[Establishment of multi-sector collaborative mechanism and surveillance network for Salmonella infection outbreak response and control]

Salmonellosis is one of the common food-borne diseases, local and cross-region outbreaks are not rare. The risk of cross-border transmission of Salmonella is increasing with the high frequency of global economic trades. The recently occurred multi-country outbreaks of Salmonella Typhimurium infection associated with chocolate products have highlighted the importance of improving capability of surveillance and warning of foodborne-disease, especially salmonellosis, in China. It is essential to strengthen the collaboration among clinical medicine, disease control and food safety institutions, improve the capability of whole-genome sequencing of Salmonella for the disease surveillance and tracing, and facilitate the information sharing and collaboration among the food safety related sectors for the timely detection, prevention and control of outbreaks of Salmonella infection in China.

Pyroelectric effect mediated infrared photoresponse in Bi2Te3/Pb(Mg1/3Nb2/3)O3-PbTiO3 optothermal ferroelectric field-effect transistors

The responses of material properties to multi-field stimulation are often exploited to construct new types of multi-functional devices. Here, we demonstrate electrical, optical and thermal modulation of the electronic properties of optothermal ferroelectric field-effect transistors (FeFETs) which are fabricated by growing Bi₂Te₃ films on (111)-oriented 0.71Pb(Mg_1/3Nb_2/3)O₃-0.29PbTiO ₃ (PMN-PT) ferroelectric single-crystal substrates. Using the electric field to switch the polarization direction of PMN-PT, the carrier density and resistance of Bi₂Te₃ films are in situ, reversibly, and nonvolatilely modulated via the ferroelectric field effect. Moreover, through infrared light illumination on the bottom of PMN-PT substrates, the resistance of Bi₂Te₃ films in two polarization states could be further modulated, which is ascribed to the decreased polarization intensity at higher temperature due to the pyroelectric effect. Taking advantage of these two effects, the Bi₂Te₃/PMN-PT optothermal FeFETs exhibit multiple responses to optical and electric field stimulation at room temperature. Our work provides a strategy to design optoelectronic devices with both photodetector and memory functionalities.

[Clinical features of 141 fatal cases of coronavirus disease in Jinyintan Hospital in Wuhan, China]

Objective: To describe the epidemiological characteristics and clinical features of patients with fatal coronavirus disease (COVID-19), in order to provide evidence for clinical diagnosis and treatment. Methods: In this retrospective study, we analyzed data on 141 fatal cases of confirmed COVID-19 that occurred among patients in Jinyintan Hospital in Wuhan, China, from January 20 to March 6, 2020. We analyzed their epidemiological characteristics, clinical and radiological features, laboratory results, and treatment. Results: Of the 141 patients (49 females, 92 males), the median age was 77 years (range: 24-92 years). The most likely source of exposure included the Huanan seafood market (n=3, 2%), family members (n=6, 4%), and hospital-acquired infection (n=8, 6%). The remaining 116 patients (72%) had no known source of exposure. Of the patients, 101 (72%) had chronic diseases. The most common comorbidities were hypertension, diabetes and coronary heart disease. The most common clinical manifestations were fever (n=121, 85%), dry cough (n=77, 54%), shortness of breath (n=23, 16%), and chest pain (n=15, 10%). Less common clinical manifestations included fatigue (n=7, 4%), headache (n=3, 2%), disorders of consciousness (n=2, 1%), diarrhea (n=2, 1%) and lumbago (n=1, 0.7%). In terms of laboratory tests, the absolute value of lymphocytes in most patients was reduced (n=132, 94%), but C-reactive protein (n=141, 100%), procalcitonin(n=121, 89%), serum amyloid (n=140, 99%) were significantly increased. The most common findings on imaging of the lungs were bilateral multiple mottling and ground-glass opacity (n=101, 72%), mainly in the lower lobes (n=15, 10%), with lesions being more common on the right. Other imaging findings included diffuse consolidation (n=4, 3%), ground-glass opacity and consolidation (n=20, 14%), and pneumothorax (n=1, 0.7%). All patients were treated with antibiotics and antiviral drugs. Other treatments included immunoglobulin (n=49, 35%), corticosteroids (n=45, 32%), continuous renal replacement therapy (n=24, 17%), and extracorporeal membrane oxygenation (n=12, 9%). All patients were treated with oxygen therapy. The mode of administration included invasive mechanical ventilation (n=61, 43%), noninvasive mechanical ventilation (n=65, 46%), and nasal catheter oxygen inhalation (n=15, 11%). The direct causes of death were acute respiratory distress syndrome (n=90, 64%), multiple organ failure (n=24, 17%), sudden cardiac arrest (n=11, 8%), viral myocarditis (n=8, 5%), acute myocardial infarction (n=4, 3%), cerebrovascular accident (n=3, 2%), and acute gastrointestinal bleeding (n=1, 0.7%). Conclusions: Risk factors for death due to COVID-19 included older age, male sex, and the presence of comorbidities. The most common direct causes of death were acute respiratory distress syndrome, multiple organ failure, sudden cardiac arrest, and viral myocarditis.

