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K Suda

Publications and source records attributed to K Suda.

At least 37 records · Page 2Linked to original sources

Histopathological study on mechanism and background of tumor-forming pancreatitis.

Fifteen cases of tumor-forming pancreatitis, detected as tumors by diagnostic imaging or by physical examination were histologically examined. Eleven of the 15 patients were heavy drinkers. Tumorous lesions were located in the head of the pancreas in 11 cases and in the body or tail of the pancreas in four cases. Macroscopic examination revealed tumorous swelling or sclerotic appearance in the pancreatic tissue. Histologically, these lesions showed tumorous swelling with (n = 12) or without (n = 3) a background of chronic pancreatitis. In the former, the tumorous lesions consisted of extensive fibrosis, including necrosis or abscesses, stones and reparative granulation tissue, and there was a successive transition to the surrounding chronic pancreatitis pattern. The latter three tumorous lesions presented with inter- and intralobular fibrosis with lymphoid hyperplasia or lymphoplasmacytic infiltration and were adjacent to normal pancreatic tissue. Therefore, tumor-forming pancreatitis shows at least two distinct types: a reparative tumorous swelling with a background of chronic pancreatitis, which is considered to have given rise to the tumor at some stage; and a lymphoid and fibrous proliferation in normal pancreatic tissue, which is considered to represent an autoimmune-related disease process.

Adult↗

Pancreaticobiliary maljunction: etiologic concepts based on radiologic aspects.

BACKGROUND: The purpose of this study was to develop a new concept of the embryonic etiology of pancreaticobiliary maljunction (PBM) based on cholangiopancreatograms. METHODS: The subjects were 202 patients with PBM (60 men and 142 women) in whom the junction of the pancreatic and bile ducts was radiologically diagnosed as being located outside of the duodenal wall; 133 of the 202 patients also had congenital cystic dilatation of the bile duct (CCBD). RESULTS: The length of the duct from the junction to the orifice of the major papilla (the common channel) ranged from 0.5 to 5 cm on the cholangiopancreatograms. Small radicles of the pancreatic duct arose from the common channel in 36 of the 202 patients. This finding suggests that the common channel is itself the main pancreatic duct in patients with PBM. Moreover, cholangiopancreatography revealed that in 99 of the 202 patients, there was a narrowed duct segment distal to the biliary cyst in patients with CCBD or distal to the normal bile duct in those without CCBD; the length of the narrowed segment varied. Histologic examination revealed smaller branches that had arisen from this narrowed segment in 2 anatomic specimens. This also suggests that the narrowed ductal segment belongs to the pancreatic duct system. CONCLUSION: PBM is an anomaly that is probably caused by a disturbance in the embryologic connections (misarrangement) of the pancreatic and biliary duct system that occurs extremely early during gestation when the bile duct joins with the ventral pancreatic duct system. PBM is not due to an arrest of the normal migration of the common channel into the duodenal lumen during embryonic development.

Adult↗

Bacterial Na(+)-ATP synthase has an undecameric rotor.

Synthesis of adenosine triphosphate (ATP) by the F(1)F(0) ATP synthase involves a membrane-embedded rotary engine, the F(0) domain, which drives the extra-membranous catalytic F(1) domain. The F(0) domain consists of subunits a(1)b(2) and a cylindrical rotor assembled from 9-14 alpha-helical hairpin-shaped c-subunits. According to structural analyses, rotors contain 10 c-subunits in yeast and 14 in chloroplast ATP synthases. We determined the rotor stoichiometry of Ilyobacter tartaricus ATP synthase by atomic force microscopy and cryo-electron microscopy, and show the cylindrical sodium-driven rotor to comprise 11 c-subunits.

Bacteria, Anaerobic↗

Effect of positive and negative emotion on stimulus-preceding negativity prior to feedback stimuli.

Stimulus-preceding negativity (SPN) was recorded to investigate the effect of positive and negative emotion on the SPN preceding feedback stimuli. In the time-estimation task in which an acoustic stimulus was presented 3 s after a voluntary movement, (1) the negative valence (aversive band noise and pure tone) and (2) the positive valence (reward and no-reward) of feedback stimuli were manipulated. During noise conditions, participants received the band noise as a feedback stimulus except when their time estimations were accurate. They received a monetary reward for accurate time estimations under the reward conditions. The prefeedback SPN was larger under reward than no-reward conditions. In addition, the prefeedback SPN in the noise condition was larger compared with the pure tone condition. Our results appear to suggest that emotional anticipation is important in eliciting the prefeedback SPN.

