ObjectiveTo monitor the real-time changes in ammonia concentration in the laboratory animal facility environment before, during, and after the air conditioning system stops supplying air, so as to provide a basis and reference for developing emergency plans for the shutdown of the air conditioning system. MethodsThe laboratory animal facilities of the Wuhan Institute of Biological Products were used as the research object. Ammonia concentration detectors were used to monitor ammonia concentration continuously in the environment of conventional rabbit production facility, SPF hamster production facility, and SPF guinea pig experimental facility before and after the passive shutdown due to repairs and active maintenance shutdown of the air conditioning system, as well as the time for the ammonia concentration to return to daily levels after resuming air supply. ResultsUnder both shutdown modes of the air conditioning system, the trend of ammonia concentration changes in different laboratory animal facilities was consistent, showing a rapid increase after shutdown and a rapid decrease after resuming air supply. Under active maintenance shutdown, the maximum ammonia concentrations in the conventional rabbit production facilities, SPF hamster production facilities, and SPF guinea pig experimental facilities were 9.81 mg/m³, 14.27 mg/m³, and 6.98 mg/m³, respectively. Within 12 minutes after resuming air supply, ammonia concentration could return to normal daily levels. Under passive long-term shutdown, ammonia concentration value was positively correlated with the duration of air supply suspension. As the shutdown duration increased, ammonia concentration continued to increase. The maximum ammonia concentration values in the three facilities occurred at 88 minutes (38.06 mg/m³), 40 minutes (18.43 mg/m³), and 34 minutes (15.61 mg/m³) after air supply suspension, respectively.Within 11 minutes after resuming air supply, ammonia concentration could return to normal daily levels. ConclusionShutdown of the air conditioning system causes a rapid increase in ammonia concentration in laboratory animal facilities, and the rise in ammonia concentration is positively correlated with the duration of air supply suspension. Therefore, when an emergency shutdown of the air-conditioning system is required due to maintenance or other reasons, backup fans should be provided in accordance with the requirements of GB 50447-2008 "Architectural and Technical Code for Laboratory Animal Facilities". Older facilities should make adequate preparations and develop a scientifically sound emergency plan.

Humans ; Diagnosis, Differential ; Constriction, Pathologic/diagnosis* ; Bile Duct Neoplasms/diagnosis* ; Endoscopy, Digestive System

Objective:To explore the therapeutic effect of peroral endoscopic myotomy (POEM) for primary achalasia (AC) in patients aged over 60 years.Methods:Data of 146 patients aged ≥60 years (the elderly group) and 146 patients aged 18-59 years (the adult group) who received POEM from November 2010 to September 2019 at the Digestive Endoscopy Center of PLA General Hospital were retrospectively analyzed. Baseline data, surgery data, surgery-related complications and surgery-related efficacy were compared.Results:There was no significant difference in gender, Ling classification, HRM classification or previous treatment between the two groups ( P>0.05). All 292 patients successfully underwent POEM surgery. The clinical success (Eckardt score ≤3) rates in the elderly group and the adult group were 96.33% (105/109) and 96.77% (90/93), respectively with no significant difference between the two groups ( χ2=0.030， P>0.05). There was no significant difference in the length of myotomy between the two groups (7.09±2.49 cm VS 7.12±2.24 cm， t=0.472， P>0.05). Complications occurred in 26 cases (17.81%) in the elderly group and 21 cases (14.38%) in the adult group with no significant difference between the two groups ( χ2=0.634， P>0.05). There was no significant difference in the postoperative hospital stay (12.61±9.69 days VS 11.00±4.43 days, t=1.825, P>0.05) or the incidence of gastroesophageal reflux [43.33% (13/30) VS 51.52% (17/33), χ2=0.422, P>0.05] between the elderly group and the adult group. Conclusion:The efficacy of POEM for AC patients over 60 years old is equivalent to that of adult patients, and the incidence of complications is similar. POEM is safe and effective for AC patients over 60 years old.

