Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
J Imaging ; 9(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37888302

RESUMO

In the organizing of professional training, the assessment of the trainee's reaction and state in stressful situations is of great importance. Phobic reactions are a specific type of stress reaction that, however, is rarely taken into account when developing virtual simulators, and are a risk factor in the workplace. A method for evaluating the impact of various phobic stimuli on the quality of training is considered, which takes into account the time, accuracy, and speed of performing professional tasks, as well as the characteristics of electroencephalograms (the amplitude, power, coherence, Hurst exponent, and degree of interhemispheric asymmetry). To evaluate the impact of phobias during experimental research, participants in the experimental group performed exercises in different environments: under normal conditions and under the influence of acrophobic and arachnophobic stimuli. The participants were divided into subgroups using clustering algorithms and an expert neurologist. After that, a comparison of the subgroup metrics was carried out. The research conducted makes it possible to partially confirm our hypotheses about the negative impact of phobic effects on some participants in the experimental group. The relationship between the reaction to a phobia and the characteristics of brain activity was revealed, and the characteristics of the electroencephalogram signal were considered as the metrics for detecting a phobic reaction.

2.
Sensors (Basel) ; 23(19)2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37836887

RESUMO

When patients perform musculoskeletal rehabilitation exercises, it is of great importance to observe the correctness of their performance. The aim of this study is to increase the accuracy of recognizing human movements during exercise. The process of monitoring and evaluating musculoskeletal rehabilitation exercises was modeled using various tracking systems, and the necessary algorithms for processing information for each of the tracking systems were formalized. An approach to classifying exercises using machine learning methods is presented. Experimental studies were conducted to identify the most accurate tracking systems (virtual reality trackers, motion capture, and computer vision). A comparison of machine learning models is carried out to solve the problem of classifying musculoskeletal rehabilitation exercises, and 96% accuracy is obtained when using multilayer dense neural networks. With the use of computer vision technologies and the processing of a full set of body points, the accuracy of classification achieved is 100%. The hypotheses on the ranking of tracking systems based on the accuracy of positioning of human target points, the presence of restrictions on application in the field of musculoskeletal rehabilitation, and the potential to classify exercises are fully confirmed.


Assuntos
Exercício Físico , Movimento , Humanos , Terapia por Exercício/métodos , Redes Neurais de Computação , Algoritmos
3.
J Pers Med ; 13(4)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37108980

RESUMO

Each individual has a unique and interacting set of genetic, lifestyle, and environmental factors that are reflected in their physical exam and laboratory biomarkers and significantly impact their experience of health. Patterns of nutrient deficiency signs and biomarker levels below health-promoting thresholds have been identified in national nutrition surveys. However, identifying these patterns remains a challenge in clinical medicine for many reasons, including clinician training and education, clinical time restraints, and the belief that these signs are both rare and recognizable only in cases of severe nutritional deficiencies. With an increased interest in prevention and limited resources for comprehensive diagnostic evaluations, a functional nutrition evaluation may augment patient-centered screening evaluations and personalized wellness programs. During LIFEHOUSE, we have documented physical exam, anthropometric, and biomarker findings that may increase the recognition of these wellness-challenging patterns in a population of 369 adult employees working in two occupational areas: administrative/sales and manufacturing/warehouse. Distinct and significant physical exam differences and constellations of biomarker abnormalities were identified. We present these patterns of physical exam findings, anthropometrics, and advanced biomarkers to assist clinicians in diagnostic and therapeutic interventions that may stem the loss of function that precedes the development of the non-communicable chronic diseases of aging.

4.
Nutrients ; 14(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35215417

RESUMO

Metabolic detoxification (detox)-or biotransformation-is a physiological function that removes toxic substances from our body. Genetic variability and dietary factors may affect the function of detox enzymes, thus impacting the body's sensitivity to toxic substances of endogenous and exogenous origin. From a genetic perspective, most of the current knowledge relies on observational studies in humans or experimental models in vivo and in vitro, with very limited proof of causality and clinical value. This review provides health practitioners with a list of single nucleotide polymorphisms (SNPs) located within genes involved in Phase I and Phase II detoxification reactions, for which evidence of clinical utility does exist. We have selected these SNPs based on their association with interindividual variability of detox metabolism in response to certain nutrients in the context of human clinical trials. In order to facilitate clinical interpretation and usage of these SNPs, we provide, for each of them, a strength of evidence score based on recent guidelines for genotype-based dietary advice. We also present the association of these SNPs with functional biomarkers of detox metabolism in a pragmatic clinical trial, the LIFEHOUSE study.