Acoustic Stimulation↗

Phenotypic characterization of human umbilical vein endothelial (ECV304) and urinary carcinoma (T24) cells: endothelial versus epithelial features.

ECV304 cells reported as originating from human umbilical vein endothelial cells by spontaneous transformation have been used as a model cell line for endothelia over the last decade. Recently, deoxyribonucleic acid fingerprinting revealed an identical genotype for ECV304 and T24 cells (urinary bladder carcinoma cell line). In order to resolve the apparent discrepancy between the identical genotype and the fact that ECV304 cells phenotypically show important endothelial characteristics, a comparative study was performed. Immortalized porcine brain microvascular endothelial cells/C1-2, and Madin Darby canine kidney cells were included as typical endothelial and epithelial cells, respectively. Various methods, such as confocal laser scanning microscopy. Western blot, and protein activity tests, were used to study the cell lines. ECV304 and T24 cells differ in criteria, such as growth behavior, cytoarchitecture, tight junction arrangement. transmembrane electrical resistance, and activity of gamma-glutamyltransferase. Several endothelial markers (von Willebrand factor, uptake of low-density lipoprotein, vimentin) could clearly be identified in ECV304, but not in T24 cells. Desmoglein and cytokeratin, both known as epithelial markers, were found in ECV304 as well as in T24 tells. However, differences were found for the two cell lines with respect to the type of cytokeratin: in ECV304 cells mainly cytokeratin 18 (45 kDa) is found, whereas in T24 cells cytokeratin 8 (52 kDa) is predominant. As we could demonstrate, the ECV304 cell line exposes many endothelial features which, in view of the scarcity of suitable endothelial cell lines, still make it an attractive in vitro model for endothelia.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

[A 68-year-old man with speech disturbance as the initial symptom followed by bradykinesia and dementia. Clinical conference].

We report a 68-year-old man with progressive speech disturbance and dementia. He was well until 1995, when he noted an onset of difficulty in speech. He was able to name simple objects and understand language, however, he showed great difficulty in spontaneous speech. In 1998, he visited our service. He was alert and oriented, but he showed moderate degree of dementia. He did not appear to have aphasia but he showed marked dysarthria and slurred speech. He showed limb-kinetic apraxia in his right hand. He showed moderate restriction in his vertical gaze, masked face, and dysphagia. He walked normally. No rigidity, ataxia, or abnormal involuntary movement was noted. He showed grasp response and he was bradykinetic. He was treated with levodopa without effect. His condition deteriorated slowly and he was admitted to our service because of fever on February 13, 1999. He was alert but almost mute. He was unable to look upward or downward. Oculocephalic response was preserved. Axial rigidity was noted but no limb rigidity was present. He walked with small steps. Retropulsion was present. Deep tendon reflexes were diminished and the plantar response was flexor bilaterally. Laboratory examinations were unremarkable and his fever went down within a few days by supportive treatment. He was discharged to his home, where his condition deteriorated further. He developed cardiopulmonary arrest on May 3, 1999 and was brought into ER again. Cardiopulmonary resuscitation was unsuccessful and he was pronounced dead at 7:30 in the morning on the same day. The patient was discussed in a neurological CPC. The chief discussant arrived at the conclusion that this patient had corticobasal degeneration. But he felt that the differential diagnosis from atypical progressive supranuclear palsy, in which cortical pathology and symptoms predominated as in corticobasal degeneration, would be extremely difficult. Most of the participants felt that this patient had corticobasal degeneration, but a few thought that he had atypical PSP. Post-mortem examination revealed asymmetric cortical atrophy, which was accentuated in the left motor cortical area. Microscopic examination of the precentral cortex revealed neuronal loss and gliosis. Ballooned neurons and astrocytic plaques were also seen. The substantia nigra showed marked neuronal loss. Neuropil threads were observed in the nigra. Those threads were positive for anti-tau immunohistochemistry. The internal segment of the globus pallidus, the subthalamic nucleus, and the cerebellar dentate nucleus showed mild to moderate neuronal loss. A few neurofibrillary tangle-positive neurons were seen in these structures. Neuropil threads were also seen throughout. Pathologic changes were consistent with the diagnosis of corticobasal degeneration. One of the participants pointed out that he was able to walk at the time when he was showing marked speech disturbance and limb-kinetic apraxia, which was rather unusual for PSP suggesting corticobasal degeneration.

Aged↗

[An ultrasound biomicroscopic study of eyes after non-penetrating trabeculectomy].

