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Objective:To investigate the phylogenetic and antigenic characteristics of hemagglutinin (HA) gene of influenza B/Victoria lineage (BV) viruses in Beijing during the 2021-2022 influenza surveillance season, and to analyze whether the circulating BV viruses match the vaccine strain.Methods:Pharyngeal swab specimens from influenza like-illness (ILI) cases in the 2021-2022 influenza surveillance season were collected from surveillance network labs in Beijing and cultured in MDCK cells and chicken embryo to isolate BV viruses. Nucleic acids of the viruses were extracted, and the HA gene was amplified and sequenced. The nucleotide and amino acid sequence identity of the HA gene was analyzed using MEGA5.0 software. A phylogenetic tree of HA gene was constructed using the maximum likelihood method. The N-glycosylation sites in HA were predicted online. Three-dimensional structure of HA was constructed using SWISS-MODEL homologous modeling. Hemagglutination inhibition (HI) test was performed to analyze the antigenicity of BV viruses.Results:A total of 402 BV viruses were collected and 58 strains with full-length HA gene sequences were chosen for further analysis. Compared with the HA gene of this year′s vaccine strain (B/Washington/02/2019), there were 27 amino acid mutations, 11 of which were located in four different antigenic determinants. The phylogenetic analysis revealed that three subgroups of 1A.3, 1A.3a1, and 1A.3a2 co-circulated in Beijing with 54 strains (54/58, 93.10%) clustered to the Clade 1A.3a2, two strains (2/58, 3.45%) clustered to the Clade 1A.3a1, and two strains (2/58, 3.45%) in the same subgroup (Clade 1A.3) as the vaccine component BV strain in 2021-2022. Compared with the vaccine strain (B/Washington/02/2019), two BV strains had an additional N-glycosylation site at residue 197, while the other 56 strains showed no change in N-glycosylation sites. Antigenic analysis showed that 35 BV strains (35/58, 60.34%) were antigenically similar to the vaccine strain and 23 strains (23/58, 39.66%) were low-response strains.Conclusions:Three subgroups of BV viruses co-circulated in Beijing during the 2021-2022 influenza surveillance season. The predominant subgroup was Clade 1A.3a2 (93.10%), showing a certain genetic distance with the vaccine strain (B/Washington/02/2019). Nearly 40% (39.66%) of the viruses were low-response strains. This study indicated that continuous monitoring of the variations of influenza epidemic strains and timely providing laboratory basis for screening vaccine component strains were the basic technical guarantee for coping with influenza pandemic.
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Objective:To clarify the M protein ( emm gene) types and drug susceptibility characteristic variations of Group A Streptococcus (GAS) in children in Beijing. Methods:The GAS strains isolated from throat swab samples of children diagnosed with scarlet fever and pharyngeal infection in scarlet fever etiology surveillance sentinel hospitals in 16 districts of Beijing in 2018, 2019 and 2021 were analyzed retrospectively.PCR amplification and sequencing were used for emm genotyping, and the minimum inhibitory concentrations (MIC) of 10 antibiotics were determined by the broth microdilution method.The data were analyzed using χ2 test and Fisher′ s exact method between groups. Results:A total of 557 GAS strains were collected, and 11 emm genotypes ( emm1, emm3, emm4, emm6, emm11, emm12, emm22, emm75, emm89, emm128, and emm212) were detected.Of 557 strains, 238 trains were of emm1 type (42.73%), 271 strains were of emm12 type (48.65%) and 48 strains were of other emm types (8.62%). The detection rates of emm1, emm12 and other emm type genes in 2018, 2019, and 2021 were [37.50% (105/280 strains), 57.14% (160/280 strains), 5.36% (15/280 strains)], [49.05% (129/263 strains), 39.54% (104/263 strains), 11.41% (30/263 strains)], and [28.57% (4/14 strains), 50.00% (7/14 strains), 21.43% (3/14 strains)], respectively.In children infected with emm12 in 2018 and 2019, there were more children under 6 years old than children over 6 years old (62.50% vs.46.88%, 46.36% vs.30.36%) (χ 2=7.182, 6.973; all P<0.05). Drug susceptibility testing results suggested that 225 randomly selected GAS strains were all 100.00% sensitive to 7 antibiotics including Penicillin, Levofloxacin, Meropenem, Linezolid, Cefotaxime, Cefepime and Vancomycin.The rates of resistance to Erythromycin, Tetracycline and Clindamycin were [88.57% (93/105 strains), 87.62% (92/105 strains), 86.67% (91/105 strains)], and [94.34% (100/106 strains), 94.34% (100/106 strains), 87.74% (93/106 strains)] in 2018 and 2019, respectively.The test strains were 100.00% (14/14 strains) resistant to the above 3 antibiotics in 2021.MIC 50 and MIC 90 values of Penicillin in 2018, 2019, and 2021 were (0.03 mg/L, 0.03 mg/L), (0.03 mg/L, 0.06 mg/L), and (0.06 mg/L, 0.06 mg/L), respectively.Among 225 GAS strains, 207 strains had drug resistance and were resistant to more than one drug.Specifically, 94.69% (196/207 strains) were resistant to Erythromycin, Tetracycline and Clindamycin.About 4.35% (9/207 strains) were resistant to both Erythromycin and Clindamycin.A total of 0.97% (2/207 strains) were resistant to Erythromycin and Tetracycline. Conclusions:The emm genotypes of GAS in children in Beijing are diverse in 2018, 2019 and 2021.The dominant genotypes are emm12 and emm1, and emm12 is the main epidemiological type.GAS strains maintain highly resistant to Erythromycin, Clindamycin and Tetracycline, and sensitive to Penicillin and other antibiotics.However, MIC 50 and MIC 90 of Penicillin shows an ascending trend.
