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21.
A. B. Soares P. R. Faria L. A. Magna M. E. P. Correa C. A. de Sousa O. P. Almeida M. L. Cintra 《Journal of oral pathology & medicine》2005,34(6):368-373
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease. 相似文献
22.
Chemically distinct rat olivocochlear neurons. 总被引:6,自引:0,他引:6
We have produced a neurochemical map of the cell bodies of origin of the cochlear efferent terminals in rat by combining glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), or calcitonin gene-related peptide (CGRP) immunocytochemistry with retrograde transport of horseradish peroxidase. The locations of cochlear efferent cell bodies are in general agreement with the medial and lateral systems described by White and Warr (J. Comp. Neurol. 219:203-214, 1983) with some minor modifications. The lateral system consists of at least two pools of chemically distinct neurons located within the lateral superior olive (LSO) ipsilateral to the injected cochlea. One pool immunostains with an antibody to GAD while the other immunostains with antibodies to ChAT and to CGRP. The medial efferent system consists of periolivary neurons that are almost exclusively large and ChAT-positive but CGRP-negative. They are located both ipsilateral and contralateral to the cochlea they project to. There are a few GAD-positive small neurons in the medioventral and rostral periolivary regions that project ipsilaterally, but these may prove tobe ectopic neurons. The ipsilateral lateroventral periolivary region (LVPO) contains some efferent neurons, all of which are ChAT-positive but CGRP-negative. Additional cochlear efferent neurons, some of which are ChAT-positive and others GAD-positive, are present within and immediately dorsal to the fiber capsule surrounding the medial limb, and to a lesser extent the lateral limb, of the ipsilateral LSO. Not all GAD-positive or ChAT-positive olivary cells project to the cochlea. We have complemented the results in the brainstem by demonstrating two immunocytochemically distinct populations of efferent terminals in the cochlea simultaneously, one CGRP-positive and the other GAD-positive. Approximately equal numbers of boutons immunoreactive for both markers are present beneath inner hair cells throughout the entire length of the cochlea. Surprisingly high numbers of GAD-positive and CGRP-positive boutons are also present on outer hair cells, with each class having its spatially and morphologically distinct features. The lack of CGRP-positive periolivary cells that are retrogradely labeled by cochlear injections of HRP suggests that the lateral olivocochlear system sends projections to outer hair cells. Our results raise questions about species differences in the organization of targets of the lateral and medial olivocochlear systems. 相似文献
23.
Abstract Surgical treatment of proximal humeral fractures still remains a challenge. This is primarily due to the fact that sufficient
implant fixation in humeral head fractures is often not achieved due to substantial bone tissue loss with increasing age.
In the last few years the locking plates and locking nails have been introduced into clinical practice with varying results.
The biomechanical studies have focused on locking plate osteosynthesis as well. The following paper focuses on bone quality,
biomechanical studies and biology of proper osteosynthesis and reviews the most recent literature. 相似文献
24.
Masafumi Kumano Hideaki Miyake Isao Hara Junya Furukawa Atsushi Takenaka Masato Fujisawa 《International journal of urology》2007,14(4):336-338
BACKGROUND: The objective of this study was to evaluate the efficacy and safety of first-line high-dose chemotherapy (HDCT) combined with peripheral blood stem cell transplantation (PBSCT) for patients with advanced extragonadal germ cell tumors (EGGCT). METHODS: Six male patients with advanced non-seminomatous EGGCT were treated with HDCT combined with PBSCT following 2-3 cycles of conventional-dose induction chemotherapy. The regimens used for HDCT were carboplatin, etoposide and ifosfamide (ICE) in five patients and ICE plus paclitaxel (T-ICE) in one patient, and that for induction therapy was cisplatin, etoposide and bleomycin (PEB) in all patients. As a rule, HDCT was continuously administered until alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin normalized (beta-HCG). RESULTS: Following 1-6 courses of HDCT (median, 4 courses), beta-HCG and AFP were normalized in all patients, and five and one patient were diagnosed as showing partial remission and stable disease, respectively. Five patients underwent surgical resection of residual tumors after HDCT, yielding necrotic tissue in two, mature teratoma in two, and viable cancer tissue in one, and the surgical margin was negative in all patients. At a median follow-up of 36 months, five patients were alive and disease-free, whereas the remaining one died of disease progression. Although all patients had grade 3 hematological toxicity, there was no treatment-related death by combining PBSCT. CONCLUSIONS: First-line HDCT with PBSCT could be safely administered to patients with advanced EGGCT, and the antitumor effect of this treatment was comparatively favorable. First-line HDCT therefore may represent an attractive option for patients with advanced EGGCT. 相似文献
25.
