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111.
New treatments are required for rituximab-refractory follicular lymphoma (FL). In the present study, patients with rituximab-refractory FL received 8 weekly infusions of ofatumumab (CD20 mAb; dose 1, 300 mg and doses 2-8, 500 or 1000 mg; N = 116). The median age of these patients was 61 years, 47% had high-risk Follicular Lymphoma International Prognostic Index scores, 65% were chemotherapy-refractory, and the median number of prior therapies was 4. The overall response rate was 13% and 10% for the 500-mg and 1000-mg arms, respectively. Among 27 patients refractory to rituximab monotherapy, the overall response rate was 22%. The median progression-free survival was 5.8 months. Forty-six percent of patients demonstrated tumor reduction 3 months after therapy initiation, and the median progression-free survival for these patients was 9.1 months. The most common adverse events included infections, rash, urticaria, fatigue, and pruritus. Three patients experienced grade 3 infusion-related reactions, none of which were considered serious events. Grade 3-4 neutropenia, leukopenia, anemia, and thrombocytopenia occurred in a subset of patients. Ofatumumab was well tolerated and modestly active in this heavily pretreated, rituximab-refractory population and is therefore now being studied in less refractory FL and in combination with other agents in various B-cell neoplasms. The present study was registered at www.clinicaltrials.gov as NCT00394836.  相似文献   
112.
There is evidence suggesting that N-cadherin expression on osteoblast lineage cells regulates hematopoietic stem cell (HSC) function and quiescence. To test this hypothesis, we conditionally deleted N-cadherin (Cdh2) in osteoblasts using Cdh2(flox/flox) Osx-Cre mice. N-cadherin expression was efficiently ablated in osteoblast lineage cells as assessed by mRNA expression and immunostaining of bone sections. Basal hematopoiesis is normal in these mice. In particular, HSC number, cell cycle status, long-term repopulating activity, and self-renewal capacity were normal. Moreover, engraftment of wild-type cells into N-cadherin-deleted recipients was normal. Finally, these mice responded normally to G-CSF, a stimulus that mobilizes HSCs by inducing alterations to the stromal micro-environment. In conclusion, N-cadherin expression in osteoblast lineage cells is dispensable for HSC maintenance in mice.  相似文献   
113.
AML1-ETO (AE) is a fusion product of translocation (8;21) that accounts for 40% of M2 type acute myeloid leukemia (AML). In addition to its role in promoting preleukemic hematopoietic cell self-renewal, AE represses DNA repair genes, which leads to DNA damage and increased mutation frequency. Although this latter function may promote leukemogenesis, concurrent p53 activation also leads to an increased baseline apoptotic rate. It is unclear how AE expression is able to counterbalance this intrinsic apoptotic conditioning by p53 to promote survival and self-renewal. In this report, we show that Bcl-xL is up-regulated in AE cells and plays an essential role in their survival and self-renewal. Further investigation revealed that Bcl-xL expression is regulated by thrombopoietin (THPO)/MPL-signaling induced by AE expression. THPO/MPL-signaling also controls cell cycle reentry and mediates AE-induced self-renewal. Analysis of primary AML patient samples revealed a correlation between MPL and Bcl-xL expression specifically in t(8;21) blasts. Taken together, we propose that survival signaling through Bcl-xL is a critical and intrinsic component of a broader self-renewal signaling pathway downstream of AML1-ETO-induced MPL.  相似文献   
114.

Purpose

Interleukin-4 (IL-4) and interleukin-13 (IL-13) are anti-inflammatory and immunomodulatory cytokines which can influence cancer-directed immunosurveillance. Nothing is presently known about expression of these cytokines and their receptors (IL-4R and IL-13R) in colorectal cancer. The aim of this study was to characterize their expression in primary colorectal cancer specimens and to evaluate possible functions for this disease.

Methods

Expression of IL-4, IL-13, IL-4R, and IL-13R protein was characterized by immunohistochemistry in 359 patients with Union for International Cancer Control stage I–III colorectal cancer and evaluated by uni- and multivariate analysis for their prognostic relevance.

Results

All four proteins were expressed in colorectal cancer specimens. In the cancer cells, high IL-4, IL-13, IL-4R, and IL-13R immunoreactivity were present in 33 % (118/359), 50 % (181/359), 36 % (129/359), and 42 % (152/359), respectively. Patients with high expression of IL-4, IL-4R, and IL-13R had a lower frequency of lymph node metastases. Expression of IL-13 did not influence the frequency of lymph node metastases. However, high IL-13-immunoreactivity was associated with a better overall survival (p?=?0.041). Expression of IL-4, IL-4R, or IL-13R did not influence survival. Multivariate analysis revealed that besides pT classification and tumor recurrence, IL-13 expression was an independent prognostic factor for overall survival.

Conclusions

Expression of IL-4, IL-4R, and IL-13R are involved in the process of local metastases in colorectal cancer, while IL-13 expression has an impact on survival. These interleukins and their receptors may become attractive targets for the treatment of colorectal cancer.  相似文献   
115.
116.

