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91.
Extracellular purines and pyrimidines are important signaling molecules acting via purinergic cell-surface receptors in neurons, glia, and glia-like cells such as sustentacular supporting cells (SCs) of the olfactory epithelium (OE). Here, we thoroughly characterize ATP-induced responses in SCs of the OE using functional Ca2+ imaging. The initial ATP-induced increase of the intracellular Ca2+ concentration [Ca2+]i always occurred in the apical part of SCs and subsequently propagated toward the basal lamina, indicating the occurrence of purinergic receptors in the apical part of SCs. The mean propagation velocity of the Ca2+ signal within SCs was 17.10 +/- 1.02 microm/s. ATP evoked increases in [Ca2+]i in both the presence and absence of extracellular Ca2+. Depletion of the intracellular Ca2+ stores abolished the responses. This shows that the ATP-induced [Ca2+]i increases were in large part, if not entirely, due to the activation of G protein-coupled receptors followed by Ca2+ mobilization from intracellular stores, suggesting an involvement of P2Y receptors. The order of potency of the applied purinergic agonists was UTP > ATP > ATPgammaS (with all others being only weakly active or inactive). The ATP-induced [Ca2+]i increases could be reduced by the purinergic antagonists PPADS and RB2, but not by suramin. Our findings suggest that extracellular nucleotides in the OE activate SCs via P2Y2/P2Y4-like receptors and initiate a characteristic intraepithelial Ca2+ wave.  相似文献   
92.
BACKGROUND: Hippocampal volume reduction is a well replicated finding in schizophrenia. Evidence indicates a contribution of genetic and environmental factors, especially the influence of obstetric complications to this volume reduction. The aim of this study was to compare hippocampal volume of schizophrenic patients as well as and their relatives with control subjects and to quantify the additional contribution of obstetric complications. METHODS: T1 weighted MRI brain scans of 50 schizophrenic patients, 88 first-degree relatives and 53 healthy control subjects were used to perform volumetric measurements on the left and right hippocampus. A set of clinical measures including obstetric complications were recorded for all family members. RESULTS: Numerically our measurements revealed a hippocampal volume reduction in schizophrenic patients (left: - 14%, right: - 15%) and, although less pronounced, in their unaffected relatives (left: - 6%, right: - 10%). Noted differences in hippocampal volume between schizophrenic patients and controls were only significant for the left side. Hippocampal volumes of patients and their relatives with obstetric complications were reduced bilaterally. CONCLUSIONS: Hippocampal volume reduction is present in schizophrenic patients and their first-degree relatives, suggesting an influence of genetic factors.. In addition, however, obstetric complications have also been shown to play a major role.  相似文献   
93.
Until recently, IgE-activated mast cells have been regarded merely as effector cells of adaptive immune responses, involved in allergic reactions and mucosal immunity to parasites. Herein, we report that murine dermal mast cells, activated by local administration of a cream containing the synthetic TLR7 ligand imiquimod, are essential to initiate an early inflammatory reaction. The mast-cell-derived cytokines TNF-alpha and IL-1beta play an important role in this process. Furthermore, TLR7-activated mast cells are also able to promote the emigration of Langerhans cells, which partly depends on the expression of mast-cell-derived IL-1beta. We have previously shown that TLR7 ligation enhances transcutaneous immunization evoked by topical application of vaccine antigens to the skin, a procedure that directly targets skin-resident antigen-presenting cells. Consequently, we now demonstrate here that the capacity to mount a peptide-specific cytotoxic T-lymphocyte response following transcutaneous immunization using imiquimod as adjuvant is severely impaired in mast-cell-deficient mice. Thus, these findings demonstrate the potent versatility of alternatively activated mast cells at the interface of innate and adaptive immunity.  相似文献   
94.
PURPOSE: To evaluate the potential prognostic impact of the effect of radiotherapy (RT) on motor function and of the post-RT ambulatory status on survival in metastatic spinal cord compression (MSCC) patients. METHODS AND MATERIALS: Of 1,852 patients irradiated for MSCC, 778 patients (42%) received short-course RT and 1,074 (58%) received long-course RT. The effect of RT on motor function (improvement vs. no change vs. deterioration) and the ambulatory status after RT (ambulatory vs. nonambulatory) were evaluated with respect to survival. RESULTS: The actuarial survival rate of the entire cohort was 56% at 6 months, 43% at 12 months, and 32% at 24 months. The patients in whom motor function improved after RT had a significantly better 1-year survival rate than those who had no change or deterioration of motor function (75% vs. 40% and 3%, p < 0.001). The 1-year survival rate of the patients who were ambulatory after RT was significantly better than for those who were not ambulatory (63% vs. 4%, p < 0.001). The results were confirmed in multivariate analysis. CONCLUSIONS: The response to RT and the post-RT ambulatory status are important predictors for survival in MSCC patients. This finding can be used by physicians to stratify future studies, plan further therapy, and improve follow-up strategy in these patients.  相似文献   
95.
