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The discovery of a two-dimensional electron gas (2DEG) at the [Formula: see text] interface has set a new platform for all-oxide electronics which could potentially exhibit the interplay among charge, spin, orbital, superconductivity, ferromagnetism and ferroelectricity. In this work, by using angle-resolved photoemission spectroscopy and conductivity measurement, we found the reduction of 2DEGs and the changes of the conductivity nature of some ferroelectric oxides including insulating Nb-lightly-substituted [Formula: see text], [Formula: see text] (BTO) and (Ca,Zr)-doped BTO across paraelectric-ferroelectric transition. We propose that these behaviours could be due to the increase of space-charge screening potential at the 2DEG/ferroelectric regions which is a result of the realignment of ferroelectric polarisation upon light irradiation. This finding suggests an opportunity for controlling the 2DEG at a bare oxide surface (instead of interfacial system) by using both light and ferroelectricity.

The quantum spin Hall (QSH) effect is widely studied as a novel quantum state in condensed matter physics over the past decade. Recently, it is predicted that the transition metal pentatelluride XTe5 (X = Zr, Hf) has a large bandgap in its bulk form and a single layer of XTe5 is a QSH insulator candidate. However, the topological nature of the bulk material is still under debate because it is located close to the phase boundary of a strong topological insulator and a weak topological insulator (WTI). Here, using angle-resolved photoemission spectroscopy and scanning tunneling microscopy (STM)/scanning tunneling spectroscopy, we systematically studied the electronic structures of bulk HfTe5. Both the large bulk bandgaps and conductive edge states in the vicinity of the step edges in HfTe5 were observed, strongly suggesting a WTI phase in bulk HfTe5. Moreover, our STM experiment for the first time reveals the bulk band bending due to the broken symmetry near the step edge, making it an ideal platform for studying the development of edge states in the WTI and QSH insulator. [ABSTRACT FROM AUTHOR]

Objective: The aim is to analyze the fracture risk in rheumatic patients by fracture risk assessment tool (FRAX), which is recommended by World Health Organization (WHO), so that we can prevent the occurrence of osteoporotic fracture earlier. Methods: Totally 617 participants, 204 out-patients with rheumatism, 204 in-patients with rheumatism and 209 healthy controls, from March to October in 2018 of Fourth Medical Center of PLA General Hospital, Jishuitan Hospital and China-Japan Friendship Hospital, were enrolled in this study. The probability of hip fracture (PHF) and major osteoporotic fracture (PMOF) in 10 years with FRAX were compared, and the differences between taking sleroids or not and with or without bone mass density (BMD) of femoral neck were evaluated. Correlation analysis was conducted between PHF, PMOF and clinical information, including age, disease duration, gender, steroid usage, osteocalcin, P1NP and β-crosslaps. Results: There was no significant difference in PMOF within 10 years (3.455±2.690 vs 2.973±2.149 vs 3.323±1.828) among the three groups ( P> 0.05), but the PHF (0.986±1.619 vs 0.515±0.873 vs 0.149±0.311) was different ( P< 0.05). PHF and PMOF increased gradually with age. PMOF of patients without glucocorticoid therapy in 10 years was lower than that of patients with glucocorticoid (3.554±2.584 vs 2.857±2.238, P< 0.05). There is no difference between the results of FRAX calculated with BMD or not (3.012±2.231 vs 3.207±2.601, P> 0.05). PHF and PMOF were positively correlated with age, course of disease, glucocorticoid use and osteocalcin level, while PHF was negatively correlated with TP1NP among in-patients. Conclusion: The prevalence of 10-year hip fracture calculated by FRAX in rheumatism patients is higher than that of healthy group. FRAX can be used to calculate fracture risk without BMD. Combination of FRAX and bone turnover markers may be more effective in prediction of osteoporotic fracture in rheumatic patients.

Objectives: Death risk factors of patients with antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) were explored by the analysis of clinical characteristics of AAV patients, as to provide the basis for early diagnosis and treatment, and reduction of mortality and also improvement of prognosis. Methods: A retrospective study was conducted in patients with AAV which were admitted to this hospital from November 2003 to February 2017, by the contrasts of the similarities and differences of clinical characteristics between the death group and non-death group, for explore the risk factors of death. Results: (1) A total of 66 patients with AAV were included in this study, in which 20 were died (male/female was 12/8), and 46 were still alive, with a total mortality rate of 30.3%.(2)The average age of disease onset in the death group was (67±13) years, which was significantly higher than that of the control group (55±18, P =0.009). (3)The mean value of vasculitis damage index (VDI) in the death group was (6.4±2.5), which was significantly higher than that in the non-death group (4.4±2.5, P =0.006). (4)As to multiple organs involvements among the heart, lung, kidney, gastrointestinal tract, central nervous system and other organs, the proportion of three or more organs involvement in the death group was 85% (17/20), which was significantly higher than that in the control group 47.8%(22/46), P =0.004 8.The incidence of heart murmurs, recent premature beats, aortic insufficiency, chronic heart failure/cardiomyopathy, and massive hemoptysis were significantly higher than those in the control group ( P <0.05). (5) The incidence of infection in the death group (55%) was significantly higher than that in the control group (28.3%, P =0.038). Conclusion: An onset age of more than 65, multiple organs involvement, especially the occurrence of massive hemoptysis, heart valve diseases, heart failure and other cardiovascular involvements, increased VDI and combination of infections are the risk factors of death in AAV patients.

