脑内和肌内接种小鼠胶质母细胞瘤株后神经末梢的观察

本实验应用Nonidez及Glees二种镀银法,对诱发的小鼠胶质母细胞瘤株(G 422)进行了观察。脑内及肌内接种胶质母细胞瘤后,在肿瘤边缘可见大小不等的神经束,伴随或不伴随血管伸入瘤内。有的在血管周围间隙形成血管周围神经丛。这些神经纤维与肿瘤周围宿主的脑组织、皮下、毛囊和肌肉间隙的神经纤维相联系。因此我们推测肿瘤内的神经是由肿瘤周围宿主的器官组织的神经延伸来的。肿瘤边缘的神经纤维的数量多于核心区,走行于肿瘤的间质或实质,沿途不断分支,终末分布到肿瘤细胞的表面。我们观察到球形、游离分叉状、梭形、环形、树枝状、杵状及丛刷状等类型的神经末梢。以上观察表明,恶性肿瘤——小鼠胶质母细胞瘤是受神经支配的。     

中药蜈蚣对小鼠胚胎发育的影响

孕鼠１６１只随机分组，在孕期第７－１１天给实验组分别以５００ｍｇ／（ｋｇ．ｄ）（蜈蚣１组）及１０００ｍｇ／（ｋｇ．ｄ）（蜈蚣２组）的中药蜈蚣煎剂灌胃，至孕期１８天记录各组孕鼠和胎鼠的发育情况。结果表明：蜈蚣１，２两组致畸作用明显，死胎，吸收胎比例升高；蜈蚣２组胎鼠和孕鼠的体重均下降，堕胎作用显著，与对照组比较，差异均有非常显著意义（Ｐ＜０．０１）。     

Altered GABAB receptor immunoreactivity in the gerbil hippocampus induced by baclofen and phaclofen, not seizure activity

The present study was performed to determine whether the effects induced by GABA(B) receptor-acting drugs would be related with the alteration in GABA(B) receptor expression in the hippocampus using Mongolian gerbil, a genetic epilepsy model. The distribution patterns of both GABA(B) receptor 1A/B and GABA(B)receptor 2 immunoreactivities were similarly detected in the hippocampi of normal and seizure-prone gerbils. Following baclofen (GABA(B) receptor agonist) or phaclofen (GABA(B) receptor antagonist) treatment, GABA(B) receptor immunoreactivities were decreased or increased by dose-dependent manners, respectively. Vigabatrin (GABA transaminase inhibitor) or 3-mercaptopropionic acid (GAD inhibitor) treatment did not affect GABA(B) receptor expressions. These findings suggest that GABA(B) receptor expression in the gerbil hippocampus may be altered by baclofen or phaclofen treatment.     

SIGN-R1, a novel C-type lectin expressed by marginal zone macrophages in spleen,mediates uptake of the polysaccharide dextran

The marginal zone macrophages of the spleen are implicated in the clearance of polysaccharides, but underlying mechanisms need to be pinpointed. SIGN-R1 is one of five recently identified mouse genes that are homologous to human DC-SIGN and encode a single, external, C-terminal C-type lectin domain. We find that a polyclonal antibody to a specific SIGN-R1 peptide reacts primarily and strongly with a subset of macrophages in the marginal zone of spleen and lymph node medulla. In both sites, SIGN-R1 exists primarily in an aggregated form, resistant to dissociation into monomers upon boiling in SDS under reducing conditions. Upon transfection into three different cell lines, high-mol.-wt forms bearing SIGN-R1 are expressed, as well as reactivity with ER-TR9, a mAb previously described to react selectively with marginal zone macrophages. SIGN-R1-expressing macrophages preferentially sequester dextrans following i.v. injection. Likewise, when phagocytic cells are enriched from spleen and tested in culture, dextran is selectively endocytosed by a subset of very large SIGN-R1(+) cells representing approximately 5% of total released macrophages. Uptake of FITC-dextran by these macrophages in vivo and in vitro is blocked by ER-TR9 and polyclonal anti-SIGN-R1 antibodies. Following transfection with SIGN-R1, cell lines become competent to endocytose dextrans. The dextran localizes primarily to compartments lacking transferrin receptor and the LAMP-1 CD107a panlysosomal antigen. Therefore, SIGN-R1 mediates the uptake of dextran polysaccharides, and it is predominantly expressed in the macrophages of the splenic marginal zone and lymph node medulla.     

