[Population structure of food-borne Staphylococcus aureus in China].

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.

[Safety of an inactivated 2019-nCoV vaccine (Vero) in adults aged 60 years and older].

Objective: To analyze the safety of an inactivated 2019-nCoV vaccine (Vero cell) in adults aged 60 years and older. Methods: A randomized, double-blind, placebo-controlled clinical study was conducted in May 2020 The eligible residents aged 60 and above were recruited in Renqiu city, Hebei Province. A total of 422 subjects (phase Ⅰ/Ⅱ:72/350) were enrolled. Two doses of the trial vaccine or placebo were randomly administered according to a 0 and 28-day immunization schedule. Subjects were randomly divided into two groups in Phase Ⅰ. Within each group, participants received vaccine or placebo in a ratio of 2∶1. Subjects were randomly divided into four groups in phase Ⅱ to receive low-dose, medium-dose, high-dose vaccine and placebo, respectively, in a ratio of 2∶2∶2∶1. A combination of regular follow-up and active reporting was used to observe adverse reactions within 28 days after vaccination, and compare the incidence rate of adverse reactions in the trial and control groups. Results: 422 subjects were (66.45±4.70) years old, and 48.82% were male (206/422). There were 100, 124, 124 and 74 patients enrolled into the low-dose, medium-dose, high-dose vaccine groups and the placebo group, respectively. One person without the vaccination was removed, and 421 participants who received at least one dose of vaccine were included in the safety analysis. Within 28 days after the first or second dose, a total of 20.67% (87/421) subjects had adverse reactions (both solicitation and non-solicitation). About 76 patients suffered grade 1 adverse reactions [18.05% (76/421)] and 22 patients suffered grade 2 adverse reactions [5.23% (22/421)]. No grade 3 or above adverse reactions occurred. A total of 19.71% (83/421) subjects had solicited adverse reactions. The most common grade 1 adverse reaction was injection site pain, followed by fever and fatigue. The most common grade 2 adverse reactions were fever and fatigue, followed by muscle pain and injection site redness. A total of 2.61% (11/421) subjects had unsolicited adverse reactions. A total of 1.66% (7/421) subjects had serious adverse events after vaccination, and no serious vaccine-related adverse events were reported. Conclusions: The inactivated SARS-CoV-2 vaccine is safe for people aged 60 years and above.

Health behaviour practices and expectations for a local cancer survivorship programme: a cross-sectional study of survivors of childhood cancer in Hong Kong.

INTRODUCTION: Lifestyle choices may influence health outcomes in cancer survivors. This study of childhood cancer survivors in Hong Kong investigated factors associated with health-protective and health-damaging behaviours; it also examined expectations of a survivorship programme. METHODS: This cross-sectional study recruited survivors of childhood cancer ≥2 years after treatment. Survivors completed a structured questionnaire to report their health practices and the perceived values of survivorship programme components. Multivariable logistic regression analysis was conducted to identify factors associated with health behaviours. RESULTS: Two hundred survivors were recruited (mean age=23.4 ± 8.8 years; mean duration since treatment, 13.4 ± 7.6 years). Comparatively few survivors exercised ≥4 days/week (16.0%), used sun protection (18.0%), and had a balanced diet (38.5%). Furthermore, comparatively few survivors reported that they had not undergone any immunisation (24.5%) or were unsure (18.5%) about their immunisation history. Most adult survivors were never-drinkers (71.0%) and never-smokers (93.0%). Brain tumour survivors were more likely to have unhealthy eating habits, compared with haematological malignancy survivors (odds ratio [OR]=2.45; 95% confidence interval [CI]=1.29-4.68). Lower socioeconomic status was associated with inadequate sun protection (OR=0.20; 95% CI=0.05-0.83), smoking (OR=5.13; 95% CI=1.48-17.75), and exposure to second-hand smoke (OR=3.52; 95% CI=1.42-8.69). Late-effects screening (78.5%) and psychosocial services to address psychological distress (77%) were considered essential components of a survivorship programme. CONCLUSIONS: Despite the low prevalences of health-damaging behaviours, local survivors of childhood cancer are not engaging in health-protective behaviours. A multidisciplinary programme addressing late effects and psychosocial aspects may address the multifaceted needs of this special population.

[Application of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients].

