The Effect of Quisqualic Acid-Induced Lesions of the Nucleus Basalis Magnocellularis on Latent Inhibition

Latent inhibition (LI) is a reduction in the rate of acquisition of a Pavlovian conditioned response that results from prior nonreinforced preexposure to a conditioned stimulus (CS). LI has been suggested to reflect the operation of mechanisms involved in stimulus selection for subsequent cognitive processing. The present experiment was conducted to assess the effect of bilateral lesions of the nucleus basalis magnocellularis (NBM) on LI employing a conditioned emotional response paradigm. Bilateral lesions of the NBM were produced by administration of 0.12 M quisqualic acid and resulted in decreased cortical acetylcholinesterase staining, as well as a 40% reduction in cortical choline acetyltransferase activity. Following lever press training, preexposed animals received 40 presentations of a 60-s tone CS. Nonpreexposed animals received no tone presentations. Acquisition of conditioned suppression was then assessed over the course of 4 tone-shock (0.6 mA, 0.5 s) pairings. Control, preexposed animals displayed a retarded rate of acquisition in comparison to nonpreexposed controls, thereby demonstrating that the parameters used in the present experiment produced LI. In contrast, lesioned animals preexposed to the CS acquired conditioned suppression as readily as non-preexposed lesioned animals. However, the acquisition of conditioned suppression in both lesioned groups was found to be similar to that displayed in the preexposed control group. This pattern of results was interpreted as being attributable to a lesion-induced impairment in the ability to maintain stimulus processing, rather than a deficit in the ability to filter a stimulus. Copyright © 1996 Elsevier Science Inc.     

Possible injury to the branches of the peroneal nerve during fibular osteotomies

Conclusions The peroneal nerves and their blood supply are at risk during high tibial osteotomies. Fixation of nerves by fibrous tissues, compression by tendinous arcades of the peroneus longus tendon, and narrow passages for nerves crossing dense fibrous septa are all factors which favor the development of peroneal nerve lesions. Intraoperative soft tissue retraction and pull by retractors may damage nerves and vessels. The muscle branch for the extensor hallucis longus muscle is particularly at risk during the fibular osteotomy since it runs directly on the bone.     

Cervicofacial Rhytidectomy: The Superficial Plane

During the past 20 years, numerous techniques have been described to improve the results of facelifting as well as the duration of its rejuvenating effect. These increasingly aggressive techniques have increased the operating time, the potential morbidity of the operation, and the duration of convalescence. No one can ensure that this evolution in sophistication of rhytidectomy techniques give longer lasting results. Therefore, a simple technique applied under the appropriate indications gives good and predictable results.     

同型半胱氨酸及抗磷脂抗体与深静脉血栓形成和复发关系的研究

目的通过检测深静脉血栓形成（DVT）患者血浆中的同型半胱氨酸（Hey）和抗磷脂抗体（APLA）水平，探讨DVT形成和复发的因素，并寻找DVT复发的预报因子。方法选取2001年1月至2003年4月期间哈尔滨医科大学附属第二医院血管外科收治的60例DVT患者，其中初发组和复发组各30例，另随机选取门诊就诊经证实无DVT的下肢静脉曲张或深静脉功能不全的30例患者作为对照组，同时选取复发DVT的一级亲属组30例。用荧光偏振免疫法测定Hey，用酶联免疫吸附试验（ELISA）检测APLA中的抗心磷脂抗体（AcLA）水平（IgG、IgM型）并测定狼疮抗体（LA）阳性率。结果初发与复发DVT组患者血浆中的Hey和ACLA-IgG及ACLA-IgM水平均高于对照组和复发DVT一级亲属组，差异有统计学意义（P〈0．01）。复发DVT的一级亲属组的血浆中的Hey水平高于对照组（P〈0．05）。各组的LA阳性率差异无统计学意义（P〉0．05）。结论DVT患者血浆中Hey和APLA均升高，Hey和APLA与深静脉血栓形成有密切关系。Hey升高与DVT复发有关，可能是DVT复发的预报因子。     

The effects of peripherald-amphetamine, 4-OH amphetamine, and epinephrine on maintained discharge in the locus coeruleus with reference to the modulation of learning and memory by these substances

d-Amphetamine, 4-OH amphetamine, and epinephrine have been shown in many behavioral studies to facilitate memory when given post-training. The effect of these drugs on the maintained discharge of cells in the locus coeruleus (LC) was investigated using a route of administration (intraperitoneal) and a log-dose range of these drugs comparable to those used in the behavioral experiments.d-Amphetamine profoundly suppressed maintained discharge: an inhibitory effect was observed at every dose (0.1, 1.0, 10.0 mg/kg). In contrast, only the highest dose of 4-OH amphetamine (8.2 mg/kg) inhibited activity in the LC, and this effect was a modest one. Unlike the amphetamines, epinephrine (500 μ/kg) elevated maintained discharge. These results are discussed in the contex of the hypothesized involvement of the LC in the enhancement of memory by these drugs.     

