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1.
J Transl Med ; 20(1): 517, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36348371

RESUMEN

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant muscular disorder characterized by asymmetric muscle wasting and weakness. FSHD can be subdivided into two types: FSHD1, caused by contraction of the D4Z4 repeat on chromosome 4q35, and FSHD2, caused by mild contraction of the D4Z4 repeat plus aberrant hypomethylation mediated by genetic variants in SMCHD1, DNMT3B, or LRIF1. Genetic diagnosis of FSHD is challenging because of the complex procedures required. METHODS: We applied Nanopore CRISPR/Cas9-targeted resequencing for the diagnosis of FSHD by simultaneous detection of D4Z4 repeat length and methylation status at nucleotide level in genetically-confirmed and suspected patients. RESULTS: We found significant hypomethylation of contracted 4q-D4Z4 repeats in FSHD1, and both 4q- and 10q-D4Z4 repeats in FSHD2. We also found that the hypomethylation in the contracted D4Z4 in FSHD1 is moderately correlated with patient phenotypes. CONCLUSIONS: Our method contributes to the development for the diagnosis of FSHD using Nanopore long-read sequencing. This finding might give insight into the mechanisms by which repeat contraction causes disease pathogenesis.


Asunto(s)
Distrofia Muscular Facioescapulohumeral , Humanos , Distrofia Muscular Facioescapulohumeral/genética , Distrofia Muscular Facioescapulohumeral/diagnóstico , Proteínas de Homeodominio/genética , Metilación de ADN/genética , Cromosomas/metabolismo , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo
2.
Neuroimage ; 180(Pt A): 312-323, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-29331450

RESUMEN

In vivo calcium (Ca2+) imaging using two-photon microscopy allows activity to be monitored simultaneously from hundreds of individual neurons within a local population. While this allows us to gain important insights into how cortical neurons represent sensory information, factors such as photo-bleaching of the Ca2+ indicator limit imaging duration (and thus the numbers of stimuli that can be tested), which in turn hampers the full characterization of neuronal response properties. Here, we demonstrate that using an encoding model combined with presentation of natural movies results in detailed characterization of receptive field (RF) properties despite the relatively short time for data collection. During presentation of natural movie clips to macaque monkeys, we recorded fluorescence signals from primary visual cortex (V1) neurons that had been loaded with a Ca2+ indicator. For each recorded neuron, we constructed an encoding model that comprised an array of motion-energy filters that tiled over the RFs. We optimized the weight of each filter's output so that the linear sum of the outputs across the filters mimicked the neuron's Ca2+-signal responses. These models were able to predict the neural responses to a different set of natural movies with a significant degree of accuracy. Moreover, the orientation tunings of neurons simulated by the model were highly correlated with those experimentally obtained when grating stimuli were presented to the monkeys. The model predictions were also consistent with what is known about spatial frequency tunings, the structure of excitatory subfields of RFs (i.e., classical RFs), and functional maps for these RF properties in V1. Further analysis revealed a new aspect of V1 functional architecture; the extent and distribution of suppressive RF subfields varied among nearby neurons, while those for excitatory subfields were shared. Thus, applying our encoding-model analysis to two-photon Ca2+ imaging of neuronal responses to natural movies provides a reliable and efficient means of analyzing a wide range of RF properties in multiple neurons imaged in a local region.


Asunto(s)
Mapeo Encefálico/métodos , Modelos Neurológicos , Neuronas/metabolismo , Corteza Visual/fisiología , Animales , Calcio/metabolismo , Femenino , Macaca fascicularis , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Películas Cinematográficas , Compuestos Orgánicos , Estimulación Luminosa , Percepción Visual/fisiología
3.
J Neurosci ; 33(42): 16818-27, 2013 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-24133282

