RESUMEN
OBJECTIVES: We identified intermittent gait disturbance (IGD) observed in the mild stage of idiopathic normal pressure hydrocephalus (iNPH). The first purpose of this study was to clarify the temporal gait profile of IGD during long-distance gait. The second purpose was to confirm the difference in treatment effect after cerebrospinal fluid (CSF) shunting in patients with and without IGD. MATERIALS AND METHODS: Fourteen consecutive iNPH patients with mild gait disturbance with a timed up-and-go (TUG) of <20 seconds were prospectively enrolled in the study. All patients were asked "Do you experience gait difficulty after over five minutes of walking?" Seven "yes" patients formed the IGD group, and seven "no" patients formed the persistent gait disturbance (PGD) group. One day before and 7 days after CSF shunting, gait function was evaluated by the 6-minute walk test (6MWT) and TUG. RESULTS: Preoperatively, all patients in the IGD group demonstrated features of IGD during the 6MWT, characterized by a progressive pattern of decreased gait speed and step length with increased cadence and absence of leg pain. Post-operatively, these features of IGD improved in all patients. In the PGD group, preoperative walking did not significantly worsen during the 6MWT and did not significantly change 7 days after treatment. Improvement of gait symptoms 1 week after CSF shunting could be detected with 6MWT instead of TUG. CONCLUSIONS: Intermittent gait disturbance is not a rare symptom in mild stage of iNPH and may serve as an important clinical diagnostic marker for identifying mild iNPH patients.
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Trastornos Neurológicos de la Marcha/etiología , Hidrocéfalo Normotenso/complicaciones , Hidrocéfalo Normotenso/cirugía , Anciano , Anciano de 80 o más Años , Derivaciones del Líquido Cefalorraquídeo , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) is a promising real-time navigation method in the surgical resection of malignant gliomas. In order to determine whether this method is applicable to metastatic brain tumors, we evaluated the usefulness of intraoperative fluorescence patterns and histopathological features in patients with metastatic brain tumors. METHODS: We retrospectively reviewed the cases of 16 patients with metastatic brain tumors who underwent intraoperative 5-ALA fluorescence-guided resection. Patients were given 20 mg/kg of 5-ALA orally 2 h prior to the surgery. High-powered excitation illumination and a low-pass filter (420, 450, or 500 nm) were used to visualize the fluorescence of protoporphyrin IX (PpIX), the 5-ALA metabolite. We evaluated the relationships between the fluorescence and histopathological findings in both tumoral and peritumoral brain tissue. RESULTS: Tumoral PpIX fluorescence was seen in only 5 patients (31%); in the remaining 11 patients (69%), there was no fluorescence in the tumor bulk itself. In 14 patients (86%), vague fluorescence was seen in peritumoral brain tissue, at a thickness of 2-6 mm. The histopathological examination found cancer cell invasion of adjacent brain tissue in 75% of patients (12/16), at a mean ± SD depth of 1.4 ± 1.0 mm (range 0.2-3.4 mm) from the microscopic border of the tumor. There was a moderate correlation between vague fluorescence in adjacent brain tissue and the depth of cancer cell invasion (P = 0.004). CONCLUSION: Peritumoral fluorescence may be a good intraoperative indicator of tumor extent, preceding more complete microscopic gross total resection. TRIAL REGISTRATION: Institutional Review Board of Osaka Medical College No. 42, registered February 17, 1998, and No. 300, registered April 1, 2008. They were retrospectively registered.
