion discrimination algorithms based on facial expressions and physiological inputs from wearable devices. In addition to the technology challenges, we believe it is critical to establish generally accepted ethical standards for applying ChatGPT-related tools in all mental healthcare environments, including telemedicine and academic/training settings.


Asunto(s)
Psiquiatría , Humanos , Algoritmos , Emociones , Empatía , Lenguaje
3.
Ann Surg ; 269(1): 66-72, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29958227

RESUMEN

OBJECTIVE: Surgeon-scientists are an essential component of the field of academic surgery, contributing to the fundamental understanding of disease and the discovery of innovative therapies. Despite this recognized value, the current landscape of academic medicine presents significant barriers to establishing and maintaining a successful career as a surgeon performing basic/translational research. Our objective is to define these barriers to academic success for surgeons, and to provide a consensus strategy for optimizing the chances of success. SUMMARY BACKGROUND DATA: There is a significant decline in the proportion of academic surgeons who are pursuing basic science/translational research, which represents a potential threat to the very identify of the translational surgeon-scientist. METHODS: Based on published literature and expert opinion, the Basic Science Committee of the Society of University of Surgeons prepared this roadmap to encourage and guide the next generation of surgeon-scientists as they embark on their academic careers. RESULTS: This roadmap highlights key elements to consider in choosing an initial job and the importance of identifying a team of committed mentors. Expectations and guidelines for the first several years in practice are offered. CONCLUSIONS: With guidance and mentorship, aspiring surgeonscientists can overcome the challenges inherent in choosing this career path and sustain the important legacy of those before them.


Asunto(s)
Investigación Biomédica/educación , Selección de Profesión , Educación de Postgrado en Medicina/métodos , Cirugía General/educación , Mentores , Cirujanos/educación , Investigación Biomédica Traslacional/educación , Humanos
4.
Mol Pharm ; 16(8): 3350-3360, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31082240

RESUMEN

Alkylphosphocholine (APC) analogs are a novel class of broad-spectrum tumor-targeting agents that can be used for both diagnosis and treatment of cancer. The potential for clinical translation for APC analogs will strongly depend on their pharmacokinetic (PK) profiles. The aim of this work was to understand how the chemical structures of various APC analogs impact binding and PK. To achieve this aim, we performed in silico docking analysis, in vitro and in vivo partitioning experiments, and in vivo PK studies. Our results have identified 7 potential high-affinity binding sites of these compounds on human serum albumin (HSA) and suggest that the size of the functional group directly influences the albumin binding, partitioning, and PK. Namely, the bulkier the functional groups, the weaker the agent binds to albumin, the more the agent partitions onto lipoproteins, and the less time the agent spends in circulation. The results of these experiments provide novel molecular insights into the binding, partitioning, and PK of this class of compounds and similar molecules as well as suggest pharmacological strategies to alter their PK profiles. Importantly, our methodology may provide a way to design better drugs by better characterizing the PK profile for lead compound optimization.


Asunto(s)
Antineoplásicos/farmacocinética , Diseño de Fármacos , Simulación del Acoplamiento Molecular , Fosforilcolina/farmacocinética , Albúmina Sérica Humana/metabolismo , Animales , Antineoplásicos/química , Humanos , Lipoproteínas/metabolismo , Ratones , Ratones Desnudos , Modelos Biológicos , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Fosforilcolina/análogos & derivados , Fosforilcolina/química
5.
Ann Surg ; 265(6): 1053-1059, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27643928

RESUMEN

OBJECTIVE: The aim of this study was to examine the challenges confronting surgeons performing basic science research in today's academic surgery environment. SUMMARY OF BACKGROUND DATA: Multiple studies have identified challenges confronting surgeon-scientists and impacting their ability to be successful. Although these threats have been known for decades, the downward trend in the number of successful surgeon-scientists continues. Clinical demands, funding challenges, and other factors play important roles, but a rigorous analysis of academic surgeons and their experiences regarding these issues has not previously been performed. METHODS: An online survey was distributed to 2504 members of the Association for Academic Surgery and Society of University Surgeons to determine factors impacting success. Survey results were subjected to statistical analyses. We also reviewed publicly available data regarding funding from the National Institutes of Health (NIH). RESULTS: NIH data revealed a 27% decline in the proportion of NIH funding to surgical departments relative to total NIH funding from 2007 to 2014. A total of 1033 (41%) members responded to our survey, making this the largest survey of academic surgeons to date. Surgeons most often cited the following factors as major impediments to pursuing basic investigation: pressure to be clinically productive, excessive administrative responsibilities, difficulty obtaining extramural funding, and desire for work-life balance. Surprisingly, a majority (68%) did not believe surgeons can be successful basic scientists in today's environment, including departmental leadership. CONCLUSIONS: We have identified important barriers that confront academic surgeons pursuing basic research and a perception that success in basic science may no longer be achievable. These barriers need to be addressed to ensure the continued development of future surgeon-scientists.


