The association of COVID-19 with diffuse large B-cell lymphoma: a Mendelian randomization study.

With the outbreak of coronavirus disease 2019 (COVID-19), there has been an increasing focus on exploring the relationship between SARS-CoV-2 infection and tumors. However, there is no consensus on the association between COVID-19 and lymphoma. In this study, genome-wide association study (GWAS) summary data sets for COVID-19 and lymphoma were obtained from the OPEN GWAS website. Single nucleotide polymorphisms (SNPs) were selected as genetic instrument variants for fulling P < 5 × 10-8 and linkage disequilibrium [LD] r2 < 0.001. Both palindromic and outlier SNPs were removed. Cochran's Q test, the MR‒Egger intercept test, and leave-one-out analysis were employed to assess the sensitivity of the effect of COVID-19 on lymphoma. The results showed that COVID-19 patients with very severe respiratory symptoms have an increased risk of developing diffuse large B-cell lymphoma (IVW, OR = 1.765, 95% CI 1.174-2.651, P = 0.006). There was no association between COVID-19 with very severe respiratory symptoms and Hodgkin's lymphoma or other types of non-Hodgkin's lymphoma. No horizontal or directional pleiotropy was observed in the Mendelian randomization analysis. In conclusion, SARS-CoV-2 infection with very severe respiratory symptoms may be a potential risk factor for diffuse large B-cell lymphoma (DLBCL), and follow-up studies with larger samples are needed.

The causal effect of inflammatory bowel disease on diffuse large B-cell lymphoma: two-sample Mendelian randomization study.

Background: It has been reported that inflammatory bowel disease (IBD) is associated with an increased risk of malignancies, including lymphoma. A number of large observational studies have been devoted to exploring the causal link between IBD and malignant lymphoma. However, no consensus exists on whether there is a causal relationship between IBD and malignant lymphoma. Methods: The summary dataset of the IBD and lymphoma genome-wide association studies (GWAS) was obtained from the OPEN GWAS website. Single-nucleotide polymorphisms (SNPs) were selected as genetic instrumental variants (IVs) for fulling P < 5 × 10-8 and linkage disequilibrium (LD) of r2 = 0.001 in the IBD GWAS. The proxy SNPs with LD of r2 > 0.8 were identified. Palindromic SNPs and outlier SNPs were excluded. The assessments of sensitivity employed the Cochran's Q test, Mendelian randomization (MR)-Egger intercept test, and leave-one-out analysis. Results: The MR analysis results proved the causality of IBD on diffuse large B-cell lymphoma (DLBCL). The risk of developing DLBCL is increased by 28.6% in patients with IBD [odds ratio (OR)IVW = 1.286, 95% confidence interval (CI) 1.066-1.552, P = 0.009]. The results of the subgroup analysis showed that Crohn's disease (ORIVW = 1.218, 95% CI 1.030-1.441, P = 0.021) rather than ulcerative colitis (ORIVW = 1.206, 95% CI 0.984-1.478, P = 0.072) had a causal effect on DLBCL. No horizontal and directional pleiotropy was observed in the MR studies. Conclusions: The above MR study concluded that IBD itself is causally responsible for DLBCL, especially Crohn's disease. Further investigations are needed to elucidate the mechanism underlying this direct causal link.

The prognostic role of lymphocyte to monocyte ratio (LMR) in patients with Myelodysplastic Neoplasms.

BACKGROUND: Previous studies validated the prognostic significance of lymphocyte to monocyte ratio (LMR) in patients with solid tumors and some hematologic malignancies. However, the correlation between LMR and Myelodysplastic Neoplasms (MDS) was unclear. The study intends to investigate the prognostic impact of LMR on MDS patients. METHODS: 91 newly diagnosed MDS patients were included in this retrospective study. The cut-off of LMR was 3.2 by X-Tile. All patients were divided into the low LMR group (<3.2) and the high LMR group (≥3.2). Clinical characteristics were compared between the two groups. RESULTS: Patients in the high LMR group (n = 67) had better OS (P = 0.007) from the Kaplan-Meier survival curves. The results of the univariate analysis demonstrated that LMR was a prognostic factor for OS [hazard ratio (HR) = 2.070, 95%CI 1.201-3.571, P = 0.009]. After multivariate cox analysis, low LMR was confirmed to be an independent predictor of poor OS in MDS patients (HR = 1.872, 95%CI 1.084-3.230, P = 0.024). CONCLUSIONS: LMR, a representative marker of systematic inflammation and immune response, has potential prognostic significance in MDS patients.

Prognostic impact of the controlling nutritional status score in patients with hematologic malignancies: A systematic review and meta-analysis.

Background: An increasing number of studies have validated the prognostic significance of the controlling nutritional status (CONUT) score in patients with solid tumors. However, the extent of the correlation between the CONUT score and clinical outcomes of patients with hematologic malignancies is unclear. Objective: This study aimed to investigate the prognostic role of the CONUT score in patients with hematologic malignancies. Methods: All relevant articles published up to November 15, 2021, were identified by systematically searching PubMed, Embase, Web of Science, and Cochrane Library. Pooled hazard ratios (HRs) and 95% confidence intervals were used to quantitatively analyze the association between the CONUT scores and clinical outcomes of patients with hematologic malignancies. Subgroup and sensitivity analyses were performed. Funnel plots as well as Begg's and Egger's tests were used to assess publication bias. Results: Six studies with 1811 patients were included in the meta-analysis. The results showed that a high CONUT score was associated with worse overall survival (OS) (HR=1.34, 95%CI 1.14-1.59, P < 0.001) and progression-free survival (PFS) (HR=1.20, 95%CI 1.10-1.32, P < 0.001). Conclusions: The CONUT score is an independent prognostic factor in patients with hematologic malignancies. Systematic review registration: http://www.crd.york.ac.uk/prospero/, identifier CRD42021292621.

