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Biomedical subjects

H Mishima

Publications and source records attributed to H Mishima.

At least 19 recordsLinked to original sources
PubMed2006

Expression and mutation of SMAD4 in poorly differentiated carcinoma and signet-ring cell carcinoma of the colorectum.

Poorly differentiated adenocarcinoma (Por) and signet-ring cell carcinoma (Sig) are rare but highly malignant types of colorectal cancer. To explore their genetic backgrounds we investigated TGF-beta type II receptor (TGF-beta RII) and SMAD4 in the TGF-beta signaling pathway, and to identify their mutator phenotype we examined microsatellite instability (MSI) status. Loss of SMAD4 expression was significantly more frequent in Por (12 of 38; 31%) and Sig (4 of 5; 80%) tumors than in well (Well) and moderately differentiated (Mod) carcinomas (p = 0.04, 0.003, respectively). Mutation of the SMAD4 gene was detected in 2 of 26 Por tumors. MSI was positive in 14 of the 38 Por tumors and in 1 of the 5 Sig tumors, but in none of the Well or Mod tumors examined. We also found mutation of TGF-beta RII, a putative target of MSI, in 10 of 35 Por tumors (28.6%), but in none of 3 Sig tumors. As a whole, about 50% of the Por tumors and 80% of the Sig tumors showed abnormalities of either TGF-beta RII or SMAD4 expression. This suggests that disruption of the TGF-beta signaling pathway may play a central role in the pathogenesis of Por and Sig tumors of the colorectum.

Adenocarcinoma↗
PubMed2005

Bile duct schwannoma developed in the remnant choledochal cyst-a case associated with total agenesis of the dorsal pancreas.

A 59-year-old Japanese woman was referred to our hospital due to upper abdominal pain. At the age of 44, she was diagnosed with a congenital choledochal cyst, Todani's type Ic. She then underwent bypass operation with end-to-side choledochojejunostomy with Roux-en-Y technique as well as cholecystectomy. Magnetic resonance cholangiopancreatography revealed an 'oval' shaped cystic lesion with a maximal diameter of 25 mm, which had been 'spindle' shaped with a maximal diameter of 18 mm, 15 years ago. It also showed an anomalous pancreaticobiliary ductal union. In addition, a complete absence of the dorsal primordia of pancreas was revealed by magnetic resonance image and computed tomography scan. The patient underwent the surgical exploration for the resection of the 'oval' shaped cystic lesion. Haematoxylin and eosin staining of the thin section of the resected cyst showed a compact spindle cell pattern which was compatible with schwannoma, Antoni type A, which was confirmed by immunocytochemical technique. We present a very interesting case showing choledochal cyst, anomalous pancreaticobiliary ductal union, total agenesis of the dorsal pancreas and late-development of bile duct schwannoma in the remnant choledochal cyst.

Abdominal Pain↗
PubMed2003

Realistic Virtual Endoscopy of the ventricle system and haptic-based surgical simulator of hydrocefalus treatment.

New methods and software tools for automatic extraction of the ventricle system from magnetic resonance imagery (MRI) data, ventricle part classification, and realistic texturing are proposed to support Virtual Endoscopy (VE). Volume- and surface-based medical atlases are intensively used as templates in the methods. The processed ventricle-related surfaces are then utilized in a haptic-based system, which provides a surgeon with several basic functions simulating "virtual treatment" of hydrocephalus.

Cerebral Ventricles↗
PubMed2001

New technique of laparoscopic-assisted excision of a cholecystocolic fistula: report of a case.

Cholecystocolic fistula is a rare complication of gallstone disease that is most commonly diagnosed at the time of surgery. It is generally considered to be a contraindication to laparoscopic cholecystectomy because of the difficulties involved in its management intraoperatively. Laparoscopic stapling or suturing techniques have been reported as feasible and safe methods for repairing such fistulas; however, these procedures are not always able to be performed due to technical difficulties. We exteriorized a cholecystocolic fistula through an umbilical incision, whereby it was repaired safely and easily. This report describes our new technique for managing a cholecystocolic fistula found incidentally during a laparoscopic cholecystectomy.

Cholecystectomy, Laparoscopic↗
PubMed2001

Chondrocyte apoptosis and regional differential expression of nitric oxide in the medial meniscus following partial meniscectomy.