Objective: To investigate the clinical features of patients with antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), and to explore the disease activity of AAV patients and the relationship with prognosis., Methods: The clinical data of 46 cases of AAV patients in the First Affiliated Hospital of PLA General Hospital were analyzed retrospectively.The clinical and laboratory features of each clinical subtype were compared.The disease activity of AAV and the relationship between disease activity and prognosis were evaluated., Results: Among the 46 patients with AAV, 24 were male, and 22 were female, with the average age of 56±18.Among the subtypes of AAV, the number of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) were 22, 17 and 4 respectively, while the positive rate of ANCA are 72.7%, 88.2% and 50.0% respectively.For GPA, the results of ANCA were mainly C-ANCA or ANCA directed toward proteinase-3 (PR3), and for MPA, the results of ANCA were mainly P-ANCA or ANCA directed toward myeloperoxidase (MPO). Upper and lower respiratory disease, renal involvement and non-deformity arthropathy were the common clinical manifestations of all primary AAV subtypes.Epistaxis, nasal blood scab, saddle nose, pulmonary nodule and intrapulmonary cavities were the characteristic manifestations of GPA, while rapid progress of renal failure was prominent in MPA.Whatever their ANCA results, there were no significant differences between each other as to system-organ involvements and laboratory indexes.Seven patients (15.2%) died during hospitalization or in follow-up visits.Serious involvements of heart, lung, kidney, and complicated with infections were the main risk factors of death in AAV patients., Conclusions: Upper and lower respiratory involvements and kidney diseases are the primary manifestations of AAV patients.ANCA results are irrelevant with disease activity and system-organ involvements.Serious involvements of heart, lung, kidney, and complicated with infections are the main risk factors of death in AAV patients.

We examined the expression of peripheral blood natural killer T (NKT) cells in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients and predicted its efficacy after pegylated interferon α-2a (Peg-INFα-2a) therapy. Sixty-three cases of HbeAg-positive CHB inpatients and outpatients, treated in the Third Xiangya Hospital of Central South University from January to December 2010, were administrated Peg-INFα-2a 18 myriad international unit intramuscularly once per week for 48 weeks. The number of peripheral NKT cells, 5 quantitative indicators of hepatitis B, and hepatitis B virus DNA capacity were detected at each time point. Forty-eight weeks after Peg-INFα-2a treatment, 26 HBeAg-positive CHB patients exhibited significant effects, 21 cases exhibited effects, and 16 cases showed no effects. The ratio of peripheral blood NKT cells in T lymphocytes before and 4, 8, and 12 weeks after treatment in the significant effect group was significantly increased compared to the effect group and no effect group (P < 0.01); at the 48th week of treatment and 24 weeks after the drug was withdrawn, NKT cell expression in the significant effect group was significantly higher than that in the effect group (t = 32.0, P < 0.01; t = 27.6, P < 0.01, respectively). A total of 27 patients showed HBeAg seroconversion until the 24th week after drug withdrawal. During treatment with Peg-INFα-2a in HBeAg-positive CHB patients, expression of peripheral blood NKT cells could be used to predict efficacy.

Spontaneously hypertensive (SHR), Wistar-Kyoto (WKY), and Sprague-Dawley (SD) rats at the ages of 4, 8, 12, 16 and 24 weeks were used to examine the effects of age on the density of endothelin-1 (ET-1) binding sites in aortic smooth muscle cells and systolic blood pressure (SBP). The SBP of the 3 different rat strains was measured, and the maximum binding value (Bmax) and dissociation constant (Kd) of ET-1 binding sites in smooth muscle cells of the thoracic aorta were determined. The results showed that the SBP and Bmax values of SHR, WKY and SD rats increased with age; the SBP and Bmax value at each corresponding age were significantly higher in SHR than in WKY and SD rats, however, there was no significant difference between WKY and SD rats. The relationship of age vs SBP, age vs Bmax, and Bmax vs SBP showed significantly positive correlation in all 3 rat strains. The regression line in the Bmax of endothelin binding sites against SBP in the 3 different rat strains presented a similar slope. These results indicate that SBP, which increased with age, could be related to an increased density of ET-1 binding sites on vascular smooth muscle cells in these 3 different rat strains.