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Objective To investigate the protective effect of adult human liver-derived stem cell exosomes (HLSC-exo) intravenously injected at different time points against acute liver injury induced by concanavalin A (ConA) in mice. Methods HLSC-exo was extracted by differential centrifugation. Western blot was used to measure the expression of the marker proteins CD9 and CD63, and nanoparticle tracking analysis was used to investigate particle size distribution. A total of 56 male C57BL/6 mice were randomly divided into blank control group, ConA model group, and HLSC-exo treatment group. The ConA model group and the HLSC-exo treatment group were further divided into 3-, 6-, and 12-hour subgroups according to the interval between phosphate buffer or HLSC-exo injection and ConA injection. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) were measured, and the gross morphology and histopathology of the liver were compared between groups. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups. Results HLSC-exo was a membranous vesicle with a diameter of 90-110 nm, with a clear saucer-like structure under an electron microscope and marked expression of its specific marker proteins CD9 and CD63. In the blank control group, the levels of ALT and AST were 31.81±6.74 U/L and 69.75±8.30 U/L, respectively. Compared with the blank control group, the 3-, 6-, and 12-hour ConA model groups had significant increases in the levels of ALT and AST (all P < 0.001); compared with the 3-and 6-hour ConA model groups, the 3-and 6-hour HLSC-exo treatment groups had significant reductions in the levels of ALT and AST (225.58±115.59 U/L vs 1989.32±347.67 U/L, 1174.71±203.30 U/L vs 2208.33±349.96 U/L, 303.53±126.68 U/L vs 2534.27±644.72 U/L, 1340.70±262.56 U/L vs 2437.13±288.13 U/L, all P < 0.001); compared with the 6-hour HLSC-exo treatment group, the 3-hour HLSC-exo treatment group had significantly greater reductions ( P < 0.001). In the blank group, the levels of IL-10 and TNF-α were 313.51±10.97 pg/ml and 476.05±7.31 pg/ml, respectively. Compared with the blank control group, the 3-, 6-, and 12-hour ConA model groups had a significant reduction in the level of IL-10 (all P < 0.001); compared with the 3-and 6-hour ConA model groups, the 3-and 6-hour HLSC-exo treatment groups had a significant increase in the level of IL-10(331.61±10.46 pg/ml vs 266.20±8.15 pg/ml, 288.13±10.74 pg/ml vs 264.41±9.12 pg/ml, both P < 0.001); compared with the 6-hour HLSC-exo treatment group, the 3-hour HLSC-exo treatment group had a significantly greater increase ( P < 0.001). Compared with the blank control group, the 3-, 6-, and 12-hour ConA model groups had a significant increase in the level of TNF-α (all P < 0.001); compared with the 3-and 6-hour ConA model groups, the 3-and 6-hour HLSC-exo treatment groups had a significant reduction in the level of TNF-α (478.26±12.99 pg/ml vs 551.31±17.70 pg/ml, 515.58±7.18 pg/ml vs 556.21±11.15 pg/ml, both P < 0.001); compared with the 6-hour HLSC-exo treatment group, the 3-hour HLSC-exo treatment group had a significantly greater reduction ( P < 0.001). Compared with the 3-and 6-hour ConA model groups in terms of the gross morphology and histopathology of the liver, the 3-and 6-hour HLSC-exo treatment groups had a significant reduction in the degree of hepatocyte necrosis, and the 3-hour HLSC-exo treatment group had a basically complete lobular structure, with sporadic spotty necrosis; the 12-hour HLSC-exo treatment group had no significant improvement in hepatocyte necrosis compared with the 12-hour ConA model group. Conclusion Intravenous injection of adult HLSC-exo can alleviate acute liver injury induced by ConA in mice, and injection at 3 hours in advance has the most significant protective effect. Regulation of cytokines is one of the important mechanisms for HLSC-exo to alleviate liver injury.
