Characterization of ramified microglia in tissue culture: pinocytosis and motility

Functional properties of ramified microglia were investigated in primary cultures of rat cerebral cortical cells. These microglia could be readily identified in both fixed and living cultures through previously established features. Based on their destruction by 5 mM L-leucine methyl ester, a high level of intrinsic endocytotic activity was established. When cultures were incubated with fluorescent latex beads to assess phagocytosis, little or no such activity was exhibited by ramified cells. However, when cultures were incubated with dyes or other soluble tracer compounds, these cells always exhibited labeling. This labeling was selective for ramified microglia in the cultures and was demonstrated using a variety of compounds, including trypan blue, lucifer yellow, horseradish peroxidase (HRP), and India ink. Intracellular label could be observed in vesicular structures; this localization corresponded to an active cellular process. Also, cellular labeling was inhibited by the presence of colchicine. These features supported the inference that the labeling was attributable to pinocytosis, and this process appeared to account for the vast majority of endocytotic activity in the ramified microglia. Possible physiological significance of this pinocytotic activity was indicated by the accumulation of various neurotransmitters/modulators: gamma-aminobutyric acid and vasoactive intestinal polypeptide (VIP). Ramified cells in these cultures have been previously noted to exhibit a constant and rapid pattern of motility, which was consistently observed here through time-lapse video recording; pinocytosis and rapid motility were shown to concur in individual cells. Based on their high intrinsic pinocytotic activity and pattern of cellular motility, the ramified microglia specifically are suggested to serve a constitutive function of fluid cleansing within the interstitial spaces of brain tissue.     

Guillain–Barré syndrome with marked pleocytosis or a significant proportion of polymorphonuclear granulocytes in the cerebrospinal fluid: neuropathological investigation of five cases and review of differential diagnoses

In cases with otherwise clinically typical Guillain-Barré syndrome (GBS), pronounced cerebrospinal fluid (CSF) pleocytosis or the mere presence of CSF-polymorphonuclear granulocytes should alert the physician to consider alternative diagnoses. Therefore, we retrospectively studied the neuropathology of central and peripheral nervous system in two cases with a CSF cell count of more than 50/microl and in three cases with a significant proportion of polymorphonuclear granulocytes in the CSF sediment. All cases fulfilled the required criteria for the diagnosis of GBS, the duration from onset to death ranged from 4 to 100 days. Neuropathological investigations included routine staining procedures and immunohistochemistry for antigens of glial and haematopoetic cells as well as for products of relevant neurotropic viruses. Demyelinating polyradiculitis was present in four cases, in one patient with a survival time of 4 days the type of damage to myelinated fibres was unclassifiable. In the central nervous system a consistent finding was diffuse activation of microglia, only one case showed mild meningeal and lower brainstem inflammation. Viral products were generally absent. In summary, the neuropathological findings confirm that marked CSF pleocytosis or the presence of polymorphonuclear granulocytes does not rule out the diagnosis of GBS.     

急性白血病血浆及脑脊液D-dimer测定的临床意义

目的 探讨D-dimer(DD)在中枢神经系统白血病及急性白血病诊断、治疗中的价值。方法 采用ELISA法检测54例急性白血病(AL)患者脑脊液(CSF)DD水平，并对其中伴中枢神经系统白血病(CNSL)22例进行动态观察，同时检测7例上呼吸道感染，9例贫血患者CSFDD水平作对照。结果 CNSL组明显高于非中枢神经系统白血病(NCNSL)组及对照组。22例CNSL患者鞘内注射化疗药后。20例达完全缓解(CR)，DD值明显下降。2例无效者，CSFDD维持于较高水平。1例缓解后再次复发者，CSFDD含量再次升高。1例患者在CSF常规、生化确诊CNSL之前，CSF D-dirner已有改变。CNSL组CSFDD含量与CSF压力、白细胞数、蛋白含量均无明显相关关系。结论 DD对CNSL早期诊断、疗效观察、预后估计很有价值。     

Plasma atrial natriuretic peptide (ANP) concentration and fluid balance during rapid intravenous saline infusions in camels

Human muscle samples were obtained with the percutaneous biopsy technique. The samples were membrane-hyperpermeabilized (skinned) using a chemical or freeze-drying technique. Short single fibre segments were dissected from the sample, transferred to an experimental chamber, connected to a force transducer and manipulator, and exposed to temperature-controlled solutions. The force generating-capacity, the sensitivity of the contractile apparatus to calcium and the caffeine threshold for calcium release from the sarcoplasmic reticulum could be studied in the short muscle fibre segments obtained from man with the percutaneous muscle biopsy technique. The average length of the fibre segments between the connectors was 0.44±0.21 mm. Thus, detailed studies of the contractile machinery can be made on human skinned muscle fibres with only minimal discomfort to the patient or subject during biopsy, which should be useful in studies of neuromuscular disease, muscle plasticity or in applied physiology.     

Soluble Fcγ receptors in periodontal lesions

Soluble Fcγ-binding components were detected in gingival fluid from periodontal lesions by incubation with biotinylated human Fcγ fragments. FcγIII receptor was identified by incubation of gingival fluid with monoclonal antibody. Sodium dodecyl sulfate-polyacrylamide gel electophoresis and Western transfer showed that most of the Fcγ-binding components had minimal mobility in a 4–15% gradient gel under nonreducing conditions. Under reducing conditions, the main band of Fcγ-binding components in gingival fluid migrated corresponding to protein A of 49 kDa. The pattern of Fcγ-binding components was similar in serum and gingival fluid except for the observation in gingival fluid of Fcγ-binding components migrating like standard proteins of 19 to 20 kDa, a size that corresponds to the polypeptide part of FcγII receptor and FcγIII receptor.     

