Prospective Evaluation of Contrast-Enhanced Computed Tomography for the Detection of Colonic Diverticular Bleeding

Background and Aims

To prospectively evaluate the role of contrast-enhanced computed tomography (CE-CT) in the detection of colonic diverticular bleeding (CDB).

Patients and Methods

Consecutive patients who presented with hematochezia and were clinically suspected of CDB were prospectively enrolled. Those who could undergo both CE-CT and total colonoscopy, and who were finally diagnosed as CDB, were included in the analysis.

Results

Fifty-two cases were finally included in the analysis. The detection rate of CDB by CT was 15.4 % (8/52). Univariate analysis showed that the interval from the latest episode of hematochezia to the performance of CT and the presence of a past history of CDB were contributing factors for detection. The interval was 1.6 ± 4.6 h (mean ± SD) in patients detected by CT, and 3.4 ± 3.2 h in those without detection. The detection rate of CDB by total colonoscopy was 38.5 % (20/52). The overall detection rate was 46.2 % (24/52), which was superior to what CT or colonoscopy alone achieved.

Conclusions

CE-CT may play a complementary role to colonoscopy in patients with suspected CDB, but is not recommended for all cases due to its low detection rate. Patients who can be examined within 2 h of last hematochezia would be candidates for urgent CT.     

Determination of the Optimal Cell-Penetrating Peptide Sequence for Intestinal Insulin Delivery Based on Molecular Orbital Analysis with Self-Organizing Maps

Our recent work has shown that the intestinal absorption of insulin can be improved significantly by coadministration of cell-penetrating peptides (CPPs), especially penetratin. However, a relatively high dose of penetratin is required to adequately stimulate the intestinal absorption of insulin. Therefore, in this study, we sought to determine the CPP that most effectively enhanced intestinal insulin absorption. An in situ loop absorption study using 26 penetratin analogues suggested that the chain length, hydrophobicity, and amphipathicity of the CPPs, as well as their basicity, contribute to their absorption-enhancing efficiency. Moreover, a molecular orbital method with self-organizing maps (SOMs) classification suggested that multiple factors, including the molecular weight, basicity, the lowest unoccupied molecular orbital energy, absolute hardness, and chemical potential of CPPs, are associated with their effects on intestinal insulin absorption. Furthermore, the new CPPs proposed by SOM clustering had a marked capacity to interact with insulin, and their ability to enhance insulin absorption was much stronger than that of the original penetratin. Therefore, the peptide sequence that optimally enhances intestinal insulin absorption could be defined by SOM with the molecular orbital method, and our present work emphasizes the utility of such methodologies in the development of effective drug delivery systems. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:469–479, 2013     

Calcium antagonist flunarizine hydrochloride affects striatal D2 dopamine receptors in the young adult and aged rat brain

The calcium (Ca) antagonist flunarizine hydrochloride (FNZ) has been reported to induce parkinsonism, especially in the elderly. The effects of FNZ on dopamine receptors in rat striatal membranes, especially in aged rats, were studied using radiolabeled receptor assay. Similar displacing potencies in [(3)H]spiperone bindings were exhibited for FNZ and the Ca antagonists verapamil and nicardipine. FNZ was found to directly and competitively effect D2 receptors (D2-Rs) as an antagonist, without effecting D1 receptors. Furthermore, the washing of preoccupied membranes revealed that FNZ has a long-acting potent effect on D2-Rs. The comparative study of FNZ and sulpiride in young-adult and aged rats showed that the effect of FNZ on D2-Rs was more marked in aged rats. These results might be related to FNZ-induced parkinsonism and its high incidence in the elderly.     

Helicobacter pylori-infected Japanese monkeys

Conclusion It is possible to establish persistentH. pylori infection in the gastric mucosa of Japanese monkeys and create acute and chronic gastritis similar to that found in humans; persistent infection causes atrophic changes in the gastric mucosa. Japanese monkeys, which age approximately flve times faster than humans, provide a valuable model for investigating the long-term effects ofH. pylori infection on the gastric mucosa and for the study of stages in the development of gastric cancer. H. pylori produces gastritis resulting in both local inflammation and a systemic immune response. Genes have been isolated that code for cytotoxic proteins such as CagA, VacA, and for heat-shock protein. A number of points remain unresolved concerning the pathology ofH. pylori infection, known to be closely related to the recurrence of peptic ulcers. Routes of infection are fecaloral and oral-oral, and humans can be infected from pets.⁵³ Gastroendoscopy can be a source of nosocomial infections. The natural habitat ofH. pylori in humans is limited almost exclusively to the surface layer of the gastric mucosa; it is rarely found in other locations. In the future, we should develop chemotherapeutic methods for curingH. pylori infections and a vaccine for their prevention. The present study was conducted in accordance with Oita Medical University guidelines for animal experimentation.     

IgE-secreting cells in the thymus: correlation with induction of tolerance to IgE.

We have shown previously that normal mice become tolerant to endogenous IgE when they are approximately 2 weeks old and that this corresponds closely with the initial appearance of IgE in serum. Tolerance evidently is restricted to T cells, since B cells responsive to IgE are present in neonatal and adult mice. The present report shows that IgE-secreting cells can be detected in the thymus between days 7 and 11 after birth and that the onset of tolerance to IgE occurs at the age of 11 days. Similar results were obtained in A/J and (BALB/c x A/J)F1 mice. This suggests that tolerance is induced in the thymus, probably by cells bearing peptide fragments of IgE. The order of appearance of IgE-secreting cells is thymus, spleen, and mesenteric lymph nodes.