ERIC-PCR has been widely used as genomic fingerprinting technology for classification and identification of bacterial isolates. Recently, it has been used by some labs to characterize bacterial mixtures. However, there are still disputes regarding the mechanism of product formation in ERIC-PCR. We cloned and sequenced the 1. 1kb major band of the ERIC-PCR fingerprint of E. coli K-12 strain MG1655, the strain used for whole genome sequencing, and found that the band consisted of 3 different DNA fragments with one fragment the most abundant (93 out of 95 clones, i. e. 97. 89%). Sequence analysis showed that two of the three fragments amplified from a chromosomal region where one ERIC element exist either upstream or downstream, while one fragment amplified from a region where no ERIC element was found. It was thus postulated that ERIC-PCR is not an absolutely random amplified PCR technique, especially when it is applied to those genomes containing ERIC elements.

Objective To evaluate antibacterial activities of Cefoperazone-Sulbactam upon gram negative bacilli,and compare the differences in susceptibility between two different concentrations of Cefoperazone-Sulbactam combination disc.Method A total of 381 strains of commonly occurred gram negative bacilli were found from 2nd Affiliated Hospital of Zhejiang University School of Medicine,Zhejiang Provincial People's Hospital,The Third Hospital of Hangzhou and Hangzhou Hospital of Traditional Chinese Medicine respectively.Susceptibility test was conducted by K-B method using 75 μg/disc Cefoperazone plus with 75 μg/disc Sulbactam(150 disc)and 75 μg/disc Cefoperazone with 30 μg/disc Sulbactam(105 disc),respectively.Meanwhile the minimal inhibitory concentration(MIC)of Cefoperazone-Sulbactam was determined by standard agar dilution.The data were analyzed by using WHONET 5.4 and SPSS.Results Disc diffusion method was carried out to detect the antibacterial activities upon Escherichia coli,Klebsiella pneumonia,Pseudomonas aeruginosa and Acinetobacter baumannii,using 105 disc and 150 disc,respectively.The data indicated that consistency rates between these two different discs were 26.3%,79.2%,83.7%and 33%,respectively.The k-related sample test was performed by using SPSS version 10.0 and shown that the P value was less than 0.05.Upon those organisms mentioned above,the consistency rates between the antibacterial activities of 105 disc and those of agar dilution were 77.8%,89.6%,70.9%and 77%,respectively.When it was going to compare agar dilution vs.150 disc upon the susceptibility of those organisms the consistency rates were 27.3%,79.2%,61.6%and 30%,respectively.Compared with agar dilution,the error rates of those two different concentration discs revealed that the false susceptibility and false intermediate of 105 disc were higher than those of 105 disc.ConclusionsThe results of susceptibility test showed that 105 disc was more close to agar dilution than that of 150 disc.However,the 150 disc used in clinic led to increase in sensitivity of susceptibility test to organisms.

Objective:To understand the current status of anemia, iron deficiency, and iron-deficiency anemia among preschool children in China.Methods:A cross-sectional study was conducted with a multi-stage stratified sampling method to select 150 streets or townships from 10 Chinese provinces, autonomous regions, or municipalities (East: Jiangsu, Zhejiang, Shandong, and Hainan; Central: Henan; West: Chongqing, Shaanxi, Guizhou, and Xinjiang; Northeast: Liaoning). From May 2022 to April 2023, a total of 21 470 children, including community-based children aged 0.5 to<3.0 years receiving child health care and kindergarten-based children aged 3.0 to<7.0 years, were surveyed. They were divided into 3 age groups: infants (0.5 to<1.0 year), toddlers (1.0 to<3.0 years), and preschoolers (3.0 to<7.0 years). Basic information such as sex and date of birth of the children was collected, and peripheral blood samples were obtained for routine blood tests and serum ferritin measurement. The prevalence rates of anemia, iron deficiency, and iron-deficiency anemia were analyzed, and the prevalence rate differences were compared among different ages, sex, urban and rural areas, and regions using the chi-square test.Results:A total of 21 460 valid responses were collected, including 10 780 boys (50.2%). The number of infants, toddlers, and preschoolers were 2 645 (12.3%), 6 244 (29.1%), and 12 571 (58.6%), respectively. The hemoglobin level was (126.7±14.8) g/L, and the serum ferritin level was 32.3 (18.5, 50.1) μg/L. The overall rates of anemia, iron deficiency, and iron-deficiency anemia were 10.4% (2 230/21 460), 28.3% (6 070/21 460), and 3.9% (845/21 460), respectively. The prevalence rate of anemia was higher for boys than for girls (10.9% (1 173/10 780) vs. 9.9% (1 057/10 680), χ2=5.58, P=0.018), with statistically significant differences in the rates for infants, toddlers and preschoolers (18.0% (475/2 645), 10.6% (662/6 244), and 8.7% (1 093/12 571), respectively, χ2=201.81, P<0.01), and the rate was significantly higher for children in rural than that in urban area (11.8% (1 516/12 883) vs. 8.3% (714/8 577), χ2=65.54, P<0.01), with statistically significant differences in the rates by region ( χ2=126.60, P<0.01), with the highest rate of 15.8% (343/2 173) for children in Central region, and the lowest rate of 5.3% (108/2 053) in Northeastern region. The prevalence rates of iron deficiency were 33.8% (895/2 645), 32.2% (2 011/6 244), and 25.2% (3 164/12 571) in infants, toddlers, and preschoolers, respectively, and 30.0% (3 229/10 780) in boys vs. 26.6% (2 841/10 680) in girls, 21.7% (1 913/8 821), 40.0% (870/2 173), 27.1% (2 283/8 413), 48.9% (1 004/2 053) in Eastern, Central, Western, and Northeastern regions, respectively, and each between-group showed a significant statistical difference ( χ2=147.71, 29.73, 773.02, all P<0.01). The prevalence rate of iron-deficiency anemia showed a significant statistical difference between urban and rural areas, 2.9% (251/8 577) vs. 4.6% (594/12 883) ( χ2=38.62, P<0.01), while the difference in iron deficiency prevalence was not significant ( χ2=0.51, P=0.476). Conclusions:There has been a notable improvement in iron deficiency and iron-deficiency anemia among preschool children in China, but the situation remains concerning. Particular attention should be paid to the prevention and control of iron deficiency and iron-deficiency anemia, especially among infants and children in the Central, Western, and Northeastern regions of China.