Partial medial meniscectomy leads to tibial articular cartilage degeneration. Nitric oxide (NO) production increases with the development of osteoarthritis (OA) and has been shown to have a catabolic effect on chondrocytes. Since distribution of chondrocytic and fibroblastic cell types within the total cell population comprising meniscus is region-specific, we compared NO production in the peripheral and central regions of the medial meniscus 12 weeks after partial medial meniscectomy and assessed chondrocyte apoptosis and NO production in the tibial articular cartilage. Additionally, transcriptional gene expression of inducible nitric oxide synthetase (iNOS) and immunohistochemical staining of nitrotyrosine were examined. The results showed that following partial medial meniscectomy, NO production in the central region of the medial meniscus and in the tibial articular cartilage were significantly higher than respective NO levels in normal and sham-operated controls. Reverse transcription polymerase chain reaction (RT-PCR) revealed a high transcriptional expression of the iNOS gene in the central region of the meniscus and in tibial articular cartilage following partial medial meniscectomy. Nitrotyrosine immunoreactivity was prominent in the central region of the medial meniscus and in the deep layer of the tibial articular cartilage and apoptotic cells were also detected in situ in the superficial zone of the tibial articular cartilage and central regions of the medial meniscus following partial medial meniscectomy. These observations suggest that the central region of the meniscus is responsible for NO synthesis associated with apoptosis in both meniscal and articular cartilage cells following partial meniscectomy.

Animals↗
PubMed2001

High-resolution electron microscopy of the crystallites of fossil enamels obtained from various geological ages.

To elucidate the stability of the central dark line (CDL) in biologically induced hydroxyapatite crystals, we examined the diagenetic changes on the microstructures of the crystallites during the course of fossilization. Using transmission electron microscopy, we investigated the enamel crystallites of fossil animals of various geological ages ranging from Pleistocene to Cretaceous. Electron micrographs indicated that the microstructures and lattice images of each crystallite in fossil enamels were well-preserved regardless of the thickness of the enamel layer, and the presence of CDLs in fossil enamel crystals was also confirmed. The results indicated that the microstructure of hydroxyapatite crystals containing lattice images of CDLs appear stable during long geological periods. In addition, we conclude that the existence of lattice images in apatite with CDLs may be an indicator for the assessment of the evolution of dental enamel from fossil remains.

Animals↗
PubMed2001

[Evaluation and multivariate statistical analysis of factors influencing patient adherence to ophthalmic solutions].

In this study, factors influencing patients adherence to ophthalmic solutions were investigated. Seventy-one subjects (aged 62.3 +/- 15.5 years) were randomly selected from patients admitted to the Ophthalmology Department at Hiroshima University Hospital. The patients (n = 71) completed questionnaires, which were evaluated by clinical pharmacists. The patient group to which the ophthalmic solutions were applied once or twice daily was more compliant than other patient groups (p = 0.00057). A multivariate statistical analysis revealed that the factors influencing patients adherence were the number of ophthalmic solutions used, patient age, taste, administration intervals, the number of drops used, and hand washing before the application of ophthalmic solutions. Patients who understood the significance of the medication made fewer mistakes than those who understood only the route of administration but not the significance. In conclusion, our study shows that patient counseling should emphasis the significance of the administered medicine as well as the route of administration.

Aged↗
PubMed2001

Oxidative stress by visible light irradiation suppresses immunoglobulin production in mouse spleen lymphocytes.

In this study, we attempted to induce the oxidative stress in mouse spleen lymphocytes with visible light irradiation and examined the effects of lipid peroxidation on immunoglobulin (Ig) production. The spleen lymphocytes were isolated from 8-week-old male balb/c mice and irradiated with 300 W visible light. When the cells were cultured for 72 hr, Ig contents in culture supernatants were decreased gradually by irradiation for over 30 min. The cell viability was also lowered by the irradiation. Intracellular phosphatidylcholine hydroperoxide (PCOOH) levels and thiobarbituric acid-reactive substances (TBARS) values in culture supernatants were measured as indices of lipid peroxidation and we found that Ig production by mouse spleen lymphocytes was suppressed accompanied with the progress of peroxidation of intracellular phospholipids. Cell membrane fluidity was also significantly decreased, but the intracellular Ig level was not changed in the irradiated cells. These results suggest that the peroxidation of intracellular lipids is a cause of the suppression of Ig production by mouse spleen lymphocytes via lowering cell viability and suppressing Ig synthesis and secretion.

Animals↗
PubMed2001

[Anterior turbinectomy: experimental and clinical study].