Isoleucine improved growth performance, and intestinal immunological and physical barrier function of hybrid catfish Pelteobagrus vachelli × Leiocassis longirostris

This study was performed to determine effects of dietary isoleucine (Ile) on growth performance, and intestinal immunological and physical barrier function of hybrid catfish Pelteobagrus vachelli × Leiocassis longirostris. Six hundred and thirty fish (33.11 ± 0.09 g) were randomly divided into seven experimental groups with three replicates each, and respectively fed seven diets with 5.0, 7.5, 10.0, 12.5, 15.0, 17.5, and 20.0 g Ile kg^-1 diets for 8 weeks. The results showed improvement of growth performance, feed intake, feed utilization, relative gut length (RGL), and intestinal fold height and width by dietary Ile (P < 0.05). Meanwhile, dietary Ile (12.5 g kg^-1 diet) improved the activities of lysozyme (LZM), acid phosphatase, alkaline phosphatase and the contents of complement 3 (C3), C4, and immunoglobulin M (IgM) (P < 0.05). The c-type-lectin, c-LZM, g-LZM, and hepcidin mRNA expressions in the intestine were up-regulated in fish fed diets with 10.0-20.0 g Ile kg^-1 diet (P < 0.05). Dietary Ile (10.0-12.5 g Ile kg^-1 diet) increased intestinal β-defensin mRNA expression partially in association with Sirt1/ERK/90RSK signaling pathway. Dietary Ile (12.5-15.0 g Ile kg^-1 diet) decreased oxidative damage and improved antioxidant ability by increasing activities and expressions of superoxide dismutase, glutathione peroxidase, and glutathione reductase, glutathione-S-transferase (P < 0.05). The occludin, ZO-1, ZO-2, claudin3, and claudin 7 mRNA expressions in the intestine were up-regulated in fish fed diets with 10.0 and 12.5 g Ile kg^-1 diet (P < 0.05), whereas the myosin light chain kinase gene expression was decreased in fish fed diets with 7.5-17.5 g Ile kg^-1 diet. Dietary Ile (10-12.5 g Ile kg^-1 diet) decreased apoptotic responses by reducing the expression of caspase3 and caspase 9 via the AKT/TOR signaling pathway. Based on the quadratic regression analysis of PWG, the dietary Ile requirement of hybrid catfish was estimated to be 12.43 g Ile kg^-1 diet, corresponding to 32.05 g Ile kg^-1 dietary protein. Collectively, dietary Ile improved growth performance and immunological and physical barrier function of intestine in hybrid catfish.

[Comparison of colonization ability of O1 and O139 Vibrio cholerae strains on soft-shelled turtle's surface]

Objective: To study the preferred colonization sites of O1 Vibrio cholerae (V.cholerae) and the colonization ability difference for O1 and O139 V. cholerae on soft-shelled turtle's surface. Methods: 8 O1 and O139 V. cholerae strains were obtained from branch of diarrheal diseases, Chinese center for disease control and prevention. 63 soft-shelled turtles weighing 150 g and 9 cm in length (diameter of calipash) were selected for use in the study. The preferred colonization sites and proliferation trend were studied by using bioluminescent imaging method. The colonization factors for O1 V. cholerae strains were studied by constructing colonization gene mutant strains (VC1897dmshA, VC1897dgbpA and VC1897dtcpA), performing competition colonization assays and analyzing the competitive indexes. After pairing off O1 and O139 strains respectively to perform 16 competition groups, the colonization difference of these two strains were studied by competition colonization assays. Results: The colonization sites by V. cholerae on soft-shelled turtles surfaces was clustered. More V. cholerae strains colonized on turtle's calipash and carapace on dorsal side and less strain colonized on ventral side. The competition colonization assays showed that colonization ability of O1 serogroup mshA mutant strains were 7.26 times lower than VC1897dlacZ. Besides, the CI value (O139/O1) of 11 out of the 16 competition groups were greater than 2 (between 2.07 and 59.84). Two groups showed values of 1.43 and 0.93 respectively and 3 groups lower than 0.7. Conclusion: The preferred colonization sites for O1 V. cholerae strains on body surface were observed.MSHA was one of the main colonization factors for its colonization. Our study suggested that in general, O139 V. cholerae strains have stronger colonization ability than O1 strains. Besides, strains isolated from soft-shelled turtles tend to have stronger colonization ability than strains isolated from patients.

