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During the construction and application of underground engineering, rock materials are often subjected to cyclic loads with varying amplitudes. Although the mechanical properties of rock materials under cyclic loading have been extensively studied, the gradual process of internal crack propagation still needs further exploration and quantitative description. In this paper, the failure process of rock under monotonic loading and cyclic loading was analysed from macroscopic and microscopic perspectives using laboratory experiments and numerical simulations. Triaxial experiments and cyclic loading experiments with variable amplitudes were conducted on marble specimens under different confining pressures. Then, the experimental process was reproduced by numerical simulation using the discrete element method, and the process of rock failure was described quantitatively by defining the contact failure rate and damage density. In addition, the relationship between dissipated energy and crack propagation is discussed to some extent. The results show that based on the evolutions of the contact failure rate and damage density, the monotonic loading process can be more accurately divided into four stages. During the accelerating crack propagation stage, the cyclic load will generate more failure contacts beyond the direction of 70° to 110°, forming diffuse cracks and ultimately resulting in a bulging failure mode. The higher the confining pressure is, the greater the impact. The increment of the damage density is exponentially proportional to the increase in the cyclic stress amplitude ratio, while the relationship between the confining pressure condition coefficient and confining pressure follows a power function. [ABSTRACT FROM AUTHOR]

The IL-2/IL-2 receptor (IL-2R) system plays a central role in maintaining normal T cell immunity, and its disturbance is associated with several hematologic disorders. Studies have found in several types of lymphoma that abnormal amounts of soluble IL-2R (sIL-2R) may result in imbalance of the IL-2/IL-2R system and hence of the T cell immunoregulation. Whether the level of sIL-2R in blood could predict treatment outcomes or not needs to be investigated in multiple myeloma (MM) patients. The level of sIL-2R in serum was measured using enzyme-linked immunosorbent assay (ELISA) in 81 patients with newly diagnosed MM. Twenty-six patients (32.1%) were treated with bortezomib-based regimens and 55patients (67.9%) received old drugs-based regimens. The mean concentration of sIL-2R for myeloma patients was 8.51 ng/ml, significantly higher than that of healthy controls (0.56 ng/ml, p < 0.0001). The best cutoff value for sIL-2R in predicting high risk for disease progression is 6.049 ng/ml with an area under curve (AUC) of 0.665 (p = 0.013). Thirty-six patients (44.4%) were classified as higher sIL-2R level group (> 6.049 ng/ml), and 45 patients (55.6%) as lower group (≤ 6.049 ng/ml). The overall response rate (ORR) was 60.0% in lower sIL-2R level group, and 41.7% in higher level group (p = 0.156). The median progression-free survival (PFS) and overall survival (OS) was 12 months (range, 2.0-65 months) and 20 months (range, 2.0-118 months), respectively. In a multivariate survival analysis, including Eastern Cooperative Oncology Group performance status score, treatment response, and sIL-2R level, it was found that all these three parameters were significantly independent prognostic factors for PFS (p = 0.032, 0.016, and 0.043, respectively), but none factors maintained their value in predicting OS. Subgroup analysis revealed that high level of sIL-2R is correlated with significantly inferior PFS in patients treated with bortezomib-based regimens (p = 0.004). Serum sIL-2R level is an independent prognostic factor for PFS, indicating novel drugs targeting the imbalance of IL-2/IL-2R system may be a promising strategy in MM. [ABSTRACT FROM AUTHOR]