Objective: To investigate the diagnostic efficacy and potential application value of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients. Methods: A total of 403 patients, including 254 males and 149 females aged from 16 to 100 (50±19) years, who received emergency treatment for trauma and chest CT examination in the Eastern Theater General Hospital from September 2019 to November 2019 were retrospectively analyzed. Dr. Wise Lung Analyzer's chest CT auxiliary diagnosis system was applied to detect 5 types of injuries, including pneumothorax, pleural effusion/hemothorax, pulmonary contusion (shown as consolidation and ground glass opacity), rib fractures, and other fractures (including thoracic vertebrae, sternum, scapula and clavicle, etc.) and 6 other abnormalities (bullae, emphysema, pulmonary nodules, stripe, reticulation, pleural thickening). The diagnostic reference standards were labeled by two radiologists independently. The sensitivity and specificity of the auxiliary diagnosis system were evaluated. The imaging diagnostic reports were compared with the results of the auxiliary diagnosis system, and the diagnostic consistency between the two was calculated by using the Kappa test. Results: According to the reference standards, among the 403 patients, 29 were pneumothorax, 75 were pleural effusion/hemothorax, 131 were pulmonary contusion, 124 were rib fractures, and 63 were other fractures. The sensitivity and specificity of the auxiliary diagnosis system for detection of pneumothorax, pleural effusion/hemothorax, rib fractures, and other fractures were 96.6%, 97.6%, 80.0%, 99.7%, 99.2%, 83.9%, 84.1%, and 99.7%, respectively. The sensitivity of detecting lung contusion was 97.7%. There was a high consistency between the auxiliary diagnosis system and imaging diagnosis in the diagnosis of injuries, in which the kappa values of pneumothorax, pleural effusion, rib fracture and other fractures were 0.783, 0.821, 0.706 and 0.813, respectively (all P<0.001). Two cases of pneumothorax, three cases of pleural effusion/hemothorax, nine cases of rib fractures, and six cases of other fractures missed by imaging diagnosis were all detected by the auxiliary diagnosis system. The detection sensitivity of the auxiliary diagnosis system was higher for emphysema, pulmonary nodules and stripe (all>85%), but lower for bullae, reticulation and pleural thickening. Conclusions: The deep learning-based chest CT auxiliary diagnosis system could effectively assist chest CT to detect injuries in emergency trauma patients, which was expected to optimize the clinical workflow.

[The effect of booster dose vaccination 21- to 32-years after primary vaccination with hepatitis B vaccine in the population born from 1986 to 1996 in Zhengding County of Hebei Province].

Objective: Aanalysis the effect of booster one dose of hepatitis B vaccine after 21-32 years of primary immunization in Zhengding Country of Hebei Province. Methods: A total of 322 participants who were born between 1986 and 1996, received a full course of primary vaccination with plasma-derived hepatitis B vaccine (HepB), had no experience with booster vaccination, were HBsAg, anti-HBcnegative, had anti-HBs<10 mIU/ml, completed the booster and had laboratory results were enrolled between August 2017 to February 2018. A simple random method was uesd to randomly assigned 322 subjects to two groups, receiving a booster dose of HepB derived from either Saccharomyces cerevisiae ï¼»HepB (SC), (151 cases)ï¼½ or Chinese hamster ovary-derived HepB ï¼»HepB (CHO), (171 cases)ï¼½, the dose was 20 µg. Blood samples were collected 30 days after boosting and quantitatively tested for the geometric mean concentration (GMC) of anti-HBs to assess immunological effect. The related influencing factors of GMC and seroconversion rates of anti-HBs were analyzed by multiple linear regression and multivariate logistic regression models. Results: The 266 subjects (82.61%) had anti-HBs≥ 10 mIU/ml, and GMC was (131.63±12.94) mIU/ml.The seroconversion rates of anti-HBs in the anti-HBs<2.5 mIU/ml group and 2.5-10 mIU/ml group were 74.54% (161 cases) and 99.06% (105 cases), respectively (P<0.001).The seroconversion rates of anti-HBs after one dose of HepB (CHO) was higher than that of one dose of HepB (SC), the seroconversion rates were 87.13% (149 cases) and 77.48% (117 cases), respectively (P=0.023). Participants boostered with HepB (CHO) was the factor influencing the effect of strengthening immunization compared with boostered with HepB (SC), and OR (95%CI) was 1.91 (1.02-3.56) (P=0.042).Compared with anti-HBs<2.5 mIU/ml, prebooster anti-HBs was between 2.5 mIU/ml and 10 mIU/ml was the related factor of seroconversion rates of anti-HBs after booster immunization, and OR (95%CI) was 36.15 (4.91-266.02) (P<0.001). Conclusion: Participants boostered withone dose of HepB had a good immune response. Pre-booster anti-HBs concentration and a variety of vaccine were related factors of immune response.