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Ácido Aminolevulínico/administración & dosificación , Neoplasias Encefálicas/cirugía , Procedimientos Neuroquirúrgicos/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Protoporfirinas/química , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Ácido Aminolevulínico/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Femenino , Fluorescencia , Humanos , Cuidados Intraoperatorios/métodos , Imagen por Resonancia Magnética , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Procedimientos Neuroquirúrgicos/instrumentación , Estudios Retrospectivos , Cirugía Asistida por Computador/instrumentaciónRESUMEN
The objective of this study was to investigate the effect of intrauterine infusion with liquid paraffin (LP) on phagocytic migration into the uterus of cows. Smears of swab samples of the external os of the cervix and discharges collected inside the vagina were obtained in multiparous dairy cows (n = 10) that had been infused with 50 ml of LP (LP group: n = 5) or physiological saline (PS group: n = 5) on day 10 or 11 after ovulation (day 0: ovulation). The samples were collected for cytological examination 0 (just before), 0.25, 1, 2, 3, 4, 6, 8, 12 and 24 h after LP or PS infusion and then at daily intervals until subsequent ovulation. The number of neutrophils increased significantly (p < 0.05) for 8 days compared with the pre-infusion level in the LP group and for 2 days in the PS group. The average numbers of neutrophils in the LP group were significantly (p < 0.05) greater than those in the PS group on 3, 4, 5 and 8 days after infusion. The number of monocytes from 6 h to 8 days after LP infusion was significantly higher than that before infusion (p < 0.05). The average numbers of monocytes at 4 and 6 h and 1 day after infusion in the LP group were significantly higher than those in the PS group. These findings indicate that LP stimulates phagocytic migration into the uterine lumen in cows and that LP infusion into the uterus might enhance uterine defence mechanisms during uterine infection.
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Bovinos , Moco del Cuello Uterino/citología , Aceite Mineral/farmacología , Fagocitos/efectos de los fármacos , Útero/citología , Útero/efectos de los fármacos , Animales , Movimiento Celular , Vías de Administración de Medicamentos , Femenino , Aceite Mineral/administración & dosificación , Fagocitos/citologíaRESUMEN
The fine structure of mitochondria and mitochondrial nucleoids in exponentially growing Physarum polycephalum was studied at various periods throughout the mitochondrial division cycle by light and electron microscopy. The mitochondrial nucleoid elongates lingitudinally while the mitochondrion increases in size. When the nucleoid reaches a length of approximately 1.5 mum the mitochondrial membrane invaginates at the center of the mitochondrion and separates the mitochondrial contents. However, the nucleoid does not divide even when the mitochondrial sections are connected by a very narrow bridge. Just before division of the mitochondrion, the nucleoid divides by constriction of the limiting membrane of the dividing mitochondrion. After division, one end of the nucleoid appears to be associated with the inner mitochondrial membrane. The nucleoid then again becomes situated in the center of the mitochondrion before repeating these same processes.
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Mitocondrias/ultraestructura , Mixomicetos/ultraestructura , Physarum/ultraestructura , ADN Mitocondrial/biosíntesis , Membranas/ultraestructura , Mitocondrias/metabolismoRESUMEN
In flowering plants, guidance of the pollen tube to the embryo sac (the haploid female gametophyte) is critical for successful fertilization. The target embryo sac may attract the pollen tube as the final step of guidance in the pistil. We show by laser cell ablation that two synergid cells adjacent to the egg cell attract the pollen tube. A single synergid cell was sufficient to generate an attraction signal, and two cells enhanced it. After fertilization, the embryo sac no longer attracts the pollen tube, despite the persistence of one synergid cell. This cessation of attraction might be involved in blocking polyspermy.
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Magnoliopsida/fisiología , Estructuras de las Plantas/citología , Estructuras de las Plantas/fisiología , Polen/fisiología , Técnicas de Cultivo , Células Germinativas/citología , Células Germinativas/fisiología , Rayos Láser , Magnoliopsida/citología , Reproducción , Semillas/fisiología , Rayos UltravioletaRESUMEN
A chloroplast RNA polymerase sigma factor is encoded by a nuclear gene, sigA, in the red alga Cyanidium caldarium RK-1. The encoded protein functions as an RNA polymerase sigma factor in vitro and it is localized to the chloroplast in vivo. SigA shows high sequence similarity to the sigma factors of cyanobacteria, which is indicative of the ancestral endosymbiotic event and subsequent transfer of the sigA gene to the nuclear genome.
