65 research outputs found
Sintering Preparation of 15 wt% Cr Cast Iron as well as Its Mechanical Properties and Impact Abrasive Wear
15 wt% Cr sintered High Chromium Cast Iron (HCCI) with full density was successfully prepared by Super-solidus Liquid Phase Sintering (SPLS) technique, with water atomized 15 wt% Cr high chromium cast iron powder as initial materials. Its densification behavior and microstructure evolution in SPLS process and mechanical properties were investigated systematically. Additionally, the impact abrasive wear resistance under different impact energies were also analyzed and compared with another sintered HCCI with 20 wt% Cr. The results indicated that sintering temperature has a strong influence on the sintered alloy’s density, hardness, impact toughness and bending strength. The M7C3 type (M is Cr and Fe) carbides were obviously coarsened as temperature increased and their rod-shaped branches were fully developed at the same time, thereby resulting in carbide network formation in the matrix. The reasonable sintering temperature range was 1195–1205 °C, and the optimum mechanical properties had the hardness of 63.9 HRC, bending strength of 2112.65 MPa and impact toughness of 7.92 J/cm2. What is more important impact abrasive wear test results indicated 15 wt% Cr sintered HCCI’s wear resistance could be comparable to 20 wt% Cr sintered HCCI under impact energy 1~3 J/cm2, and it is more cost effective
Myasthenia gravis-like syndrome induced by expression of interferon gamma in the neuromuscular junction.
Abnormal humoral responses toward motor end plate constituents in muscle induce myasthenia gravis (MG). To study the etiology of this disease, and whether it could be induced by host defense molecules, we examined the consequences of interferon (IFN) gamma production within the neuromuscular junction of transgenic mice. The transgenic mice exhibited gradually increasing muscular weakness, flaccid paralysis, and functional disruption of the neuromuscular junction that was reversed after administration of an inhibitor of acetylcholinesterase, features which are strikingly similar to human MG. Furthermore, histological examination revealed infiltration of mononuclear cells and autoantibody deposition at motor end plates. Immunoprecipitation analysis indicated that a previously unidentified 87-kD target antigen was recognized by sera from transgenic mice and also by sera from the majority of human MG patients studied. These results suggest that expression of IFN-gamma at motor end plates provokes an autoimmune humoral response, similar to human MG, thus linking the expression of this factor with development of this disease
Molecular Subtypes of Oral Squamous Cell Carcinoma Based on Immunosuppression Genes Using a Deep Learning Approach
Background: The mechanisms through which immunosuppressed patients bear
increased risk and worse survival in oral squamous cell carcinoma (OSCC) are unclear.
Here, we used deep learning to investigate the genetic mechanisms underlying
immunosuppression in the survival of OSCC patients, especially from the aspect of
various survival-related subtypes.
Materials and methods: OSCC samples data were obtained from The Cancer
Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and OSCCrelated
genetic datasets with survival data in the National Center for Biotechnology
Information (NCBI). Immunosuppression genes (ISGs) were obtained from the HisgAtlas
and DisGeNET databases. Survival analyses were performed to identify the ISGs
with significant prognostic values in OSCC. A deep learning (DL)-based model
was established for robustly differentiating the survival subpopulations of OSCC
samples. In order to understand the characteristics of the different survival-risk
subtypes of OSCC samples, differential expression analysis and functional enrichment
analysis were performed.
Results: A total of 317 OSCC samples were divided into one inferring cohort (TCGA)
and four confirmation cohorts (ICGC set, GSE41613, GSE42743, and GSE75538).
Eleven ISGs (i.e., BGLAP, CALCA, CTLA4, CXCL8, FGFR3, HPRT1, IL22, ORMDL3,
TLR3, SPHK1, and INHBB) showed prognostic value in OSCC. The DL-based model
provided two optimal subgroups of TCGA-OSCC samples with significant differences
(p = 4.91E-22) and good model fitness [concordance index (C-index) = 0.77]. The DL
model was validated by using four external confirmation cohorts: ICGC cohort (n = 40,
C-index = 0.39), GSE41613 dataset (n = 97, C-index = 0.86), GSE42743 dataset
(n = 71, C-index = 0.87), and GSE75538 dataset (n = 14, C-index = 0.48). Importantly,
subtype Sub1 demonstrated a lower probability of survival and thus a more aggressive
nature compared with subtype Sub2. ISGs in subtype Sub1 were enriched in the tumorinfiltrating
immune cells-related pathways and cancer progression-related pathways,
while those in subtype Sub2 were enriched in the metabolism-related pathways.
