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To improve the sintering performance of doped barium zirconate, (ZrO2)0.92(Y2O3)0.08 (YSZ) was added and BaZr0.8Y0.2O3-δ (BZY)-x%YSZ (x = 20, 30 and 50% by weight) composite ceramics were prepared by mechanical ball milling combined with high-temperature sintering in air. The crystalline structure, chemical composition, microstructure and electrical properties of the composite electrolytes were characterized by XRD, SEM, TEM, EDS and EIS, respectively. The composite electrolytes only consist of BZY and YSZ phases, and there are no precipitates in BZY/YSZ grain boundaries according to the HR-TEM analysis. YSZ addition can improve the sintering properties of the composite electrolytes. When the composite ceramics with YSZ content of 50 wt% are sintered at 1450 °C for 6 h, the relative density and linear shrinkage are optimal. At 700 °C, the electrical conductivity of BZY-50%YSZ ceramic reaches 1.95 × 10−4 S/cm and 1.67 × 10−4 S/cm in the dry air and moist air, respectively. [ABSTRACT FROM AUTHOR]

Background and Purpose A series of benzothiazole derivatives were screened for immunosuppressive activity; of these compounds BD750 was found to be the most effective immunosuppressant. The purpose of the current study was to determine the immunosuppressive activity of BD750 on T cell proliferation and its potential mode of action. Experimental Approach T cell proliferation, CD25 and CD69 expression and cell cycle distribution were measured in vitro by flow cytometry. Cell viability was determined by CCK-8 assay. Cytokine levels were measured by elisa. The activation of signal-regulated molecules was assessed by Western blot analysis. The effects of BD750 were evaluated in vivo in a mouse model of delayed-type hypersensitivity. Key Results BD750 significantly inhibited mouse and human T cell proliferation, stimulated either by anti- CD3/anti- CD28 monoclonal antibodies or by an alloantigen, in a dose-dependent manner in vitro. No obvious cytotoxic effects of BD750 were observed in our experimental conditions. Furthermore, BD750 did not inhibit CD25 and CD69 expression or IL-2 and IL-4 secretion, but induced cell cycle arrest at the G0/ G1 phase in activated T cells. In IL-2-stimulated CTLL-2 cells and primary activated T cells, BD750 inhibited cell proliferation and STAT5 phosphorylation, but not Akt or p70S6 K phosphorylation. BD750 also reduced the T cell-mediated delayed-type hypersensitivity response in mice in a dose-dependent manner. Conclusion and Implications These data indicate that BD750 inhibits IL-2-induced JAK3/ STAT5-dependent T cell proliferation. BD750 has the potential to be used as a lead compound for the design and development of new immunosuppressants for preventing graft rejection and treating autoimmune diseases. [ABSTRACT FROM AUTHOR]

