Evidences for the regulation of GnRH and GTH expression by GnIH in the goldfish, Carassius auratus

Gonadotrophin-inhibitory hormone (GnIH) plays an important role in regulating of reproduction in teleosts. To clarify the mode of action of GnIH on the synthesis of gonadotropin releasing hormone (GnRH) and gonadotrophin (GtH), three GnIHR cDNAs were cloned from the goldfish brain. In situ hybridization results showed that GnIHRs were localized to the hypothalamus and pituitary. In the hypothalamus, GnIHRs were found in the NPP, NPO and NLT, whereas sGnRH neurons were reported to be located, and potentially regulated by GnIH. In the pituitary, only two GnIHRs were observed and they were localized to the PI instead of the adenohypophysis where GtH-expressing cells are localized, suggesting indirect regulation of GtH by GnIH. In vivo, intraperitoneal (i.p.) injections of synthetic goldfish GnIH-II peptide and GnIH-III peptide significantly decreased sGnRH and FSHβ mRNA levels. Only GnIH-II decreased LHβ mRNA levels significantly. In vitro, both GnIH-II and GnIH-III showed no effect on GtH synthesis, but an inhibition of GnRH-stimulated LHβ and FSHβ synthesis was observed when GnIH-III was applied to primary pituitary cells in culture. Thus, GnIH could contribute to the regulation of gonadotropin in the brain and pituitary in teleosts.     

A fetal mouse model of ventricular non-compaction using retinoic acid

ObjectiveTo develop a fetal mouse model of non-compaction of ventricular myocardium (NVM) using All-trans retinoic acid (ATRA).MethodsPregnant mice were divided into blank control group, dimethyl sulfoxide (DMSO) control group and ATRA group. The pregnant mice at 8.5 days after pregnancy were given 70 mg/kg ATRA in DMSO to induce fetal mouse model of NVM in ATRA group. All the hearts were acquired and sliced in short axis from the neonatal mice sacrificed after delivery. Pathological changes were visualized under 40- and 100-fold magnification with Hematoxylin-eosin (HE) staining at different ventricular levels. The criteria for pathological diagnosis of classical NVM were: prominent trabeculations on the endocardial surface and deep intertrabecular recesses communicating with the ventricular cavity and the thickness ratio of non-compacted layer (N) to compact myocardium layer (C) N/C > 1.4. Analysis of variance (ANOVA) and least significant difference (LSD) were used to analyze the differences of three groups, with P < 0.05 considered as significant.ResultsThe typical characteristics of NVM histopathological findings of ATRA fetal mouse were confirmed: compared to the hearts of blank control group (n = 20) and DMSO control group (n = 15), all the hearts of ATRA group (n = 17) showed the obviously thinner compacted layer and the much thicker non-compacted layer. The N/C ratio of left ventricles (LVs) in ATRA group was 2.735 ± 1.634, higher than those in DMSO control group 0.178 ± 0.119 and blank control group 0.195 ± 0.118 with significant difference (F = 32.550, P <0. 0001); N/C ratios of right ventricles (RVs) in the ATRA group were (6.068 ± 4.394), higher than those in the DMSO control group 0.459 ± 0.24 and in the blank control group 0.248 ± 0.182 with significant difference (F = 20.069, P <0.0001). LSD of LVs and RVs showed a significant difference between ATRA and blank control group (P < 0.0001), and between ATRA and DMSO control group (P < 0.0001). LSD showed no significant difference in two control groups of LVs (P = 0.963) and of RVs (P = 0.848) .ConclusionExcess ATRA could be used to induce NVM of fetal mice heart. This animal model might provide a platform for fundamental research of NVM pathogenesis and potential targeting treatment.     

A Review on Resistive Switching in High-k Dielectrics: A Nanoscale Point of View Using Conductive Atomic Force Microscope

Metal-Insulator-Metal (MIM) structures have raised as the most promising configuration for next generation information storage, leading to great performance and fabrication-friendly Resistive Random Access Memories (RRAM). In these cells, the memory concept is no more based on the charge storage, but on tuning the electrical resistance of the insulating layer by applying electrical stresses to reach a high resistive state (HRS or “0”) and a low resistive state (LRS or “1”), which makes the memory point. Some high-k dielectrics show this unusual property and in the last years high-k based RRAM have been extensively analyzed, especially at the device level. However, as resistance switching (in the most promising cells) is a local phenomenon that takes place in areas of ~100 nm², the use of characterization tools with high lateral spatial resolution is necessary. In this paper the status of resistive switching in high-k materials is reviewed from a nanoscale point of view by means of conductive atomic force microscope analyses.     

