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Data concerning the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in asymptomatic and paucisymptomatic patients are lacking. We report a 3-family cluster of infections involving asymptomatic and paucisymptomatic transmission. Eight of 15 (53%) members from 3 families were confirmed with SARS-CoV-2 infection. Of 8 patients, 3 were asymptomatic and 1 was paucisymptomatic. An asymptomatic mother transmitted the virus to her son, and a paucisymptomatic father transmitted the virus to his 3-month-old daughter. SARS-CoV-2 was detected in the environment of 1 household. The complete genomes of SARS-CoV-2 from the patients were > 99.9% identical and were clustered with other SARS-CoV-2 sequences reported from China and other countries.

MiRNAs regulate the expression of target genes in diverse cellular processes and hence play important roles in different physiological processes, yet little is known about the stomach microRNAome (miRNAome) of the Tibetan pig. The objective of this experiment was to investigate differentially expressed stomach miRNAs participating in digestion. Firstly, we isolated total RNA by Trizol reagent from three Tibetan and three Yorkshire purebred pigs stomach samples at 90-day-old. Secondly, a comprehensive analysis of Tibetan and Yorkshire pig stomach miRNAomes was performed by small RNA sequencing in the Illumina HiSeq 2000 system. Finally, SYBR Green Real-time RT-PCR was performed to validate the differentially expressed miRNAs. We identified 318 unique miRNAs, 260 were co-expressed in both libraries, 17 and 31 miRNAs were specifically expressed in Tibetan and Yorkshire pigs respectively. Fifty six differentially expressed miRNAs were identified by the identifying differentially expressed genes 6 (IDEG6). Kyoto encyclopedia of genes and genomes analysis revealed that some of the differentially expressed miRNAs were associated with protein and fat digestion. Two differentially expressed miRNAs (miR-214-3p and ssc-un39) participating in the digestion of lipid were identified. Additionally, qRT-PCR results suggested that a higher expression of miR-214-3p in the Tibetan pig stomach could lead to relatively lower expression of calcium-dependent phospholipase A2, which is an enzyme important for the digestion of glycerol phospholipid. This study has delineated the different stomach miRNAs expression patterns of Tibetan and Yorkshire pigs, which would help explain the regulatory mechanisms of miRNAs in digestion of Tibetan pigs, and contribute to utilize a the unique digestion merits of Tibetan pig in future porcine hybridization breeding.

Toll-like receptors (TLRs), an important family of pattern-recognition receptors, and antimicrobial peptides (AMPs) contribute to the first line of innate protection of mammals against microbes. To compare characteristics of innate immunity between Tibetan and Yorkshire pigs, we investigated the mRNA abundance of TLR genes (TLR1-TLR9) and two AMP-encoding genes (PBD-1 and PR-39) in thymus, spleen, blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes of the two breeds at ages of 6, 12 and 24 weeks using quantitative real-time PCR. Results showed that all mRNAs were detected in all tissues. Transcript levels of the major TLR genes of Tibetan pigs were significantly higher than those of Yorkshires in most tissues of the immune system, with a higher abundance of porcine (PBD-1) (beta-defensin-1) and PR-39 mRNA in lymphoid organs and tissues, especially blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes. Our data suggest that Tibetan pigs have stronger innate immunity for triggering local and/or systemic immune responses to eliminate infections with pathogenic microorganisms.

IL-15 cDNA of Tibetan pig was firstly cloned from its activated lymphocytes, and then was sub-cloned into VR1020 to construct recombinant VRTIL-15 plasmid to study the in vitro and in vivo biological effects on animal. The VRTIL-15 was entrapped with chitosan modified with PEG-PEI (CS-PEG-PEI) to transfect HEK293 cells for the preliminary study of its expression in eukaryotic cells. The total RNA of HEK293 cell was isolated in 48h, and the successful expression of IL-15 was detected by RT-PCR and the supernatant of HEK293 cells was found to stimulate significant proliferation of lymphoblasts of pig. Subsequently, VRTIL-15 packed with CS-PEG-PEI was utilized to intramuscularly inoculate Kunming female mice at the age of 21 days. Their bloods were collected before and after inoculation on 1, 2, 3, 4 and 5 weeks to detect the changes of innate and adaptive immunity of animals. The results were found that Th and Tc, specific antibody to FMD, IgG, IgG1, IgG2a content markedly increased in the blood of treated mice compared with the control group (P

