Neuromyelitis optica (NMO) is an inflammatory-demyelinating disease of central nervous system that is characterized by severe attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM).Conventional MRI is the most sensitive method in detection of NMO lesions in brain,spinal cord and optic nerve,which can objectively show the site,number,size and distribution of lesions.The MRI features of NMO lesion in brain,spinal cord and optic nerve lesions were reviewed in this article.

Objective: To evaluate the dietary quality by adjusted diet balance index (DBI_16) of preschool left behind children in Anhui Province, and to provide a reference for rapidly and accurately evaluating their nutrition condition. Methods: During September to December of 2018, selected 306 left behind children and 598 non left behind children aged 3-6 years old of Anhui Province in total. Four scoring methods (TS total score, LBS Low Bound Score, HBS High Bound Score, DQD Diet Quality Distance) were used to evaluate the dietary quality by Diet Balance Index Revision (DBI_16), and scores were compared to reflect the diet quality of preschool children in LBC group and NLBC group. Results: The score of TS (-18.2, -16.1) in LBC group was lower than that of NLBC group, the scores of LBS(24.8, 23.1), HBS (7.9, 6.4) and DQD (35.9, 34.4) in LBC group were higher than that of NLBC group( Z =-46.02, 12.45, 4.14, 4.78, P <0.05). The daily intake of vegetables, fruits, animal food, milk, soybean and drinking water were obviously under the RNI, the dietary intake scores of milk(-4.1, -2.7), animal food (-2.2, -0.8) and food species (-7.4, -6.2) in LBC group were higher than that in NLBC group( Z =-26.42, 13.51, -6.59, P <0.01). About 44.1% of the preschool LBC were in moderate or severe deficit of food intake, 66.0% of the LBC were in the higher level of dietary imbalance, the LBC group s excessive and imbalance problem were of significant differences than those in the NLBC group ( χ 2=15.79, 11.51, P <0.05). Conclusion The dietary quality of preschool children in Anhui Province should be improved, the main diet problem was the dietary imbalance, which was related to deficiency in nutrients intake. The scores of DBI_16 in LBC group were significant different with those in NLBC group, it is necessary to take specific intervention to increase the intake of milk, eggs and fruits among preschool children.

Objective To establish a molecular typing system of Staphylococcus aureus by using resolution melting for food-poi-soning fast tracing.Methods Primers were designed and synthesized according to the literature of VNTR in Staphylococcus au-reus ,and were used to perform molecular typing on the strains which had detected by PFGE,then 4 types of VNTRs were with higher discriminatory power were selected.On this basis,we established a molecular typing system for the detection of 59 Staphy-lococcus aureus isolated from food poisoning.Results The molecular typing system has good precision for detection.The standard deviation(s)of within-batch repetitive experiments were 0.03 -0.05 ℃,between-batch repetitive experiments were 0.04 -0.06℃,between-day repetitive experiments were 0.04-0.06 ℃.At the same time,the 59 strains of Staphylococcus aureus were divided into 19 types which were 11 epidemic clones and 8 sporadic clones.The correlation coefficient of Simpson was 0.916 4.Conclusion The molecular typing system for Staphylococcus aureus based on resolution melting was simple,fast and repeatable.It can be ap-plied to fast tracing and screen of Staphylococcus aureus in food poisoning.

Objective: To evaluate the dietary quality for preschool children by diet balance index(DBI_C), and to provide an empirical reference for scientific guidance for a reasonable diet and controlling and preventing iron deficiency anemia(IDA). Methods: During September to December of 2018, 306 left behind children and 598 non left behind children aged 3-6 years old of Anhui Province were selected. Four scoring methods (TS Total Score, LBS Low Bound Score, HBS High Bound Score, DQD Diet Quality Distance) were used to evaluate the dietary quality by DBI_C, and multivariate Logistic regression was used to assess the relationship between DBI_C and IDA. Results: The anemia prevalence (AP) was 13.3% among the 3-6 year old children in Anhui rural area, whereas the left behind children (LBC) was 16.7% and the non left behind children was 10.9%, and there was statistical significance of the differences ( χ 2=8.8, P <0.05). There were significant differences of TS[-18.3(25.2，-12.7)，-15.2(-19.8，-8.6)], LBS[25.4(18.3，32.5)，22.7(16.5，30.6)] and DQD[36.8(23.9，43.4)，34.1(27.5，41.0)] in DBI_C scores between anemia group and nonanemia group ( P <0.05). There were significant differences of milk and beans [-5.9(-10.7，-0.4)，-5.0(-8.7，0.2)], animal food [-2.4(-5.6，0.8)，-0.6(3.5，1.9)], food species [-7.5(-9.1，-4.8)，-6.3(-8.0，-2.9)] in food intake scores between anemia group and non anemia group ( P <0.05). Left behind children ( OR =1.27, 95% CI =1.15-1.49) had higher proportions of getting anemia. Meat consumption >3 times per week ( OR =0.81, 95% CI =0.68-0.94) and ≥two types of fresh vegetable consumption every day ( OR =0.84, 95% CI =0.73-0.95) were associated with lower rate of anemia( P <0.05). Conclusion The AP was relatively high in 3-6 year old children in Anhui rural area, especially in those LBC. Anemia should be reduced by improving the caregivers dietary literacy, increasing intakes of animal foods and fresh vegetables.

