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991.
AIM: To evaluate the management, clinical outcome and cost implications of three different treatment regimes for simple elbow dislocations.METHODS: Following institutional board approval, we performed a retrospective review of all consecutive patients treated for simple elbow dislocations in a Level I trauma centre between January 2008 and December 2010. Based on the length of elbow immobilisation (LOI), patients were divided in three groups (Group I, < 2 wk; Group II, 2-3 wk; and Group III, > 3 wk). Outcome was considered satisfactory when a patient could achieve a pain-free range of motion ≥ 100° (from 30° to 130°). The associated direct medical costs for the treatment of each patient were then calculated and analysed.RESULTS: We identified 80 patients who met the inclusion criteria. Due to loss to follow up, 13 patients were excluded from further analysis, leaving 67 patients for the final analysis. The mean LOI was 14 d (median 15 d; range 3-43 d) with a mean duration of hospital engagement of 67 d (median 57 d; range 10-351 d). Group III (prolonged immobilisation) had a statistically significant worse outcome in comparison to Group I and II (P = 0.04 and P = 0.01 respectively); however, there was no significant difference in the outcome between groups I and II (P = 0.30). No statistically significant difference in the direct medical costs between the groups was identified.CONCLUSION: The length of elbow immobilization doesn’t influence the medical cost; however immobilisation longer than three weeks is associated with persistent stiffness and a less satisfactory clinical outcome.  相似文献   
992.

Background

Radiation therapy (RT) comprises a key component in the treatment of breast cancer. Radiation-induced skin toxicity is the major adverse event experienced by patients; however, radiodermatitis (RD) prevention and management remains trivial. It is proven that photobiomodulation (PBM) therapy using light-emitting diode (LED) increases wound healing and depicts an anti-inflammatory effect. This single-institute study evaluates the beneficial role of PBM-LED in preventing/reducing RD during breast cancer RT.

Patients and methods

Of 70 consecutively treated patients, 25 patients were treated with PBM-LED twice a week prior to adjuvant 3D conformal RT after breast-conserving surgery. RD was reported using Common Toxicity Criteria for Adverse Events Version 4.0 and pain intensity using a visual analog scale (VAS). For comparison, a control group (n = 45) received RT without PBM-LED. In addition, a “matched” group (n = 25) was generated from the control group based on propensity for potentially confounding variables.

Results

In the PBM group, 22 patients (88%) presented grade 1 and 3 (12%) grade 2 RD. In the control group, 25 patients (55.6%) developed grade 1 reactions, 18 patients (40%) grade 2, and 2 (4.4%) patients grade 3 RD. Concerning pain intensity, 15 patients (60%) of the PBM treatment arm reported no pain, 5 patients (20%) VAS 2, and 5 (20%) VAS 3. In the control group, 13 patients (28.9%) reported no pain, 2 (4.4%) VAS 1, 7 (15.6%) VAS 2, 9 patients (20%) reported VAS 3, 12 (26.7%) patients VAS 4, and 2 (4.4%) patients VAS 5.

