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Background: Breast cancer is one of the most common malignant tumors in women. A noninvasive ultrasound examination can identify mammary-gland-related diseases and is well tolerated by dense breast, making it a preferred method for breast cancer screening and of significant clinical value. However, the diagnosis of breast nodules or masses via ultrasound is performed by a doctor in real time, which is time-consuming and subjective. Junior doctors are prone to missed diagnoses, especially in remote areas or grass-roots hospitals, due to limited medical resources and other factors, which bring great risks to a patient’s health. Therefore, there is an urgent need to develop fast and accurate ultrasound image analysis algorithms to assist diagnoses. Methods: We propose a breast ultrasound image-based assisted-diagnosis method based on convolutional neural networks, which can effectively improve the diagnostic speed and the early screening rate of breast cancer. Our method consists of two stages: tumor recognition and tumor classification. (1) Attention-based semantic segmentation is used to identify the location and size of the tumor; (2) the identified nodules are cropped to construct a training dataset. Then, a convolutional neural network for the diagnosis of benign and malignant breast nodules is trained on this dataset. We collected 2057 images from 1131 patients as the training and validation dataset, and 100 images of the patients with accurate pathological criteria were used as the test dataset. Results: The experimental results based on this dataset show that the MIoU of tumor location recognition is 0.89 and the average accuracy of benign and malignant diagnoses is 97%. The diagnosis performance of the developed diagnostic system is basically consistent with that of senior doctors and is superior to that of junior doctors. In addition, we can provide the doctor with a preliminary diagnosis so that it can be diagnosed quickly. Conclusion: Our proposed method can effectively improve diagnostic speed and the early screening rate of breast cancer. The system provides a valuable aid for the ultrasonic diagnosis of breast cancer.

Abstract Background The homeostasis of mesenchymal stem cells (MSCs) is modulated by both their own intracellular molecules and extracellular milieu signals. Hematopoiesis in the bone marrow is maintained by niche cells, including MSCs, and it is indispensable for life. The role of MSCs in maintaining hematopoietic homeostasis has been fully elucidated. However, little is known about the mechanism by which hematopoietic cells reciprocally regulate niche cells. The present study aimed to explore the close relationship between MSCs and hematopoietic cells, which may be exploited for the development of new therapeutic strategies for related diseases. Methods In this study, we isolated cells from the offspring of Tie2Cre + and Ptenflox/flox mice. After cell isolation and culture, we investigated the effect of hematopoietic cells on MSCs using various methods, including flow cytometry, adipogenic and osteogenic differentiation analyses, quantitative PCR, western bloting, and microCT analysis. Results Our results showed that when the phosphatase and tensin homolog deleted on chromosome 10 (Pten) gene was half-deleted in hematopoietic cells, hematopoiesis and osteogenesis were normal in young mice; the frequency of erythroid progenitor cells in the bone marrow gradually decreased and osteogenesis in the femoral epiphysis weakened as the mice grew. The heterozygous loss of Pten in hematopoietic cells leads to the attenuation of osteogenic differentiation and enhanced adipogenic differentiation of MSCs in vitro. Co-culture with normal hematopoietic cells rescued the abnormal differentiation of MSCs, and in contrast, MSCs co-cultured with heterozygous null Pten hematopoietic cells showed abnormal differentiation activity. Co-culture with erythroid progenitor cells also revealed them to play an important role in MSC differentiation. Conclusion Our data suggest that hematopoietic cells function as niche cells of MSCs to balance the differentiation activity of MSCs and may ultimately affect bone development.

Clinker bricks were popular as a facade material in the United States between the 1890s and the 1930s. However, this material was unknown to Chinese builders and was seldom found in Chinese modern architecture from 1840 to 1949. The Smart Memorial Gymnasium built in the years 1934–1937 in the Tiancizhuang Campus of Soochow University (Suzhou, China) is one of the rare examples of a building featuring clinker bricks in modern China. Notably, those clinker bricks were not imported but locally manufactured. Despite the heritage significance of the Smart Memorial Gymnasium as part of a major historical and cultural site protected at the national level in China, the history and characteristics of those historical bricks have remained virtually unexplored. This study first provides a historical analysis of those bricks, giving insights into the general knowledge of this construction material around that time based on British and American historical sources from the 19th and 20th centuries, with a focus on historical treaties and documents. This analysis sheds light on the raw materials mixtures of clinker bricks, their manufacturing processes, and their architectural applications at the time. Moreover, this study presents a physicochemical analysis of the clinker bricks employed at Soochow University, focusing on the correlation between historical studies and physicochemical characteristics, as well as the materials’ characteristics that respond to the natural environment. X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), and total immersion tests were employed to investigate the physicochemical properties of the bricks at various locations of the Smart Memorial Gymnasium facades. Our findings deepen the knowledge and understanding of clinker bricks transferred from the West to China in the early 20th century. Additionally, our results reveal the chemical composition and physical characteristics of different types of clinker bricks used in the Smart Memorial Gymnasium, outlining practical implications and future research directions. Overall, this study lays a foundation for the heritage recognition and conservation of Chinese clinker bricks.

