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Biomedical subjects

M Koike

Publications and source records attributed to M Koike.

At least 55 records · Page 3Linked to original sources

Loss of syndecan-1 and increased expression of heparanase in invasive esophageal carcinomas.

Heparan sulfate proteoglycans play important biological roles in cell-cell and cell-matrix adhesion, and are closely associated with growth factor actions. Loss of syndecan-1, a cell surface-bound heparan sulfate proteoglycan, has been reported for advanced head and neck carcinomas, and expression of endoglycosidic heparanase, which cleaves heparan sulfate glycosaminoglycans (HS-GAGs), is associated with invasion and metastatic potential of malignant tumors. Paraffin sections of 103 primary esophageal squamous cell carcinomas were immunohistochemically examined for the expression of syndecan-1 core protein, HS-GAGs and heparanase protein, and the results were compared with various clinicopathological parameters, such as invasion depth. For 16 cases, fresh tumor samples were quantitatively analyzed for heparanase and syndecan-1 mRNA expression by real-time RT-PCR in addition to the immunohistochemical studies. Syndecan-1 core protein and HS-GAGs expression was significantly decreased in pT2 and pT3 cases compared with their pTis and pT1 counterparts. Decreased expression of core protein and HS-GAGs was correlated with the incidence of lymphatic invasion, and venous involvement. Furthermore, decreased expression of HS-GAGs was correlated positively with the incidence of nodal metastasis and distant organ metastasis, and negatively with the grade of tumor cell differentiation. The percentage of cytoplasmic heparanase protein-positive cases increased significantly in pT2 and pT3 cases compared to that in pTis and pT1 cases, and this was associated with lymphatic invasion, and venous and lymph nodal involvement. The level of heparanase mRNA was inversely correlated with the degree of HS-GAGs expression rather than core protein. In conclusion, loss of syndecan-1 and heparanase overexpression in esophageal squamous cell carcinomas are closely associated with malignant potential. Regarding the mechanism of loss of HS-GAGs, heparanase upregulation appears to play an important role.

Adult↗

Reduced expression of laminin alpha 3 and alpha 5 chains in non-small cell lung cancers.

The basement membrane is considered to act as a barrier which hinders cancer cells from invading the surrounding stroma. In order to assess changes in essential components during neoplasia in the lung, we immunohistochemically studied distribution patterns of laminins alpha 3 and alpha 5 in 40 adenocarcinomas and 8 squamous cell carcinomas. The a 5 chain was generally preserved at the periphery, frequently disrupted in foci with alveolar collapse and absent in foci of fibroblastic proliferation within adenocarcinomas. Fragmentation and absence of laminin alpha 3 chain were more prominent than for alpha 5 chain. Laminin alpha 3 chain was partially fragmented or absent in peripheral areas of adenocarcinomas, being significantly different from alpha 5 chain. Non-small cell lung cancers with reduced alpha 5 chain showed a tendency for greater lymph node metastasis. In cultured normal air way epithelial cells, both laminin alpha 3 and alpha 5 chains were found to be expressed by northern analysis. Eleven of the twelve cultured lung cancer cell lines did not express alpha 3 chain and expression of alpha 5 chain was reduced in three. Quantitative RT-PCR analysis also demonstrated expression of laminin alpha 3 chain in adenocarcinoma tissues to be significantly lower than in normal lung tissues. These results suggest that expression of laminin alpha chains is often reduced in lung cancer cells and this might contribute to basement membrane fragmentation and subsequent proliferation of stromal elements, as well as play some role in the process of cancer cell invasion.

Adenocarcinoma↗

Expression and chromosome location of hamster Ku70 and Ku80.

