Progress in the function of IL1RAPL1, an X-linked nonspecific mental retardation-associated gene / 国际儿科学杂志

IL1RAPL1 gene is one of the genes related to X-linked nonspecific mental retardation(MRX), but its pathogenic mechanism has not been fully clarified.Interleukin-1 receptor accessory protein like 1(IL1RAPL1) is a synaptic adhesion molecule located on postsynaptic membrane.The mutation of IL1RAPL1 gene can lead to the deletion or dysfunction of this protein.Recent studies have shown that the IL1RAPL1 protein regulates dendritic formation and mediates the activity of IL-1β molecules on dendritic morphology.This review describes the latest advances in synaptic and neuronal functions of IL1RAPL1, and summarizes some gene mutations that have been found to be associated with mental retardation(MR)and autism spectrum disorder(ASD), to provide evidence for clinical diagnosis and treatment.

TMEM106B Induces Melanogenesis by Regulating ERK/CREB Signaling Pathway / 中国生物化学与分子生物学报

The TMEM106B protein is a type-II transmembrane protein, which localizes in the endosome and lysosome of dendrites in primary neurons. TMEM106B is essential for maintaining and branching of dendrites, and thus regulates retrograde lysosomal trafficking of dendrites in primary neurons. Mammalian melanocytes are derived from neural cells, while melanosomes are originated from early endosome. However, the function of TMEM106B protein in melanocytes and its potential molecular mechanism in melanogenesis still remain unknown. Recently it was reported that transcription factor EB (TFEB) was the regulator of lysosome synthesis and TMEM106B protein overexpression promoted TFEB translocation into the nucleus. However, MITF (microphthalmia-associated transcription factor) and TFEB regulate each other in melanoma cells in vitro. Here in, plasmid containing gene for TMEM106B overexpression was transfected into melanocytes to investigate the regulation of TMEM106B on melanogenesis. The results showed that TMEM106B protein was localized in the cytoplasm of melanocytes. Compared with the negative control (NC), the mRNA levels of cyclic AMP-responsive element-binding protein (CREB) and MITF, especially CREB, were significantly increased in melanocytes with TMEM106B overexpression P< 0. 001). Western blot analysis showed that the expression of phosphorylated MAP kinase (p-ERK) was apparently increased (P<0.001) and resulted in the up-regulation of melanogenic regulatory proteins, including MITF, tyrosinase (TYR), tyrosinase-related protein-1 (TYRP1) and 2 (TYRP2). Masson-Fontana method showed that TMEM106B influenced the production of melanin in melanocytes. The spectrophotometry assay indicated that the amount of total melanin (ASM) (P<0. 001) and eumelanin (EM) (P<0. 05) were increased in alpaca melanocytes transfected with TMEM106B, while pheomelanin (PM) (P<0. 001) was decreased. These results demonstrated that TMEM106B played a vital role in melanogenesis in melanocytes by regulating ERK/CREB signaling pathway.

Morfología neuronal en el trastorno del espectro autista / Neuronal morphology in autism spectrum disorder

RESUMEN: El trastorno del espectro autista (TEA) abarca un grupo de trastornos multifactoriales del neurodesarrollo caracterizados por una comunicación e interacción social deteriorada y por comportamientos repetitivos y estereotipados. Múltiples estudios han revelado que en el TEA existen disfunciones sinápticas, en la cual la morfología y función neuronal son sustratos importantes en esta patogenia. En esta revisión comentamos los datos disponibles a nivel de anormalidades neuronales en el TEA, enfatizando la morfología de las dendritas, espinas dendríticas y citoesquelo de actina. Las dendritas y espinas dendríticas, ricas en actina, forman la parte postsináptica de la mayoría de las sinapsis excitadoras. En el TEA, los datos obtenidos apuntan a una desregulación en el crecimiento y desarrollo dendrítico, así como una alteración en la densidad de las espinas dendríticas. Lo anterior, se ve acompañado de alteraciones en la remodelación y composición del citoesqueleto neuronal. Para comprender mejor la fisiopatología del TEA, es necesario mayor información sobre cómo los cambios morfofuncionales de los actores que participan en la sinapsis impactan en los circuitos y el comportamiento.