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Cloroplastos/enzimología , ARN Polimerasas Dirigidas por ADN/genética , Rhodophyta/genética , Factor sigma/genética , Secuencia de Aminoácidos , Secuencia de Bases , Southern Blotting , Núcleo Celular/genética , Cloroplastos/genética , ARN Polimerasas Dirigidas por ADN/química , ARN Polimerasas Dirigidas por ADN/aislamiento & purificación , ARN Polimerasas Dirigidas por ADN/metabolismo , Datos de Secuencia Molecular , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Rhodophyta/enzimología , Rhodophyta/ultraestructura , Alineación de Secuencia , Factor sigma/química , Factor sigma/aislamiento & purificación , Factor sigma/metabolismoRESUMEN
OBJECTIVES: To determine if the International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification of lupus nephritis (LN) is helpful in predicting renal outcome. METHODS: A total of 92 patients with LN who underwent renal biopsy in our hospital were re-classified according to the ISN/RPS 2003 criteria. RESULTS: The mean patient age was 36.8 yrs and the median observation period was 65 months. The relative frequency for each class was as follows: Class I (minimal mesangial LN) 0%, Class II (mesangial proliferative LN) 13%, Class III (focal LN) 17%, Class IV (diffuse LN) 60% and Class V (membranous LN) 10%. Within Class IV, diffuse segmental (Class IV-S) was 25% and diffuse global (Class IV-G) 75%. During the observation period, renal function was more likely to deteriorate in Class IV-G cases than in Class IV-S cases. Importantly, when Class IV-G was subdivided into cases involving active lesion alone [IV-G (A)] or chronic lesion [IV-G (A/C)], the majority of cases in IV-G (A) was nephrotic, but responded well to therapy. In contrast, renal function declined only in IV-G (A/C) cases. Patients with Class IV-G (A/C) had persistent proteinuria in spite of intensified therapies. Moreover, the higher proportion of chronic lesions was related with the deterioration of renal function. CONCLUSIONS: This study showed that in Class IV-G cases, renal outcome differed in the presence of chronicity. Chronicity could be a critical factor in predicting outcome. Thus, the revised classification of LN is clinically valuable in identifying different renal outcomes among patients with diffuse LN.
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Nefritis Lúpica/clasificación , Adulto , Biomarcadores/sangre , Enfermedad Crónica , Creatinina/sangre , Femenino , Humanos , Fallo Renal Crónico/patología , Glomérulos Renales/patología , Glomérulos Renales/fisiopatología , Nefritis Lúpica/patología , Nefritis Lúpica/fisiopatología , Masculino , Persona de Mediana Edad , Pronóstico , Proteinuria , Estadísticas no Paramétricas , Resultado del TratamientoRESUMEN
OBJECTIVE: IL-19 is a novel cytokine of the IL-10 family. In this study, we sought to examine whether IL-19 plays a role in the pathogenesis of RA. METHODS: Expression of IL-19, IL-20 receptor 1 (IL-20R1) and IL-20R2 was examined by RT-PCR and immunohistochemical analysis in rheumatoid synovium. The effects of IL-19 on synovial cells established from rheumatoid synovium (RASCs), with regard to IL-6 production and signal transducers and activators of transcription3 (STAT3) activation, were examined by ELISA and western blot analysis, respectively. The effect of IL-19 on RASC apoptosis was examined by Hoechst staining, flow cytometry analysis of annexin V binding and caspase-3 activity. RESULTS: IL-19, IL-20R1 and IL-20R2 mRNA were detected by RT-PCR in synovial tissues from RA patients. Immunohistochemical analysis showed IL-19 was predominantly expressed in the hyperplastic lining layers of RA synovial tissues. The majority of IL-19-positive cells were vimentin-positive and CD68-positive synovial cells, serving as markers of fibroblasts and macrophages, respectively. IL-20R1 and IL-20R2 (IL-20Rs) were expressed in both the lining and sublining layers of RA synovium. In RASC, IL-19 was induced by lipopolysaccharide stimulation and constitutive expression of IL-20Rs was observed, suggesting IL-19 has an autocrine action. In terms of this function, IL-19 induced STAT3 activation and increased IL-6 production by RASC above the medium control. Moreover, IL-19 significantly reduced RASC apoptosis induced by serum starvation. CONCLUSIONS: These data suggest that IL-19, produced by synovial cells, promotes joint inflammation in RA by inducing IL-6 production and decreasing synovial cell apoptosis.
