[Variation and interaction mechanism between active components in Rheum officinale and rhizosphere soil microorganisms under drought stress].

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.

Application of data mining methods to improve screening for the risk of early gastric cancer.

BACKGROUND: Although gastric cancer is a malignancy with high morbidity and mortality in China, the survival rate of patients with early gastric cancer (EGC) is high after surgical resection. To strengthen diagnosing and screening is the key to improve the survival and life quality of patients with EGC. This study applied data mining methods to improve screening for the risk of EGC on the basis of noninvasive factors, and displayed important influence factors for the risk of EGC. METHODS: The dataset was derived from a project of the First Hospital Affiliated Guangdong Pharmaceutical University. A series of questionnaire surveys, serological examinations and endoscopy plus pathology biopsy were conducted in 618 patients with gastric diseases. Their risk of EGC was categorized into low and high risk of EGC by the results of endoscopy plus pathology biopsy. The synthetic minority oversampling technique (SMOTE) was used to solve imbalance categories of the risk of EGC. Four classification models of the risk of EGC was established, including logistic regression (LR) and three data mining algorithms. RESULTS: The three data mining models had higher accuracy than the LR model. Gain curves of the three data mining models were convexes more closer to ideal curves by contrast with that of the LR model. AUC of the three data mining models were larger than that of the LR model as well. The three data mining models predicted the risk of EGC more effectively in comparison with the LR model. Moreover, this study found 16 important influence factors for the risk of EGC, such as occupations, helicobacter pylori infection, drinking hot water and so on. CONCLUSIONS: The three data mining models have optimal predictive behaviors over the LR model, therefore can effectively evaluate the risk of EGC and assist clinicians in improving the diagnosis and screening of EGC. Sixteen important influence factors for the risk of EGC were illustrated, which may helpfully assess gastric carcinogenesis, and remind to early prevention and early detection of gastric cancer. This study may also be conducive to clinical researchers in selecting and conducting the optimal predictive models.

Indoor air pollution and human ocular diseases: Associated contaminants and underlying pathological mechanisms.

People spend a long time indoors, especially young children. The risk of indoor pollution on human health is one of the current hotspots in environmental and public health. The human ocular surface is highly susceptible to indoor environment quality. Epidemiological data have linked human ophthalmological disorders with exposure to indoor pollution. In this review, we summarized the adverse impacts of indoor pollution on the human ocular surface. Several studies demonstrated that indoor contaminants including particulate matter, volatile/semi-volatile organic compounds, heavy metals, and fuel combustion and cigarette smoke exposure were associated with the incidence of human dry eye, conjunctivitis, glaucoma, cataracts, age-related macular degeneration, and keratitis. In addition, toxicological investigations revealed that indoor pollution-induced induced chronic inflammation, oxidative damage, and disruption of tight junctions are the main underlying pathological mechanisms for ocular surface diseases. Taken together, this review may expand the understanding of pollution-induced eye disorder and highlight the importance of reducing associated contaminants to decrease their detrimental effects on human eyes.

Effects of Nickel at Environmentally Relevant Concentrations on Human Corneal Epithelial Cells: Oxidative Damage and Cellular Apoptosis.

Nickel (Ni) is ubiquitous in the environment and evidence has suggested that Ni can cause ocular surface inflammation, especially in fine particulate matter and personal products. Continuous daily exposure to Ni-containing dust may adversely impact the human cornea, whereas the underlying mechanism of this phenomenon remains not fully understood. Here, human corneal epithelial cells (HCEC) were employed to analyze the toxicity of Ni via detections of cell morphology, cell viability, reactive oxygen species production, cell apoptosis rate, and apoptotic gene expression levels after exposure for 24 h to uncover the damage of Ni to the cornea. A concentration-dependent inhibition of HCECs' viability and growth was observed. In particular, Ni at 100 µM significantly decreased cell viability to 76%, and many cells displayed an abnormal shape and even induced oxidative damage of HCEC by increasing ROS to 1.2 times, and further led to higher apoptosis (24%), evidenced by up-regulation of apoptotic genes Caspase-8, Caspase-9, NF-κB, IL-1ß, and Caspase-3, posing a risk of dry eye. Our study suggested that Ni induces apoptosis of HCEC through oxidative damage. Therefore, Ni pollution should be comprehensively considered in health risks or toxic effects on the ocular surface.

