Acquired Dermal Melanocytosis on the Wrist

A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist.     

Natural course of nonreducing disc displacement of the temporomandibular joint: changes in chewing movement and masticatory efficiency.

PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously.     

Influences of angiogenesis and lymphangiogenesis on cancerous invasion in experimentally induced tongue carcinoma

BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.     

Comparative study of G- and D-cell population in the dog stomach

Since somatostatin is a local hormone controlling gastric acid secretion and gastrin release, quantitative histopological distribution of the G-cells and D-cells in the canine whole stomach was investigated by the specific immunoperoxidase staining technique. The G-cells were identified only in the pyloric antrum and the estimated total number of G-cells was 15.5 X 10(6) cells. Most of the D-cells were also found in the pyloric antrum but a few were found scattered diffusely throughout body and fundus of the stomach. The estimated total number of D-cells was 11 X 10(6) cells in the pyloric antrum and 4 X 10(6) cells in the corpus and fundus. The G-/D-cell ratio in the antrum was 1.4:1. The number of G-cells as well as D-cells per unit mucosal surface area was significantly higher on the greater curvature and the proximal part of the antrum than on other areas of the antrum. Thus, the pattern of distribution in G-cells was similar to that of D-cells and there was a highly significant correlation between G- and D-cells per unit mucosal surface area. It would appear that under normal conditions, the number of G- and D-cells in the antrum are in good balance and may play an important role in the control mechanisms related to gastric secretion.     

Radiation and thermal sensitivities of murine tumor (FSa-II) cells recurrent after a heavy irradiation.

Radiation and thermal sensitivities, and cell doubling times (Tds) of C3Hf/Sed mouse FSa-II cells recurring after a heavy irradiation were examined in vitro. Tumors in the leg were irradiated with gamma-rays and observed for late recurrence (in vivo clones), or removed immediately after irradiation and single cell suspensions were plated for colony formation (in vitro clones). Five subclones were selected from original cells in vitro. Survival curves were fitted to the multi-target and linear quadratic models. Surviving fractions at 2 (SF2) and 10 Gy (SF10) irradiations, and those at 30 and 60 min heatings at 44 degrees C (SF30 and SF60), were obtained for each clone. Although, Tds of subclones were slightly longer than those of the parental cells, those of recurrent clones were prolonged substantially with an exception of one cell line. Radiosensitivities of FSa-II parental cells tested in vitro and in vivo were equally radioresistant. Thermal sensitivities of parental cells tested in vitro and in vivo were also identical. All subclones were more radiosensitive compared to the parental cells. The in vitro recurrent clones showed smaller D0 (radiation dose to reduce survival from S to S/e in the exponential portion of survival curve) than the D0 of the parental cells. The SF2 values of four in vitro recurrent clones were greater than that of the parental cells whereas those of two lines were smaller. It was of interest that the in vivo recurrent tumor cells showed a wide variation in the radiation sensitivity. Among 9 tumor cell lines examined, 4 lines were more sensitive and 4 were more resistant compared to the original. FSa-II subclones as well as both in vitro and in vivo recurrent clones showed a wide variation in thermal sensitivity. No consistent changes in the shoulder or in the slope were found. The SF30 or SF60 showed that 5 out of 9 in vivo recurrent clones and 4 out of 9 in vitro clones were more resistant compared to the original cells. No correlation was observed between thermal and radiation sensitivities. The Td was not related with radiation or thermal sensitivity.     

Role of eosinophils in the late asthmatic response

The occurrence of late asthmatic response (LAR) is effectively prevented by corticosteroids, but not all by beta-adrenergic drugs. LAR is considered to be of great clinical and therapeutic importance and to be involved in the progression of bronchial asthma into a severe or even an intractable form. However the exact mechanism of the occurrence of LAR remains obscure in many respects. LAR is believed to be due to type I allergy. In guinea pigs, a positive bronchial inhalation challenge following passive sensitization with allogeneic antibody does not induce LAR or eosinophilic infiltration of lung tissue. This experimental fact led us to surmise that LAR would seem likely to be elicited in passively sensitized animals if pronounced eosinophilic infiltration can be induced concurrently and to conduct an experiment with conjoined inhalation of platelet activating factor (PAF). PAF, which has a chemotactic activity for eosinophils, was administered to passively sensitized animals in attempt to examine a role of eosinophils in LAR. A goodly number of animals developed LAR on additional PAF inhalation. These animals, when compared with those without LAR, showed a significantly larger proportion of eosinophils in BALF (p less than 0.05) with an upward tendency for the proportion of neutrophils. Histologically, there was noted a striking association between LAR and eosinophilic infiltration of the bronchial submucosa. These results suggest that anti-IgE antibody is deeply involved in the elicitation of LAR, stressing the importance of eosinophilic infiltration.