Antimutagenic properties of bell and black peppers.

The wing Somatic Mutation And Recombination Test (SMART) in Drosophila melanogaster was used to study the modulating action of bell pepper (Capsicum annuum) and black pepper (Piper nigrum) in combination with the alkylating agent methyl methanesulfonate (MMS) and the promutagen agent ethyl carbamate (EC). Larvae trans-heterozygous for the third chromosome recessive markers multiple wing hairs (mwh) and flare-3 [flr(3)] were fed genotoxins alone or in combination with each of the two spices. Genetic changes induced in somatic cells of the wing's imaginal discs lead to the formation of mutant clones on the wing blade. Our results showed that bell pepper was effective in reducing the mutational events induced by EC and MMS and black pepper was only effective against EC. Pretreatment of 2-day-old larvae with the spices for 24 h followed by a treatment with EC and MMS was only effective in reducing mutations induced by EC. Suppression of metabolic activation or interaction with the active groups of mutagens could be mechanisms by which the spices exert their antimutagenic action.     

Sustained-release theophylline-uniphyllin in nocturnal asthmatics

For a period of six months, we collected 12 cases of nocturnal asthmatics (7 males, 5 females); their ages ranged from 20 to 66 (the average age is 49). We found that administration of Uniphyllin (10 mg/kg) once a day at 6 PM could maintain the blood level of theophylline within therapeutic range at least 12 to 24 hrs. The peak expiratory flow rate of the 6 cases we collected, were significantly improved. The result of pharmokinetic parameters: 1) The average of a single dose (12 cases) is AUC (ug. hr/ml) 275.1 +/- 62. k; Kel (hr-1) 0.068 +/- 0.019; Ka (hr-1) 0.33 +/- 0.07); Tmax (hr) 6.3 +/- 1.4; T 1/2 (hr) 11.2 +/- 4.4; Clearance/F (ml/kg/hr) 37.9 +/- 9.0.2). The average of steady state (12 cases) is Css (mg/L) 5. 7 +/- 2.6; Cmax-Cmin (mg/L) 10.09 +/- 1.46.3). The average of relative bioavailability (3 cases) is 82%, 83%, 102%. However, the extent of absorption data is available for only 3 subjects. There are too few subjects to draw any meaningful conclusions about this relative bioavailability. Four cases show slight symptoms, including 1 case of dizziness, 2 cases of nausea, and 1 case gaseousness. It is suggested that the drug be administered at about 6-8 PM to coincide peak levels in the early morning in nocturnal asthmatics.     

Aging reverts to juvenile conditions the synaptic connectivity of cerebral cortical pyramidal shafts.

Quantitative analysis of the total number and distribution of dendritic spines along the apical shafts of layer V cerebral cortical pyramids has been performed on aging rats (90-120 to 1,135 days old) and on rats during the period of early and late development (10-80 days). As expected from previous work, present results show that the total number of dendritic spines along the shafts increase from 10 to 80 days, after which it starts to gradually decrease until the last age studied (1,135 days). The quantitative analysis of the effect of aging on the relative decrease of dendritic spines shows that this decrease starts being homogeneous along the whole length of the apical shafts and that from a certain age onwards, estimated according to present results in 400 days, this effect is significantly more pronounced in layers IV and III-II than in deep layers. Furthermore, the comparison made between the distribution of dendritic spines along the apical shafts of pyramidal neurons of old and young animals has shown that aging produces a regression of this distribution to juvenile conditions.     

The role of the posterior cricoarytenoid muscle in phonation: an electromyographic investigation in dogs

The activity of the posterior cricoarytenoid muscle during respiration has been well investigated electromyographically. Its activity during phonation, however, has not been studied systematically. We, therefore, focused our attention on the phonatory activity of the posterior cricoarytenoid muscle to confirm whether it also contracts during phonation, as has been reported by some researchers. In our series of 12 adult dogs, the posterior cricoarytenoid was active in 11 dogs and inactive in one dog during phonation. Our present study also showed that the posterior cricoarytenoid activity was stronger for phonation than for inspiration in 6, stronger for inspiration than for phonation in 3, and the same for phonation and inspiration in 2 dogs. The results obtained from the present electromyographic evaluation demonstrated that the posterior cricoarytenoid is activated during phonation. The authors believe that the posterior cricoarytenoid muscle has phonatory function and that the phonatory effect of this muscle on the vocal cord may play an important role in precise glottis control.     

