RESUMO
Eleginops maclovinus is an endemic fish to Chile that lives in proximity to salmonid culture centers, feeding off of uneaten pellet and salmonid feces. Occurring in the natural environment, this interaction between native and farmed fish could result in the horizontal transmission of pathogens affecting the aquaculture industry. The aim of this study was to evaluate the innate and adaptive immune responses of E. maclovinus challenged with P. salmonis. Treatment injections (in duplicate) were as follows: control (100⯵L of culture medium), wild type LF-89 strain (100⯵L, 1â¯×â¯108 live bacteria), and antibiotic resistant strain Austral-005 (100⯵L, 1â¯×â¯108 live bacteria). The fish were sampled at various time-points during the 35-day experimental period. The gene expression of TLRs (1, 5, and 8), NLRCs (3 and 5), C3, IL-1ß, MHCII, and IgMs were significantly modulated during the experimental period in both the spleen and gut (excepting TLR1 and TLR8 spleen expressions), with tissue-specific expression profiles and punctual differences between the injected strains. Anti-P. salmonis antibodies increased in E. maclovinus serum from day 14-28 for the LF-89 strain and from day 14-35 for the Austral-005 strain. These results suggest temporal activation of the innate and adaptive immune responses in E. maclovinus tissues when injected by distinct P. salmonis strains. The Austral-005 strain did not always cause the greatest increases/decreases in the number of transcripts, so the magnitude of the observed immune response (mRNA) may not be related to antibiotic resistance. This is the first immunological study to relate a pathogen widely studied in salmonids with a native fish.
Assuntos
Imunidade Adaptativa , Doenças dos Peixes/imunologia , Imunidade Inata , Perciformes/imunologia , Piscirickettsia/fisiologia , Infecções por Piscirickettsiaceae/veterinária , Animais , Regiões Antárticas , Chile , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Piscirickettsia/genética , Infecções por Piscirickettsiaceae/imunologia , Distribuição Aleatória , Baço/imunologia , Baço/microbiologia , Fatores de TempoRESUMO
OBJECTIVE: To identify relevant relative cerebral blood volume biomarkers from T2* dynamic-susceptibility contrast magnetic resonance imaging to anticipate glioblastoma progression after chemoradiation. METHODS: Twenty-five patients from a prospective study with glioblastoma, primarily treated by chemoradiation, were included. According to the last follow-up MRI confirmed status, patients were divided into: relapse group (n = 13) and control group (n = 12). The time of last MR acquisition was tend; MR acquisitions performed at tend-2M, tend-4M and tend-6M (respectively 2, 4 and 6 months before tend) were analyzed to extract relevant variations among eleven perfusion biomarkers (B). These variations were assessed through R(B), as the absolute value of the ratio between ∆B from tend-4M to tend-2M and ∆B from tend-6M to tend-4M. The optimal cut-off for R(B) was determined using receiver-operating-characteristic curve analysis. RESULTS: The fraction of hypoperfused tumor volume (F_hPg) was a relevant biomarker. A ratio R(F_hPg) ≥ 0.61 would have been able to anticipate relapse at the next follow-up with a sensitivity/specificity/accuracy of 92.3 %/63.6 %/79.2 %. High R(F_hPg) (≥0.61) was associated with more relapse at tend compared to low R(F_hPg) (75 % vs 12.5 %, p = 0.008). CONCLUSION: Iterative analysis of F_hPg from consecutive examinations could provide surrogate markers to predict progression at the next follow-up. KEY POINTS: ⢠Related rCBV biomarkers from DSC were assessed to anticipate GBM progression. ⢠Biomarkers were assessed through their patterns of variation during the follow-up. ⢠The fraction of hypoperfused tumour volume (F_hP g ) seemed to be a relevant biomarker. ⢠An innovative ratio R(F_hP g ) could be an early surrogate marker of relapse. ⢠A significant time gain could be achieved in the management of GBM patients.