SUMMARY: Autism Spectrum Disorder (ASD) is a group of multifactorial neurodevelopmental disorders, characterized by impaired communication and social interaction skills, and by repetitive and stereotyped behaviors. Multiple studies report that there are synaptic dysfunctions in ASD, in which important substrates such as morphology and neuronal function are involved in this pathogenesis. In this review we discuss the data available at the level of neuronal abnormalities in ASD, and emphasize the morphological aspects of dendrites, dendritic spines, and actin cytoskeleton. Actin-rich dendrites and dendritic spines shape the postsynaptic part of the most excitatory synapses. In ASD, the data points to a dysregulation in dendritic growth and development, as well as an alteration in the density of dendritic spines. This is accompanied by alterations in the remodeling and composition of the neuronal cytoskeleton. In order to better understand the pathophysiology of ASD, further information is needed on how the elements of synaptic morphofunctional changes impact circuits and behavior.

Advances of Nogo-A protein in the mechanism of epilepsy / 中华神经科杂志

The myelin-associated protein Nogo-A was considered to be the axon growth inhibitory factor, which participates in a variety of pathophysiological regulation of nervous system. In recent years, a growing number of studies have shown that Nogo-A protein is closely related to epilepsy by regulating dendritic plasticity, mediating abnormal nerve migration and regulating glial cell activation, etc. This article will review the research progress of Nogo-A in epilepsy in recent years.

The effect of form deprivation on the morphology of retinal ganglion cells in mice / 中华眼底病杂志

Objective To investigate the effects of form deprivation on the morphology of different types of RGC in mice.Methods Sixty B6.Cg-Tg (Thy1-YFP) HJrs/J transgenic mice were randomly assigned to form-deprived group (n=28) and control group (n=32). The right eyes of mice in the form-deprived group were covered by an occluder for 2 weeks as experimental eyes. The right eyes of mice in the control group were taken as control eyes. Before and 2 weeks after form deprivation, the refraction and ocular biometrics were measured; RGC were stained with Bra3a antibody and counted; the morphology of RGC was reconstructed with Neuroexplore software after immunohistochemical staining. The data was compared among experimental eyes, fellow eyes and control eyes by one-way analysis of variance.Results Two weeks after form deprivation, the axial myopia was observed in the experimental eyes (refraction:F=15.009,P<0.001; vitreous chamber depth:F=3.360,P=0047; ocluar axial length:F=5.011,P=0013). The number of RGC in central retina of the experimental eyes was decreased compared with the fellow eyes and the control eyes (F=4.769,P=0.035). The reconstructed RGC were classified into 4 types according to their dendritic morphology. Form deprivation affected all 4 types of RGC but in a different way. Among them, 3 types of RGC were likely contribute to form vision perception. Form deprivation increased the dendrite branches in these types of ganglion cells. However, form deprivation decreasd dendrite segment numbers in both eyes and the intersection and length insholl analyse type 4 ganglion cells which were morphologically identified as ipRGC.Conclusion Form deprivation distinguishingly affects the morphology of different types of RGC, indicating that form vision and non-form vision play different role in myopia development.

Prevention of resveratrol on spatial memory loss of mice induced by calyculin A / 中国病理生理杂志

