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961.
The present experiments were based on the rat resident-intruder paradigm and aimed at better understanding the long-term conditioning properties of this social stress model. Intruders were exposed to aggressive conspecifics residents. During 3 daily encounters, intruders were either defeated or threatened by residents, providing the defeated-threatened (DT) and threatened-threatened (TT) groups respectively, or exposed to a novel empty cage (EC). The effect of such exposures was assessed in 3 separate experiments 8, 14, or 21 days following the last session on both behavior and hypothalamus-pituitary-adrenal (HPA) axis parameters. A specific and persistent behavioral conditioning due to social defeat but also to the sole social threat experience was observed as defensive behaviors and anxiety-like behaviors were observed respectively in DT and TT rats, highlighting a lack of habituation for the conditioning properties of this social stressor. On the other hand, at the earlier time points examined a less specific activation of the HPA axis parameters was found, starting to show habituation at day 21 in EC but not in DT or TT rats. These data give further support to the lasting effects of this social stress model, bestowing a special emphasis upon the impact of its psychological component and upon the relevance of its development and maintenance over time.  相似文献   
962.
Tissue-engineered (TE) corneas were fabricated from porcine collagen cross-linked with 1-ethyl-3-(3-dimethyl aminoproplyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS), and were transplanted into BALB/c mice orthotopically using a full-thickness penetrating keratoplasty (PKP) procedure. The biocompatibility was evaluated by assessing both local and systemic immune responses. Myeloid cells including granulocytes and macrophages were the main infiltrating cells in recipient cornea and in retro-TE corneal membrane which developed 7-10 days post surgery. Sodium citrate was found to be effective in reducing fibrin accumulation in anterior chamber post grafting at early time points, but it did not prevent formation of the retro-TE corneal membrane. No significant T cell activation was observed in the submandibular draining lymph nodes (SMDLN) by flow cytometry. Anti-porcine type I collagen IgG antibodies were detected in the serum of grafted mice from 2 weeks post grafting and the concentration of antibodies increased with time. Overall, porcine collagen-EDC/NHS TE corneas were tolerated well in murine recipients, causing mainly a self-limiting local innate immune response and a low-grade humoral response with little evidence of sustained T cell activation. Retro-TE corneal membrane formation was the main complication and barrier to clarity.  相似文献   
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964.
Vaccines with synthetic peptides induce the immune response to epitopes that bind to several HLA alleles. By using a TEPITOPE algorithm, we selected and analyzed the T-cell responses of peripheral blood mononuclear cells from 29 paracoccidioidomycosis (PCM) patients to peptides of the immunodominant gp43 antigen of Paracoccidioides brasiliensis, the causative agent of PCM.  相似文献   
965.
Many natural compounds have low water solubility and need to be dissolved in organic solvents, or surfactant agents must be used before addition into experimental systems. Therefore, it is necessary to determine their toxicity. Experiments were performed aiming to select solvents to be used in the bioassays, searching new acaricide agents from plants. Laboratory tests were carried out on larvae and adults of the cattle tick Boophilus microplus to determine the sensibility of B. microplus female and larvae to different solvents (acetone, methanol, ethanol and 1% dimethyl sulfoxide) and surfactant agents (1% Tween 80 and 5% Triton X-100) using the larval immersion test (LIT) and adult immersion test (AIT). In the AIT, the effect of the treatments on engorged females was assessed by measuring egg production and hatching rate. Acetone was toxic to the adults promoting mortality of 100%. Methanol and ethanol caused 45.3 and 14.2% of mortality, respectively. The other tested substances were not toxic to the engorged females of B. microplus. In the LIT, it was observed that the larvae were more resistant; after 48 h, about 100% of the larvae were alive in all the treatments except with acetone that caused a mortality of 10%.  相似文献   
966.