Asunto(s)
Investigación Biomédica/tendencias , Cirujanos/tendencias , Investigación Biomédica/economía , Financiación Gubernamental , Predicción , Humanos , National Institutes of Health (U.S.) , Cirujanos/educación , Estados Unidos
6.
J Exp Bot ; 68(14): 3773-3784, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28911056

RESUMEN

Seagrasses are unique angiosperms that carry out growth and reproduction submerged in seawater. They occur in at least three families of the Alismatales. All have chloroplasts mainly in the cells of the epidermis. Living in seawater, the supply of inorganic carbon (Ci) to the chloroplasts is diffusion limited, especially under unstirred conditions. Therefore, the supply of CO2 and bicarbonate across the diffusive boundary layer on the outer side of the epidermis is often a limiting factor. Here we discuss the evidence for mechanisms that enhance the uptake of Ci into the epidermal cells. Since bicarbonate is plentiful in seawater, a bicarbonate pump might be expected; however, the evidence for such a pump is not strongly supported. There is evidence for a carbonic anhydrase outside the outer plasmalemma. This, together with evidence for an outward proton pump, suggests the possibility that local acidification leads to enhanced concentrations of CO2 adjacent to the outer tangential epidermal walls, which enhances the uptake of CO2, and this could be followed by a carbon-concentrating mechanism (CCM) in the cytoplasm and/or chloroplasts. The lines of evidence for such an epidermal CCM are discussed, including evidence for special 'transfer cells' in some but not all seagrass leaves in the tangential inner walls of the epidermal cells. It is concluded that seagrasses have a CCM but that the case for concentration of CO2 at the site of Rubisco carboxylation is not proven.


Asunto(s)
Alismatales/metabolismo , Compuestos Inorgánicos de Carbono/metabolismo , Fotosíntesis , Epidermis de la Planta/metabolismo , Alismatales/enzimología , Bicarbonatos/metabolismo , Anhidrasas Carbónicas/metabolismo
7.
Carcinogenesis ; 37(9): 839-851, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27287871

RESUMEN

Microglia play important roles in extracellular matrix remodeling, tumor invasion, angiogenesis, and suppression of adaptive immunity in glioma. Na(+)/H(+) exchanger isoform 1 (NHE1) regulates microglial activation and migration. However, little is known about the roles of NHE1 in intratumoral microglial activation and microglia-glioma interactions. Our study revealed up-regulation of NHE1 protein expression in both glioma cells and tumor-associated Iba1(+) microglia in glioma xenografts and glioblastoma multiforme microarrays. Moreover, we observed positive correlation of NHE1 expression with Iba1 intensity in microglia/macrophages. Glioma cells, via conditioned medium or non-contact glioma-microglia co-cultures, concurrently upregulated microglial expression of NHE1 protein and other microglial activation markers (iNOS, arginase-1, TGF-ß, IL-6, IL-10 and the matrix metalloproteinases MT1-MMP and MMP9). Interestingly, glioma-stimulated microglia reciprocally enhanced glioma proliferation and migration. Most importantly, inhibition of microglial NHE1 activity via small interfering RNA (siRNA) knockdown or the potent NHE1-specific inhibitor HOE642 significantly attenuated microglial activation and abolished microglia-stimulated glioma migration and proliferation. Taken together, our findings provide the first evidence that NHE1 function plays an important role in glioma-microglia interactions, enhancing glioma proliferation and invasion by stimulating microglial release of soluble factors. NHE1 upregulation is a novel marker of the glioma-associated microglial activation phenotype. Inhibition of NHE1 represents a novel glioma therapeutic strategy by targeting tumor-induced microglial activation.