Tsuneharu Miki Yoichi Mizutani Hideyuki Akaza Seiichiro Ozono Taiji Tsukamoto Toshiro Terachi Katsusuke Naito Norio Nonomura Isao Hara Osamu Yoshida The Japan Blood Cell Transplantation Study Group for Testicular Germ Cell Tumor 《International journal of urology》2007,14(1):54-59
OBJECTIVE: Standard chemotherapy shows relatively low long-term survival in patients with poor-risk testicular germ cell tumor (GCT). First-line high-dose chemotherapy (HD-CT) may improve the result. High-dose carboplatin, etoposide, ifosfamide chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) was investigated as first-line chemotherapy in patients with advanced testicular GCT. METHODS: Fifty-five previously untreated testicular GCT patients with Indiana 'advanced disease' criteria received three cycles of bleomycin, etoposide and cisplatin (BEP) followed by one cycle of HD-CT plus PBSCT, if elevated serum tumor markers were observed after three cycles of the BEP regimen. RESULTS: Thirty patients were treated with BEP alone, because the tumor marker(s) declined to normal range. Twenty-five patients received BEP and HD-CT. One patient died of rhabdomyolysis due to HD-CT. Three and six (13% and 25%) out of 24 patients treated with BEP and HD-CT achieved marker-negative and marker-positive partial responses, respectively. The other patients achieved no change. Fifteen (63%) are alive and 14 (58%) are free of disease at a median follow-up time of 54 months. Severe toxicity included treatment-related death (4%). CONCLUSIONS: HD-CT with peripheral stem cell support can be successfully applied in a multicenter setting. HD-CT demonstrated modest anticancer activity for Japanese patients with advanced testicular GCT and was well tolerated. This regimen might be examined for further investigation in randomized trials in first-line chemotherapy for patients with poor-risk testicular GCT. 相似文献
26.
Torsion of noncircular beams results in warping of each cross section. When noncircular cross sections are constrained to remain plane, the resulting shear stress distribution is different from what Saint Venant torsion (with warping) would predict. This has practical implications to the stress analysis of plated long bones subjected to torsional loadings. Analyses in which warping is not allowed predict incorrect stress fields in the plate and bone and overpredict the amount of stress shielding associated with fracture plate fixation. 相似文献
27.
Prevention of early postmenopausal bone loss using low doses of conjugated estrogens and the non-hormonal,bone-active drug ipriflavone 总被引:2,自引:0,他引:2
Hormone replacement therapy is the optimal therapeutic choice for postmenopausal syndrome. While low doses of estrogens (0.3 mg/day of conjugated estrogens) can counteract neurovegetative menopausal symptoms, higher doses (0.625 mg/day of conjugated estrogens) are required to prevent bone loss in postmenopausal women. Experimental and clinical studies have shown that ipriflavone, a non-hormonal isoflavone derivative, is effective in the prevention and treatment of postmenopausal osteoporosis. The aim of the present investigation was to evaluate the efficacy and toler-ability of ipriflavone and very low doses of equine conjugated estrogens on bone loss in early postmenopausal women. Eighty-three healthy postmenopausal women (50.3±0.7 years) were enrolled for this 1-year multicenter study. All subjects were randomly allocated to receive: double placebo (n=24; group A), placebo plus conjugated equine estrogens 0.30 mg/day (n=31; group B) or conjugated equine estrogens 0.30 mg/day plus oral ipriflavone 200 mg tris in die at meals (n=28; group C), according to a double-masked design. Among women who completed the treatment period (valid completers), those of group A showed a progressive decrease in forearm bone density (FBD; measured by dual photon absorptiometry) that reached 1.7% after 12 months. The women in group B maintained their FBD in the first 6 months of treatment but, at the end of the study, showed a bone loss of 1.4% compared with basal values. By contrast, women in group C showed a significant increase in FBD after 1 year of treatment (+5.6%;p<0.01). Bothvalid completers andintention to treat analyses revealed a significant difference (p<0.05) between group A and group C over the study period. None of the treatments produced significant changes of biochemical markers of bone turnover, while hot flushes and other climacteric symptoms were significantly reduced after the sixth month of treatment in women receiving estrogens. Adverse events were generally mild, and did not differ among the groups. The results of this study suggest that low doses of estrogens combined with ipriflavone could represent a new therapeutic approach to the treatment of the postmenopausal syndrome. 相似文献
28.