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Objective:To analyze the imaging characteristics of invasive fibromatosis from breast parenchyma, and to explore the clinical value of multimodal ultrasound.Methods:The two-dimensional, color Doppler and elastic imaging sonographic manifestations and pathological features of 12 cases of breast invasive fibromatosis included in the Affiliated Hospital of Jining Medical College from October 2015 to October 2020 were studied retrospectively.Results:Two dimensional ultrasound showed that 12 cases of breast invasive fibromatosis grew in parallel, with different sizes, unclear boundary and no complete capsule. The edge morphology of 7 cases (7/12) showed crab foot like changes; The tumor showed solid heterogeneous hypoechoic, punctate hyperechoic in 3 cases (3/12), and echo attenuation behind the tumor in 3 cases (3/12); The blood flow in the tumor was mainly grade 1-2 (9/12). Twelve tumors were examined quantitatively by virtual touch tissue quantifification. The shear wave velocity was (3.08±0.75)m/s. The diagnostic accuracy of multimodal ultrasound in invasive fibromatosis of breast (10/12) was significantly higher than that of conventional ultrasound (3/12, χ 2=8.224, P=0.004). The gross manifestation of the tumor: the section was gray or gray yellow, with unclear boundary and no capsule; Microscopic findings: fascicular fibroblasts and myofibroblasts proliferated, accompanied by varying degrees of glassy degeneration, acellular atypia, nuclear division and necrosis. Conclusions:Conventional ultrasound is difficult to distinguish invasive fibromatosis and malignant tumor of breast, and its ultrasonic manifestations are closely related to pathological features. The combined application of multimodal ultrasound can significantly improve the diagnostic coincidence rate of the disease and has high clinical application value.
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Objective:To observe the etiological distribution, clinical presentations and imaging features of pulmonary mycosis that is diagnosed by pathology.Methods:The etiological distribution, clinical presentations and imaging features of patients with pulmonary mycosis, who were collected in the Affiliated Hospital of Jining Medical University from January 2018 to July 2020, were retrospectively analyzed. The diagnosis of all the patients were confirmed by pathological examination, of lung or bronchi tissue that were obtained through operation, bronchoscope or percutaneous lung puncture biopsy.Results:There were 26 patients' (60.47%, 26/43) pathological specimens were obtained by operation, 14 cases (32.56%, 14/43) were obtained by bronchoscope, and 3 cases (6.98%, 3/43) were obtained by percutaneous lung puncture biopsy. Of the 43 patients who were diagnosed pulmonary mycosis by pathology, 27 patients (62.79%, 27/43) suffered from pulmonary aspergillosis, 11 patients (25.58%, 11/43) suffered from pulmonary cryptococcosis, 3 patients (6.98%, 3/43) suffered from pulmonary mucormycosis, and 2 patients (4.65%, 2/43) suffered from pulmonary candidiasis. There were 27 patients (62.79%, 27/43) with pulmonary fungal disease complicating risk factors of fungal infection, including diabetes mellitus (23.26%,10/43), malignant tumor (16.28%, 7/43), bronchiectasis (9.30%, 4/43), hepatitis B virus (HBV) carrier (6.98%, 3/43), taking glucocorticoids (4.65%, 2/43), pulmonary tuberculosis (4.65%, 2/43), and chemotherapy following colon carcinoma operation (2.33%, 1/43). The common clinical presentations included cough (55.81%, 24/43), expectoration (48.84%, 21/43), hemoptysis (37.21%, 16/43), fever (20.93%, 9/43), gasping (18.60%, 8/43), chest pain (16.28%, 7/43), and hoarseness (3.13%, 1/43). Imaging features of chest included lung nodes in 20 cases (46.51%, 20/43), vascular welt sign in 12 cases (27.91%, 12/43), exudative process in 10 cases (23.26%, 10/43), lung mass or consolidation in 8 cases (18.60%, 8/43), cavitary lesions in 7 cases (16.28%, 7/43), thicken bronchus wall and narrow lumina in 6 cases (13.95%, 6/43), air crescent in 5 cases (11.63%, 5/43).Conclusions:The pulmonary aspergillosis and cryptococcosis are mainly in pulmonary mycosis diagnosed by pathology. The common complications are diabetes mellitus and malignant tumor. The common clinical presentations are cough, expectoration, and hemoptysis. The main imaging features of chest are lung nodes and vascular welt sign can be found in most of pulmonary cryptococcosis.