Ku proteins play an important role in DNA double-strand break (DSB) repair, chromosome maintenance, and growth regulation. To understand the fundamental characteristics of Ku proteins, we examined the electrophoretic mobility and expression of hamster Ku70 and Ku80 and determined the chromosome locations of their genes. The electrophoretic mobility of hamster Ku proteins are different from that of human Ku proteins. No significant changes in the quantity of Ku proteins were observed in CHO-K1 cells treated with 10 Gy of ionizing radiation, suggesting that both proteins are expressed constitutively in amounts adequate to repair DNA DSBs. The chromosome locations of the Ku genes were determined by direct R-banding fluorescence in situ hybridization. The Ku70 gene was localized to Syrian hamster chromosome 4qa4.1--> qa4.2 and Chinese hamster chromosome 2p3.1, and the Ku80 gene was localized to Syrian hamster chromosome 4qb5--> qb6.1 and Chinese hamster chromosome 2p3.5-->p3.6. These results provide clues to the biological functions of Ku, as well as useful information for constructing comparative chromosome maps between hamsters and other mammalian species, including human, mouse, and rat.

Animals↗

Different distribution patterns of the two mannose 6-phosphate receptors in rat liver.

Two mannose 6-phosphate receptors, cation-dependent and -independent receptors (CDMPR and CIMPR), play an important role in the intracellular transport of lysosomal enzymes. To investigate functional differences between the two in vivo, their distribution was examined in the rat liver using immunohistochemical techniques. Positive signals corresponding to CIMPR were detected intensely in hepatocytes and weakly in sinusoidal Kupffer cells and interstitial cells in Glisson's capsule. In the liver acinus, hepatocytes in the perivenous region showed a more intense immunoreactivity than those in the periportal region. On the other hand, positive staining of CDMPR was detected at a high level in Kupffer cells, epithelial cells of interlobular bile ducts, and fibroblast-like cells, but the corresponding signal was rather weak in hepatocytes. In situ hybridization analysis also revealed a high level of expression of CIMPR mRNAs in hepatocytes and of CDMPR mRNA in Kupffer cells. By double immunostaining, OX6-positive antigen-presenting cells in Glisson's capsule were co-labeled with the CDMPR signal but were only faintly stained with anti-CIMPR. These different distribution patterns of the two MPRs suggest distinct functional properties of each receptor in liver tissue.

Animals↗

Synthesis and antimalarial activity of febrifugine derivatives.

The regioisomers (2a,b) of the piperidine ring of febrifugine (1a) and isofebrifugine (1b) were synthesized from 4-allyl-3-piperidone (5). Reduction of 5 afforded a mixture of the trans and cis alcohols (6a,b) without diastereoselectivity; this result differentiated it from the reduction of 2-allyl-3-piperidone (14). The antimalarial activity of 2a,b and related compounds was tested.

Antimalarials↗

Specific localization of lysosomal aminopeptidases in type II alveolar epithelial cells of the rat lung.

We previously demonstrated that lysosomal cysteine proteinases, cathepsins B, H, and L were localized in lysosomes of alveolar macrophages and bronchial epithelial cells in the rat lung, while cathepsin H, a typical aminopeptidase, was additionally distributed in lamellar bodies containing surfactant in type II alveolar epithelial cells (ISHII et al., 1991). The present immunohistochemical study further examined the localization of lysosomal aminopeptidases, cathepsin C, and tripeptidyl peptidase I (TPP-I) in the rat lung. Western blotting confirmed the presence of cathepsin C and TPP-I as active forms in the pulmonary tissue, showing 25 kD and 47 kD, respectively. Immunohisto/cytochemical observations demonstrated that positive staining for cathepsin C and TPP-I was more intensely localized in alveolar epithelial regions than in bronchial or bronchiolar epithelial cells. By double immunostaining using confocal laser microscopy, immunoreactivity for cathepsin H was found to be co-localized with that for cathepsin C or TPP-I in both type II cells and macrophages. Moreover, when doubly stained with anti-cathepsin C and ED2, single-positive type II cells could be clearly distinguished from double-positive macrophages in the alveolar region. Immunoelectron microscopy revealed the gold labeling of cathepsin C or TPP-I in multivesicular and composite bodies, and lamellar bodies of Type II cells. These results showing that lysosomal aminopeptidases such as cathepsin H, cathepsin C and TPP-I are localized in lamellar bodies of type II alveolar epithelial cells strongly argue for the participation of lysosomal aminopeptidases in the formation process of surfactant containing specific proteins.