Assuntos
Estilo de Vida , Medicina de Precisão , Marcadores Genéticos , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
5.
J Pers Med ; 12(1)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35055430

RESUMO

The working definition of health is often the simple absence of diagnosed disease. This common standard is limiting given that changes in functional health status represent early warning signs of impending health declines. Longitudinal assessment of functional health status may foster prevention of disease occurrence and modify disease progression. The LIFEHOUSE (Lifestyle Intervention and Functional Evaluation-Health Outcomes SurvEy) longitudinal research project explores the impact of personalized lifestyle medicine approaches on functional health determinants. Utilizing an adaptive tent-umbrella-bucket design, the LIFEHOUSE study follows the functional health outcomes of adult participants recruited from a self-insured employee population. Participants were each allocated to the tent of an all-inclusive N-of-one case series. After assessing medical history, nutritional physical exam, baseline functional status (utilizing validated tools to measure metabolic, physical, cognitive, emotional and behavioral functional capacity), serum biomarkers, and genomic and microbiome markers, participants were assigned to applicable umbrellas and buckets. Personalized health programs were developed and implemented using systems biology formalism and functional medicine clinical approaches. The comprehensive database (currently 369 analyzable participants) will yield novel interdisciplinary big-health data and facilitate topological analyses focusing on the interactome among each participant's genomics, microbiome, diet, lifestyle and environment.

6.
Mult Scler Relat Disord ; 55: 103201, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34391041

RESUMO

INTRODUCTION: The data of the survey of European (EU) neurologists on the methods of diagnosis and treatment of multiple sclerosis in Europe were compared with the data of the similar survey of neurologists of the Russian Federation (RF). METHOD: Seventy-five neurologists specialized in MS from RF completed questionnaires on radiologically isolated syndrome (RIS), clinically isolated syndrome (CIS), relapsing-remitting (RRMS), secondary progressive (SPMS), and primary progressive (PPMS) multiple sclerosis. RESULTS: In the case of RIS, only 46% of neurologists from the RF recommended CSF analysis for oligoclonal IgG and only 54.3% performed magnetic resonance imaging (MRI) of the spinal cord, which is significantly lower than in the EU (78% and 80%, respectively). In the case of CIS, significantly more neurologists from the Russian Federation would have tested for antibodies to disorders of the optical spectrum of neuromyelitis (57% in the EU and 94% in the RF). In case of typical RRMS, more neurologists from the RF preferred to start with the second line of disease-modifying therapy (DMT), a lower percentage would choose dimethyl fumarate as the first line DMT (9% in the RF and 25% in the EU). In case of escalating therapy, the majority of EU respondents (68%) indicated that one relapse would be sufficient (only 28% in RF), while in RF, 58% indicated that two relapses would be sufficient (22% in EU). Fewer neurologists from RF would use fingolimod, natalizumab or mitoxantrone for SPMS. 91% of neurologists in RF would like to prescribe ocrelizumab for PPMS. CONCLUSION: MS specialists from RF are less active in monitoring RIS than MS specialists from EU. CIS is not indication to use any DMT in RF. MS specialists in RF are more conservative in changing DMT as escalation in cases with breakthrough RRMS. The products without indication to be used in SPMS are rarely prescribed in RF in comparison to EU. Most cases of PPMS in RF would be treated with ocrelizumab.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/epidemiologia , Natalizumab/uso terapêutico , Federação Russa , Inquéritos e Questionários
7.
PLoS One ; 14(5): e0217303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31136608