Asunto(s)
Neoplasias Encefálicas/patología , Proteínas de Transporte de Catión/fisiología , Glioma/patología , Microglía/fisiología , Intercambiadores de Sodio-Hidrógeno/fisiología , Proteínas de Unión al Calcio , Proteínas de Transporte de Catión/análisis , Línea Celular Tumoral , Movimiento Celular , Polaridad Celular , Proliferación Celular , Proteínas de Unión al ADN/análisis , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas de Microfilamentos , Invasividad Neoplásica , Intercambiador 1 de Sodio-Hidrógeno , Intercambiadores de Sodio-Hidrógeno/análisis
8.
Radiology ; 281(1): 99-108, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27192459

RESUMEN

Purpose To demonstrate that magnetic resonance (MR) imaging-monitored transcranial focused ultrasound can enhance the delivery of the antiangiogenic monoclonal antibody bevacizumab into the central nervous system (CNS) for glioblastoma multiforme (GBM) treatment. Materials and Methods All animal experiments were approved by the animal committee and adhered to experimental animal care guidelines. Transcranial focused ultrasound exposure in the presence of microbubbles was used to open the blood-brain barrier (BBB) to enhance bevacizumab penetration into the CNS in healthy and glioma-bearing mice. Bevacizumab concentration was quantitated with high-performance liquid chromatography, and Western blot testing was performed to confirm the specific biologic form in the CNS. Penetration of bevacizumab into brain tissue was estimated in vivo by means of contrast material-enhanced MR imaging and quantitative gallium 68 ((68)Ga)-bevacizumab micro-positron emission tomography, and glioma progression was longitudinally followed with T2-weighted MR imaging. Hematoxylin-eosin staining and cluster of differentiation 31 immunostaining were used to assess morphologic changes and vascular inhibition at histologic examination. The two-tailed Student t test and the Mantel-Cox log-rank test were used for statistical analyses, with a significance level of .05. Results Focused ultrasound significantly enhanced bevacizumab penetration into the CNS by 5.7- to 56.7-fold compared with that in nonexposed brain (both P < .0001). Contrast-enhanced MR imaging indexes correlated with bevacizumab concentration (r = 0.748-0.857) in vivo. Focused ultrasound-enhanced bevacizumab delivery significantly retarded glioma progression, with a significantly increased median survival (median increase in survival time = 135% in the group treated with bevacizumab and focused ultrasound, P < .0001; as compared with 48% in the group treated with bevacizumab alone, P = .0002). Conclusion Focused ultrasound-enhanced bevacizumab delivery can provide an antivascularization normalization effect to suppress glioma. (©) RSNA, 2016 Online supplemental material is available for this article.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Barrera Hematoencefálica , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Terapia por Ultrasonido/métodos , Animales , Western Blotting , Neoplasias Encefálicas/diagnóstico por imagen , Cromatografía Líquida de Alta Presión , Medios de Contraste , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Gadolinio DTPA , Glioma/diagnóstico por imagen , Estudios Longitudinales , Imagen por Resonancia Magnética , Ratones , Microburbujas , Tomografía de Emisión de Positrones , Resultado del Tratamiento
9.
Mol Pharm ; 13(9): 3341-9, 2016 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-27421304

RESUMEN

Cancer-targeting alkylphosphocholine (APC) analogues are being clinically developed for diagnostic imaging, intraoperative visualization, and therapeutic applications. These APC analogues derived from chemically synthesized phospholipid ethers were identified and optimized for cancer-targeting specificity using extensive structure-activity studies. While they strongly label human brain cancers associated with disrupted blood-brain barriers (BBB), APC permeability across intact BBB remains unknown. Three of our APC analogues, CLR1404 (PET radiotracer), CLR1501 (green fluorescence), and CLR1502 (near-infrared fluorescence), were tested for permeability across a BBB model composed of human induced pluripotent stem cell-derived brain microvascular endothelial cells (iPSC-derived BMECs). This in vitro BBB system has reproducibly consistent high barrier integrity marked by high transendothelial electrical resistance (TEER > 1500 Ω-cm(2)) and functional expression of drug efflux transporters. The radioiodinated and fluorescent APC analogues demonstrated fairly low permeability across the iPSC-BMEC (35 ± 5.7 (CLR1404), 54 ± 3.2 (CLR1501), and 26 ± 4.9 (CLR1502) × 10(-5) cm/min) compared with BBB-impermeable sucrose (13 ± 2.5) and BBB-permeable diazepam (170 ± 29). Only the fluorescent APC analogues (CLR1501, CLR1502) underwent BCRP and MRP polarized drug efflux transport in the brain-to-blood direction of the BBB model, and this efflux can be specifically blocked with pharmacological inhibition. None of the tested APC analogues appeared to undergo substantial P-gp transport. Limited permeability of the APC analogues across an intact BBB into normal brain likely contributes to the high tumor to background ratios observed in initial human trials. Moreover, addition of fluorescent moieties to APCs resulted in greater BMEC efflux via MRP and BCRP, and may affect fluorescence-guided applications. Overall, the characterization of APC analogue permeability across human BBB is significant for advancing future brain tumor-targeted applications of these agents.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Fosforilcolina/análogos & derivados , Antineoplásicos/metabolismo , Diferenciación Celular/fisiología , Células Cultivadas , Humanos , Inmunohistoquímica , Células Madre Pluripotentes Inducidas/citología
10.
Br J Neurosurg ; 30(4): 448-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26760290