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Artritis Reumatoide/inmunología , Interleucinas/metabolismo , Receptores de Interleucina/metabolismo , Membrana Sinovial/inmunología , Apoptosis/inmunología , Artritis Reumatoide/patología , Caspasa 3/metabolismo , Células Cultivadas , Humanos , Hiperplasia/inmunología , Interleucina-6/biosíntesis , Interleucinas/inmunología , Proteínas Recombinantes/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/inmunología , Membrana Sinovial/patologíaRESUMEN
We examined the time course of neurological deficits in gerbils after an intracerebral hemorrhage (ICH) induced by autologous blood infusion and examined its correlation with the severity of perihematomal edema. Mongolian gerbils (n = 15) were subjected to stereotaxic autologous blood infusion (30 or 60 microL) into the left caudate nucleus. Corner-turn and forelimb-placing tests were performed before, and 1 and 3 days after ICH. Perihematomal water content was measured by tissue gravimetry. Gerbils developed neurological deficits and perihematomal edema at day 1 after ICH. Both neurological deficits and perihematomal edema were significantly greater in animals with 60 microL blood infusion compared to the 30 microL infusion group, and both neurological deficits and edema were also greater at 3 days compared to 1 day after ICH. The severity of neurological deficits paralleled the degree of perihematomal edema. We conclude that the Mongolian gerbil is a suitable model for studies on the behavioral effects of ICH.
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Edema Encefálico/etiología , Hemorragia Cerebral/complicaciones , Enfermedades del Sistema Nervioso/etiología , Animales , Encéfalo/metabolismo , Edema Encefálico/patología , Hemorragia Cerebral/etiología , Modelos Animales de Enfermedad , Miembro Anterior/fisiopatología , Lateralidad Funcional , Gerbillinae , Masculino , Enfermedades del Sistema Nervioso/patología , Reacción a la Transfusión , Agua/metabolismoRESUMEN
Acute graft-versus-host disease (GVHD) is a major complication of bone marrow transplantation (BMT) and is characterized by hematopoietic dysfunction, immunosuppression, and tissue injury in the skin, liver, and intestinal mucosa. Hepatocyte growth factor (HGF), originally identified and cloned as a potent mitogen for hepatocytes, induces mitogenic and antiapoptotic activity in various epithelial cells and promotes hematopoiesis. Working in a murine model of acute GVHD, we performed repeated transfection of the human HGF cDNA into skeletal muscle and showed that this treatment inhibited apoptosis of intestinal epithelial cells and donor T-cell infiltration into the liver, thereby ameliorating the enteropathy and liver injury caused by acute GVHD. HGF also markedly suppressed IFN-gamma and TNF-alpha expression in the intestine and liver and decreased the serum IL-12. Furthermore, extramedullary hematopoiesis by donor cells was increased, and the survival rate was improved. These results suggest that HGF may be useful for controlling acute GVHD after allogeneic BMT.