Adenosine protects ultrastrueture of isolated rat lungs against fat emulsion injury

In isolated rat lungs subjected to fat emulsion damage, a model simulating adult respiratory distress syndrome, we have previously reported that adenosine (ADO) reduces pulmonary vascular resistance (PVR) and the fluid filtration rate (FFR). In the present study the aim was to examine morphologically this effect of ADO. Two groups of isolated rat lungs were subjected to the injury. Marked and significant differences were found between the groups; in lungs not given ADO, FFR and airway pressure were higher and, as evaluated by electron microscopy, the endothelial lining was thin and partly disrupted. The epithelial cells of the alveolar walls were also partly disrupted and the alveolar septa were split enclosing interstitial edema. In lungs receiving ADO from the onset of exposure to fat emulsion, FFR was lower and ultrastructure did not differ from non–injured non–treated controls perfused for the same length of time.     

经鼻内窥镜脑脊液鼻漏修补术

目的 :探讨经鼻内窥镜修补脑脊液鼻漏的操作技巧及疗效。方法 :经鼻内窥镜手术修补脑脊液鼻漏 12例 ,在鼻内窥镜直视下寻找漏口 ,处理漏口周围黏膜 ,应用肌浆、鼻中隔和中鼻甲黏膜瓣、明胶海绵及EC耳脑胶或生物蛋白胶等修补漏口 ,用湿润烧伤膏油纱条填塞鼻腔 ,术后 4～ 10d抽取纱条。结果 :12例脑脊液鼻漏均 1次修补成功。结论 :经鼻内窥镜修补脑脊液鼻漏具有微创、安全、复发率低等优点。     

正常中脑导水管脑脊液流动磁共振定量研究

目的 :运用磁共振相位对比电影法非侵袭性测量中脑导水管脑脊液流动方向、流速及流量改变情况。方法 :测量 15例正常志愿者 (年龄 2 1～ 4 7岁 ,平均 31 4岁 )中脑导水管脑脊液流动情况 ,在正中矢状位T1WI图像上选择垂直于导水管层面 ,编码速率 2 0cm/s。测量相应层面导水管截面积 ,计算相应导水管区脑脊液流量 ,并研究在一个心动周期内CSF流动改变情况。结果 :正常中脑导水管脑脊液流动在一个心动周期内表现为双向流动 ,即收缩期向下流动和舒张期向上流动 ,收缩期平均向下峰流速和舒张期平均向上峰流速分别为 12 6 7± 3 5 8mm/s和 11 5 8± 3 96mm/s,平均向下及向上流量分别为 1 311± 0 74 0ml/min(0 0 18± 0 0 12ml/心动周期 )和 1 0 6 8± 0 5 6 8ml/min(0 0 14± 0 0 0 9ml/心动周期 ) ,平均净流量为 0 2 6 0± 0 2 4 9ml/min(0 0 0 4± 0 0 0 4ml/心动周期 ) ;脑脊液向下流动平均最大峰速发生在一个心动周期的R波后平均 18%时间点 (心动周期的 5 7ms,平均心动周期 85 7ms) ,向上最大峰流速出现在心动周期的 87%时间点 (心动周期的6 86ms,平均心动周期 85 7ms) ,而逆向流动发生在R波后平均 4 4 %～ 5 8%时间点 (心动周期的 343～ 4 5 7ms,平均心动周期85 7ms)。结论 :磁共振相位对比     

EFFECTIVENESS OF CYTODIAGNOSIS WITH PANCREATIC DUCT LAVAGE FLUID FOR PANCREATIC DUCTAL CARCINOMA: NEW SAMPLING TECHNIQUE

Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular.     

Intrathecal synthesis of anti-myelin basic protein IgG in HIV-1+ patients

Human immunodeficiency virus type 1 (HIV-1)-infected individuals frequently develop a broad spectrum of neurological syndromes, classified as HIV-1-associated cognitive/motor complex. Diffuse demyelination of hemispheric white matter is a commonly observed in HIV-1 infected brain, but the events leading to myelin destruction are still obscure. Since oligodendrocyte infection by HIV-1 is not proven as yet, myelin damage in HIV-1 infection may result from indirect mechanisms such as the excessive release of myelinotoxic substances or the triggering of autoimmune responses directed to myelin constituents. To verify the latter hypothesis, we searched for elevated anti-myelin basic protein (MBP) IgG levels in the cerebrospinal fluid (CSF) and serum of 25 patients with HIV-1 infection, 12 with multiple sclerosis (MS), and 9 with non-inflammatory neurological diseases (NIND). CSF, but not serum, anti-MBP IgG levels were more frequently elevated in HIV-1⁺ (16/25, 64%) than in MS (3/12, 25%) or NIND (0/9) patients. By using the anti-MBP IgG index, the anti-MBP IgG antibody specificity index (ASI), and the search for anti-MBP oligoclonal IgG, we ascertained that anti-MBP IgG were produced within the CNS in 13 of 25 (52%) HIV-1⁺, in 6 of 12 (50%) MS, and in none of NIND patients. The incidence of increased CSF anti-MBP IgG levels was higher among HIV-1⁺ patients at stage II–III (4/4, 100%) or at stage IV B (7/9, 78%) than among those at stage IV C–IV D (5/12, 42%). Although our data indicate that intrathecal anti-MBP IgG may occur early during HIV-1 infection and that they are more common in patients with HIV-1-associated cognitive/motor complex, the possible demyelinating role of these antibodies remains to be demonstrated.