PURPOSE: Patients with cancer of unknown primary (CUP) account for about 10% of patients with metastatic spinal cord compression (MSCC). This study aims to define the appropriate radiation regimen for these patients. METHODS AND MATERIALS: Data of 143 CUP patients irradiated for MSCC were retrospectively evaluated. Short-course radiotherapy (RT) (1x8 Gy, 5x4 Gy, n = 68) and long-course RT (10x3 Gy, 15x2.5 Gy, 20x2 Gy, n = 75) plus 8 further potential prognostic factors (age, gender, performance status, visceral metastases, other bone metastases, number of involved vertebrae, ambulatory status, time of developing motor deficits before RT) were compared for functional outcome and survival. RESULTS: Improvement of motor function occurred in 10% of patients, no further progression of motor deficits in 57%, and deterioration in 33%. On multivariate analysis, functional outcome was positively associated with slower development of motor deficits (p < 0.001), absence of visceral metastases (p = 0.008) and other bone metastases (p = 0.027), and ambulatory status (p = 0.054), not with the radiation regimen (p = 0.74). Recurrence of MSCC in the irradiated region occurred in 7 patients after median 6 months. Median survival was 4 months. On multivariate analysis, better survival was significantly associated with absence of visceral metastases (p < 0.001), absence of other bone metastases (p = 0.005), ambulatory status (p = 0.001), and slower development of motor deficits (p = 0.030). CONCLUSIONS: For MSCC treatment in patients with CUP, no significant difference was observed between short-course and long-course RT regarding functional outcome and survival. Short-course RT appears preferable, at least for patients with a poor predicted survival, as it is more patient convenient and more cost-effective.  相似文献   
96.
BACKGROUND: Breast cancer is one of the most frequent types of cancer with fatal outcome worldwide. The use of breast conserving lumpectomy followed by radiation therapy is common and has been shown to be a strategy competitive to mastectomy in preventing mortality caused by breast cancer. However, breast irradiation, particularly applied after pre-irradiation chemotherapy, frequently leads to serious short- and long-term side-effects, the prediction of which is highly desirable in terms of individual therapy planning. For these purposes, minimal-invasive molecular blood analysis is considered as a powerful diagnostic tool: molecular interplay in blood is highly informative and may predict individual side-effects of therapy. MATERIALS AND METHODS: Ex vivo comparative protein expression profiling was performed in circulating leukocytes isolated from fresh blood samples of seven breast cancer patients before lumpectomy and consequently at several checkpoints under radiation treatment (0-60 Gy). Protein expression patterns were investigated by two-dimensional polyacrylamide gel electrophoresis followed by protein spot identification using matrix assisted laser desorption/ ionisation -- time of flight. Specific expression levels of highly affected differentially expressed proteins were quantified by Western blotting. RESULTS: The radiation treatment caused individual extensive alterations in expression patterns of leukocytes in the patients tested. In particular, a key regulator of redox status, thioredoxin, and the free-radical detoxification cascade members, SOD-2 and catalase, were highly affected. In spite of the high diversity of individual expression levels, characteristic protein expression patterns were recognized and patients were grouped according to the similarities found. CONCLUSION: Characteristic expression patterns in circulating leukocytes might provide novel molecular targets for prediction of therapy side-effects and improve individual therapy planning for breast cancer patients, thus avoiding unnecessary and excessive treatment-related toxicity. Molecular candidates and specific patterns are demonstrated in this work.  相似文献   
97.
98.
