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Iron-based composites were reinforced with TiC particulates by in situ synthesis. The microstructure was characterised by transmission electron microscope. The bright field image, dark field image and diffraction pattern of reinforcing particulates and graphite harmful phase were obtained. Meanwhile, the interface between reinforcing particulates and matrix of TiCp/Fe composite material was also observed by scanning electron microscope and transmission electron microscope. The results showed that the calculated lattice constant of reinforcing TiC particulates was 0·41 nm and the calculated lattice constants of graphite were a = 0·282 nm and c = 0·459 nm. The TiC particulates had quadrilateral morphology, and were chemically wetted in Fe matrix without distinct interface product. There was no transition layer at the interface, avoiding pollution of reinforcing particulates. This study provided some details for understanding the bonding interface of in situ metal matrix composites. [ABSTRACT FROM AUTHOR]

Hyper-IgE syndrome ( HIES) is a rare primary immunodeficiency disease characterized by eczema, recurrent staphylococcal aureus skin abscesses, pneumonia with pneumatocele formation, remarkably high serum IgE levels, eosinophilia and involvement of skeleton and connective tissues. Heterozygous signal transducer and activator of transcription 3 ( STAT3) mutations were shown to be the cause of autosomal dominant HIES ( AD- HIES). In this study, we diagnosed nine patients with HIES from 9 unrelated families on the basis of a National Institutes of Health ( NIH) score of ≥40 points, sequenced the STAT3 gene of all nine patients, and quantified Th17 cells in peripheral blood of seven patients by flow cytometry in mainland China. All nine patients had characteristic manifestation of HIES with the range of NIH scores 45-77 points. STAT3 hot mutations V637M or R382W/Q were identified in five patients. We identified two novel heterozygous missense mutations (T620S and R609G) located in Src homology 2 ( SH2) domain in two patients, respectively. In two other patients, no STAT3 mutations were found. Quantified Th17 cell numbers were markedly decreased or absent (0-0.28% of CD4+T cells) in six patients with STAT3 mutations and almost normal (0.53% of CD4+T cells) in one wild-type STAT3 patient compared with healthy controls (0.40-2.25% of CD4+T cells). These results suggest that not all patients with HIES who had NIH scores over 40 points carry STAT3 mutations, those whose Th17 cell numbers strikingly decreased probably had AD- HIES with STAT3 mutations. [ABSTRACT FROM AUTHOR]

Al2O3 particle reinforced Cu–Cr–Zr matrix composite was fabricated through a powder metallurgy plus hot extrusion route, with water atomised Cu–Cr–Zr powder as the starting materials. The electrical sliding wear property was investigated using a pin on disc type wear apparatus in air at room temperature (20°C) compared with the matrix alloy. The results show that arc erosion and mechanical wear were the dominant wear mechanism when sliding under the electrical field. The wear rates increased gradually with increasing electrical current, owing to the augment of electrical erosive degree. Incorporation of Al2O3 reinforcement increased the mechanical properties and then effectively decreased the materials loss induced by both electric arc discharge and adhesion wear. As a result, the Al2O3/Cu–Cr–Zr composite has high electrical sliding wear resistance and would be a promising candidate for the electrical sliding contact fields. [ABSTRACT FROM AUTHOR]

The present work was undertaken to investigate the effect of sliding condition and wear surface state on the dry sliding wear behaviour of SiCp/Cu composite. Three kinds of sliding conditions, namely continuous sliding, interrupted sliding, and interrupted and cleaning sliding were employed. It was observed that a compact mechanically mixed layer (MML) was present on the worn surface of the composite, which effectively decreased the wear loss of the sliding pair. The new running in period of the interrupted tests led to breakage of the MML. Sufficient sliding and entrapment of wear debris in the contact region were two important preconditions for the formation of an MML. Therefore, continuous sliding or long period sliding is favoured to extend the life of this dry tribosystem. [ABSTRACT FROM AUTHOR]

Following the global outbreak of COVID-19, many patients have suffered from multi-system complications and long-term sequelae caused by the virus. Diaphragm dysfunction is an obscure post-COVID-19 symptom. Although a few cases of diaphragm dysfunction caused by COVID-19 infection have been reported abroad, there are no relevant reports in China. Herein, we present two cases of patients with respiratory distress after COVID-19 infection. On admission, dynamic chest radiographs revealed diaphragm dysfunction in these patients. Further investigations including diaphragm ultrasound, neurophysiological examinations, transdiaphragmatic pressure measurements cranial MRI, and antibody testing for autoimmune diseases, were conducted. The final diagnoses were severe myasthenia gravis induced by COVID-19 infection and diaphragmatic nerve and muscle involvement caused by COVID-19 infection. Both patients showed improvement in symptoms after treatment. Therefore, we summarized our case, with a review of the relevant literature to improve the understanding of the disease and to provide clinical evidence for future diagnosis and treatment.

Using the bulk g-C 3 N 4 as a precursor, four g-C 3 N 4 nanosheets were further prepared by ultrasonic, thermal, acid, and alkali exfoliation. The structures of these materials were characterized by various techniques such as X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The synergistical Fenton catalysis of these materials with Cu 2+ was evaluated by using rhodamine B as a simulated organic pollutant. The results showed that there existed a significant synergistical Fenton catalysis between Cu 2+ and g-C 3 N 4 . This synergistic effect can be observed even when the concentration of Cu 2+ was as low as 0.064 mg L -1 . The properties of g-C 3 N 4 strongly influenced the catalytic activity of the Cu 2+ /g-C 3 N 4 system. The coexistent of Cu 2+ and the alkali exfoliated g-C 3 N 4 showed the best catalytic activity. Hydroxyl radicals as oxidizing species were confirmed in the Cu 2+ /g-C 3 N 4 system by electron paramagnetic resonance spectra. The synergistic catalysis may be attributed to the easier reduction of Cu 2+ adsorbed on the g-C 3 N 4 . This study provided an excellent Fenton catalytic system, and partly solved the rapid deactivation of heterogeneous Fenton catalysts caused by the leaching of metal ions.