Conclusion

PBM-LED therapy applied prior to RT might be effective in decreasing the incidence and sequelae of radiation-induced skin toxicity in breast cancer patients treated with breast-conserving surgery.
  相似文献   
993.
This post hoc analysis of a phase 3 trial explored the effect of pixantrone in patients (50 pixantrone, 47 comparator) with relapsed or refractory aggressive B‐cell non‐Hodgkin lymphoma (NHL) confirmed by centralized histological review. Patients received 28‐d cycles of 85 mg/m2 pixantrone dimaleate (equivalent to 50 mg/m2 in the approved formulation) on days 1, 8 and 15, or comparator. The population was subdivided according to previous rituximab use and whether they received the study treatment as 3rd or 4th line. Median number of cycles was 4 (range, 2–6) with pixantrone and 3 (2–6) with comparator. In 3rd or 4th line, pixantrone was associated with higher complete response (CR) (23·1% vs. 5·1% comparator, P = 0·047) and overall response rate (ORR, 43·6% vs. 12·8%, P = 0·005). In 3rd or 4th line with previous rituximab (20 pixantrone, 18 comparator), pixantrone produced better ORR (45·0% vs. 11·1%, P = 0·033), CR (30·0% vs. 5·6%, P = 0·093) and progression‐free survival (median 5·4 vs. 2·8 months, hazard ratio 0·52, 95% confidence interval 0·26–1·04) than the comparator. Similar results were found in patients without previous rituximab. There were no unexpected safety issues. Pixantrone monotherapy is more effective than comparator in relapsed or refractory aggressive B‐cell NHL in the 3rd or 4th line setting, independently of previous rituximab.  相似文献   
994.
995.
996.
Germinal centers (GCs) are sites of B cell proliferation, somatic hypermutation, and selection of variants with improved affinity for antigen. Long-lived memory B cells and plasma cells are also generated in GCs, although how B cell differentiation in GCs is regulated is unclear. IL-21, secreted by T follicular helper cells, is important for adaptive immune responses, although there are conflicting reports on its target cells and mode of action in vivo. We show that the absence of IL-21 signaling profoundly affects the B cell response to protein antigen, reducing splenic and bone marrow plasma cell formation and GC persistence and function, influencing their proliferation, transition into memory B cells, and affinity maturation. Using bone marrow chimeras, we show that these activities are primarily a result of CD3-expressing cells producing IL-21 that acts directly on B cells. Molecularly, IL-21 maintains expression of Bcl-6 in GC B cells. The absence of IL-21 or IL-21 receptor does not abrogate the appearance of T cells in GCs or the appearance of CD4 T cells with a follicular helper phenotype. IL-21 thus controls fate choices of GC B cells directly.The immunological memory that develops during T cell–dependent (TD) immune responses comprises populations of plasma cells and recirculating antigen-experienced B and T lymphocytes (Tarlinton, 2006). Two compartments of humoral memory, plasma cells and memory B cells, are generated in germinal centers (GCs) that develop within the secondary lymphoid organs during TD responses (Tarlinton, 2006). Although composed primarily of B lymphocytes, GCs contain small numbers of CD4+ T cells, dendritic cells, and macrophages and develop in association with antigen localized on the surface of follicular dendritic cells (Haberman and Shlomchik, 2003; Allen et al., 2007). After a period of B cell proliferation, several processes are initiated within the GC that affect affinity maturation whereby the mean binding affinity of antigen-specific antibody increases as a function of time (MacLennan, 1994; Allen et al., 2007). Affinity maturation is driven in large part by the somatic hypermutation (SHM) of the immunoglobulin V genes of proliferating GC B cells, a process which is mediated by the enzyme activation-induced cytidine deaminase (AID). B cells expressing antigen receptors of improved affinity, usually as a result of SHM, are preserved preferentially. Iterations of proliferation, mutation, and avidity-based selection improve the mean affinity of the responding B cell population (MacLennan, 1994; Allen et al., 2007).Normally, in an immune response to a protein antigen the vast majority of memory B cells and bone marrow plasma cells arise from the somatically diversified affinity-matured population of GC B cells (Tarlinton, 2006). It is inferred that avidity for antigen is a major determinant in plasma cell differentiation of GC B cells, whereas memory B cell formation is more influenced by survival (Lanzavecchia and Sallusto, 2002; Phan et al., 2006; Tarlinton, 2006). It also appears that both types of post-GC B cell are produced throughout the GC reaction rather than being released into the circulation in a single event (Blink et al., 2005). The persistence and continued activity of GC, which is indicated by the continued production of plasma cells and memory B