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The objective of this study was to investigate the possible association between the single nucleotide polymorphism (SNP), rs35569394, of the vascular endothelial growth factor gene (VEGF) and the risk of esophageal cancer (EC) in the Han Chinese population. A total of 290 EC subjects and 322 ethnically matched unrelated healthy controls free from the esophageal disease were studied. Genomic DNA was isolated from peripheral blood by salting out. Genotyping of VEGF rs35569394 polymorphism was carried out via polymerase chain reaction followed by agarose gel electrophoresis. The results showed that the distribution of genotypes was significantly different across the gender groups (p=0.032) and clinical stages (p=0.034). VEGF rs35569394 was associated with EC risk (p= 0.012, OR=1.34). A gender analysis break-down showed that rs35569394-D allele frequency was significantly higher in females than in the controls (p=0.0004, OR=1.81). Moreover, significant associations were also found in females under the dominant model (II versus ID+DD: χ2=8.18, p=0.003, OR=2.12) and the recessive model (II+ID versus DD: χ2=8.25, p=0.004, OR=2.39). Additionally, we found that the genotype, rs35569394-DD, was associated with a complete response + partial response to chemotherapy when compared with rs35569394-II (χ2=4.67, p=0.030, OR=0.47). In conclusion, our case-control study showed that the VEGF rs35569394 was significantly associated with the clinical stages and the increased risk of EC in Han Chinese females. In addition, the genotype rs35569394-DD showed a better response to chemotherapy.

Purpose: To investigate the effects of dose reduction on image quality and lesion detectability of oncological 18F-FDG total-body PET/CT in paediatric oncological patients, and explore the minimum threshold of administered tracer activity.Methods: A total of 33 paediatric patients (weight, 8.5–58.5 kg; age 0.8–17.6 years) underwent total-body PET/CT using uEXPLORER scanner with an 18F-FDG administered dose of 3.7 MBq/kg and an acquisition time of 600 s were retrospectively enrolled. Low-dose images (0.12 – 1.85 MBq/kg) were simulated by truncating the list-mode PET data to reducing count density. Subjective image quality was rated on a 5-point scale. Semi-quantitative uptake metrics for low-dose images were assessed using region-of-interest (ROI) analysis of healthy liver and suspected lesions and were compared to full-dose images. The micro-lesion detectability was compared among the dose-dependent PET images.Results: Our analysis shows that sufficient subjective image quality and lesion conspicuity could be maintained down to 1/30th (0.12 MBq/kg) of the administered dose of 18F-FDG, where good image quality scores were given to 1/2- and 1/10- dose groups. The image noise was significantly more deranged than the overall quality and lesion conspicuity in 1/30- to 1/10-dose groups (all P < 0.05). With reduced doses, quantitative analysis of ROIs showed that SUVmax and SD in the liver increased gradually (P < 0.05), but SUVmax in the lesions and lesion-to-background ratio (LBR) showed no significant deviation down to 1/30-dose. 100% of the 18F-FDG-avid micro-lesions identified in full-dose images were localised down to 1/15-dose images; while 97% of the lesion were localized in 1/30-dose images.Conclusion: The total-body PET/CT might significantly decrease the administered dose upon maintaining the image quality and diagnostic performance of micro-lesions in paediatric patients. Data suggests that using total-body PET/CT, optimal image quality could be achieved with an administered dose-reduction down to 1/10-dose (0.37 MBq/kg).

