Tenotomy prevents the functional improvement of a muscle reinnervated with a chronically severed nerve

During the early stages of nerve implantation, we followed the dynamic properties of the lateral gastrocnemius muscle of the rat, reinnervated with an acutely or chronically severed peroneal nerve. The aim of this study was to ascertain whether (1) the better functional recovery of a muscle reinnervated by a chronically severed foreign nerve is present from the onset of reinnervation, and (2) whether such functional improvement is due to the conditioning lesion effect. Our results indicate that better functional recovery is already apparent one week after nerve implantation, and it is due to the conditioning lesion effect, since tenotomy prevents such improvement. The tenotomy effect underlines the fact that some environmental factors concerning the target tissue, and not only the predegenerated nerve, are involved in the conditioning effect. © 1995 Wiley-Liss, Inc.     

保留下齿槽神经的颌骨切除兼植骨术

本文报告保留下齿槽神经血管束的下颌骨部分切除并即刻植骨修复新的手术方法5例.术后颜面部外形基本对称,6个月后对患侧下唇及颏部进行物理及电刺激等手段测试温、触、痛觉,功能恢复满意。     

Ultrastructure of experimental candidial lesions in the rabbit esophagus

Although the esophagus is the most frequent site ofCandida infections in the gastrointestinal tract, and many clinical studies about it have been reported, little attention has been directed toward experimental candidiasis of the esophagus, especially with regard to its ultrastructure. Using transmission electron microscopy, this study was performed to clarify the ultrastructure of experimental lesions, obtained from five New Zealand white male rabbits which were given a suspension ofCandida albicans cells (10⁷/ml) for 13 days. The results showed that the lesions consisted of exfoliating, squamous epithelial cells with mycelial elements ofCandida albicans cells penetrating through them, and that a widened intercellular space between individual cells in the area of candidial invasion seems to be a characteristic finding of candidial infection. A part of this study was presented at the 25th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Matsumoto, September 28–30, 1993.     

Idiopathic scoliosis: biomechanics and biology

For whatever reason, right-left asymmetry has attracted an illogical proportion of research effort. Non-structural scoliosis, for example secondary to a leg length inequality, is indeed a problem of right-left asymmetry, but structural scoliosis is a complex three-dimensional deformity involving all planes. Biomechanical, biological and clinical evidence indicates clearly that the problem is one of front-back asymmetry and not right-left. The importanc of biological factors lies in their ability to bring the spinal column to and beyond its buckling threshold. Thus a taller and more slender spine is more liable to bend and, being stiffer in the sagittal plane, favours movement into other planes. This epitomises the spine of the scoliosis patient who is growing faster with a spinal template similar to other family members allowing idiopathic scoliosis to express itself genetically. It is the opposite condition to idiopathic hyperkyphosis (Scheuermann's disease), but this deformity is rotationally stable, thus remaining in the sagittal plane. The presence of an adjacent area of lordo-scoliosis below the region of hyperkyphosis testifies to the common nature of the pathogenesis of idiopathic scoliosis and Scheuermann's disease. It is the area of compensatory hyperlordosis below the Scheuermann's area that has obligatorily buckled and represents a human model supporting the lordosis theory, as does surgically tethering the back of the young growing human spine, which crankshafts accelerated progression. Similarly the only successful animal model of the formation of idopathic follows creation of a lordotic spinal segment in an otherwise kyphotic spine. For centuries, engineers have recognised that the mechanical behaviour of a column under load is influenced by geometry, as well as by material properties; it is clear that the spinal column also obeys these well-described laws.     

The influence of white matter lesions on neuropsychological functioning in demented and non-demented 85-year-olds

White matter lesions on computed tomography of the head were studied in relation to neuropsychological functioning in subjects from a representative sample of non-demented ( n = 134) and demented ( n = 98) 85-year-olds. Non-demented subjects with white matter lesions ( n = 46) scored significantly lower in tests of verbal ability (Synonyms), spatial ability (Block Design, Clock Test), perceptual speed (Identical forms), secondary memory (Thurstone Picture Memory), basic arithmetic (Coin Test) and the global cognitive screening test Mini-Mental State Examination than non-demented subjects without white matter lesions ( n = 88). Demented subjects with white matter lesions ( n = 67) scored significantly lower in tests of spatial ability (Block Design and Clock Test) and secondary memory (free recall in the MIR memory test, Ten-word memory test I and II) and in the Mini-Mental State Examination than demented subjects without white matter lesions ( n = 31). It is concluded that white matter lesions contribute to cognitive decline in both non-demented and demented elderly subjects.     