RESUMEN

CT images of an 18-year-old woman who had sustained head trauma after a motor vehicle accident are presented demonstrating the iatrogenic intracranial placement of a nasopharyngeal airway. Treatment required a decompressive craniectomy, removal of the nasopharyngeal airway under direct vision, and duraplasty. The patient made a good neurological recovery, but did require ongoing medical treatment for diabetes insipidus. The case illustrates the importance of avoiding intranasal placement of any object in a patient with head trauma and suspected skull base fractures prior to diagnostic imaging.


Asunto(s)
Lesiones Encefálicas/cirugía , Craniectomía Descompresiva , Presión Intracraneal/fisiología , Base del Cráneo/cirugía , Accidentes de Tránsito , Adolescente , Lesiones Encefálicas/diagnóstico , Craniectomía Descompresiva/métodos , Femenino , Humanos , Enfermedad Iatrogénica/prevención & control , Resultado del Tratamiento
12.
Am J Bot ; 102(2): 290-301, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25667081

RESUMEN

PREMISE OF THE STUDY: Few studies have investigated the effects of substrates on the accumulation and precipitation of magnesium, calcium, and sulfur in plants. Acacia stipuligera and A. robeorum growing in their natural habitats with different substrates show different accumulation and precipitation patterns of these elements. Here, we compared the accumulation and precipitation of magnesium, calcium, and sulfur in A. stipuligera and A. robeorum grown in different substrates proposed for mine-site rehabilitation and expected the differences in substrates to have significant effects on the accumulation and precipitation of these elements in the two species. METHODS: Saplings were grown in sandy topsoil or in a topsoil-siltstone mixture in a glasshouse. Phyllode magnesium, calcium, and sulfur concentrations of 25-wk-old plants were measured. Precipitation of these elements in phyllodes and branchlets was investigated by means of scanning electron microscopy and energy-dispersive x-ray spectroscopy. KEY RESULTS: Phyllode magnesium, calcium, and sulfur concentrations were generally significantly greater in A. robeorum than in A. stipuligera. The two species responded in unique ways to the substrate, with A. stipuligera having similar phyllode magnesium and calcium concentrations in both substrates, but greater sulfur concentration in the topsoil-siltstone mixture, while A. robeorum showed lower phyllode magnesium, calcium, and sulfur concentrations in the topsoil-siltstone mixture. For both substrates, mineral precipitates were observed in both species, with A. robeorum having more mineral precipitates containing magnesium, calcium, and sulfur in its phyllodes than A. stipuligera did. CONCLUSIONS: The accumulation and precipitation patterns of magnesium, calcium, and sulfur are more species-specific than substrate-affected.


Asunto(s)
Acacia/metabolismo , Calcio/metabolismo , Magnesio/metabolismo , Minerales/metabolismo , Tallos de la Planta/metabolismo , Suelo/química , Azufre/metabolismo , Acacia/clasificación , Biodegradación Ambiental , Ecosistema , Microscopía Electrónica de Rastreo , Minería , Especificidad de la Especie
13.
Carcinogenesis ; 35(9): 2014-24, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24717311