Atmospheric conditions are often connected with the occurrence of high pollution episodes especially in urban areas. As part of the PRIDE-PRD2006 intensive campaign, atmospheric boundary layer (ABL) measurements were carried out at Qingyuan, Panyu and Xinken in the Pearl River Delta (PRD) from 1 July to 30 July of 2006. It was found that in summer, the surface winds in PRD are more controlled by the south, and there usually is vertical wind shear at the height of 800m or so, therefore, PRD is often influenced by the tropical cyclone/typhoon. The subsidence and precipitation from a tropical cyclone will affect the air quality of PRD. Under the subsidence, the wind speed in ABL and the height of ABL will decrease and result in high level concentrations. When the background wind speed is small or calm, the wind profile at Panyu and Xinken change dramatically with height, which is perhaps caused by the local circulations, such as the sea land breeze. For more understanding about the ABL of PRD, the simulations by the WRF mesoscale model were used to analyse the ABL characteristics in PRD. From three kinds of weather condition simulations (subsidence days, rainy days and sunny days) by WRF model, it was found that the simulated temperature, wind fields in these three cases were moderately consistent with the measurements. The results show that the diurnal variation of ABL in subsidence days and sunny days are obvious, but the diurnal variation of ABL on rainy days is not obvious. The ABL is obviously affected by the local circulation and the features of ABL are different in various stations. A simulation focus on high pollution episode during the subsidence days from 12-15 July 2006, occurred under high pressure conditions, accompanied by a tropical cyclone "Bilis". Comparing the simulated vertical wind fields and temperature structure with the ABL measurements at Xinken, Panyu and Qingyuan station, it was found that, the modelled and measured atmospheric fields reveal that there are two different kinds of ABL characteristics in PRD: when the surface winds in PRD were light or almost calm, the local circulation was dominated, such as the sea-land breeze at Xinken station and the mountain-valley circulation at Qingyuan station. When the surface winds were strong, the stations were under the same background weather system and the wind directions were almost the same. Furthermore, the modelled results also suggest that the high Air Pollutant index (API) episode was caused predominately by subsidence. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulation of multi-phase flow is essential to evaluate the feasibility of a liquid protection scheme for the power plant chamber. The level set method is one of the best methods for computing and analyzing the motion of interface among the multi-phase flow. This paper presents a general formula for the second-order projection method combined with the level set method to simulate unsteady incompressible multi-phase flow with/out phase change flow encountered in fusion science and engineering. The third-order ENO scheme and second-order semi-implicit Crank–Nicholson scheme is used to update the convective and diffusion term. The numerical results show this method can handle the complex deformation of the interface and the effect of liquid–vapor phase change will be included in the future work. [Copyright &y& Elsevier]

We introduce a discrete mathematical model for the mechanical behaviour of a planar slice of human corneal tissue, in equilibrium under the action of physiological intraocular pressure (IOP). The model considers a regular (two-dimensional) network of structural elements mimicking a discrete number of parallel collagen lamellae connected by proteoglycan-based chemical bonds (crosslinks). Since the thickness of each collagen lamella is small compared to the overall corneal thickness, we upscale the discrete force balance into a continuum system of partial differential equations and deduce the corresponding macroscopic stress tensor and strain energy function for the micro-structured corneal tissue. We demonstrate that, for physiological values of the IOP, the predictions of the discrete model converge to those of the continuum model. We use the continuum model to simulate the progression of the degenerative disease known as keratoconus, characterized by a localized bulging of the corneal shell. We assign a spatial distribution of damage (i.e. reduction of the stiffness) to the mechanical properties of the structural elements and predict the resulting macroscopic shape of the cornea, showing that a large reduction in the element stiffness results in substantial corneal thinning and a significant increase in the curvature of both the anterior and posterior surfaces., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)

Hepatosplenic candidiasis (HSC) is a rare type of candidiasis that can occur in patients with hematologic malignancies, hematopoietic stem cell transplantation. At present, there is still a lack of studies on HSC in patients with hematologic disorders. Based on The Chinese Guidelines for the Diagnosis and Treatment of Invasive Fungal Disease in Patients with Hematological Disorders and Cancers (the 6th revision), We retrospectively analyzed the clinical characteristics and prognosis of patients with HSC treated in Peking University Institute of Hematology from 2008 to 2022. Finally, eighteen patients were included, with 1 (5.6%) proven, 2 (11.1%) probable, and 15 (83.3%) possible HSC. Among them, 3 (16.7%) patients occurred after haploid hematopoietic stem cell transplantation and 15 (83.3%) patients occurred after chemotherapy. 6 (33.3%) patients had positive blood cultures, including 4 cases of Candida tropicalis and 2 cases of Candida albicans. At 4 weeks of antifungal therapy, 10 (58.8%) patients achieved partial response (PR), At 8 weeks, 1 (6.3%) patients achieved complete response and 10 (62.5%) patients achieved PR. At 6 months after diagnosis, 3 (16.7%) patients died of hematopoietic recurrence, and none of them died of HSC. As a rare fungal infection disease, HSC has a low positive rate of microbiological and histological examinations, a persistent treat cycle, and has difficulty in remission, reminding us of the need for vigilance in patients with hematopoietic disorders and persistent fever.

