Invited. Brain edema development after MRI-guided focused ultrasound treatment

The aim of this study was to investigate a potential technique for image-guided minimally invasive neurosurgical interventions. Focused ultrasound (FUS) delivers thermal energy without an invasive probe, penetrating the dura mater, entering through the cerebrospinal fluid (CSF) space, or harming intervening brain tissue. We applied continuous on-line monitoring by MRI to demonstrate the effect of the thermal intervention on the brain tissue. For this, seven rabbits had a part of their skull removed to create access for the FUS beam into the brain through an acoustic window of 11 mm in diameter. Dura was left intact and skin was sutured. One week later, the rabbits were sonicated for 3 seconds with 21 W acoustic power, and the FUS focus was visualized with a temperature-sensitive T1-weighted MRI pulse sequence. The tissue reaction was documented over 7 days with T2-weighted images of the brain. The initial area of the central low signal intensity in the axial plane was .4 ± .3 mm², and for the bright hyperintensity surrounding the lesion, it was 2.3 ± .6 mm² (n = 7). In the coronal plane, the corresponding values were .4 ± .1 mm² and 3.4 ± .9 mm² (n = 5). The developing brain edema culminated 48 hours later and thereafter diminished during the next 5 days. Histology revealed a central necrosis in the white matter surrounded by edematous tissue with inflammatory cells. In summary, the image-guided thermal ablation technique described here produced a relatively small lesion in the white matter at the targeted location. This was accomplished without opening the dura or the need for a stereotactical device. MRI allowed on-line monitoring of the lesion setting and the deposition of thermal energy and demonstrated the tissue damage after the thermal injury.     

Localization of tissue plasminogen activator mRNA in adult rat brain

The distribution of tissue plasminogen activator (tPA) messenger RNA in rat brain was studied using in situ hybridization with ³⁵S UTP-labeled RNA probes derived from a fulllength tPA cDNA. Sense strand controls produced low, even backgrounds, with small elevations in the hippocampus. Full-length antisense probes produced strong signals over cerebral ventricular ependyma (including ependyma of the subcommissural organ), meninges, blood vessels, and Purkinje cell layer of the cerebellum, as well as strong signals over scattered cells throughout the brain. Some of these scattered labeled cells were large with lightly stained nuclei, while others were small with darkly stained nuclei. The large labeled cells, which were probably neurons, constituted 8% and 8% of cells in the brain stem and neocortex, respectively, and 100% of Purkinje cells. The small cells, which were present in all areas of the brain, constituted 3–11 % of cells in individual brain areas.     

The use of a priori knowledge to quantify short echo in vivo 1h mr spectra

In vivo ¹H MR spectra of the prefrontal cortex acquired with the stimulated echo acquisition mode (STEAM) TE = 20 ms sequence were quantified to determine relative levels of cerebral metabolites. A priori knowledge of spectra from individual metabolites in aqueous solution was incorporated into a frequency domain quantification technique. The accuracy and precision of modeling these metabolites were investigated with simulated spectra of varying signal-to-noise ratios (SNRs) and relative metabolite levels. The efficacy of modeling in vivo data was tested by quantifying 10 repeated measures of two consecutively acquired in vivo spectra (an 8?cm³ volume of interest (VOI) and a 4?cm³ VOI positioned within the 8?cm³ VOI) on the same normal subject. The differences in levels of glutamate (Glu), phosphocreatine plus creatine (PCr+Cr) and choline-containing compounds (Cho₁ between spectra from the 8? and 4?cm³ VOIs corresponded with the expected differences observed in the proportions of gray matter within the VOIs (estimated from ¹H images). Correcting for the T₁ and T₂ relaxation, the estimated concentrations of N-acetylaspartate, PCr+Cr, Cho₁, Glu, and glutamine were consistent with previous in vivo and in vitro reports.     

育龄期妇女输卵管结扎后上皮细胞超微结构的改变

应用扫描电镜观察9位育龄期妇女正常和结扎后的输卵管上皮。结果表明:在输卵管结扎疤痕两侧各0.5cm处,粘膜上皮细胞的纤毛大量扭曲和粘连,局部上皮纤毛和微绒毛脱落,细胞形态不规则,而在距输卵管结扎疤痕两侧各1.0cm处,上皮细胞的纤毛和微绒毛形态和结构均正常。表明输卵管结扎后上皮的超微结构变化,使卵细胞输送功能丧失,可能是输卵管复通术后不孕的重要原因。因此,施行输卵管复通术时,输卵管疤痕切除的范围应不少于疤痕两侧各0.5cm,以提高输卵管复通率。此外,发现输卵管小孔仅位于输卵管积水处粘膜的分泌细胞间,可能与输卵管浆膜下毛细淋巴管相沟通,与引流输卵管积水有关。在输卵管积水处粘膜的表面纤毛细胞的纤毛大量脱落,微绒毛增生,许多纤毛细胞转变为分泌细胞。提出了形成输卵管积水新的发病机理。     

Characterization of glial subpopulations in cultures of the ovine central nervous system