Arresting of miR-186 and releasing of H19 by DDX43 facilitate tumorigenesis and CML progression.

Cancer-testis (CT) antigens, rarely in normal tissues except testis, are expressed in many tumor types. In recent years, DDX43 has been shown to be expressed in several malignancies. However, the role of DDX43 during tumorigenesis is not well established. In the present study, we explored the function of DDX43 in chronic myeloid leukemia (CML). We found that DDX43 overexpression in CML cell lines enhanced survival and colony formation, inhibited cell apoptosis, promoted tumorigenesis, and CML progression. In contrast, silencing of DDX43 inhibited cell survival and tumorigenesis. Upregulated H19 and downregulated miR-186 were identified in DDX43-transfected cells. Furthermore, we demonstrated that miR-186 targeted DDX43, and overexpressed miR-186 increased apoptosis and decreased cell survival. We also showed that DDX43 regulated the expression of H19 through demethylation and silencing H19 inhibited cell survival. Taken together, these results indicate that DDX43 provides critical support to the progression of CML by enhancing cell survival, colony formation, and inhibiting cell apoptosis, thereby implicating DDX43 as a potential therapeutic target in CML.

Biological and ecological evidences suggest Stipa krylovii (Pooideae), contributes to optimal growth performance and population distribution of the grasshopper Oedaleus asiaticus.

Oedaleus asiaticus Bey. Bienko is a significant grasshopper pest species occurring in north Asian grasslands. Outbreaks often result in significant loss in grasses and economic losses. Interestingly, we found this grasshopper was mainly restricted to Stipa-dominated grassland. We suspected this may be related to the dominant grasses species, Stipa krylovii Roshev, and hypothesized that S. krylovii contributes to optimal growth performance and population distribution of O. asiaticus. A 4 year investigation showed that O. asiaticus density was positively correlated to the above-ground biomass of S. krylovii and O. asiaticus growth performance variables (survival rate, size, growth rate) were significantly higher in Stipa-dominated grassland. A feeding trial also showed that O. asiaticus had a higher growth performance when feeding exclusively on S. krylovii. In addition, the choice, consumption and the efficiency of conversion of ingested food (ECI) by O. asiaticus was highest for S. krylovii compared with other plant species found in the Asian grasslands. These ecological and biological traits revealed why O. asiaticus is strongly associated with Stipa-dominated grasslands. We concluded that the existence of S. krylovii benefited the growth performance and explained the distribution of O. asiaticus. These results are useful for improved pest management strategies and developing guidelines for the monitoring of grasshopper population dynamics against the background of vegetation succession and changing plant communities in response to activities such as grazing, fire and climate change.

[Progress of study on changes of mitochondrial and its role in obstructive sleep apnea hypopnea syndrome].

Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common respiratory disease which has become an important public health problem. A high prevalence of OSAHS in the elderly may suggest that aging could be considered as a risk factor for the development of OSAHS. Recent work that has advanced understanding of mutations accumulating over time in the mitochondrial DNA (mtDNA) has been closely associated with aging. More and more researchers pay attention to changes of mitochondria morphology, electron transport chain enzymes and mtDNA. The process research of accumulation of circular mtDNA bearing deletions or mtDNA with accumulated point mutations in OSAHS subjects might be able to make mitochondrial become a representative biomarker for adverse outcomes from oxidative stress and cardiovascular diseases in the future.

Cardiac over-expression of microRNA-1 induces impairment of cognition in mice.