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Objective To establish a new patient-derived xenograft (PDX) model of human liver cancer by inoculating the complex of human primary liver cancer cells and a novel microcarrier (microcarrier 6) into mice with normal immune function. Methods Primary liver cancer cells were isolated and extracted from the fresh human liver cancer tissue of five patients and were then co-cultured with microcarrier 6 to construct a three-dimensional tumor cell culture model in vitro . According to the type of graft, 75 male C57BL/6 mice were divided into cell control group, microcarrier control group, and experimental group (each sample corresponded to three groups, with 15 groups in total and 5 mice in each group). The liver cancer cell-microcarrier complex was implanted into the mice by subcutaneous inoculation, and tumor formation time, tumor formation rate, and histopathological manifestations were observed. The Fisher's exact test was used for comparison of categorical data between two groups. Results As for the liver cancer cells from the five patients, tumor formation was observed in the mice corresponding to three patients. In these three experiments, tumor formation was not observed in the control groups and was only observed in the experimental groups, and 12 of the 15 mice in the experimental groups had successful tumor formation, with a tumor formation rate as high as 80%, which was significantly different from that in the cell control groups and the microcarrier control groups (all P < 0.05). The tumor formation time was 5-7 days; the xenograft tumor grew rapidly, and HE staining showed nested or flaky cells with obvious heteromorphism, with the presence of pathological mitosis; immunohistochemical staining showed positive CK8/18, Hep, and Gpc-3, which was in accordance with the characteristics of human liver cancer cells. Conclusion This experiment successfully establishes a new PDX model of human liver cancer based on the complex of microcarrier 6 and human primary liver cancer cells in mice with normal immunity. This model can be used to better elucidate the mechanism of the development and progression of liver cancer in the body with normal immunity, and besides, it also provides a new animal model with higher value for the precise treatment of liver cancer.
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Objective:To analyze the prevalence of goiter among children aged 8 to 10 years old in Beijing and study the influencing factors of goiter in children.Methods:In 16 districts of Beijing, each district was divided into 5 sampling districts according to east, west, south, north and middle locations in 2018. One town/street was selected from each sampling district, one primary school was selected from each town/street, and 40 non-boarding students aged 8 to 10 years old were selected from each primary school. The size of thyroid was measured by B-ultrasound method, the volume of thyroid was calculated and whether goiter or not was determined according to the "Diagnostic Criteria for Endemic Goiter". Random urine samples were collected, urinary iodine was detected by arsenic-cerium catalytic spectrophotometry. Height and weight were measured, body mass index (BMI) was calculated, and the correlation of thyroid volume with height and weight was analyzed.Results:A total of 3 268 children were surveyed, in which 154 children with goiter; the goiter rate was 4.7%. The goiter rate in girls [5.7% (93/1 641)] was higher than that in boys [3.7% (61/1 627), χ 2 = 6.694, P < 0.05]. The goiter rates of children aged 8, 9 and 10 years old were 4.3% (15/346), 5.5% (85/1 534) and 3.9% (54/1 388), respectively, there was no significant difference between the ages (χ 2 = 4.544, P > 0.05). The median of urinary iodine in children was 175.3 μg/L, which was in an iodine appropriate level. The thyroid volumes of children aged 8, 9 and 10 years old were positively correlated with height and weight ( r = 0.143, 0.225, 0.323, 0.338, 0.321, 0.346, P < 0.01). Conclusion:The goiter rate of children in Beijing is high, children's thyroid volume is greatly affected by height and weight, and it is recommended to consider the influence of height and weight when study the diagnostic criteria of children's goiter.
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Objective To explore the effects of facial asymmetry on stress distributions in temporomandibular joints (TMJs) for patients with mandibular prognathism. Methods Eight 3D maxillofacial models were established in MIMICS based on cone-beam CT of 4 mandibular prognathism patients with asymmetry and 4 mandibular prognathism patients without asymmetry. Muscle forces and boundary conditions corresponding to the unilateral occlusion (unilateral molar chewing) were applied on the models in ABAQUS. The maximum and the minimum principal stresses of TMJ were chosen for analysis. Results There were significant differences in the maximum and minimum principal stresses at the condyles between the mandibular prognathism patients with and without facial asymmetry under unilateral occlusions (P<0-05). Compared with patients without facial asymmetry, the stresses on the condyle in patients with asymmetry increased by 2-3 times, and the stresses on articular fossa increased by 5-7 times. Among the mandibular prognathism patients with asymmetry, the stresses of the ipsilateral TMJ in patients with temporomandibular disorder (TMD) were significantly higher than those in patients without TMD. Conclusions Facial asymmetry increased the stresses of the articular fossa and condyle in patients with mandibular prognathism. TMD would cause greater stresses in ipsilateral TMJ of the mandibular prognathism patient with asymmetry. Therefore, different treatment strategies should be considered for mandibular prognathism with facial asymmetry.