The cellular composition and in vitro development of glial cultures derived from the rat CNS has been well studied. However, less information is available on similar cultures from other species, particularly higher mammals. To study ovine glial development in vitro, cultures from 50-day fetal to adult animals were characterized with various immunocytochemical markers, which are frequently used to define neural cell subsets in rat cultures. As in rats, both A2B5+ and A2B5- astrocytes can be identified in ovine cultures. However, ovine A2B5+ and A2B5- could not be reliably differentiated by their morphology, which was more influenced by whether the cells were in serum-free or serum-containing media than by their A2B5-positive or -negative status. In addition, ovine A2B5+ astrocytes were present in cultures from early fetal brain before the development of identifiable oligodendrocytes, unlike rat type II astrocytes, which develop only after the appearance of oligodendrocytes. An A2B5+ cell, morphologically similar to the rat 02-A cell, can be found in cultures from fetal ovine cerebrum or cerebellum. A2B5+/glial fibrillary acidic protein (GFAP)- cells in cultures from 100- to 115-day ovine cerebellum appeared to differentiate into A2B5+ astrocytes in serum-containing media. However, in serum-free media, although the A2B5+ cells assumed a more "oligodendroglial-like" morphology, they did not express galactocerebroside or myelin basic protein, suggesting that these cells may not be bipotential as is the rat 02-A cell. Oligodendroglial differentiation was not induced by treatment with dibutyryl cyclic AMP or insulin-like growth factor I. Many cells in cultures from a variety of fetal ages did not label with any of the immunocytochemical markers used, suggesting the need for more cell-type-specific markers to identify neural cell subsets in higher mammals.     

Decreased antibody-dependent cellular cytotoxicity in minimal change nephrotic syndrome

Secondary IgG response to a tetanus toxoid booster and in vitro measurement of immunoglobulin synthesis, antibody-dependent cellular cytotoxicity (ADCC) and -interferon (IFN-) production were evaluated in 20 healthy controls and in 17 children with minimal change nephrotic syndrome (MCNS), during the acute nephrotic phase and 6 months after remission. Defective responses were observed in all but IFN- production during the acute nephrotic phase; these improved with disease remission. There was a significant correlation between decreases in vitro IgG production and ADCC reaction. These data indicate that defective antibody production is associated with decreased ADCC during the acute nephrotic phase of MCNS.     

基于网络药理和实验验证探究中药通过健脾作用治疗白细胞减少症的作用机制

摘要 目的 运用数据挖掘、网络药理学和实验验证探讨中药通过健脾作用治疗白细胞减少症的用药规律、药效物质基础及潜在的作用机制。方法 在中国知网、万方数据知识服务平台、维普网和PubMed数据库中检索健脾中药复方治疗白细胞减少症的临床文献,运用古今医案云平台在线分析软件和SPSS Modeler 18 统计分析软件寻求核心药物组;利用中药系统药理学数据库和分析平台（TCMSP）、GeneCards数据库、OMIM数据库检索、Cytoscape3.7.2软件、STRING数据库获取关键基因和主要有效成分,利用Metascape进行基因本体（GO）功能富集分析和京都基因与基因组百科全书（KEGG）通路富集分析;采用MTT法检测细胞增殖率,采用qPCR法检测关键基因信使核糖核酸（mRNA）水平表达。结果 共筛选得到90篇有效文献,共计91首中药复方,党参-当归-黄芪为核心药物组合。肿瘤坏死因子（TNF）、白细胞介素-6（IL-6）、白细胞介素-1β（IL-1β）、白细胞介素-10（IL-10）、JUN为核心靶点,槲皮素、木犀草素、山奈酚、芒柄花素、豆甾醇为主要有效成分,其主要作用机制可能通过癌症的途径、TNF信号通路、p53信号通路等来实现。健脾中药黄芪、党参、当归提取物和有效成分芒柄花素、槲皮素对人单核细胞白血病细胞（THP-1）具有促进增殖作用,芒柄花素对化疗诱导的THP-1细胞生长具有促进增殖的作用,芒柄花素能够抑制炎症细胞因子IL-6、IL-1β、TNF-α和刺激抗炎因子IL-10、原癌基因JUN的分泌。结论 初步揭示黄芪等多种中药通过多成分、多靶点发挥健脾作用,参与抗肿瘤、抗炎、免疫调节等相关信号通路,治疗白细胞减少症。     

家兔输卵管结扎术后黄体的形态变化

将27只雌性家兔随机分为五组,即Pomeroy法扎管组;Uchida法扎管组;结扎子宫动脉组;结扎卵巢动脉组和假手术组。术后4～10周合笼交配。交配后第八天取黄体做光镜和透射电镜观察。结果:Uchida法扎管后黄体的形态正常;Pomeroy法扎管和结扎子宫动脉后黄体的形态有轻微改变;结扎卵巢动脉后黄体的形态有明显改变。研究结果对探讨“扎管后综合征”的发生机制具有一定的意义。     

Local axonal trajectories in mouse barrel cortex

Summary Quantitative studies were made of the distribution of labeled intracortical axons after focal injections of horseradish peroxidase (HRP) into mouse barrel cortex, in vitro. The pattern of labeled fibers was compared to that of labeled cell bodies with respect to the barrel map in layer IV. We analyzed 4 cortices with injections in supragranular layers and centered above a single barrel row. Computer microscope/image analysis routines were used to collect the data and to perform various statistical analyses on them. The distributions of both labeled cells and fibers in layer IV and in the infragranular layers show strong connectional tendencies between barrels representing a whisker row. This result is consistent with single unit recordings from barrel cortex. Fiber labeling is more widespread than cell body labeling in layer IV. In addition, the fibers show a directional bias into the adjacent anterior barrel row (e.g., C D, D E). In earlier 2-deoxyglucose (2-DG) studies of behaving animals, the anterior barrel rows were more heavily labeled; inter-row projections are therefore predominantly from less active to more active barrel columns. These data show that labeled fiber distribution differs from the distribution pattern of labeled cell bodies. The findings indicate that integration of information between whisker rows within barrel cortex involves asymmetrical connections within layer IV and infragranular layers.