Large cohort studies have revealed a close relationship between cognitive impairment and cardiovascular diseases, although the mechanism underlying this relationship remains incompletely understood. In this study, using a transgenic (Tg) mouse model of cardiac-specific over-expression of microRNA-1-2 (miR-1-2), we observed that microRNA-1 (miR-1) levels were increased not only in the heart but also in the hippocampus and blood, whereas its levels did not change in the skeletal muscle of Tg mice compared with age-matched wild-type (WT) mice. Six-month-old Tg mice showed cognitive impairment compared with age-matched WT mice, as assessed using the Morris Water Maze test. The brain-derived neurotrophic factor (BDNF) level and cyclic AMP-responsive element-binding protein (CREB) phosphorylation were also significantly reduced in the hippocampi of the Tg mice, as evaluated by Western blot. Further examination showed that BDNF protein expression was down- or up-regulated by miR-1 over-expression or inhibition, respectively, and was unchanged by binding site mutations or miRNA-masks for the 3'UTR of Bdnf, indicating that this gene is a potential target of miR-1. Knockdown of miR-1 by hippocampal stereotaxic injection of an anti-miR-1 oligonucleotide fragment carried by a lentivirus vector (lenti-pre-AMO-miR-1) led to up-regulation of BDNF expression and prevented the reduction in cognitive performance in the Tg mice without affecting cardiac function. Our findings demonstrate that cardiac over-expression of miR-1 also induces behavioral abnormalities that may be associated, at least in part, with the down-regulation of BDNF expression in the hippocampus. This study definitely contributes to the understanding of the relationship between cardiovascular disease and cognitive impairment.

Should ascitis volume and anthropometric measurements be estimated in hospitalized alcoholic cirrotics?

INTRODUCTION: Ascitis and undernutrition are frequent complications of cirrhosis, however ascitis volume and anthropometric assessment are not routinely documented or considered in prognostic evaluation. In a homogeneous cohort followed during two years these variables were scrutinized, aiming to ascertain relevance for longterm outcome. METHODS: Population (N = 25, all males with alcoholic cirrhosis) was recruited among patients hospitalized for uncomplicated ascitis. Exclusion criteria were refractory or tense ascitis, cancer, spontaneous bacterial peritonitis, bleeding varices and critical illness. Measurements included ultrasonographically estimated ascitis volume, dry body mass index/BMI , upper arm anthropometrics, hematologic counts and liver function tests. RESULTS: Population (age 48.3 ± 11.3 years, BMI 21.1 ± 3.5 kg/m², serum albumin 2.5 ± 0.8 g/dL) was mostly in the Child-Pugh C category (77.8%) but clinically stable. During the follow-up period of 22.6 ± 3.8 months, additional hospitalizations numbered 1.7 ± 1.0 and more than one quarter succumbed. Admission ascitis volume corresponded to 7.1 ± 3.6 L and dry BMI to 18.3 ± 3.5 kg/m². Child Pugh index was relevant for both mortality and rehospitalization. Nevertheless, similar matches for mortality were documented with ascitis volume and dry BMI, and arm circumference below the 5th percentile was highly significantly associated with rehospitalization. CONCLUSIONS: A greater association than hitherto acknowledged, between ascitis volume and anthropometric measurements from one side, and long-term rehospitalization and mortality from the other, was demonstrated in male stable alcoholic cirrhotics. Further studies with alcoholic and other modalities of cirrhosis including women are recommended.

Activation of neurons in cardiovascular areas of cat brain stem affects spinal reflexes.

In 65 cats anesthetized with chloralose (40 mg/kg) and urethane (400 mg/kg), the effects of electrical stimulation and microinjection of sodium glutamate (0.25 M, 100-200 nl) in the pressor areas in the rostral brain stem on the evoked L5 ventral root response (EVRR) due to intermittent stimulation of sciatic afferents were compared to stimulating the dorsomedial (DM) and ventrolateral (VLM) medulla. In general, stimulating these rostral brain stem pressor areas including the diencephalon (DIC) and rostral pons (RP) produced increases in systemic arterial pressure (SAP). In most of the cases (85%) there were associated changes in the EVRR, predominantly a decrease in EVRR (72%). Stimulation of the midbrain (MB, principally in the periaqueductal grey) produced decreases in SAP and EVRR. Decreases in EVRR was observed in 91% of the DM and VLM stimulations in which an increase in SAP was produced. This EVRR inhibition was essentially unaltered after acute midcollicular decerebration. Increases in EVRR were also observed and occurred more often in the rostral brain stem than in the medulla. Since changes of both EVRR and SAP could be reproduced by microinjection of Glu into the cardiovascular-reactive areas of the brain stem, this suggests that neuronal perikarya in these areas are responsible for both actions. On some occasions, Glu induced changes in EVRR but not in SAP. This effect occurred more frequently in the rostral brain stem than in the medulla. The present data suggest that separate neuron population exist in the brain stem for the integration of SAP and spinal reflexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased plasma endothelin-1 concentration in patients with acute cerebral infarction and actions of endothelin-1 on pial arterioles of rat.