RESUMEN

A majority of neurons in the monkey primary visual cortex (V1) are tuned to stimulus orientations. Preferred orientations and tuning strengths vary among V1 neurons. The preferred orientation of neurons gradually changes across the cortex with occasional failures of this organization. How V1 neurons are arranged by the strength of orientation tuning and whether neuronal arrangement for tuning strength relates to orientation preference maps remains controversial. In this study, we performed in vivo two-photon calcium imaging in macaque V1 to examine the local spatial organization of orientation tuning at the level of single cells. We recorded fluorescence signals from individual neurons loaded with a calcium-sensitive dye in layer 2 and the uppermost tier of layer 3. The strength of orientation tuning was shared by nearby neurons, and changed across the cortex. The neurons with similar tuning strength were distributed across at least the entire thickness of layer 2. The tuning strength was weaker in regions where neurons exhibited heterogeneous preferred orientations, as compared with regions where neurons shared similar orientation preferences. Nearby direction-selective neurons often shared their preferred directions, although only a few neurons were direction selective in the layers examined. Thus, the orientation tuning strength of V1 neurons is partially predictable from the local structure of orientation map. The weaker orientation tuning we found in regions with heterogeneous orientation preferences suggests that orientation-independent interactions among local populations of V1 neurons play a critical role in determining their orientation tuning.


Asunto(s)
Neuronas/fisiología , Orientación/fisiología , Corteza Visual/fisiología , Vías Visuales/fisiología , Animales , Atención/fisiología , Mapeo Encefálico , Calcio/metabolismo , Femenino , Macaca fascicularis , Masculino , Estimulación Luminosa
4.
Rinsho Shinkeigaku ; 64(4): 286-291, 2024 Apr 24.
Artículo en Japonés | MEDLINE | ID: mdl-38508732

RESUMEN

A 52-year-old man had developed hearing loss since childhood, as well as recurrent foot ulcers and osteomyelitis since his forties. He presented with gait disturbance and dysarthria that had worsened over four years and a month, respectively. Neurological exams revealed cognitive impairment, proximal weakness of the lower extremities, generalized hyperrflexia, ataxia, sensory disturbances predominant in deep sensation, urinary retention, and gait instability. On nerve conduction study, no sensory nerve action potentials were evoked in the upper and lower limbs. Since his grandmother suffered from similar symptoms, we investigated genetic analysis, which revealed a missense mutation (c.1483T>C, p.Y495H) in DNA methyltransferase 1 gene. He was subsequently diagnosed with hereditary sensory and autonomic neuropathy 1E (HSAN1E). It is important to recognize that increased deep tendon reflex can be observed in HSAN1E.


Asunto(s)
Neuropatías Hereditarias Sensoriales y Autónomas , Mutación Missense , Humanos , Masculino , Persona de Mediana Edad , Neuropatías Hereditarias Sensoriales y Autónomas/genética , Neuropatías Hereditarias Sensoriales y Autónomas/diagnóstico
5.
Commun Biol ; 6(1): 924, 2023 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-37689776

RESUMEN

Cerebellar climbing fibers convey sensorimotor information and their errors, which are used for motor control and learning. Furthermore, they represent reward-related information. Despite such functional diversity of climbing fiber signals, it is still unclear whether each climbing fiber conveys the information of single or multiple modalities and how the climbing fibers conveying different information are distributed over the cerebellar cortex. Here we perform two-photon calcium imaging from cerebellar Purkinje cells in mice engaged in a voluntary forelimb lever-pull task and demonstrate that climbing fiber responses in 68% of Purkinje cells can be explained by the combination of multiple behavioral variables such as lever movement, licking, and reward delivery. Neighboring Purkinje cells exhibit similar climbing fiber response properties, form functional clusters, and share noise fluctuations of responses. Taken together, individual climbing fibers convey behavioral information on multiplex variables and are spatially organized into the functional modules of the cerebellar cortex.


Asunto(s)
Cerebelo , Células de Purkinje , Animales , Ratones , Axones , Calcio , Recompensa
6.
Front Neural Circuits ; 16: 842748, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35633733