AIM:To explore the preventive effect of resveratrol on spatial memory loss of the mice induced by intralateroventricular injection of calyculin A (CA).METHODS:Kunming mice of 2 months (n=44) were divided into saline control group, CA group, low-dose resveratrol group and high-dose resveratrol group.The mice in control group and CA group were intraperitoneally injected with equal volume of saline for 21 d, while the mice in low-dose resveratrol group and high-dose resveratrol group were intraperitoneally injected with resveratrol at 5 mg/kg and 10 mg/kg, respectively.At 22 d, CA (4 μL) was injected into the lateral ventricles in CA group, low-dose resveratrol group and high-dose resveratrol group.Morris water maze test was applied to examine the changes of learning and memory abilities of the mice at 27 d.The Golgi staining was used to observe the morphological changes of dendrites and dendritic spines.The hippocampal tissues were homogenated to detect SOD activity.RESULTS:Low-dose resveratrol significantly decreased the escape latency delay induced by CA.Low-dose resveratrol attenuated the decreases in the number of dendrites and the density of dendritic spines of neurons in hippocampal CA1 region induced by CA.High-dose resveratrol but not low-dose resveratrol attenuated the decreased SOD activity induced by CA.CONCLUSION:Resveratrol at low dose attenuates memory loss in the mice induced by CA though preventing dendrite injury.

Changes in Spatial Memory and Depressive-like Behavior in an Aging Rat Model / 中国医科大学学报

Objective To establish an animal model of aging,to observe changes related to cognitive impairment and depression-like behavior,and to explore the mechanisms of the two diseases caused by the model.Methods Male Sprague-Dawley (SD) rats were treated with D-galactose and alchlor;after simultaneous administration of both drugs,their learning and memory abilities were assessed using the Morris water maze test.The depression-like behavioral changes were observed in the forced swimming test.Golgi staining was performed to observe the development of hippocampal neurons;oxidative stress index changes in superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were analyzed in the hippocampus.Results Compared with a control group,rats in the model group showed reduced escape latency (P ＜ 0.05) from the platform in the water maze,reduced residence time on and a reduced number of times passing through the platform (P ＜ 0.05);the real time in the water during the forced swimming test was significantly prolonged (P ＜ 0.01).Golgi staining indicated that dendritic spine density in the hippocampus in model rats was decreased (P ＜ 0.01),as was hippocampus SOD activity (P ＜ 0.05),while MDA levels were increased (P ＜ 0.05).Conclusion We established a new animal model of aging with cognitive impairment and depression.The common disease mechanisms of these two diseases might be related to the destruction of the nervous system during the process of overload caused by free radicals and the resulting metabolic imbalance.

Effect of MITF-M and MITF-A Overexpression on the Dendrtic Formation in Melanocytes / 체질인류학회지

The microphthalmia-associated transcription factor (MITF), has been described as the master regulator of the basic helix-loop-helix leucine zipper family, involves melanogenesis in melanocytes. MITF consists of at least six isoforms, called MITF-M, MITF-A, MITF-B, MITF-C, MITF-H, and MITF-J. Previously, we found that not only MITF-M is expressed in the human hair follicle, but also MITF-A, MITF-C, MITF-H, and MITF-J isoforms are expressed in the skin. The aim of this study was to conform the MITF isoforms expressed in human skin, and investigate novel role of MITF isoforms in the melanocytes. Expression of MITF-M and MITF-A was found in primary melanoctyes and the melanoma cell lines. Interestingly, when MITF-M and MITF-A were overexpressed in the SK-MEL-24 melanoma cells by adenoviral transfection, length of the dendrites, serves as the principal conduit for melanosomes transfer, was significantly increased in the MITF-M overexpressed cells compared with the control group, and number of the dendtrites was significantly increased in the MITF-A overexpressed cells. A signal molecule involve in actin polymerization during dendrite formation, Rac1, was increased in the SK-MEL-24 melanoma cells treated with adenoviral MITF-M and MITF-A vectors. These results suggest that MITF-M and MITF-A induce dendrite formation via Rac1 signaling in the melanocytes.