RESUMEN

Sodium-hydrogen exchanger isoform 1 (NHE1) plays a role in survival and migration/invasion of several cancers and is an emerging new therapeutic target. However, the role of NHE1 in glioblastoma and the interaction of NHE1 expression and function in glioblastoma cells with cytotoxic temozolomide (TMZ) therapy remain unknown. In this study, we detected high levels of NHE1 protein only in primary human glioma cells (GC), glioma xenografts and glioblastoma, but not in human neural stem cells or astrocytes. GC exhibited an alkaline resting pHi (7.46±0.04) maintained by robust NHE1-mediated H(+) extrusion. GC treatment with TMZ for 2-24h triggered a transient decrease in pHi, which recovered by 48h and correlated with concurrent upregulation of NHE1 protein expression. NHE1 protein was colocalized with ezrin at lamellipodia and probably involved in GC migration. The TMZ-treated GC exhibited increased migration and invasion, which was attenuated by addition of NHE1 inhibitor HOE-642. Most importantly, NHE1 inhibition prevented prosurvival extracellular signal-regulated kinase activation and accelerated TMZ-induced apoptosis. Taken together, our study provides the first evidence that GC upregulate NHE1 protein to maintain alkaline pHi. Combining TMZ therapy with NHE1 inhibition suppresses GC migration and invasion, and also augments TMZ-induced apoptosis. These findings strongly suggest that NHE1 is an important cytoprotective mechanism in GC and presents a new therapeutic strategy of combining NHE1 inhibition and TMZ chemotherapy.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Proteínas de Transporte de Catión/genética , Movimiento Celular , Supervivencia Celular , Dacarbazina/análogos & derivados , Resistencia a Antineoplásicos , Intercambiadores de Sodio-Hidrógeno/genética , Equilibrio Ácido-Base , Animales , Apoptosis , Astrocitos/metabolismo , Transporte Biológico , Proteínas de Transporte de Catión/metabolismo , Línea Celular Tumoral , Dacarbazina/farmacología , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Células-Madre Neurales/metabolismo , Intercambiador 1 de Sodio-Hidrógeno , Intercambiadores de Sodio-Hidrógeno/metabolismo , Temozolomida , Regulación hacia Arriba
14.
Mol Cancer ; 13: 31, 2014 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-24555568

RESUMEN

BACKGROUND: The bumetanide (BMT)-sensitive Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) maintains cell volume homeostasis by increasing intracellular K+ and Cl- content via regulatory volume increase (RVI). Expression levels of NKCC1 positively correlate with the histological grade and severity of gliomas, the most common primary adult brain tumors, and up-regulated NKCC1 activity facilitates glioma cell migration and apoptotic resistance to the chemotherapeutic drug temozolomide (TMZ). However, the cellular mechanisms underlying NKCC1 functional up-regulation in glioma and in response to TMZ administration remain unknown. METHODS: Expression of NKCC1 and its upstream kinases With-No-K (Lysine) kinase 1 (WNK1) and oxidative stress-responsive kinase-1 (OSR1) in different human glioma cell lines and glioma specimens were detected by western blotting and immunostaining. Live cell imaging and microchemotaxis assay were applied to record glioma cell movements under different treatment conditions. Fluorescence indicators were utilized to measure cell volume, intracellular K+ and Cl- content to reflect the activity of NKCC1 on ion transportation. Small interfering RNA (siRNA)-mediated knockdown of WNK1 or OSR1 was used to explore their roles in regulation of NKCC1 activity in glioma cells. Results of different treatment groups were compared by one-way ANOVA using the Bonferroni post-hoc test in the case of multiple comparisons. RESULTS: We show that compared to human neural stem cells and astrocytes, human glioma cells exhibit robust increases in the activation and phosphorylation of NKCC1 and its two upstream regulatory kinases, WNK1 and OSR1. siRNA-mediated knockdown of WNK1 or OSR1 reduces intracellular K+ and Cl- content and RVI in glioma cells by abolishing NKCC1 regulatory phospho-activation. Unexpectedly, TMZ activates the WNK1/OSR1/NKCC1 signaling pathway and enhances glioma migration. Pharmacological inhibition of NKCC1 with its potent inhibitor BMT or siRNA knockdown of WNK1 or OSR1 significantly decreases glioma cell migration after TMZ treatment. CONCLUSION: Together, our data show a novel role for the WNK1/OSR1/NKCC1 pathway in basal and TMZ-induced glioma migration, and suggest that glioma treatment with TMZ might be improved by drugs that inhibit elements of the WNK1/OSR1/NKCC1 signaling pathway.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Movimiento Celular , Glioma/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Western Blotting , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Glioma/patología , Humanos , Inmunohistoquímica , Antígenos de Histocompatibilidad Menor , Análisis de Matrices Tisulares , Proteína Quinasa Deficiente en Lisina WNK 1
15.
Plant Cell Environ ; 37(6): 1276-98, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24895754