PURPOSES: We studied the control of intraocular pressure(IOP) by various types of blebs after non-penetrating trabeculectomy(NPT) and the difference between bleb formation after penetrating trabeculectomy(PT) and that after NPT. METHODS: The filtering blebs of 45 yeys from 40 patients after NPT were studied using ultrasound biomicroscopy. They were grouped into four types, and the space under the scleral flap was classified into three types. The filtering blebs and the space under the scleral flap were correlated with IOP level. RESULTS: Overall, 40% of the blebs were L(low-reflective) type, 16% H(high-reflective) type, 16% E (encapsulated) type, and 29% F(flattened) type, but in good IOP control cases 59% of the blebs were L type, 14% H type, 14% E type, and 14% F type. L type blebs were found in 94% of eyes with good IOP control. CONCLUSION: Though filtering blebs of the L type could produce sufficient IOP reduction, blebs after NPT showed a greater tendency to become flattened than after PT. Additional systematic therapy must be designed to maintain the L type of filtering blebs after NPT.

Glaucoma↗

[Persistent hyperplastic primary vitreous--a case report of adult onset acute angle-closure glaucoma].

BACKGROUND: We report a patient with persistent hyperplastic primary vitreous(PHPV) who presented with acute angle-closure glaucoma in his adult life. CASE: A 30-year-old man had an attack of acute angle-closure glaucoma associated with retrolenticular fibrous tissue, atrophic retina, and elongated cilliary process in his right eye. RESULT: Ultrasound biomicroscopy(UBM) study showed iris bowing, shallow anterior chamber, and elongated cilliary body which were being pulled by the retrolenticular mass. The posterior chamber was normal. CONCLUSION: Although the mechanisms of secondary angle-closure glaucoma in PHPV are complicated, we suspected pupillary block resulting from constriction by the retrolenticular mass in this case.

Acute Disease↗

Detection of tumor cells in blood using CD45 magnetic cell separation followed by nested mutant allele-specific amplification of p53 and K-ras genes in patients with colorectal cancer.

A new method for detecting circulating tumor cells that is based on magnetic-activated cell separation (MACS) and nested mutant allele-specific amplification (nested MASA) was evaluated in patients with colorectal cancer using the p53 and K-ras genes as genetic markers. By negative selection with anti-CD45 monoclonal antibody-conjugated supermagnetic microbeads, the proportion of tumor cells was enriched 9-fold. By the combination of MACS and nested MASA, 10 tumor cells in 10(7) normal peripheral blood mononuclear cells could be detected without false-positives. Using this method, we examined blood taken from the tumor drainage veins of 23 patients with colorectal cancer. Eighty-seven percent (20/23) of primary tumor tissues showed p53 and/or K-ras gene mutations. Forty-five percent (9/20) of patients with p53 and/or K-ras mutations in the primary tumor showed the same mutated genes in the blood samples. There was a significant association between the presence of p53 and K-ras gene mutation in the blood and tumor size, depth of invasion, and venous invasion. Blood gene mutation was detected in 80% (4/5) of samples from patients with synchronous liver metastases. Sixty percent (3/5) of patients with mutant genes in the blood developed asynchronous liver metastases after surgery. The overall survival of patients with p53 and/or K-ras gene mutation-positive findings in blood was significantly shorter than that of patients testing negative on Kaplan-Meier analysis. Our results suggest that the method may be useful for reliable detection of tumor cells circulating in the blood and may help to identify patients at high risk for relapse.

Adenocarcinoma↗

Precise measurement of dp elastic scattering at 270 MeV and three-nucleon force effects

The cross section, the deuteron vector A(d)(y) and tensor analyzing powers A(ij), the polarization transfer coefficients K(y('))(ij), and the induced polarization P(y(')) were measured for the dp elastic scattering at 270 MeV. The cross section and A(d)(y) are well reproduced by Faddeev calculations with modern data-equivalent nucleon-nucleon forces plus the Tucson-Melbourne three-nucleon force. In contrast, A(ij), K(y('))(ij), or P(y(')) are not described by such calculations. These facts indicate the deficiencies in the spin dependence of the Tucson-Melbourne force and call for extended three-nucleon force models.

Journal Article↗

Pre-existing histological type and developmental mechanism of mucinous noncystic carcinoma of pancreas.