RESUMO

BACKGROUND: NTZ is approved in Russia for the treatment of highly active relapsing remitting multiple sclerosis and is reimbursed via federal budget program. However, no data about NTZ treatment in Russia and the effect of federal reimbursement have been performed so far. OBJECTIVE: To characterize the population of patients receiving natalizumab and assess the efficacy and risk-management plan (RMP) implementation of NTZ therapy in routine clinical practice in Russia. METHODS: We analyzed data for 334 patients, who received at least one infusion of NTZ. Relapse rate, MRI activity, NEDA-3 status after 2 years were assessed. Anti-JC virus antibodies status and RMP implementation were evaluated. Drop-out rate and reasons for therapy discontinuation were analyzed. RESULTS: Patients switched to natalizumab in Russia are mainly female (63%), with median EDSS score of 3.5 and high disease activity: 93% had at least 1 relapse and 58% had both T1Gd+ and new T2 lesion a year before therapy initiation. Introduction of federal reimbursement allowed patients with less relapses to start therapy with natalizumab. The only predictor of 6-month progression was EDSS score at the baseline of therapy (HR = 2.1375, 95%CI 1.0026-4.5570, p = 0.0492). 82% patients reached NEDA-3 at 24 month of therapy. 25% of patients discontinued NTZ for reasons: tolerability (14.5%), JCV antibody status (61%), and patient's decision (17%). RMP was implemented in only 36% patients. CONCLUSION: Natalizumab appeared to have high efficacy in Russian clinical practice. Federal reimbursement allowed less active patients to start natalizumab. More efforts should be done to improve RMP implementation.


Assuntos
Fatores Imunológicos/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Natalizumab/uso terapêutico , Adulto , Estudos Transversais , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Leucoencefalopatia Multifocal Progressiva/etiologia , Leucoencefalopatia Multifocal Progressiva/prevenção & controle , Masculino , Natalizumab/administração & dosagem , Natalizumab/efeitos adversos , Estudos Retrospectivos , Gestão de Riscos , Federação Russa , Resultado do Tratamento , Adulto Jovem
8.
Global Spine J ; 7(6): 506-513, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28894679

RESUMO

STUDY DESIGN: Retrospective consecutive case series. OBJECTIVE: The objective of this case series was to demonstrate the safety of a modified transfacet pedicle-sparing decompression and instrumented fusion in patients with thoracic disc herniations (TDHs). METHODS: Consecutive patients undergoing operative management of TDH from July 2007 to December 2011 using a posterior unilateral modified transfacet pedicle-sparing approach were identified. All patients underwent open or minimally invasive modified transfacet pedicle-sparing discectomy and segmental instrumentation with interbody fusion, performed by four different surgeons. Pre- and postoperative visual analog scale (VAS) pain scores, Nurick grade, and American Spinal Injury Association Impairment Scale (AIS) were analyzed from a retrospective chart review. Estimated blood loss and complications were also obtained. RESULTS: Fifty-one patients were included that had operations for TDH. Thirty-nine patients had single level decompression and 12 had multilevel decompression. The total number of levels operated on was 64. Five patients were treated with minimally invasive surgery. A herniated disc level of T11-12 (n = 17) was treated most often. One major complication of epidural hematoma occurred. Minor complications such as malpositioned hardware, postoperative hematoma, wound infection, pseudoarthrosis, and pulmonary complications occurred in a few patients. Follow-up ranged from 1 to 46 months with 1 patient lost to follow-up. From preoperative to final postoperative: mean VAS scores improved from 8.31 to 4.05, AIS in all patients remained stable or improved, and Nurick scores improved from 3 to 2.6 on average. No intraoperative or permanent neurological deficit occurred. CONCLUSION: In our surgical series, 51 consecutive patients underwent modified transfacet pedicle-sparing approach to TDHs and experienced improvement of functional status as well as improvement of objective pain scales with no neurological complications. The posterior unilateral modified transfacet pedicle-sparing decompression and instrumented fusion approach to the thoracic spine is a safe and reproducible procedure for the treatment of TDHs.

9.
Cancer Control ; 24(1): 47-53, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28178712

RESUMO

BACKGROUND: Advancements in cancer treatment have led to more cases of leptomeningeal disease, which requires a multimodal approach. METHODS: Treatment modalities are reviewed from a neurosurgical standpoint, focusing on intrathecal chemotherapy and shunting devices. Potential complications and how to avoid them are discussed. RESULTS: The Ommaya reservoir and the chemoport are used for administering intrathecal chemotherapy. Use of ventriculo-lumbar perfusion can efficiently deliver chemotherapeutic agents and improve intracerebral pressure. Shunting systems, in conjunction with all of their variations, address the challenge of hydrocephalus in leptomeningeal carcinomatosis. Misplaced catheters, malfunction of the system, and shunt-related infections are known complications of treatment. CONCLUSIONS: From an oncological perspective, the surgical treatment for leptomeningeal disease is limited; however, neurosurgery can be used to aid in the administration of chemotherapy and address the issue of hydrocephalus. Minimizing surgical complications is important in this sensitive patient population.


