Electrochemical Synthesis of Copper Mesh-Supported Thermo-Catalysts.

Metallic substrates, widely studied in the context of monolithic catalysts, offer inherent advantages in heterogeneous catalysis due to their exceptional thermal conductivity and mechanical properties. However, synthesizing stable monolithic catalysts with metallic substrates in a well-controlled manner remains a significant challenge. Here, this work introduces a simple, cost-efficient method to fabricate robust Cu mesh-supported thermo-catalysts using a modified cycling chronopotentiometry approach, where the Cu mesh serves as a donor of Cu ions. In this method, the Cu mesh surface generates two distinct layers of CuO and Cu2 O. In this context, CuO acts as the active phase, accounting for the high CO oxidation activity of Cu mesh catalysts with T90 ≈ 120 °C. Additionally, these catalysts exhibit considerable potential in electrocatalysis, showcasing significant research and application value.

The whole-cell proteome shows the characteristics of macrolides-resistant Bordetella pertussis in China linked to the biofilm formation.

The macrolides-resistant Bordetella pertussis (MR-Bp) isolates in China evolved from the ptxP1/fhaB3 allele and rapidly became predominant, suggestive of an adaptive transmission ability. This was different from the global prevalent ptxP3 strains, in which MR-Bp was rarely reported. The study aimed to determine the underlying mechanism responsible for fitness and resistance in these two strains. We identify proteomic differences between ptxP1/fhaB3 and ptxP3/fhaB1 strains using tandem mass tag (TMT)-based proteomics. We then performed in-depth bioinformatic analysis to determine differentially expressed genes (DEGs), followed by gene ontology (GO), and protein-protein interaction (PPI) network analysis. Further parallel reaction monitoring (PRM) analysis confirmed the expression of four target proteins. Finally, the crystal violet method was used to determine biofilm-forming ability. The results showed that the main significantly different proteins between the two represent isolates were related to biofilm formation. Furthermore, we have confirmed that ptxP1/fhaB3 showed hyperbiofilm formation in comparison with ptxP3/fhaB1. It is suggested that the resistance and adaptability of ptxP1/fhaB3 strains may be related to the formation of biofilm through proteomics. In a word, we determined the significantly different proteins between the ptxP1/fhaB3 and ptxP3/fhaB1 strains through whole-cell proteome, which were related to biofilm formation.

Mediator complex subunit 8 is a prognostic biomarker in hepatocellular carcinoma.

BACKGROUND: Mediator complex subunit 8 (MED8) is known for its role in encoding a subunit of the mediator complex (MED), that is critical for transcription. MED8 is significantly expressed in various tumors and has been correlated with an unfavorable prognosis. Nevertheless, no relationships have been found between MED8 and the clinical characteristics of hepatocellular carcinoma (HCC). METHODS: To conduct an evaluation of correlations between clinicopathologic characteristics and MED8 expression, the logistic regression, Wilcoxon signed-rank test, and Kruskal-Wallis test were used. To perform analysis of factors contributing to prognosis, the Kaplan-Meier approach and the Cox regression analyses were used. A nomogram on the basis of a Cox multivariate analysis was employed to anticipate the influence of MED8 on patient prognosis. The receiver operating characteristic (ROC) curves were plotted and the areas under the curve (AUC) were calculated to assess the prognostic value of MED8. Both immune infiltration analysis and Gene Set Enrichment Analysis (GSEA) were applied to reveal significant enrichment differences among TCGA data. Quantitative RT-PCR (qRT-PCR) and western blotting were used to verify the difference in the expression of MED8 in normal and hepatocellular carcinoma cells. The immunohistochemical method was used to validate the MED8 expression in tumor and adjoining tissues of HCC patients. RESULTS: A univariate analysis showed that high MED8 expression predicts poor disease-specific survival (DSS) (HR: 2.57; 95% confidence interval (CI) 1.62, 4.07; P<0.001). Multivariate regression analysis showed that high MED8 (adjusted HR: 3.032 (1.817, 5.060); P<0.001) expression and M stage (adjusted HR=4.075 (1.179-14.091) for M1 vs. M0, P=0.026) served as prognostic indicators of unfavorable overall survival in an independent manner in patients with HCC. The C-index for the nomogram was 0.732 (95% CI: 0.698, 0.766) and the AUC of MED8 was 0.817 (95% CI: 0.778, 0.857). Functional analysis showed that the cell cycle checkpoints, p53 dependent G1-DNA damage response, mitotic G1-G1-S phases, and mitotic G2-G2-M phases, were significantly enriched in DEGs associated with MED8 expression. Th2 cells were positively correlated with MED8 expression. CONCLUSIONS: MED8 predicts poor prognosis in HCC, possibly through modulating the cell cycle and Th2 cells.