Background

Chemotherapy has in some series been linked with increased morbidity after a hepatectomy. Hepatic injuries may result from the treatment with chemotherapy, but can also be secondary to co-morbid diseases. The aim of the present study was to draw correlations between clinical features, treatment with chemotherapy and injury phenotypes and assess the impact of each upon perioperative morbidity.

Patients and methods

Retrospective samples (n = 232) were scored grading steatosis, steatohepatitis and sinusoidal injury (SI). Clinical data were retrieved from medical records. Correlations were drawn between injury, clinical features and perioperative morbidity.

Results

Injury rates were 18%, 4% and 19% for steatosis, steatohepatitis and SI, respectively. High-grade steatosis was more common in patients with diabetes [odds ratio (OR) = 3.33, P = 0.01] and patients with a higher weight (OR/kg = 1.04, P = 0.02). Steatohepatitis was increased with metabolic syndrome (OR = 5.88, P = 0.02). Chemotherapy overall demonstrated a trend towards an approximately doubled risk of high-grade steatosis and steatohepatitis although not affecting SI. However, pre-operative chemotherapy was associated with an increased SI (OR = 2.18, P = 0.05). Operative morbidity was not increased with chemotherapy, but was increased with steatosis (OR = 2.38, P = 0.02).

Conclusions

Diabetes and higher weight significantly increased the risk of steatosis, whereas metabolic syndrome significantly increased risk of steatohepatitis. The presence of high-grade steatosis increases perioperative morbidity, not administration of chemotherapy per se.  相似文献   
117.
118.
In this randomized controlled clinical trial, the authors evaluated the effectiveness of cognitive processing therapy (CPT) in the treatment of self‐reported and clinician‐assessed posttraumatic stress disorder (PTSD) related to military sexual trauma (MST), along with depressive symptoms. Eighty‐six veterans (73 female, 13 male) randomly assigned to receive 12 individual sessions of either CPT or present‐centered therapy (PCT) were included in analyses. Blinded assessments occurred at baseline, posttreatment, and 2, 4, and 6 months posttreatment. Mixed‐effects model analysis revealed a significant interaction between groups (p = .05, d = ?0.85): At posttreatment, veterans who received CPT had a significantly greater reduction in self‐reported, but not clinician‐assessed, PTSD symptom severity compared to veterans who received PCT. All three primary outcome measures improved significantly, both clinically and statistically, across time in both treatment groups. Pre‐ and posttreatment effect sizes were mostly moderate to large (d = 0.30–1.02) and trended larger in the CPT group. Although the study was impacted by treatment fidelity issues, results provide preliminary evidence for the effectiveness of CPT in reducing self‐reported PTSD symptoms in a population of veterans with MST, expanding on established literature that has demonstrated the effectiveness of CPT in treating PTSD related to sexual assault in civilian populations.  相似文献   
119.
The primary goal of this study was to assess peripheral bone microarchitecture and strength in postmenopausal women with type 2 diabetes with fragility fractures (DMFx) and to compare them with postmenopausal women with type 2 diabetics without fractures (DM). Secondary goals were to assess differences in nondiabetic postmenopausal women with fragility fractures (Fx) and nondiabetic postmenopausal women without fragility fractures (Co), and in DM and Co women. Eighty women (mean age 61.3 ± 5.7 years) were recruited into these four groups (DMFx, DM, Fx, and Co; n = 20 per group). Participants underwent dual‐energy X‐ray absorptiometry (DXA) and high‐resolution peripheral quantitative computed tomography (HR‐pQCT) of the ultradistal and distal radius and tibia. In the HR‐pQCT images volumetric bone mineral density and cortical and trabecular structure measures, including cortical porosity, were calculated. Bone strength was estimated using micro–finite element analysis (µFEA). Differential strength estimates were obtained with and without open cortical pores. At the ultradistal and distal tibia, DMFx had greater intracortical pore volume (+52.6%, p = 0.009; +95.4%, p = 0.020), relative porosity (+58.1%, p = 0.005; +87.9%, p = 0.011) and endocortical bone surface (+10.9%, p = 0.031; +11.5%, p = 0.019) than DM. At the distal radius DMFx had 4.7‐fold greater relative porosity (p < 0.0001) than DM. At the ultradistal radius, intracortical pore volume was significantly higher in DMFx than DM (+67.8%, p = 0.018). DMFx also displayed larger trabecular heterogeneity (ultradistal radius: +36.8%, p = 0.035), and lower total and cortical BMD (ultradistal tibia: ?12.6%, p = 0.031; ?6.8%, p = 0.011) than DM. DMFx exhibited significantly higher pore‐related deficits in stiffness, failure load, and cortical load fraction at the ultradistal and distal tibia, and the distal radius than DM. Comparing nondiabetic Fx and Co, we only found a nonsignificant trend with increase in pore volume (+38.9%, p = 0.060) at the ultradistal radius. The results of our study suggest that severe deficits in cortical bone quality are responsible for fragility fractures in postmenopausal diabetic women. © 2013 American Society for Bone and Mineral Research  相似文献   
120.
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