Assuntos
Neoplasias Meníngeas/cirurgia , Humanos , Prognóstico
10.
Turk Neurosurg ; 25(6): 954-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617149

RESUMO

Tophaceous gout has classically been described as an affliction of the extremities. It has however been reported as early as 1947 to involve the spinal column. We report a 63-year-old male, previously scheduled for Anterior Cervical Discectomy and Fusion to correct an existing cervical myelopathy at the C3-C4 spinal level, who presented to the emergency room with progressive weakness of the lower extremities and inability to ambulate for three days. Physical examination suggested a possible worsening of his cervical myelopathy but magnetic resonance imaging (MRI) findings remained unchanged from comparison studies. On the day of surgery, he became febrile and complained of excruciating back pain and we therefore initiated an infectious etiology workup and obtained a lumbar spine MRI. Results of imaging suggested a lumbar epidural abscess with effacement of the thecal sac. Emergent L4-L5 decompression led to an evacuation of a "chalky" substance, which was sent for pathology evaluation. This patient was diagnosed with tophaceous gout of the lumbar spine upon final pathological review. We aim to present the management of this case and review the literature associated with this diagnosis with the goal of improving the approach taken to diagnose and treat this pathology.


Assuntos
Gota/patologia , Descompressão Cirúrgica , Abscesso Epidural/etiologia , Abscesso Epidural/cirurgia , Gota/cirurgia , Humanos , Vértebras Lombares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
11.
Turk Neurosurg ; 25(2): 344-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26014027

RESUMO

Biventricular hydrocephalus caused by a Giant Basilar Apex Aneurysm (GBAA) is a rare finding that presents unique and challenging treatment decisions. We report a case of GBAA causing a life-threatening biventricular hydrocephalus in which both the aneurysm and hydrocephalus were given definitive treatment through a staged, minimally invasive approach. An obtunded 82-year-old male was found to have biventricular hydrocephalus caused by an unruptured GBAA obstructing the foramina of Monro. The patient was treated via staged, minimally invasive technique that first involved endoscopic fenestration of the septum pellucidum to create communication between the lateral ventricles. A programmable ventriculo-peritoneal shunt was then placed with a high-pressure setting. The patient was then loaded with dual anti-platelet therapy prior to undergoing endovascular coiling of the GBAA with adjacent stenting of the Posterior Cerebral Artery. He remained on dual anti-platelet therapy and the shunt setting was lowered at the bedside to treat the hydrocephalus. At 6-month follow up, the patient had returned to his cognitive baseline, speaking fluently and appropriately. Biventricular hydrocephalus caused by a GBAA can successfully be treated in a minimally invasive fashion utilizing a combination of endoscopy and endovascular therapy, even when a stent-assisted coiling is needed.


Assuntos
Embolização Terapêutica/métodos , Hidrocefalia/cirurgia , Aneurisma Intracraniano/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neuroendoscopia/métodos , Derivação Ventriculoperitoneal/métodos , Idoso de 80 Anos ou mais , Humanos , Hidrocefalia/diagnóstico , Hidrocefalia/etiologia , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Ventrículos Laterais/patologia , Ventrículos Laterais/cirurgia , Masculino
12.
J Neurosurg Spine ; 20(2): 209-19, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24286528

