Distribution of NADPH-diaphorase in the central nervous system of an infrared-sensitive snake, Trimeresurus flavoviridis.

The distribution of NADPH-diaphorase (NADPH-d) activity was studied in the central nervous system of an infrared sensitive snake. An inhibitor of nitric oxide synthase, dichloroindophenol (DPIP), was used to distinguish the characteristics of NADPH-d activity. Intensely and weakly NADPH-d-stained neurons and fibers were found in discrete regions throughout the snake brain and cervical spinal cord, such as the olfactory bulb, subcommissural organ, stratum griseum periventriculare, locus coeruleus, dorsal root, dorsal horn, and area X. It was particularly noticed that the trigeminal descending nuclei and reticular formation of the medulla oblongata contained many positive neurons and fibers, but the lateral descending nucleus and nucleus reticularis caloris (infrared sensory nuclei) certainly did not. The positive neurons and fibers were also observed in supraspinal sensory ganglia. DPIP inhibited NADPH-d activity in all regions except for the olfactory/vomeronasal nerve and glomeruli. The results prove for the first time the presence of NADPH-d activity in the ophidian brain and suggest that nitric oxide may be involved in many neural functions, but not in infrared sensory processing.

Temperature-induced changes in the number of vesicles in the free nerve endings of temperature neurons of the snake.

By observing ultrastructural changes under the electron microscope, we illustrated exocytosis and recycling of vesicles in the infrared receptor, a kind of free nerve ending in the pit organ of the crotaline snake, Trimeresurus flavoviridis. While maintaining the snake pit organs at stable temperatures of 15 degrees C, 25 degrees C, and 30 degrees C, we fixed them by perfusion and then processed them for transmission electron microscopy. The largest number of clear and coated vesicles appeared in the terminals at the lowest temperature. The perimeter and area of a terminal were enlarged at 30 degrees C, and "opening waves" on the plasma were prominently found at the highest temperature. We also observed coated vesicles that budded from the plasma membrane in the terminals. The configuration of mitochondria in the terminals was quantitatively different between lower and higher temperatures. The data suggest that exocytosis and endocytosis in these terminals operate in a manner similar to that observed in other cell types.

Selective labeling of [3H]2-deoxy-D-glucose in the snake trigeminal system: basal and infrared-stimulated conditions.

[3H]2-Deoxy-D-glucose (2-DG) and high-resolution autoradiography were employed to investigate labeling patterns of the trigeminal and infrared sensory system in a crotaline snake, the pit viper (Trimeresurus flavoviridis). Following intracardiac injection of 9.25 MBq [3H]2-DG, neurons in the nucleus of the lateral descending trigeminal tract (LTTD), nucleus reticularis caloris (RC), nucleus trigemini mesencephalicus, nucleus trigemini motorius, and trigeminal ganglia were labeled in various degrees after the pit organ had been removed (basal condition). This revealed that a higher rate of glucose utilization occurred in these nuclei than in the common sensory trigeminal nuclei, which lacked labeling entirely. When a pit was stimulated periodically with an infrared stimulus for 45 min, the difference in percentage of labeled cells was ipsilaterally increased by 12.84% in large cells of the LTTD and by 7.55% in the RC, as compared with the contralateral, basal-condition side. These slight changes indicate a small increase of glucose consumption during infrared reception. On the other hand, the small cells in the LTTD showed labeling that did not change with stimulation, suggesting that 2-DG uptake in inhibitory interneurons is relatively constant.

H(+)-ATPase and transport of DOPAC, HVA, and 5-HIAA in monoamine neurons.

The effects of N-methylmaleimide (N-MtM), a vacuolar H(+)-ATPase inhibitor, were evaluated in the putamen of the cat to study the in vivo transport mechanisms of dopamine (DA), 5-hydroxytryptamine (5-HT), and their metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindolacetic acid (5-HIAA), using the brain focal microdialysis technique combined with HPLC. The addition of N-MtM to the perfusate altered invariably the flux of the DOPAC, HVA, and 5-HIAA in a similar pattern, resulting in a decrease of the extracellular levels of such metabolites, its extent being N-MtM concentration dependent, thus indicating that the mechanism(s) of such a decrease is (are) related most likely to decreased transport from the intracellular to the extracellular space as the consequence of the inhibition of the vacuolar H(+)-ATPase of DA and 5-HT neurons by the N-MtM. Furthermore, N-MtM masked the release of DA and 5-HT produced by KCl 120 mmol/l. Indeed, N-MtM increased the extracellular levels of such transmitters to values exceeding 4 to 6 times of those produced by KCl 120 mmol/l alone, which suggests that vacuolar H(+)-ATPase is probably involved also in the retention and/or reuptake process of DA and 5-HT.

[Preliminary experience in salvage treatment for advanced recurrent cancers of the head and neck].