This study aimed at assessing the role of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the control of pleural effusion (PE) and survival in patients with primary lung adenocarcinoma. The concentrations of the 3 cytokines were measured in PE from 79 lung adenocarcinoma patients with malignant pleural effusion (MPE) and 23 patients with tuberculosis. Data were correlated with the efficacy of MPE control and patient survival. The level of MCP-1 in PE was significantly higher in patients with lung adenocarcinoma than those with tuberculosis. By contrast, the levels of TNF-α and IL-6 were significantly lower in patients with lung adenocarcinoma than those with tuberculosis. An MCP-1 level greater than 3,187 pg/mL (which was used as a cutoff point) indicated failure to control MPE (odds ratio [OR]=2.82, 95% confidence interval [CI]=1.02–7.82, p=0.04). In multivariate analysis, MCP-1 was confirmed as an independent prognostic factor for progression-free survival (hazard ratio [HR]=2.02, 95% CI=1.24–3.30, p=0.01). The level of MCP-1 in PE appears to be a reliable surrogate marker for evaluating the therapeutic efficacy in the control of MPE and predicting survival in lung adenocarcinoma patients with MPE.

The recent pandemic influenza A (H1N1 2009) virus infection has caused acute lung injury in susceptible population resulting in high mortality in ICU patients. In this report, we observed the effect of pre-B cell colony-enhancing factor (PBEF) on the inflammation and apoptosis in H1N1-infected human pulmonary microvascular endothelial cells (HPMECs). We constructed an in vitro HPMEC monolayer model. The results showed that H1N1 2009 induced the increased expression of inflammatory cytokines (IL-6/IL-8/TNF-α/IP-10) and apoptosis factors (FasL/TRAIL) in infected HPMECs. However, PBEF silencing with siRNA inhibited the expression of some inflammatory cytokines and decreased the apoptosis mediated by FasL. We conclude that PBEF might be partially responsible for the localized inflammatory response to H1N1 2009 in the lung microvascular endothelium and the H1N1-induced endothelial cell apoptosis probably through the FasL-mediated pathway.

A novel shuffled pig IL-2 gene and immunostimulatory sequences containing 11 CpG motifs were subcloned into the eukaryotic expression plasmid VR1020 and VR1012, respectively designated as the recombinant VRIL2S and VR1C, then they were encapsulated in chitosan nanoparticles (CNP) prepared by ionotropic gelation method. Forty 21-day-old piglets were divided into four groups and intramuscularly injected respectively with 0.5 mg VRIL2S-CNP, VR1C-CNP, VR1020-CNP and CNP along with the rabbit-attenuated swine fever virus vaccines. The bloods were weekly collected from the piglets after vaccination to detect the changes of immunoglobulins, specific antibodies, interleukins, IFN-γ and immune cells. The results were found that in comparison with the control VR1020-CNP and CNP group, the content of immunoglobulins, specific antibodies, IL-2, IL-6, IL-4 and IFN-γ significantly increased in the sera from the treated VRIL2S-CNP and VR1C-CNP group (P

MicroRNAs (miRNAs) play an important role in the modulation of various metabolic processes in the liver, yet little is known about the liver microRNAome (miRNAome) of the Tibetan pig. Here we used the Yorkshire pig as a control to analyze the Tibetan pig-specific liver miRNAome, and for preliminary investigation of differentially expressed miRNAs participating in metabolism. A comprehensive analysis of Tibetan and Yorkshire pig liver miRNAomes by small RNA sequencing identified 362 unique miRNAs. Among these, 304 were co-expressed in both libraries, and 10 and 48 miRNAs were specifically expressed. Differential expression analysis of miRNAs, miRNA target prediction and KEGG analysis revealed that differentially expressed miRNAs were associated mainly with the metabolism of glucose, lipid and protein. Six differentially expressed miRNAs (miR-34a, miR-326, miR-1, miR-335, miR-185 and miR-378) participating in the metabolism of glucose and lipid were identified. Additionally, qPCR results revealed that a lower expression of miR-34a in Tibetan pig liver may promote gluconeogenesis by increasing the expression of Sirtuin type 1 (Sirt1); a lower expression of miR-1 in Tibetan pig liver may promote the synthesis and accumulation of lipid by increasing the expression of Liver X receptor α (LXRα); and a lower expression of miR-185 in Tibetan pig liver may promote the uptake of cholesterol from blood and secretion of bile by increasing the expression of the scavenger receptor class B type I (SR-BI). Our results provide new information and understanding of porcine miRNA profiles, which may help explain the regulatory mechanisms of miRNAs in the metabolic functions of Tibetan pig liver, and provide new biomarkers to assist in the development of Tibetan pig breeding characteristics.

