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BACKGROUND AND PURPOSE: Transient tumor swelling is a well-known phenomenon following radiotherapy for vestibular schwannomas (VS). We analyzed the long-term volumetric changes of VS after LINAC radiosurgery, in order to determine a time interval during which a true tumor progression can be distinguished from a pseudoprogression. METHODS: Among 63 patients with VS treated by one fraction or fractionated radiotherapy, we selected 52 of them who had a minimal follow-up of 5 years. Maximal axial diameter and three-dimensional tumor volume were measured on each MRI scan. Volume changes were interpreted using different error margins ranging from 10 to 20%. Patients were categorized according to the tumor evolution pattern over time. RESULTS: Median follow-up was 83 months. One tumor (1.9%) remained stable and 26.9% had continuous shrinkage. Applying an error margin of 13%, a transient tumor enlargement was observed in 63.5% of patients, with a first peak at 6-12 months and a late peak at 3-4 years. A true progression was suspected in 4 (7.7%) patients, tumor regrowth starting after the 3rd or 4th year post-treatment. Only one patient required salvage radiotherapy. CONCLUSION: Transient swelling of VS following radiotherapy is generally an early phenomenon but may occur late. In the first 5 years, a true tumor progression cannot be differentiated from a pseudoprogression. A significant tumor expansion observed on 3 sequential MRI scans after the 3rd year may be suggestive of treatment failure. Long-term follow-up is therefore mandatory and no decision of salvage treatment should be made until the 6th year.
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PURPOSE: The ultimate goal of stereotactic radiotherapy (SRT) of brain metastases (BM) is to avoid or postpone whole brain radiotherapy (WBRT). A nomogram based on multi-institutional data was developed by Gorovets, et al. to estimate the 6 and 12-months WBRT-free survival (WFS). The aim of the current retrospective study was to validate the nomogram in a cohort of postoperative BM patients treated with adjuvant SRT. MATERIAL AND METHODS: We reviewed the data of 68 patients treated between 2008-2017 with postoperative SRT for BM. The primary endpoint was the WFS. The receiver operating characteristic curve and area under the curve (AUC) were calculated for both 6- and 12-months time points. RESULTS: After a median follow-up of 64 months, the 1-year cumulative incidence of local and distant brain relapse rates were 15% [95% CI=8-26%] and 34% [95% CI=24-48%], respectively. At recurrence, repeated SRT or salvage WBRT were applied in 33% and 57% cases, respectively. The WFS rates at 6 and 12 months were 88% [95% CI=81-97%] and 67% [95% CI=56-81%], respectively. Using the Gorovets nomogram, the 6 months rates were overestimated while they were accurate at 12 months. AUC values were 0.47 and 0.62 for the 6- and 12-months respectively. Overall, Harrell's concordance index was 0.54. CONCLUSION: This nomogram-predicted well the 12 months WFS but its discriminative power was quite low. This underlines the limits of this kind of predictive tool and leads us to consider the use of big data analysis in the future.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Irradiação Craniana , Nomogramas , Radiocirurgia/métodos , Terapia de Salvação/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/cirurgia , Intervalos de Confiança , Irradiação Craniana/estatística & dados numéricos , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Período Pós-Operatório , Curva ROC , Radiocirurgia/estatística & dados numéricos , Estudos Retrospectivos , Terapia de Salvação/estatística & dados numéricos , Fatores de TempoRESUMO