Background Lignocellulolytic enzymes are essential for agricultural waste disposal and production of renewable bioenergy. Many commercialized cellulase mixtures have been developed, mostly from saprophytic or endophytic fungal species. The cost of complete cellulose digestion is considerable because a wide range of cellulolytic enzymes is needed. However, most fungi can only produce limited range of highly bioactive cellulolytic enzymes. We aimed to investigate a simple yet specific method for discovering unique enzymes so that fungal species producing a diverse group of cellulolytic enzymes can be identified. Results The culture medium of an endophytic fungus, Daldinia caldariorum D263, contained a complete set of cellulolytic enzymes capable of effectively digesting cellulose residues into glucose. By taking advantage of the unique product inhibition property of β-glucosidases, we have established an improved zymography method that can easily distinguish β-glucosidase and exoglucanase activity. Our zymography method revealed that D263 can secrete a wide range of highly bioactive cellulases. Analyzing the assembled genome of D263, we found over 100 potential genes for cellulolytic enzymes that are distinct from those of the commercially used fungal species Trichoderma reesei and Aspergillus niger. We further identified several of these cellulolytic enzymes by mass spectrometry. Conclusions The genome of Daldinia caldariorum D263 has been sequenced and annotated taking advantage of a simple yet specific zymography method followed by mass spectrometry analysis, and it appears to encode and secrete a wide range of bioactive cellulolytic enzymes. The genome and cellulolytic enzyme secretion of this unique endophytic fungus should be of value for identifying active cellulolytic enzymes that can facilitate conversion of agricultural wastes to fermentable sugars for the industrial production of biofuels.

To evaluate the application value of CT metal artifact correction technology (MACA total of 72 patients who underwent CT re-examination after total hip replacement from December 2018 to March 2020 were enrolled, and the original data were reconstructed by filter backup projection （FBP） and MAC. Select three identical levels in the two sets of reconstructed images and place the same ROI. The selected levels were the initial level, central level, and lower edge of acetabulum. Measure the CT and noise (SD) of metal high and low density artifacts of the three levels area, as well as metal hip joint space, metal para-bone tissue, muscle, bladder and subcutaneous fat, and calculate the average value. Subcutaneous fat value was used as a reference to calculate the SNR and CNR of metal implant para-bone tissue, muscle and bladder. Two radiologists scored the two groups of reconstructed images using blinded method, Kappa's test was used to compare the homogeneity.There were differences between the two groups of reconstructed images in high- and low-density artifact areas, joint gap CT values, and image noise. Compared with the FBP group, the CT value of the high-density area and the joint space of the MAC group decreased, the CT value of the low-density area increased, and the noise value of each area decreased. The SNR and CNR of metal adjacent bone tissue, muscle and bladder were higher in the MAC group than those in the FBP group, and the difference was statistically significant (MAC

In this research, we studied the creep properties of a selective laser melting (SLM)-processed g&cent, strengthened IN939 superalloy along the building direction compared to a conventional cast alloy as a reference specimen. In the as-built condition, high-density dislocations were formed as a result of the SLM process due to the generation of the larger thermal gradient. Post-heat treatment was necessary to obtain specific mechanical properties to match industrial requirements. Two heat treatment conditions were used: the first was lower temperature heat treatment (LTH: solution treatment at 1160 &deg, C/4 h + aging at 850 &deg, C/16 h). The second was higher temperature heat treatment (HTH: solution treatment at 1240 &deg, C/6 h + aging at 850 &deg, C/16 h). Creep tests were conducted at 816 &deg, C/250 MPa. The first and second heat treatment conditions were used for the SLM specimens, but only the first condition was used for the cast alloy (cast-LTH). The SLM specimens in the as-built and LTH conditions showed very poor creep life but good elongation. The poor creep life of the as-built specimen was caused by high dislocation density and the small recrystallized grains formed during testing. In the LTH specimen, poor creep life was due to the formation of the undesirable h phase at the grain boundary, as well as the formation of small recrystallized grains during testing. The creep life of the HTH specimen was 2.7 times longer compared to the LTH specimen. This was because these specimens were covered with recrystallized grains that included low-density dislocations, columnar grain morphology with random orientation, improvement in g&cent, precipitate size, and elimination of undesirable h phase. The cast LTH specimen showed longer creep life than SLM specimens because of coarser grains with low-density dislocations, g&cent, precipitate coarsening during the creep, and the presence of carbides at grain boundaries. In addition, the cast LTH specimen exhibited lower creep strain rate than SLM specimens also helped in creep life improvement.

A hierarchical microstructure strengthened high entropy superalloy (HESA) with superior cost specific yield strength from room temperature up to 1,023 K is presented. By phase transformation pathway through metastability, HESA possesses a hierarchical microstructure containing a dispersion of nano size disordered FCC particles inside ordered L12 precipitates that are within the FCC matrix. The average tensile yield strength of HESA from room temperature to 1,023 K could be 120 MPa higher than that of advanced single crystal superalloy, while HESA could still exhibit an elongation greater than 20%. Furthermore, the cost specific yield strength of HESA can be 8 times that of some superalloys. A template for lighter, stronger, cheaper, and more ductile high temperature alloy is proposed.

