Guided tissue regeneration in the treatment of furcation defects in mandibular molars

The present investigation was designed to evaluate the regenerative potential of the periodontal tissues in degree III furcation defects at mandibular molars using a treatment procedure based on the principle of guided tissue regeneration. The patient sample included 21 patients, 26-65 years of age, who presented periodontal lesions in the right and left molar regions including "through and through" furcation defects. After an initial examination, each patient was subjected to a series of full-mouth scaling and root planing. 2-3 months later, they were recalled for a baseline examination. The furcation-involved molars were randomly assigned in each patient to either a test or a control treatment procedure. The test procedure included the elevation of muco-periosteal flaps at the buccal and lingual aspects of the molars. Granulation tissue was removed and the exposed root surfaces were debrided and planed. The width and the height of the entrance openings to the furcation defects were assessed. A teflon membrane was adjusted to cover the entrances to the defects (buccal and lingual) and was retained in the manner described by Pontoriero et al. (1988). The flaps were repositioned on the outer surface of the membrane and secured by sutures which were removed after 10 days. Following surgery, the patients were instructed to rinse the mouth twice daily for 4 weeks with chlorhexidine gluconate. The membranes were removed after a healing period of 1-2 months. A surgical procedure identical to the test procedure was performed in the control tooth regions with the exception of the placement of membranes.(ABSTRACT TRUNCATED AT 250 WORDS)     

New feather mite species (Acari,Astigmata) from the Sulphur-crested Cockatoo <Emphasis Type="Italic">Cacatua galerita</Emphasis> and Yellow-crested Cockatoo <Emphasis Type="Italic">C. sulphurea</Emphasis> (Psittaciformes,Cacatuidae)

Two new genera and three new species of feather mites (Astigmata, Pterolichoidea, Analgoidea) are described from two closely related species of cockatoos, Cacatua galerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen. nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualges microdiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on these two species of parrots points to a very close affinity of Cacatua sulphurea and C. galerita and gives additional support for the recent hypothesis of the conspecificity of these birds.     

装潢居室空气中挥发性化学物的遗传毒性研究

目的探讨装潢居室空气中挥发性化合物的遗传毒性.方法采用小鼠骨髓嗜多染性红细胞微核试验和小鼠精子畸形试验检测居室装潢后空气中挥发性化合物的遗传毒性.结果该化合物对小鼠呼吸系统有明显的刺激作用,与阴性对照组比较,高、中、低剂量组的微核率、精子畸形率均有显著差异性.结论居室装潢后室内空气中挥发性化合物具有遗传毒性作用.     

Oxygen Tension Imaging in the Mouse Retina

A newly developed microscope-based imaging system was used to measure the oxygen tension (PO₂) inside the retinal and choroidal vessels of mice and to generate in vivo maps of retinal PO₂. These maps were generated from the phosphorescence lifetimes of an injected palladium–porphyrin compound using a frequency-domain measurement. The system was fully calibrated and used to produce retinal PO₂ maps at different inspiratory oxygen fractions. PO₂ rose accordingly and predictably as inspiratory O₂ was stepped from hypoxic to hyperoxic conditions. Important experimental and acquisition parameters necessary for applying phosphorescence lifetime imaging to the mouse eye were investigated, including camera exposure and intensifier gain settings. Because of a need to limit light exposure to the retina, PO₂ map quality as measured by the coefficient of determination was investigated as a function of signal-to-noise and accumulated excitation energy deposition. With the development of this technology for use in mice, the potential for investigating the oxygen dynamics in genetically engineered mouse models of retinal disease, including diabetic retinopathy, glaucoma, and age-related macular degeneration, is advanced. © 2003 Biomedical Engineering Society. PAC2003: 4266Ew, 8763Lk, 8719Dd     

Effects of local nerve cooling on conduction in vagal fibres shed light upon respiratory reflexes in the rabbit

In ten vagus nerves the effect of local cooling on the compound action potential was studied in the temperature range of 34 to 0 °C in spontaneously breathing, anaesthetized rabbits. The mean temperature at which the myelinated (A) fibres were completely blocked, was 10.2±2.4 °C (mean ± S.D.). In nine nerves, local vagus cooling to 0 °C failed to block all non-myelinated (C) fibres. In one nerve, total blocking occurred at 2.0 °C. We conclude that in the rabbit, the earlier found increase in tonic activity of the diaphragm following lung inflation or deflation during bilateral local vagus cooling to a temperature between 8 and 0 °C is due to afferent impulses in vagal C fibres.     

新等位基因人类白细胞抗原B*4609的发现和确认

目的 鉴定一个人类白细胞抗原(human leukocyte antigen,HLA)新等位基因HLA-B*4609.方法 使用序列特异性寡核苷酸PCR技术进行HLA基因分型,发现反应格局异常的可疑新等位基因,应用分子克隆和DNA双向测序技术测定新等位基因的核苷酸序列,并与已知等位基因进行序列比对分析.结果 检出1个样本HLA-B位点反应格局异常,DNA测序分型结果一个为B*151101,另一个的核苷酸序列与已知的HLA等位基因均不同,该基因序列与同源性最高的HLA-B*460101基因序列相比,在第3外显子区域中527位碱基发生A→T突变,导致176位编码氨基酸由谷氨酸(GAG)变成缬氨酸(GTG).结论 样本中含有HLA-B新等位基因序列.该序列申报后,被世界卫生组织HLA因子命名委员会正式命名为HLA-B*4609.     