cells and the increasing frequency of V gene mutation, implies that a proportion of GC B cells remain within the GC and undergo additional rounds of proliferation, mutation, and selection (MacLennan, 1994; Allen et al., 2007). B cells within GC therefore have several possible fates: death, division with or without SHM, or differentiation into either the memory B cell or plasma cell compartments.GC persistence, development, and function absolutely require CD4+ T cells. T cells activated by antigen-presenting dendritic cells migrate into the B cell area in part as a result of their up-regulation of CXCR5, a chemokine receptor normally restricted to B cells (Allen et al., 2007). Indeed, the expression of CXCR5 contributes to the definition of what are now called T follicular helper (Tfh) cells (Vinuesa et al., 2005). In addition to CXCR5, Tfh cells are distinguished from other CD4 T cells by their elevated expression of ICOS and CD40L (Vinuesa et al., 2005), both of which are critical for the initiation and maintenance of the GC (Tarlinton, 2006). Intriguingly, up-regulation of many of the molecules that define the Tfh phenotype appears to be mediated by Bcl-6, which is required for their development in a cell-intrinsic manner (Johnston et al., 2009). Tfh cells are also enriched for secretion of IL-21 (Chtanova et al., 2004; Nurieva et al., 2008) and IL-4 (Reinhardt et al., 2009). IL-21 is associated with growth and differentiation of many types of lymphocytes, including B and T cells (Ettinger et al., 2008). The effects of IL-21 on B cells vary depending on the context. In vivo, IL-21R deficiency leads to a state of pan-hypogammaglobulinaemia while promoting high titers of IgE (Ozaki et al., 2002). In vitro, IL-21 has been shown to increase both Blimp-1 and Bcl-6 in B cells (Ozaki et al., 2004; Arguni et al., 2006), suggesting an ability for IL-21 to influence multiple aspects of B cell differentiation. Recent data support the notion that IL-21 has a critical, possibly obligatory, role in the development of Tfh cells and, through this, on the formation of GC (Nurieva et al., 2008; Vogelzang et al., 2008), whereas other data suggest a less universal association (Linterman et al., 2009). IL-21 has also been shown to augment the formation of Th17 cells (Korn et al., 2007; Nurieva et al., 2007; Zhou et al., 2007), which have been shown to both secrete IL-21 and promote GC formation in a mouse model of autoimmunity (Hsu et al., 2008), strengthening the view that the effects of IL-21 on GC activity are T cell mediated. An earlier study, however, using IL-21R–deficient mice reported GC and memory development to be normal (Ozaki et al., 2002), raising uncertainty as to exactly what the requirement of IL-21 may be in the GC reaction, on which cell types it may act, and what its activities might be. This uncertainty has been heightened by recent publications suggesting that IL-4 is a key mediator of Tfh activity (King and Mohrs, 2009; Reinhardt et al., 2009).Given the multitude of potential roles for IL-21 on lymphocyte behavior (Ettinger et al., 2008), we wished to assess the development of a humoral immune response in mice lacking IL-21 or the IL-21R. These experiments confirmed a role for IL-21 in the formation of plasma cells, contradicted a mandatory autocrine role for IL-21 in Tfh development or function, and revealed a previously undefined role for this cytokine in the GC reaction and the regulation of their output. These actions of IL-21 on B cells were direct, as they were replicated by the selective absence of the IL-21R on B cells and not on T cells, suggesting that the major activity of IL-21 in the GC is on B cells and is not to establish or maintain cells of a Tfh phenotype.  相似文献   
997.
Metaphase comparative genomic hybridisation (CGH) studies indicate that chromosomes 4, 5, 6, 13, 14, 15 and 18 are frequently deleted in primary ovarian cancers (OCs). Therefore we used microcell‐mediated chromosome transfer (MMCT) to establish the functional effects of transferring normal copies of these chromosomes into 2 epithelial OC cell lines (TOV112D and TOV21G). The in vitro neoplastic phenotype (measured as anchorage dependent and independent growth and invasion) was compared between recipient OC cell lines and multiple MMCT hybrids. Chromosomes 6 and 18 showed strong evidence of functional, neoplastic suppression for multiple hybrids in both cell lines. We also found evidence in 1 cancer cell line suggesting that chromosomes 4, 13 and 14 may also cause functional suppression. Array CGH and microsatellite analyses were used to characterise the extent of genomic transfer in chromosome 6 and 18 hybrids. A 36 MB deletion on chromosome 6 in 2 hybrids from 1 cell line mapped the candidate region proximal to 6q15 and distal to 6q22.2; and an ~10 MB candidate region spanning the centromere on chromosome 18 was identified in 2 hybrids from the other cell line. These data support reported functional effects of chromosome 6 in OC cell lines; but to our knowledge, this is the first time that functional suppression for chromosome 18 has been reported. This suggests that these chromosomes may harbour tumour suppressor‐“like” genes. The future identification of these genes may have a significant impact on the understanding and treatment of the disease and the identification of novel therapeutic targets. © 2008 Wiley‐Liss, Inc.  相似文献   