Objective: Comparative analyses of wild-type Clostridioides difficile 630 (Cd630) strain and pathogenicity locus (PaLoc) knockout mutant (ΔPaLoc) by using RNA-seq technology. Analysis of differential expression of Cd630 wild-type strain and ΔPaLoc mutant strain and measurement of its cellular virulence changes. Lay the foundation for the construction of an toxin-attenuated vaccine strain against Clostridioides difficile. Methods: Analysis of Cd630 and ΔPaLoc mutant strains using high-throughput sequencing (RNA-seq). Clustering differentially expressed genes and screening differentially expressed genes by DESeq software. Further analysis of differential genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Finally, cytotoxicity assays of ΔPaLoc and Cd630 strains were performed in the African monkey kidney epithelial cell (Vero) and the human colonic cell (Caco-2) lines. Results: The transcriptome data showed that the ΔPaLoc mutant toxin genes tcdA and tcdB were not transcribed. Compared to the wild-type strain, CD630_36010, CD630_020910,CD630_02080 and cel genes upregulated 17.92,11.40,8.93 and 7.55 fold, respectively. Whereas the hom2 (high serine dehydrogenase), the CD630_15810 (spore-forming protein), CD630_23230 (zinc-binding dehydrogenase) and CD630_23240 (galactitol 1-phosphate 5-dehydrogenase) genes were down-regulated by 0.06, 0.075, 0.133 and 0.183 fold, respectively. The GO and KEGG enrichment analyses showed that the differentially transcribed genes in ΔPaLoc were enriched in the density-sensing system, ABC transport system, two-component system, phosphotransferase (PTS) system, and sugar metabolism pathway, as well as vancomycin resistance-related pathways. Cytotoxicity assays showed that the ΔPaLoc mutant strain lost its virulence to Vero and Caco-2 cells compared to the wild-type Cd630 strain. Conclusion: Transcriptional sequencing analysis of the Cd630 and ΔPaLoc mutant strains showed that the toxin genes were not transcribed. Those other differential genes could provide a reference for further studies on the physiological and biochemical properties of the ΔPaLoc mutant strain. Cytotoxicity assays confirmed that the ΔPaLoc mutant lost virulence to Vero and Caco-2 cells, thus laying the foundation for constructing an toxin-attenuated vaccine strain against C. difficile.
Bacterial Proteins/metabolism* ; Bacterial Toxins/metabolism* ; Caco-2 Cells ; Clostridioides ; Clostridioides difficile/genetics* ; Humans ; Oxidoreductases/metabolism* ; Transcriptome ; Vaccines, Attenuated

Objective To understand the iodine nutritional status and thyroid function of different populations after 20 years of universal salt iodization in iodine deficiency area of Shanxi Province, and to provide data support for scientific iodine supplementation according to local conditions. Methods In 2014, six townships (Chengguan, Dadeng, Dengzhuang, Gucheng, Xiangling and Fencheng townships) in Xiangfen County, Linfen City, Shanxi Province, were selected as the place of investigation. Four hundred school-age children aged 6 - 12 years (school-age children), 400 child-bearing women aged 18 - 44 (child-bearing women), 400 pregnant women, 400 lactating women and their 0 - 6 months breast-feeding infants (breast-feeding infants), and 400 children aged 7 -24 months were selected by two-stage sampling method. Water samples of school-age children's domestic drinking water and salt samples for domestic consumption were collected, and the water iodine and salt iodine were detected by arsenic and cerium catalytic spectrophotometry ( recommended by the National Iodine Deficiency Disorders Reference Laboratory) and "General Test Method in Salt Industry-Determination of Iodine" (GB/T 13025.7-2012). Random urine samples of all subjects were collected, urine iodine was detected by "Method for Determination of Iodine in Urine by As3+-Ce4+ Catalytic Spectrophotometry" ( WS/T 107-2006 ) . Samples of filter paper dried blood spots (DBS) of school-age children, child-bearing women, pregnant women, lactating women and breast-feeding infants were collected, and serum total thyroxine (TT4) and thyroid stimulating hormone (TSH) levels were detected by time-resolved fluorescence immunoassay. Results A total of 290 water samples were collected, and the median of water iodine was 9.37μg/L. A total of 406 salt samples were collected, the median of salt iodine was 25.0 mg/kg, the coverage rate of iodized salt was 98.52％ (400/406), and the consumption rate of qualified iodized salt was 92.61％ (376/406). Urine samples of 389 school-age children, 379 child-bearing women, 363 pregnant women, 365 lactating women, 366 breast-feeding infants, and 366 children aged 7 - 24 months were collected, and the medians of urine iodine were 200.7, 175.0, 186.0, 113.2, 285.8 and 204.8 μg/L, respectively. Among them, school-age children, breast-feeding infants, and children aged 7-24 months were over the appropriate level, while the rest populations were at the iodine appropriate levels. Blood samples of 402 school-age children, 397 child-bearing women, 398 pregnant women, 390 lactating women, and 386 breast-feeding infants were collected, and the medians of TT4 were 127.2, 110.2, 141.7, 95.8 and 139.0 nmol/L, respectively; the medians of TSH were 1.2, 0.9, 0.8, 0.9 and 0.9 mU/L, respectively, and they were all within the reference ranges. The abnormal rates of TT4 (8.46％, 33/390) and TSH (7.95％, 31/390) in lactating women were higher than those in school-age children, child-bearing women, pregnant women and breast-feeding infants [TT4 abnormal rates were 0.25％(1/402), 1.26％ (5/397), 0.50％ (2/398), 1.04％ (4/386), respectively; TSH abnormal rates were 1.24％ (5/402), 1.51％ (6/397), 1.51％ (6/398) and 0.78％ (3/386), respectively, P < 0.05]. The rate of thyroid dysfunction in lactating women (7.95％, 31/390) was higher than those in the rest populations [1.24％ (5/402), 1.51％ (6/397), 1.51％ (6/398), 0.78％ (3/386), P < 0.05]. Conclusions The iodine intake of different populations in the survey area is generally sufficient, and the current salt iodine content standard can meet the iodine nutrition needs of different populations. Lactating women have a high rate of thyroid dysfunction. It is suggested to stick to the strategy of universal salt iodization to prevent iodine deficiency hazards in iodine deficiency areas, and further strengthen the monitoring of iodine nutrition and thyroid function of pregnant women and lactating women.