INTRODUCTION: Minimal cross-sectional areas situated at the anterior end of the inferior turbinate have the most influence on nasal patency. To improve persistent nasal obstruction, 2 types of inferior turbinectomies--conventional complete resection including the anterior and posterior mucosa and anterior resection of the anterior mucosa--were conducted and preoperative and postoperative nasal patency and stuffy sensation were compared and analyze. OBJECTS AND METHODS: Cases undergoing 2 types of turbinectomies between July 1997 and March 2000 numbered 63--conventional in 32 (64 sides) and anterior in 31 (62 sides). Anterior, posterior, and total nasal volume and minimal cross-sectional area were evaluated pre- and postoperatively using an acoustic rhinometer. The stuffy sensation was similarly evaluated by the visual analog scale (VAS). RESULTS: All nasal volumes showed postoperative increase under conventional treatments. Anterior and posterior volumes significantly increased under anterior treatment. Comparing the results of postoperative volume posterior volume was significantly larger under conventional treatment than under anterior treatment. Stuffy sensation significantly improved by VAS in both types of turbinectomy, with no significant difference between them. CONCLUSION: Anterior treatment to solely increase nasal volume at the minimal cross sectional area showed equal postoperative improvement in VAS under conventional treatment.

Acoustics↗
PubMed2001

[The influence of septal perforation on measurement by acoustic rhinometry].

The influence of septal perforation on results of acoustic rhinometry was studied using cases of septal perforation and a human-nose model. Acoustic rhinometry was conducted before and after closing the perforation (average 16 mm in diameter, 23 mm from the nostril) by thin cotton patches in 33 cases (19 men and 14 women). The decrease in cross-sectional area and volume after closure was statistically significant. A human-nose model with septal holes ranging from 5, 10, 15, to 20 mm and locations ranging from 20, 40, to 50 mm from the nostril was studied by acoustic rhinometry. Our results suggest that the effect of perforations on the measurement is much greater in anterior perforations than in posterior perforations.

Acoustics↗
PubMed2000

Gastrointestinal stromal tumor of the rectum with activating mutation of c-kit: report of a case.

Nonepithelial malignancies of the large bowel are rare. A new disease entity, gastrointestinal stromal tumors, has attracted attention among primary mesenchymal tumors of the gastrointestinal tract. Here we present a case of spindle-cell sarcoma of the rectum, lacking either smooth muscle cells or neural elements. Immunohistochemical findings and sequencing of the c-kit proto-oncogene diagnosed this tumor as a malignant gastrointestinal stromal tumor of the rectum.

Female↗
PubMed2000

Elevated interleukin-12 in pseudosynovial fluid in patients with aseptic loosening of hip prosthesis.

Loosening of a prosthesis is a major problem in total joint arthroplasty. To assess levels of cytokines in patients with such loosening, we measured the pseudosynovial fluid concentration of the following cytokines; tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1beta, IL-4, IL-6, IL-10, IL-12, matrix metalloproteinase (MMP)-1, and MMP-3. We examined the pseudosynovial fluid in patients with a loose hip prosthesis (group A; n = 8) and the synovial fluid in patients with osteoarthritis (OA) of the hip (group B; n = 18) using enzyme-linked immunosorbent assays. The mean concentration of IL-12 was significantly higher in group A than in group B (P < 0.01). Also, we found a significant (P < 0.05) correlation between the concentration of IL-12 and the concentration of MMP-1 in the patients with prosthesis loosening. The concentrations of TNF-alpha, IL-1beta, IL-4, IL-6, IL-10, IFN-gamma, MMP-1, and MMP-3 appeared to be similar in the two groups, although the small number of samples available precluded us from determining that there was no significant difference. The present study is the first to report elevated IL-12 levels in the pseudosynovial fluid of patients with a loose prosthesis. The immunoregulatory effect of IL-12 against wear particles could play an important role in causing loosening of the prosthesis.

Aged↗
PubMed2000

Effect of dietary conjugated linoleic acid on lipid peroxidation and histological change in rat liver tissues.

The effect of dietary conjugated linoleic acid (CLA) on hepatic lipid parameters in Sprague-Dawley rats was examined. When rats were fed a diet containing CLA at 0 (control), 1, or 2% of the weight of the amount of food given for 3 weeks, the liver weight exhibited a slight increase in the CLA-fed groups, although the difference was not significant. Lipid accumulation in the hepatocytes of CLA-fed rats was also demonstrated by electron microscopic observation. In addition, the liver thiobarbituric acid reactive substances levels were significantly higher in the 2 wt % CLA group than in the other two dietary groups, and the levels of phosphatidylcholine hydroperoxide were higher in CLA-fed groups when compared to that of the control group. On the other hand, the serum lipid peroxide levels were comparable among all three dietary groups. Levels of triglycerides in the white adipose tissue (WAT) and serum nonesterified fatty acid (NEFA) were reduced in a CLA-dose-dependent manner. CLA was shown to accumulate in the WAT much more than in the serum or liver. These results suggest that CLA accelerates the decomposition of storage lipids in WAT and the clearance of serum NEFA levels, resulting in lipid peroxidation and a morphological change in the liver.