PURPOSE: To retrospectively analyze the outcomes of stereotactic radiotherapy (SRT) targeted at surgical bed of brain metastases (BM) and identify patterns of local/distant brain relapses (LR/DBR). PATIENTS/METHODS: Seventy patients were treated with SRT between 2008-2017. Marginal dose prescription on the 70% isodose line depended on the maximal diameter of the target volume and range between 15-18Gy for single fraction radiosurgery and 23.1-26Gy in 3-5 fractions for fractionated SRT. RESULTS: At 12 months, the overall survival (OS) was 69% [CI 95%=59%-81%]. At 6 and 12 months, the cumulative incidence functions (CIF) of local relapse were 4% [1%-13%] and 15% [8%-26%], respectively. According to univariate analysis, factors associated with LR were an initial volume larger than 7cc (hazard ratio: 4.6 [1.0-20.8], P=0.046) and a positive resection margin [hazard ratio: 3.6 [1.1-12.0], P=0.037. DBR occurred in 54.3% of patients with a median time of 8 months. None of the variables tested (histology, location or number of lesions) were found correlated with the DBR. Leptomeningeal disease occurred in 12.9% of cases. Salvage whole brain radiotherapy (WBRT) was required in 45.7% of patients and delayed by a median time of 9.6 months. Symptomatic radionecrosis (RN) occurred in 7.1%. CONCLUSIONS: Adjuvant SRT was an effective and well-tolerated treatment to control the postoperative risk of recurrence of BM without compromising OS. Positive resection margins and large volumes were predictors factor of local relapse.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Irradiação Craniana/estatística & dados numéricos , Feminino , Humanos , Masculino , Margens de Excisão , Neoplasias Meníngeas/epidemiologia , Pessoa de Meia-Idade , Necrose/epidemiologia , Recidiva Local de Neoplasia , Intervalo Livre de Progressão , Lesões por Radiação/epidemiologia , Radiocirurgia/mortalidade , Dosagem Radioterapêutica , Estudos Retrospectivos , Terapia de Salvação/estatística & dados numéricos , Resultado do Tratamento , Carga TumoralRESUMO
OBJECTIVE: To assess and compare, clinically and electrophysiologically, the effects on muscle innervation and spasticity of selective anaesthetic nerve block and selective neurotomy of the motor-nerve branch to the soleus muscle in patients with spastic equinus foot. METHODS: Eleven hemiplegic patients were studied before and after anaesthetic tibial-nerve block, and at two months and one year after tibial nerve neurotomy. Triceps surae spasticity and strength, walking speed, gait kinematics of the ankle, maximal amplitude of the H reflex and of the M-response and the Hmax/Mmax ratio of the soleus muscle, and the mean motor unit action potential area and motor unit number estimation (MUNE) of the soleus muscle were calculated on the normal and spastic side. RESULTS: Spasticity and equinovarus improved in a similar fashion after tibial nerve block and neurotomy. The soleus Hmax/Mmax ratio decreased by 42% after tibial nerve block and 77% after neurotomy. The soleus MUNE decreased by 52% after tibial nerve block and by 86% after neurotomy. CONCLUSION: Diagnostic nerve block predicts the spasticity and gait improvement, which is expected after neurotomy. The clinical improvement was similar after block and neurotomy. Nerve block is associated with a 50% decrease in the soleus Hmax/Mmax ratio and soleus MUNE. The median 80% neurotomy is associated with an 80% decrease in the soleus Hmax/Mmax ratio and soleus MUNE.
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Deformidades Adquiridas do Pé/fisiopatologia , Reflexo H/fisiologia , Neurônios Motores/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Espasticidade Muscular/fisiopatologia , Músculo Esquelético/fisiopatologia , Bloqueio Nervoso , Nervo Tibial , Potenciais de Ação/fisiologia , Adulto , Fenômenos Biomecânicos , Eletrofisiologia , Feminino , Marcha , Hemiplegia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/inervação , Estudos ProspectivosRESUMO
Ventricular schwannomas are very uncommon. We report such a tumor in the right lateral ventricle of a 16-year-old young man. The various etiopathogenic hypotheses are discussed.
