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T Kuroda

Publications and source records attributed to T Kuroda.

At least 127 records · Page 7Linked to original sources
PubMed1999

[A case of glomangioma of the stomach].

Glomus tumor of the stomach is still a rare disease. In Japan, till now, only 78 cases have been reported as far as we look over the literatures. We report a case of glomangioma of the stomach. The patient is a 44-years old female who underwent a medical examination and pointed out a gastric submucosal tumor, but she had no symptoms and admitted for operation. The endoscopical finding was a submucosal tumor as large as 4 cm, and the result of biopsy was chronic atrophic gastritis. So typical gastrectomy was performed without a definite diagnosis. In the cross section, the tumor was clearly bounded gastric mucosa by a white membrane, and the center of the tumor was spongy. By patho-histological and electro-microscopic study, we diagnosed that the tumor was glomangioma in the classification of Weiss & Enzinger. The patient was getting on well after the operation and left the hospital on the 29th day.

Adult↗
PubMed1999

Condylar resorption 2 years following active orthodontic treatment: a case report.

We recently treated a patient with degenerative disease of the temporomandibular joint. A healthy, 12-year-old female with bilateral high maxillary canines presented for orthodontic treatment. Two years after active orthodontic treatment, at age 17, symptoms in her temporomandibular joint manifested and progressed. By the time she revisited our hospital at age 21, the patient had developed an anterior open bite with a long, slender facial appearance. Cephalometric analysis showed shortening of the ramus and backward and downward rotation of the mandible. Imaging studies revealed severe deformity and resorption of the bilateral condyles. Her occlusal and morphologic changes seemed to be caused by degenerative disease of the temporomandibular joint.

Adolescent↗
PubMed1998

Studies on Methicillin-Resistant Staphylococcus aureus Bacteremia Due to Laboratory Medical Analysis.

We encountered 64 patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia between April 1993 and March 1994. Mean patient age was 54 years. There were 46 males and 18 females. Underlying diseases mainly consisted of traffic accident (10 patients), valvular heart disease (5 patients), chronic renal failure (5 patients), leukemia (5 patients), pneumonia (3 patients), and malignant lymphoma (3 patients). The common clinical laboratory findings of MRSA bacteremia included decreses in total protein, albumin and hemoglobin as well as increases in white blood cells (neutrophils) and C reactive protein. In particular, an increase in C reactive protein by 10 mg/dl or more may be useful for diagnosing bacteremia. Laboratory findings were compared between surviving and non-surviving patients. There were significant differences in albumin, cholesterol, bilirubin, creatinine, and CRP. In 18 patients (28.1%), bacteremia was caused by infection due to contamination of central venous catheters. Since medical treatment with intra-vascular devices may cause bacteremia, sufficient caution is needed.

Journal Article↗
PubMed1998

Synthesis and structure-activity relationships of 7-(2-aminoalkyl)morpholinoquinolones as anti-Helicobacter pylori agents.

A series of the titled compounds was synthesized and tested for anti-Helicobacter pylori activities. We discovered Y-34867 having the most potent activity against Helicobacter pylori among the quinolones tested along with high photostability. Furthermore, Y-34867 showed an excellent therapeutic effect in the experimental Helicobacter pylori infected Mongolian gerbil model.

4-Quinolones↗
PubMed1998

Identification of two essential arginine residues in UhpT, the sugar phosphate antiporter of Escherichia coli.

Three lines of evidence indicate that arginine-46 (R46) and arginine-275 (R275) are essential to the function of UhpT, the Pi-linked antiport protein of Escherichia coli. A role for arginine was initially suggested by the sensitivity of UhpT to inhibition by 2,3-butanedione, an arginine-directed probe. Since the presence of substrate protected against this inhibition, this work further suggested that arginine(s) may lie at or near the UhpT active site. In other work, each UhpT arginine was examined individually by using site-directed mutagenesis to generate a cysteine or a lysine derivative. With two exceptions (R46, R275), all arginines could be replaced by either cysteine (10 of 14 residues) or lysine (12 of 14) without loss of function, implicating R46 and R275 as essential to UhpT function. This idea was strengthened by examining a multiple alignment of the eleven known UhpT-related proteins (>/=30% identity). That alignment showed R46 and R275 were two of the only three arginines strongly conserved in this group of proteins. Considered together, these different approaches lead us to conclude that UhpT and its relatives have only two arginine residues (R46, R275) whose presence is essential to function. Prior biochemical work had placed R275 at the external entrance to the translocation pathway, and a symmetry argument emerging from the multiple alignment suggests a similar position for R46. Accordingly, by virtue of their locations at the entrance to this pathway, we speculate that R46 and R275 function in establishing substrate specificity.

Amino Acid Sequence↗
PubMed1998

Cloning and sequencing of a novel Na+/H+ antiporter gene from Pseudomonas aeruginosa.