Rades D  Bohlen G  Pluemer A  Veninga T  Hanssens P  Dunst J  Schild SE 《Cancer》2007,109(12):2515-2521
BACKGROUND: The objective of this study was to compare stereotactic radiosurgery (SRS) alone with resection plus whole-brain radiotherapy (WBRT) for the treatment of patients in recursive partitioning analysis (RPA) class 1 and 2 who had 1 or 2 brain metastases. METHODS: Two hundred six patients in RPA class 1 and 2 who had 1 or 2 brain metastases were analyzed retrospectively. Patients in Group A (n = 94) received from 18 grays (Gy) to 25 Gy SRS, and patients in Group B (n = 112) underwent resection of their metastases and received 10 x 3 Gy/20 x 2 Gy WBRT. Eight other potential prognostic factors were evaluated regarding overall survival (OS), brain control (BC), and local control (LC) of treated metastases: age, sex, performance status, tumor type, number of brain metastases, extracranial metastases, RPA class, and interval from tumor diagnosis to treatment of brain metastases. RESULTS: A comparison of the 2 treatment groups did not reveal significantly different OS (P = .19), BC (P = .52), or LC (P = .25). In RPA subgroup analyses, outcome also did not differ significantly for either RPA class of patients (P values from .21 to .83). On multivariate analysis, improved OS was associated with age < or =60 years (relative risk [RR], 1.75; P = .002), better performance status (RR, 1.67; P = .015), no extracranial metastases (RR, 2.84; P < .001), interval from tumor diagnosis to treatment >12 months (RR, 1.70; P = .003), and RPA class 1 (RR, 1.51; P = .016). Improved BC was associated with a single metastasis (RR, 1.54; P = .034) and an interval from tumor diagnosis to treatment >12 months (RR, 1.58; P = .019), and improved LC was associated with an interval from tumor diagnosis to treatment >12 months (RR, 1.59; P = .047). CONCLUSIONS: SRS alone appeared to be as effective as resection plus WBRT in the treatment of 1 or 2 brain metastases for patients in RPA class 1 and 2. Patient outcomes were associated with age, Karnofsky performance status, number of brain metastases, extracranial metastases, RPA class, and interval from tumor diagnosis to treatment.  相似文献   
99.
Olivier KR  Schild SE  Morris CG  Brown PD  Markovic SN 《Cancer》2007,110(8):1791-1795
BACKGROUND: Oncologists are often reluctant to recommend radiotherapy (RT) to palliate metastatic melanoma due to a perception that this tumor is "radioresistant." The Mayo Clinic experience was analyzed to determine the efficacy of palliative RT. METHODS: Eighty-four consecutive patients with 114 lesions that were not metastatic to the central nervous system (CNS) were evaluated for the response of the presenting symptom, the duration of response, and survival after RT. The median dose delivered was 30 grays (Gy) and the median biologic effective dose (BED) was 39.0 Gy(10). Performance status was not uniformly available for all patients. RESULTS: Complete resolution of the presenting symptom occurred in 10 lesions (9%). Of the lesions treated, there was partial improvement in 86 (75%), no change in 12 (11%), and worsening in 6 (5%) lesions. The median survival was 3.8 months and freedom from disease progression (FFP) for individual lesions was 6 months. Patients treated with >30 Gy had significantly longer FFP compared with patients given 30 Gy had a significantly longer survival than those given a lesser dose (median of 2 months vs 8 months; P < .0001). Similarly, patients receiving a BED >39.0 Gy(10) also were found to have longer FFP (P = .03) and survival (median of 2 months vs 8 months; P < .0001) compared with those receiving a BED 30 Gy and a BED >39.0 Gy(10) were found to be associated with longer palliation.  相似文献   
100.
Rades D  Lohynska R  Veninga T  Stalpers LJ  Schild SE 《Cancer》2007,110(11):2587-2592
BACKGROUND: The majority of breast cancer patients with brain metastases receive whole-brain radiotherapy (WBRT) and have a survival of only a few months. A short WBRT regimen would be preferable if it provides survival that is similar to that achieved with longer programs. This retrospective study compared survival and local control within the brain resulting from short-course WBRT with longer programs in 207 breast cancer patients. METHODS: Sixty-nine patients treated with 5 fractions of 4 grays (Gy) each given within 5 days were compared with 138 patients treated with 10 fractions of 3 Gy each given over 2 weeks or 20 fractions of 2 Gy each given over 4 weeks. Six additional potential prognostic factors were investigated: age, Karnofsky performance score (KPS), number of brain metastases, the presence of extracranial metastases, interval from tumor diagnosis to WBRT, and recursive partitioning analysis (RPA) class. RESULTS: On univariate analysis, the WBRT regimen was not found to be associated with survival (P=.254) or local control (P=.397). Improved survival was associated with a KPS>70 (P<.001), single brain metastasis (P=.023), the absence of extracranial metastases (P<.001), and lower RPA class (P<.001). On multivariate analysis, which was performed without RPA class because this is a confounding variable, KPS (relative risk [RR] of 4.00; P<.001) and the presence of extracranial metastases (RR of 1.54; P=.024) maintained statistical significance. On univariate analysis, local control was associated with KPS (P<.001) and RPA class (P<.001). On multivariate analysis, local control was found to be associated with a KPS>70 (RR of 5.75; P<.001). CONCLUSIONS: Short-course WBRT with 5 fractions of 4 Gy each resulted in survival and local control that were similar to longer programs in breast cancer patients with brain metastases. The dose of 5 fractions of 4 Gy each appears preferable for the majority of these patients because it is less time consuming and more convenient.  相似文献   
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