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Neoplasias do Ventrículo Cerebral/cirurgia , Neurilemoma/cirurgia , Adolescente , Neoplasias do Ventrículo Cerebral/patologia , Epilepsias Parciais/etiologia , Humanos , Imuno-Histoquímica , Ventrículos Laterais/patologia , Imageamento por Ressonância Magnética , Masculino , Neurilemoma/patologia , Procedimentos Neurocirúrgicos , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: Internet has become the first place where patients go to when seeking information about their disease. Little is known about the type and the quality of the medical information available on French-speaking websites, especially in the field of neuro-oncology. The purpose of this study was to evaluate the quality of these sites. MATERIALS AND METHODS: We entered six key words "glioblastome", "méningiome", "métastase cérébrale", "neurinome de l'acoustique", "adénome à prolactine" and "lymphome primitif cérébral" into 2 different search engines and, for each key word, the first fifty websites were reviewed using the tool "DISCERN", and with the help of two neuro-oncologists, we rated their content in terms of quality and comprehension. RESULTS: On 612 websites only 110 (18%) contained information that proved to be somewhat useful to patients. The average score for quality was 32, which is considered to be <
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Disseminação de Informação , Internet , Neoplasias do Sistema Nervoso , França , Armazenamento e Recuperação da Informação , Internet/normas , Idioma , Neurocirurgia , Educação de Pacientes como AssuntoRESUMO
The antitumorigenic effects of endogenous opioid peptides and their presence in extracerebral tumors are well documented. In this study, methionine-enkephaline (met-enkephalin) was measured by radioimmunoassay in 108 glial and nonglial brain tumors and in 44 associated cyst fluids. By immunohistochemistry, the distribution of the peptide and its precursor, preproenkephalin A, was also analyzed. Met-enkephalin and preproenkephalin were detected in the cytoplasm and cell processes of all tumors. Moreover, for neuroectodermal tumors (i.e., gliomas, gangliogliomas, and dysembryoplastic neuroepithelial tumors), a strong inverse correlation (P < 0.0001) was observed between the met-enkephalin levels and the degree of malignancy (242.9, 148.3, 55.3, and 30.3 pg/mg protein for grade 1, 2, 3, and 4, respectively). When compared to normal tissue, this differential expression mainly results from a decrease in the opioid peptide content in high-grade neuroectodermal tumors. Meningiomas and cerebral metastases displayed low met-enkephalin levels, similar to those of grade 4 neuroectodermal tumors. Large amounts of met-enkephalin were found in all cyst fluids. These data suggest that the endogenous opioid system is an integral component of brain tumors and that met-enkephalin may represent a useful malignancy marker in neuroectodermal tumors.
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Neoplasias Encefálicas/química , Neoplasias Encefálicas/patologia , Cistos/química , Cistos/patologia , Encefalina Metionina/análise , Encefalinas/análise , Glioma/química , Glioma/patologia , Precursores de Proteínas/análise , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/cirurgia , Cistos/classificação , Cistos/cirurgia , Proteína Glial Fibrilar Ácida/análise , Glioma/classificação , Glioma/cirurgia , Humanos , Imuno-Histoquímica , RadioimunoensaioRESUMO
Intracranial meningiomas are generally slow-growing neoplasms. Symptoms depend on their critical intracranial location. The authors describe a case of rapidly enlarging meningioma that became symptomatic as a result of invasion by leukemic cells at the time of a blastic crisis in the context of chronic myeloid leukemia. Infiltration of an intracranial meningioma by cells from extracranial malignant neoplasms is a rare event. Even though central nervous system (CNS) or meningeal involvement is common in some hematologic malignancies, this is, to the best of our knowledge, the first report of invasion of an intracranial meningioma by leukemic cells.
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Infiltração Leucêmica/patologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Idoso , Neoplasias da Mama , Evolução Fatal , Feminino , Humanos , Neoplasias Primárias Múltiplas/patologiaRESUMO
Anti-normal brain antibodies were studied in glioma cyst fluids. Cyst fluids were obtained by stereotaxic puncture from 34 patients with cystic gliomas. Immunoglobulins were analyzed by immunohistochemistry, immuno-Western blotting, concentration measures, and isoelectrofocalization. 80% of cyst fluids stained astrocytes and/or microvessels in non-tumoral white matter. In white matter extracts, cyst fluids recognized five immunoreactive bands having apparent molecular masses of 50-75 kDa. Although cyst proteins could be of systemic origin, isoelectrofocalization analysis suggests an additional local immune response. These antibody activities could be involved in certain peritumoral events such as brain edema.