Objective To explore the role of CD44 in monocyte adhesion to human brain microvascular endothelial cells (HBMECs) and monocyte migration across an in vitro model of blood-brain barrier (BBB) infected by Cryptococcus neoformans (Cn). Methods An in vitro blood-brain barrier model was constructed using a transwell chamber covered with a HBMEC monolayer. The wild-type strain of Cn B4500FO2, TYCC645#32 strain with CPS1 gene deletion and PCIP strain with CPS1 complementation were chosen to infect the monolayer HBMECs. THP-1 cells were added to the upper chamber of transwell, and the relative migration rate was determined by counting the number of the cells entering the lower chambers. The inhibitory effects of anti-CD44 monoclonal antibody and the CD44 inhibitor bikunin were examined on THP-1 binding to and migration across HBMECs. Results Cn infection of the HBMECs caused markedly enhanced THP-1 cell adhesion and migration across the monolyers (P<0.01) dependent on Cn concentration and exposure time. Addition of anti- CD44 monoclonal antibody and bikunin significantly lowered THP-1 adhesion and migration rates in the BBB model with Cn-infected HBMECs (P<0.01) with a dose dependence of the antibody (within 0-1μg) and inhibitor (within 0-20 nmol/L). Both THP-1 adhesion rate and migration rate were lowered in the BBB model infected with CPS1 gene-deleted Cn but increased in the model infected with the complemented strain compared with those in the wild-type strain-infected model. Conclusion In the in vitro BBB model, CD44 expressed on HBMECs may play an essential role in monocyte adhesion to and migration across the BBB. The capsular hyaluronic acid may mediate Cn-induced monocyte adhesion and migration.

Objective To explore the role of CD44 in monocyte adhesion to human brain microvascular endothelial cells (HBMECs) and monocyte migration across an in vitro model of blood-brain barrier (BBB) infected by Cryptococcus neoformans (Cn). Methods An in vitro blood-brain barrier model was constructed using a transwell chamber covered with a HBMEC monolayer. The wild-type strain of Cn B4500FO2, TYCC645#32 strain with CPS1 gene deletion and PCIP strain with CPS1 complementation were chosen to infect the monolayer HBMECs. THP-1 cells were added to the upper chamber of transwell, and the relative migration rate was determined by counting the number of the cells entering the lower chambers. The inhibitory effects of anti-CD44 monoclonal antibody and the CD44 inhibitor bikunin were examined on THP-1 binding to and migration across HBMECs. Results Cn infection of the HBMECs caused markedly enhanced THP-1 cell adhesion and migration across the monolyers (P<0.01) dependent on Cn concentration and exposure time. Addition of anti- CD44 monoclonal antibody and bikunin significantly lowered THP-1 adhesion and migration rates in the BBB model with Cn-infected HBMECs (P<0.01) with a dose dependence of the antibody (within 0-1μg) and inhibitor (within 0-20 nmol/L). Both THP-1 adhesion rate and migration rate were lowered in the BBB model infected with CPS1 gene-deleted Cn but increased in the model infected with the complemented strain compared with those in the wild-type strain-infected model. Conclusion In the in vitro BBB model, CD44 expressed on HBMECs may play an essential role in monocyte adhesion to and migration across the BBB. The capsular hyaluronic acid may mediate Cn-induced monocyte adhesion and migration.