By application of the real-time PCR we manage to confirm the diagnosis and occurrence of a disease, which is caused by Bordetella pertussis-pertussis. Using this method we have proven the presence of DNA of Bordetella pertussis in the biological materials (nasopharyngeal swabs). The presence of IS481 genome sequence of Bordetella pertussis was confirmed. This method of detection of pathogens seems to be very rapid, simple, and specific. In the case of adequate technical laboratory equipment it may become very suitable and important supporter in explanation and confirmation of the occurrence of bacterial infections.  相似文献   
967.
BackgroundAcute myeloid leukemia (AML) accounts for approximately 20% of pediatric leukemia cases; 30% of these patients experience relapse. The antileukemia properties of natural killer (NK) cells and their safety profile have been reported in AML therapy. We proposed a phase 2, open, prospective, multicenter, nonrandomized clinical trial for the adoptive infusion of haploidentical K562-mb15-41BBL–activated and expanded NK (NKAE) cells as a consolidation strategy for children with favorable and intermediate risk AML in first complete remission after chemotherapy (NCT02763475).Patients and MethodsBefore the NKAE cell infusion, patients underwent a lymphodepleting regimen. After the NKAE cell infusion, patients were administered low doses (1 × 106/IU/m2) of subcutaneous interleukin-2. The primary study endpoint was AML relapse-free survival. We needed to include 35 patients to demonstrate a 50% reduction in relapses.ResultsSeven patients (median age, 7.4 years; range, 0.78-15.98 years) were administered 13 infusions of NKAE cells, with a median of 36.44 × 106 cells/kg (range, 6.92 × 106 to 193.2 × 106 cells/kg). We observed chimerism in 4 patients (median chimerism, 0.065%; range, 0.05-0.27%). After a median follow-up of 33 months, the disease of 6 patients (85.7%) remained in complete remission. The 3-year overall survival was 83.3% (95% confidence interval, 68.1-98.5), and the cumulative 3-year relapse rate was 28.6% (95% confidence interval, 11.5-45.7). The study was terminated early because of low patient recruitment.ConclusionThis study emphasizes the difficulties in recruiting patients for cell therapy trials, though NKAE cell infusion is safe and feasible. However, we cannot draw any conclusions regarding efficacy because of the small number of included patients and insufficient biological markers.  相似文献   
968.
ObjectiveThe aim of this study is to analyze the prognostic role of lymph-vascular space invasion (LVSI), evaluated in a semi-quantitative fashion on prognosis of early stage, low risk endometrial cancer (EC).MethodsWe enrolled patients who underwent surgery for endometrial cancer between 2003 and 2018 in two referral cancer center. All patients had endometrioid EC, G1–G2, with myometrial invasion <50%, and no lymph-node involvement. LVSI was analyzed in a semi-quantitative way, according to a 3-tiered scoring system in absent, focal and substantial.ResultsAmong 524 patients, any positive LVSI was found in 57 patients (10.9%) with focal LVSI (n=35, 6.7%) and substantial LVSI (n=22, 4.2%). Substantial LVSI was associated to higher rate of G2 (p<0.001), myometrial infiltration (p=0.002) and greater tumor dimensions (p=0.014). Patients with substantial LVSI were more likely to receive adjuvant treatment (6.6% vs. 52.6%, p<0.001). The 5-year OS was 99.5% in patients with absent LVSI and 70.6% in those with substantial LVSI (p<0.001). The 5-year disease free survival (DFS) was 93.6% in patients with absent LVSI and 56.5% in those with substantial LVSI (p<0.001). The rate of distant failures increased from 1.8% for absent LVSI to 22.7% for substantial LVSI (p=0.002). In univariate analysis substantial LVSI was the strongest predictor of poor overall survival (hazard ratio [HR]=11.9, p=0.001). Multivariate analysis showed that substantial LVSI was an independent predictive factor of both recurrence (HR=5.88, p=0.001) and distant failure (HR=10.6, p=0.006).ConclusionsSubstantial LVSI represents the strongest independent risk factor for decreased survival and distant relapse, indicating a role for potential hematogenous dissemination.  相似文献   
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970.
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