[The first identification of epidemic clone of enterotoxic Escherichia coli O∶6 serogroup highly associated with azithromycin resistance in Shanghai]

Objective: To investigate the molecular characterization of adult diarrhea cases caused by enterotoxic Escherichia coli (ETEC) and explore the practical model of epidemiology for laboratory technique and data needs based on the surveillance network. Methods: Epidemiological design and sampling targeted adult cases ETEC caused diarrhea in epidemic season. The enterotoxin type, serogroup, resistance, colonization factor and molecular type of ETEC were identified. Multiple dynamic phenotypic characteristics of ETEC were indicated by multidimensional and multivariable data. Results: From 2016 to 2018, 84 eligible ETEC strains were detected. The dominant serums/toxins were O∶6 (STh), O∶25 (LT), O∶159 (STh), O∶153 (STh). O∶6 (STh+CS21), which replaced O∶25 and O∶159 as the popular clones in 2018. Six cases of O∶153 (STh+CFA/I+CS8+PT34) in outbreak in 2017 were imported ones. The resistance rates of ETEC strains detected in adults to sulfasoxazole, naproxinic acid, ampicillin and azithromycin were more than 30%, multidrug resistance (MDR) reached 58.3%. Serum/toxin types suggested that attenuated strains were more likely to become MDR. Molecular typing confirmed that the genetic similarity of the dominant clone of O∶6 serogroup (PT20-24) was higher than O∶25 and O∶159. There was a high correlation between the minimal inhibitory concentration (MIC) of azithromycin and the resistant gene mphA (87.5%, 28/32). O∶6 (STh+CS21+mphA) resistant clone was first detected in 2016. Conclusion: A new epidemic clone in adult ETEC diarrhea cases in Shanghai was O∶6 (STh+CS21+mphA). For the first time the association between azithromycin resistance gene mphA and a serum group of ETEC was observed. Multidimensional and multivariate analysis techniques based on epidemiology can help reveal the potential transmission pattern of ETEC for the accurate surveillance and early warning of outbreaks.

[An interlaboratory comparison study on the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels]

Objective: To investigate the current status and real performance of the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels in China through interlaboratory comparison. Methods: Peking University People's Hospital (PKUPH) prepared the samples for comparison. That is, the fresh RUNX1-RUNX1T1 positive (+) bone morrow nucleated cells were serially diluted with RUNX1-RUNX1T1 negative (-) nucleated cells from different patients. Totally 23 sets with 14 different samples per set were prepared. TRIzol reagent was added in each tube and thoroughly mixed with cells for homogenization. Each laboratory simultaneously tested RUNX1-RUNX1T1 and WT1 transcript levels of one set of samples by real-time quantitative PCR method. All transcript levels were reported as the percentage of RUNX1-RUNX1T1 or WT1 transcript copies/ABL copies. Spearman correlation coefficient between the reported transcript levels of each participated laboratory and those of PKUPH was calculated. Results: ①RUNX1-RUNX1T1 comparison: 9 samples were (+) and 5 were (-) , the false negative and positive rates of the 20 participated laboratories were 0 (0/180) and 5% (5/100) , respectively. The reported transcript levels of all 9 positive samples were different among laboratories. The median reported transcript levels of 9 positive samples were from 0.060% to 176.7%, which covered 3.5-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.5 to 12.3 (one result which obviously deviated from other laboratories' results was not included) , 85% (17/20) of the laboratories had correlation coefficient ≥0.98. ②WT1 comparison: The median reported transcript levels of all 14 samples were from 0.17% to 67.6%, which covered 2.6-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.3-13.7, 62% (13/21) of the laboratories had correlation coefficient ≥0.98. ③ The relative relationship of the reported RUNX1-RUNX1T1 transcript levels between the participants and PKUPH was not always consistent with that of WT1 transcript levels. Both RUNX1-RUNX1T1 and WT1 transcript levels from 2 and 7 laboratories were individually lower than and higher than those of PKUPH, whereas for the rest 11 laboratories, one transcript level was higher than and the other was lower than that of PKUPH. Conclusion: The reported RUNX1-RUNX1T1 and WT1 transcript levels were different among laboratories for the same sample. Most of the participated laboratories reported highly consistent result with that of PKUPH. The relationship between laboratories of the different transcript levels may not be the same.

