Phosphorylation and dephosphorylation of distinct isoforms of the heavy neurofilament protein NF-H

Summary 1. Previous immunohistochemical studies led to the suggestion that distinctly phosphorylated neurofilament isoforms exist in different types of neurons. We have recently examined this hypothesis by direct biochemical experiments, which revealed that the heavy neurofilament protein NF-H of bovine ventral root cholinergic neurons is more acidic and markedly more phosphorylated than that of bovine dorsal root neurons.2. In the present study we employed this system to study the degree to which distinctly phosphorylated NF-H isoforms differ in the extents to which they can be phosphorylated and dephosphorylatedin vitro. This was performed utilizing alkaline phosphatase and protein kinase PK40^ERK, which is specific to serines of Lys-Ser-Pro (KSP) repeats. The results obtained reveal that:3. The more extensively phosphorylated ventral root NF-H is dephosphorylated more rapidly than dorsal root NF-H.4. Ventral root NF-H and dorsal root NF-H in their native form are both poor substrates of PK40^ERK.5. Following dephosphorylation, ventral root and dorsal root NF-H are phosphorylated extensively and differentially by this kinase. Under these conditions, PK40^ERK catalyzes the incorporation of, respectively, 4.2±1.3 and 2.8±0.6 mol of phosphate per molecule of ventral root NF-H and dorsal root NF-H. The ratio of phosphates incorporated into ventral root NF-H to those incorporated into dorsal root NF-H is 1.46±0.17.6. These findings support the hypothesis that different classes of neurons contain distinctly phosphorylated neurofilaments and show that ventral root and dorsal root neurons are a useful model system for studying the distinct characteristics of neurofilament phosphorylation in different types of neurons.     

An embryological study of ventralization of dorsal structures in the tail of medaka (Oryzias latipes) Da mutants

In adult Da ( double anal fin ) mutants of medaka ( Oryzias latipes ), structures such as the dorsal fin and the dorsal half of the caudal fin are ventralized in adult fish. However, there have been few embryological studies of the development of mutant phenotypes except those of the caudal fin. In this study, development of mutant phenotypes of the tail where they typically develop was examined morphologically at various stages of embryogenesis. The arrangement of melanocytes along the dorsal midline, the shape of the dorsal fin fold, and the shape of the dorsal myotome exhibited a ventral pattern in the tail at various embryonic stages in Da mutants.     

Functional and pathophysiological models of the basal ganglia

Because of new data, anatomical and functional models of the basal ganglia in normal and pathological conditions (e.g. Parkinson's and Huntington's diseases) have recently come under greater scrutiny. An update of these models is clearly timely, taking into consideration not only changes in neuronal discharge rates, but also changes in the patterning and synchronization of neuronal discharge, the role of extrastriatal dopamine, and expanded intrinsic and input/output connections of these nuclei.     

The uptake of organic molecules by the ventral tube of Tomocerus flavescens (Tullberg, 1871) (Insecta: Collembola)

The net influx of water-soluble organic molecules by the ventral tube of Tomocerus flavescens, a soil litter-inhabiting Collembolan, was investigated. The following substances were tested: [¹⁴C]urea, [¹⁴C]glycerol, [¹⁴C]erythritol, [¹⁴C]l-leucine, [¹⁴C]d-glucose, [³H]inulin. The animals were exposed to moist filter paper containing a specific test solution. When they evert their ventral-tube vesicles, they absorb water and solutes through the cuticle and the transport epithelium into the body haemolymph. Contamination by radioactive substances and oral solute uptake was avoided by an experimental device. It is evident that the uptake rates decrease with increasing molecular mass especially in a range of 100–200. Further, the rates correlate with the radius of hydrated molecules and their lipid solubility. Significant differences in urea uptake have been shown for animals less than 10 days in culture (“field” animals) and more than 10 days in culture (“laboratory” animals). Whether changes in cuticle permeability could be affected by abrasion is discussed. There is a high deviation amongst uptake values in all experimental series. It seems probably that, besides individual differences caused by abrasion, the animals differ physiologically, e.g. during the moulting cycle and seasonally. A nutritive function of the ventral tube seems to be unlikely. Calculation reveals that the absorbed glucose provides only 0.013% of the amount the animals need for respiration.     

