Education and research in the division of biomedical and engineering technology

The department of Laboratory Science in the Faculty of Medicine at Kyoto University is committed to the development of medicine and medical care for the 21st century. We consider it our mission to contribute to the well being of the entire human race, and we seek students who wish to uphold these ideals. The general field of our Laboratory Medicine may be divided into three major categories; namely, basic and clinical laboratory medicine, biomedical and engineering technology, and medical care for patients and health. Health care relates to bolstering human health from a broad global perspective that encompasses the aspects of environment, health and welfare, and disease prevention.     

The first case of robotic-assisted transabdominal retrorectus repair for incisional hernia in Japan

Extraperitoneal mesh repair for ventral hernia has garnered attention and its rate has been increasing due to concerns for the potential complications of intraperitoneal mesh repair. Recently, robotic-assisted ventral hernia repair is highlighted as a solution to the technically demanding nature of laparoscopic transabdominal or enhanced-view totally extraperitoneal retrorectus ventral hernia repair. A 78-year-old man, who had undergone robot-assisted radical prostatectomy 10 months earlier, presented with an incisional hernia of European Hernia Society Classification M3W2, length 4 cm, width 5 cm with rectus diastasis. A right single-docking robotic-assisted transabdominal retrorectus repair was performed using a 21 by 14 cm self-gripping mesh and anterior wall reconstruction was done by 0 barbed nonabsorbable running suture. There were no complications and recurrence observed during a 7 months postoperative period. Single-docking robotic-assisted transabdominal retrorectus repair was considered a good option for midline moderate-size incisional hernias from the point of view of the ease of suturing, adequateness of dissection and prevention of bowel injury.     

New protocol to detect coronary spastic angina without fixed stenosis

A new combined test, accelerated exercise following mild hyperventilation (HV), was examined to determine whether it is effective at detecting a positive response in patients with pharmacologically-induced coronary vasospasm and near normal coronary arteries. Fifty-eight consecutive patients who underwent both triple non-invasive spasm provocation tests and diagnostic coronary angiography were enrolled. They all had pharmacologically-induced coronary vasospasms and no significant organic stenosis. In these patients, an HV test was performed first, followed by a treadmill exercise test (TET), and finally the new combined test under no medication within 3 days. Of the 58 patients, positive responses were observed in 9 patients to the HV, in 15 to the TET, and in 35 to the newly combined test. The remaining 21 patients had negative responses although the triple sequential tests were perfomed. Thus, the sensitivities of the HV test, TET, and newly combined test were 16% (9/58), 26% (15/58), and 63% (35/56), respectively. Forty-six subjects with near normal coronary arteries and no ACh-provoked spasm served as controls. None of these subjects had positive responses to any of these three tests, and thus their specificity was all 100%. No serious or irreversible complications were seen in this study. We recommend this newly-combined protocol for the induction of coronary artery spasm in patients with vasospastic angina pectoris and without significant stenosis as a diagnostic tool.     

Noc2 is essential in normal regulation of exocytosis in endocrine and exocrine cells

Rab3 is a subfamily of the small GTP-binding protein Rab family and plays an important role in exocytosis. Several potential effectors of Rab3, including rabphilin3 and Rims (Rim1 and Rim2), have been isolated and characterized. Noc2 was identified originally in endocrine pancreas as a molecule homologous to rabphilin3, but its role in exocytosis is unclear. To clarify the physiological function of Noc2 directly, we have generated Noc2 knockout (Noc2(-/-)) mice. Glucose intolerance with impaired insulin secretion was induced in vivo by acute stress in Noc2(-/-) mice, but not in wild-type (Noc2(+/+)) mice. Ca(2+)-triggered insulin secretion from pancreatic isles of Noc2(-/-) mice was markedly impaired, but was completely restored by treatment with pertussis toxin, which inhibits inhibitory G protein Gi/o signaling. In addition, the inhibitory effect of clonidine, an alpha(2)-adrenoreceptor agonist, on insulin secretion was significantly greater in Noc2(-/-) islets than in Noc2(+/+) islets. Impaired Ca(2+)-triggered insulin secretion was rescued by adenovirus gene transfer of wild-type Noc2 but not by that of mutant Noc2, which does not bind to Rab3. Accordingly, Noc2 positively regulates insulin secretion from endocrine pancreas by inhibiting Gi/o signaling, and the interaction of Noc2 and Rab3 is required for the effect. Interestingly, we also found a marked accumulation of secretory granules in various exocrine cells of Noc2(-/-) mice, especially in exocrine pancreas with no amylase response to stimuli. Thus, Noc2, a critical effector of Rab3, is essential in normal regulation of exocytosis in both endocrine and exocrine cells.     