We cloned a gene for Na+/H+ antiporter from chromosomal DNA of Pseudomonas aeruginosa. Introduction of the gene into host Escherichia coli mutant cells lacking all of the major Na+/H+ antiporters enabled the cells to grow in the presence of 0.2 M NaCl, although the original host cells could not. Membrane vesicles prepared from cells of the transformant possessing the cloned gene showed Na+/H+ antiport activity. As a result of DNA sequencing, we found one open reading frame (nhaP). The deduced amino acid sequence suggests that the Na+/H+ antiporter (NhaP) of P. aeruginosa consists of 424 amino acid residues with molecular mass of 45486 Da, and hydropathy analysis suggested the presence of 12 putative transmembrane domains. We found no bacterial Na+/H+ antiporter which showed significant sequence similarity with the NhaP in the protein sequence database. The NhaP showed partial sequence similarity with animal Na+/H+ exchangers. Thus, the NhaP of P. aeruginosa is unique among bacterial antiporters.

Amino Acid Sequence↗
PubMed1998

Patch clamp studies on ion pumps of the cytoplasmic membrane of Escherichia coli. Formation, preparation, and utilization of giant vacuole-like structures consisting of everted cytoplasmic membrane.

Formation of giant protoplasts from normal Escherichia coli cells resulted in the formation of giant vacuole-type structures (which we designate as provacuoles) in the protoplasts. Electron microscopic observation revealed that these provacuoles were surrounded by a single membrane. We detected inner (cytoplasmic) membrane proteins in the provacuolar membrane but not outer membrane proteins. Biochemical analyses revealed that the provacuoles consist of everted cytoplasmic membranes. We applied the patch clamp method to the giant provacuoles. We have succeeded in measuring current that represents inward movement of H+ because of respiration and to ATP hydrolysis by the FoF1-ATPase. Such current was inhibited by inhibitors of the respiratory chain or FoF1-ATPase. This method is applicable for analyses of ion channels, ion pumps, or ion transporters in E. coli or other microorganisms.

Cytoplasm↗
PubMed1998

A new Na+/H+ antiporter, NhaD, of Vibrio parahaemolyticus.

A gene encoding an Na+/H+ antiporter was cloned from chromosomal DNA of Vibrio parahaemolyticus, a slightly halophilic bacterium, and expressed in Escherichia coli cells. The gene enabled mutant E. coli cells, which were unable to grow in the presence of 10 mM LiCl (or 0.2 M NaCl) because of the lack of major Na+(Li+)/H+ antiporters, to grow under such conditions. We detected Na+/H+ antiport activity due to the gene in membrane vesicles prepared from E. coli cells that harbored the plasmid carrying the gene. Li+ was also a substrate for this antiporter. Activity of this antiporter was pH-dependent with highest activity at pH 8.5 to 9 and no activity at 7.0 to 7.5. Restriction mapping and a Southern blot analysis revealed that the cloned gene was different from the nhaA and the nhaB of V. parahaemolyticus. We designated the gene nhaD. The gene was sequenced, and the amino acid sequence of the NhaD protein was deduced. The NhaD is a unique Na+/H+ antiporter with respect to the primary structure compared with known Na+/H+ antiporters.

Amino Acid Sequence↗
PubMed1998

Longitudinal follow-up of pulmonary function after lobectomy in childhood - factors affecting lung growth.

We examined the changes in pulmonary function values in 27 patients who underwent a lobectomy due to cystic lung disease and compared the results regarding such factors as disease type, age at operation, and preoperative infections. Percent vital capacity (%VC) decreased immediately after lobectomy, but recovered to normal values within 2 postoperative years and remained within or above the normal range. The ratio of residual volume to total lung capacity (RV/TLC) rose temporally with the increase in %VC, but then remained normal after 2 postoperative years. There was no difference in %VC and RV/TLC between diseases, while bronchial atresia showed a significantly lower correlation with percent of forced expiratory volume at 1 s. The older group operated upon at over 4 years of age and the group that had infections before operation showed relatively low %VC and high RV/TLC. Some patients demonstrated extremely low %VC along with funnel chest deformities. Our study suggests that overinflation of the remaining lung compensates VC in the early period after lobectomy while subsequently alveolar multiplication occurs. Factors affecting compensatory lung growth were considered to be operation later than 4 years of age, preoperative infection, and a thoracic deformity.

Child↗
PubMed1998

Multiple carcinoids of the duodenum accompanied by type I familial multiple endocrine neoplasia.