[Effect of endothelial progenitor cell on hematopoietic reconstitution in allogeneic hematopoietic stem cell transplantation mouse model].

OBJECTIVE: To examine the effects of endothelial progenitor cell (EPC) on hematopoietic reconstitution in allogeneic hematopoietic stem cell transplantation (allo-HSCT) mouse model. METHODS: Allo-HSCT mouse model was established with condition of BU/CY, in which C57BL/6 (H-2b) and BALB/c (H-2d) mice were used as donors and recipients respectively. Recipients were randomly divided into 4 groups: untreated group, BU/CY condition group, bone marrow transplantation (BMT) group and transplantation of BM cells combined with EPCs (combined transplantation) group. The pathological changes of BM cells following transplantation were dynamically observed. Changes of BM sinusoidal endothelium and angiogenesis were observed by MECA-32 antibody immunohistochemical staining. The proportion of intramedullary stem and progenitor cells and serum cytokines were analyzed by flow cytometry. The numbers of peripheral blood cells were also counted. RESULTS: (1) Injuries of BM hematopoietic tissue, sinusoidal endothelium and vascular were less severe in combined transplantation group than of BMT group. (2) EPC infusion significantly increased BM hematopoietic stem cells 21 days after transplantation. The percentage of BM hematopoietic stem cells in combined transplantation group peaked on day +14, which was higher than of BMT group (0.1743 vs 0.0787) (P<0.05). The continuously increased percentage of BM hematopoietic progenitor cells in combined transplantation group was significantly higher than in BMT group on day +21 (0.4550 vs 0.3905) (P<0.05). (3) The number of peripheral white blood cells in combined transplantation group was always higher than of BMT group, which reached the peak on day +14 (0.74×109/L to 0.47×109/L) (P<0.05). The peak number of peripheral blood platelets on day +14 in combined transplantation group was significantly higher than of group BMT (1228.9×109/L to 977.12×109/L) (P<0.05). CONCLUSION: Allo-HSCT combined with EPC infusion accelerated hematopoietic reconstitution compared with BMT alone in allo-HSCT mouse model.

[Effects of liver sinusoid endothelial cell injury in mouse hepatic veno-occlusive disease].

This study was purposed to investigate the role of monocrotaline-inducing mouse liver sinusoid endothelial cell (SEC) injury in hepatic veno-occlusive disease. BALB/c mice were randomly divided into 2 groups: control group and monocrotaline group, mice were orally administrated with normal saline or monocrotaline with concentration of 200 mg/kg at days 0, 1, 2, respectively. At days 3, 4, 6, 8 and 10 after oral administration with normal saline or monocrotaline, the liver function (ALT, TBIL, AKP) and liver index were examined, and the percentage of activated platelets were detected by flow cytometry. The SEC, vascular endothelial cells and hepatic fibrosis were observed by staining with hematoxylin-eosin and Masson. Transmission electron microscopy was used to observe sinusoidal endothelial cell damage and platelet adhesion. The results showed that compared with control group, mice in monocrotaline group were characterized by severe damage of SEC, numbers of platelet aggregation and adhesion, central number and sinusoidal fibrosis. The percentage of activated platelets and liver index increased (P < 0.05). The characterization of portal hypertension was presented later, such as dysfunction of liver and ascites. It is concluded that SEC injury induced by monocrotaline may be the first step of hepatic veno-occlusive disease, and this kind of SEC injury is self-limiting, but fibrosis is always observed.