Construction and functional verification of size-reduced plasmids based on TMP resistance gene dfrB10.

IMPORTANCE: Plasmid size is one of the factors affecting transfection efficacy in most of the molecular genetic research studies. One effective approach for reducing plasmid size is to replace relatively large, conventional antibiotic resistance genes with the short-size dfrB10 gene. The successful construct of a series of dfrB10-based tool plasmids and their functional validation, via comparison with original plasmids, suggest that dfrB10 is a potent drug resistance selection marker. The antibiotic trimethoprim offers convenient usage comparable to that of ampicillin or kanamycin. Additionally, fluorescence analysis has demonstrated the compatibility of TMP with protein expression in various host cells. Based on these findings, TMP-dfrB10 could be an alternative choice for future use in molecular genetic research studies that require miniature plasmids to achieve optimal results.

The Comparison of PCR Kits for the Detection of Erythrocytic Parasites on Filter Paper.

Dried blood spot (DBS) based PCR was considered an inexpensive and feasible method for detecting pathogens in the blood. The DBS carrier filter paper and PCR kits are crucial for accurate diagnosis. We evaluated 4 types of filter papers and 20 PCR kits for DBS samples. The PCR detecting Plasmodium results showed that the minimum detection limit of the 4 filter papers was 1 × 102 parasites/µL, and the positive rates of 20 PCR kits ranged from 0% to 100%. PCR results were satisfactory for detecting Plasmodium falciparum (P. falciparum) and Plasmodium. vivax (P. vivax) in archived DBS samples and Babesia gibsoni (B. gibsoni) in fresh pet DBS samples. Our results provided a useful reference for the detection of blood pathogens with DBS samples and direct PCR, especially for screening the cost-efficacy combination of filter paper and PCR kit in resource-limited areas.

Relationship between Airborne Fungi and Childhood Bronchial Asthma in Huangshi Region / 实用儿科临床杂志

Objective To analyze the relationship between categories,sum and seasonal distribution of airborne fungi and childhood bronchial asthma in Huangshi region.Methods Airborne fungi was investigated through gravitational precipitating method by placing the sample cutter at the 5th floor platform of the surgery department of the First People′s Hospital of Huangshi.Slides were exposed to the air in 24 hours with each day a new slide to be placed.This explosion of slides stayed a whole year from Feb.2007 to Feb.2008.Thus the collected data of fungi were filed,verified and then classified so as to find out the dominant allergic fungi.Multivalent allergen skin tests of fungi were performed on 247 children with bronchial asthma in Huangshi region at the same period and the pattern was explored during invasion season.Results Altogether 365 slides were exposed and 12 667 fungi were collected,which falled to the 22 genres of the 4 sub-categories.And these fungi could be arranged by sum to be alternaria,smut,cladosporium cladosporioides,uredinales,leptosphaeriamaculans and many others including those even without a name.The peak period of fungi distribution in Huangshi city was from Apr to Oct,and it was affected by temperature,wind and rainfall and sunshine.Forty-two point nine one percent were positive reaction to multivalent fungi allergens,of which the hig-hest positive rate to multivalent fungi allergensⅠwas 23.48%.The result showed asthma usually happened during Apr to Aug.Conclusions There were airborne fungi in Huangshi region yearly,and the sensitive season was spring and summer.Dominant fungi were alternaria,ustilaginales and ciadosporium.Forty percent asthma had a close connection to fungi allergens.The attack of children bronchial asthma was corresponded with fungi peak duration.