Selenium (Se) is one of the essential trace elements that plays a biological role in the body, mainly in the form of selenoproteins. Selenoproteins can be involved in the regulation of oxidative stress, endoplasmic reticulum (ER) stress, antioxidant defense, immune and inflammatory responses and other biological processes, including antioxidant, anti-inflammation, anti-apoptosis, the regulation of immune response and other functions. Over-loading or lack of Se causes certain damage to the body. Se deficiency can reduce the expression and activity of selenoproteins, disrupt the normal physiological function of cells and affect the body in antioxidant, immunity, toxin antagonism, signaling pathways and other aspects, thus causing different degrees of damage to the body. Se intake is mainly in the form of dietary supplements. Due to the important role of Se, people pay increasingly more attention to Se-enriched foods, which also lays a foundation for better research on the mechanism of selenoproteins in the future. In this paper, the synthesis and mechanism of selenoproteins, as well as the role and mechanism of selenoproteins in the regulation of diseases, are reviewed. Meanwhile, the future development of Se-enriched products is prospected, which is of great significance to further understand the role of Se.

Selenium (Se) is an essential trace element in the body. It is mainly used in the body in the form of selenoproteins and has a variety of biological functions. Intestinal diseases caused by chronic inflammation are among the most important threats to human health, and there is no complete cure at present. Due to its excellent antioxidant function, Se has been proven to be effective in alleviating intestinal diseases such as inflammatory bowel diseases (IBDs). Therefore, this paper introduces the role of Se and selenoproteins in the intestinal tract and the mechanism of their involvement in the mediation of intestinal diseases. In addition, it introduces the advantages and disadvantages of nano-Se as a new Se preparation and traditional Se supplement in the prevention and treatment of intestinal diseases, so as to provide a reference for the further exploration of the interaction between selenium and intestinal health.

BackgroundSputum eosinophil and fractional exhaled nitric oxide (FeNO), noninvasive biomarkers of local eosinophilic airway inflammation, can be used to assess asthma outcome. Nevertheless, the clinical application of the association between FeNO and sputum eosinophil is controversial. The aim of the study was to investigate the predictive relationship between FeNO and sputum eosinophil in uncontrolled asthmatic patients and the correlation between sputum eosinophil and FeNO in bronchial reversibility and bronchial hyperresponsiveness (BHR).MethodsA total of 69 uncontrolled asthmatic patients were included in the study. All patients underwent a clinical assessment on the same day as follows: FeNO, spirometry with BHR or bronchodilator reversibility test and induced sputum in turn. Eosinophilic airway inflammation was defined as sputum eosinophil percentage (≥2.5%)/FeNO level (≥32 parts per billion [ppb]).ResultsFeNO level and sputum neutrophilic percentage were higher in the sputum eosinophilia group compared to those without (49 versus 27, p=0.011; 71.12 versus 87.67, p=0.012, respectively). Sputum eosinophil percentage was higher with raised FeNO level compared to those without (10.3% versus 2.75%, p=0.03). A significant correlation was observed between sputum eosinophil percentage and FeNO level (r=0.4016; p=0.0006). There were no significant relationships between sputum eosinophilic percentage and provocative dose (PD20)/ΔFEV1 (improvement in a forced expiratory volume in 1 second [FEV1] after 400μg of salbutamol), FeNO levels and PD20/ΔFEV1. The FeNO level of 35.5 ppb was effective in assessing sputum eosinophilia, with a receiver operating characteristic area under curve (AUC) of 0.707 (p=0.011; 95% confidence interval [CI] 0.573–0.841), and 4.36% was the best diagnostic cutoff value of sputum eosinophil percentage for the FeNO level of 32 ppb (AUC 0.721; 95% CI 0.59–0.852).ConclusionFeNO level can accurately detect eosinophilic asthma but has limited value to assess noneosinophilic asthma in uncontrolled stage. Further studies are required to validate the use of FeNO level to determine an optimal cutoff for sputum eosinophilia that could be used in clinical practice.

When performing femur fracture reduction surgery, both the patient and surgeon are exposed to a great amount of radiation, which is harmful to their health. In order to reduce such radiation from the usage of an image intensifier, various robots have been proposed for femur fracture reduction surgery. Most of these robots are based on serial architecture. The low transportable load and poor accuracy are both inherent in serial robots, which makes them inappropriate for femur fracture reduction. Some parallel robots based on the 'Stewart platform' have also been developed for femur fracture reduction, but their restricted workspace limits their applicability and accessibility. To balance the accuracy, payload and workspace, a new robot system is reported in this paper. The proposed robot system consists of a 2-d.o.f. device and a 6-d.o.f. hybrid robot. The 2-d.o.f. device is used for distraction, which requires a very large force. The hybrid robot is used to manipulate a bone fragment for alignment and fixation purposes. The hybrid robot possesses the characteristic of a Cartesian coordinate robot; all the movements of the actuators are linear, which makes its motion smooth for low-speed fracture reduction procedures. The forward and inverse kinematics of the proposed robot are analyzed. The analysis is much simpler compared to traditional serial manipulators and parallel Stewart platform robots. A prototype of the proposed system is made using a rapid fabrication system called Objet. The positioning accuracy of the proposed system is measured using a coordinatemeasuring machine. The results show that the algorithms presented in this paper for the control of the robot are accurate and robust.