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Trasplante de Médula Ósea/efectos adversos , Enfermedad Injerto contra Huésped/terapia , Hematopoyesis Extramedular/fisiología , Factor de Crecimiento de Hepatocito/uso terapéutico , Transfección , Animales , Modelos Animales de Enfermedad , Enfermedad Injerto contra Huésped/patología , Enfermedad Injerto contra Huésped/fisiopatología , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Interferón gamma/genética , Interferón gamma/metabolismo , Interleucina-12/sangre , Intestinos/patología , Liposomas , Hígado/patología , Hígado/fisiología , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/fisiología , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapéutico , Bazo/citología , Bazo/fisiología , Timo/citología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The precise guidance of the pollen tube to the embryo sac is critical to the successful sexual reproduction of flowering plants. We demonstrate here the guidance of the pollen tube to the embryo sac in vitro by using the naked embryo sac of Torenia fournieri, which protrudes from the micropyle of the ovule. We developed a medium for culture of both the ovule and the pollen tube of T. fournieri and cocultivated them in a thin layer of solid medium. Although pollen tubes that had germinated in vitro passed naked embryo sacs, some pollen tubes that grew semi-in vitro through a cut style arrived precisely at the site of entry into the embryo sac, namely, the filiform apparatus of the synergids. When pollen tubes were unable to enter the embryo sac, they continuously grew toward the same filiform apparatus, forming narrow coils. Pollen tubes selectively arrived at complete, unfertilized embryo sacs but did not arrive at those of heat-treated ovules or those with disrupted synergids. These results convincingly demonstrate that pollen tubes are specifically attracted to the region of the filiform apparatus of living synergids in vitro.
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BACKGROUND AND PURPOSE: Human herpesvirus-6 (HHV-6)-associated encephalopathy tends to develop in immunocompromised patients. Neurologic symptoms, such as disorientation, short-term memory loss, convulsion, coma, and hypopnea could occur, but they may be nonspecific. We retrospectively reviewed MR images of 6 adults with HHV-6-associated encephalopathy to study characteristic imaging findings that could be useful in making the diagnosis. MATERIALS AND METHODS: Between 2003 and 2005, we encountered 6 cases of HHV-6-associated encephalopathy (3 men and 3 women; age range, 36-55 years) in 3 hospitals. The diagnosis was made clinically according to the neurologic symptoms accompanied by high-level copies of HHV-6 DNA in CSF or peripheral blood by quantitative polymerase chain reaction without the detection of any other infectious pathogen. RESULTS: All 6 patients had abnormal hippocampus/amygdala findings on presentation, and no other regions were involved. In the early period (0-2 days from onset), abnormal high signal intensity on fluid-attenuated inversion recovery (FLAIR) imaging (2 of 3, 67%) and on diffusion-weighted images accompanied by apparent diffusion coefficient (ADC) reduction (2 of 2, 100%) were observed. In the middle period (3-30 days), abnormal low signal intensity on T1-weighted images (5 of 6, 83%) and abnormal high signal intensity on T2-weighted images (4 of 6, 67%) and FLAIR (5 of 6, 83%) were confirmed. In the late period (> 30 days), we saw the resolution of signal intensity abnormalities and the appearance of atrophic change (4 of 4, 100%) of the affected regions. CONCLUSION: HHV-6-associated encephalopathy in adults tends to affect the mesial temporal lobe. MR imaging is useful for detecting HHV-6 encephalopathy and distinguishing it from the other diseases of the central nervous system in immunocompromised patients.
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Encefalitis Viral/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Herpesvirus Humano 6 , Imagen por Resonancia Magnética , Infecciones por Roseolovirus/diagnóstico , Adulto , Encefalitis Viral/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones por Roseolovirus/etiologíaRESUMEN
BACKGROUND: Generic omeprazole contains the same active ingredient as original omeprazole and require verification of the bioequivalence with original omeprazole. However, very few clinical studies have been reported. AIMS: A prospective, randomised, open-label, crossover study to compare acid-suppressive effect of generic omeprazole with that of original omeprazole. SUBJECTS: Seven healthy Helicobacter pylori-negative subjects of CYP2C19 extensive metaboliser. METHODS: Intragastric pH was measured for 24 h without medications (placebo) and on day 7 of repeated administration of 10 mg once daily after breakfast of original omeprazole, Omeprazon, or three brands of generic omeprazole, Omeprazole-Towa, Ovulanze or Omerap. RESULTS: Median values of intragastric pH and percentages of time with pH>4 for 24 h were significantly higher with administration of any omeprazole formulation compared with placebo (P<0.05, Wilcoxon signed-rank test). Whereas, during the night-time period (20:00-08:00 h), percentages of time with pH>4 with Omeprazole-Towa and Omerap were not significantly higher than placebo. Compared with Omeprazon, these two parameters for 24 h showed significantly greater inter-subject variations with Omeprazole-Towa (P<0.05 and P<0.01, F-test) and Ovulanze (P<0.05). CONCLUSIONS: Acid-suppressive effects of some brands of generic omeprazole are not the same as original omeprazole. These differences might be reflected in clinical outcomes.