Aminopeptidases↗

[Clinicopathologic study on chronic pancreatitis with diffuse irregular narrowing of the main pancreatic duct].

We studied the clinicopathologic features of 13 cases of chronic pancreatitis with diffuse irregular narrowing of the main pancreatic duct (MPD). It occurs frequently in relatively elder men. Diffuse irregular narrowing of the MPD and stenosis of the common bile duct on ERCP, and swelling of the pancreas on US/CT were detected in all cases. An autoimmune mechanism might be involved in the etiology at least in 5 patients with hypergammaglobulinemia and positive autoantibodies. Surgical therapy was performed in 8 patients and 3 patients were treated with steroids. No patients showed recurrence of pancreatitis. Histologic findings were characterized by diffuse lymphoplasmacytic infiltration with marked interstitial fibrosis in the pancreas, obliterated phlebitis of the pancreatic veins. Similar inflammatory process involved the bile duct and the gallbladder. These histologic findings were similar to those of multifocal fibrosclerosis. Chronic pancreatitis with diffuse irregular narrowing of the MPD is overlapped with autoimmune pancreatitis in many cases, but may be a variant of multifocal fibrosclerosis involving the pancreas in some cases.

Adult↗

Tubular osteopontin expression in patients with ANCA-associated glomerulonephritis.

OBJECTIVE: To elucidate the role of osteopontin (OPN) in monocyte recruitment in crescentic glomerulonephritis, we investigated immunohistochemical localization of OPN in the kidney and its correlation with clinical and histopathologic parameters in biopsy specimens of patients with myeloperoxidase antineutrophil cytoplasmic autoantibody- (MPO-ANCA) associated glomerulonephritis. METHODS: Twelve patients with MPO-ANCA-associated glomerulonephritis were enrolled in this study. Clinical parameters such as creatinine clearance and urinary protein excretion of each patient were obtained at the time of biopsy. Paraffin-embedded sections were used for immunohistochemical staining using the LSAB method. Five cortical interstitial fields randomly selected at original magnification x 200 were assessed using a computer-assisted color image analyzer. Tubular OPN expression was assessed as the percentage of positive area in the tubulointerstitium. Double immunofluorescent staining using antibodies against OPN and alpha(v)beta3 was performed. RESULTS: In all of the cases studied, OPN was occasionally localized within the glomeruli, and expressed slightly in proximal tubular epithelium and significantly in distal tubular epithelium. Tubular OPN expression tended to be promoted in the interstitium infiltrating by numerous monocytes/macrophages. The extent of tubular OPN expression was positively correlated with serum ANCA titers and urinary OPN concentrations. Enhanced alpha(v)beta3 expression appeared in the distal tubular epithelium expressing OPN. CONCLUSION: These results suggest that inducible expression of OPN and alpha(v)beta3 in the tubular epithelium seems to be associated with interstitial moncyte infiltration and subsequent tubulointerstitial changes in human MPO-ANCA-associated glomerulonephritis.

Adult↗

Laparoscopic diagnosis and clinical course of chronic schistosomiasis japonica.

Laparoscopic findings of nine patients with chronic schistosomiasis japonica were analyzed and compared to hepatic ultrasonograms, computed tomography (CT) scans and histological findings from the same patients. In all nine patients laparoscopy revealed yellowish, small speckles, approximately 50 microm in diameter, sparse or clustered over the liver surface, which were later found to represent subcapsular calcified ova of Schistosoma japonicum. While the liver surface was almost smooth in mild schistosomiasis, multiple whitish markings and irregular, relatively wide, groove-like septums were seen in more advanced cases. In severe schistosomiasis block-like formations of variable size, separated by groove-like depressions, made the liver surface appear like a tortoise shell. In moderate or severe schistosomiasis ultrasonography revealed spotted high echoes and CT scans demonstrated network patterns and lineal calcified spots. The liver surface of chronic schistosomiasis japonica without re-infection appeared stable without change over time but with a tendency to improve. Hepatocellular carcinoma was initially recorded in two of the nine patients and follow-up revealed a further two with the same diagnosis. However, all these four cases also had chronic hepatitis C (HCV). Hepatocellular carcinoma was not detected in patients without viral hepatitis, indicating that hepatic viral infection is more important than schistosomiasis in promoting the development of hepatocellular carcinoma.