Early rehabilitation program in postmastectomy patients: a prospective clinical trial

The purpose of this study was to determine whether 20 patients who received an early postmastectomy rehabilitation treatment program showed more improvement in range of shoulder motion and functional activities than 13 patients who received instruction for exercise only. Data were obtained at preoperatively, three days after operation, at discharge and at postdischarge one month for each patient on parameters such as range of motion of the ipsilateral shoulder joint, upper extremity circumferential measurements, as well as 10 elements of shoulder function. Postoperatively, both groups showed an increased range of motion of the shoulder joint and improved functional activities, but the group that received postoperative rehabilitation management had a better range of shoulder motion and less difficulty in five items for functional assessment. This study also showed that an early rehabilitation program did not increase postoperative complications. We concluded that an early rehabilitation program or intensive instruction program only by a well-trained physical therapist or physiatrist was beneficial to postmastectomy patients in regaining the function and range of shoulder motion, and significantly better in a rehabilitation group.     

Villous adenoma of the bile ducts: a case report and a review of the reported cases in Korea

Villous adenomas are benign epithelial lesions with malignant potential which can occur at any site in the gastrointestinal tract. They are usually encountered in the rectum and colon, less frequently in the small bowel and very rarely in the biliary trees. Nine cases of bile duct villous adenomas have been reported in the literature. However, 4 cases of bile duct villous adenomas have been reported in the Korean literature. Recently, we experienced a case of villous adenoma in the common hepatic duct in a 77-year-old man presenting with obstructive jaundice in which preoperative histologic diagnosis of villous adenoma played a critical role in managing this patient. Herein, we present a case report of bile duct villous adenoma and a review of the reported cases in Korea to help define and manage this rare disease entity in the bile ducts. In addition, confusing nomenclature of bile duct adenomas is discussed.     

Immunoelectron microscopic identification of human NK cells by FITC-conjugated anti-Leu-11a and biotinylated anti-Leu-7 antibodies

Human natural killer (NK) cells have been reported to express various surface antigens. The majority and the most functionally potent NK cells are Leu-11a (NKP-15) positive cells. Only a small number of functional NK cells express Leu-7 (HNK-1) antigen. In the present study, we have established techniques for immunoelectron microscopic identification of NK cells by mouse monoclonal FITC-conjugated anti-Leu-11a and biotinylated anti-Leu-7 antibodies. Ficoll-Hypaque-isolated peripheral blood lymphocytes (PBL) were reacted with the specific antibodies before or after fixation in a 1% glutaraldehyde/1% paraformaldehyde fixative. Prefixation labeling of viable cells with the antibodies was carried out at 4 degrees C or 37 degrees C. Cells prelabeled with anti-Leu-11a antibody were reacted with secondary antibodies either before or after fixation. Anti-Leu-7 antibody was stained directly via an avidin-biotin-peroxidase (ABC) system, anti-Leu-11a antibody was stained indirectly by the ABC immunoperoxidase procedure via a biotinylated anti-mouse IgG secondary antibody or by a 10 nm or 40 nm colloidal gold-labeled anti-mouse IgG antibody. Results indicate that Leu-7 antigen could be localized by incubation with the specific antibody either before or after 20 min fixation; however, Leu-11a antigen was totally abrogated following the same fixation procedure. The Leu-11a antigen was well stained by the methods of prefixation labeling of cells with anti-Leu-11a antibody and incubation with a biotinylated secondary antibody and the ABC system after fixation. With respect to colloidal gold labeling, better results were obtained when cells were reacted with the gold-labeled antibodies immediately after incubation with anti-Leu-11a antibody but before fixation. Ultrastructurally both Leu-7 positive (+) and Leu-11a positive (+) cells shared common ultrastructural features associated with large granular lymphocytes. Using the above described techniques, we found approximately 2-5% Leu-7+ and 9-15% Leu-11a+ cells in the PBL of healthy donors. The overall results suggest that Leu-11a antigen is more sensitive to glutaraldehyde/paraformaldehyde fixation than Leu-7, since it can be localized only by prefixation labeling procedures; the ABC immunoperoxidase procedure is an ideal technique for labeling NK cells for light and electron microscopic enumeration; the immunogold method provides an adequate technique for labeling NK cells which are designated for ultracytochemical studies.     

Frequency-to-voltage conversion in the pyramidal tract neuron: an important role of the inhibitory postsynaptic potential

Frequency-coded impulses are known to be converted into postsynaptic potentials (PSPs) at the synapse of a target neuron. This can be termed frequency-voltage (F-V) conversion. Studies on this problem in pyramidal tract neurons (PTNs) showed that not only the amplitude but also the duration of depolarizing PSPs was determined as a function of the input impulse frequency. Two opposite patterns of F-V conversion were observed following activation of two input systems to PTNs. Inhibitory postsynaptic potentials were found to play an important role in the regulation of the duration of PSPs by curtailing excitatory post-synaptic potentials.