[Spatial and temporal clustering characteristics of typhoid and paratyphoid fever and its change pattern in 3 provinces in southwestern China, 2001-2012]

Objective: To analyze the spatial and temporal clustering characteristics of typhoid and paratyphoid fever and its change pattern in Yunnan, Guizhou and Guangxi provinces in southwestern China in recent years. Methods: The incidence data of typhoid and paratyphoid fever cases at county level in 3 provinces during 2001-2012 were collected from China Information System for Diseases Control and Prevention and analyzed by the methods of descriptive epidemiology and geographic informatics. And the map showing the spatial and temporal clustering characters of typhoid and paratyphoid fever cases in three provinces was drawn. SaTScan statistics was used to identify the typhoid and paratyphoid fever clustering areas of three provinces in each year from 2001 to 2012. Results: During the study period, the reported cases of typhoid and paratyphoid fever declined with year. The reported incidence decreased from 30.15 per 100 000 in 2001 to 10.83 per 100 000 in 2006(annual incidence 21.12 per 100 000); while during 2007-2012, the incidence became stable, ranging from 4.75 per 100 000 to 6.83 per 100 000 (annual incidence 5.73 per 100 000). The seasonal variation of the incidence was consistent in three provinces, with majority of cases occurred in summer and autumn. The spatial and temporal clustering of typhoid and paratyphoid fever was demonstrated by the incidence map. Most high-incidence counties were located in a zonal area extending from Yuxi of Yunnan to Guiyang of Guizhou, but were concentrated in Guilin in Guangxi. Temporal and spatial scan statistics identified the positional shifting of class Ⅰ clustering area from Guizhou to Yunnan. Class Ⅰ clustering area was located around the central and western areas (Zunyi and Anshun) of Guizhou during 2001-2003, and moved to the central area of Yunnan during 2004-2012. Conclusion: Spatial and temporal clustering of typhoid and paratyphoid fever existed in the endemic areas of southwestern China, and the clustering area covered a zone connecting the central areas of Guizhou and Yunnan. From 2004 to 2012, the most important clustering area shifted from Guizhou to Yunnan. Findings from this study provided evidence for the identifying key areas for typhoid and paratyphoid fever control and prevention and allocate health resources.

[An outbreak of paratyphoid fever in a county of Yunnan province, 2010-2011]

Objective: To identify the source and to comment on control program regarding an outbreak of paratyphoid A fever in a county, through field studies. Methods: Descriptive epidemiological methods were adopted to describe the epidemiological characteristics of the outbreak, which occurred in Yuanjiang county, Yunan province between 2010-2011, China. Case-control study with environmental investigation was performed to identify related risk factors and pathogens while isolation and susceptibility on the suspected pathogens were conducted. Subsequently, intervention and preventive measures were taken for the control of the outbreak. Results: A total of 600 cases were diagnosed and reported as paratyphoid fever A which spread over the whole Yuanjiang county, including 10 townships with different incidence rates. The disease was spatially clustered and the prevalence rates in these townships decreased with increasing distances from the polluted fields. Data from the case-control study discovered that consumption of raw vegetables was the main risk factor associated with this outbreak of paratyphoid fever (OR=65.3, P<0.001). Management of patients did not meet the requirements while feces and urine of the outpatients polluted the wastewater system in the city. Salmonella paratyphi A isolates were identified from the improperly disinfected wastewaters in hospitals and city systems, respectively. After the measures as prohibiting the planting of vegetables in contaminated fields and disinfection of hospital wastewater were taken, the outbreak subsided. Conclusions: Urban and hospital wastewater used for vegetables irrigation together with the tradition of eating uncooked vegetables seemed responsible for the outbreak of this paratyphoid fever. Intervention programs carried by the local government played a key role in controlling this large outbreak.