A case of multiple carcinoid tumors of the duodenum accompanied by familial multiple endocrine neoplasia is reported. A 46-year-old man with duodenal polyps discovered during a mass screening was followed up for 5 years. In August 1994, a histological examination revealed carcinoid tumors, and he was thus referred to our hospital for surgery. He underwent a parathyroidectomy and cholecystectomy for primary hyperparathyroidism and cholecystolithiasis, respectively. The patient's sister had also undergone a parathyroidectomy and distal pancreatectomy for primary hyperparathyroidism and insulinoma of the pancreas. In addition, his two children were also followed up for hypercalcemia. A serum examination of the patient revealed high levels of somatostatin and pancreatic polypeptide, but normal levels of gastrin and serotonin. In November 1994, a pancreaticoduodenectomy with a D2 lymph node dissection was performed. The macroscopic findings of the resected specimen showed multiple polypoid lesions with delles on the top, measuring 3 to 15 mm in size throughout the duodenum. A microscopic examination revealed the tumor to have infiltrated into the submucosa extensively, and an immunohistochemical analysis also demonstrated the tumor cells to be positive for somatostatin, but not for pancreatic polypeptide. After surgery, the serum level of somatostatin returned to normal but the pancreatic polypeptide remained high. The post-operative course was uneventful, and the patient remains in good health.

Carcinoid Tumor↗
PubMed1998

Immunohistochemical findings type I and type II collagen in prenatal mouse mandibular condylar cartilage compared with the tibial anlage.

In growing animals the mandibular condylar cartilage serves not only as an articular but also as a growth cartilage, yet, condylar cartilage has some characteristic features that are not found in growth cartilage. For example, some reports suggest that type I collagen, which is not seen in the growth plate cartilage of long bones, is present in the extracellular matrix of condylar cartilage postnatally. Here, the condylar and limb bud cartilage of fetal mice was examined. The distribution of type I and type II collagen in condylar cartilage was already different from that in the limb bud at the first appearance of the cartilage. Type I collagen was demonstrated in the extracellular matrix of the condylar cartilage that first appeared on day 15 of gestation. However, the reaction for type II collagen was much weaker than that for type I collagen. On day 18 of gestation, type I collagen was still found throughout the cell layers but became gradually weaker with depth. Type II collagen was limited exclusively to the deeper layers at this stage. These findings are different from those in the limb bud cartilage, indicating a characteristic feature of the cells in the condylar cartilage present from the prenatal period.

Animals↗
PubMed1998

The combined method: a novel access technique for fetal endoscopic surgery.

BACKGROUND/PURPOSE: To develop practical and less invasive techniques for fetal endoscopic surgery, new methods of lifting the uterine wall to allow fetal surgery without maternal laparotomy were developed and assessed. METHODS: Fetal endoscopic surgical procedures, including tracheostomy and umbilical vascular cannulation, were performed using one of the three methods to enter the uterus without maternal laparotomy in pregnant goats (n = 6; 105 to 115 days' gestation): (1) direct uterine lifting with an air-cushion device; (2) indirect uterine lifting, in which the uterine wall was fixed to the maternal abdominal wall using balloon tip ports inserted percutaneously by Seldinger's method, then the maternal abdomen was lifted mechanically; and (3) combined method, in which low pressure CO2 (5 mm Hg for initial inflation and 2 mm Hg for maintenance) was insufflated into the uterus in addition to the indirect uterine lifting cited above. RESULTS: The direct uterine lifting caused massive injury of myometrium and uterine membranes. The creation of intrauterine space and the protection of the membranes were not accomplished effectively by the indirect uterine lifting only. The combined method provided the adequate intrauterine space and excellent endoscopic visibility for completion of the endoscopic procedures with minimal uterine injury. CONCLUSION: The fetal endoscopic surgery may be accomplished simply and safely by the combined method, a novel technique of uterine lifting to allow fetal surgery without maternal laparotomy.

Animals↗
PubMed1998

Granulocyte-colony stimulating factor improves suppressed neutrophilic phagocytosis against hypernatremic condition.

Phagocytic activity is an important function of neutrophils in the host defense against burn wound infection. In a previous report we demonstrated hypernatremic suppression of neutrophils at sodium concentrations comparable to these in the zone of stasis in the burn wound. At this site the osmotic pressure will be elevated as a result of several factors, especially to increased water loss from the burn wound surface. In this study the effect of granulocyte-colony stimulating factor (G-CSF) on phagocytic activity of human neutrophils against hypernatremic suppression is investigated in vitro. In the G-CSF group 150 ng of G-CSF was added to four blood samples (5 ml each). Phagocytic activities of the control group (n = 10) showed 88.3+/-4.1 per cent (means+/-SD) at 140 mmol/l of sodium concentration, 68.2+/-6.9 at 180, 57.6+/-10.1 at 220, and 48.6+/-8.6 at 260 mmol/l. The G-CSF group showed 88.2+/-7.0 at 140, 79.9+/-9.4 at 180, 71.4+/-7.4 at 220, and 56.5+/-14.1 at 260 mmol/l. At 180 and 220 mmol/l significant differences were recognized. Results of this study suggest a favourable effect of G-CSF on suppressed neutrophils under the hypernatremic conditions.