In this work, a novel integrable evolution system in the sense of Lax’s scheme associated with a mixed spectral Ablowitz-Kaup-Newell-Segur (AKNS) matrix problem is first derived. Then, the time dependences of scattering data corresponding to the mixed spectral AKNS matrix problem are given in the inverse scattering analysis. Based on the given time dependences of scattering data, the reconstruction of potentials is carried out, and finally analytical solutions with four arbitrary functions of the derived integrable evolution system are formulated. This study shows that some other systems of integrable evolution equations under the resolvable framework of the inverse scattering method with mixed spectral parameters can be constructed by embedding different spectral parameters and time-varying coefficient functions to the known AKNS matrix spectral problem.

The transition from hemogenic endothelial cells (HECs) to hematopoietic stem/progenitor cells (HS/PCs), or endothelial to hematopoietic transition (EHT), is a critical step during hematopoiesis. However, little is known about the molecular determinants of HECs due to the challenge in defining HECs. We report here the generation of GATA2w/eGFP reporter in human embryonic stem cells (hESCs) to mark cells expressing GATA2, a critical gene for EHT. We show that during differentiation, functional HECs are almost exclusively GATA2/eGFP+. We then constructed a regulatory network for HEC determination and also identified a panel of positive or negative surface markers for discriminating HECs from non-hemogenic ECs. Among them, ITGB3 (CD61) precisely labeled HECs both in hESC differentiation and embryonic day 10 mouse embryos. These results not only identify a reliable marker for defining HECs, but also establish a robust platform for dissecting hematopoiesis in vitro, which might lead to the generation of HSCs in vitro.

Siberian apricot (Prunus sibirica L.), an ecologically and economically important tree species with a high degree of tolerance to a variety of extreme environmental conditions, is widely distributed across the mountains of northeastern and northern China, eastern and southeastern regions of Mongolia, Eastern Siberia, and the Maritime Territory of Russia. However, few studies have examined the genetic diversity and population structure of this species. Using 31 nuclear microsatellites, we investigated the level of genetic diversity and population structure of Siberian apricot sampled from 22 populations across China. The number of alleles per locus ranged from 5 to 33, with an average of 19.323 alleles. The observed heterozygosity and expected heterozygosity ranged from 0.037 to 0.874 and 0.040 to 0.924 with average values of 0.639 and 0.774, respectively. A STRUCTURE-based analysis clustered all of the populations into four genetic clusters. Significant genetic differentiation was observed between all population pairs. A hierarchical analysis of molecular variance attributed about 94% of the variation to within populations. No significant difference was detected between the wild and semi-wild groups, indicating that recent cultivation practices have had little impact on the genetic diversity of Siberian apricot. The Mantel test showed that the genetic distance among the populations was not significantly correlated with geographic distance (r = 0.4651, p = 0.9940). Our study represents the most comprehensive investigation of the genetic diversity and population structure of Siberian apricot in China to date, and it provides valuable information for the collection of genetic resources for the breeding of Siberian apricot and related species.

Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation. The outstanding electronic structure and physicochemical properties of graphitic carbon nitride (g-C3N4), together with unique metal-free characteristic, make them ideal candidates for advanced photocatalysts construction. This review summarizes the up-to-date advances on g-C3N4 based photocatalysts from ingenious-design strategies and diversified photocatalytic applications. Notably, the advantages, fabrication methods and limitations of each design strategy are systemically analyzed. In order to deeply comprehend the inner connection of theory–structure–performance upon g-C3N4 based photocatalysts, structure/composition designs, corresponding photocatalytic activities and reaction mechanisms are jointly discussed, associated with introducing their photocatalytic applications toward water splitting, carbon dioxide/nitrogen reduction and pollutants degradation, etc. Finally, the current challenges and future perspectives for g-C3N4 based materials for photocatalysis are briefly proposed. These design strategies and limitations are also instructive for constructing g-C3N4 based materials in other energy and environment-related applications.