To investigate the molecular subtypes of 73 strains of Yersinia enterocolitica biotype 1A isolated in Shandong province by PFGE, and thereby to analyze the relationship between PFGE typing and biological characteristics.Seventy-three strains of Yersinia enterocolitica biotype 1A were isolated from animal feces and meat products in Gaomi city and Wulian county in Shandong province from 2008 to 2009. Motility test, serum agglutination and virulent genes detection by PCR were used to learn the biological characteristics of the isolated strains. The molecular subtypes were determined by PFGE, whose relationships with motility, serotypes and virulent genotypes were also analyzed.Out of the 73 strains of Yersinia enterocolitica, 5 showed medium-active motility while the other 68 showed well-active motility. The dominated serotypes were O:5(17/73) and O:8(14/73), followed by O:9(5/73) and O:7, 8(1/73), and there was no O:3 serotype found. Meanwhile, 36 strains couldn't be serotyped. All the strains were negative with the gene ail, ystA, yadA and virF, yet the positive rate of ystB gene was 72.6% (53/73). The 73 strains of Yersinia enterocolitica isolated could be subtyped into 54 PFGE patterns (K6GN11SD0001-K6GN11SD0054), most of which only had 1 or 2 isolated strains, and no pattern was dominant. The strains in the same or similar cluster were from different hosts; each serotype and toxic genotype scattered in the clustering trees, without specific correlation with PFGE subtypes. 4 out of 5 strains, which showed medium-active motility, belonged to one branch, with the similarity coefficient at 80.9% - 100.0%; while all the toxic genotype belonged to type B.Biotype 1A Yersinia enterocolitica has many clones, whose PFGE types had relations with motility, but no relations with virulent genotype and host.

This meta-analysis evaluated the effect of noninvasive, positive pressure ventilation on severe, stable chronic obstructive pulmonary disease (COPD).PUBMED, CNKI, Wanfang, EMBASE and the Cochrane trials databases were searched. Randomized controlled trials of patients with severe, stable COPD and receiving noninvasive positive pressure ventilation, compared with sham ventilation or no ventilation, were reviewed. The mortality, physiological and health related parameters were pooled to yield odds ratio (OR), weighted mean differences or standardized mean differences (SMD), with 95% confidence interval (CI).Eight parallel and three crossover randomized controlled trials met the inclusion criteria. Pooled analysis for parallel, randomized controlled trials showed noninvasive positive pressure ventilation: (1) Did not affect the 12- or 24-month mortality (OR 0.82, 95%CI: 0.48 to 1.41); (2) Improved the arterial carbon dioxide tension (SMD -0.88, 95%CI: -1.43 to -0.34); (3) Did not improve forced expiratory volume in one second (SMD 0.20, 95%CI: -0.06 to 0.46), maximal inspiratory pressure (SMD 0.01, 95%CI: -0.28 to 0.29) or 6-minute walk distance (SMD 0.17, 95%CI: -0.16 to 0.50); (4) Subgroup analysis showed noninvasive positive pressure ventilation improved the arterial carbon dioxide tension in hypercapnic patients. Pooled analysis for crossover randomized controlled trials did not show improvement in arterial blood gas or forced expiratory volume in one second with noninvasive positive pressure ventilation.Noninvasive positive pressure ventilation improves the arterial carbon dioxide tension but does not improve the mortality, pulmonary function, or exercise tolerance and should be cautiously used in severe stable chronic obstructive pulmonary disease.