Objective To evaluate the effects of prevention and control measures on coal-burning-borne endemic fluorosis in Shanxi Province, and to provide a scientific basis for further prevention and treatment of the disease. Methods In 2016, 7 diseased counties (cities) were selected in the whole province, three diseased townships were selected in each county(city), and five diseased villages were selected in each diseased township as the investigation sites. The investigation was carried out on the changes of improved stove and correct usage of the improved stove, and the correct drying behavior related to the corn and pepper for human consumption. Children aged 8 to 12 were examined dental fluorosis. In each village, 20 urine samples of 8 to 12 years old children were collected for fluorine determination. Urine fluoride was determined via the fluoride ion selective electrode method, and children dental fluorosis was diagnosed by "Diagnosis of Dental Fluorosis" method (WS/T 208-2011). Results Altogether 105 villages were investigated, including 31 696 households. The rates of the improved stove and the correct usage of the improved stove were 98.46%(31 209/31 696)and 98.80%(30 834/31 209);the correct drying rate related to the corn and pepper for human consumption was 99.97%(31 685/31 696);the dental fluorosis rate of 8 to 12 years old children,and the dental fluorosis index were 5.56%(264/4 751) and 0.13. The urine fluoride content was between 0.15 - 4.33 mg/L and the geometric mean value of fluoride content was 0.72 mg/L. Conclusions The prevention and control effect is obvious on coal-burning-borne endemic fluorosis in Shanxi Province. Disease surveillance,health education,the management and maintenance work of defluoridation stoves are keys in prevention of coal-burning-borne endemic fluorosis.

Objective To evaluate the effect of water improvement projects on drinking-water-borne endemic arsenism in Shanxi Province,to work out and refine sustainable prevention and control strategies.Methods The operating situation of water-improvement projects was investigated and monitored,and the arsenic content in drinking water was determined in drinking-water-borne arseniasis areas,which including 14 monitored sites in 5 countries from 2012 to 2017.The condition of arsenic poisoning in the resident population of the monitored sites was investigated and the arsenic content in the urine of patients was determined.Results Totally 14 monitored sites were already finished water improvement,the rate of water-improvement was 100％.Totally 11 water-improvement projects were monitored,including 7 small-scale water-improvement projects and 4 large-scale water-improvement projects,which all qualified and operated normally from 2012 to 2015.In 2016,one water-improvement project was found with excessive level (＞ 0.01 mg/L) of arsenic in drinking water in Shanyin County,and the other 10 water-improvement projects' arsenic contents were qualified.In 2017,two unqualified large-scale water-improvement projects had water arsenic content over (＞ 0.01 mg/L) in Shanyin County and Ying County,respectively.And the other 9 water-improvement projects were qualified.The detection rates of arsenic poisoning from 2012 to 2017 were 1.36％ (104/7 641),1.57％ (123/7 832),1.61％ (123/7 621),1.53％ (120/7 857),1.28％ (102/7 963) and 1.56％ (124/7 958),respectively,and the differences were not statistically significant (x2 =4.979 9,P ＞0.05).Most patients with arsenic poisoning were mild to moderate patients,accounted for 82.61％ (575/696) and no new case was detected.Conclusions Arsenic poisoning in drinking-water-borne arseniasis areas in Shanxi Province has been controlled.Natural operation of water-improvement projects has kept water arsenic levels normal.Water arsenic content has exceeded the standard in some of the water-improvement projects.The key point of next stage is strengthen the management of water improvement projects in prevention and treatment of drinking-water type endemic arsenism.