Aged↗

Human tumor necrosis factor-alpha mutant RGD-V29 (F4614) shows potent antitumor activity and reduced toxicity against human tumor xenografted nude mice.

The antitumor effects of human tumor necrosis factor-alpha (TNF) mutant RGD-V29 (code no. F4614), that includes the cell adhesive sequence (4)Arg-(5)Gly-(6)Asp and (29)Arg-->Val substitution, were evaluated. The therapeutic index, a measure of the extent of the therapeutically-effective range, using three constitutive administrations of RGD-V29 in Meth A-bearing mice was 4.8, whereas that of recombinant human TNF (rhTNF) ((1)SSS(4)RTPSDK...(29)RR...(155)L) was 2.8, clearly indicating that the effective RGD-V29 dose-range was extended. Furthermore, RGD-V29 showed potent antitumor activity against human lung cancer Mqnu-1 xenografted nude mice without severe gastrointestinal and other organ toxicities, even when administered at the maximal tolerated dose (MTD). In contrast, rhTNF induced severe toxicity at the MTD. Direct cytotoxicity of RGD-V29 against Mqnu-1 cells was similar to that of rhTNF. In addition, a cytotoxicity assay using a tumor-derived endothelial-like cell (tEC)/normal endothelial cell (nEC) system used to study TNF antitumor effects on tumor-associated endothelial cells, suggested that RGD-V29 showed preferential cytotoxicity toward tumor-associated endothelial cells compared with rhTNF. Thus, RGD-V29 appears to be a low-toxicity mutant of rhTNF that shows preferential activity towards tumors, and therefore merits further investigation in pre-clinical and clinical studies.

Amino Acid Sequence↗

Ku70 can translocate to the nucleus independent of Ku80 translocation and DNA-PK autophosphorylation.

Ku plays an important role in multiple nuclear processes, e.g., DNA repair, chromosome maintenance, and transcriptional regulation. Although some evidence suggests that the nuclear translocation of Ku plays a key role in regulating the function of Ku, the mechanism is poorly understood. Using the site-directed mutagenesis technique, we demonstrate here that Ku70 can translocate to the nucleus without heterodimerization with Ku80. The nuclear accumulation of Ku70 mutants of the nuclear localization signal, which retained their binding ability with Ku80, was diminished. On the other hand, Ku70 mutants which lacked the ability to bind with Ku80 could translocate to the nuclei. Human Ku70, when transfected, accumulated within the nuclei of hamster xrs-6 cells which had undetectable DNA-PK activity and Ku80. Ku70 and Ku80 mutants of DNA-PK phosphorylation sites showed normal heterodimerization and nuclear translocation. These findings also support the idea that Ku70 can translocate to the nucleus independent of DNA-PK autophosphorylation.

Active Transport, Cell Nucleus↗

Cathepsin D deficiency induces lysosomal storage with ceroid lipofuscin in mouse CNS neurons.

Cathepsin D-deficient (CD-/-) mice have been shown to manifest seizures and become blind near the terminal stage [approximately postnatal day (P) 26]. We therefore examined the morphological, immunocytochemical, and biochemical features of CNS tissues of these mice. By electron microscopy, autophagosome/autolysosome-like bodies containing part of the cytoplasm, granular osmiophilic deposits, and fingerprint profiles were demonstrated in the neuronal perikarya of CD-/- mouse brains after P20. Autophagosomes and granular osmiophilic deposits were detected in neurons at P0 but were few in number, whereas they increased in the neuronal perikarya within days after birth. Some large-sized neurons having autophagosome/autolysosome-like bodies in the perikarya appeared in the CNS tissues, especially in the thalamic region and the cerebral cortex, at P17. These lysosomal bodies occupied the perikarya of almost all neurons in CD-/- mouse brains obtained from P23 until the terminal stage. Because these neurons exhibited autofluorescence, it was considered that ceroid lipofuscin may accumulate in lysosomal structures of CD-/- neurons. Subunit c of mitochondrial ATP synthase was found to accumulate in the lysosomes of neurons, although the activity of tripeptidyl peptidase-I significantly increased in the brain. Moreover, neurons near the terminal stage were often shrunken and possessed irregular nuclei through which small dense chromatin masses were scattered. These results suggest that the CNS neurons in CD-/- mice show a new form of lysosomal accumulation disease with a phenotype resembling neuronal ceroid lipofuscinosis.

