Biomedical subjects

Atsuyoshi Onitsuka

Publications and source records attributed to Atsuyoshi Onitsuka.

7 recordsLinked to original sources

PubMed2005

Escherichia coli O157 infection mimicking acute appendicitis: usefulness of computed tomography for differential diagnosis.

A 19-year-old man was admitted to our hospital with acute abdominal pain in the right lower quadrant. He had had mild diarrhea, of 1 day's duration, 2 days before admission. Although physical findings were consistent with a diagnosis of acute appendicitis, computed tomography findings showed marked wall thickening from the ascending colon to the cecum, findings which were similar to those in patients with hemorrhagic colitis due to Escherichia coli O157. Instead of emergency laparotomy, the patient was treated with antimicrobial agents, which led to rapid recovery. Diagnosis of intestinal infection due to E. coli O157 was established later, as serum antibody against lipopolysaccharide of E. coli O157 was positive. E. coli O157 infection should be included in the differential diagnosis of diseases that exhibit marked wall thickening of the right colon on CT in patients with acute abdominal pain in the right lower quadrant who have mild transient diarrhea.

Acute Disease↗

PubMed2003

Hilar cholangiocarcinoma associated with sarcoid reaction in the regional lymph nodes.

A 74-year-old woman was admitted to our hospital with a 2-week history of jaundice. Percutaneous transhepatic cholangioscopy revealed a nodular tumor originating in the upper part of the common hepatic duct, which was invading the confluence of the right and left hepatic ducts. Microscopic examination of biopsy specimens revealed adenocarcinoma. Abdominal ultrasonography and computed tomography demonstrated multiple enlarged lymph nodes around the extrahepatic bile duct and the common hepatic artery. Laparotomy revealed lymph node enlargement in the hepatoduodenal ligament, behind the pancreatic head, and along the common hepatic and left gastric arteries. Extended left hepatic lobectomy, caudate lobectomy, and resection of extrahepatic bile duct with extended lymph node dissection were performed. The histology of permanent specimen revealed no tumor metastasis but a sarcoid reaction in the lymph nodes. The patient is in good health 21 months after the operation, without any evidence of recurrence. This is the first successfully resected case of hilar cholangiocarcinoma associated with sarcoid reaction in the regional lymph nodes.

Aged↗

PubMed2003

Current practices in adult groin hernias: a survey of Japanese general surgeons.

The tendency to perform abdominal wall reinforcement using various types of mesh (tension-free repair) is increasing. A questionnaire to poll Japanese surgeons on their current surgical modalities for groin hernias was sent to 105 hospitals and was returned by 83 hospitals. The majority (83%) of responders to this survey supported the tension-free repair as a standard operation for adult groin hernias. Of these 69 tension-free repairs, the mesh-plug repair was the most frequent standard operation ( n = 53, 64%) and was performed by all responders. Ten (12%) opted for the prolene hernia system (PHS) repair as a standard operation and 52% of responders had experience of the PHS repair. Laparoscopic repair was performed as a standard operation by only one responder and was performed by only 34% of responders.

Adult↗

PubMed2003

Analysis of the T cell receptor V beta repertoire in 2,4,6-trinitrobenzenesulfonic acid induced colitis in mice.

The aim of this study was to analyze which types of T cells are at work and the specific nature of their response, using a mouse 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced colitis model. The response of T cells to TNBS was analyzed by anti-TNBS mixed-lymphocyte reaction. T cell clones were established by limiting dilution. Phenotypes and T cell receptor (TCR) V beta of T cells were analyzed by flow cytometry. Colitis was induced by administration of TNBS enemas, and lamina propria lymphocytes were isolated and analyzed. The proliferative responses to TNBS of spleen T cells were partially inhibited by the addition of antimouse CD4 or CD8 antibodies to the mixed-lymphocyte culture. Conversely, these were inhibited by the addition of both antibodies. Flow cytometric analysis showed that TCR V beta 14 T cells specifically increased in the CD8+ T cell population. We established CD8+ TCR V beta 14 T cell clones which were TNBS reactive and self-restricted. Investigation using lamina propria lymphocytes in TNBS-induced colitis revealed that the rate of CD8+ TCR V beta 14 T cells changed with histological inflammatory activity which also attained a peak on day 5 following enema administration. Both CD4+ and CD8+ T cell subsets responded to TNBS, and the rate of CD8+ TCR V beta 14 T cells changed with histological inflammatory activity in TNBS-induced colitis.

Animals↗

PubMed2002

Dielectric spectrogram for evaluating ischemic microstructural changes of the liver in simple cold preservation.

PURPOSE: Monitoring ischemic liver injury is important in liver transplantation. We previously reported that dielectric properties were correlated with tissue adenosine triphosphate during liver preservation; however, it is unknown what the changes in dielectric properties are based on. Using rats, we studied the relationship between dielectric parameters and microstructural changes in liver tissues during preservation. METHODS: We serially measured the percent decrease in conductivity and the percent increase in relative permittivity in rat livers, and determined the areas of cellular and extracellular components using a charge-coupled device microscope and an NIH image. Thereafter, we evaluated the relationship between dielectric parameters and microstructural changes in the liver tissues. RESULTS: A positive linear and exponential correlation was found between the percent decrease in conductivity and the percent decrease in extracellular components ( P < 0.01). A positive linear and exponential correlation was also found between the percent increase in relative permittivity and the percent increase in cellular components ( P < 0.01). CONCLUSIONS: Our results suggest that the serial changes in tissue conductivity and the relative permittivity reflect changes in liver tissue microstructures during cold preservation.

Animals↗

PubMedDate not supplied

Metastatic hepatoma originating from the pons hepatis presenting extrahepatic growth--classification of different patterns covering REX's recessus.

A metastatic liver carcinoma which developed from the pons hepatis and presented as an extrahepatic mass on ultrasonography and computed tomography is reported. There have been no other reports of hepatoma documenting the extrahepatic growth developed from the pons hepatis. Herein we study the frequency of the pons hepatis and classify the form of REX's recessus. Of 125 cases that underwent upper abdominal operation, 46 cases (38%) had nothing under REX's recessus (Type I), 48 cases (37%) had a fibrous tissue under REX's recessus (Type II), and 31 cases (25%) had a pons hepatis (Type III). In Type III, some cases suggested that the pons hepatis was ready to disconnect from side to side. We conclude that Type II is a modified form of Type III, and Type I is a modified form of Type II.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Minilaparotomy for early gastric cancer.

BACKGROUND/AIMS: From the experience of laparoscopic-assisted distal gastrectomy, it was considered that a gastrectomy with lymph node dissection could be performed through a minilaparotomy, placed as for gastroduodenostomy in laparoscopic-assisted distal gastrectomy. METHODOLOGY: Ten patients with early gastric cancer underwent gastrectomy with lymph node dissection via minilaparotomy. Minilaparotomy was performed via a seven-centimeter midline incision placed at the mid-upper abdomen. Two six-centimeter-wide Kent retractors were used to suspend the abdominal wall on each side, and a multipurpose surgical arm to retract the liver. The abdominal wound could be moved horizontally by pulling these retractors to the right or left. This movable wound allowed direct visualization of almost all the operative field for gastrectomy. RESULTS: No operation was converted to a standard open gastrectomy. The patients who had a tumor in the lower third of the stomach underwent complete D2 lymph node dissection. In the patients who underwent pylorus-preserving gastrectomy, near complete D2 lymph node dissection was performed. Mean operation time was 175 minutes. No significant complication was encountered. CONCLUSIONS: It was concluded that minilaparotomy could be used as an alteration to the standard open gastrectomy.

Adult↗