In acute cerebral ischemia there are severe damages of endothelium which have been recognized as the stimuli to secrete endothelin-1, an endothelium-derived peptide and the most potent vasoconstrictor ever known. This study was to measure plasma endothelin-1 level in patients with cerebral infarction and explore the relationship between endothelin-1 and ischemic stroke. The possible involvement of endothelin-1 in local regulation of cerebral arterioles was also investigated. Plasma levels of endothelin-1 were measured by radioimmunoassay in 21 patients. Using a micro-video system, the endothelin-1 actions were also observed on rat pial arterioles in vivo, and with incomplete cerebral ischemia model (rat), effect of ischemia affects the endothelin-1 action. There was a marked increase in plasma endothelin-1 level in the patients and the elevation persisted during the acute and subacute period of stroke. There was a positive correlation between the peptide concentration and infarct size (r = 0.655, P < 0.01). In rats, endothelin-1 (dose range: 10(-10) mole/L-10(-7) mole/L) induced a dose-dependent arteriole contraction after subdural administration. Arteriole calibers were decreased by 27.7% +/- 3.8% (10(-9) mole/L), 46.8% +/- 4.9% (10(-8) mole/L) and 78.5% +/- 4.7% (10(-7) mole/L), respectively. Cerebral ischemia significantly enhanced the action of endothelin-1 (96.4% +/- 7.2% vs 58.2% +/- 6.8%). Endothelin-1 plays an important role in regulating local circulation of ischemic brain. The notable and lasting increase in plasma level of endothelin-1 are associated with cerebral ischemia and infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence that rifampicin can stimulate readthrough of transcriptional terminators in Escherichia coli, including the attenuator of the rpoBC operon.

The genes encoding the beta and beta' subunits of RNA polymerase in E.coli, rpoB and rpoC, lie downstream of at least two ribosomal protein genes, rplJ (encoding L10) and rplL (L7/12), in a common operon. All four genes are served by promoter PL10, and an attenuator (partial terminator) of transcription, t1, lies between rplJL and rpoBC. Treatment of E.coli with rifampicin, under conditions producing partial inhibition of general RNA synthesis, can stimulate transcription of rpoBC. We have investigated the locus of this effect by fusing PL10 and t1 separately to galK, in suitable plasmids. Our studies of these fusions, and similar fusions involving transcriptional terminators derived from coliphage T7, indicate that low concentrations of rifampicin cause increased readthrough of several different transcriptional terminators in E.coli in vivo, including rpo t1. We discuss whether or not this unspecific mechanism is solely responsible for the observed stimulatory effects of the drug on rpoBC transcription.

Internal promoters of the rpoBC operon of Escherichia coli.

Four ribosomal protein genes, rplA, rplJ, rplK and rplL form an operon in E. coli together with the genes rpoB and rpoC which encode the beta and beta' subunits of RNA polymerase. Transcription is initiated principally at two promoters, PL11 and Pl, the overall structure of the operon being (in the direction of transcription) PL11 rplK rplA Pl rplJ rplL rpoB rpoC. Here we describe studies of phage lambda derivatives carrying various segments of this operon, which demonstrate the existence of at least three additional weak internal promoters, and help to define their positions and strengths.

The haemostatic effects of the Chinese herbal drug Yunnan Bai Yao: a pilot study.

The effects of Yunnan Bai Yao on the bleeding time in rats and the blood clotting time in rabbits and man were studied. The medicinal preparation markedly shortened both the bleeding and clotting times; the decreases were significantly more intense than those inconsistently produced by starch or by starch with calcium. These preliminary findings suggest that the action of Yunnan Bai Yao appears not to be due to its pH (5.2) or to vasoconstriction, but other factors such as its calcium content or the physical effect of its particle size cannot yet be excluded.