Action Potentials↗

The adoption of a twisted structure of importin-beta is essential for the protein-protein interaction required for nuclear transport.

Importin-beta is a nuclear transport factor which mediates the nuclear import of various nuclear proteins. The N-terminal 1-449 residue fragment of mouse importin-beta (impbeta449) possesses the ability to bidirectionally translocate through the nuclear pore complex (NPC), and to bind RanGTP. The structure of the uncomplexed form of impbeta449 has been solved at a 2.6 A resolution by X-ray crystallography. It consists of ten copies of the tandemly arrayed HEAT repeat and exhibits conformational flexibility which is involved in protein-protein interaction for nuclear transport. The overall conformation of the HEAT repeats shows that a twisted motion produces a significantly varied superhelical architecture from the previously reported structure of RanGTP-bound importin-beta. These conformational changes appear to be the sum of small conformational changes throughout the polypeptide. Such a flexibility, which resides in the stacked HEAT repeats, is essential for interaction with RanGTP or with NPCs. Furthermore, it was found that impbeta449 has a structural similarity with another nuclear migrating protein, namely beta-catenin, which is composed of another type of helix-repeated structure of ARM repeat. Interestingly, the essential regions for NPC translocation for both importin-beta and beta-catenin are spatially well overlapped with one another. This strongly indicates the importance of helix stacking of the HEAT or ARM repeats for NPC-passage.

Amino Acid Sequence↗

A psychosocial group intervention for Japanese women with primary breast carcinoma.

BACKGROUND: To the authors' knowledge, there had been no evidence for the efficacy of psychosocial intervention among Japanese cancer patients. The objective of this study was to determine the effect of a psychosocial group intervention in reducing psychologic distress and enhancing coping in this population in a randomized controlled trial. METHODS: The patient selection criteria were age younger than 65 years, lymph node metastasis positive and/or histologic or nuclear Grade 2-3, and surgery undergone within the previous 4-18 months as of the start of the study. We conducted a 6-week, structured, psychosocial group intervention. The intervention consisted of health education, coping skills training, stress management, and psychologic support. Subjects were assessed for psychologic distress and coping by administering the Profile of Mood States (POMS), Mental Adjustment to Cancer (MAC) scale, and Hospital Anxiety and Depression (HADS) scale at the baseline, at 6 weeks, and at 6 months. RESULTS: Fifty (33%) of the 151 patients participated and were randomized, and 46 (30%) completed the study. The experimental group had significantly lower scores than the controls for total mood disturbance and significantly higher scores for vigor on the POMS, and significantly higher scores for fighting spirit on the MAC at the end of the 6-week intervention. These improvements were sustained over 6 months of follow-up. CONCLUSIONS: The results of this study suggest that a short term psychosocial group intervention produces significant long term improvement in the quality of life of Japanese patients with primary breast carcinoma.

Adaptation, Psychological↗

Distinction of differentiated type early gastric carcinoma with gastric type mucin expression.

