Development of physical dependence on and tolerance to morphine in rats treated with morphine-admixed food.

1. The development process of physical dependence on and tolerance to morphine has been explored in rats treated with morphine-admixed food (0.5 mg/g of food) during 1 to 7 days. 2. In the morphine-treated animals, body weight loss was observed after the abrupt morphine withdrawal. 3. Intensity and time course of the weight loss were correlated to the morphine treatment. 4. On the other hand, the morphine-treated rats showed abnormal behaviors, such as diarrhea, ptosis, teeth chattering, salivation, body shakes, vocalization, nose bleed, irritability, aggression, lacrimation and writhing upon naloxone injection. 5. Loss of body weight, measured 3 hours after naloxone injection, was also correlated to the duration of morphine treatment. 6. Tolerance to the analgesic effect of morphine developed within one day in rats treated with morphine-admixed food. 7. The drug-admixed food ingestion method has the advantage of rapidly inducing a high degree of physical dependence and tolerance without causing morbidity or lethality in animals. It also eliminates the need for excessive handling of animals.

Histology and tetracycline labeling of a single section of alveolar bone of first molars in the rat.

We observed the histology and tetracycline (TC) labeling in a single frontal section of alveolar bone of upper first molars of adolescent rats. A single injection of TC was administered intraperitonealy in adolescent rats. After three weeks, the upper jaws were immersed rapidly in liquid nitrogen and sectioned. Five micrometer unfixed, undecalcified frozen sections were cut and observed by light and fluorescence microscopy. Frontal sections of the upper first molar area revealed that the structural relationships among the roots, the periodontal ligament and the alveolar bone, and also between the cervical enamel and the attachment epithelium were well preserved. The TC labeling lines in the sections were very clear and distinguished new bone from old bone. The brightness of the lines differed among regions. An analysis of the brightness in the same section suggested a difference in the bone forming activity at the time of injection.

Evaluation of oral antimicrobial agent levels in tooth extraction sites.

OBJECTIVE: The purpose of this study was to evaluate various oral antimicrobial agent levels in tooth extraction sites. STUDY DESIGN: The concentration of dental alveolar blood in extraction wounds after the oral administration of talampicillin (500 mg), cefaclor (500 mg), cefteram pivoxil (200 mg), cefuroxime axetil (250 mg), cefdinir (200 mg), and ofloxacin (100 mg) was determined in 338 patients and was assessed on the basis of its antimicrobial activity against Streptococcus isolated in odontogenic infections. RESULTS: The percentage of patients whose concentrations exceeded the minimum inhibitory concentration for 90% of Streptococcus was 62.5% to 100% for talampicillin at 30 to 360 minutes, 0% to 12.5% for cefaclor at 30 to 360 minutes, 18.2% to 100% for cefteram pivoxil at 30 to 480 minutes, 50% to 100% for cefuroxime axetil at 30 to 480 minutes, 0% to 50% for cefdinir at 16 to 290 minutes, and 0% to 40% for ofloxacin at 30 to 480 minutes. CONCLUSION: These results indicate that talampicillin, cefteram pivoxil, and cefuroxime axetil have minimum inhibitory concentration levels for 90% of Streptococcus in tooth sockets.

A patient whose cerebral aneurysm ruptured soon after an operation to remove a maxillary cyst.

A hypertensive woman complained of a headache soon after an operation to remove a maxillary cyst. A computed tomogram showed evidence of subarachnoid haemorrhage and on angiogram an aneurysm of an anterior cerebral artery. The aneurysm was treated by clipping and the patient recovered.

Pseudoankylosis of the mandible as a result of methyl methacrylate-induced inflammatory cicatricial contracture of the temporal muscle after cranioplasty.

Pseudoankylosis of the mandible after intracranial surgical procedure has been widely reported, and is usually caused by fibrosis of the temporal muscle as a result of injury during the operation. We present an unusual case of mandibular pseudoankylosis as a result of methyl methacrylate-induced aseptic inflammatory cicatricial contracture of the temporal muscle after cranioplasty.

Analysis of DNA from tooth and application to forensic dental medicine.

The DNA extracted from teeth was examined to find out the usefulness in forensic dental medicine. Samples of tooth-derived DNA were digested with a restriction enzyme, electrophosed through agarose gel and subjected to Southern blot hybridization, using a 32P-labeled minisatellite DNA probe "Myo" and a Y chromosome-specific DNA probe. The results indicate that DNA extracted from dental pulp is useful for identification of individuals, paternity testing, and sex determination.

Induction of physical dependence on codeine in the rat by drug-admixed food ingestion.

The developmental process of physical dependence on codeine has been explored in rats treated with codeine-admixed food (0.5 mg/g food) during 1 to 7 days. In rats treated with codeine for more than 2 days, body weight loss was markedly observed after the abrupt codeine withdrawal. The intensity and time course of body weight loss increased according to the duration of codeine treatment. After the codeine withdrawal, behavioral signs such as diarrhea, ptosis and vocalization were observed. In the naloxone-precipitated withdrawal test, rats treated with codeine for 1 day manifested a loss of body weight after naloxone challenge, and the intensity of body weight loss increased according to the duration of codeine treatment. After naloxone injection, the codeine-treated rats showed abnormal behaviors such as diarrhea, ptosis, teeth chattering , salivation, body shakes, vocalization, nose bleed, irritability, lacrimation and writhing. The total score, evaluated by the ranking system for precipitated withdrawal behaviors, was correlated with the duration of codeine treatment. These results suggest that naloxone-precipitated withdrawal signs are powerful in comparison with that after codeine withdrawal, and the weight loss is a common index for quantitative assessment of physical dependence on narcotics in the natural and naloxone-precipitated withdrawal tests. It is concluded that the drug-admixed food ingestion method has the advantage of rapidly inducing a high degree of physical dependence on codeine.