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Objective@#To understand the antigenicity and genetic characterization of influenza B virus HA gene in B/Victoria-lineage virus (BV) in Beijing during 2017-2018.@*Methods@#Thirty BV virus strains isolated from MDCK cell culture by 17 laboratories in Beijing were collected. The antigenicity was analyzed by comparing with the vaccine strain recommended by WHO. The total viral nucleic acid was extracted and HA gene was amplified by RT-PCR and sequenced. The phylogenetic tree was constructed by HA and mutant sites were analyzed.@*Results@#Among 30 strains of BV, 23 strains (76.7%) were low-reactive strains, other 7 strains (23.3%) were related to the vaccine. The phylogenetic analysis showed that the HA gene of all 30 strains located in Clade 1A branch. In addition, amino acid mutations occurred in 8 sites, and 6 of them located in the antigen determining region.@*Conclusions@#There was a correlation between the high proportion of low-reactive antigenicity and 6 aa variation in antigenic determinants involved in HA region of BV influenza virus between 2017-2018, which provides an important laboratory basis for the recommendation of BV influenza vaccine.
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Objective@#To analyze the influencing factors of acute gastroenteritis outbreaks caused by norovirus in Beijing from 2014 to 2018.@*Methods@#Data of acute gastroenteritis events caused by norovirus in Beijing from April 2014 to March 2018 were collected. Unconditional logistic regression model was conducted to identify the risk factors of the outbreaks.@*Results@#A total of 765 acute gastroenteritis epidemics caused by norovirus were reported in Beijing, in which 85.88% (657/765) were cluster events and 14.12% (108/765) were outbreaks. Among the outbreaks, 70.37% (76/108) were reported in 2017; 84.26% (91/108) were reported in winter and spring; 88.89% (96/108) were reported in kindergartens, primary or secondary schools; 81.48% (88/108) were through person-to-person transmission; 93.52% (101/108) were caused by norovirus GⅡ infection. The risk of outbreaks in suburban and out suburb area were 1.84 times (95%CI: 1.13-3.02) and 3.78 times (95%CI: 1.62-8.82) as high as that in urban area, respectively. The risks of outbreaks in primary, secondary schools and other institutions were 6.26 times (95%CI: 3.53-11.10), 14.98 times (95%CI: 6.23-36.01) and 8.71 times (95%CI: 3.07-24.71) as high as that in kindergartens, respectively. The risk of outbreak in which patients having lower hospital visiting rate than the median rate of all events was 2.29 times than that in the context of having higher hospital visiting rate (95%CI:1.42-3.68). The risk of foodborne outbreak was 14.55 times as high as that transmitted through person-to-person (95%CI: 3.15-67.07).@*Conclusion@#Measures such as strengthening the prevention and control of norovirus outbreaks in suburbs, primary schools, secondary schools and other institutions, promoting patients to visit the hospital actively, improving the management of foodborne events and kitchen workers should be taken to reduce the incidence of acute gastroenteritis outbreaks caused by norovirus.