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Autoanticorpos/análise , Líquidos Corporais/imunologia , Neoplasias Encefálicas/imunologia , Encéfalo/imunologia , Cistos/imunologia , Glioma/imunologia , Western Blotting , Eletroforese em Gel Bidimensional , Humanos , Imunodifusão , Técnicas Imunoenzimáticas , Focalização IsoelétricaRESUMO
The authors describe an unusual case of a complex traumatic fracture-dissociation injury of the craniovertebral junction, which the patient survived with no neurological damage. This case featured the rare combination of an avulsion of both the right occipital condyle and clivus and a fracture of the left lateral mass of the atlas. Because of the craniocervical ligament injury and the slight anterior occipitoatlantal dislocation, the lesion was considered to be unstable and was treated successfully with a cervical collar. The authors emphasize that thin-slice computerized tomography scanning with multiplanar reconstructions is essential to visualize these fractures, whereas magnetic resonance imaging is useful to assess soft tissues.
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Articulação Atlantoccipital/lesões , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/fisiopatologia , Sistema Nervoso/fisiopatologia , Adulto , Articulação Atlantoccipital/diagnóstico por imagem , Articulação Atlantoccipital/patologia , Fraturas Ósseas/terapia , Humanos , Imageamento por Ressonância Magnética , Masculino , Aparelhos Ortopédicos , Tomografia Computadorizada por Raios XRESUMO
OBJECT: In cases of spondylosis or spine trauma, cervical interbody grafts are sometimes required after anterior discectomy. To avoid morbidity related to the harvesting of iliac crest bone, numerous materials have been developed such as allografts, methylmethacrylate, biocompatible osteoconductive polymer, and coralline grafts or cages. Some of these materials, however, are inefficient for fusion or are associated with specific complications. Conversely, hydroxyapatite (HA) grafts have numerous advantages. For example, their mechanical properties provide adequate load resistance and their porosity allows infiltration by newly formed bone, leading to complete fusion. The authors studied the results of using HA grafts combined with plating in patients who underwent anterior cervical discectomy. METHODS: Fifty-four patients underwent 68 cervical interbody fusion procedures in which an HA graft and plating were used. Indications for surgery were radiculopathy (caused by soft-disc herniation or spondylosis) in 46 cases, spondylotic myelopathy in two cases, and spinal trauma in six cases. Postoperatively the patients were followed for a mean of 24.6 months. Patients underwent radiography to evaluate fusion, intervertebral disc height, and the degree of lordosis. Clinically, excellent or good results (based on the Odon classification) were demonstrated in 91% of patients who presented with radiculopathy. Complete interbody fusion was achieved in 99% of all cases. Preoperative kyphotic deformities were corrected in all cases after surgery. Intervertebral disc height was maintained throughout follow up. Surgery-related morbidity was low; only one patient suffered from a permanent dysphagia. Graft deterioration was observed in 13 cases and two graft fractures occurred but without adversely affecting fusion. There were no cases of graft extrusion. CONCLUSIONS: Hydroxyapatite grafts are very efficient in achieving cervical fusion, maintaining intervertebral disc height, and restoring lordosis. When combined with the placement of a cervical plate, immediate stability is achieved and graft displacement is prevented.