Flow Cytometry↗
PubMed1998

Inhibition of masseteric electromyographic activity during oral respiration.

Although the effects of oral respiration on the growth and development of craniofacial structure have been studied previously, little is known about how altered respiration affects the activity of the jaw-closing muscles. Obstruction of the nasal airway in the cat significantly inhibited the masseteric stretch reflex and discharges of masseteric motor units but did not affect the electromyographic activity of the diaphragm. This inhibition was greater during inspiration than during expiration. In addition, the amplitude of the masseteric monosynaptic reflex elicited by electrical stimulation of the mesencephalic trigeminal nucleus showed no significant change in association with the altered respiratory mode. These findings suggest that masseteric electromyographic activity is inhibited during oral respiration and that the gamma-system is involved in this inhibition.

Action Potentials↗
PubMed1998

Immunochemical and biochemical characteristics of enamel proteins in hypocalcified amelogenesis imperfecta.

Amelogenesis imperfecta is a hereditary disease of the enamel that is unassociated with generalized defects. Cases of the condition are clinically classified into three groups: hypoplastic, hypomaturation, and hypocalcified. In this study, soluble protein fractions of the enamel from three patients with hypocalcified amelogenesis imperfecta were examined through the use of immunochemical and biochemical techniques. In immunochemical analyses done with a polyclonal anti-amelogenin antibody, all samples from enamel in which there was amelogenesis imperfecta were found to contain considerable amounts of amelogenin peptides. When an enamel sample from one patient was examined by Western-blot transfer and immunobinding analysis, the amelogenin fraction was found to consist of a 26-kDa molecule thought to be normally present in the outer layer of secretory-stage enamel. This enamel was also found to contain albumin as one of the major constituents of the protein fraction. These results suggest that hypocalcified amelogenesis imperfecta may in part be caused by a disturbance in matrix protein degradation during the maturation phase.

Adolescent↗
PubMed1998

Effects of a novel elastase inhibitor, ONO-5046, on nephrotoxic serum nephritis in rats.

ONO-5046 is a potent, specific and intravenously active inhibitor of neutrophil elastase. To examine the role of elastase in glomerulonephritis, we tested the effects of ONO-5046 on nephrotoxic serum (NTS) nephritis in a rat model of the disease in humans. Rats were administered ONO-5046 or phosphate-buffered saline (PBS) intraperitoneally 24 hours prior to injection of NTS, and they were then given equal doses of ONO-5046 or PBS three hours and 1, 2, 3, 4, 5 and 6 days later. Compared with the control groups, ONO-5046 significantly reduced proteinuria and hematuria, and suppressed the formation of crescentic glomeruli in a dose-dependent manner. Our results suggest that neutrophil elastase participates in NTS nephritis by degrading glomerular basement membrane proteins, and that the elastase inhibitor, ONO-5046, suppresses crescentic formation and glomerular injury caused by elastase.

Animals↗
PubMed1998

Pirfenidone improves renal function and fibrosis in the post-obstructed kidney.

BACKGROUND: Pirfenidone (PFD) is a novel anti-fibrotic agent that can prevent and even reverse extracellular matrix accumulation in several organs, as shown by experimental and clinical studies. Unilateral ureteral obstruction (UUO) is a well-characterized model of experimental renal disease culminating in tubulointerstitial fibrosis. METHODS: UUO or sham-operated rats were administered PFD (500 mg/kg/day) in their food for 21 days to examine the effect on collagen production. The renal function was measured in the kidney after release of obstruction which had been maintained for one week to examine the effects of PFD on restoration after renal dysfunction. RESULTS: The collagen content detected by hydroxyproline progressively increased in kidney with UUO for 21 days. These increases were significantly suppressed by administration of PFD. PFD had no effect on collagen production in sham-operated rats. Expression of mRNA for type IV and I collagen and matrix metalloproteinase-2 in the cortex increased with UUO, but was inhibited by PFD treatment. The levels of cortical transforming growth factor-beta (TGF-beta) mRNA progressively rose with UUO for 21 days, but this increase also could be suppressed by PFD. Inulin clearance of the obstructed kidney was markedly depressed and remained low at five weeks after release. A progressive increase in hydroxyproline content was also observed in the post-obstructed kidney despite the release of obstruction. Administration of PFD following the release not only attenuated collagen accumulation, but also induced recovery of the impaired renal function. CONCLUSIONS: These results demonstrate that PFD can attenuate both renal fibrosis and renal damage in this model, and suggest that PFD can be clinically useful for preventing progressive, irreversible renal failure.

Administration, Oral↗