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Objective To analyze the pathogenic surveillance programs and related factors on bacillary dysentery in Beijing,2008-2017,to provide evidence for the practices of diagnosis,treatment and prevention of the disease.Methods Analysis was conducted on surveillance data of bacillary dysentery,collected from the surveillance areas of national bacillary dysentery in Beijing.Shigella positive rate of stool samples were used as the gold standard while detection rate of Shigella,diagnostic accordance rate and resistance were computed on data from the surveillance programs.Chi-square test was used to compare the rates and unconditional logistic regression was used to analyze the related factors of Shigella infection.Results Both the reported incidence rate on bacillary dysentery and detection rate of Shigella in diarrhea patients showed significantly decreasing trend,from 2008 to 2017.The accordance rate of bacillary dysentery was only 7.80％ (111/1 423).Shigella sonnei was the most frequently isolated strain (73.95％,159/215) followed by Shigella flexnery.Results from the multivariate logistic regression of Shigella positive rate revealed that among those patients who were routine test of stool positive vs.routine test of stool positive (OR=1.863,95％CI:1.402-2.475),onset from July to October vs.other months' time (OR=7.271,95％CI:4.514-11.709) temperature ≥38 ℃ vs.temperature ＜38 ℃ (OR=4.516,95％CI:3.369-6.053) and age from 6 to 59 years old vs.other ages (OR =1.617,95 ％ CI:1.085-2.410),presenting higher positive detection rates of Shigella from the stool tests.The resistant rates on ampicillin and nalidixic acid were 97.57％ (201/206) and 94.90％ (186/196),both higher than on other antibiotics.The resistant rates on ciprofloxacin (16.33％,32/196),ofloxacin (9.57％,11/115) and on amoxilin (15.05％,31/206) were relatively low.The resistant rate appeared higher on Shigellaflexnery than on Shigella sonnei.The proportion of strains with resistance on 3 more drugs,was 30.00％ (21/70).Conclusions The diagnostic accordance rate of bacillary dysentery in Beijing was low,with severe resistance of Shigella.Our findings suggested that clinicians should take multiple factors into account in their practices about epidemiological history,clinical symptom and testing results for diarrhea patients.
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Objective To understand the epidemiological and etiological characteristics of outbreaks on acute gastroenteritis caused by sapovirus (SaⅤ) worldwide.Methods Literature about the outbreaks on acute gastroenteritis caused by SaⅤ were retrieved from the databases including WanFang,CNKI,PubMed and Web of Science after evaluation.Time,geography,setting and population distributions of outbreaks,transmission mode,SaⅤ genotype and clinical characteristics of the patients were analyzed.Results A total of 34 papers about SaⅤ were included,involving 146 outbreaks occurred between October 1976 and April 2016.In these papers,138 outbreaks were reported on the related months.All these outbreaks occurred in northern hemisphere.SaⅤ outbreaks occurred all year around,but mainly in cold season,the incidence was highest in December (25 outbreaks) and lowest in in August (2 outbreaks).Most outbreaks were reported by Japan,followed by Canada,the United States of America and the Netherlands.There were 141 outbreaks for which the occurring settings were reported,child-care settings were most commonly reported setting (48/141,34.04％),followed by long-term care facility (41/141,29.08％) and hospital (16/141,11.35％).Clinical symptoms of 1 704 cases in 31 outbreaks were reported,with the most common symptom was diarrhea (1 331/1 704,78.12％),followed by nausea (829/1 198,69.20％),abdominal pain (840/1 328,63.25％),vomiting (824/1 704,48.36％) and fever (529/1 531,34.53％).Genotypes of SaⅤ were determined for 119 outbreaks.GⅠ (51/119,42.86％) and GⅣ (45/119,37.82％) were predominant.The outbreaks of G Ⅳ SaⅤ increased suddenly in 2007,and the outbreaks of G Ⅰ SaⅤ mainly occurred in 2008 and during 2011-2013.Conclusions SaⅤ outbreaks were reported mainly by developed countries,with most outbreaks occurred in cold season,in child-care settings and long term care facility.G Ⅰ and GⅣ were the most common genotypes of SaⅤ.Prevention and control of SaⅤ outbreak in China seemed relatively weak,and it is necessary to conduct related training and to strengthen the SaⅤ outbreak surveillance in areas where service is in need.
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Objective To analyze the pathogenic surveillance programs and related factors on bacillary dysentery in Beijing,2008-2017,to provide evidence for the practices of diagnosis,treatment and prevention of the disease.Methods Analysis was conducted on surveillance data of bacillary dysentery,collected from the surveillance areas of national bacillary dysentery in Beijing.Shigella positive rate of stool samples were used as the gold standard while detection rate of Shigella,diagnostic accordance rate and resistance were computed on data from the surveillance programs.Chi-square test was used to compare the rates and unconditional logistic regression was used to analyze the related factors of Shigella infection.Results Both the reported incidence rate on bacillary dysentery and detection rate of Shigella in diarrhea patients showed significantly decreasing trend,from 2008 to 2017.The accordance rate of bacillary dysentery was only 7.80％ (111/1 423).Shigella sonnei was the most frequently isolated strain (73.95％,159/215) followed by Shigella flexnery.Results from the multivariate logistic regression of Shigella positive rate revealed that among those patients who were routine test of stool positive vs.routine test of stool positive (OR=1.863,95％CI:1.402-2.475),onset from July to October vs.other months' time (OR=7.271,95％CI:4.514-11.709) temperature ≥38 ℃ vs.temperature ＜38 ℃ (OR=4.516,95％CI:3.369-6.053) and age from 6 to 59 years old vs.other ages (OR =1.617,95 ％ CI:1.085-2.410),presenting higher positive detection rates of Shigella from the stool tests.The resistant rates on ampicillin and nalidixic acid were 97.57％ (201/206) and 94.90％ (186/196),both higher than on other antibiotics.The resistant rates on ciprofloxacin (16.33％,32/196),ofloxacin (9.57％,11/115) and on amoxilin (15.05％,31/206) were relatively low.The resistant rate appeared higher on Shigellaflexnery than on Shigella sonnei.The proportion of strains with resistance on 3 more drugs,was 30.00％ (21/70).Conclusions The diagnostic accordance rate of bacillary dysentery in Beijing was low,with severe resistance of Shigella.Our findings suggested that clinicians should take multiple factors into account in their practices about epidemiological history,clinical symptom and testing results for diarrhea patients.