Background: Interleukin-10 (IL-10) is a inhibiting inflammatory cytokine that plays an important role in immune suppressive microenvironment in multiple myeloma (MM). Whether the level of serum IL-10 could predict treatment response and survival outcomes or not needs to be investigated in MM patients. Methods: The level of IL-10 in serum was measured using enzyme-linked immunosorbent assay in 188 patients with newly diagnosed MM. Results: The best cutoff value for IL-10 in predicting survival is 169.69 pg ml(-1) with an area under the curve (AUC) value of 0.747 (P<0.001). In all, 92 patients (48.9%) were classified as high-IL-10 group (>169.96 pg ml(-1)) and 96 patients (51.1%) as low-IL-10 group (⩽169.96 pg ml(-1)). The overall response rate (ORR) was 79.2% in low-IL-10 group, significantly higher than that in high-IL-10 group (53.3%, P<0.001). Patients in low-IL-10 group had significantly better survival compared with those in high-IL-10 group (3-year PFS rate: 69.3% vs 13.3%, P<0.001; 3-year OS rate: 93.6% vs 51.9%, P<0.001). Multivariate analysis revealed that serum IL-10 level >169.96 pg ml(-1) at diagnosis and certain cytogenetic abnormalities were two adverse factors for PFS and OS. Conclusions: Our data suggest that serum IL-10 at diagnosis is a novel, powerful predictor of prognosis for MM. [ABSTRACT FROM AUTHOR]

Patients with stage IE/IIE natural killer T (NK/T) cell lymphomas have discrepant survival outcome. This study aims to establish a prognostic model based on the pretreatment platelet lymphocyte ratio (PLR) specifically for localized extranodal NK/T cell lymphoma to guide the therapy. We retrospectively analyzed the data of 252 patients with early-stage upper aerodigestive tract NK/T cell lymphoma. The 5-year overall survival rate in 252 patients was 67.1 %. Prognostic factors for survival were female ( P = 0.025; relative risk, 0.51; 95 % CI 0.28-0.92), older age ( P = 0.000; relative risk, 3.34; 95 % CI 1.94-5.75), stage II( P = 0.020; relative risk, 1.79; 95 % CI 1.10-2.91), lactate dehydrogenase (LDH) level ( P = 0.009; relative risk, 2.00; 95 % CI 1.19-3.35), and PLR ( P = 0.020; relative risk, 1.77; 95 % CI 1.10-2.87). Based on these five parameters, we identified three different risk groups: group 1(106 cases, 43.4 %), no or one adverse factor; group 2(85 cases, 34.8 %), two factors; group 3(53 cases, 21.7 %), three to five factors. Five-year overall survival was 83.3 % for group 1, 62.2 % for group 2, and 43.1 % for group 3 ( P = 0.000). Compared with International Prognostic Index and Korean Prognostic Index, the new model has a better prognostic discrimination for the patients of stage IE/IIE upper aerodigestive tract NK/T cell lymphoma. The PLR-based prognosis model is useful to stratify patients with localized extranodal NK/T cell lymphoma into different risk groups and guide the treatment modalities selection. [ABSTRACT FROM AUTHOR]

Inflammation has been demonstrated to be widely involved in the carcinogenesis of nasopharyngeal carcinoma (NPC). However, the prognostic significance of lymphocyte to monocyte ratio (LMR) in metastatic NPC is not fully addressed. The purpose of the study is to investigate the prognostic impact of pre-treatment absolute lymphocyte count (ALC), absolute monocyte count (AMC), and LMR on patients with newly diagnosed metastatic NPC undergoing chemotherapy. Between January 2006 and December 2010, patients with newly diagnosed metastatic NPC undergoing chemotherapy were retrospectively collected. The prognostic significance of baseline clinical features and inflammatory markers was investigated. A total of 256 patients were eligible for the study. The best cut-off value of ALC, AMC, and LMR was 2.25 × 10/L, 0.35 × 10/L, and 5.07, respectively. Patients in the high LMR group had a significantly longer overall survival (OS) (25.0 months [24.50-25.49]) than patients in the low LMR group (16.0 months [15.51-16.49]; p < 0.001). In addition, ALC ≥ 2.25 × 10/L (HR, 0.59; 95 % CI, 0.43-0.81; p = 0.001) and LMR ≥5.07 (HR, 0.42; 95 % CI, 0.30-0.59; p < 0.001) remained as independent prognostic factors for superior OS, while AMC did not retained its prognostic significance in COX multivariate analysis. Pre-treatment ALC and LMR were demonstrated to be independent prognostic factors in patient with newly diagnosed metastatic NPC receiving chemotherapy. Future prospective studies are needed to validate the findings. [ABSTRACT FROM AUTHOR]