Vascular diseases, a leading cause of death in human, are strongly associated with pathological damage to blood vessels. The selenoprotein (Sel) have been reported to play important roles in vascular disease. However, the role of SelO in vascular disease has not been conclusively investigated. The present experiment was to investigate the regulatory mechanism of the effect of SelO on the permeability of vascular endothelial. The H.E staining, FITC-Dextran staining, Dil-AC-LDL staining and FITC-WGA staining showed that vascular structure was damaged, and intercellular junctions were disrupted with selenium (Se)-deficient. Immunohistochemistry, qPCR and Western blot revealed decreased expression of the adhesion plaque proteins vinculin, talin and paxillin, decreased expression of the vascular connectivity effector molecules connexin, claudin-1 and E-cadherin and increased expression of JAM-A and N-cadherin, as well as decreased expression of the ZO-1 signaling pathways ZO-1, Rock, rhoGEF, cingulin and MLC-2. In a screening of 24 Sel present in mice, SelO showed the most pronounced changes in vascular tissues, and a possible association between SelO and vascular intercellular junction effectors was determined using IBM SPSS Statistics 25. Silencing of SelO, vascular endothelial intercellular junction adverse effects present. The regulatory relationship between SelO and vascular endothelial intercellular junctions was determined. The results showed that Se deficiency lead to increased vascular endothelial permeability and vascular tissue damage by decreasing SelO expression, suggesting a possible role for SelO in regulating vascular endothelial permeability.

BackgroundBurnout has become a prominent issue as the increase of workload in family doctor team members in primary healthcare institutions during the promotion of contracted family doctor services. There is still a lack of research comparing the differences in burnout among family doctor team members in different types of primary healthcare institutions.ObjectiveTo compare burnout prevalence and associated factors between family doctors in community/township health centers, and those in community health stations/village clinics, providing a basis for improving the mental health status and team stability of family doctors, as well as the quality of services provided by them.MethodsFrom August 1 to 21, 2020, a multistage cluster random sampling method was used to select 760 family doctor team members〔201 (26.4%) working at community/township health centers, and 559 (73.6%) working at community health stations/village clinics〕 as the participants from primary healthcare institutions in 6 counties/county-level cities /districts of Taian City, Shandong Province. They were invited to attend a survey to complete Demographic Questionnaire and the Chinese version of Maslach Burnout Inventory-General Survey (MBI-GS) .ResultsOverall, the prevalence of burnout among the participants was 68.9% (524/760) . Overall, the prevalence of burnout among the participants was 68.9% (524/760) , and the prevalence of burnoutof family doctor team members in community/township health centers and community health stations/village clinics was 63.7% (128/201) and 70.8% (396/559) , respectively. The levels of burnout of family doctor team members in community health stations/village clinics was higher than that of those in community/township health centers, with a statistically significant difference (P4 000 yuan is lower than that with monthly income

Objective To study the effect of carboxyamidotriazole (CAI) on CD8+T cells, and to explore the critical mechanism of CAI in reinforcing cytotoxicity of activated T cells. Methods CD8+T cells of mouse were isolated by immunomagnetic beads and divided into control group, CAI group, ZK756326 (Ca2+ activator) group and CAI+ZK756326 group. Flow cytometry was used to detect the level of intracellular free calcium ions in CD8+T cells; Enzyme-linked immunosorbent assay was used to detect the expression of intracellular calcineurin (CaN); Immunoflu- orescence staining was used to detect NFAT2 nuclear transportation; Chromatin immunoprecipitation-qPCR was used to detect the expression of PD-1 regulated by NFAT2. Mice spleen cytotoxic T lymphocytes (CTLs) were isolated and examined for the expression of PD-1 in CD8+T cells by flow cytometry. Results Intracellular Ca2+ concentration in CD8+T cells significantly decreased in the CAI group (P＜0.001), while intracellular Ca2+ concentration increased in the CAI+ZK756326 group(P＜0.01); CAI significantly decreased the content of calcineurin phosphatase in CD8+T cells (P＜0.001);CAI significantly inhibited NFAT2 nuclear transportation (P＜0.001) and significantly inhibited PD-1 transcription process depend on NFAT2 (P＜0.001); CAI significantly reduced the proportion of PD-1+CD8+T cells in mice spleen CTLs cells (P＜0.001). Conclusions CAI inhibits NFAT2 nuclear translocation by decreasing the level of calcium ions in the CD8+ T cells and inhibiting the expression of calcineurin, thereby reducing the expression of PD-1 in CD8+ T cells, which facilitated immunotherapy intervention.

Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation. The outstanding electronic structure and physicochemical properties of graphitic carbon nitride (g-C3N4), together with unique metal-free characteristic, make them ideal candidates for advanced photocatalysts construction. This review summarizes the up-to-date advances on g-C3N4 based photocatalysts from ingenious-design strategies and diversified photocatalytic applications. Notably, the advantages, fabrication methods and limitations of each design strategy are systemically analyzed. In order to deeply comprehend the inner connection of theory--structure--performance upon g-C3N4 based photocatalysts, structure/composition designs, corresponding photocatalytic activities and reaction mechanisms are jointly discussed, associated with introducing their photocatalytic applications toward water splitting, carbon dioxide/nitrogen reduction and pollutants degradation, etc. Finally, the current challenges and future perspectives for g-C3N4 based materials for photocatalysis are briefly proposed. These design strategies and limitations are also instructive for constructing g-C3N4 based materials in other energy and environment-related applications. [ABSTRACT FROM AUTHOR]