Cytologic features of central giant-cell granuloma of the jaw

In this present series, we studied in detail the cytologic features of five histopathologically verified cases of central giant-cell granuloma (CGCG). All the patients in this series were female, with an age range of 11-60 years. There were three cases with involvement of the lower jaw and two cases had upper jaw involvement. Cytology smears showed dispersed single cells in the background. Nuclei of the individual cells were round to ovoid with fine chromatin and inconspicuous nucleoli. The cytoplasm of these cells was moderate in amount with indistinct cell borders. Many randomly scattered multinucleated giant cells with 10-20 nuclei were present in the background. Combination of clinical features, radiologic pictures, and cytologic features may be helpful for diagnosis of CGCG on fine-needle aspiration cytology.     

Tissue zinc levels in precancerous tissue in the gastrointestinal tract of azoxymethane (AOM)-treated rats

Alterations in tissue zinc levels have been documented in patients with gastrointestinal tract malignancies and more frequently, in those with colonic cancer. However, the precise role of tissue zinc in carcinogenesis is not well elucidated. This study, using a well-established colon cancer model in rats, was designed to investigate the relationship of tissue zinc to the carcinogenic process. The aim was to examine tissue zinc levels in the preneoplastic tissues and to study the changes that occur during transition of mucosa from normal to preneoplastic state. Six-week old rats were given a single dose subcutaneous injection of azoxymethane (AOM) (30mg/kg body weight) and sacrificed after 1, 2, 5, and 9 months of the treatment. Plasma zinc levels showed a significant decrease (p<0.05) at 9 months compared with controls. Tissue zinc levels showed a significant decrease in the large intestine at 1 and 2 months (p<0.05) and at 5 and 9 months (p<0.01), in the small intestine at 2, 5, and 9 months (p<0.05), and in the stomach at 5 and 9 months (p<0.05). The maximum percent decrease (45%) in tissue zinc was observed in the large intestine at 9 months. Tissue copper zinc super oxide dismutase (CuZnSOD) activity was assessed in the body of the stomach, small intestine, and large intestine and compared with the control group. There was a significant fall in CuZnSOD levels in the small intestine at 9 months (p<0.05) and in the large intestine at 5 and 9 months (p<0.01). Two of these six rats showed histological evidence of precancerous lesions in the mucosa of the colon. This study suggests that the decrease in plasma zinc, tissue zinc and activity of CuZnSOD is associated with development of preneoplastic lesions in the colonic mucosa.     

大肠腺瘤三维结构的临床病理研究

我们应用三维结构（３－Ｄ）再构成计算机系统，以０．２ｍｍ间隔连续切片，ＨＥ染色，对５０例经纤维结肠镜切除的大肠腺瘤各种异型上皮的体积及分布规律进行研究。其中癌变１７例（３４％），其平均体积是单纯腺瘤的３．４倍。腺瘤体积越大，其癌变率越高，但体积较小的亚有蒂型腺瘤也有很高癌变率（２５％）。研究结果表明腺瘤体积大小与平均异型度无相关关系。用常规方法切片，仅检出１４例有癌变，漏诊率１８％。为提高腺瘤癌变检出率，至少应以０．６ｍｍ间隔连续切片。此种方法对准确判定断端有无癌浸润也有重要意义。     

Aberrant retinal projections to midbrain targets mediate spared visual orienting function in hamsters with neonatal lesions of superior colliculus

Summary Rodents, cats, and most nonmammalian vertebrates with bilateral tectal deafferentation or ablation in adulthood are extremely deficient at orienting to visual stimuli; yet animals with neonatal lesions of superficial layers of the superior colliculus (SC) show partial sparing of this response, particularly for targets in the central visual field. In this study, we sought to determine whether these spared orienting abilities are mediated by aberrant retinal projections to the remaining intermediate layers of the SC, or whether visual cortex (VC) mechanisms or alternative behavioral strategies are responsible. Neonatal golden hamsters received either bilateral heat lesions of the SC (rlSC), or a heat lesion of the right SC and enucleation of the right eye (rSCrE). This latter procedure causes axons from the left eye to recross the tectal midline and terminate in the wrong (left) SC (Schneider 1973). As adults, both groups of hamsters were extremely deficient in visually guided approach to stationary targets, although rlSC-lesioned hamsters showed some sparing for central field targets and rSCrE-lesioned hamsters often made wrong-direction turns for targets in the left peripheral field. We then subjected both groups of neonatally lesioned hamsters to bilateral aspiration lesions of the VC. Retesting showed no change in visual orienting behavior as a result of the cortical lesions. Labeling of the optic tract with horseradish peroxidase (HRP) revealed abundant aberrant retinal projections to remaining intermediate layers of the SC and thalamic nucleus lateralis posterior (LP), as well as supernormal innervation of pretectal nuclei, the dorsal terminal nucleus of the accessory optic tract, and the ventral nucleus of the lateral geniculate body (LGv). We conclude that the spared visual orienting capabilities of hamsters with rlSC and rSCrE lesions are mediated by the aberrant midbrain projections, and that cortical mechanisms are not involved in spared visual orienting functions following these neonatal lesions.     