Eleven cases with mucinous noncystic carcinoma (MC) of the pancreas were studied by histology and mucin immunohistochemistry, to elucidate the mechanism, or route of development, and pre-existing histological type of MC of the pancreas. These MCs were observed in close approximation to, or surrounding, intraductal papillary-mucinous carcinomas (IPMCs), and were centrally situated among ductal adenocarcinomas (DAs). Hence, the 11 cases originated from 8 IPMCs and 3 DAs. The mechanism and routes to MC were divided into four types as follows: IPMC directly invaded the stroma (4 cases), over-production of mucin in IPMC expanded the branches of the pancreatic duct possibly resulting in rupture (3 cases), DA underwent extreme mucinous degeneration (3 cases), and a recurrent form, as MC, at the surgical stump of IPMC (one case). The outcomes of MC cases with IPMC had variable survival rates, while those from DA had short durations. MUC immunoreactivity in MC was divided into three categories; anti-MUC1-positive only (2 IPMCs, 2 DAs), mixed anti-MUC1 and anti-MUC2-positive (3 IPMCs, one DA) and anti-MUC-positive only (3 IPMCs). Pre-existing MC histological types included both IPMC and DA. These two pre-existing types of MC involved mucin overproduction and mucinous degeneration. MUC immunoreactivity in MC revealed three patterns, which may be related to variable outcomes.

Adenocarcinoma↗

Pathogenesis and progression of human pancreatic fibrosis.

Fibrosis of the pancreas is one of the representative histopathological findings in cases of chronic pancreatitis. The pathogenesis and progression of pancreatic fibrosis are not yet fully understood. In this article, the pathogenesis, mechanism, and progression of pancreatic fibrosis are briefly reviewed based on our previous and most recent reports. Pancreatic fibrosis was classified into interlobular and intralobular types. In chronic alcoholic pancreatitis cases, fibrosis was mainly found in the interlobular, or perilobular, areas in a form of nodular pancreatitis. As for the mechanism of interlobular fibrosis, incomplete obstruction of the pancreatic duct and the appearance of the cells expressing alpha-smooth muscle actin, which is a marker for myofibroblasts, played an important role. In contrast, in intralobular fibrosis, alcohol intake was shown to have an effect in the initial stage of periacinar collagenization through the activation of myofibroblasts and severe damage to acinar cells. Progression of fibrosis occurred due to both duct obstruction and interlobular fibrosis admixed with myofibroblast proliferation. Therefore, myofibroblasts play an important role in both the mechanism and progression of pancreatic fibrosis.

Fibrosis↗

Cell cultures as tools in biopharmacy.

A survey is given on a few selected cell culture models that are used for transport studies. They are characterised for growth, transcellular electrical resistance and cytoarchitecture. The importance of standardisation in view of their use as transport models is documented. Their potential for studies on passive permeation and P-glycoprotein-mediated transport is explored and related to published data. Transport studies are presented that were performed in a two-chamber set-up, the Costar "vertical diffusion system". A series of non-homologous compounds showed similar permeability data (P(app)) in the different cell cultures. The origin of the cell type had no remarkable influence on passive transcellular permeation. MDCK cells, an epithelial cell line of canine kidney origin, are perfectly suited to screen for passive permeation. They have low expression of transporter proteins and low metabolic activity. In general, they probably represent the best-known epithelial cell line with respect to genetics as well as lipid and protein composition. MDCK cells are easy to handle. Transport experiments can be done between 7 and 14 days after seeding, when the stationary growth phase is reached. To screen for P-glycoprotein substrates, efflux and uptake studies were performed with mdr1-transfected MDCK cells (MDR1-MDCK) in a one-chamber system in the presence or absence of verapamil or cyclosporin A as inhibitor. Evidence is presented why the transfected cells, which express large amounts of P-glycoprotein, are not suitable for two-chamber transport studies.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Permeation studies in vitro and in vivo of potential radiopharmaceuticals with affinity to neuro receptors.

PURPOSE: To check the influence of structural characteristics on their permeation through the blood-brain barrier (BBB), a set of radioactive [99mTc]chelates bearing amine groups was synthesized and tested in vitro as well as in vivo. METHODS: Compounds with different log P and pKa values were obtained by complex forming reactions of [99mTc]pertechnetate with varying substituents. Transport was studied in rats and mice, as well as in an ECV304 cell culture model. RESULTS: In vitro higher permeation was found for compounds with electron attracting substituents in beta-position to the amine group (pKa values 7.4 to 8.3) than for those with more basic amine groups (pKa values > 8.9) even for similar log DH 7.4. In vivo brain uptake between 0.8 and 4.8% of the injected dose (ID) per organ was found for the former, whereas <0.4% ID were present for the latter. CONCLUSIONS: Three structurally diverse classes of [99mTc]chelates showed distinct patterns with regard to brain uptake in vivo and BBB permeability in vitro which could not be predicted by their lipophilicity alone. The close correlation between the data from rats and mice and those obtained with cell cultures render the ECV304 cells an attractive model for the screening of new compounds.