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Antiulcerosos/administración & dosificación , Medicamentos Genéricos , Omeprazol/administración & dosificación , Adulto , Antiulcerosos/farmacocinética , Hidrocarburo de Aril Hidroxilasas/efectos de los fármacos , Química Farmacéutica , Estudios Cruzados , Citocromo P-450 CYP2C19 , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacocinética , Femenino , Ácido Gástrico/metabolismo , Determinación de la Acidez Gástrica , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Genotipo , Helicobacter pylori , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Japón , Masculino , Oxigenasas de Función Mixta/efectos de los fármacos , Omeprazol/farmacocinética , Estudios Prospectivos , Valores de Referencia , Equivalencia TerapéuticaRESUMEN
We investigated, at both light and ultrastructural levels, the fate of swollen astrocytes and remodeling of neurites connected to disseminated, dying neurons in the ischemic neocortical penumbra. Specimens from left cerebral cortex were cut coronally at the infundibulum and observed by light and electron microscopy. We measured synapses and spines, and the thickness of neuritic trunks in the neuropil on electron microscopy photos. We also determined percent volume of axon terminals and spines by Weibel's point-counting method. Astrocytic swelling gradually subsided from day 4 after the ischemic insult, with increases in cytoplasmic glial fibrils and GFAP-positive astrocytes. Disseminated dying electron-dense neurons were fragmented by invading astrocytic cell processes and accumulated as granular pieces. The number of synapses and spines and total percent volume of axon terminals and spines decreased with an increasing sparsity of synaptic vesicles until day 4. One to 12 weeks after the ischemic insult, these values increased to or exceeded control values, and sprouting and increased synaptic vesicles were seen. Axons that had been attached to the dying neurons appeared to have shifted their connections to the spines and the neurites of the surviving neurons, increasing their thickness. Astrocytic restitution and neuronal remodeling processes started at 4 days continuing until 12 weeks after ischemic insult.
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Astrocitos/ultraestructura , Axones/ultraestructura , Edema Encefálico/patología , Isquemia Encefálica/patología , Corteza Cerebral/ultraestructura , Neuritas/ultraestructura , Daño por Reperfusión/patología , Animales , Apoptosis , Edema Encefálico/etiología , Isquemia Encefálica/complicaciones , Células Cultivadas , Corteza Cerebral/irrigación sanguínea , Gerbillinae , Regeneración Nerviosa , Neuronas/ultraestructura , Daño por Reperfusión/complicacionesRESUMEN
Knowledge of the biomechanical properties of postischemic brain tissue is important for understanding the mechanisms of postischemic secondary brain tissue injury. We describe the method and results of biomechanical property measurement in ex vivo postischemic brain tissue by applying an indentation method. Mongolian gerbils were subjected to a transient unilateral hemispheric ischemia. At day 1 after ischemia, multi-parametric MRI was performed, the brain was removed under anesthesia, sliced, and kept in a container with silicone oil for the measurement. A compression probe attached to a pressure transducer was inserted to a pre-determined depth at the regions of interest and maintained at a constant speed. A pressure relaxation curve was recorded for the calculation of elasticity modulus (E) and viscosity modulus (eta) according to Maxwell-Voigt's 3-element model. One day after ischemia, E and eta decreased to 78.7% and 73.1% of the control level, respectively. This decrease corresponded to a mild decrease in apparent diffusion coefficient (ADC) and magnetization transfer ratio, and an increase in T2 value. Tissue water content increased to 105.1% of control. Microvacuolation with demyelination and axonal disruption was evident in the postischemic brain tissue.