RESUMEN

Proteaceae species in south-western Australia occur on phosphorus- (P) impoverished soils. Their leaves contain very low P levels, but have relatively high rates of photosynthesis. We measured ribosomal RNA (rRNA) abundance, soluble protein, activities of several enzymes and glucose 6-phosphate (Glc6P) levels in expanding and mature leaves of six Proteaceae species in their natural habitat. The results were compared with those for Arabidopsis thaliana. Compared with A. thaliana, immature leaves of Proteaceae species contained very low levels of rRNA, especially plastidic rRNA. Proteaceae species showed slow development of the photosynthetic apparatus ('delayed greening'), with young leaves having very low levels of chlorophyll and Calvin-Benson cycle enzymes. In mature leaves, soluble protein and Calvin-Benson cycle enzyme activities were low, but Glc6P levels were similar to those in A. thaliana. We propose that low ribosome abundance contributes to the high P efficiency of these Proteaceae species in three ways: (1) less P is invested in ribosomes; (2) the rate of growth and, hence, demand for P is low; and (3) the especially low plastidic ribosome abundance in young leaves delays formation of the photosynthetic machinery, spreading investment of P in rRNA. Although Calvin-Benson cycle enzyme activities are low, Glc6P levels are maintained, allowing their effective use.


Asunto(s)
Fósforo/metabolismo , Proteaceae/fisiología , ARN de Planta/metabolismo , ARN Ribosómico/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiología , Clorofila/metabolismo , Glucosa-6-Fosfato/metabolismo , Fotosíntesis , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteaceae/genética , Proteaceae/metabolismo , Proteínas Ribosómicas/metabolismo , Almidón/metabolismo
16.
J Neurooncol ; 116(1): 187-93, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24142200

RESUMEN

UNLABELLED: The pupose of this study is to assess the long-term outcome and toxicity of fractionated stereotactic radiation therapy (FSRT) and stereotactic radiosurgery (SRS) for 100 vestibular schwannomas treated at a single institution. From 1993 to 2007, 104 patients underwent were treated with radiation therapy for vestibular schwannoma. Forty-eight patients received SRS, with a median prescription dose of 12.5 Gy for SRS (range 9.7-16 Gy). For FSRT, two different fraction schedules were employed: a conventional schedule (ConFSRT) of 1.8 Gy per fraction (Gy/F) for 25 or 28 fractions to a total dose of 45 or 50.4 Gy (n = 19); and a once weekly hypofractionated course (HypoFSRT) consisting of 4 Gy/F for 5 fractions to a total dose of 20 Gy (n = 37). Patients treated with FSRT had better baseline hearing, facial, and trigeminal nerve function, and were more likely to have a diagnosis of NF2. The 5-year progression free rate (PFR) was 97.0 after SRS, 90.5% after HypoFSRT, and 100.0% after ConFSRT (p = NS). Univariate analysis demonstrated that NF2 and larger tumor size (greater than the median) correlated with poorer local control, but prior surgical resection did not. Serviceable hearing was preserved in 60.0% of SRS patients, 63.2% of HypoFSRT patients, and 44.4% of ConFSRT patients (p = 0.6). Similarly, there were no significant differences in 5-year rates of trigeminal toxicity facial nerve toxicity, vestibular dysfunction, or tinnitus. CONCLUSIONS: Equivalent 5-year PFR and toxicity rates are shown for patients with vestibular schwanoma selected for SRS, HypoFSRT, and ConFSRT after multidisciplinary evaluation. Factors correlating with tumor progression included NF2 and larger tumor size.


Asunto(s)
Neuroma Acústico/cirugía , Radiocirugia , Radioterapia Asistida por Computador , Estudios de Cohortes , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Nervio Facial/patología , Femenino , Trastornos de la Audición/etiología , Humanos , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Neuroma Acústico/complicaciones , Neuroma Acústico/mortalidad , Acúfeno/etiología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Nervio Trigémino/patología
17.
Adv Nutr ; 15(2): 100163, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38110000