Animals↗

Monotypic epithelioid angiomyolipoma of the liver.

AIMS: Monotypic epithelioid angiomyolipoma is a recently recognized renal tumour, which is composed purely of epithelioid cells coexpressing markers of both smooth muscle differentiation and melanogenesis (HMB45). We report here the first case of monotypic epithelioid angiomyolipoma arising in the liver. CASE DETAILS: A 30-year-old woman without tuberous sclerosis complex (TSC) was incidentally found to have a hepatic mass by ultrasonography. Grossly, the resected tumour showed a nodule-in-nodule appearance, with large areas of haemorrhagic necrosis. Microscopically, the tumour was composed of pleomorphic epithelioid cells with clear, eosinophilic cytoplasm. Neither adipocytes nor abnormal vessels were recognized in the tumour. Immunohistochemically, the tumour cells were strongly positive for HMB45 and S100 protein, focally positive for desmin, vimentin and smooth muscle actin, and negative for epithelial markers (cytokeratins, EMA). Ultrastructural analysis showed numerous dense granules with some striated ones resembling melanosomes, myofilaments and pinocytic vesicles in the cytoplasm. Molecular analysis showed no allelic loss of the TSC2 region or 12 other chromosomal regions. The patient is free of disease over 1 year after the operation. CONCLUSION: We consider that this hepatic tumour is closely related to angiomyolipoma, and a counterpart of renal monotypic epithelioid angiomyolipoma.

Adult↗

Idiopathic gastric perforation in neonates and abnormal distribution of intestinal pacemaker cells.

BACKGROUND/PURPOSE: The etiology of idiopathic gastric perforation (IGP) in neonates is unclear. Interstitial cells of Cajal (ICC) express tyrosine kinase receptor C-kit, and act as gastrointestinal pacemaker cells. Stem cell factor (SCF) is a C-kit ligand and plays an important role in immune system homeostasis in the gastrointestinal tract. The authors hypothesized that abnormal distribution of ICC or SCF in the gastric wall (ie, abnormal motility or impaired immunity) could predispose the stomach to IGP. METHODS: Stomachs obtained at postmortem from neonates who died of IGP (n = 7) and other causes (control group; n = 10) were used. Biopsy sections were taken at random from various sites in the stomach, including macroscopically intact areas, and labeled immunohistochemically using antibodies to C-kit(a marker for ICC) and SCF. RESULTS: In all control specimens, ICC were present between the muscle layers and around the myenteric plexuses of the stomach wall. In contrast, ICC were absent in all biopsy sections from 3 of the 7 IGP stomachs. In the remaining 4 IGP stomachs, there were fewer ICC in the muscle layers compared with controls, and ICC were absent around the myenteric plexuses. The distribution of SCF immunoreactivity in IGP and control specimens was similar. CONCLUSION: The findings suggest that a lack of ICC (ie, gastric hypomotility) may be implicated in the etiology of IGP in neonates.

Analysis of Variance↗

An annular pancreas derived from paired ventral pancreata, supporting Baldwin's hypothesis.

An annular pancreas is a rare malformation. It is generally accepted that the ring formation originates from a single ventral pancreas, as suggested by Lecco. No reports of resected and/or autopsied annular pancreata derived from paired ventral pancreata, thus supporting Baldwin's hypothesis, have been published. We describe an annular pancreas originating from paired ventral pancreata, thus supporting Baldwin's hypothesis, and attempt to clarify the pathogenesis of an annular pancreas. The patient was a 1-day-old Japanese male newborn, born at 32 weeks of pregnancy. He died from respiratory failure owing to esophageal atresia the next day. Autopsy incidentally revealed an annular pancreas that was examined histologically. Multiple 4 microm thick serial sections were obtained from paraffin-embedded pancreatic tissue. Sections for histologic analysis were subjected to hematoxylin-eosin staining and pancreatic polypeptide immunostaining. An unusually large pancreatic duct encircled by pancreatic tissue ran around the duodenum, and the duct was confirmed to flow into the major papilla. The islets of the encircling pancreas were positive for pancreatic polypeptide. A normal main and accessory pancreatic duct were also identified. Histologic and immunohistochemical evaluation revealed that the ring formation originated from the left lobe of paired ventral pancreata. An annular pancreas that was investigated histopathologically and immunohistochemically and found to support Baldwin's hypothesis is described.

Esophageal Atresia↗