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Materiais Biocompatíveis/uso terapêutico , Placas Ósseas , Vértebras Cervicais/cirurgia , Durapatita/uso terapêutico , Próteses e Implantes , Fusão Vertebral , Adulto , Idoso , Materiais Biocompatíveis/efeitos adversos , Parafusos Ósseos , Vértebras Cervicais/diagnóstico por imagem , Discotomia , Durapatita/efeitos adversos , Falha de Equipamento , Feminino , Humanos , Cifose/cirurgia , Masculino , Pessoa de Meia-Idade , Radiografia , Doenças da Coluna Vertebral/cirurgia , Traumatismos da Coluna Vertebral/cirurgia , Resultado do TratamentoRESUMO
PURPOSE: To review and discuss the complications of minimally invasive pectus excavatum repair. METHODS: 329 patients underwent minimally invasive pectus repair between January 1987 and August 2000, including 14 patients who recurred after previous Ravitch repairs, 10 failed Nuss repairs (eight done elsewhere) and two failed Leonard repairs. All patients received antibiotics and vigorous incentive spirometry to prevent atelectasis, pneumonia and bar infection. Epidural anesthesia was used for postoperative analgesia to keep patients comfortable and stable postoperatively and to prevent bar displacement. Thoracoscopy was used during bar insertion to minimize the risk of mediastinal injury and to select the best position for the bar. A new introducer was developed to elevate the sternum before bar insertion. A stabilizing bar was created to minimize bar displacement. The duration of sternal bracing has been increased from two years to three or four years in selected patients. COMPLICATIONS: There were no deaths, no cardiac perforations and no cases of thoracic chondrodystrophy. Pneumothorax with spontaneous resolution occurred in 52 % of the patients, with 1.2 % requiring simple aspiration and 1.5 % requiring chest tube drainage. This complication has essentially been eliminated by using a "water seal system". Pericarditis occurred in 2.4 % with good response to Indomethacin in six out of eight patients and two patients also required pericardial fluid aspiration. Pneumonia occurred in 0.9 %. Wound infection occurred in 2.6 % resulting in bar infection in three out of the seven patients. Long-term antibiotics were successful in curing the infection in one patient, whereas the other two required bar removal at 12 and 18 months, respectively. Bar displacement occurred in 8.8 % of patients. However, the introduction of stabilizers decreased the incidence from 15.7 % before the use of stabilizers to 5.4 % with stabilizers. Wiring the bar and stabilizer together has decreased the incidence even further. RESULTS: Long-term outcome after bar removal showed an excellent result in 71 %, good result in 21 % and recurrence in 7.8 %. CONCLUSION: The minimally invasive technique has a low complication rate with excellent long-term results.
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Tórax em Funil/cirurgia , Complicações Pós-Operatórias/etiologia , Toracoscopia/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Lactente , Pericardite/etiologia , Pneumotórax/etiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Spasticity is usually treated by rehabilitation, orthosis, chemical denervations, orthopaedic surgery and neurosurgery. Selective fascicular neurotomy is a neurosurgical procedure consisting in partial section of selected motor nerves innervating spastic muscles. Neurotomy is indicated in cases of localised disabling spasticity without musculotendinous shortening, resistant to chemical denervation and for which a motor nerve block with anaesthetic has given a good functional result. Neurotomy includes division of the afferent Ia and Ib fibers, unable to recover, leading to permanent disappearance of the spasticity. Neurotomy also includes section of the motor efferent fibers with transient paresis as a result. In adults, neurotomy provides functional improvement in 81 to 97% of cases. In case of posterior tibial neurotomy, improved walking stability and a decrease in foot equinus and knee recurvatum is observed. In children, the risk of deformity recurrence seems higher because of motor axonal reinnervation: indications must therefore be carefully considered and rehabilitation provided after surgery.
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Paralisia Cerebral/complicações , Pé Equino/etiologia , Pé Equino/cirurgia , Denervação Muscular/métodos , Espasticidade Muscular/etiologia , Espasticidade Muscular/cirurgia , Vias Aferentes/cirurgia , Pessoas com Deficiência , Vias Eferentes/cirurgia , Humanos , Bloqueio Nervoso/métodos , Cuidados Pré-Operatórios , Recidiva , Resultado do TratamentoRESUMO
Cervical spinal fracture and pseudarthrosis are previously described causes of spinal cord injury (SCI) in patients with spondylarthropathy. SAPHO (Synovitis Acne Pustulosis Hyperostosis Osteitis) syndrome is a recently recognized rheumatic condition characterized by hyperostosis and arthro-osteitis of the upper anterior chest wall, spinal involvement similar to spondylarthropathies and skin manifestations including palmoplantar pustulosis and pustular psoriasis. We report the first case of SAPHO syndrome disclosed by SCI related to cervical spine ankylosis.
