Investigation on the nasal airflow characteristics of anterior nasal cavity stenosis

We used a computational fluid dynamics (CFD) model to study the inspiratory airflow profiles of patients with anterior nasal cavity stenosis who underwent curative surgery, by comparing pre- and postoperative airflow characteristics. Twenty patients with severe anterior nasal cavity stenosis, including one case of bilateral stenosis, underwent computed tomography (CT) scans for CFD modelling. The pre- and postoperative airflow characteristics of the nasal cavity were simulated and analyzed. The narrowest area of the nasal cavity in all 20 patients was located within the nasal valve area, and the mean cross-sectional area increased from 0.39 cm2 preoperative to 0.78 cm2 postoperative (P<0.01). Meanwhile, the mean airflow velocity in the nasal valve area decreased from 6.19 m/s to 2.88 m/s (P<0.01). Surgical restoration of the nasal symmetry in the bilateral nasal cavity reduced nasal resistance in the narrow sides from 0.24 Pa.s/mL to 0.11 Pa.s/mL (P<0.01). Numerical simulation of the nasal cavity in patients with anterior nasal cavity stenosis revealed structural changes and the resultant patterns of nasal airflow. Surgery achieved balanced bilateral nasal ventilation and decreased nasal resistance in the narrow region of the nasal cavity. The correction of nasal valve stenosis is not only indispensable for reducing nasal resistance, but also the key to obtain satisfactory curative effect.

A School Outbreak of Shigella sonnei Infection in China: Clinical Features, Antibiotic Susceptibility and Molecular Epidemiology.

Objective: To describe the clinical features of infection, and the antibiotic susceptibility of epidemic strains, and investigate plasmid maps and integrons of the isolates from an outbreak of Shigella sonnei infection at an elementary school in southwest China. Study design: Cross-sectional study. Setting: An elementary school and five hospitals in Chengdu in southwest China. Results: There were 1,134 students in the school. 937 (82.6%) students had signs and symptoms. Of the 568 (60.6%, 568/937) hospitalized students, 93.3% 86.8%, 72.4%, and 28.9% of the hospitalized patients had diarrhea, fever, abdominal pain, and vomiting, respectively. S. sonnei strains were isolated from the stool samples of 36.0% (337/937) students. All of the outbreak isolates had the same high-level antimicrobial resistance and plasmid profiles, which were different from that of sporadic strains. All the outbreak S. sonnei isolates were positive for the integrin gene and contained class 2 integron; however, two outbreak isolates contained class 1 and class 2 integrons. Conclusions: Diarrhea, fever, and abdominal pain were the three most common clinical manifestations observed in patients infected with S. sonnei. High-level antibiotic resistance was observed among Shigella species.

Children poisoning in Taiwan.

Poisoning is a well known cause of morbidity and mortality in children. In Taiwan, little information has been published regarding the status of pediatric poisoning exposures. To provide more information on pediatric poisoning exposures for the purpose of poison prevention, a retrospective study was designed and conducted to analyse the data of National Poison Centre (NPC), Taiwan. All telephone inquiries concerning poisoning exposures in those under 19 years of age, received by NPC-Taiwan from July 1985 through December 1993, were included in this study. The age, sex, reason for exposure, route of exposure, substances involved and clinical outcome of those telephone calls were then analyzed. A total of 5,812 inquiries concerning poisoning exposures in children were recorded. Male exposures were more prevalent than females (59%) Vs. 41%) Accidental exposures accounted for 77.7% of the cases and most were exposed by the oral route. Substances most frequently ingested were household products, benzodiazepines and pesticides. The data revealed a mortality rate of 1.4%. Accidental poisoning exposures from household products and drugs remain a significant problem for those younger than 6 years of age. Further education of parents and care takers and the employment of child-resistant containers are needed to prevent cases of pediatric poisoning. Reduction of amphetamine abuse in adolescents is also of major concern and deserves more attention.