Graphitic carbon nitride (g-C 3 N 4 ) has attracted a large amount of research, mainly being used as a photocatalyst, but its Fenton-like catalytic performance has been overlooked. In this paper, the dark Fenton-like catalytic performance of g-C 3 N 4 was evaluated by degrading rhodamine B over a wide pH range. The results showed that the g-C 3 N 4 , which was synthesized by conventional urea pyrolysis without any modification, was an efficient metal-free heterogeneous Fenton-like catalyst. The highest activity occurred under a weakly alkaline condition of about pH 10. The experiment of catalyst recycling indicated that g-C 3 N 4 had long-term stability. The reactive oxidizing species of HO·, generated by the g-C 3 N 4 activating H 2 O 2 , was identified by EPR and further supported by a scavenging experiment of HO· using isopropanol as the scavenger. The HNO 3 oxidation of g-C 3 N 4 resulted in catalytic deactivation, implying the catalytic activity originated from the surface reduced groups of g-C 3 N 4 . The structure of synthesized g-C 3 N 4 before and after the HNO 3 oxidation was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and a possible catalytic mechanism was proposed.

Objective: To investigate the functions of FABP5 in the carcinogenesis and development of cervical cancer. Methods: The expression of FABP5 was detected in several cervical cancer cell lines (C33A, Siha, Caski, HeLa and HCC94), 206 cases of cervical cancer tissues with stage Ⅰa2-Ⅱa2 and 40 cases of normal cervical tissues by real-time PCR and Western blotting. Then, the cells were infected with lentivirus-mediated siRNA-targeting FABP5. CCK-8 cell proliferation, colony formation, wound healing and transwell assays were used to investigate the effects of FABP5 on in vitro cell proliferation, migration and invasion. And in vivo xenograft model and lung metastasis model were used to observe the transplanted tumor growth and metastasis in female athymic nude mice. Furthermore, the total protein and RNA were extracted from the primary xenografts to determine the expression levels of FABP5, metalloproteinase-2 and metalloproteinase-9 using Enzyme linked immunosorbent assay (ELISA), real-time PCR and Western blotting. Results: FABP5 expression was found to be significantly unregulated in cervical cancer tissues than that in normal cervical tissues ( P <0.05). Compared with the Siha-NC group and uninfected group, the expression of FABP5 mRNA and protein in Siha-FABP5-RNAi group was significantly inhibited along with the decrease of cell proliferation, colony formation, wound healing and invasion ability. The clone formation rates of Siha cells in uninfected group, Siha-NC group and Siha-FABP5-RNAi group were (84.6±4.5)%, (84.6±5.1)% and (21.2±2.6)%, respectively. Moreover, the transwell assay showed that invasive cells in three groups were (72.8±4.7)/HPF, (72.6±3.3)/HPF and (21.4±2.3)/HPF, respectively. All of the difference was statistically significant ( P <0.05). Furthermore, FABP5 silencing significantly reduced tumor growth and lung metastases in nude mice in vivo ( P <0.001). The subcutaneously xenografted volume in uninfected group, Siha-NC group and Siha-FABP5-RNAi group was (921.4±63.0) mm(3,) (1 021.4±56.0) mm(3) and (139.6±36.0) mm(3,) respectively. The real-time quantitative PCR results showed that the relative expression levels of MMP-2 and MMP-9 mRNA were 1.00±0.10 and 1.00±0.10, 1.00±0.10 and 1.00±0.10 as well as 0.34±0.13 and 0.38±0.17 in xenografted tumor tissues of uninfected group, Siha-NC group and Siha-FABP5-RNAi group, respectively. MMP-2 and MMP-9 was significantly downregulated after FABP5 inhibition( P <0.05). Additionally, the protein expression trend of MMP-2 and MMP-9 in three groups was consistent with the mRNA levels. Conclusion: FABP5 might promote the carcinogenesis and metastasis of cervical cancer via up-regulating MMP-2 and MMP-9.

Objective: Community acquired pneumonia (CAP) is a common pulmonary infectious disease. Glucocorticoids (GCS) as one of the most powerful anti-inflammation drugs, are still the most controversial adjuvant therapy in treating CAP. Which sub-groups of CAP patients would benefit from GCS is a debating topic. Our aim of this study is to find the indications for GCS in treating adult CAP patients by using meta-analysis., Method: "Steroids, glucocorticoids, corticosteroids, hydrocortisone, prednisone, cortisol, methylprednisolone, dexamethasone"and"community-acquired pneumonia"were used as key words both in Chinese and English to search all published literature in Pubmed, EMBASE MEDLINE, Cochrane, CNKI and Wanfang Database until March 2015., Results: All 840 articles were reviewed, and 11 high quality randomized clinical trials involving 1942 adult CAP patients were included in this meta-analysis. Using GCS did not significantly reduce mortality in all CAP patients (OR=0.68, 95%CI 0.46-0.99, P=0.04). But in the subgroup analysis, patients with severe CAP benefited from GCS treatment (OR=0.35, 95%CI 0.17-0.75, P=0.007). GCS also increased the risk of hyperglycemia (OR=1.99, 95%CI 1.50-2.65, P<0.000 01)., Conclusion: RESULTS from this meta-analysis suggested that GCS should only be rigorously used in severe CAP patients.