Objective: To analyze the incidence and microbiological features of blood stream infections (BSI) of patients with hematopoietic stem cell transplantation (HSCT) and to provide laboratory data for empirical use of antibiotic for the HSCT patients with BSI. Methods: The incidence of bloodstream infection, the positive rate of blood culture, bacterial spectrum and drug resistance were analyzed in 1 265 HSCT recipients during 2013 and 2015 were retrospectively studied. Results: Of 1265 patients undergoing HSCT, 1 422 cases of suspected BSI occurred in 784 patients (61.98%) , and 464 patients (59.2%) were in the stage of agranulocytosis (ANC<0.5×10⁹/L) . The detection rate of pathogens in 2013-2015 was about 20% and increase year after year. Of the 401 strains detected, 221 were Gram-negative (G^-) bacteria (55.1%) , 165 Gram-positive (G⁺) bacteria (41.2%) and 15 fungi (3.7%) . Escherichia coli (16.0%) , Staphylococcus epidermidis (15.5%) and Klebsiella pneumoniae (11.2%) were listed the top three. The proportion of multidrug resistant Acinetobacter Bauman and Stenotrophomonas maltophilia was 64.70% and 63.64% respectively, and methicillin resistant Staphylococcus aureus (MRSA) was more than half (57.14%) . The ratio of vancomycin resistant Enterococci (VRE) and carbapenem resistant Enterobacteriaceae (CRE) was 14.29% and 6.78% respectively. More than 40% Enterobacteriaceae bacteria were resistant to three or four generation cephalosporin antibiotics, and less were resistant to the carbapenems (6.4%) . However, many non-fermentating bacteria were highly resistant to these antibiotics and showed diversity among different strains, with a rate of 47.8% resistance to carbapenems. All the Staphylococcus were sensitive to vancomycin, teicoplanin and linezolid. Conclusions The incidence of BSI in patients with HSCT was high, and the pathogens were mainly G^- bacteria. In addition to Enterobacteriaceae, the proportion of non-fermentative bacteria was quite high. No Staphylococcus detected were resistant to vancomycin, teicoplanin and linezolid.

Objective To master the iodine nutritional status of residents and to evaluate the effect of iodine nutrition improvement on residents health after the adjustment of salt iodine concentration. Methods According to the method of population proportion sampling, 30 county-level monitoring sites were selected in 2014, a primary school was selected from each county (city, district) by the method of simple random sampling and 50 students aged 8 - 10 (half males and half females) were selected in each school, B ultrasound was used to detect thyroid volume, arsenic cerium catalytic spectrophotometry (WS/T 107-2006) was used to detect urinary iodine, direct titration was used to detect salt iodine; At the same time, 20 pregnant women were selected from each town and urinary iodine was determined. All results were compared with the results of 2011 to evaluate the effect of iodine nutrition improvement on resident's health after the adjustment of salt iodine concentration. Results A total of 1 437 edible salt samples were tested, the median of salt iodine concentration was 24.1 mg/kg. Based on the new standard (18 - 33 mg/kg), the coverage rate of iodized salt was 95.4%(1 371/1 437), the qualified rate of iodized salt was 80.3%(1 101/1 371), the consumption rate of qualified iodized salt was 76.6% (1 101/1 437). A total of 1 496 urine samples of children and 630 urine samples of pregnant women were tested, the median of urinary iodine of children and pregnant women was 224.6 and 177.1 μg/L, respectively, which were significantly lower than those of 2011 (274.6, 279.6μg/L), the differences were statistically significant (H=70.10, 153.50, all P<0.05). The proportion of counties which iodine nutrition of children and pregnant women in suitable range was 36.7% (11/30) and 56.7% (17/30), which were higher than those of 2011 [6.5%(2/31), 25.8%(8/31)], the differences were statistically significant (χ2 = 7.88, 5.00, all P < 0.05). Totally 1 552 children were examined thyroid in Shanxi Province, the rate of goiter was 4.4% (69/1 552). Conclusion The new standard of iodine concentration makes it possible to maintain a sustainable elimination of iodine deficiency disorders, and it can improve the iodine nutrition of children aged 8-10 years and pregnant women to more reasonable level.

Objective To evaluate the characteristics and treatment of ovary torsion after controlled ovarian hyperstimulation.Methods Between Jan.2008 and Dec.2011,5 cases with ovary torsion who underwent ovarian hyperstimulation were retrospectively studied.Results Five cases presented intermittent lower abdominal from I to 38 days after oocyte retrieval.Enlargement of ovary and decreased or absent venous and/or arterial flow were demonstrated by Doppler sonography.Two torsions at left side,two torsions at right side,and one on bilateral side were observed.Three cases give up embryo transplantation,2 cases were pregnant after surgical treatment.One case with partial torsion was successfully treated with simple conservative treatment.Two cases with complete torsion were performed adnexectomy by laparotomy.One case with complete torsion with early pregnancy was managed by laparoscopic adnexectomy.One case with chemical pregnancy was managed by laparoscopic detorsion for left side and excision for right side.Postoperative pathology of ovary tissue all confirmed haemorrhage and necrosis.Conclusions Ovary torsion might occur after controlled ovarian hyperstimulation.The early management on ovary torsion will be benefit for preserving ovarian function.