Endothelin-1 (ET-1), which is secreted from vascular endothelial cells, is not only a potent vasoconstrictor but also a vascular smooth muscle cell growth factor. The direct effect of ET-1 on vascular smooth muscle cells, mediated via its specific receptor may therefore play an important role in hypertension and atherosclerosis. Our previous studies indicated that ET-1 secretion from cultured aortic endothelial cells from spontaneously hypertensive rats (SHRs) at the prehypertensive stage (4 weeks old) was not significantly different from that of cells from age-matched Wistar-Kyoto (WKY) rats. In this study, the binding of ET-1 to cultured aortic smooth muscle cells from SHRs and WKY rats was studied. Using tissue explant techniques, rat aortic smooth muscle cells from SHRs and age-matched WKY rats of different ages (4 and 24 weeks old) were successfully cultured in vitro. The maximum binding capacity (Bmax) and binding affinity (Kd) of ET-1 to cultured aortic smooth muscle cells were evaluated by a receptor-binding assay. The data revealed that the affinity of ET-1 binding to smooth muscle cells was similar in all 4 groups of experimental rats. However, the Bmax of cultured smooth muscle cells from 24-week-old SHRs was 2.5 times higher than of smooth muscle cells from age-matched WKY rats (8.64 +/- 0.72 vs 3.69 +/- 0.10 fmol/10(6) cells) and 1.5 times higher than in aortic smooth muscle cells from 4-week-old SHRs (8.64 +/- 0.72 vs 5.36 +/- 0.36 fmol/10(6) cells). These results suggest that hypertension in SHRs may be related to a high density of ET-1 receptors on arterial smooth muscle cells.

Experiments are described supporting the proposition that the assembly of stress fibers in non-muscle cells and the assembly of myofibrils in cardiac cells share conserved mechanisms. Double staining with a battery of labeled antibodies against membrane-associated proteins, myofibrillar proteins, and stress fiber proteins reveals the following: (a) dissociated, cultured cardiac myocytes reconstitute intercalated discs consisting of adherens junctions (AJs) and desmosomes at sites of cell-cell contact and sub-sarcolemmal adhesion plaques (SAPs) at sites of cell-substrate contact; (b) each AJ or SAP associates proximally with a striated myofibril, and conversely every striated myofibril is capped at either end by an AJ or a SAP; (C) the invariant association between a given myofibril and its SAP is especially prominent at the earliest stages of myofibrillogenesis; nascent myofibrils are capped by oppositely oriented SAPs; (d) the insertion of nascent myofibrils into AJs or into SAPs invariably involves vinculin, alpha-actin, and sarcomeric alpha-actinin (s-alpha-actinin); (e) AJs are positive for A-CAM but negative for talin and integrin; SAPs lack A-CAM but are positive for talin and integrin; (f) in cardiac cells all alpha-actinin-containing structures invariably are positive for the sarcomeric isoform, alpha-actin and related sarcomeric proteins; they lack non-s-alpha-actinin, gamma-actin, and caldesmon; (g) in fibroblasts all alpha-actinin-containing structures are positive for the non-sarcomeric isoform, gamma-actin, and related non-sarcomeric proteins, including caldesmon; and (h) myocytes differ from all other types of adherent cultured cells in that they do not assemble authentic stress fibers; instead they assemble stress fiber-like structures of linearly aligned I-Z-I-like complexes consisting exclusively of sarcomeric proteins.

The teratogenic potential of 1,1,3,3-tetrabutylurea (TBU) was evaluated in the Crl:CD(SD)BR rat. Doses of 25, 50 or 100 mg TBU/rat/day in 0.5 ml dimethyl phthalate were applied to the shaven dorsal skin on days 6-15 of gestation, the day on which a sperm-positive vaginal smear was present being designated day 1. The rats were killed 1 day before natural delivery and the foetuses were examined for external development, structure and integrity of internal tissues and organs, and skeletal development. No maternal effects were seen in rats exposed to 25 mg TBU, but skin irritation and a reduction in maternal body-weight gains were seen in rats treated with either 50 or 100 mg/day, the effects being more pronounced in the 100-mg/day group. In the latter group, the number of pregnancies maintained was reduced and the number of resorptions per litter, calculated only on the litters with resorptions, was increased. Foetuses derived from the females treated with 100 mg/day were slightly smaller than the controls but were structurally normal. The outcome of pregnancy was unaltered in rats given either 25 or 50 mg TBU/day. No increase in malformed foetuses was observed in any of the test groups. Under the conditions of this study, TBU was not teratogenic when applied dermally to rats at doses up to 100 mg/day.