This article presents the effect of carbide inoculants additions on microstructure evolution and mechanical properties of Inconel 718 superalloy fabricated by selective laser melting (SLM) process. Flakes of titanium carbide (TiC) and niobium carbide (NbC) were mixed with the Inconel 718 powder and acted as nucleating agents to induce heterogenous nucleation in order to eliminate anisotropic grain structure. By increasing fraction of carbide inoculants, more isotropic grain texture was detected. Furthermore, significant improvements on creep properties have been observed with minor carbide additions. With 0.5 wt% TiC and NbC addition, creep rupture life could be increased from 198.5 h to 449.5 h and 371.8 h, respectively. Moreover, creep strain rate was dramatically decreased from 0.513 × 10−8 to 0.12 × 10−8 s−1 by 0.5 wt% TiC additions. This study has demonstrated that minor carbide addition can have profound impact on the microstructure and property of Inconel718 processed by SLM.

This article presents detailed microstructure characterization of cemented carbide fabricated by selective laser melting process. Nickel-coated tungsten carbide powders were used for this study; the selective laser melting process induced complex microstructure consisting of partially-melted carbide, carbide precipitates and dendritic microstructure. Four phases were identified, i.e. MC, M2C, FCC and η in the as-built specimen. CALPHAD phase diagram was utilized to describe possible phase formation sequence during selective laser melting process, which involved melting, solidification and repeated heating. Although the composition of initial powder was very simple (spherical W2C-WC and Ni-coating), selective laser melting allowed the decomposition of initial carbides, subsequent formation of dendritic structure and precipitation of additional carbides. To the best of authors' knowledge, for the first time, detailed microstructure characterization of cemented carbide fabricated by selective laser melting is presented.

Background Inula helenium L. is an herb whose anti-inflammatory properties are attributed to its active components, the sesquiterpene lactones (SLs). Our previous study demonstrated that the total sesquiterpene lactones isolated from Inula helenium L. (TSL-IHL), consisting mainly of alantolactone (AL) and isoalantolactone (IAL), may have potential in the prevention and treatment of rheumatoid arthritis (RA). However, the effect of TSL-IHL on atopic dermatitis (AD) has not been studied yet. Aim of the study The present study evaluates the potential of TSL-IHL as a treatment for AD. Methods/Study designs The effects of TSL-IHL on the expression of inflammatory genes and the activation of NF-κB signaling pathway in HaCat cells were examined by quantitative real-time PCR and western blotting, respectively, and compared with those of AL and IAL. The protective effect of TSL-IHL against AD was tested in a mouse model induced by 2,4-dinitrochlorobenzene (DNCB), in which AD-like skin lesions were induced in ICR mice by sensitizing once with 100 µl of 7% DNCB painted on their shaved back skin and then challenging with 20 µl of 0.2% DNCB five times on their right ears at 3 day intervals starting on day 5 post-sensitization. Results TSL-IHL, as well as AL and IAL, could all inhibit TNF-α-induced activation of NF-κB and the expression of TNF-α, IL-1, and IL-4 in HaCat cells in a dose-dependent manner in the range of 0.6–2.4 µg/ml. The topical application of TSL-IHL (1% W/W in emollient cream) attenuated DNCB-induced dermatitis severity and right ear swelling. The serum levels of IgE, TNF-α and IFN-γ in TSL-IHL-treated mice were reduced by 81.39%, 89.69%, and 87.85%, respectively, while the mRNA levels of IL-4, IL-5 and IL-13, in the back-skin lesions of TSL-IHL-treated mice were reduced by 39.21%, 40.62% and 48.12%, respectively, compared with the untreated controls. Histopathological examination showed that TSL-IHL treatment reduced epidermis/dermis thickening and dermal inflammatory infiltration in both ear and back skins. Conclusions We suggest that TSL-IHL inhibited the development of AD-like skin symptoms by regulating cytokine expression and may be an effective alternative therapy for AD.