Human parvovirus B19 (HPVB19) belongs to Parvoviridae, a genus of erythrovirus, and has been associated with various human diseases, and HPVB19 infection is one of the most important causes of refractory anemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study retrospectively analyzed 24 patients with HSCT combined with HPVB19 infection to collate and summarize the clinical presentation, treatment, and regression of patients with combined HPVB19 infection after allo-HSCT and provide experience in the management of HPVB19 infection after allo-HSCT. The median age of the patients with HPVB19 infection was 25 years, and the median time of infection occurrence was +107 days after transplantation, and 22 (91.7% ) had anemia with a median hemoglobin (HGB) level of 77.5 (46-149) g/L, and 13 (54.2% ) had new-onset anemia or persistent decline in HGB. The median length of hospital stay was 19 days. Among patients with new-onset anemia or persistent decline in HGB, the mean increase in HGB after treatment with intravenous immunoglobulin and/or antiviral therapy was 15.69 g/L, and treatment was effective in 10 (76.92% ) patients. HPVB19 infection should be alerted to the development of refractory anemia after HSCT; despite the lack of specific treatment, the overall prognosis of HPVB19-infected patients is good.

Objective: To analyze the clinical value of real-time PCR for virus detection in the diagnosis and treatment of patients after allo-HSCT who had no infection evidence of pneumonia using routine pathogen detection panel. Methods: The clinical data of 71 episodes with acute lung injury from May 2015 to March 2017 after allo-HSCT in hematology department of Peking University People's Hospital (PKUPH) were retrospectively analyzed. PCR for virus detection and other routine pathogen detection tests were performed on bronchoalveolar lavage fluid (BALF) samples. Results: Among 71 episodes with acute lung injury, a total of 15 patients were diagnosed as lower respiratory tract disease merely associated with virus (detection rate of 21.13%) , 19 episodes were absent of lower respiratory tract infection. The median time from allo-HSCT to the occurrence of lung injury were 176 (49-1 376) d and 196 (57-457) d respectively ( z =-0.191, P =0.864) . There were no statistical differences for baseline characteristics and clinical features between two groups. The 100-day attributable mortalities were 13.3% (2/15) and 26.3% (5/19) ( χ (2)=0.864, P =0.426) . Patients with low-dose steroids treatment had favorable outcome than those with high-dose steroids treatment (the dose of methylprednisolone ≥250 mg/d as standard) [4.2% (1/24) vs 60.0% (6/10) ]. In patients with detectable virus in BALF, 2 patients died with early high-dose steroids treatment, while 11 patients survived with no steroids treatment or late application. Conclusions: Virus infection should be considered in post-HSCT pneumonia patient with negative result using routine pathogen detection panel. Expanding virus detection panel by PCR in BALF could increase diagnostic precision and might be instructive to treatment.

Objective: To assess the validity of Caprini risk assessment model in prediction of venous thromboembolism in Chinese hospitalized patients in a general hospital. Methods: Medical record review was performed in Beijing Shijitan Hosital for all eligible hospitalized patients who underwent screening for venous thromboembolism between January and December 2015. The Caprini score of patients with or without venous thromboemboilism and incidence of venous thromboembolism in patients with various Caprini risk levels, surgery and medical patients was compared. Results: A total of 6 966 inpatients were enrolled. Three hundred and ninety-six patients developed venous thromboembolism. The Caprini median score of patients with venous thromboemboilism was 5 (3-7), which higher than 3(2-5) of patients without venous thromboembolism( Z =-13.68, P <0.01). Incidence of venous thromboembolism of patients in low, moderate, high, highest risk level was 1.0%, 1.8%, 5.7%, 10.6%, respectively. There was no statistically significant difference of incidence between low and moderate risk patients ( OR =1.88, 95% CI : 0.89-3.99, P >0.05), but significant difference between moderate and high risk ( OR =3.23, 95% CI : 2.06-5.06, P <0.01), high and highest risk patients ( OR =1.97, 95% CI : 1.59-2.45, P <0.01). There was no incidence difference of venous thromboembolism between surgery and medical patients in the same Caprini level of low (χ(2)=3.58 , P >0.05), moderate(χ(2)=2.89, P >0.05), high(χ(2)=0.46, P >0.05), highest risk(χ(2)=1.61, P >0.05). Conclusion: Caprini risk assessment model can effectively predict the occurence of venous thromboembolism in Chinese hospitalized patients with high risk of VTE(Caprini score >2)in a general hospital.