Clinical and Laboratory Characteristics of Childhood Brucellosis in High-Risk Area of Western China.

Childhood brucellosis presents various nonspecific clinical symptoms, and limited laboratory data exist for clinical diagnosis. A better understanding of these clinical and laboratory characteristics can avoid clinical misdiagnosis and mistreatment. In this case-series study, a total of 78 children with a confirmed diagnosis of brucellosis were evaluated retrospectively. We observed that the incidence rate was high in the first two quarters every year. The most common symptom was fever. Osteoarticular involvement was found in 44.87% of the patients. Laboratory tests showed that the values of erythrocyte sedimentation rate, C-reactive protein (CRP), hemoglobin, neutrophils (NEU), alanine aminotransferase (ALT), and ferritin in childhood brucellosis with osteoarticular involvement had significant differences than those without osteoarticular involvement or control group (P < 0.05). Childhood brucellosis without osteoarticular involvement is often accompanied by decreased NEU and increased CRP and ALT compared with that of the control group (P < 0.05). The Receiver Operating Curves analysis revealed that NEU, CRP, and ALT could be used as adjunct parameters in the differential diagnosis of childhood brucellosis. These data suggest that clinical and laboratory characteristics are essential for every clinician and may have a complementary role in diagnosing childhood brucellosis.

The global prevalence ptxP3 lineage of Bordetella pertussis was rare in young children with the co-purified aPV vaccination: a 5 years retrospective study.

BACKGROUND: The global prevalent ptxP3 strains varies from about 10% to about 50% of circulating B. pertussis population in different areas of China. METHODS: To investigate the difference of vaccination status between different genotypes in the circulating B. pertussis after 10 years of acellular pertussis vaccine (aPV) used in China. The nasopharyngeal swabs and isolates of B. pertussis from these patients were used to perform genotyping of antigen genes. We use antibiotic susceptibility test against erythromycin and sequencing methods for site 2047 of 23S rRNA to determine the resistance status. RESULTS: The ptxP1 allele with erythromycin resistant (ER) B. pertussis infection (total of 449 subjects) consisted of 84.70 to 96.70% from 2012 to 2016 in this study. Vaccinated with co-purified aPV was found in 133(133/403,33.0%), 1(1/9,11.1%) and 2(2/21,9.5%) in ptxP1/fhaB3-ER, ptxP1/fhaB2-ES and ptxP3/fhaB2-ES B. pertussis infected children each, which showed a significant difference (χ2 = 6.87, P = 0.032). CONCLUSIONS: The ptxP3-ES B. pertussis was rare while the ptxP1-ER B. pertussis was steadily increased in Xi'an, China from 2012 to 2016, where co-purified aPV was prevalent used. This pose a hypothesis that the co-purified aPV might protect against ptxP3 strains more efficient, which generated a rare chance for ptxP3 strains to be under the antibiotic pressure and further developed to be erythromycin resistance. A further cohort study and the mechanisms of the additional antigen proteins of co-purified aPV protected against B. pertussis should be consideration.

Genomic epidemiology of erythromycin-resistant Bordetella pertussis in China.