Assuntos
Biomarcadores/metabolismo , Neoplasias Encefálicas/terapia , Quimiorradioterapia/métodos , Glioblastoma/terapia , Adulto , Idoso , Volume Sanguíneo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Meios de Contraste , Progressão da Doença , Feminino , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estudos Prospectivos , Curva ROCRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Solanum sisymbriifolium Lam., is used in Paraguayan folk medicine claiming antihypertensive and diuretic properties. AIM OF THE STUDY: This study aimed to determine the influence of chronic oral administration of the crude root extract and saponins obtained from S. sisymbriifolium Lam., on the blood pressure of male and female rats with hypertension induced by L-NAME, and its consequences on diuresis, the body weight, blood glucose, and level of serum parameters of liver and kidney functionality. MATERIALS AND METHODS: Wistar rats were randomly divided into seven male, and seven female groups (8 animals each), which received as 6-week pretreatment, 0.9% saline solution (two groups; 0.1mL/10 g of b.w.), L-arginine (100.0 mg/kg/day), enalapril (15.0 mg/kg/day), crude extract (CESs 100.0 mg/kg/day), and saponin purified fraction (1.0, and 10.0 mg/kg/day), and treated with L-NAME (20 mg/kg/day/i.p.) twice, 1, and 6 h after pre-treatment. The animals' body weight, glycemia, and blood pressure were recorded weekly, while serum, hepatic, renal, and histological parameters were analyzed at the end of 6-week of treatment. RESULTS: A protective effect of CESs (100.0 mg/kg/day), and saponins (1.0, and 10.0 mg/kg/day) against hypertension induced by L-NAME was verified in the systolic, diastolic, and mean blood pressure values, which were significantly lower than the positive L-NAME-hypertensive control group (male and female) at the end of the 6-week treatment. Also, pretreatment with enalapril (15.0 mg/kg/day) induced an efficient protective activity, which validates the method used. Likewise, the volume of urine, creatinine, uric acid, urea, and electrolyte excretion was enhanced at the end of 6-week of treatment in concordance with the reduction in serum level of the same parameters, compatible with the improvement of the diuretic activity. The glycemia, body weight, heart rate, and functional hepato-renal parameters were not modified after a 6-week of treatment, in comparison to the control group, indicating relatively acceptable harmless properties of CESs and saponins. Interestingly, the HDL level in females was increased in contrast to male rats by chronic saponins treatment when compared with the negative control group. CONCLUSIONS: It can be concluded that either the increment in blood pressure (systolic, diastolic, and median) or cardiorenal remodeling effects in male and female rats submitted to L-NAME-induced hypertensive condition, were prevented and well-preserved without a significant variation during a period of 6-week of pretreatment with CESs and saponins pretreatments. Likewise, an important diuretic effect was revealed after this period of treatment.
Assuntos
Hipertensão , Saponinas , Solanum , Animais , Anti-Hipertensivos , Pressão Sanguínea , Peso Corporal , Diuréticos/farmacologia , Enalapril , Feminino , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Extratos Vegetais , Ratos , Ratos Wistar , Saponinas/farmacologia , Saponinas/uso terapêuticoRESUMO
The aim of the present work is to demonstrate the putative sedative and anxiolytic-like effects of a hydro-ethanolic extract obtained from the aerial parts of Aloysia polystachya (Verbenaceae) in male mice using several behavioural assays. Groups of male mice orally treated with doses of 1.0, 10.0 and 100.0 mg/kg of the extract did not show any significant alteration of their locomotor activity, body temperature or motor coordination. The same treatment increased the duration of the sleeping time induced by 30.0 mg/kg i.p. of sodium pentobarbital. However, the sleeping time induced by ethyl ether was not modified by the oral administration of the extract, not confirming the putative sedative effect of the plant. The ethanolic extract also significantly increased the percentage of both entries (1.0 and 100.0 mg/kg) and the time spent (10.0 and 100.0 mg/kg) into the open arms of the elevated plus maze (EPM). Nevertheless, the binding of (3)H-flunitrazepam ((3)H-FNZ) to the benzodiazepine binding site (BDZ-bs), in washed crude synaptosomal membranes from rat cerebral cortex, was not affected by the semi-purified components from Aloysia polystachya. These results indicate an anxiolytic-like profile of action for the extract of Aloysia polystachya without sedative side effect, being this activity probably mediated by other mechanism than BDZ-bs modulation at the GABA(A) receptors.