The association of prolonged rituximab therapy and hepatitis B virus (HBV) reactivation in diffuse large B-cell lymphoma (DLBCL) and the role of lamivudine prophylaxis remain undefined. The prevalence and mortality of HBV reactivation in HBsAg-positive patients with DLBCL undergoing rituximab-based treatment, who received prophylactic treatment with or without lamivudine, were retrospectively analyzed. From January 2003 to December 2009, there were 50 patients enrolled in the study, among of which 30 received the prophylactic treatment of lamivudine and 20 without prophylactic treatment of lamivudine. Among of the 50 patients, seven patients received further rituximab maintenance, once every 3 months for 2 years. Compared with lamivudine treatment group, it showed that there was significantly higher prevalence of HBV reactivation (60.0% vs 13.3%, P = .001), severe hepatitis (45.0% vs 6.7%, P = .004), and mortality (25.0% vs 3.3%, P = .032) in non-lamivudine prophylactic group; however, there was no statistically significant difference in the HBV DNA levels at reactivation (3.94 × 10 vs 8.30 × 10 copies/ml, P = .47) and the time from first dose of rituximab to HBV reactivation(207 vs 386 days, P = .28). For patients undergoing further rituximab maintanence treatment, the prevalence and mortality of HBV reactivation were 71.4 and 28.6%, respectively. The prevalence and mortality of HBV reactivation are 66.7% vs 75.0% ( P = 1.00) and 0 vs 50.0% ( P = .43) in lamivudine prophylactic and non-lamivudine prophylactic groups, respectively. The effect of lamivudine prophylaxis on preventing HBV reactivation was found to be less in patients undergoing longer duration of rituximab treatment. A longer duration of rituximab treatment contributed to higher morbidity and mortality of HBV reactivation in HbsAg-positive patients with DLBCL. Further study is warranted for the optimal management of hepatitis caused by HBV reactivation [ABSTRACT FROM AUTHOR]

Patients with newly diagnosed acute lymphoblastic leukemia (ALL) at a single institution were analyzed retrospectively. From 2006 to 2010, 47 patients were treated using the MRC UKALLXII/ECOG E2993 protocol. Prior to July 2005, 40 patients had been treated with the JALSG ALL 87 protocol. A complete remission (CR) rate of 91.5% was achieved with the E2993 protocol, which was not significantly higher than the 80% achieved using JALSG (P > 0.05). The median duration of CR in months was 19 for all patients treated with the MRC UKALLXII/ECOG E2993 protocol. Ph+ patients showed a median CR duration of 11.5 months, while Ph- patients had a significantly longer CR duration of 19 months (P = 0.019). Further, Ph- patients at standard risk (stratified on the basis of age and white blood cell count at diagnosis) had a CR duration of 21 months, which was significantly longer than the 12-month CR duration for the ten Ph- patients at high risk (P = 0.001). Significant differences were found in the 2-year event-free survival and overall survival rates between the MRC UKALLXII/ECOG E2993 and JALSG ALL 87 groups in the following three cohorts: all patients (P = 0.009 and 0.022, respectively), Ph- patients (P = 0.009 and 0.018, respectively), and standard-risk patients (P = 0.014 and 0.007, respectively). The overall mortality rate for induction therapy in the MRC UKALLXII/ECOG E2993 group was 2.1% (1 of 47 patients). One or more instances of grade IV myelosuppression occurred during induction therapy. Among the non-hematological toxicities, alopecia and elevated ALT and AST levels were the most common. The levels of ALT and AST could be reduced to less than twofold the normal values within 1-2 weeks. The data indicate that the MRC UKALLXII/ECOG E2993 regimen is well tolerated in Chinese adults with ALL and can improve survival compared with the JALSG ALL 87 protocol. Risk stratification at diagnosis based on age and WBC count is suitable for adults with ALL, and it is necessary to adopt different strategies as determined by diagnostic results. Lastly, Ph+ patients have an extremely poor prognosis. [ABSTRACT FROM AUTHOR]