RESUMEN

Migraine is a highly prevalent neurologic disorder with prevalence rates ranging from 9% to 18% worldwide. Current pharmacologic prophylactic strategies for migraine have limited efficacy and acceptability, with relatively low response rates of 40% to 50% and limited safety profiles. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are considered promising therapeutic agents for migraine prophylaxis. The aim of this network meta-analysis (NMA) was to compare the efficacy and acceptability of various dosages of EPA/DHA and other current Food and Drug Administration-approved or guideline-recommended prophylactic pharmacologic interventions for migraine. Randomized controlled trials (RCTs) were eligible for inclusion if they enrolled participants with a diagnosis of either episodic or chronic migraine. All NMA procedures were conducted under the frequentist model. The primary outcomes assessed were 1) changes in migraine frequency and 2) acceptability (i.e., dropout for any reason). Secondary outcomes included response rates, changes in migraine severity, changes in the frequency of using rescue medications, and frequency of any adverse events. Forty RCTs were included (N = 6616; mean age = 35.0 y; 78.9% women). Our analysis showed that supplementation with high dosage EPA/DHA yields the highest decrease in migraine frequency [standardized mean difference (SMD): -1.36; 95% confidence interval (CI): -2.32, -0.39 compared with placebo] and the largest decrease in migraine severity (SMD: -2.23; 95% CI: -3.17, -1.30 compared with placebo) in all studied interventions. Furthermore, supplementation with high dosage EPA/DHA showed the most favorable acceptability rates (odds ratio: 1.00; 95% CI: 0.06, 17.41 compared with placebo) of all examined prophylactic treatments. This study provides compelling evidence that high dosage EPA/DHA supplementation can be considered a first-choice treatment of migraine prophylaxis because this treatment displayed the highest efficacy and highest acceptability of all studied treatments. This study was registered in PROSPERO as CRD42022319577.


Asunto(s)
Ácidos Grasos Omega-3 , Trastornos Migrañosos , Femenino , Humanos , Adulto , Masculino , Ácidos Grasos Omega-3/uso terapéutico , Metaanálisis en Red , Ácidos Docosahexaenoicos , Ácido Eicosapentaenoico/uso terapéutico , Trastornos Migrañosos/prevención & control , Trastornos Migrañosos/inducido químicamente , Trastornos Migrañosos/tratamiento farmacológico , Suplementos Dietéticos
18.
J Virol ; 86(2): 854-64, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22090104

RESUMEN

Viruses are appreciated as etiological agents of certain human tumors, but the number of different cancer types induced or exacerbated by viral infections is unknown. Glioblastoma multiforme (GBM)/astrocytoma grade IV is a malignant and lethal brain cancer of unknown origin. Over the past decade, several studies have searched for the presence of a prominent herpesvirus, human cytomegalovirus (HCMV), in GBM samples. While some have detected HCMV DNA, RNA, and proteins in GBM tissues, others have not. Therefore, any purported association of HCMV with GBM remains controversial. In most of the previous studies, only one or a select few viral targets were analyzed. Thus, it remains unclear the extent to which the entire viral genome was present when detected. Here we report the results of a survey of GBM specimens for as many as 20 different regions of the HCMV genome. Our findings indicate that multiple HCMV loci are statistically more likely to be found in GBM samples than in other brain tumors or epileptic brain specimens and that the viral genome was more often detected in frozen samples than in paraffin-embedded archival tissue samples. Finally, our experimental results indicate that cellular genomes substantially outnumber viral genomes in HCMV-positive GBM specimens, likely indicating that only a minority of the cells found in such samples harbor viral DNA. These data argue for the association of HCMV with GBM, defining the virus as oncoaccessory. Furthermore, they imply that, were HCMV to enhance the growth or survival of a tumor (i.e., if it is oncomodulatory), it would likely do so through mechanisms distinct from classic tumor viruses that express transforming viral oncoproteins in the overwhelming majority of tumor cells.


Asunto(s)
Neoplasias Encefálicas/virología , Infecciones por Citomegalovirus/virología , Citomegalovirus/genética , Citomegalovirus/aislamiento & purificación , Genoma Viral , Glioblastoma/virología , Neoplasias Encefálicas/patología , Infecciones por Citomegalovirus/patología , ADN Viral/genética , Glioblastoma/patología , Humanos , Estudios Retrospectivos
19.
Neurosurg Focus ; 34(4): E7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23544413