Sixteen patients with far advanced recurrent malignancies (later than Stage IV) of the head and neck were treated with radical salvage surgery combined with radiotherapy, chemotherapy, immunotherapy, laser and/or traditional Chinese medicine. The 2- and 3- year survival rates were 56.3% (9/16) and 37.5% (6/16), which were superior to 6.3% (1/16) and 6.3% (1/16) of similar patients who refused treatment. The authors are of the opinion that aggressive treatment should be attempted for patients with far advanced recurrent cancers of the head and neck.

Tobacco smoking, alcohol consumption, and risk of oral cancer: a case-control study in Beijing, People's Republic of China.

A case-control study of oral cancer was conducted in Beijing, People's Republic of China (PRC). The study was hospital-based and controls were hospital in-patients matched for age and gender with the cases. The response rates for cases and controls were 100 percent and 404 case/control pairs were interviewed. Tobacco smoking and alcohol consumption emerged as independent risk factors for oral cancer. For tobacco smoking, the association was considerably stronger for smokers of pipes than for smokers of cigarettes. For all kinds of tobacco, expressed as cigarette equivalents, the odds ratio (OR) for total pack-years smoked, among males, rose from 1.0 in never-smokers to 3.7 (95 percent confidence interval, 1.8-7.4) in the highest quintile of exposure. Similar results were found for females. The association with tobacco consumption was strong for squamous cell carcinoma but there was no trend in risk associated with tobacco for adenocarcinomas and other histologic types. So few women reported consuming alcohol that this variable could be examined only in males. Risk in the highest category of total lifetime intake of alcohol relative to that in lifetime abstainers was 2.3 (1.1-4.8) with a significant trend in risk with increasing dose (P less than 0.002). The combined effects of tobacco and alcohol appear to be approximately multiplicative in males. The attributable risk of oral cancer for tobacco among tobacco smokers was estimated as 34 percent (45 percent among males and 21 percent among females); for alcohol consumption in males the estimate was 23 percent.

[Prognostic significance of lymph node metastasis in the neck from squamous cell carcinoma in the oral cavity--analysis of 122 cases].

122 patients with squamous cell carcinoma of the oral cavity as treated by radical neck dissection in our hospital are presented. All were followed for more than 5 years. The results indicated that prognosis was better in patients with negative lymph nodes than those with positive nodes, with the former giving a 5 year survival rate twice as high. It was most common for metastasis to develop in the upper deep cervical lymph nodes, the prognosis of which was relatively good after radical surgery. The other prognostic factor was the number of metastatic lymph nodes, more or less than 3. The prognosis was inversely proportional to the number and size of the nodes. The prognosis was poor if the node became fixed, matted and indurated.

[Free vascular pedicle iliac bone graft for reconstruction of mandibular defect with ECT scan monitor].

Thirteen patients with mandibular defects after radical resection of mandibular cancer from Apr. 1984 to May 1987 are reported. There were 9 males and 4 females. The defects were repaired by free vascular pedicle iliac bone grafts. Of these patients, 11 satisfactorily healed as the grafted bone was examined by ECT scan autoradiography. The latter is considered as a reliable objective monitor and a scientific parameter to evaluate the viability of the grafted bone. Wide surgical indication, improved post-operative function, shortened treatment course in one-stage repair are favorable to the patients.

[Radical neck dissection for cancer of the oral cavity].

160 radical neck dissections (RND) were performed on 154 patients with cancer of the oral cavity in which cancer of the tongue predominated. The 3-, 5- and 10-year survival rates of these patients were 62.9%, 58.3% and 36.2%, respectively. Those with advanced lesions or positive lymph nodes had poor prognosis. The lymph nodes commonly involved were the submaxillary and the upper deep cervical nodes but "jumping" metastasis to the lower cervical nodes was observed. Elective radical neck dissection is advised for cancer of the tongue. The Survival rate of the patients treated by preoperative irradiation plus RND is higher than that by surgery alone. Proper management of the postoperative complications and regular follow-up of the patients are suggested.

[Retrospective study on cancer of the base of the tongue].

From Feb. 1962 to Feb. 1982, 54 patients with cancer of the base of tongue were treated in our hospital. There were 44 squamous cell carcinomas and 10 adeno-cystic carcinomas. 46 patients were treated by radiotherapy only, 6 by surgery plus radiotherapy, 1 by surgery and 1 by chemotherapy alone. The 5 year survival rate was 27.1%. The result indicates that radiotherapy alone is poor. The author suggests that for cancer of the base of tongue, a combination of radiotherapy and surgery be used and prospective randomized study be carried out. The defect can be repaired using skin or myocutaneous flaps. In extensive lesions, glossectomy plus laryngectomy should be considered. For the healthy and young patients, the lesions of the base of tongue together with a part of the larynx should be extirpated but for the older man, selective glossectomy is advised.