RESUMEN

Reaching, grasping, and retrieving movements are essential to our daily lives and are common in many mammalian species. To understand the mechanism for controlling this movement at the neural circuit level, it is necessary to observe the activity of individual neurons involved in the movement. For stable electrophysiological or optical recordings of neural activity in a behaving animal, head fixation effectively minimizes motion artifacts. Here, we developed a new device that allows mice to perform reaching, grasping, and retrieving movements during head fixation. In this method, agar cubes were presented as target objects in front of water-restricted mice, and the mice were able to reach, grasp, and retrieve them with their forelimb. The agar cubes were supplied by a custom-made automatic dispenser, which uses a microcontroller to control the two motors to push out the agar cubes. This agar presentation system supplied approximately 20 agar cubes in consecutive trials. We confirmed that each agar cube could be presented to the mouse with an average weight of 55 ± 3 mg and positional accuracy of less than 1 mm. Using this system, we showed that head-fixed mice could perform reaching, grasping, and retrieving tasks after 1 week of training. When the agar cube was placed near the mice, they could grasp it with a high success rate without extensive training. On the other hand, when the agar cube was presented far from the mice, the success rate was initially low and increased with subsequent test sessions. Furthermore, we showed that activity in the primary motor cortex is required for reaching movements in this task. Therefore, our system can be used to study neural circuit mechanisms for the control and learning of reaching, grasping, and retrieving movements under head-fixed conditions.


Asunto(s)
Fuerza de la Mano , Desempeño Psicomotor , Agar , Animales , Fuerza de la Mano/fisiología , Macaca mulatta , Mamíferos , Ratones , Movimiento/fisiología , Desempeño Psicomotor/fisiología
7.
Brain Struct Funct ; 227(4): 1385-1403, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35286478

RESUMEN

Natural scenes are characterized by diverse image statistics, including various parameters of the luminance histogram, outputs of Gabor-like filters, and pairwise correlations between the filter outputs of different positions, orientations, and scales (Portilla-Simoncelli statistics). Some of these statistics capture the response properties of visual neurons. However, it remains unclear to what extent such statistics can explain neural responses to natural scenes and how neurons that are tuned to these statistics are distributed across the cortex. Using two-photon calcium imaging and an encoding-model approach, we addressed these issues in macaque visual areas V1 and V4. For each imaged neuron, we constructed an encoding model to mimic its responses to naturalistic videos. By extracting Portilla-Simoncelli statistics through outputs of both filters and filter correlations, and by computing an optimally weighted sum of these outputs, the model successfully reproduced responses in a subpopulation of neurons. We evaluated the selectivities of these neurons by quantifying the contributions of each statistic to visual responses. Neurons whose responses were mainly determined by Gabor-like filter outputs (low-level statistics) were abundant at most imaging sites in V1. In V4, the relative contribution of higher order statistics, such as cross-scale correlation, was increased. Preferred image statistics varied markedly across V4 sites, and the response similarity of two neurons at individual imaging sites gradually declined with increasing cortical distance. The results indicate that natural scene analysis progresses from V1 to V4, and neurons sharing preferred image statistics are locally clustered in V4.


Asunto(s)
Corteza Visual , Animales , Macaca mulatta , Neuronas/fisiología , Orientación/fisiología , Estimulación Luminosa/métodos , Corteza Visual/fisiología , Vías Visuales/fisiología
8.
Curr Biol ; 31(4): 733-741.e7, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33275889

RESUMEN

Orientation preference maps (OPMs) are a prominent feature of primary visual cortex (V1) organization in many primates and carnivores. In rodents, neurons are not organized in OPMs but are instead interspersed in a "salt and pepper" fashion, although clusters of orientation-selective neurons have been reported. Does this fundamental difference reflect the existence of a lower size limit for orientation columns (OCs) below which they cannot be scaled down with decreasing V1 size? To address this question, we examined V1 of one of the smallest living primates, the 60-g prosimian mouse lemur (Microcebus murinus). Using chronic intrinsic signal imaging, we found that mouse lemur V1 contains robust OCs, which are arranged in a pinwheel-like fashion. OC size in mouse lemurs was found to be only marginally smaller compared to the macaque, suggesting that these circuit elements are nearly incompressible. The spatial arrangement of pinwheels is well described by a common mathematical design of primate V1 circuit organization. In order to accommodate OPMs, we found that the mouse lemur V1 covers one-fifth of the cortical surface, which is one of the largest V1-to-cortex ratios found in primates. These results indicate that the primate-type visual cortical circuit organization is constrained by a size limitation and raises the possibility that its emergence might have evolved by disruptive innovation rather than gradual change.