Dendritic cell costimulatory molecule expression and immunosuppressant intervention / 中国组织工程研究

BACKGROUND:Previous studies on immunosuppression and anti-rejection after organ transplantation mainly focused on effects of T lymphocytes-mediated immune response and immunosuppressive agents on T lymphocytes. Effects of dendritic cel s were unclear. The manifestation and mechanism of immunosuppressive agent effects on dendritic cel s are not identical. OBJECTIVE:To compare the effects of different immunosuppressive agents on expression and function of costimulatory molecules of dendritic cel s, and to explore the mechanism of action of immunosuppressive agents. METHODS:20μg/L rapamycin, 0.04 mg/L mycophenolate, 10μg/L tacrolimus and 1 mg/L cyclosporine A were separately added during bone marrow cel s of C57BL/6 mice were differentiated into dendritic cel s. RESULTS AND CONCLUSION:Flow cytometry results revealed that CD40 expression in each group:rapamycin0.05). One-way mixed lymphocyte reaction results displayed dendritic cel costimulatory T cel proliferation in each group:rapamycin

Effects of repetitive transcranial magnetic stimulation on learning, memory and dendrite morphology in the hippocampus / 中华物理医学与康复杂志

Objective To survey the effects of repetitive transcranial magnetic stimulation (rTMS) on learning,memory and the dendrite morphology of neurons in the CA1 area of the hippocampus in rats with vascular dementia.Methods Thirty-six male SD rats were divided into a control group,a model group and a rTMS group randomly,12 rats in each group.A model of vascular dementia (VaD) was established using the two vessel occlusion method.The rats in the rTMS group were given rTMS treatment.The rats in the other two groups had no therapy.The Morris water maze (MWM) test was used to evaluate the rats' learning and memory abilities on the 30th day after the operation.After the MWM test the dendrite morphology of the pyramidal cells in the CA1 area of the hippocampus was detected after Golgi-Cox staining using light microscopy and the expression of brain-derived neurotrophic factor (BDNF) was detected using immunohistochemistry methods.Results The average MWM escape latency in the rTMS group was shorter than in the model group on the 1 st,2nd,3rd and 4th day.The number of crossings of the platform quadrant in the rTMS group was significantly more than in the model group.The number of branch segments,their total length and the dendritic spine density of pyramidal cell dendrites in the CA1 area of the hippocampus were all significantly lower in the model group than in the control group,but in the rTMS group all these indicators were significantly improvedcompared with the model group.The expression of BDNF in the CA1 area in rTMS group was significantly higher than in the model group.Conclusions rTMS can improve learning and memory in VaD,at least in rats.The mechanism may be associated with rTMS promoting the expression of BDNF in the hippocampus and so improving the dendrite morphology of pyramidal cells.

Noncompetitive antagonists and agonists of glutamate receptor regulate filopodia formation in epidermal cells and melanosome transfer: an experimental study / 中华皮肤科杂志

Objective To investigate the regulatory effect of glutamate signaling pathway on filopodia formation in epidermal cells and on melanosome transfer.Methods Epidermal melanocytes and keratinocytes were isolated from human foreskin and subjected to subculture.After two to three passages of subculture,the melanocytes and keratinocytes were cultured alone or in combination with or without the presence of MK801 (an antagonist of N-methyl-D-aspartic acid (NMDA) receptor) of 100 μmol/L,or NMDA (the activator of NMDA receptor) of 100 μmol/L,for 24 hours.The melanocytes irradiated with UVB at 311 nm served as the control.Scanning electron microscopy was used to observe the appearance of filopodia and dendrites of melanocytes and keratinocytes.Melanosome transfer was visualized under confocal laser scanning microscopy after double immunofluorescent staining.Results Although no obvious changes were observed in the number of dendrites in monocultured melanocytes after treatment with MK801 or NMDA for 24 hours,dendrites became thinner at the terminus and longer with a decrease in the number and length of filopodia after MK801 treatment,but thicker and shorter with an increase in the number and length of filopodia after NMDA treatment compared with untreated monocultured melanocytes.In the coculture system,filopodia were observed between the untreated melanocytes and keratinocytes,and the number of filopodia in melanocytes was larger in the side adjacent to keratinocytes than in the opposite side.Compared with the untreated coculture system,the number of both filopodia connecting melanocytes and keratinocytes and filopodia extending from melanocytes to keratinocytes decreased in the coculture system after treatment with MK801 of 100 μmol/L,but increased after treatment with NMDA of 100 μmol/L,for 24 hours.Melanosomes were found in keratinocytes cocultured with melanocytes without treatment,which were decreased in number after 24-hour treatment with MK801 of 100 μmol/L,but increased in number and even present in keratinocytes nonadiacent to melanocytes after 24-hour treatment with NMDA of 100 μmol/L.Conclusion Glutamate signaling pathway may modulate the transfer of melanosomes from melanocytes to keratinocytes via modulating the appearance of melanocyte dendrites and formation of filopodia.