To observe the expressions of nerve growth factor (NGF) and its tyrosine kinase A (TrkA) receptor on alveolar macrophage in a rat model of chronic obstructive pulmonary disease (COPD).Forty healthy male SD rats were randomly divided into a control group and a COPD group. The COPD model was established by exposing the rats to cigarette smoke for 6 months, and lung function changes were measured. Lung histopathological changes were detected by HE staining. The expression of NGF protein in the supernatant of alveolar macrophage (AM) culture medium was detected by ELISA. Confocal microscopy was used to identify the separation and purification of AM from bronchoalveolar lavage fluid, and to detect semi-quantitatively the expression of TrkA receptor on AM. NGF and its TrkA receptor at the mRNA level were evaluated by real-time PCR. The differences among groups were calculated by one way ANOVA, and comparison between groups was made by t test.Significant decrease of pulmonary compliance [(0.15 ± 0.03) ml/cm H(2)O (1 cm H2O = 0.098 kPa)] and minute ventilation [(0.045 ± 0.004) L], and significant increase of airway resistance [(0.038 ± 0.004) cm H2O×L(-1)×s(-1)] were found in the COPD group compared with the control group [(0.42 ± 0.05) ml/cm H2O and (0.102 ± 0.010) L and (0.016 ± 0.002) cm H2O×L(-1)×s(-1), t = 9.46 - 12.99, respectively, all P0.01]. Alveolar wall thinning, alveolar septa breakdown, alveolar enlargement and emphysema were significant in the COPD rats. The expression of NGF protein in the supernatant of AM culture medium was enhanced in the COPD group [(3.79 ± 1.52) ng/L] compared with the controls [(0.94 ± 0.27) ng/L, t = 4.13, P0.05]. Mean fluorescence intensity of TrkA protein on AM in the COPD group (19.5 ± 1.5) was higher than that in the control group (11.2 ± 1.9, t = 7.95, P0.05). The expressions of NGF and TrkA at mRNA level in the COPD group (24.8 ± 6.0 and 9.0 ± 3.3) were increased compared with the control group (1.0 ± 0.2 and 1.0 ± 0.4, t = 8.48 and 5.16, all P0.05).The expressions of NGF and its TrkA receptor on AM in COPD group were increased, indicating that NGF and its TrkA receptor might be involved in the pathogenesis of COPD mediated by AM.

Background Nucleic acid detection by polymerase chain reaction (PCR) is emerging as a sensitive and rapid diagnostic tool. PCR assays on serum have the potential to be a practical diagnostic tool. However, PCR on bronchoalveolar lavage fluid (BALF) has not been well established. We performed a systematic review of published studies to evaluate the diagnostic accuracy of PCR assays on BALF for invasive aspergillosis (IA). Methods Relevant published studies were shortlisted to evaluate the quality of their methodologies. A bivariate regression approach was used to calculate pooled values of the method sensitivity, specificity, and positive and negative likelihood ratios. Hierarchical summary receiver operating characteristic curves were used to summarize overall performance. We calculated the post-test probability to evaluate clinical usefulness. Potential heterogeneity among studies was explored by subgroup analyses. Results Seventeen studies comprising 1191 at-risk patients were selected. The summary estimates of the BALF-PCR assay for proven and probable IA were as follows: sensitivity, 0.91 (95% confidence interval (CI), 0.79–0.96); specificity, 0.92 (95% CI, 0.87–0.96); positive likelihood ratio, 11.90 (95% CI, 6.80–20.80); and negative likelihood ratio, 0.10 (95% CI, 0.04–0.24). Subgroup analyses showed that the performance of the PCR assay was influenced by PCR assay methodology, primer design and the methods of cell wall disruption and DNA extraction. Conclusions PCR assay on BALF is highly accurate for diagnosing IA in immunocompromised patients and is likely to be a useful diagnostic tool. However, further efforts towards devising a standard protocol are needed to enable formal validation of BALF-PCR.

To assess the value of galactomannan (GM) double-direct sandwich enzyme-linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA).A search in MEDLINE, EMbase, OVID, CBMdisc and CHKD from Jan. 1991 to Dec. 2008 was conducted to collect all articles about diagnostic tests of serum GM detection. Then the methodological quality was assessed by QUADAS-items, sources of heterogeneity investigated, pooled effect quantities evaluated, and meta-analysis studies, SROC curves, and subgroup analysis performed.Thirty-six articles with a population of 4959 patients were included. The average prevalence of IA was 10%(532/4959). Our meta-analysis reported a median heterogeneity (I(2) = 48.6%, P0.05), with a pooled DOR value of 19.10 (95%CI 12.67 - 28.79), a pooled sensitivity of 0.66 (95%CI 0.61 - 0.70), a pooled specificity of 0.90 (95%CI 0.89 - 0.90), a pooled positive likelihood ratio of 5.48 (95%CI 4.27 - 7.02), a pooled negative likelihood ratio of 0.38 (95%CI 0.29 - 0.50), and an area under curve of SROC 0.88. The rate of underdiagnosis of serum GM detection was 34% (168/490) and the rate of misdiagnosis was 10% (466/4469). With a rise in the cut-off value the sensitivity of GM test decreased and specificity increased. Two consecutive positive tests decreased the sensitivity but increased the specificity. Age had no significant effect on the diagnosis by GM test. Both antifungal prophylaxis and antifungal therapy had no significant effect on sensitivity and specificity of GM test for IA diagnosis.Serum GM detection is an effective diagnostic tool for invasive aspergillosis in high-risk populations.

Hospital-acquired pneumonia (HAP) is among the most common of nosocomial infections and is associated with prolonged hospitalizations, increased medical expenses, and increased mortality (1, 2).…