RESUMO

OBJECT: In this paper the authors evaluate through in vitro biomechanical testing the performance of an interspinous fusion device as a stand-alone device, after lumbar decompression surgery, and as supplemental fixation to expandable cages in a posterior lumbar interbody fusion (PLIF) construct. METHODS: Nine L3-4 human cadaveric spines were biomechanically tested under the following conditions: 1) intact/control; 2) L3-4 left hemilaminotomy with partial discectomy (injury); 3) interspinous spacer (ISS); 4) bilateral pedicle screw system (BPSS); 5) bilateral hemilaminectomy, discectomy, and expandable posterior interbody cages with ISS (PLIF-ISS); and 6) PLIF-BPSS. Each test consisted of 100 N of axial preload with ± 7.5 Nm of torque in flexion-extension, right/left lateral bending, and right/left axial rotation. Significant changes in range of motion (ROM), neutral zone stiffness (NZS), elastic zone stiffness (EZS), and energy loss (EL) were explored among conditions using nonparametric Friedman test and Wilcoxon signed-rank comparisons (p ≤ 0.05). RESULTS: The injury increased ROM in flexion (p = 0.01), left bending (p = 0.03), and right/left rotation (p < 0.01) and also decreased NZS in flexion (p = 0.01) and extension (p < 0.01). Both the ISS and BPSS reduced flexion-extension ROM and increased flexion-extension stiffness (NZS and EZS) with respect to the injury and intact conditions (p < 0.05), but the ISS condition provided greater resistance than BPSS in extension for ROM, NZS, and EZS (p < 0.01). The BPSS increased the rigidity (ROM, NZS, and EZS) of the intact model in lateral bending and axial rotation (p ≤ 0.01), except in EZS for left rotation (p = 0.23, Friedman test). The incorporation of posterior cages marginally increased (p = 0.05) the EZS of the BPSS construct in flexion but these interbody devices provided significant stability to the ISS construct in lateral bending and axial rotation for ROM (p = 0.02), in lateral bending for NZS (p = 0.02), and in flexion/axial rotation for EZS (p ≤ 0.03); however, both PLIF constructs demonstrated equivalent ROM and stiffness (p ≥ 0.16), except in lateral bending where the PLIF-BPSS was more stable (p = 0.02). In terms of EL, the injury increased EL in flexion-extension (p = 0.02), the ISS increased EL for lateral bending and axial rotation (p ≤ 0.03), and the BPSS decreased EL in lateral bending (p = 0.02), with respect to the intact condition. The PLIF-ISS decreased lateral bending EL with respect to the ISS condition (p = 0.02), but not enough to be smaller or, at least, equivalent, to that of the PLIF-BPSS construct (p = 0.02). CONCLUSIONS: The ISS may be a suitable device to provide immediate flexion-extension balance after a unilateral laminotomy, but the BPSS provides greater immediate stability in lateral bending and axial rotation motions. Both PLIF constructs performed equivalently in flexion-extension and axial rotation, but the PLIF-BPSS construct is more resistant to lateral bending motions. Further biomechanical and clinical evidence is required to strongly support the recommendation of a stand-alone interspinous fusion device or as supplemental fixation to expandable posterior interbody cages.


Assuntos
Vértebras Lombares/cirurgia , Amplitude de Movimento Articular/fisiologia , Fusão Vertebral/métodos , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Parafusos Ósseos , Humanos , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Fusão Vertebral/instrumentação
13.
World Neurosurg ; 81(3-4): 603-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24140999

RESUMO

OBJECTIVE: This study sought to describe the operative technique and clinical outcomes in a series of 57 patients with trigeminal neuralgia treated with endoscopic vascular decompression (EVD) alone without the use of microscopy at any point. METHODS: A prospective observational study was performed on 57 consecutive patients treated with EVD alone for trigeminal neuralgia from October 2005 to October 2010. Patient outcomes were evaluated with respect to pain abatement, complication rate, length of hospital stay, and overall operative time. Pain outcome was graded using the Barrow Neurological Institute pain intensity score (BNI), with BNI 1 considered an excellent result and BNI 2 or 3 considered a good result. Follow-up ranged from 12 to 72 months, with a mean of 32 months. In addition to reporting these cases, our operative technique for EVD is described in detail. RESULTS: All 57 patients reported severe preoperative pain (BNI 5); 100% of patients achieved immediate postoperative pain control or complete pain relief (BNI 1 to 3), with 82% obtaining an excellent result of BNI 1, and 18% of patients reported good results of BNI 2 or 3. At follow-up, 56 of 57 patients (98%) reported complete relief or well controlled pain (BNI 1 to 3), with 75% obtaining an excellent result of BNI 1; 23% of patients obtained a good result of BNI 2 or 3. The complication rate was 4%, with no mortality. Mean length of hospital stay was 1.6 days, with a range of 1 to 5 days; mean operative time was 133 minutes. CONCLUSIONS: EVD is a safe and highly effective alternative to the more traditional open microvascular decompression or the more recently developed endoscopically assisted microvascular decompression.