BACKGROUND: Intestinal and diffuse gastric carcinomas differ in morphology and growth behavior. Differentiated type gastric carcinoma (DGC), which corresponds roughly with the intestinal type of Lauren, can demonstrate phenotypic properties associated with mucin expression and brush border. However, their clinical significance is controversial. A classification based on mucin phenotype and brush border was performed to determine the clinicopathologic diversity of DGCs in their early stage. METHODS: A total of 120 specimens from 116 DGC patients with definite submucosal invasion were evaluated both macroscopically and histologically. All sections were examined immunohistochemically with human gastric mucin, Muc-2, and CD10 and with mucin histochemically with paradoxical concanavalin A staining and high iron Diamine-Alcian Blue. They were classified into gastric type (G-type), intestinal type (I-type), mixed gastric and intestinal type (M-type), or null type (N-type) phenotypes. The immunoreactivity of E-cadherin and beta-catenin also was investigated to determine the correlation between mucin phenotype and clinicopathologic factors. RESULTS: The G-type phenotype was found to be in contrast to I-type: G-type was an independent factor associated with lymph node metastasis. Significant correlations were observed between the G-type phenotype and the complex type carcinoma found that was histologically: lymphatic invasion, lymph node metastasis, and the abnormal expression of E-cadherin. A significant difference in the proportion of mucin phenotypes between papillary type and tubular type carcinoma was observed. G-type was found to be the predominant phenotype in papillary carcinoma in contrast to tubular carcinoma. CONCLUSIONS: The G-type mucin phenotype and papillary adenocarcinoma should be distinguished from other types of DGCs because of their increased malignant potential in the incipient phase of invasion and metastasis. The significance of G-type and papillary adenocarcinoma should be reflected in the treatment of patients with early stage DGCs, including endoscopic mucosal resection.

Adenocarcinoma↗

Affinity chromatography for purification of two urokinases from human urine.

A new affinity chromatography (hydrophobic-mediated affinity chromatography), which was characterized by the matrix having both affinity site to urokinase and hydrophobic site, was established for the purification of urokinase from human urine. The hydrophobic affinity matrix (tentatively named PAS in the text) was prepared by immobilizing 6-aminocaproic acid on Sepharose CL-6B, followed by a coupling p-aminobenzamidine to a part of the hydrophobic site on the matrix. The PAS matrix was applied to the purification of urokinase from human urine, and high- and low-molecular weight pure urokinases were efficiently obtained in high yield by the present method.

Chromatography, Affinity↗

[Laparoscopic radical nephrectomy for renal cell carcinomas; report on two initial cases].

We recently performed a laparoscopic radical nephrectomy (LRN) on two patients with a renal cell carcinoma. Case 1, a 72-year-old man, was diagnosed as having a renal cell carcinoma 2.5 cm in diameter in the right kidney, and also a submucosal tumor of the cecum. LRN and laparoscopically assisted ileocecal resection were performed using a transperitoneal approach on September 28, 1999. Total operation time and blood loss during the operation were 308 minutes and 320 ml, respectively. The operation time needed for LRN, which was calculated as the total operation time minus the time spent on ileocecal resection, was 199 minutes. There were no complications after surgery, and the patient was recommended for discharge on the 7th postoperative day, but was actually discharged on the 10th postoperative day. Case 2, an 81-year-old man, was diagnosed as having a renal cell carcinoma 3.0 cm in diameter in the right kidney. He had been undergone a total gastrectomy for a gastric carcinoma at age 77, and a sigmoidectomy for a sigmoid colon carcinoma at age 79. A transperitoneal approach was applied for LRN to detect any recurrence of previous carcinomas on September 30, 1999. During adhesiolytic procedures, the colon was injured due to an inappropriate maneuver of the grasping forceps. A small laparotomy (5 cm) was required for repair of the colon. The total operation time and blood loss during surgery were 370 minutes and 850 ml. The operation time calculated from the video of LRN was 274 minutes. Two additional surgical procedures were required in this case. The first was for a postoperative intraperitoneal hemorrhage due to the hemoclip dropping out of the small vein. The second was for hemorrhage in the abdominal wall. Fortunately, the clinical course after surgery was good and the patient was discharged on the 8th postoperative day. There were no complications in case 1. Omitting ileocecal resection was considered to speed up oral intake, leading to earlier discharge. However, major complications occurred in case 2. It is important to clarify the cause of postoperative hemorrhage by careful observation of the video recording, in order to suggest safer procedures in laparoscopic surgery. Although these are only two LRN experiences, we are convinced that LRN can improve postoperative QOL (Quality of life) and is an acceptable alternative for the treatment of renal cell carcinomas.

Aged↗