84 例基于三脚架结构改建的鼻尖综合整形术的临床总结

目的:总结基于鼻翼软骨三脚架结构的改建技术在鼻尖综合整形术中的应用经验。方法:从2012年09月到2015年02月间,共84例求美者在我院进行初次鼻尖综合整形术。3例为男性,81例为女性。年龄20-45岁,平均年龄31.7岁。其中鼻头肥大伴鼻背低平65例,行鼻翼软骨缝合+鼻翼软骨切除+鼻假体+自体软骨帽状移植术;鼻头肥大、鼻背低平伴鼻小柱短小19例,行自体软骨鼻小柱支撑+鼻翼软骨切除+鼻翼软骨缝合+鼻假体植入+自体软骨帽状移植术。结果:84例求美者术后随访1个月-2年,除1例病例鼻头过于肥大,鼻尖形态改善不明显以外,其余求美者鼻额角及鼻尖角度及均较术前有明显改善,鼻小柱短小组的鼻小柱长度也较术前有明显改善。所有病例切口瘢痕均不明显,无明显并发症出现。结论:针对不同鼻翼软骨发育条件下的病人,个性化的应用鼻翼软骨三脚架结构改建的鼻尖综合整形术具有较好的临床效果,须根据不同病人特点选用。     

Serotonin Receptor Changes in Dementia of the Alzheimer Type

Serotonin receptors were assessed in post-mortem brains of control and Alzheimer-type dementia (ATD) patients using ligand binding techniques. Differential losses of serotonin S1 and S2 receptors were present in neocortex, hippocampus, and amygdala of ATD patients, whereas no significant changes were observed in basal forebrain and basal ganglia. Losses of S1 receptors were significantly age-related in the ATD group, suggesting they occurred at a later stage of the disease process. Losses of S2 receptors were considerably greater (with a reduction to 35% of control in temporal cortex) and were not age-related in ATD. Significant correlations were observed within the ATD group between S2 receptor binding and somatostatin immunoreactivity in temporal and frontal cortices. Thus the loss of S2 receptors in ATD may be a relatively early change in the disease process, and may precede the changes in ascending serotonergic neurones.     

家兔延髓腹侧区内注射吗啡对刺激下丘脑诱发室性期前收缩的抑制作用

家免63只,用乌拉坦(700mg/kg)和氯醛醣(35mg/kg)静脉麻醉,三碘季铵酚制动,在人工呼吸下进行实验。用电刺激下丘脑近中线区的方法诱发定性期前收缩(HVE)。双侧延髓腹侧区内微量注射吗啡(5μg 溶于0.5—1μl 中)可抑制 HVE。在双侧延髓腹侧区微量注射纳洛酬(2μg 溶于0.5—1μl 中)能阻断电刺激中缝核尾端或中缝核尾端内微量注射 L-谷氨酸钠(50mmol/L,0.5—1μl)对 HVE 的抑制效应,也能减少或消除刺激腓深神经对 HVE 的抑制作用。上述结果提示,延髓腹侧部阿片受体的激活可抑制 HVE;另外,腓深神经传入冲动也可能通过中缝核尾端激活延髓腹侧区的阿片受体而抑制 HVE。     

The role of activated NLRP3 inflammatory body in acute kidney injury in rats caused by sepsis and NLRP3-TXNIP signaling pathway