Subdural empyema after tooth extraction in which Capnocytophaga species was isolated.

We describe a patient with meningitis and a subdural empyema arising from an infection after teeth extraction in which Capnocytophaga species was detected. The patient was a 54-y-old man without any underlying diseases. A computerized tomography scan showed a subdural empyema 21 d after the extraction.

A new disposable microvascular double clip.

A new disposable microvascular double clip made of polycarbonate has been designed. In order to investigate whether or not the clip causes vascular damage, experiments were conducted with scanning electron microscopy and light microscopy, using the common carotid arteries of Fischer rats. The study revealed that the new clip did not produce any damage to the arterial wall. The clip has also been used in 30 clinical cases, with generally good results. The new microvascular clip is economical, atraumatic to the vascular wall, and is always in the best condition, because of its disposability. The device is very useful for both laboratory and clinical microvascular surgery.

Incidence of deep fascial space infection after surgical removal of the mandibular third molars.

Nine hundred and ninety-three patients who underwent surgical removal of the mandibular third molars with oral antibiotic prophylaxis were examined to determine the incidence of postoperative deep fascial space infection and its background factors. Postoperative deep fascial space infection was observed in 8 of the patients (0.8%; 4 males and 4 females), and submandibular spaces were involved in all infected patients. Only 1 of these 8 patients was an immune compromised host. Patients aged 30 years or more had a significantly higher incidence of deep fascial space infection than those aged under 30. Five patients had partial bony impactions and 3 had complete bony impactions. However, the incidence of infection according to the molar positions was not significantly different between partial bony impaction and complete bony impaction. The 8 patients had not had pericoronitis preoperatively. The clinical courses of all were favorable after antibiotics were administered intravenously. In conclusion, the incidence of deep fascial space infection after removal of the mandibular third molars was low, at 0.8%. However, it may be desirable to remove the molars, if applicable, at a younger age because of the higher incidence of infection in patients aged over 30. The results of this study also offer information that will be useful as a basis for obtaining informed consent from patients whose mandibular third molars are to be removed.

[Comparison of three methods of inducing physical dependence to morphine in rats using short-term medication].

A comparison of several methods for developing physical dependence to morphine was made. Male Sprague-Dawley rats were treated with morphine-admixed food (drug-admixed food, DAF; 0.5 and 1 mg/g food), morphine slow release emulsion (SRE; 75, 100 and 150 mg/kg) and morphine (75 mg) pellets. In the SRE and pellet methods, the typical signs of morphine toxicity, such as catatonia, exophthalmos and shallow respiratory movements, were observed 15-20 min after the treatment and these signs were maintained for 14-18 hr. In rats treated with SRE and pellets, plasma morphine levels reached a maximum 1 day after the morphine treatment, and subsequently decreased, while plasma morphine levels in rats treated with DAF increased treatment period-dependently. Withdrawal signs precipitated by naloxone (3 mg/kg, sc) in rats treated with DAF, SRE and pellets were characterized by loss of body weight, shaking, vocalization, diarrhea, ptosis, tooth-chattering, nose bleed, salivation and lacrimation. Naloxone-precipitated withdrawal signs reached a maximum 1-2 days after treatment with SRE and pellets, and were correlated with the duration of DAF treatment. Rats treated with DAF, SRE (150 and 225 mg/kg) and pellets for 3 days, manifested loss of body weight, diarrhea etc. after the morphine withdrawal. Maximum body weight loss in each group was 7-10% at 1-2 days after the morphine withdrawal. It was thus, concluded that physical dependence on morphine can be induced rapidly by these three methods. However, the SRE and pellet methods induced morphine toxicity and it was difficult to maintain physical dependence on morphine in these rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapeutic possibilities of long-term roxithromycin treatment for chronic diffuse sclerosing osteomyelitis of the mandible.

The clinical efficacy of long-term roxithromycin treatment was examined objectively in nine patients with chronic diffuse sclerosing osteomyelitis of the mandible. Roxithromycin was administered orally at a dose of 300 mg/day for between 68 days and 66 months. In seven of the nine cases (77.8%), the symptoms disappeared 1-12 months after the start of therapy. Radiography showed that osteolytic changes (evident from 'moth-eaten' appearance of bone) had improved but that osteosclerosis had persisted or become more predominant by the end of therapy. Therefore, the optimum duration of treatment should be decided according to the amelioration of symptoms along with the disappearance of osteolytic findings in radiographs. Diarrhoea and stomach discomfort occurred in one case, and liver dysfunction in another, but these adverse reactions were relatively mild. The mechanism of action of roxithromycin in this study is not yet fully understood, but our results indicate that long-term roxithromycin treatment may be useful for diffuse sclerosing osteomyelitis of the mandible and should be attempted before surgical treatment is considered.