Assuntos
Ansiolíticos/farmacologia , Extratos Vegetais/farmacologia , Verbenaceae , Animais , Comportamento Animal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Flunitrazepam/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Sono/efeitos dos fármacosRESUMO
ETHNO-PHARMACOLOGICAL RELEVANCE: Kyllinga brevifolia rhizomes (Cyperaceae) are used in Paraguayan traditional medicine as a refreshing beverage, and is claimed to own digestive, diuretic, sedative, tonic, antispasmodic and sudorific properties. We have previously reported that its hydro- ethanolic rhizome extract possess sedative, anxiolytic and anti-aggressive-like effects in mice. However, information on its potential for treatment of syndromes associated with mood disorders is scarce. AIM OF THE STUDY: The purpose of this study is to characterize the putative antidepressant-like effects of the hydro-ethanolic extract (CEKb) and the ethyl acetate fraction (KbF-ethyl-ac) obtained from the rhizome of K. brevifolia (Rottb) on male mice exposed to forced swimming test. Also, chemical characterization of the components of the active ethyl acetate fraction was described. MATERIALS AND METHODS: The antidepressant-like effects of CEKb and KbF-ethyl-ac were measured using the forced swimming test (FST) performance of male mice in single (acute), short-term and chronic modalities. Treatments in all modalities were made 1h before swimming test. The KbF-ethyl-ac was analyzed by LC-DAD-ESI-MS and LC-ESI-MS/MS in order to identify the active components. RESULTS: A single doses (1.0, 10.0 and 100.0mg/kg, p.o; p<0.05) of CEKb, in male mice provoked a significant reduction of the immobility time. Such effect was also observed with oral short-term treatment (7 days) with doses of 10.0 and 100.0mg/kg/day (p<0.05) of CEKb. Moreover, in the treatments during 14 days with doses of 1.0 (p<0.05), 10.0 (p<0.05), and 100.0 (p<0.001) mg/kg, p.o, of CEKb, a statistically significant reduction of the immobility time were induced. Additionally, in a different set of experiments acute dose of 1.0 (p<0.05) and 10.0 (p<0.01) mg/kg, p.o, of KbF-ethyl-ac in male mice, a significant reduction of the immobility time were provoked. Likewise, short-term treatment (7 days) with 1.0, and 10.0mg/kg (p<0.05); and after 14 days of treatment with 0.01 (p<0.01) 0.1 (p<0.001), 1.0 (p<0.001), and 10.0 (p<0.05) mg/kg of KbF-ethyl-ac in male mice, a statistically significant reduction of the immobility time, were observed. Imipramine 32mg/kg/days, i.p, induced a statistically significant reduction of immobility time and was used as positive control to validate the method employed. Moreover, it was noted important differences in the onset of the antidepressant-like effect in the FST, depending on the modality of treatment with CEKb or KbF-ethyl-ac (acute, short-term or chronic). Both, efficacy and potency were higher when repeated administration of CEKb was used, and surprisingly the efficacy of 1.0mg/kg of KbF-ethyl-ac (14 days) was similar to imipramine. The main constituents of the KbF-ethyl-ac were identified as catechins and their dimers by LC-DAD-ESI-MS and LC-ESI-MS/MS, according to their UV and MS spectra, as compared with the literature data. These results indicate an important antidepressant-like profile of action for the CEKb and KbF-ethyl-ac; and meanwhile, this effect may partially reside on catechins and their dimers isolated from the KbF-ethyl-ac. CONCLUSION: These findings indicate that K. brevifolia exerts antidepressant -like effects in mice and suggest its potential usefulness for the treatment of depression in humans and encourage us to pursue the isolation of the molecules associated to the effect observed in CEKb and KbF-ethyl-ac, and to determine the mechanism of antidepressant-like effect of Kyllinga brevifolia using adequate complementary test.
Assuntos
Acetatos/química , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Extratos Vegetais/farmacologia , Rizoma/química , Animais , Antidepressivos/química , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/química , Natação/fisiologiaRESUMO
Isonuatigenin-3-O-beta-solatriose (1) was isolated from the roots of Solanum sisymbriifolium. Its structure was determined by spectroscopic methods.
Assuntos
Fitoterapia , Extratos Vegetais/química , Solanum , Humanos , Estrutura Molecular , Raízes de Plantas , Saponinas/químicaRESUMO
The purpose of the present study was to evaluate in vivo the effect of a non competitive antagonist of the NMDA receptor, eliprodil, on the size of a focal ischaemic insult and on its temporal evolution in a rat model, using a spin-echo diffusion magnetic resonance imaging multislice technique. Rats were either injected with 1 mg/kg i.v. of eliprodil or with the vehicle only (placebo) 5 min after middle cerebral artery occlusion, or not injected (controls). Ten coronal slices were acquired every hour, up to 7 h after occlusion of the artery, and the volume of hyperintense signals was measured at each time point and for each animal. Diffusion magnetic resonance images revealed that the administration of eliprodil reduced significantly (by 50% or more) the volume of ischaemia, up to 7 h after occlusion, particularly in the cortex of the ipsilateral hemisphere. The results show the potential efficacy of eliprodil to reduce the cerebral ischaemic volume after arterial occlusion, thus confirming the interest of glutamate receptor antagonists in the treatment of ischaemia.
Assuntos
Isquemia Encefálica/patologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Piperidinas/farmacologia , Animais , Isquemia Encefálica/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Radiografia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidoresRESUMO
OBJECTIVE: In our multidisciplinary pain clinic, three patients with amputated limbs and with surgical indications for chronic motor cortex stimulation for phantom limb pain were selected for their ability to voluntarily move the missing limb. The sensation of being able to move a missing limb at will occurs quite frequently among traumatic amputees, but the ability to control it sufficiently to perform a functional magnetic resonance imaging (fMRI) examination is more rarely encountered. We used motor fMRI to study these virtual movements. METHODS: In two patients with upper-limb amputations, movements of the stump, the normal hand, and the missing arm were studied. In a third patient with both legs amputated, movements of the stumps and of the missing feet were studied. The fMRI data were analyzed with the Statistical Parametric Map 96 software and reformatted for integration into anatomic slices. RESULTS: Virtual movements of the missing limbs produced contralateral primary sensorimotor cortex and central sulcus activations in the patients with upper-limb amputation. Interhemispheric and bilateral activations were found in the patient with both legs amputated. These activation areas were different from the stump activation areas. Additionally, the significance thresholds chosen to generate the activation maps in virtual movements (although individual) were globally the same as those used to detect motor activation in the normal side of the patients. CONCLUSION: Cortical areas devoted to the missing limb seem to persist for several years after amputation. The precentral activations found in our patients are in agreement with the statement that the neural mechanisms involved in the mental representation of an action and in its execution are the same. Data from fMRI can be used to evaluate phantom limb virtual movements and to study cortical reorganization phenomena that can appear with time or as a result of some therapies. In these patients, fMRI data may be useful in assisting the neurosurgeon in the placement of chronic motor cortex electrodes.
Assuntos
Amputados , Córtex Motor/fisiologia , Movimento/fisiologia , Córtex Somatossensorial/fisiologia , Interface Usuário-Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/anatomia & histologia , Limiar Sensorial/fisiologia , Córtex Somatossensorial/anatomia & histologiaRESUMO
OBJECTIVE AND IMPORTANCE: Chronic motor cortex stimulation has provided satisfactory control of pain in patients with central or neuropathic trigeminal pain. We used this technique in a patient who experienced phantom limb pain. Functional magnetic resonance imaging (fMRI) was used to guide electrode placement and to assist in understanding the control mechanisms involved in phantom limb pain. CLINICAL PRESENTATION: A 45-year-old man whose right arm had been amputated 2 years previously experienced phantom limb pain and phantom limb phenomena, described as the apparent possibility of moving the amputated hand voluntarily. He was treated with chronic motor cortex stimulation. INTERVENTION: Data from fMRI were used pre- and postoperatively to detect shoulder and stump cortical activated areas and the "virtual" amputated hand cortical area. These sites of preoperative fMRI activation were integrated in an infrared-based frameless stereotactic device for surgical planning. Phantom limb virtual finger movement caused contralateral primary motor cortex activation. Satisfactory pain control was obtained; a 70% reduction in the phantom limb pain was achieved on a visual analog scale. Postoperatively and under chronic stimulation, inhibiting effects on the primary sensorimotor cortex as well as on the contralateral primary motor and sensitive cortices were detected by fMRI studies. CONCLUSION: Chronic motor cortex stimulation can be used to relieve phantom limb pain and phantom limb phenomena. Integrated by an infrared-based frameless stereotactic device, fMRI data are useful in assisting the neurosurgeon in electrode placement for this indication. Pain control mechanisms and cortical reorganization phenomena can be studied by the use of fMRI.
Assuntos
Terapia por Estimulação Elétrica/métodos , Membro Fantasma/terapia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/anatomia & histologia , Córtex Motor/fisiologiaRESUMO
OBJECTIVE: The aim of this article was to analyze the technical and methodological issues resulting from the use of functional magnetic resonance image (fMRI) data in a frameless stereotactic device for brain tumor or pain surgery (chronic motor cortex stimulation). METHODS: A total of 32 candidates, 26 for brain tumor surgery and six chronic motor cortex stimulation, were studied by fMRI scanning (61 procedures) and intraoperative cortical brain mapping under general anesthesia. The fMRI data obtained were analyzed with the Statistical Parametric Mapping 99 software, with an initial analysis threshold corresponding to P < 0.001. Subsequently, the fMRI data were registered in a frameless stereotactic neuronavigational device and correlated to brain mapping. RESULTS: Correspondence between fMRI-activated areas and cortical mapping in primary motor areas was good in 28 patients (87%), although fMRI-activated areas were highly dependent on the choice of paradigms and analysis thresholds. Primary sensory- and secondary motor-activated areas were not correlated to cortical brain mapping. Functional mislocalization as a result of insufficient correction of the echo-planar distortion was identified in four patients (13%). Analysis thresholds (from P < 0.0001 to P < 10(-12)) more restrictive than the initial threshold (P < 0.001) had to be used in 25 of the 28 patients studied, so that fMRI motor data could be matched to cortical mapping spatial data. These analysis thresholds were not predictable preoperatively. Maximal tumor resection was accomplished in all patients with brain tumors. Chronic motor cortex electrode placement was successful in each patient (significant pain relief >50% on the visual analog pain scale). CONCLUSION: In brain tumor surgery, fMRI data are helpful in surgical planning and guiding intraoperative brain mapping. The registration of fMRI data in anatomic slices or in the frameless stereotactic neuronavigational device, however, remained a potential source of functional mislocalization. Electrode placement for chronic motor cortex stimulation is a good indication to use fMRI data registered in a neuronavigational system and could replace somatosensory evoked potentials in detection of the central sulcus.
Assuntos
Neoplasias Encefálicas/cirurgia , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Imageamento por Ressonância Magnética/métodos , Córtex Motor/cirurgia , Dor/cirurgia , Técnicas Estereotáxicas , Cirurgia Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Mapeamento Encefálico , Neoplasias Encefálicas/diagnóstico , Doença Crônica , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-IdadeRESUMO
The delay in the appearance and the extent of a lesion induced by gamma-irradiation, in rabbit iliospinalis muscles, have been evaluated in vivo by MRI. The left side rabbit muscle was irradiated with an 192Ir sealed source at two skin surface doses: 40 Gy and 80 Gy. The progress of the lesion was followed on a long-term basis (12 months) by using T2 weighted spin echo imaging. The irradiation induced lesions were detected by MRI 22 weeks after irradiation for the 40 Gy group and 17 weeks for the 80 Gy group. The atrophy of the muscle and the extent of the lesion increased as a function of the dose at the skin surface. The threshold depth dose, corresponding to the deepest border of the lesion, was calculated by using the monoexponential attenuation law. The results gave the value of 20 +/- 7 Gy for the 40 Gy group and 16 +/- 3 Gy for the 80 Gy group.
Assuntos
Imageamento por Ressonância Magnética , Músculo Esquelético/efeitos da radiação , Lesões por Radiação/diagnóstico , Animais , Atrofia/diagnóstico , Atrofia/etiologia , Relação Dose-Resposta à Radiação , Feminino , Raios gama , Músculo Esquelético/patologia , Coelhos , Doses de Radiação , Pele/efeitos da radiação , Fatores de TempoRESUMO
Acute toxicity and general pharmacological activities of the crude hydro-alcoholic rhizome extract of Kyllinga brevifolia Rottb., a popular medicine used in Paraguay, were investigated on mice. The intraperitoneal LD50 was found to be 575 mg/kg. Oral administration of doses up to 3.0 g/kg did not provoke any toxic symptoms. Oral administration of 100 mg/kg of the extract induced a significant increase in gastrointestinal transit. In open field studies, a decrease of spontaneous locomotor activity, piloerection, passivity, palpebral ptosis, catatonia and a stereotyped behaviour was produced by the extract when administered orally (1, 10 and 100 mg/kg). A significant decrease in respiration rate was observed (1, 10 and 100 mg/kg, p.o.) using a continuous flow respiration system. Lastly, doses of 1, 10 and 100 mg/kg, p.o. of the extract produced a significant increase in the hypnotic effect induced by pentobarbital in a dose-dependent manner. The latest effects could probably explain its rational use in traditional medicine to alleviate stress or as a sedative agent.
Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Trânsito Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Paraguai , Pentobarbital/farmacologia , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Plantas Medicinais/química , Respiração/efeitos dos fármacos , Sono/efeitos dos fármacos , Fatores de TempoRESUMO
The hypotensive effect of the crude hydroalcoholic extract from root of Solanum sisymbriifolium Lam. (Solanaceae) was investigated both in normotensive and hypertensive rats. The intravenous administration of the extract (50 and 100 mg/kg) produced a significant decrease in blood pressure in anaesthetized hypertensive (adrenal regeneration hypertension + deoxycorticosterone acetate (ARH + DOCA)) rats. Oral administration of the extract (10, 50, 100 and 250 mg/kg) also produced a dose-dependent hypotensive effect in conscious hypertensive animals. In anaesthetized normotensive rats, the extract (50 and 100 mg/kg, i.v.) also induced hypotension in a dose-dependent manner. Lastly, no significant effect on blood pressure was produced by the extract when administered orally (10, 50, 100, 250, 500 and 1000 mg/kg) to conscious normotensive rats.
Assuntos
Anti-Hipertensivos/farmacologia , Extratos Vegetais/farmacologia , Raízes de Plantas/metabolismo , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Desoxicorticosterona/administração & dosagem , Desoxicorticosterona/toxicidade , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Injeções Intravenosas , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ratos , Ratos WistarRESUMO
Early imaging investigations in multiple sclerosis (MS) described focal signs. Technological progress now suggests this concept should be revisited as more diffuse anomalies of the central nervous system are described, sometimes involving regions that appear normal with conventional imaging techniques. This integrative concept results largely from the contribution of magnetic resonance imaging techniques recently broadened to in vivo investigations. Technical developments in MRI now provide new contrast images (magnetization transfer, diffusion, anisotropic diffusion, functional MRI using the BOLD method) as well as new variants of conventional sequences designed to demonstrate specific aspects of the MS lesions: FLAIR sequence (a T2-weighted sequence), black holes (a particular aspect on T1-weighted images), cord atrophy (quantification of the axial section of the cord on T1-weighted sequences). Together these new methods should improve diagnostic sensitivity (FLAIR) or provide prognosis information not provided by conventional sequences (T2 or T2 weighted images with or without gadolinium injection).
Assuntos
Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico , Encéfalo/patologia , Seguimentos , Humanos , Sensibilidade e Especificidade , Medula Espinal/patologiaRESUMO
Magnetic resonance spectroscopy (MRS) is a tool for a non-invasive monitoring of brain tumor metabolism. In vivo proton MRS became possible with the development of whole-body high-field magnets. First, it allows to distinguish brain tumors from abscesses. Second, along with other imaging techniques, it permits the differentiation of primary brain tumors, mainly gliomas, from tumors of various origins such as meningiomas or metastasis. However, its ability to give a grading of gliomas stays controversial. Choline, a marker of cell membrane proliferation, could give information on the degree of malignancy but reports on its role are somewhat contradictory. Brain tumor biopsy and histology stay mandatory in the management of brain tumors. In vitro MRS spectra obtained from tumor extracts show that the signal at 3.2ppm, the so-called "cholin peak", corresponds to several compounds among them, glycerophosphocholine, phosphocholine, and choline. Their repartition differs with the grade of the tumor. In vivo proton MRS is the only metabolic technique of non-invasive monitoring of treated brain tumors. It can separate recurrence from radionecrosis. Improved methodology and availability of MR imagers will strengthen its importance in the future.
Assuntos
Ácido Aspártico/análogos & derivados , Neoplasias Encefálicas/diagnóstico , Metabolismo Energético/fisiologia , Glioma/diagnóstico , Espectroscopia de Ressonância Magnética , Ácido Aspártico/metabolismo , Biópsia , Encéfalo/patologia , Encéfalo/fisiopatologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/secundário , Colina/metabolismo , Diagnóstico Diferencial , Glioma/fisiopatologia , Humanos , Valor Preditivo dos Testes , PrognósticoRESUMO
UNLABELLED: This chapter describes and discusses the value of the localization of functional areas obtained from functional MRI in brain tumor cases. Correlation method is cortical brain mapping by intraoperative stimulation. The experience reported here is focused on the study of motricity and language. METHODS: Twenty two patients with tumors of the rolandic region (n = 16) or in the temporal lobe (n = 6) underwent functional MR mapping and subsequently cortical mapping before tumor resection. The tasks chosen were a flexion and extension of the fingers or a naming task. We used 3D reconstructed images of the surface of the brain to assess intra and post operatively the functional MRI and stimulation data. RESULTS: For the motor correlation, in each case, the results of direct cortical mapping matched those obtained with functional MRI, both positively and negatively, although the extent of the functional activations was larger than the area required to elicit the corresponding movement during intraoperative brain mapping. For the language correlation and for the task chosen, only the results of the precentral areas matched those of functional MRI. CONCLUSIONS: Functional MRI can be used preoperatively to assess motor functional area in patients with rolandic tumors. More studies are needed to validate intraoperatively the language areas and the real extent of functional MRI activations. Finally, the observed discrepancy between functional MRI and cortical stimulation is likely due to the rather profound differences between both techniques, in terms of neurophysiology, practical applications and statistical analysis.
Assuntos
Neoplasias Encefálicas/diagnóstico , Cuidados Intraoperatórios/métodos , Idioma , Imageamento por Ressonância Magnética/métodos , Atividade Motora/fisiologia , Adulto , Idoso , Neoplasias Encefálicas/cirurgia , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
INTRODUCTION: Since its description in the early 1990's, functional magnetic resonance imaging (fMRI) has been used first for research purposes, and after in clinical applications in the field of neurosurgery. The purpose of this article was to critically review the literature on fMRI to achieve a better understanding of the usefulness of fMRI in brain surgery for tumors, epilepsy surgery, and radiosurgery. MATERIAL AND METHODS: Medical literature databases containing peer-review articles dating from 1990 were queried for key words related to fMRI. RESULTS: On 3,065 references scanned for relevance, 256 articles with direct or indirect relationships between fMRI and neurosurgery were analyzed. DISCUSSION: fMRI can be useful in the selection of patients for whom a surgical resection is attempted and could aid in the decision-making whether to operate on a patient who has been previously considered inoperable. fMRI is a useful tool in the decisional scheme of treatment of low-grade astrocytomas or arteriovenous malformations in the rolandic area in intact or slightly impaired patients. fMRI can be repeated in selected patients with slow growing brain tumors or congenital lesions such as AVM to study cortical reorganization phenomena. In epilepsy surgery, the Wada-test could be substituted by fMRI to determine the hemispheric dominance of language. The choice of standardized tasks and a better understanding of analysis problems in the treatment of fMRI images must be achieved before drawing more accurate conclusions on fMRI and brain tumors.
Assuntos
Encefalopatias/patologia , Encefalopatias/cirurgia , Imageamento por Ressonância Magnética , Encefalopatias/fisiopatologia , HumanosRESUMO
AIMS: Intramyocellular lipid (IMCL) variations in older men are poorly explored. In young adults, IMCL can be influenced by both diet and exercise interventions; this flexibility is related to aerobic fitness. We evaluated in active older adults the influence of maximal aerobic capacity on short-term diet and exercise-induced variations in IMCL stores. METHODS: Intramyocellular lipids were measured by (1) H magnetic resonance spectroscopy ((1) H-MRS) after a 3-day fat depletion-replenishment diet (IMCL(FDR) ) and immediately after a 2-h exercise at 50% VO(2) max (IMCL(FDR) (_) (EX) ). To further explore diet influence, the protocol was repeated after a high-fat diet (HF), with both pre- and post-exercise measurements (IMCL(HF) and IMCL(HF) (_) (EX) ). RESULTS: In active older men (69.8 ± 5.2 years), IMCL(FDR) was lowered by exercise (IMCL(FDR) = 3.45 ± 1.52 vs. IMCL(FDR) (_) (EX) = 2.74 ± 1.15 mmol kg(-1) wet weight, P < 0.05), and exercise-induced variations were correlated to the initial store (P < 0.05, r = -0.72). IMCL(FDR) was linked with aerobic fitness (P < 0.05, r = 0.76), when adjusted by fat mass. IMCL(HF) was lower than IMCL(FDR) (P < 0.05), decreased after exercise (P < 0.05) and varied also as a function of initial store (P < 0.05, r = -0.89), but without link with aerobic fitness. Finally, diet-induced IMCL store variations were positively linked to aerobic fitness (P < 0.05, r = 0.89). CONCLUSION: Variations of the IMCL stores in physically active older adults appear related to aerobic fitness, with similarly fast adaptation to short-term interventions combining diet and exercise as young active adults.