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Fenómenos Biomecánicos/métodos , Edema Encefálico/fisiopatología , Isquemia Encefálica/fisiopatología , Encéfalo/fisiopatología , Pruebas de Dureza/métodos , Modelos Neurológicos , Estimulación Física/métodos , Animales , Fenómenos Biomecánicos/instrumentación , Edema Encefálico/etiología , Isquemia Encefálica/complicaciones , Simulación por Computador , Elasticidad , Femenino , Gerbillinae , Pruebas de Dureza/instrumentación , Masculino , Estimulación Física/instrumentación , Estrés Mecánico , ViscosidadRESUMEN
Eosinophilic neurons (ENs) appear in the post-ischemic cortex; however, whether there are differences in the time profile for different cortical layers and the fate of the cortex with ENs is largely unknown. We examined the time profile of ENs in different cortical layers and evolution of cortical atrophy after transient cerebral ischemia in Mongolian gerbils. Unilateral forebrain ischemia was induced twice by 10-minute unilateral common carotid artery occlusions. Brains at 24 hours, 4 days, and 2, 4, and 16 weeks post-ischemia were prepared for morphometric analysis. Quantitative analysis of ENs in regions of interest in the rostral and caudal cortex showed the highest number of ENs at 4 days post-ischemia in layers 3 and 6. Reduction in ENs after this peak was slower in layer 6 than in layer 3 in both rostral and caudal cortex, and this difference was significant in layer 6 of the caudal cortex. Infarcts with significant atrophy appeared in the rostral cortex. In the caudal cortex, only selective neuronal death with mild but distinct atrophy was observed. We observed a significant difference between cortical layers in the time profile of ENs in the post-ischemic cortex. Selective neuronal death without infarction was sufficient to induce cortical atrophy after transient cerebral ischemia.
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Isquemia Encefálica/patología , Corteza Cerebral/patología , Eosinófilos/patología , Red Nerviosa/patología , Neuronas/patología , Animales , Atrofia , Gerbillinae , Masculino , Factores de TiempoRESUMEN
The purpose of this study was to investigate cognitive/memory dysfunctions and the pathological process contributing to such dysfunction following moderate lateral fluid percussion injury (LFPI) in Mongolian gerbils. Mongolian gerbils were subjected to moderate LFPI (1.3 1.6 atm). During 7 days post-trauma, spatial cognitive and memory dysfunctions were evaluated by T-maze test (TMT). At 6 hours, 24 hours, and 7 days post-injury, animals were sacrificed and the brains were prepared for Kluver-Barrera staining and immunostaining of beta-amyloid precursor protein (APP). In LFPI animals, the spontaneous alternation rate in the TMT remained below the random alternation rate (< 50%) on all post-injury test days. These animals also showed a transient tendency to choose only the right arm (ipsilateral to the injury) in the TMT at 6 hours and 24 hours after injury. Significant accumulation of APP was found widespread in the ipsilateral hemisphere including directly injured cortex, subcortical white matter, and hippocampal formation at 6 hours and 24 hours post-injury, while on day 7, the increased immunoreactivity of APP subsided. These results suggest that the widespread axonal degeneration of the white matter might contribute to the unilateral spatial neglect and memory deficit in the acute stage after LFPI.