Adipose Tissue↗
PubMed2000

[Nasal foreign bodies in 299 cases].

Although nasal foreign bodies very commonplace in daily clinical practice, their simplicity in pathology and diagnosis is so unique that case reports based upon a large number have been rather scarce. We report 299 verified cases of nasal foreign bodies seen during the past 13 years from January 1986 to December 1998, at our institute, together with clinical and statistical analysis. The total number of first visits during the surveyed period was 55,312 and nasal foreign bodies comprised 0.54%. Of these 217 subjects (72.6%) appeared in emergencies. Man comprised 172 (58%) and woman 127 (42%), with the right side comprising 166 cases (57%), the left side 123 (42%) and bilateral 3 cases (1%). In monthly distribution, cases are more often seen in November and December and less often seen in January, with the monthly average being 25. In age distribution, the majority were seen in those under 10 years old, excluding 6 cases. The average age was 4.0 and the range 1 month to 81 years. In the majority of cases, foreign bodies remained only a short time (with in 24 hour) but in 15 cases stayed rather a long time (over 24 hour). In specificity, the majority of foreign bodies were toys, with plastic bullets used with air guns most frequent, in 46 cases (15.3%), followed by beads in 36 cases (12.0%). Other foreign bodies seen comparatively often were pieces of tissue paper, buttons, and plastic toys components.

Adolescent↗
PubMed2000

Application of high resolution microfocus X-ray CT for the observation of human tooth.

The calcification degree of extracted human teeth was observed by using high resolution microfocus X-ray CT. As samples, upper and lower first premolars extracted from a 21-year-old female were used. The computed tomograms were produced by high resolution microfocus X-ray CT with a open vacuum X-ray source, rotating sample stage, and image sensor. The distinction between enamel and dentin was very clear, and the shape of the pulp cavity was also clearly identified. The secondary dentin was visible in the circumpulpal dentin. The color map displays showed the heterogeneity of the calcification degree not only in the dentin but also in the enamel. The enamel was divided into three layers according to the calcification degree. High resolution microfocus X-ray CT was very useful for the observation of the internal structure of human teeth without destroying the samples.

Adult↗
PubMed2000

[Effect of stellate ganglion block on human retinal blood flow].

PURPOSE: The effect of stellate ganglion block (SGB) on human retinal blood flow was evaluated. METHODS: We measured the diameter of the retinal artery and vein, and retinal venous flow rate by laser speckle retinal blood flow meter simultaneously in 11 eyes of 11 normal volunteers. RESULTS: The reliable data from 9 eyes of 9 person were used for analysis. SGB did not change the blood pressure, heart rate, retinal arterial diameter, or venous diameter. However SGB increased retinal blood velocity significantly from 9.9 +/- 1.6 (mean +/- standard deviation) mm/s to 11.1 +/- 1.5 mm/s (p < 0.01). Intraocular pressure decreased from 12.3 +/- 2.1 (mean +/- standard deviation)mmHg to 9.4 +/- 2.2 mmHg after SGB (p < 0.01). There was no relationship between the change of ocular perfusion pressure and that of retinal venous blood velocity. CONCLUSION: SGB increased the retinal venous blood velocity without changing the retinal vessel diameter.

Adult↗
PubMed2000

[Case report--efficacy of short-term intraarterial 5-fluorouracil for liver metastasis from colorectal cancer].

Hepatectomy has the highest cure rate among the various methods for treating liver metastasis from colorectal cancer. We previously reported that continuous hepatic arterial infusion (HAI) of 5-FU is effective for improving the prognosis of patients with liver metastasis. In this study, we examined the efficacy of short-term continuous HAI of 5-FU for treating liver metastasis from colorectal cancer. A 57-year-old woman with a solitary liver metastasis from rectal cancer was treated by continuous HAI of 5-FU (1,000 mg/day) for 6 days. Her elevated serum CEA level (20.7 ng/ml) then returned to normal. Computed tomography revealed a decrease of 55.6% in the size of the liver tumor. Partial segmentectomy (S7) was subsequently performed. Histological examination of the resected tumor showed marked degeneration, necrosis, fibrosis, and calcification with viable moderately differentiated adenocarcinoma cells. These results suggest that preoperative HAI of 5-FU is safe and worth trying in patients with liver metastasis from colorectal cancer.

Adenocarcinoma↗