Assuntos
Ângulo Cerebelopontino/cirurgia , Cirurgia de Descompressão Microvascular/métodos , Neuroendoscopia/métodos , Base do Crânio/cirurgia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Cerebelo/irrigação sanguínea , Artérias Cerebrais/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Resultado do Tratamento
14.
Environ Sci Technol ; 43(14): 5521-8, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19708391

RESUMO

We found high levels of contaminants, in particular organochlorines, in eggs of the ivory gull Pagophila eburnea, a high Arctic seabird species threatened by climate change and contaminants. An 80% decline in the ivory gull breeding population in the Canadian Arctic the last two decades has been documented. Because of the dependence of the ivory gull on sea ice and its high trophic position, suggested environmental threats are climate change and contaminants. The present study investigated contaminant levels (organochlorines, brominated flame retardants, perfluorinated alkyl substances, and mercury) in ivory gull eggs from four colonies in the Norwegian (Svalbard) and Russian Arctic (Franz Josef Land and Severnaya Zemlya). The contaminant levels presented here are among the highest reported in Arctic seabird species, and we identify this as an important stressor in a species already at risk due to environmental change.


Assuntos
Charadriiformes , Ovos , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Animais , Regiões Árticas , Conservação dos Recursos Naturais , Exposição Ambiental , Noruega , Federação Russa
15.
Childs Nerv Syst ; 22(12): 1519-25, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17021732

RESUMO

INTRODUCTION: Diffuse pontine gliomas remain a challenging and frustrating disease to treat. The survival rates for these high-grade brainstem tumors (BSTs) is dismal and optimal therapy has yet to be determined. The development of a satisfactory brainstem tumor model is necessary for testing new therapeutic paradigms that may prolong survival. MATERIALS AND METHODS: We report the surgical technique, functional testing, and histopathological features of a novel brainstem tumor model in rats. Female Fischer 344 rats (n=45) were randomized to receive an injection of either 3 microl of 9L gliosarcoma cells (100,000 cells, n=), 3 microl of F98 glioma cells (100,000 cells, n=10), or 3 microl of medium (Dulbecco's modified eagle medium) into the pontine tegmentum. Using a cannulated guide screw system, implanted in the skull of the animal, we injected each group at coordinates 1.4 mm right of the sagittal and 1.0 mm anterior of the lambdoid sutures, at a depth of 7.0 mm from the dura. The head was positioned 5 degrees from horizontal before injection. The rats were post-operatively evaluated for neurological deficits using an automated test. Kaplan-Meier curves were generated for survival and disease progression, and brains were processed postmortem for histopathology. RESULTS AND DISCUSSION: 9L and F98 tumor cells grew in 100% of animals injected and resulted in a statistically significant mean onset of hemiparesis of 16.5+/-0.56 days (P=0.001, log-rank test), compared to animals in the control group which lacked neurological deficits by day 60. The animals with tumor cells implanted demonstrated significant deterioration of function on the automated rod testing. Animals in the control group showed no functional or pathological signs of tumor. Progression to hemiparesis was consistent in all tumor-injected animals, with predictable onset of symptoms occurring approximately 17 days post-surgery. The histopathological characteristics of the 9L and F98 BSTs were comparable to those of aggressive human BSTs. CONCLUSION: The establishment of this animal tumor model will facilitate the testing of new therapeutic paradigms for the treatment of BSTs.


Assuntos
Neoplasias do Tronco Encefálico/patologia , Modelos Animais de Doenças , Gliossarcoma/patologia , Transplante de Neoplasias/métodos , Ratos Endogâmicos F344 , Animais , Neoplasias do Tronco Encefálico/fisiopatologia , Feminino , Glioma/patologia , Glioma/fisiopatologia , Gliossarcoma/fisiopatologia , Atividade Motora , Procedimentos Neurocirúrgicos , Ratos , Taxa de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA