RESUMO
Spinocerebellar ataxia type 3 (SCA3) is the most frequent inherited cerebellar ataxia in Europe, the US and Japan, leading to disability and death through motor complications. Although the affected protein ataxin-3 is found ubiquitously in the brain, grey matter atrophy is predominant in the cerebellum and the brainstem. White matter pathology is generally less severe and thought to occur in the brainstem, spinal cord, and cerebellar white matter. Here, we investigated both grey and white matter pathology in a group of 12 SCA3 patients and matched controls. We used voxel-based morphometry for analysis of tissue loss, and tract-based spatial statistics (TBSS) on diffusion magnetic resonance imaging to investigate microstructural pathology. We analysed correlations between microstructural properties of the brain and ataxia severity, as measured by the Scale for the Assessment and Rating of Ataxia (SARA) score. SCA3 patients exhibited significant loss of both grey and white matter in the cerebellar hemispheres, brainstem including pons and in lateral thalamus. On between-group analysis, TBSS detected widespread microstructural white matter pathology in the cerebellum, brainstem, and bilaterally in thalamus and the cerebral hemispheres. Furthermore, fractional anisotropy in a white matter network comprising frontal, thalamic, brainstem and left cerebellar white matter strongly and negatively correlated with SARA ataxia scores. Tractography identified the thalamic white matter thus implicated as belonging to ventrolateral thalamus. Disruption of white matter integrity in patients suffering from SCA3 is more widespread than previously thought. Moreover, our data provide evidence that microstructural white matter changes in SCA3 are strongly related to the clinical severity of ataxia symptoms.
Assuntos
Encéfalo/patologia , Doença de Machado-Joseph/patologia , Adulto , Anisotropia , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Doença de Machado-Joseph/genética , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/etiologia , Análise de Regressão , Medula Espinal/patologia , Tálamo/patologiaRESUMO
The bio-optical compact disk (BioCD) is an optical biosensor that performs common-path molecular interferometry of patterned proteins on a disk spinning at high speed. The common-path configuration makes it ultrastable and allows surface height precision below 10 pm. In this paper we show that two complementary interferometric quadrature conditions exist simultaneously that convert the modulus and phase of the reflection coefficient, modulated by protein patterns on the disk surface, into intensity modulation at the detector. In the far field they separate into spatially symmetric and antisymmetric intensity modulation in response to the local distribution of protein. The antisymmetric response is equivalent to differential phase-contrast detection, and the symmetric response is equivalent to in-line (IL) common-path interferometry. We measure the relative sensitivities of these orthogonal channels to printed protein patterns on disk structures that include thermal oxide on silicon and Bragg dielectric stacks. The scaling mass sensitivity of the IL channel on oxide on silicon was measured to be 0.17 pg/mm.
RESUMO
Colorectal cancers exhibit a red fluorescence. The nature of the responsible fluorophore and its eventual diagnostic potential were investigated. Thirty-three consecutive colorectal resection specimen, 32 of which with histologically confirmed cancer, and a total of 1053 palpable mesenteric nodes were fluorimetrically characterized ex vivo. Furthermore, frozen material from 28 patients was analyzed, selected for the availability of primary tumor material and metastatic tissue, e.g., lymphatic and liver metastases from the same patient. Biochemical characterization was carried out through chemical extraction and reversed phase high-performance liquid chromatography. The fluorescence spectra of tissues, tissue extracts, and standard solutions of porphyrins were determined using a pulsed solid-state laser system for excitation and an imaging polychromator, together with an intensified CCD camera for time-delayed observation. Protoporphyrin IX (PpIX) was identified as the predominant fluorophore in primary tumors and their metastases. The fluorophore occurred in the absence of necrosis and in sterile locations. In untreated cases (n = 24), PpIX fluorescence discriminates metastatically involved lymph nodes from all other palpable nodes with a sensitivity of 62% at a specificity of 78% (P < 0.0001). After neoadjuvant treatment of rectal cancer, the PpIX fluorescence level of the primary tumors was reduced and a discrimination of lymph nodes based on PpIX-fluorescence was impossible. We conclude that colorectal cancer metastases accumulate diagnostic levels of endogenous PpIX as a result of a tumor-specific metabolic alteration.
Assuntos
Neoplasias Colorretais/metabolismo , Protoporfirinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Humanos , Hipertermia Induzida , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Especificidade de Órgãos , Espectrometria de FluorescênciaRESUMO
The effect of hyperbaric oxygen (HBO) at 2.5 atmospheres of absolute pressure (ATA) on postischemic reperfusion injury in striated muscle was studied using two different animal models. One used complete tourniquet ischemia (4 hr) in the rat hindlimb, measuring blood flow in the tibialis anterior muscle by the xenon washout method at 1-1.5 and 4.5-5 hr after the start of reperfusion. The other used 4 hr of pressure-induced ischemia in the fine striated skin muscle, contained within a dorsal skinfold chamber in hamsters. Vital fluorescence microscopy was employed to measure the functional capillary density using fluorescein isothiocyanate-dextran (mw 150,000) as a plasma marker. After 1-1.5 hr of reperfusion following 4 hr of total ischemia, postischemic blood flow was severely depressed, with no significant difference between the HBO-treated and the untreated rats. However, after 4.5-5 hr of reperfusion, blood flow rates in the postischemic muscle in the HBO-treated animals did not differ significantly from those in nonischemic muscle, compared to a persistent, significant depression in the untreated animals. No significant difference was seen in functional capillary density between HBO-treated and untreated hamsters following 1 hr of reperfusion. After 5 hr of reperfusion, capillary density was significantly improved in HBO-treated animals compared to untreated animals. These results suggest that HBO treatment enhances the recovery of blood flow and functional capillary density in postischemic muscle tissue, indicating attenuation of the microvascular dysfunction or damage in the postischemic period.
Assuntos
Oxigenoterapia Hiperbárica , Isquemia/terapia , Traumatismo por Reperfusão/prevenção & controle , Animais , Cricetinae , Dextranos , Modelos Animais de Doenças , Fluoresceína-5-Isotiocianato , Membro Posterior , Masculino , Mesocricetus , Músculos/irrigação sanguínea , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , XenônioRESUMO
We investigated whether the odor of garlic can cross the placental barrier from the mother to the fetal environment. Samples of amniotic fluid, allantoic fluid, fetal blood, and maternal blood were collected 0, 50, 100, and 150 min after a pregnant ewe (approximately day 110 of gestation) was gavaged with 6 ml of Egyptian garlic oil. A panel of judges detected (p < 0.05) garlic odor in samples of allantoic fluid, fetal blood, and maternal blood collected 50, 100, and 150 min after the ewe was given garlic and in samples of amniotic fluid collected 100 min after treatment.
Assuntos
Alho , Troca Materno-Fetal/fisiologia , Plantas Medicinais , Prenhez/fisiologia , Olfato/fisiologia , Paladar/fisiologia , Animais , Feminino , Idade Gestacional , Gravidez , OvinosRESUMO
BACKGROUND: In vitro and in vivo experiments have demonstrated the role of oxidatively modified low density lipoprotein (oxLDL) in eliciting leukocyte/endothelium interaction during early atherogenesis. METHODS AND RESULTS: In the present study we investigated the effect of dietary fish oil on oxLDL-induced leukocyte/endothelium interaction using intravital fluorescence microscopy in the dorsal skinfold chamber model in awake Syrian golden hamsters. Hamsters were fed for 4 weeks prior to the experiments with either standard laboratory chow or a diet supplemented with 5% of a fish oil concentrate (18% eicosapentaenoate, 12% docosahexaenoate). The efficacy of the fish oil diet was demonstrated by the incorporation of fish oil-derived omega-3 fatty acids into plasma, leukocyte, and erythrocyte lipids. In control hamsters (n = 7) and fish oil-fed hamsters (n = 7), leukocyte/endothelium interaction was assessed in the time course after intravenous injection of human LDL (4 mg/kg), oxidized by 7.5 microM Cu2+ (6 hours, 37 degrees C). In control hamsters, injection of oxLDL elicited the rolling and sticking of leukocytes to the endothelium of arterioles and postcapillary venules with a maximum 15 minutes after injection (arterioles: from 3 +/- 1 to 91 +/- 25 cells/mm2 at 15 minutes; venules: from 13 +/- 6 to 150 +/- 46 cells/mm2 at 15 minutes; mean +/- SD). This phenomenon was significantly reduced in fish oil-fed hamsters, where 15 minutes after injection of oxLDL leukocyte sticking reached a maximum of only 15 +/- 7 and 20 +/- 5 cells/mm2 in arterioles and postcapillary venules, respectively (p less than 0.01 versus control animals). CONCLUSIONS: The results of the present study suggest that inhibition of leukocyte/endothelium interaction may be one of the mechanisms by which dietary fish oil exerts its protective effects on experimental and clinical atherogenesis.
Assuntos
Endotélio Vascular/fisiologia , Óleos de Peixe/farmacologia , Leucócitos/fisiologia , Lipoproteínas LDL/administração & dosagem , Animais , Arteriosclerose/prevenção & controle , Adesão Celular/fisiologia , Cricetinae , Ácidos Graxos Ômega-3/sangue , Leucócitos/química , Lipoproteínas LDL/metabolismo , Mesocricetus , Microscopia de Fluorescência , OxirreduçãoRESUMO
Epidemiologic observations and experimental studies have demonstrated a protective effect of dietary fish oil on the clinical manifestations of ischemia-reperfusion injury. To investigate the underlying mechanisms, we used the dorsal skinfold chamber model for intravital fluorescence microscopy of the microcirculation in striated muscle of awake hamsters. In control hamsters (n = 7), reperfusion after a 4-hr pressure-induced ischemia to the muscle tissue elicited the adhesion of fluorescently stained leukocytes to the endothelium of postcapillary venules, capillary obstruction, and the break-down of endothelial integrity. These microvascular manifestations of ischemia-reperfusion injury were significantly attenuated in animals (n = 7) when fed with a fish oil-enriched diet for 4 weeks prior to the experiments. In leukocyte total lipids, the fish oil diet resulted in a substantial displacement of arachidonic acid, the precursor of the potent adhesion-promoting leukotriene (LT) B4, by fish oil-derived eicosapentaenoic acid, the precursor of biologically less potent LTB5, emphasizing the mediator role of LTB4 in ischemia-reperfusion injury. These results suggest that the preservation of microvascular perfusion by dietary fish oil contributes to its protective effects on the clinical manifestations of ischemia-reperfusion injury.
Assuntos
Gorduras na Dieta/uso terapêutico , Óleos de Peixe/uso terapêutico , Isquemia/prevenção & controle , Leucotrieno B4/farmacologia , Microcirculação/efeitos dos fármacos , Músculos/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Animais , Viscosidade Sanguínea/efeitos dos fármacos , Cricetinae , Fibrinogênio/metabolismo , Hemodinâmica/efeitos dos fármacos , Mesocricetus , Microcirculação/fisiopatologia , Tempo de Tromboplastina ParcialRESUMO
In 12 patients with bronchial asthma the effects of acupuncture (45 tests altogether) on airway resistance have been investigated. In 9 patients there was a significant decrease of airway resistance 10 minutes, 1 hour and 2 hours after the end of acupuncture. The lowest level for airway resistance (70.1% of control value) was reached during the first hour after acupuncture. The possibility of a merely suggestive effect could be excluded, because "placebo-acupunctures" did not change airway resistance significantly. The comparison with a parasympatholytic acting drug as a metered aerosol (Atrovent) demonstrated that acupuncture had a somewhat weaker bronchospasmolytic effect. Three patients did not show any reaction after repeated acupunctures.
Assuntos
Terapia por Acupuntura , Asma/terapia , Adolescente , Adulto , Obstrução das Vias Respiratórias/diagnóstico , Asma/fisiopatologia , Humanos , Pessoa de Meia-Idade , Pletismografia TotalRESUMO
In 12 patients with bronchial asthma the effects of acupuncture (45 tests altogether) on airway resistance have been investigated. In 9 patients there was a significant decrease of airway resistance 10 minutes, 1 hour and 2 hours after the end of acupuncture. The lowest level for airway resistance (70,1% of control value) was reached during the first hour after acupuncture. The possibility of a merely suggestive effect could be excluded, because "placebo-acupunctures" did not change airway resistance significantly. The comparison with a parasympatholytic acting drug as a metered aerosol (Atrovent) demonstrated that acupuncture had a some-what weaker bronchospasmolytic effect. 3 patients showed after repeated acupunctures no reaction whatever.