Syndecan-2 selectively regulates VEGF-induced vascular permeability.

Vascular endothelial growth factor (VEGF)- driven increase in vascular permeability is a key feature of many disease states associated with inflammation and ischemic injury, contributing significantly to morbidity and mortality in these settings. Despite its importance, no specific regulators that preferentially control VEGF-dependent increase in permeability versus its other biological activities, have been identified. Here we report that a proteoglycan Syndecan-2 (Sdc2) regulates the interaction between a transmembrane phosphatase DEP1 and VEGFR2 by controlling cell surface levels of DEP1. In the absence of Sdc2 or the presence of an antibody that blocks Sdc2-DEP1 interaction, increased plasma membrane DEP1 levels promote selective dephosphorylation of the VEGFR2 Y951 site that is involved in permeability control. Either an endothelial-specific Sdc2 deletion or a treatment with an anti-Sdc2 antibody result in a highly significant reduction in stroke size due to a decrease in intracerebral edema.

Atomically dispersed Ni in cadmium-zinc sulfide quantum dots for high-performance visible-light photocatalytic hydrogen production.

Catalysts with a single atom site allow highly tuning of the activity, stability, and reactivity of heterogeneous catalysts. Therefore, atomistic understanding of the pertinent mechanism is essential to simultaneously boost the intrinsic activity, site density, electron transport, and stability. Here, we report that atomically dispersed nickel (Ni) in zincblende cadmium-zinc sulfide quantum dots (ZCS QDs) delivers an efficient and durable photocatalytic performance for water splitting under sunlight. The finely tuned Ni atoms dispersed in ZCS QDs exhibit an ultrahigh photocatalytic H2 production activity of 18.87 mmol hour-1 g-1. It could be ascribed to the favorable surface engineering to achieve highly active sites of monovalent Ni(I) and the surface heterojunctions to reinforce the carrier separation owing to the suitable energy band structures, built-in electric field, and optimized surface H2 adsorption thermodynamics. This work demonstrates a synergistic regulation of the physicochemical properties of QDs for high-efficiency photocatalytic H2 production.

Paradoxical aortic stiffening and subsequent cardiac dysfunction in Hutchinson-Gilford progeria syndrome.

Hutchinson-Gilford progeria syndrome (HGPS) is an ultra-rare disorder with devastating sequelae resulting in early death, presently thought to stem primarily from cardiovascular events. We analyse novel longitudinal cardiovascular data from a mouse model of HGPS (LmnaG609G/G609G) using allometric scaling, biomechanical phenotyping, and advanced computational modelling and show that late-stage diastolic dysfunction, with preserved systolic function, emerges with an increase in the pulse wave velocity and an associated loss of aortic function, independent of sex. Specifically, there is a dramatic late-stage loss of smooth muscle function and cells and an excessive accumulation of proteoglycans along the aorta, which result in a loss of biomechanical function (contractility and elastic energy storage) and a marked structural stiffening despite a distinctly low intrinsic material stiffness that is consistent with the lack of functional lamin A. Importantly, the vascular function appears to arise normally from the low-stress environment of development, only to succumb progressively to pressure-related effects of the lamin A mutation and become extreme in the peri-morbid period. Because the dramatic life-threatening aortic phenotype manifests during the last third of life there may be a therapeutic window in maturity that could alleviate concerns with therapies administered during early periods of arterial development.

[Clinicopathologic features and prognostic analysis of 240 patients with gastric neuroendocrine neoplasms].

Objective: To investigate clinicopathological features and prognostic factors of gastric neuroendocrine tumors (G-NEN). Methods: Clinical and pathological data of patients with G-NEN diagnosed by pathological examination in Chinese PLA General Hospital from January 2000 to June 2018 were retrospectively analyzed in this case-control study. Patients with complicated visceral lesions, other visceral primary tumors, mental disorders and incomplete clinicopathological data were excluded. Finally, 240 hospitalized patients who met the inclusion criteria were enrolled. Physical examination information, tumor characteristics and pathological characteristics of patients were summarized. The Cox regression models were used to analyze the risk factors affecting G-NEN and the survival conditions were described by Kaplan-Meier survival curves and log-rank test. Results: In 240 patients with G-NEN, the mean age was (60.3±10.1) years; 181 were male (75.4%) and 59 females (24.6%); mean tumor diameter was (4.2±2.8) cm; 51 cases (21.2%) were neuroendocrine tumor (NET), 139 cases (57.9%) neuroendocrine carcinoma (NEC), 50 cases (20.8%) mixed neuroendocrine carcinoma (MANEC); 28 cases (11.7%) were G1 low grades, 34 cases (14.2%) G2 medium grades, and 178 cases (74.2%) G3 high grades; tumor infiltration depth T1 to T4 were 44 cases (18.3%), 27 cases (11.2%), 60 cases (25.0%) and 109 cases (45.4%) respectively; 163 cases (67.9%) developed lymphatic metastasis and 46 patients (19.2%) distant metastasis; tumor stage from stage I to stage IV were 55 cases (22.9%), 42 cases (17.5%), 94 cases (39.2%) and 53 cases (22.1%) respectively. Of the 240 G-NEN patients, 223 cases (92.9%) were followed up. The median survival time of the patients was 39.2 (95% CI: 29.1 to 47.5) months. Univariate survival analysis showed that age ≥ 60 years, tumor diameter ≥ 4.2 cm, tumor grade G3, lymphatic metastasis, distant metastasis, and tumor stage III-IV were risk factors for G-NEN patients. Multivariate survival analysis revealed that lymphatic metastasis (HR=1.783, 95%CI: 1.007-3.155, P=0.047) and distant metastasis (HR=2.288, 95% CI: 1.307-4.008, P=0.004) were independent risk factors of the prognosis. Further analysis of the G3 subgroup of G-NEN showed that the 5-year survival rate of NET-G3 was 76.19%, which was significantly higher than that of NEC-G3 and MANEC-G3 (15.60% and 24.73%, P=0.012). Conclusions: Most G-NEN patients are in advanced stage at diagnosis. Lymphatic metastasis and distant metastasis indicate poor prognosis. The prognosis of high proliferation NET-G3 patients is better as compared to those of NEC-G3 and MANEC-G3. This classification is worth further attention.

