TraeALDH7B1-5A, encoding aldehyde dehydrogenase 7 in wheat, confers improved drought tolerance in Arabidopsis.

MAIN CONCLUSION: TraeALDH7B1 - 5A , encoding aldehyde dehydrogenase 7 in wheat, conferred significant drought tolerance to Arabidopsis , supported by molecular biological and physiological experiments. Drought stress significantly affects wheat yields. Aldehyde dehydrogenase (ALDH) is a family of enzymes catalyzing the irreversible conversion of aldehydes into acids to decrease the damage caused by abiotic stresses. However, no wheat ALDH member has been functionally characterized to date. Here, we obtained a differentially expressed EST encoding ALDH7 from a cDNA-AFLP library of wheat that was treated with polyethylene glycol 6000. The three full-length homologs of TraeALDH7B1 were isolated by searching the NCBI database and by homolog-based cloning method. Using nulli-tetrasomic lines we located them on wheat chromosomes 5A, 5B and 5D, and named them as TraeALDH7B1-5A, -5B and -5D, respectively. Gene expression profiles indicated that the expressions of all three genes were induced in roots, leaves, culms and spikelets under drought and salt stresses. Enzymatic activity analysis showed that TraeALDH7B1-5A had acetaldehyde dehydrogenase activity. For further functional analysis, we developed transgenic Arabidopsis lines overexpressing TraeALDH7B1-5A driven by the cauliflower mosaic virus 35S promoter. Compared with wild type Arabidopsis, 35S::TraeALDH7B1-5A plants significantly enhanced the tolerance to drought stress, which was demonstrated by up-regulation of stress responsive genes and physiological evidence of primary root length, maintenance of water retention and contents of chlorophyll and MDA. The combined results indicated that TraeALDH7B1-5A is an important drought responsive gene for genetic transformation to improve drought tolerance in crops.

[Risk factors of oral Helicobacter pylori infection among children in two kindergartens in Suzhou and the effects of oral cleaning on reducing oral Helicobacter pylori infection].

OBJECTIVE: This work aimed to identify the risk factors of Helicobacter pylori (H. pylori) infection in preschool children and provide effective measures for the prevention and reduction of the incidence of H. pylori infections. METHODS: A total of 204 children from two kindergartens in Suzhou city were recruited through a questionnaire survey. Risk factors were selected through the single factor paired data χ² test and multiple factor Logistic regression analysis. Oral and gastric H. pylori infections were detected by using H. pylori saliva detection (HPS) and ¹³C-urea breath test (¹³C-UBT). Special toothpaste for H. pylori control was selected for oral cleaning. Oral H. pylori infection rates at 2 months after special toothpaste treatment were examined by using HPS. RESULTS: The high-risk factors of H. pylori infections among preschool children included poor personal hygiene habits, such as the nibbling of fingers and the avoidance of hand-washing before meals, diet, and parent's history of stomach disease. Among the 204 subjects enrolled in this study, 158 (77.45%), 37 (18.14%), and 28 (13.73%) were HPS positive, ¹³C-UBT positive, and HPS and ¹³C-UBT positive, respectively. The incidence of oral H. pylori infections was significantly higher than that of gastric H. pylori infections (P<0.01). The positive rate of infections significantly decreased after special toothpaste treatment (P<0.01). This result indicates that the intervention was effective. CONCLUSIONS: Children must receive education on good eating habits. Individualized dining habits or the use of public chopsticks must be implemented. H. pylori infections must be detected as early as possible. Specific toothpaste for oral cleaning must be selected. These approaches could drastically prevent or reduce the incidence of H. pylori infections among preschool children.

A Clinical Trial on Oral H. pylori Infection of Preschool Children.

GOALS: Over the past twenty years, the existence of oral Helicobacter pylori (H. pylori) infection has been controversial and is still disputed. It proposes that living H. pylori do not exist in the oral cavity. However, the progressive loss of efficacy of standard eradication therapies has made the treatment of H. pylori more challenging than ever due to oral H. pylori infection. We conducted a study to explore the existence of oral H. pylori infection in preschool children. PROCEDURES: A total of 178 children were recruited and evaluated using the saliva H. pylori antigen test (HPS) and the urea breath test (UBT C13) to diagnose oral and stomach H. pylori infections, respectively. The treatments of oral H. pylori infection included toothpaste only, and toothpaste combined with mouth washing morning and night daily for two months. Group A: Children live with parents who have a stomach disease history. Group B: Children live with parents who have no stomach disease history. Group C: Children with toothpaste treatment. Group D: Children with combined toothpaste and mouth rinse treatments. Group E: Control group with no treatments. RESULTS: The positive rate of HPS and C13 were 76.4% and 15.73% in the 95% confidence interval (95% CI) range, respectively, among the 178 children. The positive rate of HPS was significantly higher (p<0.001) with the parents who suffered from stomach H. pylori infections which had been diagnosed by C13. After two-month treatments, Group D and Group E provided 26.87% and 26.44% (95% CI) range efficient rates of the oral H. pylori infection, respectively. The difference between the C, D, and E groups was significant (p<0.001). CONCLUSION: Oral H. pylori exists in the oral cavity of preschool children. The positive rate of HPS was higher with parents suffering from stomach disease, and treatment was effective in reducing oral infection.