Experimental study of the efficacy of the endoluminal prosthesis in colonic anastomoses

Colorectal surgery is still associated with a significant morbidity and mortality rate, mostly related to suture failure. We have carried out a randomized experimental study in dogs on colonic anastomoses exposed to a number of anastomotic risk situations. A total of 42 dogs was used. They were divided into three study groups (control, occlusion and diverticulitis), with and without an endoluminal tube. The aim was to assess the efficacy of the endoluminal prosthesis using clinical and radiological assessment of anastomotic healing. Pre- and post-anastomotic intraluminal pressures were also measured to determine whether these might be a factor in suture failure. There were significant differences in suture failure in animals in which the endoluminal tube was used. Mean duration of placement was 10.5 days. In the colon healing study, no significant differences were found between the groups in the pathological examination or in the assay of hydroxyproline content. The presence of the endoluminal tube may increase the maximum pressure applied on the colon wall. No significant differences were found in the intracolonic pressure differentials between the different groups or after the inclusion of the endoluminal prosthesis. The results obtained establish the efficacy of the endoluminal prosthesis in protecting the colonic anastomosis, and could be a valuable technique in colonic anastomoses with a high risk of suture dehiscence.     

Neuroradiological features of intracranial and intraorbital meningeal haemangiopericytomas

The neuroradiological features of six intracranial and one intraorbital haemangiopericytomas (HP) are reviewed. CT was performed before and after IV contrast medium in 5 patients. In 2 patients MRI was performed before and after contrast medium; in another, only unenhanced images were obtained. Five patients were studied by selective external and internal carotid artery angiography. Women constituted 5 of the 7 patients, and the mean age was 50.5 years, thus the sex and age distribution did not differ from that of typical meningiomas. Contrary to previous reports, calcification was present in two of the intracranial HP, and bone erosion was clearly seen in one intracranial HP and the orbital lesion. On MRI the tumours showed no differences from angioblastic meningiomas. All 6 intracranial HP were aggressive; all recurred following treatment and extracerebral metastasis occurred in one case.     

双相气道内正压呼吸机在老年慢性阻塞性肺疾病康复期和急性肺水肿患者中的临床应用

应用双相气道内正压呼吸机（ＢｉＰＡＰ）对９例慢性阻塞性肺疾病（ＣＯＰＤ）康复期和呼吸衰竭稳定期进行临床观察发现，治疗后动脉血氧分压与治疗前相比显著升高（Ｐ＜０．０１）；肺活量及用力肺活量轻度升高；１例３次发生急性左心衰、急性肺水肿致急性呼衰患者治疗后，病情很快改善；１例阻塞性夜间睡眠呼吸暂停综合征者应用效果满意。该机应用简便、安全，对心率血压无明显影响，为ＣＯＰＤ康复期、急性左心衰兼肺水肿的治疗提供了新途径。     

Helical computed tomographic angiography in penetrating neck trauma

The purpose of this study was to evaluate the ability of helical computed tomographic angiography (HCTA) to detect vascular injury in penetrating neck trauma. Thirty-five patients (30 gunshot wounds and 5 stab wounds) were studied prospectively with HCTA. Scans were performed with a 5-mm slice thickness at a 1:1 pitch after injection of 90 ml of nonionic contrast medium (30-second delay) at 3 ml/sec. Results were compared with those for angiography (29), surgery (3), ultrasound (2), and local inspection (1). HCTA correctly revealed 19 normal and 10 abnormal studies. In 8 cases, HCTA revealed irregular vessel margins (3), contrast extravasation (2), lack of vascular enhancement (1), and caliber changes (2). In 2 patients, HCTA revealed indirect signs of injury only. In 6 cases, HCTA findings did not correlate with angiography. HCTA detects both direct and indirect signs of vascular injury. Although indirect findings are more sensitive, the direct evaluation of vessels increases the specificity and has a high negative predictive value.     

地学与环境研究

对地学与环境科学研究之间的关系进行了描述,说明学习、掌握了地学的基本知识,才能控制和消除环境污染,改善环境质量,维护经济活动的物质基础与生态平衡.