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Síndrome de Hiperostose Adquirida/complicações , Anquilose/complicações , Traumatismos da Medula Espinal/etiologia , Síndrome de Hiperostose Adquirida/diagnóstico por imagem , Síndrome de Hiperostose Adquirida/patologia , Idoso , Anquilose/diagnóstico por imagem , Anquilose/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia , Tomografia Computadorizada por Raios XRESUMO
Healthcare organizations are challenged to provide an environment that enhances professional growth. Miami Valley Hospital responded by examining its evaluation system for clinical nurses and designing a developmental evaluation process. The result is an objective position description outlining global responsibilities of a nurse and a comprehensive, unit-specific assessment of performance. As nurses are guided and nurtured in their development, the opportunities for them to excel are unlimited.
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Avaliação de Desempenho Profissional/organização & administração , Recursos Humanos de Enfermagem Hospitalar/normas , Desenvolvimento de Pessoal/métodos , Consultores , Avaliação de Desempenho Profissional/normas , Unidades Hospitalares/organização & administração , Humanos , Descrição de Cargo , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Ohio , Inovação OrganizacionalRESUMO
Thromboxane, prostacyclin and their ratio could play an important role in the ischemic liver injury. To study this hypothesis, thromboxane and prostacyclin were measured by RIA after incubation of liver tissues removed during and after an ischemia of 90 min in male Wistar rats. The thromboxane to prostacyclin ratio increases during this period. In order to examine if this change could influence the survival rate of animals submitted to the same period of ischemia, drugs able to reduce the relative predominance of thromboxane were infused. The survival rate was not modified by administration of Iloprost or Daltroban, the antagonist of the thromboxane receptors. By contrast, imidazole, an inhibitor of thromboxane synthetase, significantly increased the survival rate. The same result was obtained with the administration of Daltroban plus Iloprost, suggesting that the reduction of thromboxane action associated with the increase of PGI2 level reduces the ischemic injury.
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6-Cetoprostaglandina F1 alfa/análise , Isquemia/metabolismo , Fígado/irrigação sanguínea , Tromboxano B2/análise , Animais , Epoprostenol/farmacologia , Iloprosta , Imidazóis/farmacologia , Fígado/análise , Fígado/efeitos dos fármacos , Masculino , Fenilacetatos/farmacologia , Ratos , Ratos Endogâmicos , Sulfonamidas/farmacologiaRESUMO
The case of a 20-year-old man presenting with a rapidly expanding pituitary somatotrophic adenoma with a tumour volume doubling time of 426 days is reported. Preoperative octreotide therapy induced a 45% tumour shrinkage and proliferating cells were absent at the time of tumoural resection. The correlation between clinical and proliferation markers data in this single case report affords an opportunity to discuss the antitumoral effect of octreotide on somatotrophic adenomas which may result from a suppression of cell proliferation.
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Adenoma/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Hormônio do Crescimento/antagonistas & inibidores , Recidiva Local de Neoplasia/tratamento farmacológico , Octreotida/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Adenoma/diagnóstico , Adenoma/patologia , Adulto , Humanos , Masculino , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Resultado do TratamentoRESUMO
Using a rat C6 brain tumor model, we studied the antitumor effects of Herpes simplex virus type 1 thymidine kinase (HSV-tk) gene transfer followed by ganciclovir treatment. C6 glioma cells were transfected in vitro with the HSV-tk gene, and tested for their sensitivity to ganciclovir. Although there was no surviving cell at a 30 microM ganciclovir concentration, unmodified C6 cells were not affected by the drug. For in vivo experiments, intracerebral tumors were induced in rats by stereotactic injection of 10(4) HSV-tk-modified C6 cells. Ten days later, the animals were treated with intraperitoneal injections of ganciclovir for 21 days. The tumors evolution was evaluated by high resolution magnetic resonance imaging. In 33% of the rats, the signal intensity of the tumors became heterogeneous, with development of highly hyperintense areas, and a complete tumor regression was subsequently noted. Histological examination of successfully treated tumors revealed progressive necrosis with formation of cysts. The survival time of the HSV-tk/ganciclovir treated animals was consistently increased, all rats surviving more than 30 days and 33% of them being still alive after 80 days.