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.     

Characterization of dehydrochlorinated poly(vinylidene chloride) and the shock-compressed material

Dehydrochlorinated poly(vinylidene chloride) proved to be a conjugated polyene-polyene polymer. Shock compression of the polymer formed a large portion of graphite and trace amounts of diamond and of an unknown carbon. The unknown carbon belongs to the hexagonal crystal system and possesses the cell dimension α₀ = 0.338 nm. A comparison with known carbynes was made in terms of the crystalline parameters.     

POSSIBLE PARTICIPATION OF NMDA AND GLYCINE RECEPTORS BUT NOT GABAA RECEPTORS IN ENFLURANE-INDUCED OPISTHOTONUS IN MICE

1. We previously reported that volatile anaesthetics produce incidences of a transient opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABA_A antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P<0.01) reduced both the incidence of EIO and IT in a dose-dependent manner. During the pre-enflurane period DIZ produced incidences (5–40%) of transient seizures in a dose-dependent manner, while KET did not induce them at all. The two GABA_a antagonists had no detectable effect on the EIO. Strychnine significantly enhanced the EIO. These CNS stimulants resulted in a 3–10% incidence of transient seizure and/or opisthotonus during the pre-enflurane period, but there was no correlation between DIZ-induced seizure and EIO. 4. These results suggest that the EIO is mediated by the NMDA and the STR-sensitive glycine receptors, but not the GABA_A receptor. We speculate that DIZ acts on the NMDA-receptor and/or disrupts the balance between the inhibitory and the excitatory systems.     

Long-term follow-up studies in 211 patients with tetralogy of Fallot after corrective surgery over 10 years

A total number of 427 patients with tetralogy of Fallot who underwent corrective surgery between 1960 and March 1990, in whom 211 patients who survived the surgery over 10 years were evaluated for the follow-up studies. Hemodynamic and cardiac function studies were carried out in 101 patients at the mean interval of 15.7 years (ranges 2 to 21 years). Three methods indicated that patients with muscle resection and pulmonary valvulotomy without patch enlargement (NP) had worse results than the groups with RV patch below valve (RP) and with transannular patch (TP). Also, Holter ECG revealed ventricular arrhythmias in patients with NP were more common than the groups with RP and TP. Sixteen patients (13 with NP, 2 with TP and one with RP) were required reoperation for residual ventricular shunt in 13, residual pulmonary stenosis in 11 and tricuspid regurgitation in 2. All of these 16 patients survived operation and obtained excellent clinical status. It is concluded that patients with TOF after corrective surgery should be carefully followed with short term interval to prevent sudden death and postoperative complications.