Multicenter study of seasonal and regional airborne allergens in Chinese preschoolers with allergic rhinitis.

This study is nationwide multicenter epidemiological research, aimed at investigating the distribution changes and seasonal patterns of various airborne allergens among preschool children with allergic rhinitis (AR) in different regions of China, and analyzing the clinical correlation between sensitization to various airborne allergens and AR symptoms in children. Information on children was collected through standard questionnaires, and total IgE (tIgE) and specific IgE (sIgE) for 11 inhalant allergens were tested. The results showed that dust mites are the primary allergens for preschool AR children (39%). Among pollen allergens, Amb a had the highest positivity rate (8.1%), followed by Art v (7.8%). The sensitization rates for two mites peaked in May (46.9% and 40.6%). Art v peaked in August (21.5%), while Amb a had peaks in May (12.7%) and August (17.8%). The sensitization peaks for various tree pollens mainly occurred in August. In the Eastern monsoon region, the sensitization rate to mites was significantly higher than in the Northwest arid and semi-arid regions; whereas, for pollen allergens, the sensitization rates to Amb a, Pla a, Pin a, Pop d, and Bet v were significantly higher in the Northwest arid and semi-arid regions than in the Eastern monsoon region. The correlation among various tree pollens, specifically between Pla a, Pin r, Pop d, and Bet v was strong (0.63 ~ 0.79), with a cross-overlapping percentage of 53.9%. Children with multiple pollen sensitizations had higher cumulative nasal symptom scores than those negative for pollen (P < 0.01). Children with only pollen sensitization had higher cumulative rhinitis symptom scores than the all-negative group (P < 0.0001) and the mite-only sensitization group [P < 0.05], while the mite-only sensitization group also had higher scores than the all-negative group [P < 0.05], and the group sensitized to both pollen and mites had lower scores than the pollen-only group [P < 0.05]. This study indicates that sensitization to mites and grass pollens exhibits significant regional differences, with grass pollen allergies primarily occurring in autumn, sensitization to pollens in general exhibits a pronounced seasonal pattern. Moreover, pollen sensitization aggravates nasal and ocular symptoms in AR children.

Long-term form and function of neoesophagus after experimental replacement of thoracic esophagus with nitinol composite artificial esophagus.

Attempts were made to observe long-term form and function of neoesophagus with three pigs that survived for more than 42 months after Nitinol composite artificial esophagus replacement. The neoesophagus was shorter in length than resected esophagus (shorten rate 13.9 +/- 3.1) and thinner than normal esophagus (thickness rate 53.8 +/- 5.5). Esophagography and endoscopic findings indicated that the neoesophagus was dilatation of cystic form, and there was not autonomic peristalsis or constrictive motion. Microscopical findings showed that the wall of the neoesophagus consisted of fibrous connective tissue and esophageal mucosa.These results suggest that the long-term neoesophagus is a stratified squamous epithelium cover scar tissue tube. Although it does not have peristaltic function, experimental pigs can survive long-term with the neoesophagus.

Polyester connecting ring improves outcome in nitinol composite artificial esophagus.

In a previous study, we replaced a thoracic esophagus with nitinol composite artificial esophagus. Two major problems of anastomotic leakage and early sloughing of the grafted prostheses were noted. We have developed a new type of nitinol composite artificial esophagus with polyester connecting ring, and in this study, we test the effectiveness of replacing a thoracic esophagus with this new type of tube. We experimented with two groups: with polyester connecting ring (experimental) and without (control). The shedding time of artificial esophagus in the experimental group was significantly delayed compared with the control group (127.2 +/- 51.8 days vs. 27.6 +/- 15.7 days, respectively, p < 0.05). The incidence of the two major postoperative complications in the experimental group was significantly decreased compared with the control group: anastomotic leakage (0% vs. 33.3%, respectively, p < 0.05) and severe neoesophageal stenosis after prostheses sloughing (10% vs. 50%, respectively, p < 0.05). The long-term survival rate (>6 months) in the experimental group was significantly increased compared with the control group (100% vs. 10%, respectively, p < 0.05). These results suggest that the polyester connecting ring improves outcome of replacement of the thoracic esophagus with nitinol composite artificial esophagus.