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Objective To understand the epidemiological and etiological characteristics of outbreaks on acute gastroenteritis caused by sapovirus (SaⅤ) worldwide.Methods Literature about the outbreaks on acute gastroenteritis caused by SaⅤ were retrieved from the databases including WanFang,CNKI,PubMed and Web of Science after evaluation.Time,geography,setting and population distributions of outbreaks,transmission mode,SaⅤ genotype and clinical characteristics of the patients were analyzed.Results A total of 34 papers about SaⅤ were included,involving 146 outbreaks occurred between October 1976 and April 2016.In these papers,138 outbreaks were reported on the related months.All these outbreaks occurred in northern hemisphere.SaⅤ outbreaks occurred all year around,but mainly in cold season,the incidence was highest in December (25 outbreaks) and lowest in in August (2 outbreaks).Most outbreaks were reported by Japan,followed by Canada,the United States of America and the Netherlands.There were 141 outbreaks for which the occurring settings were reported,child-care settings were most commonly reported setting (48/141,34.04％),followed by long-term care facility (41/141,29.08％) and hospital (16/141,11.35％).Clinical symptoms of 1 704 cases in 31 outbreaks were reported,with the most common symptom was diarrhea (1 331/1 704,78.12％),followed by nausea (829/1 198,69.20％),abdominal pain (840/1 328,63.25％),vomiting (824/1 704,48.36％) and fever (529/1 531,34.53％).Genotypes of SaⅤ were determined for 119 outbreaks.GⅠ (51/119,42.86％) and GⅣ (45/119,37.82％) were predominant.The outbreaks of G Ⅳ SaⅤ increased suddenly in 2007,and the outbreaks of G Ⅰ SaⅤ mainly occurred in 2008 and during 2011-2013.Conclusions SaⅤ outbreaks were reported mainly by developed countries,with most outbreaks occurred in cold season,in child-care settings and long term care facility.G Ⅰ and GⅣ were the most common genotypes of SaⅤ.Prevention and control of SaⅤ outbreak in China seemed relatively weak,and it is necessary to conduct related training and to strengthen the SaⅤ outbreak surveillance in areas where service is in need.
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Objective@#To explore the virulence related risk factors based on the enterovirus A71 (EV-A71) genome.@*Methods@#The pairwise distance of each section of gene between mild and fatal cases was analyzed. The ⅴ domain of 5′UTR from mild and fatal cases in this study were constructed. Amino acid sequences of EV-A71 were analyzed to find the potential virulence regions which were statistically different between fatal and mild cases.@*Results@#The two EV-A71 genome sequences in this study belonged to C4a genotype with the genomic homology of 96.2%-97.5%. The nucleotides in the ⅴ domains of the 5 ′UTR of EV-A71 from mild and fatal cases were the same. Each gene of EV-A71 from 31 mild cases and 30 fatal cases shared high homology. A total of four potential virulence sites (2 A: R68 M、2C: K41R、3 A: T/V47 A and 3C: I158 V) which were significantly different between mild cases and fatal cases were obtained.@*Conclusions@#The four sites in the unstructured protein coding region might be related with the virulence of EV-A71.