Neuronal Functions of ESCRTs

The endosomal sorting complexes required for transport (ESCRTs) regulate protein trafficking from endosomes to lysosomes. Recent studies have shown that ESCRTs are involved in various cellular processes, including membrane scission, microRNA function, viral budding, and the autophagy pathway in many tissues, including the nervous system. Indeed, dysfunctional ESCRTs are associated with neurodegeneration. However, it remains largely elusive how ESCRTs act in post-mitotic neurons, a highly specialized cell type that requires dynamic changes in neuronal structures and signaling for proper function. This review focuses on our current understandings of the functions of ESCRTs in neuronal morphology, synaptic plasticity, and neurodegenerative diseases.

Location matters: the endoplasmic reticulum and protein trafficking in dendrites

Neurons are highly polarized, but the trafficking mechanisms that operate in these cells and the topological organization of their secretory organelles are still poorly understood. Particularly incipient is our knowledge of the role of the neuronal endoplasmic reticulum. Here we review the current understanding of the endoplasmic reticulum in neurons, its structure, composition, dendritic distribution and dynamics. We also focus on the trafficking of proteins through the dendritic endoplasmic reticulum, emphasizing the relevance of transport, retention, assembly of multi-subunit protein complexes and export. We additionally discuss the roles of the dendritic endoplasmic reticulum in synaptic plasticity.

Análisis morfométrico del proceso de diferenciación in vitro de neuronas del hipocampo / Morphometric analysis of the differentiation process of hippocampal neurons in vitro

Los cultivos neuronales del sistema nervioso central se han venido usando ampliamente para el estudio de los mecanismos que conducen el proceso de diferenciación neuronal, así como también se han empleado como modelos in vitro para evaluar drogas y desarrollar nuevas terapias, de allí la importancia profundizar en la caracterización de dicho proceso. En este estudio, se prepararon cultivos primarios de células del hipocampo para estudiar los tipos celulares desarrollados, el desarrollo de dendritas y axones, la densidad de vesículas sinápticas y el desarrollo de los conos de crecimiento. Mediante inmunofluorescencia usando anticuerpos y marcadores no inmunológicos, se observaron los cambios experimentados por las estructuras de interés durante diferentes estadios temporales (1-21 días). Observamos una mayor proporción de neuronas sobre glias, desarrollo normal de las redes neuronales (conformadas por dendritas y axones), incremento en la longitud de dendritas y el establecimiento de sinapsis. Las vesículas sinápticas también experimentaron un incremento en su densidad a medida que aumentaba el tiempo de cultivo. Finalmente, se estudiaron los cambios morfológicos de los conos de crecimiento observándose que al inicio del cultivo en su mayoría se encontraban cerrados, pero a medida que maduraban las neuronas la proporción de conos de crecimiento abiertos aumentó. Este trabajo representa un avance en la caracterización morfométrica de los cultivos neuronales puesto que recoge de manera simultánea y cuantitativa los principales aspectos que marcan el proceso de diferenciación neuronal. En este estudio, la medición de estas características morfológicas hizo posible establecer parámetros cuantitativos que ayudarán a distinguir las principales etapas de la diferenciación neuronal.