Asunto(s)
Cheirogaleidae , Corteza Visual Primaria/anatomía & histología , Corteza Visual Primaria/fisiología , Animales , Cheirogaleidae/anatomía & histología , Cheirogaleidae/fisiología , Femenino , Masculino , Modelos Neurológicos , Neuronas/fisiología , Orientación , Corteza Visual Primaria/citología
9.
J Physiol ; 588(Pt 15): 2769-87, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20530116

RESUMEN

Thalamocortical afferents innervate both excitatory and inhibitory cells, the latter in turn producing disynaptic feedforward inhibition, thus creating fast excitation-inhibition sequences in the cortical cells. Since this inhibition is disynaptic, the time lag of the excitation-inhibition sequence could be approximately 2-3 ms, while it is often as short as only slightly above 1 ms; the mechanism and function of such fast IPSPs are not fully understood. Here we show that thalamic activation of inhibitory neurons precedes that of excitatory neurons, due to increased conduction velocity of thalamic axons innervating inhibitory cells. Developmentally, such latency differences were seen only after the end of the second postnatal week, prior to the completion of myelination of the thalamocortical afferent. Furthermore, destroying myelination failed to extinguish the latency difference. Instead, axons innervating inhibitory cells had consistently lower threshold, indicating they had larger diameter, which is likely to underlie the differential conduction velocity. Since faster activation of GABAergic neurons from the thalamus can not only curtail monosynaptic EPSPs but also make disynaptic ISPSs precede disynaptic EPSPs, such suppression theoretically enables a temporal separation of thalamically driven mono- and disynaptic EPSPs, resulting in spike sequences of 'L4 leading L2/3'. By recording L4 and L2/3 cells simultaneously, we found that suppression of IPSPs could lead to deterioration of spike sequences. Thus, from the end of the second postnatal week, by activating GABAergic neurons prior to excitatory neurons from the thalamus, fast feedforward disynaptic suppression on postsynaptic cells may play a role in establishing the spike sequences of 'L4 leading L2/3 cells'.


Asunto(s)
Potenciales de Acción/fisiología , Corteza Cerebral/fisiología , Inhibición Neural/fisiología , Tálamo/fisiología , Animales , Retroalimentación Fisiológica/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Vías Nerviosas/fisiología
10.
Acta Neuropathol ; 117(5): 575-82, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19198858

RESUMEN

Chloroquine, an anti-malaria drug, is known to cause myopathy with rimmed vacuole formation. Although it disrupts the lysosomal degradation of proteins, the precise mechanism underlying muscle fiber degeneration has remained unclear. We investigated the temporal profiles of muscle fiber degeneration in chloroquine-treated rats, paying special attention to endoplasmic reticulum (ER) stress and autophagy. Male Wistar rats were intraperitoneally injected with chloroquine diphosphate at a dosage of 50 mg/kg body weight every day. We examined the localization and levels of proteins related to ER stress and autophagy in soleus muscle by means of immunohistochemistry and Western blotting at 3, 5, and 7 weeks after the beginning of the treatment. At 3 weeks, the levels of LC3-II and amyloid-beta (Abeta) were increased. At 5 weeks, an unfolded protein response took place. At 7 weeks, rimmed vacuole formation became obvious. Interestingly, SERCA2, a Ca2+ -pump ATPase located in the endoplasmic/sarcoplasmic reticulum membrane was up-regulated at 5 weeks after treatment, but declined to the control level by 7 weeks. Taken together, these findings suggest that Abeta accumulation (at 3 weeks) caused by the disruption of lysosomal enzymes precedes an unfolded protein response (at 5 weeks). Next, activation of autophagy occurs (at 7 weeks), probably using sarcoplasmic reticulum membrane, the amount of which was increased. Chloroquine-treated rats could be useful for investigating the pathogenesis of diseases related to Abeta accumulation.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Antimaláricos/toxicidad , Autofagia , Cloroquina/análogos & derivados , Retículo Endoplásmico/patología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Animales , Antimaláricos/administración & dosificación , Autofagia/efectos de los fármacos , Western Blotting , Cloroquina/administración & dosificación , Cloroquina/toxicidad , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Inmunohistoquímica , Inyecciones Intraperitoneales , Masculino , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Pliegue de Proteína/efectos de los fármacos , Ratas , Ratas Wistar , Factores de Tiempo , Vacuolas/efectos de los fármacos
11.
Am J Med Genet A ; 146A(4): 459-63, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18203193