New therapies for systemic lupus erythematosus

In the past 40 years, prognosis for patients with systemic lupus erythematosus (SLE) has improved, with 10-year survival now approximately 90%. This is due probably to a combination of earlier disease diagnosis and diagnosis of milder disease, due in part to availability of multiple serological tests for SLE, use of steroids and other immunosuppressive agents, and availability of renal dialysis and transplantation. Despite this, however, the potential for significant morbidity and mortality remains in the group of patients with partially responsive or treatment resistant disease. More recently, advancements in the understanding of molecular mechanisms involved in the pathogenesis of SLE have translated to the development of novel therapies, offering possible alternatives to this patient cohort. Discussion of these pharmacological options and ongoing research forms the basis of this review.     

Distribution of TT virus genomic groups 1-5 in Brazilian blood donors, HBV carriers, and HIV-1-infected patients

Human isolates of the highly prevalent TT virus (TTV) have been classified into five major genomic groups (1-5). The geographical distribution of the groups throughout the world is not well known. Five different PCR assays were developed in an attempt to amplify specifically TTV DNAs of each genomic group. Serum samples collected from 72 Brazilian adults (24 voluntary blood donors, 24 hepatitis B virus (HBV) carriers, and 24 human immunodeficiency virus type 1 (HIV-1)-infected patients) were tested. TTV DNA from at least one genomic group was detected in 11 (46%) blood donors, 13 (54%) HBV carriers, and 24 (100%) HIV-1 patients. All five genomic groups were detected in the three populations, with the exception of group 2 in blood donors. Some samples, negative with all five specific assays, were positive with the commonly used untranslated region (UTR) PCR system. On the other hand, TTV DNA was detected in some samples by using specific assays but not with the UTR PCR. Mixed infections with 2-5 TTV isolates from different groups were detected in 21% blood donors, 29% HBV carriers, and 71% HIV-1 patients. Fifteen PCR products (three obtained with each assay) were sequenced. Most sequences showed high (>86%) homology with those of TTV isolates belonging to their presumed groups. However, three sequences had low homology with all TTV sequences available from the DNA databanks. In conclusion, TTV isolates belonging to all five known genomic groups circulate in Brazil, and the results suggest the existence of new and as yet uncharacterised major genomic groups.     

白松片对慢性应激抑郁模型大鼠行为学及血浆CORT、ACTH的影响

目的：观察白松片对慢性应激抑郁大鼠模型行为学和血浆CORT、ACTH含量的影响。方法：SD雄性大鼠28只随机分为空白对照组、模型对照组、氟西汀对照组及白松片试验组，选用慢性轻度不可预见性应激加孤养造模，观察各组大鼠敞箱实验和液体消耗等行为学指标变化，采用放射免疫方法检测大鼠血浆皮质醇(CORT)和促肾上腺皮质激素(ACTH)含量。结果：慢性应激抑郁大鼠体重增加缓慢，敞箱实验中的水平运动、垂直运动得分、清洁动作次数显著减少，中央格停留时间显著延长；糖水消耗明显下降，纯水消耗显著增多，而且其血浆皮质醇和促肾上腺皮质激素含量增加。氟西汀和白松片均显著改善慢性应激抑郁大鼠模型的行为学和神经内分泌变化。结论：慢性轻度不可预见性应激可使大鼠行为及神经内分泌发生异常改变，引起抑郁状态，白松片对此具有一定拮抗作用。     

前臂后皮神经营养血管远端蒂复合瓣的应用解剖

目的:为前臂后皮神经营养血管远端蒂复合瓣设计提供解剖学基础。方法:30侧动脉灌注红色乳胶成人上肢标本,解剖观测前臂后皮神经营养血管的来源、分支、吻合及其与尺、桡骨膜血管的关系。结果:前臂后皮神经营养血管来自:桡侧副动脉皮支2～6支,外径(0.6±0.3) mm;骨间后动脉皮支6～9支,外径(0.7±0.3) mm;骨间前动脉腕背支皮支3~5支,外径(0.8±0.2) mm;尺、桡动脉腕背支皮支2~6支,外径(0.6±0.1) mm。尺骨中上段骨膜血管来自骨间后动脉的肌骨膜支6～8支,外径0.3～1.0 mm;骨间后动脉桡侧骨皮支与桡骨中段裸区骨膜血管吻合。上述支发出皮支、筋膜支、骨膜支和神经营养血管,形成皮神经干血管链以及深、浅筋膜和骨膜血管网。结论:前臂后皮神经营养血管与肌、骨、皮营养血管同源,其远端蒂复合瓣,旋转轴点在腕关节平面,适宜手背远处的组织缺损修复。