Neuronal cultures of the central nervous system are widely used to study the molecular mechanisms that rule the differentiation process. These cultures have also been used to evaluate drugs and to develop new therapies. From this we can infer the relevance of performing an extended characterization that involves the main aspects driving such process. To carry out such characterization in the present study we prepared primary cultures from hippocampal cells to study cell identity, development of neuronal processes (dendrites and axons), density of synaptic vesicles and development of growth cones. Using immunofluorescence techniques, specific antibodies and non-immunological probes, we studied the changes experienced by the structures under study during different temporal stages (1-21 days). We observed a major proportion of neurons over glia, normal development of neuronal networks (formed by dendrites and axons), increase in the length of dendrites and axons and establishment of synaptic connections. Synaptic vesicles also showed an increase in their densities as long as the time of the culture progressed. Finally, we studied the morphological changes of the growth cones and observed that those were mostly closed at the beginning of the culture period. As neurons matured we observed an increase in the proportion of open growth cones. This work represents an advance in the morphometric characterization of neuronal cultures, since it gathers the main aspects that outline the neuronal differentiation process. In this study, measurement of these morphological features made possible to establish quantitative markers that will allow establishing more precisely the different stages of neuronal differentiation.

Neuronal activation increases the density of eukaryotic translation initiation factor 4E mRNA clusters in dendrites of cultured hippocampal neurons

Activity-dependent dendritic translation in CNS neurons is important for the synapse-specific provision of proteins that may be necessary for strengthening of synaptic connections. A major rate-limiting factor during protein synthesis is the availability of eukaryotic translation initiation factor 4E (eIF4E), an mRNA 5'-cap-binding protein. In this study we show by fluorescence in situ hybridization (FISH) that the mRNA for eIF4E is present in the dendrites of cultured rat hippocampal neurons. Under basal culture conditions, 58.7 +/- 11.6% of the eIF4E mRNA clusters localize with or immediately adjacent to PSD-95 clusters. Neuronal activation with KCl (60 mM, 10 min) very significantly increases the number of eIF4E mRNA clusters in dendrites by 50.1 and 74.5% at 2 and 6 h after treatment, respectively. In addition, the proportion of eIF4E mRNA clusters that localize with PSD-95 increases to 74.4 +/- 7.7% and 77.8 +/- 7.6% of the eIF4E clusters at 2 and 6 h after KCl treatment, respectively. Our results demonstrate the presence of eIF4E mRNA in dendrites and an activity-dependent increase of these clusters at synaptic sites. This provides a potential mechanism by which protein translation at synapses may be enhanced in response to synaptic stimulation.

Narrow-band ultraviolet-B(311 nm)regulates dendrite formation in cultured B16 melanoma cells / 中华皮肤科杂志

Objective To investigate the effect ofnarrow-band ultraviolet-B(NB-UVB)(311 nm)on dendrite formation in B16 melanoma cells.Methods B16 melanoma cells were irradiated with various doses of NB-UVB(0,25,50,100,200,300 mJ/cm2).Atier additional culture of varying durations,irradiated cells were harvested and subjected to the observation of morphological changes and cell cytoskeleton F-actin microfilaments by phase contrast microscopy and laser scanning confocal microscopy(LSCM).respectively,and to the detection of cell proliferation bv MTT colorimetric assay.Pull down assay was performed to detect the activity of GTP-RhoAA and GTP-Rac1 in B16 cells before and after UVB irradiation.Results Twenty-four hours after irradiation with UVB of 100 mJ/cm2.an increase was observed in the cell body of B16 cells which appeared in sphericity,as well as in the number of dendrites(P＜0.01)which showed a branch-like appearance.compared with non-irradiated cells which had 2-3 dendrites and obscure branches.LSCM revealed that F-actin microfilaments in B16 cells were well organized with clear textures before irradiation;after irradiation wim NB-UVB of 100 mJ/cm2.stress fibers were disassembled and disrupted and the texture became unclear,which was observed as early as 30 minutes and became more and more evident,and at 6 hours the stress fibers displayed a clumping appearance with obscure textures.Following the irradiation with NB-UVB of 100 mJ/cm2,the expression level of GTP-Rac 1 protein increased at l 5 minutes,and.at 30minutes,reached 2 times of that observed in nonirradiated cells,then decreased a liale,but still remained elevated at 60 minutes and 120 minutes,compared to unirradiated cells;meanwhile.the level of GTP-RhoA dropped a little at 30 minutes,then gradually increased and,at 120 minutes.reached 1.6 times of that observed in unirradiated cells.Conclusion Narrow-band UVB(311 nm)can promote dendrite formation.likely via regulating the expression of GTP-Racl and GTP-RhoA in B16 melanoma cells.