Inhibitory effect of DS-4574, a peptidoleukotriene antagonist with mast cell stabilizing action,on compound 48/80-induced gastric mucosal lesions in rats

We evaluated the inhibitory effect of DS-4574, a peptidoleukotriene antagonist with mast cell stabilizing action, on rat gastric mucosal lesions induced by compound 48/80 (C48/80: a mast cell degranulator), in comparison with those of disodium cromoglycate (DSCG: a mast cell stabilizer), LY171883 (a peptidoleukotriene antagonist) and cimetidine (a histamine H₂ receptor antagonist). Subcutaneous administration of C48/80 (1 mg/kg) once daily for four consecutive days produced extensive gastric lesions in the fundic mucosa. DS-4574 (20, 50 and 100 mg/kg/day, oral) and DSCG (200 mg/kg/day, intraperitoneal) treatment markedly inhibited formation of these mucosal lesions, but LY171883 (100 and 200 mg/kg/day, oral) and cimetidine (400 mg/kg/day, oral) treatment did not. Moreover, DS-4574 and DSCG significantly suppressed both hyperhistaminemia and histamine release from rat peritoneal mast cells induced by C48/80. These results indicate that the inhibitory effect of DS-4574 on gastric lesions induced by C48/80 may be related to its mast cell stabilizing action, but to neither its antisecretory nor its peptidoleukotriene antagonistic activity.     

Rostral midbrain lesions and copulatory behavior in male rats

Discrete electrolytic lesions were placed in the mesencephalic dorsal noradrenergic (DNE) bundle of 22 male Sprague-Dawley rats, and sham operations were performed on 14 control animals. Eight components of copulatory behavior were compared in 2 preoperative and 2 postoperative heterosexual mating tests. A significant postlesion decrease in the postejaculatory interval (PEI), number of intromissions, number of incomplete mounts and the ejaculation latency from the first intromission (ELI) occurred. Norepinephrine levels were significantly reduced in the hippocampus, amygdala and hypothalamus, but not in the preoptic area. The only statistically significant correlations between NE concentrations and behavior in the lesioned animals were negative (hippocampal NE with PEI and ELI). The results support the hypothesis that rostral midbrain lesions disinhibit some components of male rodent copulatory behavior, but suggest that a system or systems other than the DNE bundle may be responsible for this disinhibition.     

Immunohistochemical analysis of 14-3-3 sigma and related proteins in hyperplastic and neoplastic breast lesions, with particular reference to early carcinogenesis

In order to confirm the role of 14-3-3 sigma (sigma) as a tumor suppressor in breast carcinogenesis, we have studied the expression of 14-3-3sigma immunohistochemically in usual ductal hyperplasia (UDH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) breast lesions. Immunostaining for estrogen receptor alpha (ERalpha), p53 and estrogen-responsive RING finger protein (Efp) was also carried out. Immunohistochemically, expression of 14-3-3sigma was seen in 92% UDH lesions and gradually decreased from 65% in DCIS to 23% in IDC. The expression of ERalpha decreased gradually from UDH to DCIS to IDC, while p53 showed an inverse staining pattern to that of ERalpha. The expression of Efp showed no significant difference among the three breast lesions. Hence, the present immunohistochemical study confirmed 14-3-3sigma as a tumor suppressor in breast carcinogenesis. A similar immunohistochemical analysis was then carried out on columnar cell hyperplasia with atypia (CCHA), in which the expression pattern of tumor suppressor 14-3-3sigma, ERalpha and p53 suggested that it might be possible that CCHA is a precancerous lesion.     

Nucleus basalis lesions in neonate rats induce a selective cortical cholinergic hypofunction and cognitive deficits during adulthood

Summary Ibotenic acid was infused into the nucleus basalis magnocellularis (nBM) of 2-day old rats to eliminate immature cholinergic neurons before they develop functional synaptic connections in the neocortex. For bilaterally lesioned neonates, cognitive testing was initiated 2 months after lesioning and animals were sacrificed at 8 or 12 months of age. Lesioned animals exhibited a marked deficit in the retention of passive avoidance behavior, as well as in the acquisition of 2-way active avoidance behavior. Lesioned animals also made significantly more alternation errors than control animals in the Lashley III spatial maze and showed severe impairments in general learning, reference memory and working memory during 17-arm radial maze testing. For all 4 tasks, neonatally lesioned animals did not show any recovery to the performance level of control animals. Histological analysis of the subcortex from lesioned animals during adulthood revealed: (1) a substantial reduction in acetylcholinesterase-positive cells (presumably cholinergic) within the nucleus basalis, (2) decreased acetylcholinesterase staining in neocortex and (3) a gliosis essentially restricted to the globus pallidus. Surrounding brain regions were apparently not damaged as a direct result of excitotoxin infusion. Neurochemically, neonate nBM lesioning produced a long term cholinergic hypofunction as evidenced by significant reductions of 25% and 18% in frontal cortex chorine acetyltransferase (CAT) activity at 12 and 8 months of age, respectively. By contrast, prefrontal cortical concentrations of biogenic amines and their metabolites were unaffected, thus indicating a degree of neurochemical specificity for these neonatal nBM lesions. The persistant cortical cholinergic hypofunction in lesioned animals may be related to the long term deficits in learning/memory abilities that were also observed. It is suggested that neonatal nBM lesioning could provide a useful animal model for elucidating the plasticity of the developing brain after cortical anervation.     

Extinction responding by septal and normal rats following acquisition under four schedules of reinforcement

Extinction responding of animals with septal lesions was compared to that of normal animals following acquisition training under either DRL, FI, VI or FR reinforcement schedules (Part 1). During both acquisition and extinction, septals bar pressed more than normals. However, regardless of response levels, a given schedule changed behavior in the same direction for both septals and normals. Thus, if a given schedule led to a decrease in bar pressing by normals, it also led to a decrease by septals, although the absolute level of responding at which this occurred might be different for the two groups. Similarly, if a schedule led to an increase in responding by normals, it also led to an increase by septals. In Part 2 of the experiment operant levels of septals were not found to be different from those of normals, and noncontingent food delivery generated no more nor less bar pressing in septals than in normals. It was proposed that the septal area may be of importance in the initiation of behavior which competes with the required or reinforced response.