The behavioral neurobiology of learning and memory: A conceptual reorientation

Research on the neurobiology of learning and memory has been guided by two major theories: (i) memory as a psychological process and (ii) memory as a change in synaptic neural connectivity. It is not widely recognised that not only are these theories different but, moreover, they are fundamentally incompatible. Confusion concerning basic concepts in the learning and memory field in mammals has lead to the creation of an extensive but often inconclusive experimental literature. However, one important conclusion suggested by recent work in this field is that experience-dependent changes in neural connectivity occur in many different brain systems. Particular brain structures, such as the hippocampus, do not play any uniquely important role in experience-dependent behavior. Research in learning and memory can be best pursued on the basis of biological studies of animal behavior and a cellular approach to brain function.     

Pathophysiology of idiopathic dystonia: findings from genetic animal models

Dystonia is a common movement disorder which is thought to represent a disease of the basal ganglia. However, the pathogenesis of the idiopathic dystonias, i.e. the neuroanatomic and neurochemical basis, is still a mystery. Research in dystonia is complicated by the existence of various phenotypic and genotypic subtypes of idiopathic dystonia, probably related to heterogeneous dysfunctions.In neurological diseases in which no obvious neuronal degeneration can be found, such as in idiopathic dystonia, the identification of a primary defect is difficult, because of the large number of chemically distinct, but functionally interrelated, neurotransmitter systems in the brain.The variable response to pharmacological agents in patients with idiopathic dystonia supports the notion that the underlying biochemical dysfunctions vary in the subtypes of idiopathic dystonia. Hence, in basic research it is important to clearly define the involved type of dystonia.Animal models of dystonias were described as limited. However, over the last years, there has been considerable progress in the evaluation of animal models for different types of dystonia.Apart from animal models of symptomatic dystonia, genetic animal models with inherited dystonia which occurs in the absence of pathomorphological alterations in brain and spinal cord are described.This review will focus mainly on genetic animal models of different idiopathic dystonias and pathophysiological findings. In particular, in the case of the mutant dystonic (dt) rat, a model of generalized dystonia, and in the case of the genetically dystonic hamster (dt^sz), a model of paroxysmal dystonic choreoathetosis has been used, as these show great promise in contributing to the identification of underlying mechanisms in idiopathic dystonias, although even a proper animal model will probably never be equivalent to a human disease.Several pathophysiological findings from animal models are in line with clinical observations in dystonic patients, indicating abnormalities not only in the basal ganglia and thalamic nuclei, but also in the cerebellum and brainstem. Through clinical studies and neurochemical data several similarities were found in the genetic animal models, although the current data indicates different defects in dystonic animals which is consistent with the notion that dystonia is a heterogenous disorder.Different supraspinal dysfunctions appear to lead to manifestation of dystonic movements and postures. In addition to increasing our understanding of the pathophysiology of idiopathic dystonia, animal models may help to improve therapeutic strategies for this movement disorder.     

局麻下深龋充填对成人牙科畏惧症的影响

目的　探讨局麻下深龋充填对成人牙科畏惧症的影响。方法　采用Corah’s牙科畏惧症评分法 ,筛选出 10 0例需深龋充填的DF成人患者 ,分为实验组与对照组。实验组在局麻下行深龋充填术 ,对照组则为常规的牙科治疗。结果　实验组DF程度明显降低 ,与治疗前以及对照组比较都有显著性差异 (P <0 .0 1)。牙科治疗过程中两组脉搏的变化有显著性差异 (P <0 .0 1)。结论　局麻下行深龋充填术 ,对成人牙科畏惧症有治疗作用     

'What do you notice?' Using posters containing questions and general instructions to guide preschoolers' science and mathematics learning

To increase preschoolers' science and mathematics learning experiences both within and outside the classroom, we developed age-appropriate materials containing general questions and instructions that teachers and parents could use when interacting with their students and children. The questions and instructions were related to a specific science or mathematics skill (e.g., classifying), but were general enough so that they could be applied to a variety of situations. Observations of three classrooms and interviews with the classroom teachers and aides, and the parents of the children in the classrooms suggested that use of these materials was beneficial to the children, teachers, and parents, and resulted in increasing the amount of science and mathematics activities and discussions in two of the classrooms as well as outside the classrooms.