Equivalence of Assurance® Gold Enzyme Immunoassay for Visual or Instrumental Detection of Motile and Nonmotile Salmonella in All Foods to AOAC Culture Method: Collaborative Study

Six foods representative of a wide variety of processed, dried powder processed, and raw food types were analyzed by the Assurance® Gold Salmonella Enzyme Immunoassay (EIA) and AOAC INTERNATIONAL culture method. Paired samples of each food type were simultaneously analyzed; one sample by the Assurance method and one by the AOAC culture method. The results for Assurance method were read visually and instrumentally with a microplate reader. A total of 24 laboratories representing federal government agencies and private industry, in the United States and Canada, participated in this collaborative study. Food types were inoculated with species of Salmonella with the exception of raw ground chicken, which was naturally contaminated. No statistical differences (p < 0.05) were observed between Assurance Gold Salmonella EIA with either visual or instrumental interpretation and the AOAC culture method for any inoculation level of any food type or naturally contaminated food. The Assurance visual and instrumental options of reading sample reactions produced the same results for 1277 of the 1296 sample and controls analyzed.

First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA

The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{μ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{μ}→ν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{μ}→ν[over ¯]_{μ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3}  eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ.

[Epidemiological characteristics and antibiotic resistance of Campylobacter spp. among diarrhea outpatients in Shanghai, 2013-2016]

Objective: To understand the epidemiological characteristics and antibiotic resistance profiles of Campylobacter spp. in Shanghai from 2013 to 2016. Methods: Stool samples collected from diarrhea outpatients were cultured for Campylobacter spp., using the membrane filter method in 23 hospitals under the sentinel programs, from 2013 to 2016. All the strains were identified by biochemical tests and PCR. Broth microdilution method was used to investigate the antibiotic resistance of 179 Campylobacter spp. strains that including azithromycin, ciprofloxacin, erythromycin, gentamicin, tetracycline, nalidixic acid, telycin, klinthromycin and flurbenicol. Results: A total of 179 Campylobacter spp. strains were isolated from 10 444 stool samples (1.7%). Campylobacter jejuni and Campylobacter coli appeared as the predominant ones (94.4% and 5.6%). The incidence rate was higher in children than that in adults, with peaks of infections mainly from April to June and October to December. Campylobacter jejuni strains seemed highly resistant to ciprofloxacin (96.4%), tetracycline (83.4%) and nalidixic acid (81.7%). The resistant rates appeared higher on Campylobacter coli strains that isolated from patients. Some strains were resistant to multi-drugs. Conclusions: Campylobacter spp. seemed one of the important pathogens that isolated from outpatients with diarrhea, in Shanghai. Both age and season related characteristics of Campylobacter spp. were seen. Campylobacter spp. isolated from patients was highly resistant to ciprofloxacin, tetracycline and nalidixic acid.

Extraction of the ^{235}U and ^{239}Pu Antineutrino Spectra at Daya Bay

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

Validating the Reliable Change Index with Tensor-Based Morphometry: the ADNI-MEM and the ADNI-EF

Objective

The Reliable Change Index (RCI) is a commonly used method for interpreting change in neuropsychological test scores over time. However, the RCI is a psychometric phenomenon that, to date, has not been validated by neuroanatomical evidence.

Method

Longitudinal neuroimaging and neuropsychological data from baseline and one-year follow-up visits were retrieved from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database. The RCI was used to identify participants showing reliable decline on ADNI-MEM and ADNI-EF factor scores, which provide composite measures of memory and executive functioning, respectively. For each cognitive test score, two groups (reliable change vs. no reliable change) were matched on potential confounding variables using a genetic algorithm. Longitudinal neuroanatomical data were analyzed using tensor-based morphometry.

