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Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
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Background The role of the vagal nerve in the autonomic nervous system is widely well known. Recently, an additional function was revealed serving as a connector between the nervous and immune system. This connection is called the “cholinergic inflammatory pathway.” Through stimulation of the acetylcholine receptors located upon the macrophages, the “unspecific” immune system can be directly influenced. Methods The vagal nerve was completely transected directly posterior to its passage through the diaphragm. The effect of complete vagotomy was analyzed using a murine model of polymicrobial peritonitis (colon ascendens stent peritonitis, CASP). Survival and clinical course of vagotomized or sham-operated mice were analyzed in the CASP model. Results After CASP surgery, vagotomy led to a significantly increased mortality (64.7%) in comparison to sham-vagotomized animals (34%). No difference in the bacterial load of various tissues (lung, liver, spleen, blood, lavage fluid, and kidney) from septic animals with or without vagotomy was observed. Vagotomized animals reveal elevated serum cytokine levels (TNF, IL-6, IL-10, and MCP-1) 20 h after the induction of polymicrobial peritonitis. Conclusion The vagal nerve is therefore an important modulator of the immune system. W. Kessler and T. Traeger contributed equally to this work Best of Forum Papers presented at the Annual Meeting of the German Society of Surgery, 2–5 May 2006, Berlin, Germany  相似文献   
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The regulation of heat shock protein 90 kDa (hsp90) by estradiol was analyzed in the rat ventromedial hypothalamus (VMH) and uterus by one-dimensional gel electrophoresis/Western blots. Protein from VMH and uterus (35 micrograms/sample) was resolved on 8% acrylamide gels, transferred to polyvinyldifluoride filters, and processed for immunoblotting using an anti-hsp90 antibody. Hsp90-specific bands were visualized on film using enhanced chemiluminescence and quantitated using a laser scanning densitometer. Hsp90 protein levels were significantly elevated in VMH at 12 h (p less than 0.01), and in uterus at 18 h (p less than 0.05) following estradiol injection (10 micrograms, s.c.). Immunocytochemical analysis for hsp90 localization by cell types showed that, in brain, hsp90 immunoreactivity was primarily neuronal. In the uterus, hsp90 immunoreactivity was most evident following treatment with estradiol, and was found primarily in the glandular epithelia; staining was less prominent in myometrium, stroma, and in the luminal epithelium. Thus, increased hsp90 levels may mediate some cellular responses to estrogen in specific cell types in both uterus and brain.  相似文献   
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In the lateral longissimus muscle (LL) of ovariectomized, female rats anesthetized with low surgical doses of urethane (1.0 g/kg), cutaneous reflexes with similar EMG and response patterns could be elicited from CNS-intact rats and from rats 24 h after complete thoracic spinal cord transection. The probability of eliciting a response to contralateral cutaneous nerve stimulation alone is much lower in rats with complete spinal transections compared to CNS-intact rats. For both CNS-intact and spinal-transected rats, responses to ipsilateral cutaneous nerve stimulation had a shorter latency and required significantly less current on average than responses to contralateral stimulation. The respective currents for eliciting threshold responses to ipsi- and contralateral stimulation are less for CNS-intact than spinal-transected rats. For both CNS-intact and spinal-transected rats, responses to bilateral cutaneous nerve stimulation were inconsistent in the same animal from run to run. With the variability of response at this anesthetic level, no consistent effects of progesterone (acute, i.v.) or estrogen (acute, i.v. and pretreatment, s.c.) were observed in spinal-transected rats. Intravenous progesterone reduced early, unilateral responses in CNS-intact rats anesthetized with 1.0 g of urethane/kg. For both CNS-intact and spinal-transected rats, additional anesthesia during EMG recording produced a gradual decline in response magnitude which could be recovered with a modest increase in stimulus intensity. However, spinal-transected rats appear to require less anesthesia to reduce comparable responses. The results suggest that supraspinal input is especially effective for facilitating contralateral cutaneous reflexes in back muscles, whereas it contributes more equally with afferent input and segmental circuitry to the efficacy of ipsilateral cutaneous reflexes.  相似文献   
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Contact between the developing forebrain and the ingrowing central processes of the olfactory, vomeronasal and terminal nerves is preceded by a migration of neural cell adhesion molecule (NCAM)-immunoreactive cells from the epithelium of the olfactory pit and the formation of an NCAM-immunoreactive cellular aggregate in the mesenchyme between the olfactory pit and the forebrain. The axons of the olfactory, vomeronasal, and terminal nerves, also NCAM-immunoreactive, grow into the cellular aggregate, which as development proceeds, becomes continuous with the rostral tip of the forebrain. The lateral and more rostral part of the cellular aggregate receives the ingrowing axons of the olfactory nerves and becomes the olfactory nerve layer of the olfactory bulb. The medial, more caudal part receives the central processes of the vomeronasal and terminal nerves. The vomeronasal nerve ends in the accessory olfactory bulb. The central processes of the terminal nerve end in the medial forebrain. Luteinizing hormone-releasing hormone (LHRH)-immunoreactive neurons, like the vomeronasal and terminal nerves, originate from the medial part of the olfactory pit. These LHRH cells migrate into the brain along and within a scaffolding formed by the NCAM-immunoreactive axons of the vomeronasal and terminal nerves, and they are never seen independent of this NCAM scaffold as they cross the nasal lamina propria. The results suggest that: (1) NCAM is likely to be necessary for scaffold formation, and (2) the scaffold may be essential for the subsequent migration of LHRH neurons into the brain. Because they aggregate, migrating LHRH-immunoreactive neurons, on which we did not detect NCAM immunoreactivity, may interact via other cell adhesion molecules (CAM). Inasmuch as the interaction between the LHRH-immunoreactive neurons and the NCAM-immunoreactive scaffold is heterotypic, the possibility of a heterophilic (NCAM to other CAM) interaction is not ruled out. These findings focus our attention on the functional role of NCAM in this migratory system.  相似文献   
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The paper reports on acylaminoalkylbenzenesulfonamide derivatives with special heterocyclic acyl substituents. The compounds are characterized by an oxygen atom in ortho position to the carboxamide group of the heterocyclic acyl moiety. Several compounds show blood glucose lowering activities in animals similarly to glibenclamide.  相似文献   
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The efficiency of preoperative laboratory screening of normal, healthy patients was investigated. Preoperative test results of 1311 consecutive patients were collected. Data on haemoglobin, serum potassium, serum creatinine and serum ALAT were routinely obtained. 736 patients were classified by history and physical examination as normal healthy persons not having any systemic disorder. In this group of patients no clinically relevant abnormal laboratory results were found under the age of 60 years. In the group of 60 years and older a significant number had elevated serum creatinine values.  相似文献   
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