RESUMEN

OBJECT: Functional MRI (fMRI) is commonly used by neurosurgeons preoperatively to identify brain regions associated with essential behaviors, such as language and motor abilities. In this study the authors investigated the relationship between patient morbidity and mortality and the distance from the tumor border area to functional activations in secondary motor and language cortices. METHODS: Patients with primary or metastatic brain tumors who underwent preoperative fMRI motor and language mapping were selected from a large database of patients with tumors. The lesion-to-activation distance (LAD) was measured in each patient relative to the supplementary motor area (SMA) for motor tasks and the presupplementary motor area (pSMA) for language tasks. The association between LAD and the incidence of deficits was investigated using the Fisher exact tests of significance. The impact of other variables, including age, handedness, sex, and tumor grade, was also investigated. In a subset of patients, logistic regression was performed to identify the likelihood of deficits based on the LAD to primary and secondary regions. Finally, Mantel-Cox log-rank tests were performed to determine whether survival time was significantly related to the LAD to secondary motor and language areas. RESULTS: A significant association was observed between the LAD to the SMA and the incidence of motor deficits, with the percentage of patients with deficits dropping for those in the LAD > 2 cm group. The relationship between the LAD to the pSMA and the incidence of language deficits was not significant. Logistic regression demonstrated that the LAD to primary sensorimotor cortex does affect the incidence of motor deficits, but that the LAD to SMA does not. Finally, the authors observed no relationship between the LAD to secondary regions and patient mortality rates. CONCLUSIONS: These results demonstrate that the LAD to SMA structures does affect morbidity, although not to the extent of LAD to primary structures. In addition, motor deficits are significantly associated with LAD to secondary structures, but language deficits are not. This should be considered by neurosurgeons for patient consultation and preoperative planning.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidad , Lóbulo Frontal/fisiología , Lenguaje , Imagen por Resonancia Magnética/métodos , Corteza Motora/fisiología , Lóbulo Temporal/fisiología , Adulto , Mapeo Encefálico/métodos , Neoplasias Encefálicas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Cuidados Preoperatorios/métodos , Estudios Retrospectivos
20.
Neurosurg Focus ; 34(4): E6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23544412

RESUMEN

OBJECT: Functional MRI (fMRI) has the potential to be a useful presurgical planning tool to treat patients with primary brain tumor. In this study the authors retrospectively explored relationships between language-related postoperative outcomes in such patients and multiple factors, including measures estimated from task fMRI maps (proximity of lesion to functional activation area, or lesion-to-activation distance [LAD], and activation-based language lateralization, or lateralization index [LI]) used in the clinical setting for presurgical planning, as well as other factors such as patient age, patient sex, tumor grade, and tumor volume. METHODS: Patient information was drawn from a database of patients with brain tumors who had undergone preoperative fMRI-based language mapping of the Broca and Wernicke areas. Patients had performed a battery of tasks, including word-generation tasks and a text-versus-symbols reading task, as part of a clinical fMRI protocol. Individually thresholded task fMRI activation maps had been provided for use in the clinical setting. These clinical imaging maps were used to retrospectively estimate LAD and LI for the Broca and Wernicke areas. RESULTS: There was a relationship between postoperative language deficits and the proximity between tumor and Broca area activation (the LAD estimate), where shorter LADs were related to the presence of postoperative aphasia. Stratification by tumor location further showed that for posterior tumors within the temporal and parietal lobes, more bilaterally oriented Broca area activation (LI estimate close to 0) and a shorter Wernicke area LAD were associated with increased postoperative aphasia. Furthermore, decreasing LAD was related to decreasing LI for both Broca and Wernicke areas. Preoperative deficits were related to increasing patient age and a shorter Wernicke area LAD. CONCLUSIONS: Overall, LAD and LI, as determined using fMRI in the context of these paradigms, may be useful indicators of postsurgical outcomes. Whereas tumor location may influence postoperative deficits, the results indicated that tumor proximity to an activation area might also interact with how the language network is affected as a whole by the lesion. Although the derivation of LI must be further validated in individual patients by using spatially specific statistical methods, the current results indicated that fMRI is a useful tool for predicting postoperative outcomes in patients with a single brain tumor.


Asunto(s)
Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/cirugía , Lóbulo Frontal/cirugía , Lenguaje , Imagen por Resonancia Magnética/métodos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Mapeo Encefálico/métodos , Neoplasias Encefálicas/diagnóstico , Bases de Datos Factuales/tendencias , Femenino , Lóbulo Frontal/fisiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Habla/fisiología , Resultado del Tratamiento , Adulto Joven
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