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1.
To elucidate the role of the spiral limbus in glucose transport in the cochlea, we analyzed the expression and localization of GLUT1, connexin26, connexin30, and occludin in the spiral limbus of the rat cochlea. GLUT1 and occludin were detected in blood vessels. GLUT1, connexin26, connexin30, and occludin were also expressed in fibrocytes just basal to the supralimbal lining cells. Connexin26 and connexin30 were present among not only these GLUT1-positive fibrocytes but also GLUT1-negative fibrocytes. In vivo glucose imaging using 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (6-NBDG, MW 342) together with Evans Blue Albumin (EBA, MW 68,000) showed that 6-NBDG was rapidly distributed throughout the spiral limbus, whereas EBA was localized only in the vessels. Moreover, the gap junctional uncoupler heptanol inhibited the distribution of 6-NBDG. These findings suggest that gap junctions play an important role in glucose transport in the spiral limbus, i.e., that gap junctions mediate glucose transport from GLUT1-positive fibrocytes to GLUT1-negative fibrocytes in the spiral limbus.  相似文献   
2.
The present study shows that Langerhans cells can be differentiated from Interdigitating cells at the light microscopic level. Superficial lymph nodes and skin taken from necropsies and the lymph nodes of dermatopathic lymphadenopathy (DPL) were used for this experiment. Sections of lymph node and skin were embedded using the acetone, methyl benzoate and xylene (AMeX) method and dendritic cells were immunostained with anti S-100 protein antibody (S-100, and OKT-6 (CD1a) using the restaining method. Langerhans cells in the skin were positive for both CD1a and S-100. Dendritic cells positive for both CD1a and S-100, and dendritic cells positive for S-100, but not for CD1a were observed in superficial lymph nodes. In normal superficial lymph nodes, there were more interdigitating cells than Langerhans cells. The majority of the dendritic cells in the DPL were Langerhans cells. We conclude that the S-100 and CD1a positive cells are Langerhans cells, and the S-100 positive-CD1a negative cells are interdigitating cells.  相似文献   
3.
Correction of congenital microtia using the tissue expander   总被引:6,自引:0,他引:6  
Y Hata  K Hosokawa  K Yano  K Matsuka  O Ito 《Plastic and reconstructive surgery》1989,84(5):741-51; discussion 752-3
We attempted auricular reconstruction using Radovan-type inflatable silicone expanders in six children and one adult, with the complete hypoplastic, the conchal remnant, and constricted type of microtia. Ear frameworks, including the helix, anthelix, concha, and tragus, were prepared using autologous rib cartilage. Based on the surface area of the normal adult auricle, the silicone expander was tentatively shaped and sized into a rotated semiellipse and expanded with 70 cc saline. Auricular reconstruction on the framework was completed at the time of insertion in four of the seven patients, requiring no elevation of the ear. The reconstructed auricle was satisfactory in both color and texture and had nearly normal sensation. Mild complications were noted in three of the seven patients. However, no resorption of the inserted rib cartilage has been observed 14 months to 2 years and 5 months after the operation. Slight shrinkage of the expanded skin was noted in each patient.  相似文献   
4.
Shape variations in the dentition and the cranium were analyzed for sevenSaguinus forms of the hairy-face tamarin by applying the factor analysis method. The results obtained for the dental and cranial measurements were almost consistent with each other. The magnitude of the difference in shape factors between theS. nigricollis group and theS. midas group is appreciably larger than that between the former group and theS. mystax group. If the ancestral geographic centre of origin is postulated as being within the region which is inhabited by the livingS. nigricollis group, the morphological distances between any pairs of groups correlate well with the geographic distances between them. Concerning the dental and cranial morphologies, the physical changes in the three species group probably took place in two directions; that is, from theS. nigricollis group to theS. mystax group, and from theS. nigricollis group to theS. midas group. The forms belonging to each species group are more closely related to each other, with the exception ofS. imperator in theS. mystax group. The uniqueness ofS. imperator was clearly demonstrated by factor analysis and distance analysis. In theS. mystax group, although still hypothetical,S. imperator may have been related only through the basic ancestral stock toS. labiatus andS. mystax.  相似文献   
5.
Comparison of growth properties of carrot hairy root in various bioreactors   总被引:1,自引:0,他引:1  
Summary Growth properties of carrot hairy root cells in various bioreactors were investigated. A turbine-blade reactor and an immobilized rotating drum reactor were found to be advantageous for the hairy root culture because of a high oxygen transfer coefficient (k in L a). After 30 days of culture, 10 g/l of dry hairy root cells were obtained in both bioreactors and maximum growth rates (V m ) were found to be 0.63 and 0.61 g/l per day for the turbine-blade reactor and immobilized rotating drum reactor, respectively. Specific growth rates () at various cultivation times were observed to be linearly proportional to X/k l a for both bioreactor configurations where X is the cell concentration. The estimated specific oxygen uptake rate of 0.34 mmol O2/g dry cells per hour compares fairly well with an experimental value of 0.3.  相似文献   
6.