Relationship between medial plica and medial femoral condyle--a three-dimensional dynamic finite element model.

BACKGROUND: Many researches reported that the pathologic medial plica impinges on the facing medial femoral condyle during knee motion and leads to erosive changes of the articular cartilage. The purpose of this study was to construct a simplified three-dimensional dynamic finite element human knee model to evaluate the dynamics behaviour between different types of medial plicae with the facing medial femoral condyles during knee motion. METHODS: A three-dimensional dynamic finite element model composed of femur, tibia, covering cartilage and medial plica was developed. The kinematics of this simulation model was verified by previous findings during arthroscopic examination. The validated model was used to investigate and compare the magnitudes of the cyclic pressures acting on the cartilage of the medial femoral condyles by three different types of medial plicae with various Young's moduli. FINDINGS: All types of plicae remained in contact with the medial femoral condyles and shifted medially when the knees moved from extension to flexion. The contact pressures were positively correlated with the Young's moduli of the medial plicae. During the whole range of motion, the maximum contact pressures of all simulation scenarios occurred when the knees moved beyond 50° of flexion. When the Young's moduli of medial plicae were set greater than 60 MPa, all types of medial plicae would elicit contact pressures greater than 10 MPa on the medial femoral condyles. INTERPRETATION: The close relationship and possible high contact pressure between fibrotic medial plica and medial femoral condyle during knee motion might be a cause of cartilage damage on the medial femoral condyle and warrants further investigation.

Transjugular intrahepatic portosystemic shunt with an autologous vein-covered stent: results in a swine model.

PURPOSE: To investigate the feasibility, safety, and efficacy of an autologous vein-covered stent (AVCS) to prevent shunt stenosis in a porcine transjugular intrahepatic portosystemic shunt (TIPS) model. MATERIALS AND METHODS: TIPS were created with an AVCS in 12 healthy domestic swine and with a bare stent in 10 additional swine. Tissue response was compared with use of venography, histology, and computerized morphometry analysis 2 weeks after implantation. Differences between AVCS and noncovered stents (established by a t-test), as well as regional differences within a single stent (established by an f test), were considered significant at P <.05. RESULTS: Twenty of 22 TIPS procedures were technically successful. Ten of 12 shunts with an AVCS (83%) and two of 10 with bare stents (20%) remained patent (<50% diameter narrowing) at euthanasia 2 weeks later (P <.01). Histologic evaluation of harvested bare stents showed marked intimal hyperplasia (IH), composed of smooth muscle cells, myofibroblasts, and fibroblasts. In contrast, the AVCS were remarkably free of IH and thromboses. In patent TIPS in both groups, endothelial coverage of the luminal surface was present histologically. IH accounted for 57% (26.27/45.79) of total stent cross-sectional lumen area in the control group and 21% (8.34/39.54) in the AVCS group (P <.01), with no intrashunt differences (P >.05). CONCLUSION: Based on short-term follow-up, AVCS significantly improved TIPS patency by prevention of both IH and in-stent thrombosis. TIPS created with an AVCS was feasible and safe in our porcine model.

[Raman spectroscopic study of microscopic damage on the space structure of DNA with acetic acid].

The character of microscopic damage on the space structure of the herring sperm DNA by wetting treatment of acetic acid with Raman spectroscopic technique was reported. The Raman characteristic frequency and intensity were changed in different degree after wetting treatment on DNA by acetic acid. The results showed that the entire DNA molecule was damaged by acetic acid including backbone phosphodiester groups, deoxyribose and base stacking. The conformation and forms of DNA were changed, hydrogen bond was broken, B-form was modified, both single and double chains were disrupted. Base pairs were damaged. The damage degrees of the base pairs in turn were cytosine, thymine, guanine and adenine.