Prognostic role of controlling nutritional status score in hematological malignancies.

BACKGROUND: Controlling nutritional status (CONUT) score, based on three indexes including serum albumin (ALB), total cholesterol (CHO), and absolute lymphocyte count (ALC), has been closely associated with the prognosis of cancer patients. Multiple studies revealed the significance of CONUT score in hematological malignancies, including diffuse large B-cell lymphoma (DLBCL), peripheral T-cell lymphoma (PTCL), multiple myeloma (MM), and leukemia. OBJECTIVE: This review aimed to explore the prognostic role of CONUT score in hematological malignancies. METHODS: We conducted this review through Pubmed to summarize the published studies on the CONUT score in hematological malignancies, using the terms: Controlling nutritional status, CONUT score, hematological malignancy, lymphoma, multiple myeloma, and leukemia. RESULT: CONUT score can reflect not only the nutritional status but also the inflammatory status of patients with hematological malignancies. It can assist in predicting the survival of patients with DLBCL, PTCL, MM, adult T-cell leukemia (ATL), myelodysplastic syndrome (MDS), and acute myeloid leukemia with myelodysplasia related changes (AML-MRC). CONCLUSION: CONUT score plays an important role in predicting the prognosis of patients with hematological malignancies.

Microstructural Evolution and Mechanical Evaluation of a Laser-Induced Composite Coating on a Ni-Based Superalloy during Thermal Exposure.

A Ni-17Mo-7Cr-based superalloy was laser surface-modified to improve its tribological properties. Si particles were employed as coating materials. Si melted on the surface of the alloy during the process, triggering the formation of Mo6Ni6C carbides and Ni-Si intermetallics. A defect-free coating obtained was mostly made up of primary Mo6Ni6C and γ-Ni31Si12, as well as a eutectic structure of ß1-Ni3Si and α-Ni-based solid solution (α-Ni (s.s)). The volume fraction of hard reinforcements (Mo6Ni6C, γ-Ni31Si12, and ß1-Ni3Si) reached up to 85% in the coating. High-temperature microstructural stability of the coating was investigated by aging the coating at 1073 K for 240-480 h, to reveal its microstructural evolution. In addition, the mechanical performance of the coating was investigated. The nanoscale elastic modulus and hardness of Mo6Ni6C, γ-Ni31Si12, and α-Ni (s.s) were characterized using the nanoindentation tests. The nanoscratch tests were performed to measure the local wear resistance of the coating. Lastly, the Vickers hardness distribution across the cross-section of the coating before and after thermal exposure was compared. The work performed provides basic information understanding the microstructural evolution and mechanical performance of laser-induced coatings on Ni-based superalloys.

Microstructure and Mechanical Properties of 34CrMo4 Steel for Gas Cylinders Formed by Hot Drawing and Flow Forming.

An integral manufacturing process with hot drawing and cold flow forming was proposed for large-diameter seamless steel gas cylinders. The main purpose of this study was to find out the effects of the manufacturing process on the microstructure and mechanical properties of gas cylinders made of 34CrMo4 steel. Two preformed cylinders were produced by hot drawing. One cylinder was then further manufactured by cold flow forming. The experiments were carried out using three types of material sample, namely, base material (BM), hot drawing cylinder (HD), and cold flow-formed cylinder (CF). Tensile and impact tests were performed to examine the mechanical properties of the cylinders in longitudinal and transverse directions. Microstructure evolution was analyzed by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) to reveal the relation between the mechanical properties and the microstructure of the material. It is found that the mechanical properties of the 34CrMo4 steel gas cylinders were significantly improved after hot drawing and flow forming plus a designed heat treatment, compared with the base material. The observations of microstructure features such as grain size, subgrain boundaries, and residual strain support the increase in mechanical properties due to the proposed manufacturing process.

Characterization of SiC Ceramic Joints Brazed Using Au⁻Ni⁻Pd⁻Ti High-Temperature Filler Alloy.

In this work, (Au79Ni17Pd4)96Ti4 (wt.%) filler alloy was designed and employed to join SiC ceramics. The effects of brazing temperature and soaking time on the microstructure and fracture morphology of joints were investigated. The results show that the joint obtained can be described as SiC/reaction layer/braze/reaction layer/SiC. The reaction layer was composed of TiC and Au (Si, Ti). The wettability of the filler alloy toward the SiC ceramics was analyzed. The braze zone was mainly constituted by Pd2Si, Ni2Si, and Au (Ni, Si). A large number of nano-sized TiC particles were distributed within the Au (Ni, Si) layer. The formation mechanism of the braze containing different phases was discussed. The brazing temperature and soaking time had a significant effect on the reaction layer at the SiC/braze interface and TiC particles within the Au (Ni, Si) layer, while they showed a negligible effect on the Pd2Si and Ni2Si within the braze. The inherent reason was also clarified in detail. The joint fractography indicated that a good bonding was achieved between the filler alloy and SiC, while joint fracture was primarily induced by the thermal stresses residing after the brazing cycle.