998.
COVID-19-related restrictions impacted weight and weight-related factors during the initial months of the pandemic. However, longitudinal analyses are scarce. An online, longitudinal study was conducted among self-selected UK adults (n = 1818), involving three surveys (May–June, August–September, November–December 2020), covering anthropometric, sociodemographic, COVID-19-related and behavioural measures. Data were analysed using generalised estimating equations. Self-reported average weight/body mass index (BMI) significantly increased between the May–June period and the August–September period (74.95 to 75.33 kg/26.22 kg/m2 to 26.36kg/m2, p < 0.001, respectively), and then significantly decreased to November–December (to 75.06 kg/26.27 kg/m2, p < 0.01), comparable to May–June levels (p = 0.274/0.204). However, there was great interindividual variation, 37.0%/26.7% increased (average 3.64 kg (95% confidence interval: 3.32, 3.97)/1.64 kg/m2 (1.49, 1.79)), and 34.5%/26.3% decreased (average 3.59 kg (3.34, 3.85)/1.53 kg/m2 (1.42, 1.63)) weight/BMI between May–June and November–December. Weight/BMI increase was significantly negatively associated with initial BMI, and positively associated with monthly high fat, salt and sugar (HFSS) snacks intake and alcohol consumption, and for BMI only, older age. Associations were time-varying; lower initial BMI, higher HFSS snacks intake and high-risk alcohol consumption were associated with maintaining weight/BMI increases between August–September and November–December. The average weight/BMI of UK adults fluctuated between May–June and November–December 2020. However, the substantial interindividual variation in weight/BMI trajectories indicates long-term health impacts from the pandemic, associated with food and alcohol consumption.  相似文献   
999.
Background  Examinations using ionizing radiation are frequently used in the evaluation of disease activity in children affected by idiopathic inflammatory bowel disease (IBD). Objective  To develop an MR imaging protocol without the need for fluoroscopic insertion of an enteral tube and to assess the disease activity in children with IBD. Materials and methods  Included in the study were 37 children (22 girls and 15 boys; age range 7–15 years, mean 11.67 years) with IBD who underwent MR imaging of the small bowel. Of these 37 children, 32 had Crohn disease and 5 had indeterminate colitis. A water solution containing herbal fibres was administered orally or through a nasogastric tube. Patients were imaged on a 1.5-T MR scanner with T1-weighted and Τ2-weighted sequences followed by a dynamic study using 3-D T1-W images after intravenous administration of gadolinium. Results  The percentage enhancement of the bowel wall was significantly increased in patients with abnormal C-reactive protein (CRP) values compared to patients with CRP values in the normal range (P<0.001). A relatively weak but significant correlation between percentage enhancement of the bowel wall and CRP values was noted during all phases of enhancement. Conclusion  This MR imaging protocol is a safe and well-tolerated method for evaluating disease activity and extraintestinal manifestations of IBD in children.  相似文献   
1000.
T-cell activation, particularly of CD8(+) cells, is invariably associated with viral infections. We now provide evidence for the activation of T cells in patients with localized bacterial soft tissue infections. During acute disease we detected in the peripheral blood of these patients, small though conspicuous populations of CD4(+) CD28(+) CD11b(+) and CD8(+) CD28(+) CD11b(+) cells, indicative of an expansion of effector T cells. Moreover, we identified CD4(+) and CD8(+) cells at the infected site, in addition to highly activated polymorphonuclear neutrophils (PMN). In keeping with their role as first-line defence, PMN were preponderant, but T cells amounted to 20% of the infiltrated cells. The majority of the infiltrated T cells expressed CXCR6, a homing receptor for non-lymphoid tissue. The infiltrated T cells produced interferon-gamma (IFN-gamma), while the peripheral blood cells obtained at the same time did not. In conclusion, in response to localized bacterial infections, T cells are activated and recruited to the infected site. We propose that these T cells, e.g. by producing IFN-gamma, enhance the efficiency of the infiltrated phagocytic cells, particularly of the PMN, thereby supporting the local host defence.  相似文献   
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