263 research outputs found
Tumor microenvironment in pancreatic ductal adenocarcinoma: Implications in immunotherapy
Pancreatic ductal adenocarcinoma is one of the most aggressive and lethal cancers. Surgical resection is the only curable treatment option, but it is available for only a small fraction of patients at the time of diagnosis. With current therapeutic regimens, the average 5-year survival rate is less than 10% in pancreatic cancer patients. Immunotherapy has emerged as one of the most promising treatment options for multiple solid tumors of advanced stage. However, its clinical efficacy is suboptimal in most clinical trials on pancreatic cancer. Current studies have suggested that the tumor microenvironment is likely the underlying barrier affecting immunotherapy drug efficacy in pancreatic cancer. In this review, we discuss the role of the tumor microenvironment in pancreatic cancer and the latest advances in immunotherapy on pancreatic cancer
Case report: Prenatal diagnosis in the fetus of a couple with both thalassemia and deafness genes
Background: Prenatal diagnosis and genetic counseling play an important role in preventing and controlling birth defects. No reports were found of prenatal diagnosis of couples carrying both the thalassemia and deafness genes. In this study, we presented the prenatal screening and diagnosis of a couple with both thalassemia and deafness genes, contributing to better genetic counseling.Case Report: A couple visited our hospital for a routine prenatal examination. As required by the policy in our region, they underwent screening and genetic diagnosis for thalassemia. Meanwhile, they did not accept the recommendation to test for spinal muscular atrophy and deafness genes. The female was confirmed to be a Hb Quong Sze (Hb QS) carrier (αQSα/αα, βN/βN), and the male had Hb H disease combined with β-thalassemia (--SEA/αCSα, βCDs41-42 (-TTCT)/βN). A prenatal diagnosis of the fetus revealed a Hb CS heterozygote. Subsequent complementary testing showed that the male was a double heterozygote of the GJB2 gene c.299_300delAT combined with c.109G>A, and Sanger sequencing confirmed that the female was a carrier of c.508_511dup in the GJB2. Fortunately, the chorionic villi results indicated that the fetus was only a carrier of deafness.Conclusion: Since both partners carried thalassemia and deafness genes, the couple required prenatal diagnosis for the respective mutations. Expanded carrier screening (ECS) is a more advanced technology that can detect multiple disease genes simultaneously
795-6 Comparison Between Three-Dimensional Reconstruction and Two-Dimensional Imaging for Evaluating Regurgitant Jets: An In Vitro Study
The aim of our study was to investigate the applicability of the 3D reconstruction for evaluating color Doppler regurgitant jet imaging compared to conventional 20 color Doppler flow mapping.MethodsSteady flows (20–80cc/sec) were driven through a rectangular orifice (24mm2, length=8×width) using a steady flow pump. The regurgitant jets were imaged using 3 different Nyquist velocities (35, 52 and 78cm/sec)with an Interspec ultrasound system and analyzed using 3D reconstruction with a Tomtec computer. An oblique “birds eye” view from above the orifice plane gave a side view of the flattened jet. Volumes of 3D regurgitant jets were measured and were compared to the conventional color Doppler 2D maximal jet area.ResultsThe 3D reconstructions showed characteristically elongated and flaring jet propagation for all flow conditions (Figure). Jet areas sliced parallel to the orifice plane provided the most quantifiable jet propagation pattern. A linear relationship between flow rates and 3D jet volumes was obtained (r=0.91, P<0.001) whereas conventional 20 maximal jet areas showed a less well defined relationship with actual flow rates (r=0.87, p<0.01). The consistency of the relationship between flow rates and jet area in 3D volume over the various Nyquist units was also better for 3D volumes.ConclusionOur study suggests that three-dimensional jet volume methods should provide more accurate approaches for quantifying regurgitant jets than the conventional 2D jet area measurement
How do tree species with different successional stages affect soil organic nitrogen transformations?