Characterization and Programming Algorithm of Phase Change Memory Cells for Analog In-Memory Computing

In this paper, a thorough characterization of phase-change memory (PCM) cells was carried out, aimed at evaluating and optimizing their performance as enabling devices for analog in-memory computing (AIMC) applications. Exploiting the features of programming pulses, we discuss strategies to reduce undesired phenomena that afflict PCM cells and are particularly harmful in analog computations, such as low-frequency noise, time drift, and cell-to-cell variability of the conductance. The test vehicle is an embedded PCM (ePCM) provided by STMicroelectronics and designed in 90-nm smart power BCD technology with a Ge-rich Ge-Sb-Te (GST) alloy for automotive applications. On the basis of the results of the characterization of a large number of cells, we propose an iterative algorithm to allow multi-level cell conductance programming, and its performances for AIMC applications are discussed. Results for a group of 512 cells programmed with four different conductance levels are presented, showing an initial conductance spread under 6%, relative current noise less than 9% in most cases, and a relative conductance drift of 15% in the worst case after 14 h from the application of the programming sequence.     

A case of noncompaction of the ventricular myocardium combined with situs ambiguous with polysplenia

A 33-year-old man was admitted to our hospital with chest pain and exertional dyspnea. Two-dimensional echocardiography showed prominent trabeculations and deep intertrabecular recesses, findings consistent with noncompaction of the ventricular myocardium. Thoracoabdominal CT and cardiac magnetic resonance imaging (CMR) revealed situs ambiguous with polysplenia and noncompaction of the left ventricular myocardium. CMR also demonstrated delayed enhancement of the trabeculations located at the apical portion of the left ventricle. The coronary angiogram was normal. This is the first case of noncompaction of the ventricular myocardium associated with situs ambiguous with polysplenia.     

On the origin of the climbing fibers of the cerebellum. An experimental study in the cat with an autoradiographic tracing method

An autoradiographic fiber tracing method was used to determine the contribution of climbing fibers to the cerebellar cortex from the olive and other brainstem precerebellar structures. The morphological characteristics of silver grain accumulations and their location in the molecular or granular layer made it possible to distinguish clearly between climbing fibers and mossy fibers. Three injections of l-leucine were made in the olive to obtain extensive labeling. The projection thus demonstrated is completely crossed and covers large portions of all cerebellar lobules. The course of olivocerebellar fibers was described and it was stressed that some of these fibers make a long rostral loop close to the superior and middle cerebellar peduncles. Injections in the pons, including the nucleus reticularis tegmenti pontis, the lateral reticular nucleus, the spinal nucleus of the fifth nerve, the cuneate and external cuneate nuclei, the descending vestibular nucleus and the nucleus reticularis ventralis, labeled only mossy fibers.It is concluded that, in the cat, the large majority and probably all the climbing fibers originate from the inferior olive. Evidence suggesting that the inferior olive sends a collateral projection to the nucleus reticularis tegmenti pontis was also obtained.     

心室肌致密化不全14例患者的临床特点分析

目的探讨心室肌致密化不全（NVM）的临床特点、治疗及预后。方法回顾性分析2006年8月至2009年5月明确诊断为NVM的14例患者的临床表现及超声心动图、全胸片、心电图等辅助检查结果。结果心功能不全者13例,其中伴有心律失常7例,未有栓塞病例。结论心室肌致密化不全是一种特殊类型的心肌病,其主要临床表现是心力衰竭、心律失常及栓塞。心室肌致密化不全总体预后差,目前尚缺乏有效治疗手段,提高对该病的认识、早期诊断、预防并发症及对症治疗是必要的。     

Anatomy of cerebellar Purkinje cells in the rat determined by a specific immunohistochemical marker