Objective To analyze the etiological characteristics,virulence genes and plasmids that carrying diarrhea-causing Proteus mirabilis and to assess their relationship with drug resistance and pathogenicity. Methods Proteus mirabilis coming from six different sources (food poisoning,external environment and healthy people) were analyzed biochemically,on related susceptibility and pulsed-field gel electrophoresis (PFGE). Virulence genes were detected by PCR. Plasmids were extracted and sequenced after gel electrophoresis purification. Results The biochemical characteristics of Proteus mirabilis from different sources seemed basically the same,and each of them showed having common virulence genes,as ureC,rsmA,hpmA and zapA. However,the PFGE patterns and susceptibility of these strains were different,so as the plasmids that they carried. Plasmid that presented in the sequenced strain showed that the 2 683 bp length plasmid encodes qnrD gene was associated with the quinolone resistance. Conclusion Etiological characteristics and molecular characteristics of Proteus mirabilis gathered from different sources,were analyzed. Results indicated that traditional biochemical analysis and common virulence gene identification might be able to distinguish the strains with different sources. However,PFGE and plasmids analysis could distinguish the sources of strains and to identify those plasmids that commonly carried by the drug-resistant strains. These findings also provided theoretical basis for further study on the nature of resistance and pathogenicity in Proteus mirabilis.

OBJECTIVETo understand the epidemiologic and etiologic characteristics of diarrheagenic Escherichia (E.) coli infections in Shenzhen.

METHODSStool samples were collected from acute diarrheal patients in four sentinel hospitals in Shenzhen and diarrheagenic E. coli strains were isolated and identified with multiplex real-time PCR. Serotyping and pulsed-field gel electrophoresis (PFGE) typing were conducted for the diarrheagenic E. coli isolates.

RESULTSA total of 74 diarrheagenic E. coli strains were isolated from 1 823 stool samples (4.06%). The patients were mainly young children aged <3 years and adults aged 20-39 years, and the infections mainly occurred during May-September of a year. Enterotoxigenic E. coli (ETEC) and enteropathognic E. coli (EPEC) were predominant (45.9% and 31.1%). Serogroups and PFGE patterns varied among the diarrheagenic E. coli isolates. However, serogroup O159 were predominant in ETEC and there were 5 clusters with ≥2 strains sharing same PFGE patterns.

CONCLUSIONSETEC and EPEC were predominant in diarrheagenic E. coli strains isolated from diarrheal patients in Shenzhen. Age and season specific characteristics of diarrheagenic E. coli infections were observed. The serotypes and PFGE patterns of diarrheagenic E. coli strains varied. Close attention should be paid to the possible ETEC outbreak.

Adult ; Child, Preschool ; China ; epidemiology ; Diarrhea ; epidemiology ; microbiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; Enterotoxigenic Escherichia coli ; classification ; isolation & purification ; Escherichia coli Infections ; epidemiology ; Humans ; Real-Time Polymerase Chain Reaction ; Serotyping ; Young Adult

OBJECTIVETo analyze the etiological characteristics, virulence genes and plasmids that carrying diarrhea-causing Proteus mirabilis and to assess their relationship with drug resistance and pathogenicity.

METHODSProteus mirabilis coming from six different sources (food poisoning, external environment and healthy people) were analyzed biochemically, on related susceptibility and pulsed-field gel electrophoresis (PFGE). Virulence genes were detected by PCR. Plasmids were extracted and sequenced after gel electrophoresis purification.

RESULTSThe biochemical characteristics of Proteus mirabilis from different sources seemed basically the same, and each of them showed having common virulence genes, as ureC, rsmA, hpmA and zapA. However, the PFGE patterns and susceptibility of these strains were different, so as the plasmids that they carried. Plasmid that presented in the sequenced strain showed that the 2 683 bp length plasmid encodes qnrD gene was associated with the quinolone resistance.

CONCLUSIONEtiological characteristics and molecular characteristics of Proteus mirabilis gathered from different sources, were analyzed. Results indicated that traditional biochemical analysis and common virulence gene identification might be able to distinguish the strains with different sources. However, PFGE and plasmids analysis could distinguish the sources of strains and to identify those plasmids that commonly carried by the drug-resistant strains. These findings also provided theoretical basis for further study on the nature of resistance and pathogenicity in Proteus mirabilis.

Diarrhea ; microbiology ; Drug Resistance, Bacterial ; Genes, Bacterial ; Humans ; Plasmids ; genetics ; Proteus mirabilis ; genetics ; pathogenicity ; Virulence Factors ; genetics