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Precursor de Proteína beta-Amiloide/metabolismo , Lesiones Encefálicas/fisiopatología , Trastornos del Conocimiento/fisiopatología , Modelos Animales de Enfermedad , Traumatismos Cerrados de la Cabeza/fisiopatología , Trastornos de la Memoria/fisiopatología , Animales , Lesiones Encefálicas/complicaciones , Trastornos del Conocimiento/etiología , Gerbillinae , Traumatismos Cerrados de la Cabeza/complicaciones , Trastornos de la Memoria/etiologíaRESUMEN
We investigated the correlation between the changes in diffusion tensor magnetic resonance imaging, regional water content, and tissue ultrastructure after vasogenic brain edema induced by cortical cold lesioning. In this cat model, E3 in the white matter was dominantly increased while fractional anisotropy (FA) was significantly decreased 8 hours after cortical cold lesioning. This finding indicates that water diffusion in the cortical white matter mainly increased perpendicularly rather than parallel to the direction of the nerve fibers. Additionally, in the area where edema is mild or moderate (tissues with water content of 65% to 75%), FA in the chronic phase was significantly lower than that in the acute phase. Histological examination demonstrated disordered arrangement of nerve fibers, highly dissociated neuronal fibers due to extracellular accumulation of protein rich-fluid, and enlarged interfiber spaces in the acute phase.
Asunto(s)
Agua Corporal/metabolismo , Edema Encefálico/diagnóstico , Edema Encefálico/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Imagen de Difusión por Resonancia Magnética/métodos , Modelos Animales de Enfermedad , Animales , Edema Encefálico/patología , GatosRESUMEN
We examined temporal profiles of neurological dysfunctions and compared them with apparent diffusion coefficient (ADC) and T2 changes in ischemic cortical regions after transient focal cerebral ischemia in Mongolian gerbils. Mongolian gerbils (n = 7) underwent right common carotid artery occlusion for 20 minutes. Asymmetric motor behavior and unilateral somatosensory dysfunction were quantified by the elevated body swing test and the bilateral asymmetry test at 0, 2, 3, and 8 days after ischemia. The results were compared to the ADC and T2 changes in the primary motor cortex and the somatosensory cortex. Transient motor dysfunction was observed at day 2 after ischemia. MRI revealed transient and mild ADC decrease without T2 increase at day 2 after ischemia in the primary motor cortex. Persistent somatosensory dysfunction was observed at 2, 3, and 8 days after ischemia, which corresponded to a moderate ADC decrease, and a mild T2 increase in the primary somatosensory cortex at days 2 and 3 after ischemia. Time profiles of neurological deficits concurred with ADC changes of the post-ischemic cortex responsible for the deficits. The post-ischemic lesions responsible for the neurological deficits were detectable by using ADC mapping in the acute phase after transient focal cerebral ischemia.
Asunto(s)
Mapeo Encefálico/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Modelos Animales de Enfermedad , Interpretación de Imagen Asistida por Computador/métodos , Ataque Isquémico Transitorio/diagnóstico , Enfermedades del Sistema Nervioso/diagnóstico , Animales , Gerbillinae , Ataque Isquémico Transitorio/complicaciones , Masculino , Enfermedades del Sistema Nervioso/etiología , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The objective of this study was to establish a rodent model of vascular dementia that showed long-term cognitive and neuropsychological deficits, and to correlate those behavioral deficits with the patterns of ischemic lesions, thus providing a platform for future testing of potential therapeutic agents. In Mongolian gerbils, either 5-minute single bilateral common carotid artery occlusion (SBCCAO) or repetitive bilateral common carotid artery occlusion (two 7-minute occlusions, RBCCAO) was induced, and the behavioral deficits were evaluated using 2 tests: a modified open-field test with an escape zone to evaluate changes in anxiety and locomotor activity, and a T-maze test to assess cognitive dysfunction. SBCCAO did not induce anxiety changes but caused transient locomotor hyperactivity and mild cognitive deficits. Only pyramidal neuronal death was found in the bilateral CA1 sector of the hippocampus following SBCCAO. In contrast, RBCCAO induced persistent locomotor hyperactivity, reduced anxiety, and caused severe cognitive deficits at 4 weeks post-ischemia. RBCCAO caused significant atrophy associated with diffuse selective neuronal death in the bilateral cerebral cortex and caudate nucleus, as well as the CA1 region. The repetitive ischemia model appears to be a potentially useful platform for the long-term analysis of cognitive and neuropsychological symptoms associated with vascular dementia.