RESUMEN

Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant congenital disease characterized by progressive heterotopic endochondral osteogenesis with great-toe malformations. A 617G > A (R206H) mutation of the activin A type 1 receptor gene (ACVR1) has been found in all previously reported patients with FOP. Thus, this is one of the most specific of all disease-associated mutations. We report here on a 62-year-old man with slowly progressive FOP and a novel mutation in ACVR1. He developed difficulty in moving his shoulder since age 10 years due to contraction of the shoulder joint. The symptoms progressed slowly, and he could not walk at age 36 years and was bedridden at 55 years. He also showed rigid spine, baldness, sensorineural hearing loss, and hypodactyly accompanied by abnormal ectopic ossification. Analysis of ACVR1 and its cDNA revealed that the patient is heterozygous for a mutation, 1067G > A (G356D). Typing of SNPs located in the approximately 0.5-Mb region spanning ACVR1 and its neighbor genes suggested that 1067G > A is a de novo mutation. These results give a clue to better understanding of FOP as well as of the mild clinical symptoms in the patient.


Asunto(s)
Receptores de Activinas Tipo I/genética , Miositis Osificante/genética , Mutación Puntual , Secuencia de Aminoácidos , Secuencia de Bases , Análisis Mutacional de ADN , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Homología de Secuencia de Aminoácido
12.
Rinsho Shinkeigaku ; 48(1): 36-42, 2008 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-18386630

RESUMEN

We report a 72-year-old man with eosinophilic myositis (EM). At age 71 he noticed a painful nodule in his left calf. A biopsy (first biopsy) showed marked infiltration of mononucleated cells and necrotic muscle fibers. Several phagocytosed fibers were also seen. He was diagnosed as having myositis. The painful nodule disappeared spontaneously. At age 72, he again had a painful nodule, but this time in his right calf; again, this disappeared spontaneously on the first admission. Just after discharge, he noted painful nodules in the left thigh and right anterior tibial muscles and was again admitted (second admission). Neurological examination revealed mild proximal-dominant weakness in all four extremities but no other abnormalities. Laboratory studies showed elevated creatine kinase (CK) level (38,803 U/l; normal 62-287) and positive Jo-1 antibody, but no eosinophilia. Needle electromyography of the limb muscles showed myogenic patterns. Magnetic resonance imaging of the lower limbs demonstrated several T2-high and gadolinium (Gd)-enhanced lesions. Muscle biopsy (second biopsy) from the left quadriceps femoris showed marked infiltration of eosinophils; he was diagnosed as having EM. Administration of prednisolone was initiated at 60 mg/day and then gradually tapered. After starting treatment with steroids, his muscle weakness gradually ameliorated, CK level dramatically decreased, and the nodules disappeared. Clinically, the patient had developed localized nodular myositis (LNM), but pathologically it was EM without peripheral blood eosinophilia and positive Jo-1 antibody that is occasionally found in polymyositis (PM). Thus, this patient demonstrated overlapping characteristics of EM, LNM, and possibly PM, suggesting that a common mechanism underlay these conditions. As discussed, the involvement of eosinophils in three inflammatory myopathies was indicated.


Asunto(s)
Eosinofilia/complicaciones , Miositis/etiología , Anciano , Anticuerpos Antinucleares/sangre , Biomarcadores/sangre , Creatina Quinasa/sangre , Electromiografía , Eosinofilia/patología , Eosinófilos/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Miositis/diagnóstico , Miositis/tratamiento farmacológico , Miositis/patología , Prednisolona/uso terapéutico , Resultado del Tratamiento
13.
Cell Rep ; 22(1): 123-135, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29298415

RESUMEN

Establishment of precise neuronal connectivity in the neocortex relies on activity-dependent circuit reorganization during postnatal development; however, the nature of cortical activity during this period remains largely unknown. Using two-photon calcium imaging of the barrel cortex in vivo during the first postnatal week, we reveal that layer 4 (L4) neurons within the same barrel fire synchronously in the absence of peripheral stimulation, creating a "patchwork" pattern of spontaneous activity corresponding to the barrel map. By generating transgenic mice expressing GCaMP6s in thalamocortical axons, we show that thalamocortical axons also demonstrate the spontaneous patchwork activity pattern. Patchwork activity is diminished by peripheral anesthesia but is mostly independent of self-generated whisker movements. The patchwork activity pattern largely disappeared during postnatal week 2, as even L4 neurons within the same barrel tended to fire asynchronously. This spontaneous L4 activity pattern has features suitable for thalamocortical (TC) circuit refinement in the neonatal barrel cortex.