Conclusion: The two survival subtypes of OSCC identified by deep learning can
benefit clinical practitioners to divide immunocompromised patients with oral cancer
into two subpopulations and give them target drugs and thus might be helpful for
improving the survival of these patients and providing novel therapeutic strategies in
the precision medicine area
Ethnic Differences in Body Composition and Obesity Related Risk Factors: Study in Chinese and White Males Living in China
The purpose of this cross-sectional observational study was to identify ethnic differences in body composition and obesity-related risk factors between Chinese and white males living in China. 115 Chinese and 114 white male pilots aged 28–63 years were recruited. Fasting body weight, height and blood pressure were measured following standard procedures. Whole-body and segmental body composition were measured using an 8-contact electrode bioimpedance analysis (BIA) system. Fasting serum glucose, fasting plasma total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and triglycerides (TG) were assessed using automatic biochemistry analyzer. After adjusting for age and body mass index (BMI), Chinese males had significantly higher percentage of body fat (PBF) both with respect to whole body (Chinese: 23.7%±0.2% vs. Whites: 22.4%±0.2%) and the trunk area (Chinese: 25.0%±0.3% vs. Whites: 23.2%±0.3%) compared to their white counterparts. At all BMIs, Chinese males had significantly higher fasting glucose levels (Chinese: 5.7±1.0 mmol/L vs. Whites: 5.2±1.0 mmol/L) but lower high-density lipoprotein levels (Chinese: 0.8±1.0 mmol/L vs. Whites: 1.0±1.0 mmol/L) than white males. In addition, a marginally significantly higher diastolic blood pressure was found among Chinese men than that among white men (Chinese: 80±1.0 mmHg vs. Whites: 77±1.0 mmHg). Chinese males had more body fat and a greater degree of central fat deposition pattern than that seen in white males in the present study. Furthermore, data on blood pressure, fasting glucose and blood lipids suggest that Chinese men may be more prone to obesity-related risk factors than white men
Hybrid Gene Origination Creates Human-Virus Chimeric Proteins during Infection
RNA viruses are a major human health threat. The life cycles of many highly pathogenic RNA viruses like influ-enza A virus (IAV) and Lassa virus depends on host mRNA, because viral polymerases cleave 50-m7G-cappedhost transcripts to prime viral mRNA synthesis (‘‘cap-snatching’’). We hypothesized that start codons withincap-snatched host transcripts could generate chimeric human-viral mRNAs with coding potential. We reportthe existence of this mechanism of gene origination, which we named ‘‘start-snatching.’’ Depending on thereading frame, start-snatching allows the translation of host and viral ‘‘untranslated regions’’ (UTRs) to createN-terminally extended viral proteins or entirely novel polypeptides by genetic overprinting. We show thatboth types of chimeric proteins are made in IAV-infected cells, generate T cell responses, and contributeto virulence. Our results indicate that during infection with IAV, and likely a multitude of other human, animaland plant viruses, a host-dependent mechanism allows the genesis of hybrid genes
Fixed and Variable Temperature Super-Solidus Liquid Phase Sintering of High Chromium Cast Iron with 25 Wt.%CR and Its Microstructure
A variable temperature super-solidus liquid phase sintering (SLPS) technique is employed in fabrication of high chromium cast iron (HCCI) with 25wt.%Cr to extend its sintering temperature window. Its microstructure evolution, mechanical properties, and abrasive wear behavior are investigated systemically. The results indicate that the variable temperature SLPS can obtain samples with full density plus fine and uniformly distributed carbide particles, and its carbide volume fraction is increased by 4~5% in comparison with the fixed temperature SLPSed one. Meanwhile, its bending strength and impact toughness can be raised by 8.0% and 16.7%, respectively. Finally, the sintering temperature window for variable temperature SLPS of HCCI is extended by 12 °C, reaching 27 °C
Solid-phase PCR based on thermostable, encoded magnetic microspheres for simple, highly sensitive and multiplexed nucleic acid detection
Ultrasound-guided serratus anterior plane block versus paravertebral block on postoperation analgesia and safety following the video-assisted thoracic surgery: A prospective, randomized, double-blinded non-inferiority clinical trial
Summary: Background: Both the anesthetic efficacy of ultrasound-guided serrate anterior plane block (SAPB) and the ultrasound-guided paravertebral block (PVB) in alleviating postoperative pain have been well concerned. This study primarily aims to evaluate whether the ultrasound-guided SAPB and ultrasound-guided PVB can provide comparable analgesia for video-assisted thoracic surgery. Secondarily, the safety and clinical satisfaction of the two blocks are evaluated. Methods: It was a prospective, randomized, double-blinded non-inferiority clinical trial involving 99 patients with lung nodules receiving video-assisted thoracic surgery with ultrasound-guided SAPB or PVB on T4 and T7 vertebra using 0.375% ropivacaine at 3 mg/kg. The Visual Analogue Scale (VAS) scores at rest and cough at 24 h/48 h postoperatively and the incidence and severity of chronic pain at 3 and 6 months postoperatively were the primary outcome. Secondary outcomes included the complications and block application time of two kinds of blocks, and consumption of sufentanil as an analgesic rescue. Results: A total of 92 eligible patients were recruited, including 46 in the SAPB group and 46 in the PVB group. No significant differences in VAS scores at rest and cough at first 48 h, 3 months, and 6 months postoperatively between the SAPB group and PVB group were detected (all P > 0.05). The SAPB group had fewer complications and higher patient satisfaction(P<0.05). Conclusion: The ultrasound-guided SAPB was not inferior to PVB in alleviating postoperative pain following the VATS with fewer complications and higher patient satisfaction
Influence of Clones on Relationship between Natural Rubber and Size of Rubber Particles in Latex
IAN873, Dongfang93114 and Reyan73397, created through vegetative propagation for their high yield and excellent cold resistance, are major clones planted in China. In this work, latexes with rubber particles of the same size from these clones are separated from fresh natural rubber latex, and corresponding rubber films are prepared from each latex. The structure and components of each film are measured. This indicates that the characteristics of the rubbers obtained from latexes with similar particle sizes show some resembling trends among different clones, while for specific samples, those characteristics vary depending on the clone. The molecular weight is generally highest in IAN873 and lowest in Reyan73397. Rubber chains in small rubber particles are longer, and large rubber particles show a wider molecular weight distribution. The gel content of every sample from Reyan73397 is lower than the other two clones. The nitrogen content increases with the size of rubber particles in all clones. The ester content of small rubber particles in IAN873 and Reyan73397 is almost zero. Large rubber particles have more branching points formed via esters. This study provides a new perspective on the influence of clones on the relationship between characteristics of natural rubber and the size of rubber particles in natural rubber latex
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