Intoxicação experimental por Ipomoea asarifolia (Convolvulaceae) em caprinos e ovinos / Experimental poisoning by Ipomoea asarifolia (Convolvulaceae) in goats and sheep

Ipomoea asarifolia causa uma síndrome tremorgênica em ovinos, caprinos, bovinos e búfalos. Este experimento teve como objetivos determinar a toxicidade para caprinos de I. asarifolia verde, colhidas nas épocas de chuva e de estiagem, e da planta seca triturada, determinar a toxicidade da planta para ovinos, e determinar se o princípio ativo da planta é eliminado pelo leite em doses tóxicas para os cordeiros. No primeiro experimento a planta fresca colhida na época de estiagem e na época de chuvas foi administrada a 16 caprinos. A planta colhida na estiagem foi tóxica na dose diária de 5 e 10g por kg de peso animal (g/kg). A planta colhida na época de chuva foi tóxica na dose diária de 20 e 30g/kg, demonstrando que a planta é mais tóxica durante o período seco. A planta seca, colhida na época de estiagem foi administrada a 9 caprinos em doses diárias de 1.7, 2, 3.4 e 5.1g/kg. Doses de 3, 4 e 5.1g/kg causaram sinais clínicos, demonstrando que a planta mantém a toxicidade após a secagem. A planta fresca colhida na época de estiagem e na época de chuvas foi administrada a 10 ovinos. A planta colhida na estiagem foi tóxica na dose diária de 5g/kg e na época de chuva foi tóxica nas doses de 10 e 20g/kg. Estes resultados sugerem a maior susceptibilidade dos ovinos à intoxicação do que os caprinos. Como alguns produtores mencionam que cordeiros lactentes que não estão pastando se intoxicam através do leite, I. asarifolia foi administrada diariamente nas doses de 2.5, 5 e 10g/kg a 5 ovelhas, a partir do dia do parto (2 ovelhas), do último dia de prenhez (1 ovelha) e 60 dias antes da parição (2 ovelhas). As ovelhas, mas não os cordeiros, apresentaram sinais clínicos, sugerindo que o princípio ativo da planta não é eliminado no leite ou colostro em doses tóxicas para os cordeiros. Em um ovino eutanasiado não foram observadas lesões macroscópicas nem histológicas. Os achados ultra-estruturais mais significativos foram encontrados nos dendritos das...(AU)

Ipomoea asarifolia causes a tremogenic syndrome in sheep, goats, cattle and buffaloes. The objectives of the experiments were (1) to determine the toxicity to goats of fresh I. asarifolia collected during the raining and the dry season, and the toxicity of the dried plant, and (2) to determine the toxicity of the plant to sheep, and if the active principle is eliminated through the milk. In the first experiment the plant collected in the dry season and in the raining season was fed to 16 goats. The plant collected during the dry season caused clinical signs at the daily doses of 5g and 10g/kg body weight. The plant collected during the raining season was toxic at daily doses of 20g and 30g/kg, indicating that the plant is more toxic during the dry season. The plant collected in the dry season and dried was fed to 9 goats at doses of 1.7g, 2.0g, 3.4g, and 5.1g per kg. Daily doses of 3.0g, 4.0g and 5.1g/kg caused clinical signs, showing that the plant maintains its toxicity after being dried. In the second experiment the fresh plant collected in the dry and in the raining season was fed to 10 sheep. The plant collected in the dry season was toxic at the dose of 5g/kg, and the plant collected in the raining season was toxic at the doses of 10g and 20g/kg. The experimental results suggest that sheep are more susceptible to the poisoning than goats. As some farmers mentioned that suckling non-grazing lambs are poisoned by milk ingestion, I. asarifolia was fed at daily doses of 2.5g, 5.0g and 10g/kg for variable periods to 5 sheep from the day of parturition (2 sheep), after the last day of pregnancy (1 sheep) and 60 days before parturition (2 sheep). The sheep but not the lambs showed clinical signs of intoxication suggesting that the active principle is not eliminated through the milk at doses toxic for the lambs. In one euthanized sheep no gross or histologic lesions were detected. The main ultra-structural findings were found in Purkinje...(AU)

