Objective To analyze the clinical characteristics and prognostic risk factors of helicobacter pylori (Hp) infected patients under 30 years old, and to provide a theoretical basis for the eradication of Hp in young Hp-positive patients under 30 years old. Methods A total of 565 patients with upper gastrointestinal symptoms admitted to our hospital from December 2017 to December 2020 were selected. All patients were Hp positive, and all patients were treated with quadruple eradication therapy of Helicobacter pylori. According to the Hp negative status after treatment, the patients were divided into good prognosis group (Hp negative, n=374) and poor prognosis group (Hp not negative, n=191). A self-made questionnaire was used to analyze the age, gender, familial history of gastrointestinal diseases, life habits (long-term smoking, and drinking), eating habits (irregular diet, and excitant food), DOB baseline value, and treatment compliance of the two groups. Logistic regression was used to analyze the factors that may affect the prognosis of HP positive patients. Results Among the 565 Hp positive patients, 347 were males and 218 were females, with an average age of (23.49±4.29) years, 393 (69.56%) aged 18-24 years old and 172 (30.44%) aged 25-29 years old. The diagnosis results of upper gastrointestinal diseases were 54 cases of gastric cancer (9.56%), 229 cases of peptic ulcer (40.53%), 174 cases of chronic gastritis (30.80%), and 108 cases of reflux esophagitis (19.12%). There were no significant differences in age, sex, family history of gastrointestinal diseases and alcoholism between the two groups (P>0.05). There were statistically significant differences between the two groups in long-term smoking, irregular diet, preference for stimulating food, treatment compliance and baseline value of DOB (P<0.05). The results of logistic regression analysis showed that long-term smoking, poor treatment compliance and high DOB value were independent risk factors affecting the prognosis of Hp positive patients (P<0.05). Conclusion Chronic gastritis and peptic ulcer are the main upper gastrointestinal diseases in Hp-positive young patients under 30 years old. Long-term smoking, poor treatment compliance and high DOB value are independent risk factors affecting the prognosis of patients. Treatment compliance of patients should be improved, and intervention should be strengthened in patients with high DOB value and smoking.

Mucic acid is a hexaric acid that can be biosynthesized by oxidation of D-galacturonic acid, which is the main constituent of pectin. The structure and properties of mucic acid are similar to that of glucaric acid, and can be widely applied in the preparation of important platform compounds, polymers and macromolecular materials. Pectin is a cheap and abundant renewable biomass resource, thus developing a process enabling production of mucic acid from pectin would be of important economic value and environmental significance. This review summarized the structure and hydrolysis of pectin, the catabolism and regulation of D-galacturonic acid in microorganisms, and the strategy for mucic acid production based on engineering of corresponding pathways. The future application of mucic acid are prospected, and future directions for the preparation of mucic acid by biological method are also proposed.
Hexuronic Acids/metabolism* ; Pectins/metabolism* ; Sugar Acids/metabolism*