In the present study we have used guanosine 3′: 5′-phosphate-dependent protein kinase antiserum, a specific immunohistochemical marker for cerebellar Purkinje cells, [Lohmann, Walter, Miller, Greengard and De Camilli (1981)Proc. natn. Acad. Sci. U.S.A.78, 653–657], to carry out a detailed analysis of the architecture and projections of Purkinje cells in the adult rat. We have obtained a novel view of aspects of Purkinje cell morphology that were already known and, in addition, we have provided some new information, in particular on the targets of Purkinje cell axons and their pattern of innervation, and on the morphology and course of Purkinje cell axons. Furthermore, we have found a few cells positive for guanosine 3′: 5′ phosphate-dependent protein kinase which are very similar morphologically to Purkinje cells but are located outside of the cerebellar cortex.A unique feature of Purkinje cells is their peculiar monoplanar shape. Not only do their dendritic arbors lie in planes perpendicular to the major axis of the folia, but their axons, including the collaterals, also travel roughly in the same planes. Thus, Purkinje cells can be imagined as lying in longitudinal sheets radiating from the deep cerebellar nuclei. In these sheets, Purkinje cell axons originating from cells located at different rostrocaudal levels of the cortex converge towards the deep cerebellar nuclei without intersecting each other. It is as a result of this precise organization that Purkinje cell axons reach the deep cerebellar nuclei with a mediolateral and rostrocaudal topology that closely reflects the position of their parent cells in the cerebellar cortex. In the subcortical rays of white matter, Purkinje cell axons are interspersed with other axons, being excluded only from longitudinal strips which correspond to the cerebellar raphes. Upon converging towards the deep cerebellar nuclei they segregate into tracts of white matter that alternate with tracts of white matter from which they are excluded. The great majority of Purkinje cell axons terminate in the deep cerebellar nuclei. Recurrent collaterals terminate in close proximity to the Purkinje cell layer. Dense innervation by these axons is found around large interneurons (Lugaro and Golgi cells) and around the Purkinje cell pinceaux. No direct input of recurrent collaterals to Purkinje cell somata is evident in immunostained material.A substantial number of Purkinje cell axons continue beyond the cerebellar nuclei to innervate nearby regions in the brain stem. The most prominently innervated extracerebellar target region is the dorsal part of the lateral vestibular nucleus, which is as heavily innervated by Purkinje axons as the deep cerebellar nuclei are. All the other major parts of the vestibular formation and some adjacent nuclei (including the parabrachial nuclei, the prepositus hypoglossal nucleus and the nucleus of the solitary tract) are innervated to various degrees by Purkinje cells. In these regions heavily innervated cells are interspersed with cells which receive only a moderate degree of innervation and with cells which apparently lack Purkinje cell inputs. Upon reaching the deep cerebellar nuclei, axons destined to extracerebellar targets deviate from the planes of dendritic arborization of their parent cells. They converge into tight bundles which follow an irregular course and intersect each other to reach their targets. Axons travelling in the same bundle often appear to terminate on the same cell.At all target sites Purkinje axons end as varicose terminals which synapse primarily with the perikarya and proximal dendrites of target cells. On the surface of these cells Purkinje cell terminals are often tightly apposed to form a compact mosaic. Both the course of Purkinje cell axons and their pattern of innervation of target cells are consistent with the possibility that contacts between Purkinje cells and their target neurons in the deep cerebellar nuclei and the brain stem are established early in ontogenesis.Purkinje cell-like cells positive for guanosine 3′:5′-phosphate-dependent protein kinase not located in the cerebellar cortex were found predominantly at the dorsal surface of the brain stem and, in particular, in the cortex of the dorsal cochlear nucleus. Only on exception were they found in the cerebellar medulla or in nearby noncortical regions of the brain stem. While some of these cells might be ectopies, the significance of Purkinje cell-like cells in the dorsal cochlear nucleus, a region strikingly similar in architecture to the cerebellar cortex, remains to be established.     

Work Function Adjustment by Using Dipole Engineering for TaN-Al2O3-Si3N4-HfSiOx-Silicon Nonvolatile Memory

This paper presents a novel TaN-Al₂O₃-HfSiO_x-SiO₂-silicon (TAHOS) nonvolatile memory (NVM) design with dipole engineering at the HfSiO_x/SiO₂ interface. The threshold voltage shift achieved by using dipole engineering could enable work function adjustment for NVM devices. The dipole layer at the tunnel oxide–charge storage layer interface increases the programming speed and provides satisfactory retention. This NVM device has a high program/erase (P/E) speed; a 2-V memory window can be achieved by applying 16 V for 10 μs. Regarding high-temperature retention characteristics, 62% of the initial memory window was maintained after 10³ P/E-cycle stress in a 10-year simulation. This paper discusses the performance improvement enabled by using dipole layer engineering in the TAHOS NVM.     

超声心动图对心肌致密化不全的诊断价值

目的探讨超声心动图对心肌致密化不全（noncompaction of the ventricular myocardium,NVM）的诊断价值及临床意义。方法彩色多普勒超声心动图对临床心功能不全及心脏扩大的患者进行多切面的探查,以获取心脏形态、结构及血流信号。结果 28例超声诊断为NVM,其中26例为左心室受累,2例右心室受累,采用詹尼（Jenni）等提出的诊断标准,其内容包括：（1）不合并其他心脏畸形（孤立性心肌致密化不全）;（2）左室部分室壁增厚分为两层,致密层较薄而非致密层较厚;（3）收缩末期非致密化层/致密化层比例〉2;（4）UCG可见心室与小梁隐窝间有血流交通。病变部位：位于心尖部,合并下壁6例,合并侧壁5例,心室壁均未见血栓形成。结论 NVM具有特征性声像图表现,是诊断NVM的可靠首选的检查手段。