Summary Rat fibrosarcoma cells infected with Friend leukemia virus (FV-KMT-17) grow for a short time and then regress spontaneously in syngeneic hosts. This regression mechanism was examined by analyzing the immunomodulating action of the antitumor drugs busulfan (BU) and cyclophosphamide (CY). In preliminary experiments, the optimum dosages of BU and CY for the enhancement of DTH responses to SRBC were 10 mg/kg and 40 mg/kg respectively. Treatment of rats with BU (10 mg/kg) on day 5 induced the regression of KMT-17 cells, while in contrast, the same drug delayed the spontaneous regression of FV-KMT-17 cells. Pretreatment with CY (40 mg/kg) on day 5 did not affect the growth of KMT-17 or FV-KMT-17 cells. After the same treatment schedule, BU inhibited humoral antibody formation against SRBC and against virus-associated antigen (VAA), NK cell activity, and ADCC effector cell activity. On the other hand, CY did not affect the activities of NK cells or ADCC effector cells, although it significantly augmented the DTH responses to SRBC and the production of antibody to VAA but had no effect on production of antibodies to SRBC. These results suggest that NK cells and ADCC may play an important role in the initial stage of the spontaneous regression of FV-KMT-17 cells.Supported in part by a Grant-in-Aid for Cancer Research from the Japanese Ministry of Education Abbreviations used: BU, busulfan; CY, cyclophosphamide; PFC assay, plaque forming cell assay; VAA, virus-associated antigen; NK cell, natural killer cell; ADCC, antibody dependent cellular cytotoxicity; MuLV, murine leukemia virus; DTH, delayed type hypersensitivity; SRBC, sheep red blood cells; C.I., cytotoxic index; CRBC, chicken red blood cells; IL-1, interleukin 1; IL-2, interleukin 2; IFN, interferon  相似文献   
7.
The dental and cranial morphologies of all species ofSaguinus, S. oedipus, S. geoffroyi, S. leucopus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas are examined. The following hypotheses are developed by cladistic methodology, using only synapomorphic characters to assess the interspecific relationships ofSaguinus.Saguinus are divided into two main groups; one consists ofS. oedipus, S. geoffroyi, andS. leucopus, and the other includesS. inustus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas. In the former group,S. oedipus is more closely related toS. geoffroyi than either is toS. leucopus. In the latter group,S. labiatus, S. mystax, andS. imperator are classified into one group, andS. bicolor andS. midas form one monophyletic group.  相似文献   
8.
Two putative serum precursors which cross-react with antiserum against murine senile amyloid protein (ASSAM) were isolated from the high density lipoprotein (HDL) of normal mouse serum. Apolipoproteins designated "apoSASSAM-1" and "apoSASSAM-2" have the same molecular weight as tissue amyloid fibril protein. ApoSASSAM-1 and apoSASSAM-2 migrate to an intermediate position between apoA-I and apoC on alkaline-urea polyacrylamide gel electrophoresis and are present mainly in HDL apoproteins and to a slight extent in very low density lipoprotein apoproteins when compared to apoC. ApoSASSAM-1 and apoSASSAM-2 are polymorphic; there are two apparent isoproteins of apoSASSAM-1 with isoelectric points of 4.72 and 4.79 and two major isoproteins of apo-SASSAM-2. Subunit bands of ASSAM separated by alkaline-urea polyacrylamide gel electrophoresis and that migrated to the same positions as apoSASSAM-1 and apoSASSAM-2 were labeled by anti-apoSASSAM-1 antiserum. The amino acid compositions of apoSASSAM-1 and apoSASSAM-2 were much the same and closely resembled those of ASSAM and mouse apoA-II. Sequence analysis of apoSASSAM and ASSAM revealed a blocked amino terminus. ApoSASSAM is considered to be a mouse apoA-II and probably transforms to amyloid fibril "ASSAM" in tissues through a process yet to be clarified.  相似文献   
9.
10.
Summary We observed that after KMT-17 cells had been treated with bleomycin (BLM), even with a dose as high as 160 g/ml, they were still able to form colonies in soft agar. We then studied the susceptibility of KMT-17 cells treated with BLM to activated macrophages. During a colony inhibition assay, BLM-treated KMT-17 cells were found to be much more susceptile to activated macrophages than nontreated KMT-17 cells, moreover, a tumor neutralizing assay showed that the growth of BLM-treated KMT-17 cells was also significantly inhibited by activated macrophages as compared with nontreated KMT-17 cells. Macrophages activated by both BLM and the Nocardia rubra cell wall skeleton were able to mediate such tumor inhibition activity in BLM-treated KMT-17 cells. Activated macrophages did not seem to have strong antitumor activity against nontreated KMT-17 cells in vivo, however, the life span of the rats which were inoculated i. p. with KMT-17 cells was significantly expanded after the tumorbearing rats were given BLM i.p. The data presented here suggest that not only does BLM have a direct tumoricidal effect on KMT-17 cells, it also regulates immunosensitivity of targets to immune effectors. We also discuss the mechanism for enhancing the susceptibility of KMT-17 cells to activated macrophages brought about by treatment with BLM.Supported in part by a Grant-in-Aid for Cancer Research from the Japanese Ministry of Education, Science, and Culture  相似文献   
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