Asunto(s)
Axones/metabolismo , Señalización del Calcio/fisiología , Calcio/metabolismo , Neocórtex , Animales , Ratones , Ratones Transgénicos , Microscopía Fluorescente , Neocórtex/citología , Neocórtex/crecimiento & desarrollo , Neocórtex/metabolismo
14.
FASEB J ; 19(2): 255-7, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15548589

RESUMEN

The amyloid beta-protein (Abeta) ending at 42 plays a pivotal role in Alzheimer's disease (AD). We have reported previously that intracellular Abeta42 is associated with neuronal apoptosis in vitro and in vivo. Here, we show that intracellular Abeta42 directly activated the p53 promoter, resulting in p53-dependent apoptosis, and that intracellular Abeta40 had a similar but lesser effect. Moreover, oxidative DNA damage induced nuclear localization of Abeta42 with p53 mRNA elevation in guinea-pig primary neurons. Also, p53 expression was elevated in brain of sporadic AD and transgenic mice carrying mutant familial AD genes. Remarkably, accumulation of both Abeta42 and p53 was found in some degenerating-shape neurons in both transgenic mice and human AD cases. Thus, the intracellular Abeta42/p53 pathway may be directly relevant to neuronal loss in AD. Although neurotoxicity of extracellular Abeta is well known and synaptic/mitochondrial dysfunction by intracellular Abeta42 has recently been suggested, intracellular Abeta42 may cause p53-dependent neuronal apoptosis through activation of the p53 promoter; thus demonstrating an alternative pathogenesis in AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Genes p53/genética , Espacio Intracelular/química , Espacio Intracelular/metabolismo , Degeneración Nerviosa/metabolismo , Fragmentos de Péptidos/metabolismo , Regiones Promotoras Genéticas/fisiología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/fisiología , Precursor de Proteína beta-Amiloide/genética , Animales , Apoptosis/genética , Apoptosis/fisiología , Encéfalo/citología , Encéfalo/metabolismo , Encéfalo/patología , Química Encefálica/genética , Células Cultivadas , Citosol/química , ADN/metabolismo , Femenino , Feto , Cobayas , Respuesta al Choque Térmico/genética , Humanos , Peróxido de Hidrógeno/farmacología , Espacio Intracelular/patología , Leucina/genética , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Mutantes , Ratones Transgénicos , Mutación Missense/genética , Degeneración Nerviosa/patología , Neuroblastoma/patología , Neuronas/química , Neuronas/metabolismo , Fragmentos de Péptidos/fisiología , Presenilina-1 , Regiones Promotoras Genéticas/genética , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Elementos de Respuesta/fisiología , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/biosíntesis , Valina/genética
15.
J Biochem Biophys Methods ; 68(2): 139-43, 2006 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-16769124

RESUMEN

An improved method for Southern DNA and Northern RNA blotting using the Mupid-2 Mini-Gel System is described. We get sharp and clear bands in Southern and Northern blotting after only 30 min short gel electrophoresis instead of the several hours large gel electrophoresis of conventional methods. The high electrical voltage with a pulse-like current of the Mupid-2 Mini-Gel System also allows reduction of the amount of formaldehyde, a harmful reagent, from the gel running buffer in RNA blotting. This minor modification of DNA and RNA blotting technique enables us to perform the complete experimental procedure more quickly economically in less space, than conventional Southern and Northern blotting, as well as using an extremely small amount of formaldehyde in RNA blotting.