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Objective@#The objective was to identify the incidence of influenza-like syndromes and related health behavior factors among Beijing residents.@*Methods@#From December 6, 2013 to January 16, 2014, we selected 150 villages or communities from 30 towns or streets as survey locations using a multi-stage random sampling method, and then conducted a cross-sectional study among 7 354 residents who aged 18 years or above and had live in Beijing for more than a half year using self-administered anonymous questionnaires, and totally 7 327 valid questionnaires are collected. The questionnaire consisted of demographic information, self-reported influenza-like syndromes in the past two weeks, and health behaviors. Multiple logistic regression models were used to identify the factors associated with self-reported influenza-like syndromes.@*Results@#The mean (SD) age of the partcipants was 44.6 (15.2) years. Among them, 6.9% (506 cases) reported having influenza like illness during the past two weeks. The multiple logistic regression analysis indicated that regular physical exercise, optimal hand hygiene, and avoidance of going to the crowded places during respiratory infectious disease epidemics were significantly associated with a lower likelihood of reporting influenza-like syndromes, compared with those without regular physical exercises, without optimal hand hygiene, and not avoiding going to the crowded places, and the OR(95%CI) were 0.80 (0.66-0.97), 0.75 (0.57-0.99) and 0.80 (0.65-0.98), respectively.@*Conclusion@#Personal health behaviors were associated with the incidence of respiratory infectious diseases such as influenza in Beijing, and future interventions to improve personal hygiene behaviors are needed to prevent the spread of respiratory infectious diseases.
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Objective To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS),isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017.Methods Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS.Eleven currently known SAg genes including SpeA,speC,speG,speH,speI,speJ,speK,speL,speM,smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR.Results A total of 377 GAS were isolated from 6 801 throat swab specimens,with the positive rate as 5.5％.There were obvious changes noticed among speC,speG,speH and speK in three years.A total of 45 SAg genes profiles were observed,according to the SAgs inclusion.There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emml and emml2 strains (x2=38.196,P＜0.001;x 2=72.310,P＜0.001).There also appeared significant differences in the frequencies of speA,speH,speI and speJ between emm 1 and emm 12 strains (x2 =146.154,P＜ 0.001;x2=52.31,P＜0.001;x2=58.43,P＜0.001;x2=144.70,P＜0.001).Conclusions Obvious changes were noticed among SAg genes including speC,speG,speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017.SAg genes including speA,speH,speI and speJ appeared to be associated with the emm 1 and emm 12 strains.More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles,during the epidemic period.
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Objective To establish a classified evaluation system for recognizing the levels of influenza epidemics and to explore the new reporting system on influenza epidemics.Methods The following 3 indicators,including 1) the number of influenza-like illness,2) positive rate of detection on influenza virus nucleic acids,and 3) the number of influenza outbreaks were chosen to calculate the synthetic index and to classify the grades of evaluation.Results 209 weeks during 2013-2017 were classified into 5 grades:Grade 1 were 110 weeks (52.63％),Grade 2 were 47 weeks (22.49％),Grade 3 were 44 weeks (21.05％),Grade 4 were 8 weeks (3.83％),and Grade 5 were 0 week.Conclusion This classified evaluation system provided simple,comprehensive and comparable reference indicators and used for the evaluation on influenza epidemics,also providing suggestions for influenza prevention and control accordingly.
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Objective To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS),isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017.Methods Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS.Eleven currently known SAg genes including SpeA,speC,speG,speH,speI,speJ,speK,speL,speM,smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR.Results A total of 377 GAS were isolated from 6 801 throat swab specimens,with the positive rate as 5.5％.There were obvious changes noticed among speC,speG,speH and speK in three years.A total of 45 SAg genes profiles were observed,according to the SAgs inclusion.There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emml and emml2 strains (x2=38.196,P＜0.001;x 2=72.310,P＜0.001).There also appeared significant differences in the frequencies of speA,speH,speI and speJ between emm 1 and emm 12 strains (x2 =146.154,P＜ 0.001;x2=52.31,P＜0.001;x2=58.43,P＜0.001;x2=144.70,P＜0.001).Conclusions Obvious changes were noticed among SAg genes including speC,speG,speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017.SAg genes including speA,speH,speI and speJ appeared to be associated with the emm 1 and emm 12 strains.More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles,during the epidemic period.
ABSTRACT
Objective To establish a classified evaluation system for recognizing the levels of influenza epidemics and to explore the new reporting system on influenza epidemics.Methods The following 3 indicators,including 1) the number of influenza-like illness,2) positive rate of detection on influenza virus nucleic acids,and 3) the number of influenza outbreaks were chosen to calculate the synthetic index and to classify the grades of evaluation.Results 209 weeks during 2013-2017 were classified into 5 grades:Grade 1 were 110 weeks (52.63％),Grade 2 were 47 weeks (22.49％),Grade 3 were 44 weeks (21.05％),Grade 4 were 8 weeks (3.83％),and Grade 5 were 0 week.Conclusion This classified evaluation system provided simple,comprehensive and comparable reference indicators and used for the evaluation on influenza epidemics,also providing suggestions for influenza prevention and control accordingly.