Human immunodeficiency virus and hepatitis C infections induce distinct immunologic imprints in peripheral mononuclear cells

Coinfection with hepatitis C virus (HCV) is present in one-third of all human immunodeficiency virus (HIV)-infected individuals in the United States and is associated with rapid progression of liver fibrosis and poor response to pegylated interferon (IFN) and ribavirin. In this study we examined gene expression profiles in peripheral blood mononuclear cells (PBMCs) from different groups of individuals who are monoinfected or coinfected with HIV and HCV. Data showed that HIV and HCV viremia up-regulate genes associated with immune activation and immunoregulatory pathways. HCV viremia is also associated with abnormalities in all peripheral immune cells, suggesting a global effect of HCV on the immune system. Interferon-alpha-induced genes were expressed at a higher level in PBMCs from HIV-infected individuals. HCV and HIV infections leave distinct profiles or gene expression of immune activation in PBMCs. HIV viremia induces an immune activated state; by comparison, HCV infection induces immunoregulatory and proinflammatory pathways that may contribute to progression of liver fibrosis.

CONCLUSION

An aberrant type-I IFN response seen exclusively in HIV-infected individuals could be responsible for the poor therapeutic response experienced by HIV/HCV coinfected individuals receiving interferon-alpha-based current standard of care.

TAME-esterase activity during a prolonged attack of asthma

We measured serum N-alpha-tosyl-L-arginine methyl ester (TAME)-esterase activity in a group of patients suffering from a prolonged attack of asthma. Measurements were made pre and post salbutamol nebulization. Our results showed that TAME-esterase activity did not change significantly pre or post nebulization. Based on our experimental data, we concluded that increase serum TAME-esterase activity is a biochemical substance associated with the early asthmatic response but not with prolonged attack of asthma.

Tosyl arginine methyl ester induces bronchoconstriction in rabbit bronchial tissues in vitro: a possible new mediator in asthma

Tosyl arginine methyl ester induced bronchoconstriction in rabbit bronchial rings mounted in vitro with a calculated EC50 of 5.6 x 10(-5) M as compared with acetylcholine which induced sustainable constriction with an EC50 of 2.5 x 10(-6) M. Tosyl arginine methyl ester, however, had definite bronchoconstricting properties though less potent than acetylcholine. We concluded that our data support the hypothesis that tosyl arginine methyl ester could be a possible biochemical mediator of airway contraction.

[Renal pelvic tumor associated with contralateral renal cyst--a case report]

A 74-year-old female presented with a two years history of malaise, weakness and intermittent gross hematuria. Two years earlier, left renal cyst had been diagnosed by excretory urography, abdominal sonography and computed-tomography. Initially she was treated conservatively with oral antibiotics, however medical management had not been successful in improving her condition. Finally she was transfer to our ward for further evaluation and treatment. Cystoscopic examination demonstrated no abnormality, except for bloody urine efflux from the right ureteric orifice. Right retrograde pyelograms confirmed a solitary filling defect in the upper calyx of right kidney. Because of immediate concern for right renal pelvic tumor and contralateral renal cyst, a midline transperitoneal exploration was made. The right nephroureterectomy with cuff of bladder was removed and left unroofing of cyst was carried out. Convalescence was uneventful. The pathologic examination revealed moderately differentiated transitional cell carcinoma of right kidney with a simple renal cyst of left kidney. We suggest that cases with a clinical diagnosis of renal cyst based on the presence of gross hematuria, a normals excretory urogram and computed tomogram, generally require further evaluation especially by cystoscope and retrograde pyelogram to determine the source of bleeding.

Thiol peroxyl radical formation from the reaction of cysteine thiyl radical with molecular oxygen: an ESR investigation

Using Electron Spin Resonance (ESR) spectroscopy, we have identified the cysteine thiol peroxyl radical (CysSOO.) at low temperatures in two aqueous glasses. This radical shows a typical peroxyl radical ESR spectrum, but unlike carbon-based peroxyl radicals has a violet color (lambda max = 540 nm) and forms a new radical showing a singlet ESR spectrum when photobleached with visible light. The cysteine peroxyl radical reacts to form the cysteine sulfinyl radical (CysSO.) in the glass which allows warming to 165K. 17O isotopic substitution studies indicate dissolved molecular oxygen is the source of oxygen in CysSOO.. Anisotropic g-values and the parallel anisotropic 17O hyperfine couplings for this radical are reported.