Asunto(s)
Northern Blotting , Southern Blotting , ADN/análisis , ARN/análisis , Northern Blotting/métodos , Southern Blotting/métodos , Electroforesis en Gel de Agar/métodos , Humanos , Hibridación de Ácido Nucleico/métodos
16.
Biochem Pharmacol ; 69(3): 503-16, 2005 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-15652241

RESUMEN

Expanded CUG triplet repeats carrying mRNA seem to be responsible for myotonic dystrophy type 1 (DM1). To study the pathogenesis of DM1, we constructed a DM1 cell culture model using a PC12 neuronal cell line and screened flavonoids that ameliorate this mRNA gain of function. The expanded 250 CTG repeat was subcloned into the 3'-untranslated region of the luciferase gene yielding a stable transformant of PC12 (CTG-250). The cytotoxicity of CTG-250 was evaluated by intracellular LDH activity, and the cis-effect by luciferase activity. To find agents that alter CTG-250 toxic effects, 235 bioflavonoids were screened. An increased cis-effect and cytotoxicity were found when CTG-250 was treated with nerve growth factor to induce differentiation. Western blotting with anti-caspase-3 antibody suggested that cell death was caused by apoptosis. Screening analysis confirmed that a flavone (toringin), an isoflavones (genistein and formononetin), a flavanone (isosakuranetin), and DHEA-S prevent both the cytotoxicity and cis-effect of CTG-250 and that a flavanone (naringenin), isoflavone (ononin), and xanthylatin strongly inhibit the cis-effect of CTG repeats. In conclusion, we found that this neuronal cell line, which expresses the CUG repeat-bearing mRNA, showed cis-effects through the reporter gene and neuronal death after cell differentiation in vitro. However, some flavonoids and DHEA-S inhibit both the cis-effect and cytotoxicity, indicating that their chemical structures work to ameliorate both these toxic effects. This system makes it easy to evaluate the toxic effects of expanded CTG repeats and therefore should be useful for screening other DM1 treatments for their efficacies.


Asunto(s)
Sulfato de Deshidroepiandrosterona/farmacología , Flavonoides/farmacología , Expansión de Repetición de Trinucleótido , Empalme Alternativo , Animales , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Fosforilación , ARN Mensajero/toxicidad , Ratas , Relación Estructura-Actividad , Proteínas tau/genética
17.
Ann Clin Transl Neurol ; 2(10): 960-71, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26478896

RESUMEN

OBJECTIVE: To investigate anti-neurofascin 155 (NF155) antibody-positive chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: Sera from 50 consecutive CIDP patients diagnosed in our clinic, 32 patients with multiple sclerosis, 40 patients with other neuropathies including 26 with Guillain-Barré syndrome (GBS)/Fisher syndrome, and 30 healthy controls were measured for anti-NF antibodies by flow cytometry using HEK293 cell lines stably expressing human NF155 or NF186. Four additional CIDP patients with anti-NF155 antibodies referred from other clinics were enrolled for clinical characterization. RESULTS: The positivity rate for anti-NF155 antibodies in CIDP patients was 18% (9/50), who all showed a predominance of IgG4 subclass. No other subjects were positive, except one GBS patient harboring IgG1 anti-NF155 antibodies. No anti-NF155 antibody carriers had anti-NF186 antibodies. Anti-NF155 antibody-positive CIDP patients had a significantly younger onset age, higher frequency of drop foot, gait disturbance, tremor and distal acquired demyelinating symmetric phenotype, greater cervical root diameter on magnetic resonance imaging neurography, higher cerebrospinal fluid protein levels, and longer distal and F-wave latencies than anti-NF155 antibody-negative patients. Marked symmetric hypertrophy of cervical and lumbosacral roots/plexuses was present in all anti-NF155 antibody-positive CIDP patients examined by neurography. Biopsied sural nerves from two patients with anti-NF155 antibodies demonstrated subperineurial edema and occasional paranodal demyelination, but no vasculitis, inflammatory cell infiltrates, or onion bulbs. Among anti-NF155 antibody-positive patients, treatment responders more frequently had daily oral corticosteroids and/or immunosuppressants in addition to intravenous immunoglobulins than nonresponders did. INTERPRETATION: Anti-NF155 antibodies occur in a subset of CIDP patients with distal-dominant involvement and symmetric nerve hypertrophy.