Results

Whole brain analysis revealed that reliable change on ADNI-MEM was associated with extended atrophy of the temporal lobe, the parahippocampal gyrus, the entorhinal cortex, and the posterior cingulate gyrus (Left Figure). Similar extended atrophy patterns were found for reliable change on ADNI-EF, except that the atrophy was more extensive and of higher magnitude (Right Figure). Regional analysis further confirmed that in such brain regions, the reliable change group manifested higher grey matter loss than the no change group.

Conclusion

The current study not only validated clinical usage of the RCI with neuroanatomical evidence but also practically suggested patterns of likely brain atrophy when reliable cognitive decline is detected.

[Seasonality and etiological characteristics of infectious diarrhea in outpatients of 18 or above-year-old in Shanghai, 2014-2017]

Objective: To understand the seasonality and etiological characteristics of infectious diarrhea in adults from Shanghai. Methods: Adult patients with diarrhea who had visited the enteric disease clinics in 22 hospitals that carrying on the Diarrhea Comprehensive Surveillance sentinel programs in Shanghai during 2014-2017, were surveyed. Stool specimens were collected according to the different intervals of sampling and detected for 12 bacteria and 5 viruses. Concentration ratio and circular distribution method were used for data analysis. Results: From 2014 to 2017, a total of 9 573 stool specimens were collected from the targeted diarrhea patients ≥18 years old (n=96 067), through the Shanghai Diarrhea Comprehensive Surveillance program. The positive rate of detection was 46.44%. Seasonal peaks of infectious diarrhea were both seen in summer (bacteria peak, diarrheagenic Escherichia coli and Vibrio parahaemolyticus, etc.) and in winter (virus peak, Norovirus, etc.). Both bacterial and viral infections presented seasonal concentration (Raleigh's test P<0.001) but more obvious with bacterial infection. Viral infection accounted for 60.19% of the cause of infectious diarrhea. The top five predominant pathogens appeared as Norovirus, Rotavirus, diarrheagenic Escherichia coli, Vibrio parahaemolyticus, and Salmonella spp.. Conclusions: Among the adult outpatients with infectious diarrhea in Shanghai, obvious seasonality was seen, with peaks in both summer and winter. Viral infection with Norovirus in particular, appeared as the predominant source of infection. Active, continuous and comprehensive diarrhea-related surveillance programs would be able to monitor the changing dynamic of pathogen spectrum, and lead to the adoption of targeted preventive measures.

[Epidemiologic characteristics of Norovirus among adult patients with infectious diarrhea, in Shanghai, 2013-2018]

Objective: To investigate the epidemiologic characteristics of Norovirus among adult patients suffering from infectious diarrhea in Shanghai, so as to provide evidence for developing related strategies on prevention and control of the disease. Methods: Diarrheal outpatients were monitored at the 'Intestinal clinic' from 22 hospitals involved in the sentinel surveillance program in Shanghai. Information on demographic and epidemiologic features of the patients was collected while data and clinical, fecal specimens were collected and sent to the district CDC for Norovirus detection. Positive rates of Norovirus were also compared in various populations and seasons during 2013-2018. Multivariate logistic regression model was adopted to fit into the comparisons between non-Norovirus and Norovirus groups. Results: 19.28% of the 12 083 diarrheal cases were found to have carried the Norovirus, with GⅡgroup the most commonly identified genotype. Rates of detection was seen higher in males (20.78%) than in females (17.73%). 30-44 year-old were found having the highest positive rate (21.51%). The positive rates were found the highest (23.60%) in the year of 2015. All the above shown differences were statistically significant (P<0.05). Diarrheal patients affected with Norovirus would present watery stool (75.94%) and vomiting (35.84%). Data from the multivariate logistic analysis showed that factors as: being males, 30-44 years old, officials/clerks, in winter season and with histories of travelling etc., were related to higher risks on Norovirus infection. Conclusions: Infectious diarrhea caused by Norovirus occurred all year round, with seasonal peaks seen in winter and spring, in Shanghai. Specific prevention and control measures should be taken on Norovirus- caused infectious diarrhea, according to the difference on age, gender and season.