Ascending contraction and descending relaxation in the distal colon of mice lacking interstitial cells of Cajal.

Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum.     

Radical lymph node dissection for cancer of the thoracic esophagus.

OBJECTIVE: The authors documented the localization and frequency of lymphatic spread in squamous cell carcinoma of the thoracic esophagus and evaluated the influence of radical systematic lymph node dissection on patient survival. SUMMARY BACKGROUND DATA: From accumulated surgical experience, it was suggested that some of the patients with lymph nodal involvement from cancer could be cured by its clearance. However, it is only recently that cancer of the esophagus has been evaluated in terms of analyzing lymphatic spread and results of lymphadenectomy. METHODS: Among 1298 patients admitted to the Toranomon Hospital between 1973 and 1993, 913 (70.3%) had resections, including curative and palliative procedures. For this study, 717 patients with TNM RO (resection with no residual tumor at operation in TNM classification) were analyzed. Survival was compared between groups of patients with less extensive thoracoabdominal (two-field) dissections and extensive collothoracoabdominal (three-field) dissections. RESULTS: Comparative study revealed that 5-year survival rate for TNM RO patients after free-field dissection (55.0%) was significantly better (log rank test, p = 0.0013) than the rate after two-field dissection (38.3%). The results were particularly significant in subgroups with stage III and IV (because of nodal factor). Overall 5-year survival rate after all resections was 42.4%. CONCLUSIONS: The role of radical lymph node dissection in cancer of the thoracic esophagus evaluated. Long-term survival was compared between two groups with two- and three-field dissection. It was concluded that survival rate was significantly better in patients with extensive three-field dissection.     

RETRACTED ARTICLE: Effects of dobutamine on the fatigued diaphragm: A comparison with dopamine

We examined the effects of dopamine (DOA) 10 μg·kg⁻¹·min⁻¹ I.V. and dobutamine (DOB) 10 μg·kg⁻¹. min⁻¹ I.V. on the contractility of the fatigued diaphragm in 26 anesthetized, mechanically ventilated dogs. Animals were divided into two groups of 13 each: the DOA and DOB groups. Diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. Diaphragmatic contractility was assessed from changes in transdiaphragmatic pressure (P_di). After diaphragmatic fatigue, P_di at low-frequency (20 Hz) stimulation decreased significantly compared with the prefatigue value (P<0.05), whereas no change in P_di was observed at high-frequency (100 Hz) stimulation. In the fatigued diaphragm, P_di at both stimuli increased with an infusion of either DOA (P<0.05) or DOB (P<0.05). The increase of P_di at 20 Hz stimulation was significantly larger in the DOB group compared with that of the DOA group (P<0.05). In each group, P_di at both stimuli decreased after the cessation of administration. The integrated diaphragmatic electric activity (E_di) in the two groups did not change at any frequency of stimulation throughout the study. We conclude that DOB in comparison with DOA is more effective in improving the contractility of the fatigued diaphragm.     

Expression of cytoplasmic TFF2 is a marker of tumor metastasis and negative prognostic factor in gastric cancer

Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention.     

Production and characterization of a monoclonal antibody (MSN-3) for uterine endometrial and endocervical adenocarcinoma

A monoclonal antibody (MSN-3) was raised using HEC-108 cells derived from poorly differentiated endometrial carcinoma as the immunogen. The immunoglobulin subclass of MSN-3 was IgGr1. The target antigen of MSN-3 was a protein with a molecular weight of 77 kDa, and it was shown to be localized in the cytoplasm. MSN-3 only reacted with 14% of normal proliferative endometrium cells, but it showed a high positivity rate of 66% for endometrial carcinoma. The target antigen of MSN-3 increased as endometrial cells became more malignant, and the possibility of changes in localization was also suggested. Moderately and poorly differentiated endometrial carcinoma showed a high positivity rate for MSN-3. MSN-3 reacted rarely or not at all with normal cervical glandular tissue, but the positivity rate for cervical adenocarcinoma (especially endocervical adenocarcinoma) was a high rate of 59%. The patterns of staining of endocervical adenocarcinoma by MSN-3 included diffuse staining of the whole cytoplasm and not only that near the glandular lumen, as well as staining of the basal cytoplasm. Changes in the localization of the target antigen were clearly associated with carcinogenesis of the cervical glandular cells. The MSN-3-positive rate was high in patients with lymph node metastasis and vascular invasion. Among the staining patterns, the basal and diffuse patterns tended to increase with malignacy. The basal pattern of staining was characteristic of MSN-3, suggesting that it might assist in the diagnosis of cervical adenocarcinoma.     

Expression of the long form of leptin receptor (Ob-Rb) mRNA in the brain of mouse embryos and newborn mice

The long form of the leptin receptor (Ob-Rb) has a cytoplasmic domain which activates the JAK-STAT signal transduction pathway. It is related to appetite and energy expenditure and is expressed in various parts of the brain in adults. In embryos, however, the detailed distribution of Ob-Rb expression sites and the function of the leptin-Ob-Rb system remain unclear, although leptin is detected in human cord plasma and leptin mRNA is detected in mouse embryos. In this study, we investigated the Ob-Rb mRNA expression pattern in the brains of mouse embryos and newborn mice by RT-PCR and in situ hybridization. At embryonic day 10.5 (E10.5), Ob-Rb mRNA was already detected in the brain by RT-PCR. By in situ hybridization, Ob-Rb mRNA was observed in the ventricular zone of the rhombencephalon at E11.5. At E12.5, it was also expressed in the ventricular zone of the telencephalon, mesencephalon and cerebellar primordium. From E14. 5 it was expressed in the cortical plate of the telencephalon and the ventricular zone of the thalamus. At E16.5, it was expressed in the premamillary hypothalamic nucleus, superficial gray matter of the superior colliculus, external germinal and Purkinje cell layers of the cerebellum, and facial nucleus. At E18.5, it was expressed in the arcuate nucleus and ventromedial hypothalamic nucleus. These results suggest that the leptin-Ob-Rb system is related to brain development.