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Imageamento por Ressonância Magnética , Simplexvirus/enzimologia , Animais , Neoplasias Encefálicas/patologia , Modelos Animais de Doenças , Ganciclovir/uso terapêutico , Técnicas de Transferência de Genes , Glioma/patologia , Masculino , Estadiamento de Neoplasias , Transplante de Neoplasias , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Taxa de Sobrevida , Timidina Quinase/genética , Timidina Quinase/uso terapêuticoRESUMO
In a rat model, the left kidney was subjected to 60 min of normothermic ischemia followed by 15 min of reperfusion, whereas the right kidney, serving as a paired control, was not rendered ischemic. Both kidneys were then perfused in situ with either Euro-Collins (EC) solution (n = 12) or University of Wisconsin (UW) solution (n = 6) for 10 min. Each kidney was then harvested and stored at 4 degrees C in its respective solution. After 24 and 48 h of cold storage, the following vasoactive substances were measured in the preservation media: endothelin (ET), angiotensin II (A-II), thromboxane (B2) (TxB2), and prostaglandin I2 (PGI2). After 24 h in EC solution, left kidneys uniformly produced significantly higher concentrations of each vasoactive substance than right kidneys: ET 1.64 +/- 0.3 pg/ml vs 0.82 +/- 0.1 pg/ml (P < or = 0.009); A-II 20.8 +/- 6.2 pg/ml vs 7.75 + 2.3 pg/ml (P < or = 0.007); TxB2 100.8 +/- 17.7 pg/ml vs 40.1 +/- 11.7 pg/ml (P < or = 0.04); PGI2 638.3 +/- 41.1 pg/ml vs 318.3 +/- 36.4 pg/ml (P < or = 0.001), respectively. At 48 h, a similar pattern of results was obtained as the kidney continued to produce TxB2 and prostacyclins during the 24-48 h period. In the UW solution, basal levels of ET and A-II were lower than those in EC solution, but similarly increased after initial ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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Angiotensina II/análise , Endotelinas/análise , Isquemia/diagnóstico , Transplante de Rim , Rim/irrigação sanguínea , Soluções para Preservação de Órgãos , Tromboxano B2/análise , Adenosina/química , Alopurinol/química , Animais , Criopreservação , Glutationa/química , Humanos , Soluções Hipertônicas/química , Insulina/química , Isquemia/metabolismo , Rim/metabolismo , Masculino , Preservação de Órgãos , Radioimunoensaio , Rafinose/química , Ratos , Ratos WistarRESUMO
The effects of an atrial natriuretic factor (ANF) infusion upon the production of the arachidonic acid metabolites (thromboxane B2, TxB2; 6-keto-prostaglandin F1 alpha, 6-keto-PGF1 alpha, PGI2, or prostaglandins E2, PGE2) were investigated after acute renal ischemia in the rat. This experimental protocol included a right nephrectomy and a 45-min left renal artery occlusion. Fifteen minutes after declamping, blood samples were collected from the left renal venous effluent for the assay of plasmatic prostanoid concentrations. Three experimental groups were studied: group I (n = 9) sham, no ischemia-group II (n = 9) control group, 45 min of left renal ischemia, followed by a 15-min revascularization, and group III (n = 10) ANF group, a similar ischemic protocol to that in group II was used but, after declamping, synthetic Atriopeptin III was infused (0.5 micrograms/kg/min) during the 15-min of vascular reflow. Fifteen minutes after declamping, TxB2 secretion significantly increased after ischemia in the control and ANF groups: TxB2: 210 +/- 22.4 pg/ml (control group) and 234.8 +/- 25.1 pg/ml (ANF group) versus 135.8 +/- 17.8 pg/ml (sham group) (p less than 0.05 and 0.01, respectively). On the other hand, the 6-keto-PGF1 alpha plasma levels were significantly higher after ischemia in the ANF group (221 +/- 34 pg/ml) in comparison with the sham (124 +/- 24.1 pg/ml) or with the control group (116.7 +/- 12.5 pg/ml). The calculated TxB2/6-keto-PGF1 alpha ratio was therefore higher in the control group, 1.93 +/- 0.27, than in physiological conditions (sham group), 1.2 +/- 0.17.(ABSTRACT TRUNCATED AT 250 WORDS)