Study on abnormal dendrite of retinal ganglion cells in diabetic rats / 中华眼底病杂志

Objective To observe the morphological changes of dendrite and soma in retinal ganglion cells (RGCs) which subsisted in early diabetic rats. Methods The RGCs of 3-months-course diabetic rats and coeval normal rats were marked by gene gun techniques. To collect RGCs photographs by Leica microscope with Z axis and CCD camera;to observe the changes of diameter, variance of structural features in dendritic field and somata after classification which according to the size and morphology. Thy-1 antibody marks on the retinal RGCs, taking a photograph under fluorescent microscope, counting the changes of retinal RGCs density in early diabetic rat. Results In three-month diabetic rats, the density of retinal RGCs was decreased obviously. Morphological changes of RGCs in the dendritic fields were observed with gene gun technique. There was no severe variation in all kinds of the bole of cell dendrite,in which some only showed crispation partially and sparseness also twisting in the dendritic ramus. The mean diameter of dendritic field and soma in class A of diabetic rats was (401±86)μm, the mean diameter of dendritic field in control group was (315±72) μm,compared with each other, there is statistically significant differences (t=21. 249, P<0. 001), the mean diameter of soma in class A of diabetic rats was (24±6) μm, the mean diameter of soma in control group was (22±5) μm, compared with each other,there is no statistically significant differences (t= 0. 927,P>0.05); the mean diameter of dendritic field and soma in class B of diabetic rats were (170±36). (14±2) μm respectively, in control group were (165±36), (16±2) μm, the mean diameter of dendritic field and soma in class C of diabetic group were (265±78),(17±5) μm respectively, in control group were (251±57),(17±4) μm , compared with each other,there are on statistically significant differences (t=1.357,0.798,0. 835,1.104 ,P>0.05). ConclusionsIn short-term diabetes, the survived RGCs show good plasticity in adult diabetic rats, especially in class A. The changes of dendrites were more sensitive than the soma, which could be the leading index of themorphologic changes of RGCs in the early stage. The good plasticity showed by the RGCs and the time window from changing in dendrite to cell death provide us many evidences not only for the research but also for the nerve protection in clinic.

Dendrite morphological characteristics during degenerative process of retinal ganglion cells in royal college surgeons rats / 第三军医大学学报

0.05).The diameter of dendrite branching at the first level of ? subtype of RGCs was markedly increased by 0.44 ?m on the 60th day compared with on the 21st day during the degenerative process of RCS-P+ rats(2.02?0.17 vs 2.66?0.11 ?m,P

CYTOLOGY OF MAGNOCELLULAR NEUROSECRETORY NEURON OF HYPOTHALAMUS IN RATS / 西安交通大学学报(医学版)

By means of chromalum-hematoxylin and thiosulfate aldehydefuchsin stains the magnocellular neurosecretory neuron of the rat hypothalamus was studied. The cell body of neuron containing various amounts of secretory granules was large in size, with a variety of shapes. The axon of neuron showed an beaded appearance; only one in each neuron was very fine in diameter and left hypothalamic nuclei to form the hypothalamo-neurohypophyseal tract. The dendrite, in general, thicker than the axon, did not project outside of the nucleus. Many of the thick short dendrites did not contain secretory granules or only few secretory granules. The thick processes with more secretory granules were considered as dendritic processes. A number of axons and thick processes containing secretory granules also contacted with the endothelium of vessels and the ependyma of the third ventricle. In addition, a group of magnocellular secretory neurons were found in the sub-choroid plexuses of the lateral ventricle.