Fc-rosette inhibition by hypocomplementaemic systemic lupus erythematosus sera

Morito, T., Tanimoto, K., Hashimoto, Y., Horiuchi, Y., and Juji, T. (1976).Annals of the Rheumatic Diseases, 35, 415-421. Fc-rosette inhibition by hypocomplementaemic systemic lupus erythematosus sera. Human red cells sensitized with one of the Rh antisera (Ripley) form rosettes (Fc-rosette) with human B lymphocytes and the rosettes are well inhibited by aggregated human IgG. Since sera of hypocomplementaemic patients with systemic lupus erythematosus (SLE) have frequently been reported to contain immune complexes, they were used for the inhibition of Fc-rosette formation in this study.

The results of Fc-rosette inhibition rates of the sera were inversely correlated with the serum CH₅₀ levels. When the sera were separated into top, middle, and bottom fractions by ultracentrifugation, the bottom fractions showed more effective inhibitions than the others. Similarly, the strongest inhibition was found in the void volume of the serum separated by Sephadex G200 gel filtration. Reduction and alkylation of IgG resulted in the loss of reactivity with Fc receptor of B lymphocytes, and the rosette inhibiting activities of the SLE sera were markedly reduced after reduction and alkylation. Some of anti-HLA sera were inhibitory for the Fc-rosette formation, while the tested sera did not contain anti-HLA activity assessed by the microcytotoxicity test. These results indicated that circulating immune complexes contained in the sera inhibit the rosette formation, and that the Fc-rosette inhibition test is a simple and relatively sensitive method for the detection of circulating immune complexes.

Antinuclear antibody activities of the sera were tested by the indirect immunofluorescent method; however, clear correlations were not obtained between Fc-rosette inhibition rates and staining patterns of antinuclear antibodies. On the other hand, the positive groups of LE-test exhibited slightly greater inhibition rates of the rosette than the negative groups.

     

Effectiveness of combined anticoagulant therapy for extending portal vein thrombosis in Crohn's disease

PURPOSE: Portal vein thrombosis is a rare complication of Crohn's disease, and its precise cause and appropriate treatment are not known. We describe a patient with extending portal vein thrombosis in Crohn's disease who was successfully treated with combined anticoagulant therapy. METHOD: Urokinase and tissue plasminogen activator were administered from a catheter inserted into the superior mesenteric artery, and heparin and a serine protease inhibitor also were given intravenously. RESULTS: On admission, thromboembolic occlusion was observed throughout the entire portal venous system in association with massive ascites and remarkable intestinal edema. After administration of combined anticoagulant therapy, thrombus rapidly decreased in size, and color Doppler ultrasonography showed a gradual increase in portal venous flow. The patient had no recurrence of symptoms while receiving warfarin after resolution of thrombus. CONCLUSION: This case report suggests that combined anticoagulant therapy is effective for patients with severe portal vein thrombosis in Crohn's disease and that color Doppler ultrasonography is useful for evaluation of portal venous flow.     

Results from pelvic exenteration for locally advanced colorectal cancer with lymph node metastases

PURPOSE: We examined the survival benefit of pelvic exenteration for locally advanced colorectal cancer with lymph node metastases, because this issue remains controversial. METHODS: Medical records of 50 patients who underwent curative pelvic exenteration for colorectal cancer were reviewed retrospectively. Nodal metastases were examined by the clearing method in 29 patients and by the conventional manual method in 21 patients. RESULTS: Invasion to contiguous pelvic organs was present in 40 patients (80 percent) and absent in 10 patients (20 percent). Node metastases were present in 33 patients (66 percent). Operative morbidity and mortality rates were 22 percent (11 patients) and 6 percent (3 patients), respectively. Respective five-year survival rates were 60 and 80 percent in the groups with and without organ invasion (no significant difference). Five-year survival rates in patients with nodal metastases was 54.6 percent but was significantly higher, 82.4 percent, in patients without nodal metastases. Five-year survival in 28 patients with both organ invasion and nodal metastases was 53.6 percent. CONCLUSIONS: Long-term survival was afforded by pelvic exenteration for locally advanced colorectal cancer with nodal metastases.