Studies on isolated smooth muscle cells. IX. Application of papain for isolation of single smooth muscle cells from guinea-pig taenia coli

To prepare single smooth muscle cells from the taenia coli of guinea pig, the application of papain to the enzymatic solution was examined under two conditions: 1) the isolation in a modified Tyrode solution (containing 0.18 mM Ca2+: 0.18 mM Ca2+-Tyrode solution) and 2) the isolation in a high-K+ Tyrode solution (Na+ was replaced by K+, and Ca2+ was not added: high-K+ Tyrode solution). The presence of papain during collagenase digestion reduced contamination of broken cells and cell debris. In the case of the high-K+ Tyrode solution, papain increased the yield of single cells significantly. The cells were contracted in a dose-dependent manner by Ca2+ in the high-K+ Tyrode solution and by carbachol in 0.18 mM Ca2+-Tyrode solution; furthermore, the contractions were antagonized by verapamil and atropine, respectively. Treatment with papain did not affect cell sensitivity to the stimulants. Therefore, our results suggest that the addition of papain is useful for the isolation of single cells to investigate the physiological and pharmacological characteristics of smooth muscle.     

Alveolar hydatid disease of the liver: Brief review and spectrum of adjacent organ invasion

The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease.     

Deprivation of form vision suppresses diurnal cycling of retinal levels of leu-enkephalin

Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth.     

Quantitative assays for C-reactive protein: a review]

C-reactive protein (CRP) is a single most important test among various serological tests which are routinely performed in clinical laboratories. While qualitative assays for CRP are being replaced by quantitative assays, standardization among various laboratories has become an urgent issue. The results of the past three-year surveys conducted by the Japanese Medical Association showed that the coefficients of variation (CV) for CRP assays ranged between 12.6% and 46.9% (1990), although these figures gradually changed for the better. These results clearly indicate that a CRP value obtained in one laboratory cannot be compared directory with that obtained in another laboratory. Every assay for CRP is considered to show good reproducibility, however, which is predicted by the results of within-run precision tests (CV:3.9-7.8%). It is very important to establish standardization for CRP assays but one has to conclude that the path toward this goal is very difficult when one takes into consideration various factors inherent to immunological reactions of macromolecules including possible microheterogeneity of CRP molecules.     

Analysis of discontinuity in visual contours in area 19 of the cat

Previous ablation studies have suggested that area 19 of the cat plays an important role in pattern discrimination. To clarify the functional roles unique to area 19, we studied the receptive-field properties of cells in area 19 and compared them with those of cells in area 17. Recordings were made of anesthetized and immobilized animals. The majority (72%) of the cells in area 17 responded maximally to an elongated bar at a particular orientation, while they responded only weakly or not at all to a small spot (elongation-requiring cells). In contrast, more than half (63%) of the cells in area 19 showed a good response to a nonoriented small stimulus moving in any direction (dot-responsive cells). Two-thirds of the dot-responsive cells in area 19 failed to respond when the moving slit was elongated to more than some length in any orientation. These dot-responsive cells of the "inhibited-by-length" type responded strongly to the end of a long bar, and many of them also responded strongly to a break point in the middle of a long bar. We suggest that these dot-responsive cells of the "inhibited-by-length" type detect discontinuities in contours. Though they are in the minority, elongation-requiring cells constitute a considerable population (37%) in area 19, and dot-responsive and elongation-requiring cells from columnar patches in the same area. We conclude that, in contrast to area 17, whose main role is the decomposition of patterns into oriented contours, area 19 analyzes both orientation and discontinuities, with a strong bias towards the latter.