ObjectiveThe model of acute renal injury (AKI) induced by sepsis in rats was established by abdominal resection through surgical suture. The activation mechanism of nod-like receptor with pyrin domain containing 3 (NLRP3) inflammatory corpuscle in AKI induced by sepsis was analyzed.MethodsHere, 60 male rats were selected and divided into two groups, including sham-operated group (NO-OPs group, n = 15) and sepsis group (CELP group, n = 45). In order to examine each index of CELP group, four time points (10, 20, 30, and 40 h) were set as control. In NO-OPs group, only abdominal resection through surgical suture was carried out. The expression levels of NLRP3, apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), caspase-1, and the expression level of NLRP3-TXNIP signaling pathway were measured by immunohistochemistry, Western blotting, immunoprecipitation, and mito-TEMPO (a mitochondria-targeted antioxidant) 40 h after operation and 10, 20, 30, and 40 h post-operation in CELP group. Herein, 40 h post-operation in NO-OPs group and 10, 20, 30, and 40 h post-operation in CELP group, peripheral blood samples were collected.ResultsCompared with NO-OPs group, the levels of serum creatinine (Scr) and blood urea nitrogen (BUN) in CELP group were increased (P < 0.05). Compared with NO-OPs group, the expression levels of interleukin-1β (IL-1β), NLRP3, ASC, and caspase-1 in CELP group were increased (P < 0.05). The expression level of TXNIP in renal tubular epithelial cells in rats was up-regulated. There was a positive correlation between TXNIP and NLRP3. The binding of NLRP3-TXNIP signaling pathway could be inhibited by siRNA transfection or mito-TMPO, and the activity of NLRP3 inflammatory bodies could be inhibited as well.ConclusionActivation of NLRP3 inflammatory corpuscles could promote AKI induced by sepsis. Simultaneously, renal injury may lead to the production of mitochondrial reactive oxygen species (mROS), which may induce the binding of TXNIP to NLRP3.     

Multilocus phylogeography and population structure of common eiders breeding in North America and Scandinavia

Aim Glacial refugia during the Pleistocene had major impacts on the levels and spatial apportionment of genetic diversity of species in northern latitude ecosystems. We characterized patterns of population subdivision, and tested hypotheses associated with locations of potential Pleistocene refugia and the relative contribution of these refugia to the post‐glacial colonization of North America and Scandinavia by common eiders (Somateria mollissima). Specifically, we evaluated localities hypothesized as ice‐free areas or glacial refugia for other Arctic vertebrates, including Beringia, the High Arctic Canadian Archipelago, Newfoundland Bank, Spitsbergen Bank and north‐west Norway. Location Alaska, Canada, Norway and Sweden. Methods Molecular data from 12 microsatellite loci, the mitochondrial DNA (mtDNA) control region, and two nuclear introns were collected and analysed for 15 populations of common eiders (n = 716) breeding throughout North America and Scandinavia. Population genetic structure, historical population fluctuations and gene flow were inferred using F‐statistics, analyses of molecular variance, and multilocus coalescent analyses. Results Significant inter‐population variation in allelic and haplotypic frequencies were observed (nuclear DNA F_ST = 0.004–0.290; mtDNA Φ_ST = 0.051–0.927). Whereas spatial differentiation in nuclear genes was concordant with subspecific designations, geographic proximity was more predictive of inter‐population variance in mitochondrial DNA haplotype frequency. Inferences of historical population demography were consistent with restriction of common eiders to four geographic areas during the Last Glacial Maximum: Belcher Islands, Newfoundland Bank, northern Alaska and Svalbard. Three of these areas coincide with previously identified glacial refugia: Newfoundland Bank, Beringia and Spitsbergen Bank. Gene‐flow and clustering analyses indicated that the Beringian refugium contributed little to common eider post‐glacial colonization of North America, whereas Canadian, Scandinavian and southern Alaskan post‐glacial colonization is likely to have occurred in a stepwise fashion from the same glacial refugium. Main conclusions Concordance of proposed glacial refugia used by common eiders and other Arctic species indicates that Arctic and subarctic refugia were important reservoirs of genetic diversity during the Pleistocene. Furthermore, suture zones identified at MacKenzie River, western Alaska/Aleutians and Scandinavia coincide with those identified for other Arctic vertebrates, suggesting that these regions were strong geographic barriers limiting dispersal from Pleistocene refugia.