Organic nitrogen (N) is the most important N component of soil organic matter.However, knowledge on how tree species with different successional stages affect its transformations in soils remains limited. To address this issue, we sampled mineral soils (0−10 cm) in monocultures composed by tree species of different successional stages, including early (black alder and silver birch), early to mid (sycamore and European ash), and late (sweet chestnut, pedunculate oak and European beech), and measured the potential protease activity, the microbial uptake and respiration of 14C-labeled organic N (L-alanine and L-trialanine), and the mineralization of L-alanine N. The activities of alanine aminopeptidase and leucine aminopeptidase (153.8−341.9 and 91.6−147.9 nmol/g/h, respectively), the half-life of the uptake of alanine and trialanine (26.7−39.6 and 60.8−78.6 min, respectively), the half-life of the mineraliztion of alanine and trialanine (1.98−2.45 and 2.98−4.13 h, respectively) by soil microbes were altered by tree species of different successional stages, systematically changing the transformation chain of soil organic N. From trees of early successional stage to that of late, the turnover rates of soil organic N appeared to decrease and the half-life appeared to increase significantly. The (carbon) C:N ratio of soil microbial biomass was positively related to the half-life of 14Clabeled alanine and trialanine mineralization, and was negatively related to the C use efficiency of alanine, suggesting that microbial demand for C could partially drive the assimilation of soil organic N. Our results suggest that the successional stage of tree species play an important role in regulating the soil organic N turnover. An improved understanding of how tree species with different successional stages influence microbial function and soil organic N cycling is beneficial to future afforestation and forest management, alleviating the impacts of global change on the ecosystem
Edge phonon state of mono- and few-layer graphene nanoribbons observed by surface and interference co-enhanced Raman spectroscopy
N configuration control of N-doped carbon for stabilizing Cu nanoparticles: The synergistic effects on oxy-carbonylation of methanol
Abstract(#br)N-doped carbons (NCs) have attracted considerable attention for their outstanding physicochemical properties, including tunable porosity, electronic features and modified surface. Here, we report the preparation of hierarchically porous NCs derived from the direct pyrolysis of ZIFs (ZIF-7 and ZIF-8) and poly– m –phenylenediamine-covered carbon black (P m PDA-C) for the stabilization of Cu nanoparticles (NPs). The configuration of N species can be effectively regulated by changing the ligand of ZIFs and pyrolysis atmosphere. A remarkable N configuration synergistic effect is observed in the oxy-carbonylation of methanol to dimethyl carbonate with molecular oxygen. The results indicate that the Cu NPs on pristine carbon have a turn over frequency (TOF) of 4.4 h −1 for the reaction, while those on NCs from ZIF-8 and ZIF-7 present TOF values as high as 17.9 h −1 and 28.5 h −1 , respectively. The extensive characterizations reveal that NCs with a nitrogen content of 2–5 wt% and a pyrrolic-/pyridinic-N molar ratio of 2–3 are vital for the performance enhancement of Cu NPs. This work shows that the stabilization and enhanced performance of active Cu NPs on NCs are realized by the rational design of precursors to generate the proper N configurations
Satisfaction with care quality and anxiety among family members during nursing home visiting restrictions: The chain mediating effect of emotional regulation and perceived stress
IntroductionThis study aimed to investigate the psychological well-being (perceived stress and anxiety) of Chinese family members during nursing home visiting restrictions and to elucidate the relationships among satisfaction with care quality, emotion regulation, perceived stress, and anxiety.MethodsAn online survey was conducted with a cross-sectional study design. From 18 to 29 January 2022, a total of 571 family members of nursing home residents completed online questionnaires comprising socio-demographic characteristics, satisfaction with care quality, emotion regulation, perceived stress, and anxiety. Mediation analyses were performed to estimate the direct and indirect effects of satisfaction with care quality on anxiety using the PROCESS macro for SPSS.ResultsThe results showed that approximately one-quarter of Chinese family members had anxiety symptoms during nursing home visiting restrictions. Satisfaction with care quality affected anxiety via three mediating paths: (a) through cognitive reappraisal (effect = 0.028); (b) through cognitive reappraisal and perceived stress sequentially (effect = −0.057); and (c) through perceived stress (effect = −0.212). The chain mediating effect (path b) accounted for 23.7% of the total effect.ConclusionsThese findings corroborated our hypothesis that cognitive reappraisal (a kind of emotion regulation strategy) and perceived stress mediated the relationship between satisfaction with care quality and anxiety during nursing home visiting restrictions. Efforts to address family members’ psychological well-being by focusing on cognitive reappraisal should be considered
A facile and general approach for the synthesis of fluorescent silica nanoparticles doped with inert dyes
A general and facile approach was developed for the synthesis of almost monodisperse fluorescent silica nanoparticles (NPs) doped with inert dyes, which are organic fluorophores that are strongly fluorescent but are hydrophobic or lack a covalent binding group. The prepared NPs were mesoporous and the dye molecules were encapsulated in the pores via hydrophobic interaction with the CTAB template. The NPs were stable and highly fluorescent in aqueous solution, and have potential applications in bioanalysis and fluorescence encoding.National Natural Science Foundation of China[20875079, 20835005]; Planned Science and Technology Project of Xiamen, China[3502z20080011]; Specialized Research Fund for the Doctoral Program of Higher Education of China[200803840007
Molecule-scale controlled-release system based on light-responsive silica nanoparticles
We report a molecule-scale controlled-release system based on silica nanoparticles bearing a photoactive o-nitrobenzyl bromide linkage, which allows cage and release of drug or biologically active molecules by light
- …