G. Wu S. F. Fan Z.-H. Lu R. W. Ledeen S. M. Crain 《Journal of neuroscience research》1995,42(4):493-503
Prolongation of the action potential duration of dorsal root ganglion (DRG) neurons by low (nM) concentrations of opioids occurs through activation of excitatory opioid receptors that are positively coupled via Gs regulatory protein to adenylate cyclase. Previous results suggested GM1 ganglioside to have an essential role in regulating this excitatory response, but not the inhibitory (APD-shortening) response to higher (μM) opioid concentrations. Furthermore, it was proposed that synthesis of GM1 is upregulated by prolonged activation of excitatory opioid receptor functions. To explore this possibility we have utilized cultures of hybrid F11 cells to carry out closely correlated electrophysiological and biochemical analyses of the effects of chronic opioid treatment on a homogeneous population of clonal cells which express many functions characteristic of DRG neurons. We show that chronic opioid exposure of F11 cells does, in fact, result in elevated levels of GM1 as well as cyclic adenosine monophosphate (AMP), concomitant with the onset of opioid excitatory supersensitivity as manifested by naloxone-evoked decreases in voltage-dependent membrane K+ currents. Such elevation of GM1 would be expected to enhance the efficacy of excitatory opioid receptor activation of the Gs/adenylate cyclase/cyclic AMP system, thereby providing a positive feedback mechanism that may account for the remarkable supersensitivity of chronic opioid-treated neurons to the excitatory effects of opioid agonists as well as antagonists. These in vitro findings may provide novel insights into the mechanisms underlying naloxone-precipitated withdrawal syndromes and opioid-induced hyperalgesia after chronic opiatf addiction in vivo. © 1995 Wiley-Liss, Inc. 相似文献
29.
An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 × 165 × 165 μm3 voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambigous results. 相似文献
30.
PACAP is a hypothalamic hypophysiotropic factor that acts upon a number of pituitary cells, including gonadotrophs. In the gonadotroph-derived αT3-1 cell line, PACAP acts via PVR1 receptors to stimulate adenylyl cyclase and phosphoinositidase C. PACAP-stimulated cAMP accumulation is inhibited by protein kinase C-activating phorbol esters in these cells and the current work was undertaken primarily to establish whether it is also subject to homologous regulation. In acute experiments, PACAP27-stimulated cAMP accumulation (intracellular plus extracellular) was measured (in the presence of phosphodiesterase inhibitor) both in intact cells and in cell membranes. The peptide increased cAMP accumulation, but initial rates of PACAP27-stimulated cAMP accumulation were reduced to between 10 and 50% within 10 min of stimulation in both cells and membranes. The initial rate of forskolin-stimulated cAMP accumulation was maintained in membranes but not in intact cells (although the deviation from linearity was less pronounced than with PACAP27). Thus, rapid homologous desensitization to PACAP27 occurs in intact αT3-1 cells, but is not entirely receptor specific. Rapid homologous desensitization of PACAP27-stimulated cAMP accumulation also occurred in the presence of a protein kinase C activating phorbol ester, which inhibited cAMP accumulation without altering the kinetics of the PACAP27 effect. Brief pre-treatment (3 min) with PACAP27 also reduced the ability of PACAP27, but not gonadotrophin-releasing hormone, to cause a spike-type elevation of cytosolic Ca2+ concentration (a consequence of phosphoinositidase C activation). In chronic desensitization studies, pre-treatment for 6 h with PACAP27 caused a dose-dependent (IC50 approximately 10 nM) reduction of PACAP-stimulated cAMP accumulation and down regulated cell surface PVR1 receptors (to approximately 50%). Thus, it appears that PACAP27-stimulated (PVR-1 receptor mediated) adenylyl cyclase undergoes rapid homologous desensitization in αT3-1 cells, which is paralleled by homologous desensitization of PACAP27-stimulated phosphoinositidase C activity and involves mechanisms distinct from those underlying heterologous desensitization by phorbol esters. Chronic desensitization of PACAP-stimulated cAMP accumulation and down-regulation of cell surface PVR-1 receptors also occurs in these cells although the receptor loss may not entirely explain the observed desensitization. 相似文献