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Background and objective: Nerve growth factor (NGF)/tyrosine kinase receptor A (TrkA) signalling may play an important role in the pathogenesis of asthma, and SH2-Bβ, a TrkA-binding protein, modulates the NGF signalling pathway. In this study, SH2-Bβ expression in alveolar macrophages (AM) in guinea pig BAL fluid and its role in asthma pathogenesis through the NGF–TrkA signalling pathway were investigated. Methods: Guinea pigs were randomized into five groups: control, a model of asthma, anti-SH2-Bβ antibody treatment, anti-NGF antibody treatment and anti-TrkA antibody treatment. The asthmatic model was established in guinea pigs by inhalation of ovalbumin. Specific anti-SH2-Bβ, anti-NGF and anti-TrkA antibodies were administered and AM were isolated from BAL fluid to assess SH2-Bβ expression using an immunofluorescence assay. SH2-Bβ and TrkA protein expression were determined by western blotting, IL-1β and IL-4 levels in the BAL fluid supernatants were determined by ELISA, and pathological changes in the bronchi and lung tissues were examined by HE staining. Results: Lymphocyte, eosinophil and total inflammatory cell numbers in BAL fluid were significantly higher in the asthma model group than in the other groups ( P < 0.01). NGF expression in the asthma model group was significantly higher than that in the PBS control group ( P < 0.01). SH2-Bβ was expressed in AM of control animals and expression was significantly higher in the asthma model than in the other groups ( P < 0.01). TrkA protein expression was significantly higher in the asthma model group than in the PBS group ( P < 0.01), and treatment with anti-NGF antibody resulted in significant reduction of TrkA expression ( P < 0.01). Conclusions: SH2-Bβ is expressed in AM of normal guinea pigs, and SH2-Bβ may participate in asthma pathogenesis through the NGF–TrkA signalling pathway. [ABSTRACT FROM AUTHOR]

It is significant to perform bonding state detection of explosive clad structure to avoid serious accidents. Due to the complexity of its bonding interface, constructing the detection index which is sensitive to the change of the bonding state has turned into a challenging task. Therefore, a novel method based on the Hilbert envelop energy ratio of mono-model signals is proposed for this task. Benefiting from the advantage of only related with intrinsic property parameters such as damping ratios, natural frequencies and principal modes; the Hilbert envelope energy ratio of arbitrary two order model signals from impulse vibration response can reflect the inherent property of the multi-degree-of-freedom (MDOF) system. In addition, it has been found that the bonding state of explosive clad structure is mainly related with the structural damping ratio. Introduce the general characteristic of MDOF system into explosive clad structure, the detection index based on the Hilbert envelope energy ratio of mono-model signals is constructed for the bonding state detection of explosive clad structure. The proposed method is applied to the bonding state detection of explosive clad pipes to validate its robustness and effectiveness. Compared with the detection method based on optimized dual-tree complex wavelet transform (ODTCWT) and time entropy index proposed by the authors in previous research, the results indicate that the robustness and effectiveness of the proposed method in this paper is more superior to that of the detection method based on ODTCWT and time entropy index. [ABSTRACT FROM AUTHOR]

Background Helicobacter pylori (H. pylori) infection induced precancerous lesions of gastric mucosa mostly in adulthood. However, it is debatable whether these pathological changes could also occur in children. Objective To investigate the relationship between H. pylori infection and precancerous lesions of gastric mucosa in children hospitalized due to upper gastrointestinal symptoms in central plain area of China. Methods A total of 1 015 children under the age of 18 years old were enrolled. These children attended the People's Hospital of Zhengzhou University for upper gastrointestinal symptoms such as abdominal pain, bloating, nausea, vomiting, hiccups, and acid reflux from August 2018 to July 2021. All children underwent gastroscopy, from which gastric mucosal biopsy tissues were taken for rapid urease test and histopathological examination. The clinical and pathological data of the patients were collected retrospectively. The children were divided into infected and uninfected groups according to H. pylori infection status. The age, sex, endoscopic diagnosis, and H. pylori infection rate were compared between children in infected and uninfected groups. The incidence of precancerous lesions of gastric mucosa, inflammatory activity and the degree of inflammatory cell infiltration were compared between infected and uninfected groups, meanwhile these tests were also compared in children of different age groups. Results Among the 1 015 children, 854 (84.14%) were infected with H. pylori and 161 (15.86%) were not infected. H. pylori-infected children were significantly older than those of non-infected subjects (P