CLINICAL OBSERVATION OF 74 REVASCULARIZED OSTEOMYOCUTANEOUS FLAP GRAFTS TO RECONSTRUCT THE MANDIBULAR DEFECTS

Vascularized osteomyocutaneous transplantation using the technique of microvascular anastomosis has shown many advantages. For the purpose of immediate reconstruction of composite defects of the mandible, 74 osteomyocutaneous flaps have been used in the last six years. They included 43 iliac osteomyocutaneous flaps pedicled to the deep circumflex iliac artery, 16 latissimus dorsi osteomyocutaneous flaps pedicled to the thoracodorsal artery and 15 pectoralis major asteomyocutaneous flaps pedicled to the acromiothoracic artery. The survival rate of the former was 90.7% (39/43), and the latter two 71% (22/31). The factors influencing the survivalrate of these osteomyocutaneous flaps have been analyzed; the complications of the recipient and donor sites have been presented; the long term results have been discussed. The authors conclude: mandibular reconstruction by using osteomyocutaneous flap grafts has the advantages of resistance to infection, fast bone healing and survival in a poorly vascularized recipient bed. The iliac osteomyocutaneous flap is better than the other two in survival ability.     

Visualisation of the mandibular canal by different radiographic techniques

6 mandibles were radiographically examined bilaterally to visualise the mandibular canal. 5 imaging techniques were used: periapical radiography, panoramic radiography, hypocycloidal tomography, spiral tomography and computed tomography (CT). Panoramic radiographs were obtained with 2 different X-ray machines. The CT-examinations comprised direct images and standard reconstructions based on axial slices. The specimens were subsequently sectioned for contact radiography. The visibility of the mandibular canal was estimated by 3 observers at special reference points on all radiographs and classified as clearly visible, questionable visibility or not visible. The contact radiographs served as the "gold standard". The inter-observer and the intra-observer agreement were assessed by calculating the overall agreement and the x value. Direct coronal computed tomography, as well as spiral and hypocycloidal tomography, gave better visualisation of the mandibular canal than periapical and panoramic radiography.     

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)     

Intrinsic Organization and Connectivity of Intrastriatal Striatal Transplants in Rats as Revealed by DARPP-32 Immunohistochemistry: Specificity of Connections with the Lesioned Host Brain

Intrastriatal grafts of tissue obtained from the striatal or neocortical primordia of rat fetuses have been studied with respect to their intrinsic organization and connectivity using antibodies to DARPP-32 in combination with acetylcholinesterase (AChE) histochemistry, tyrosine hydroxylase (TH) immunocytochemistry, and anterograde and retrograde axonal tracing techniques. The striatal grafts were characterized by distinct patches of DARPP-32-immunoreactive neurons, which were identical to the densely AChE-positive patches stained in adjacent sections from the same specimens. The non-patch areas possessed only few DARPP-32-positive neurons and contained only sparse AChE-positive fibres. The cortical grafts, by contrast, contained no neurons with clear-cut DARPP-32-positivity and they exhibited a sparse, evenly distributed AChE fibre network, similar to that seen in the non-patch areas of the striatal grafts. The host dopaminergic afferents, as revealed by TH immunostaining, had grown selectively into the DARPP-32-positive patches in the striatal grafts, where they formed a dense terminal network around the DARPP-32-positive cell bodies. The non-patch areas, as well as the cortical grafts, received only sparse TH innervation. By contrast, the host cortical afferents, labelled by Phaseolus vulgaris leucoagglutinin from the host frontal cortex, were seen to extend into both the patch and non-patch areas of the striatal grafts. Transplant neurons projecting into the host brain were labelled by Fluoro-Gold injections into the ipsilateral host globus pallidus. These injections labelled large numbers of medium-sized neurons within the striatal grafts and the vast majority of them (over 85%) were confined to the DARPP-32-positive patches. Similar Fluoro-Gold injections labelled only few graft neurons in the cortical grafts. The results indicate that the striatal grafts are composed of a mixture of striatal and non-striatal tissue, and that the striatal graft compartment selectively establishes afferent and efferent connections with the host nigro-pallidal system. These graft connections demonstrate a remarkable specificity in the formation of graft - host connectivity. The results, moreover, suggest that developmental properties of the grafted striatal primordium are retained and expressed in the implanted cell suspension, and that the neuronal systems of the lesioned adult host brain, at least to some extent, remain responsive to growth regulating mechanisms normally operating during ontogenetic development.     

鼻咽癌旁上皮细胞核DNA含量分析

应用显微分光光度计测定15例鼻咽癌19处癌旁病变的上皮细胞核DNA含量并与浸润癌相比较。中、重度异型增生上皮细胞核DI及超过2.5c细胞的百分数处于单纯增生+轻度异型增生与浸润癌之间,3组DI及超过2.5c细胞的百分数差异显著。中、重度异型增生以非整倍体为主,其细胞核DNA含量组方图相似于浸润癌。从细胞核DNA含量角度来看,中、重度异型增生是重要的癌前病变。