18.
J Neurol Sci ; 221(1-2): 95-7, 2004 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15178221

RESUMEN

Two adult females developed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and psoriasis. Both showed chronic progressive paraparesis and sharply demarcated erythematous scaling plaques on their extremities and trunk. One patient had polymyositis while in the other anti-thyroid antibodies, antinuclear antibodies and SS-A antibody, all autoantibodies, were positive. Both patients were treated by intramuscular injections of interferon-alpha for 2 to 4 weeks, resulting in amelioration of paraparesis. After the therapy psoriasis and polymyositis markedly improved in one patient without any additional therapy, while in the other simultaneous use of topical corticosteroids was effective. This is the first report to describe occurrences of psoriasis in HAM/TSP patients. Although there are several reports indicating interferon-alpha induces or exacerbates psoriasis, our experience suggests that psoriasis associated with HAM/TSP can be successfully managed even during interferon-alpha therapy.


Asunto(s)
Paraparesia Espástica Tropical/complicaciones , Psoriasis/complicaciones , Adulto , Femenino , Humanos , Interferón-alfa/uso terapéutico , Persona de Mediana Edad , Músculo Esquelético/patología , Paraparesia Espástica Tropical/patología , Psoriasis/tratamiento farmacológico
19.
Clin Rheumatol ; 23(2): 160-2, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15045632

RESUMEN

Amyopathic dermatomyositis (ADM) is characterized by the typical cutaneous features of dermatomyositis and minor involvement of the skeletal muscles. A 50-year-old woman had fever, reddening and pain in the distal part of all four limbs, and cutaneous findings such as Gottron's papules and periorbital heliotrope. She showed no muscle weakness or atrophy, and her serum creatine kinase was within the normal range. Electromyography showed no myopathic pattern. Magnetic resonance imaging (MRI) recorded abnormal hyperintensity in the fascia and muscle of the tibialis anterior. A biopsy from the tibialis anterior muscle showed fasciitis and mild myopathic changes with focal perivascular infiltration. This patient also presented with interstitial pneumonitis, although evaluation for malignancy was negative. With steroid therapy, her symptoms and MRI abnormality disappeared within 2 months. This case is therefore considered to be a variant of ADM, presenting as dermato-fasciitis.


Asunto(s)
Dermatomiositis/complicaciones , Fascitis/complicaciones , Músculo Esquelético/patología , Antiinflamatorios/uso terapéutico , Dermatomiositis/tratamiento farmacológico , Dermatomiositis/patología , Fascitis/tratamiento farmacológico , Fascitis/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Prednisolona/uso terapéutico , Resultado del Tratamiento
20.
Rinsho Shinkeigaku ; 44(7): 450-3, 2004 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-15384708

RESUMEN

A 29-year-old woman with benign congenital nemaline myopathy is reported. She did not walk until the age of one year and seven months. Although she acquired the ability to run, she ran very slowly. She first noticed the progression of weakness of the limbs at age 21, and it worsened gradually. On admission, she showed moderate weakness in the face, neck, and four limbs. Serum creatine kinase was elevated to 218 U/l. Needle electromyography showed giant and polyphasic motor unit potentials with a reduced reference pattern in the four limbs diffusely. In muscle biopsy, about 10% of fibers had many small vacuoles, and half of them were rimmed. Modified Gomori trichrome stain revealed nemaline rods in about 20% of both type I and type II fibers. Fibers with large diameter and atrophic ones showed increased acid phosphatase activity. Type I fibers were small, and type II fibers numbered only 2%. We diagnosed her illness as a congenital nemaline myopathy that began in infancy and progressed in adulthood. The increased autophagic activity probably caused the progression of muscle weakness. Moreover, the presence of both nemaline rods and rimmed vacuoles may have contributed to the development of diffuse neurogenic changes seen in electromyography.


Asunto(s)
Electromiografía , Músculo Esquelético/citología , Miopatías Nemalínicas/patología , Vacuolas/patología , Fosfatasa Ácida/metabolismo , Adulto , Autofagia/fisiología , Progresión de la Enfermedad , Femenino , Humanos , Fibras Musculares Esqueléticas/enzimología , Fibras Musculares Esqueléticas/patología , Miopatías Nemalínicas/diagnóstico , Miopatías Nemalínicas/etiología , Miopatías Nemalínicas/fisiopatología
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