Assuntos
Envelhecimento/metabolismo , Gorduras na Dieta/metabolismo , Músculo Esquelético/metabolismo , Aptidão Física , Adaptação Fisiológica , Fatores Etários , Idoso , Análise de Variância , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Gorduras na Dieta/administração & dosagem , Teste de Esforço , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Consumo de Oxigênio , Fatores Sexuais , Fatores de TempoRESUMO
BACKGROUND AND PURPOSE: MS is an inflammatory demyelinating disease affecting both WM and GM. While WM lesions are easily visualized by conventional MR imaging, the detection of GM alterations remains challenging. This diffusion tensor MR imaging study aimed to detect and characterize diffuse microscopic alterations in 2 deep GM structures, the caudate nucleus and the thalamus, in patients with RR and SP MS. The relationship between diffusivity markers, and atrophy of the caudate and the thalamus, as well as brain lesion load and clinical status of the patients was also explored. MATERIALS AND METHODS: Twenty-three RR and 18 SP patients, along with 27 healthy controls, underwent MR imaging examination including anatomic and DTI acquisitions. Volumes, mean FA, and MD of the caudate and the thalamus, as well as WM lesion volumes, were assessed. RESULTS: FA was significantly (P < .001) increased in the caudate and the thalamus of patients with MS compared with controls, and was higher in SP compared with RR patients. Increased FA was associated with volume decreases of caudate (r = -0.712; P < .001) and thalamus (r = -0.407; P < .01) in patients with MS. WM T2 lesion load was significantly associated with caudate (r = 0.611; P < .001) and thalamic (r = 0.354; P < .05) FA. Caudate FA, and, to a lesser extent, thalamic FA, were associated with functional deficits, as measured by EDSS and MSFC. CONCLUSIONS: Increased FA in the caudate and the thalamus may constitute a sensitive marker of MS pathologic processes, such as loss of dendrites and/or swelling of neuronal cell bodies.
Assuntos
Núcleo Caudado/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Esclerose Múltipla/patologia , Neurônios/patologia , Núcleos Talâmicos/patologia , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The aim of the study is to assess the hypotensive properties of the hydro-ethanolic crude root extract (CRE), the n-butanol fraction (F(BtOH)) and nuatigenin-3-O-ß-chacotriose, from Solanum sisymbriifolium Lam., in adrenal regeneration hypertension+deoxycorticosterone acetate (ARH+DOCA) rats, following a chronic administration. The roots of S. sisymbriifolium Lam. (Solanaceae) were extracted by reflux with ethanol-water 7:3 and the active extract was fractionated by bioassay-guided liquid-liquid separation. Nuatigenin-3-O-ß-chacotriose (B(3-1)) was identified as the main hypotensive compound from the crude drug by spectroscopic methods. Immature Wistar rats of both sexes were submitted to both surgery and deoxycorticosterone acetate treatment to obtain adrenal regeneration hypertensive rats (ARH+DOCA). Different groups of experimentally induced hypertensive rats were randomly allotted and received during 16 weeks a daily oral administration of 1% saline solution (0.1 mL/100g body weigh), 100.0 mg/kg of CRE, 10.0, 30.0 and 50.0 mg/kg of F(BtOH), and 1.0 mg/kg of B(3-1), respectively. In addition, two groups of ARH+DOCA rats were randomly assigned to receive either B(3-1) (1.0 mg/kg/day) or 1% of saline solution (0.1 mL/100g body weight/day) for 7 weeks and then a cross over procedure was performed in order to complete the 16th-week treatment. After 16 weeks of oral administration of crude root extract (CRE), butanolic fraction (F(BtOH)) and nuatigenin-3-O-ß-chacotriose (B(3-1)) a significant reduction of blood pressure value was induced in hypertensive animals (ARH+DOCA) in comparison to the control group receiving 1% saline solution, at the end of experiment. Administration of B(3-1) (1.0 mg/kg/day p.o.) to ARH+DOCA rats provoked a significant reduction of blood pressure, observed gradually from 5th week (p<0.05) to the end of the 16th week period of treatment (p<0.01). Moreover, in a cross over design it was observed that the reduction of blood pressure to normotensive condition is associated to B(3-1). The latest demonstrated that the blood pressure-lowering effect, in clearly hypertensive animals, is reversible and depend upon administration of nuatigenin-3-O-ß-chacotriose (B(3-1)). Our results demonstrated that daily oral administration of CRE, F(BtOH) and nuatigenin-3-O-ß-chacotriose from S. sisymbriifolium for a 16-week period exhibits an antihypertensive effect in experimentally hypertensive (ARH+DOCA) rats.