The purpose of this study was to investigate the expression of interleukin (IL)-21 in rats with inflammatory bowel disease (IBD). Fifty adult Wistar rats were randomly divided into two groups: DSS, in which IBD was induced by giving the rats 7% DSS for seven days in their water, and a water control. Blood samples were collected and the concentration of IL-21 in serum was detected by enzyme-linked immunosorbent assay. Colon tissue of rats was examined by immunohistochemical staining. Rats in the DSS group were lethargic, with matte coat color and decreasing body weight. In the DSS group, brown loss stool appeared after four days, and blood appeared in the stool along with dark red hematocele in the intestinal cavity after ten days. Rats in the control group were active and body weight increased regularly. Their stool was black and granular and the color of the intestinal canal was pink. The original body weight of all rats in both groups was similar but seven days after induction of IBD, the weight of the DSS rats dropped significantly compared to the control group (P < 0.05). Serum IL-21 levels were 1.37 ± 0.43 pg/mL in the control group and 3.86 ± 1.27 pg/mL in the DSS group (P < 0.05). More IL-21 positive cells were detected in the intestinal mucosal epithelial cell layer and the lamina propria of the submucosa in the DSS group than in the control group. In conclusion, IL-21 is involved in the pathological process of IBD.

Polymorphisms in the vitamin D receptor (VDR) gene are associated with idiopathic short stature (ISS) in several countries. This study aimed to identify a possible correlation between polymorphisms in the VDR promoter in Chinese children with ISS and the efficacy of the recombinant human growth hormone (rhGH) treatment. Pre-pubertal children with ISS and healthy age- and gender-matched children (N = 95 each) were enrolled in this study. Two single nucleotide polymorphisms (SNPs) in the VDR promoter (rs11568820 at the Cdx-2-binding site upstream of exon 1e and rs4516035 at -1012 upstream of exon 1a) were typed. The growth velocity, standard deviation score (SDS) of height for chronological age, height SDS for bone age, predicted adult height, and serum insulin-like growth factor 1 (IGF-1) and IGF-binding protein 3 (IGFBP-3) levels of the ISS patients were determined before and 6 months after rhGH treatment. No significant differences were observed in the genotype frequencies between the ISS cases and controls. After rhGH treatment, the growth velocity of the A/G genotype at the Cdx-2-binding site SNP locus was significantly higher than that of the G/G genotype; the IGF-1 and IGFBP-3 levels were also higher in the treated group than the untreated group. However, these changes were independent of the VDR-promoter genotype. Polymorphisms in the VDR promoter may not result in the pathogenesis of ISS in Chinese children. The A/G genotype showed a significantly higher growth velocity than the G/G genotype, and may represent a short-term marker of growth potential.

The recent development of gene transfer approaches in plants and animals has revealed that transgene can undergo silencing after integration in the genome. Host genes can also be silenced as a consequence of the presence of a homologous transgene. More and more investigations have demonstrated that double-stranded RNA can silence genes by triggering degradation of homologous RNA in the cytoplasm and by directing methylation of homologous nuclear DNA sequences. Analyses of Arabidopsis mutants and plant viral suppressors of silencing are unraveling RNA-silencing mechanisms and are assessing the role of methylation in transcriptional and posttranscriptional gene silencing. This review will focus on double-stranded RNA mediated mRNA degradation and gene inactivation in plants.