Macrolides such as erythromycin are the empirical treatment of Bordetella pertussis infections. China has experienced an increase in erythromycin-resistant B. pertussis isolates since they were first reported in 2013. Here, we undertook a genomic study on Chinese B. pertussis isolates from 2012 to 2015 to elucidate the origins and phylogenetic relationships of erythromycin-resistant B. pertussis isolates in China. A total of 167 Chinese B. pertussis isolates were used for antibiotic sensitivity testing and multiple locus variable-number tandem repeat (VNTR) analysis (MLVA). All except four isolates were erythromycin-resistant and of the four erythromycin-sensitive isolates, three were non-ptxP1. MLVA types (MT), MT55, MT104 and MT195 were the predominant types. Fifty of those isolates were used for whole genome sequencing and phylogenetic analysis. Genome sequencing and phylogenetic analysis revealed three independent erythromycin-resistant lineages and all resistant isolates carried a mutation in the 23S rRNA gene. A novel fhaB3 allele was found uniquely in Chinese ptxP1 isolates and these Chinese ptxP1-ptxA1-fhaB3 had a 5-fold higher mutation rate than the global ptxP1-ptxA1 B. pertussis population. Our results suggest that the evolution of Chinese B. pertussis is likely to be driven by selection pressure from both vaccination and antibiotics. The emergence of the new non-vaccine fhaB3 allele in Chinese B. pertussis population may be a result of selection from vaccination, whereas the expansion of ptxP1-fhaB3 lineages was most likely to be the result of selection pressure from antibiotics. Further monitoring of B. pertussis in China is required to better understand the evolution of the pathogen.

A gastroenteritis outbreak associated with drinking water in a college in northwest China.

An acute gastroenteritis outbreak occurred at a private college in June 2014 in northwest China. This outbreak involved two teachers and 629 students (range: 17-27 years, average 21.3 years). The main symptoms included non-bloody watery diarrhea, stomach ache, nausea, and vomiting, and the duration of illness ranged from 1 to 7 days. Eight of 18 water samples were disqualified. Thirty-four norovirus (NoV) RNA-positive samples were identified from 48 stool-related samples (genotyping results: 13 GII, 13 GI and 8 GI + GII mixture). Fourteen NoV samples were successfully characterized for genotype, including two GII.6, five GI.6, four GI.3, and three GI.1. Enteropathogenic Escherichia coli (EPEC) and enteroadherent Escherichia coli (EAEC) DNA was detected from patient stool specimens and water samples from well one; two EAEC strains and one EPEC strain were isolated from patient stool specimens. The risk ratios (RRs) associated with wells one and two were 1.66 and 1.49, respectively, and the RR associated with living in north dormitory building one was 2.59. The patients' epidemiological characteristics, symptoms, and duration of illness indicated that NoV-contaminated water might be the origin of this outbreak, and RR analysis suggested that the two wells were linked to the outbreak.

Pertussis Outbreak in a Primary School in China: Infection and Transmission of the Macrolide-resistant Bordetella pertussis.

BACKGROUND: A pertussis outbreak was studied in a primary school in Xi'an, China, in March 2016. The school consisted of 536 pupils 6-12 years of age who were divided into 12 classes of 6 grades (2 classes for each grade). The identified index case was an 11-year-old girl at class 2 of grade 5. METHODS: Interview was conducted and nasopharyngeal swabs were taken from all pupils (N = 94) in the 2 classes of grade 5. Nasopharyngeal swabs were tested by both culture and polymerase chain reaction (PCR). RESULTS: Four culture- and 17 PCR-positive cases were identified in 94 pupils. Infection rate was significantly higher in class 2 compared with that in class 1 [37.0% (17/46) vs. 14.6% (7/48), χ(2) = 4.26, P < 0.05]. All Bordetella pertussis isolates were macrolide-resistant, harbored prn1/ptxP1/fim3-1 as previously reported and belonged to multilocus variable tandem repeat analysis type MLVA 195. Of the 17 DNAs positive for diagnostic PCR, 12 were also positive for 23S ribosomal RNA PCR. All the 12 DNAs had the A2047G mutation of 23S rRNA gene of B. pertussis. CONCLUSIONS: This study described a pertussis outbreak caused by macrolide-resistant B. pertussis in a primary school and indicated that close contact of index case causes the bacterial transmission.

Ultrasensitive Detection of Porcine Epidemic Diarrhea Virus from Fecal Samples Using Functionalized Nanoparticles.

Porcine epidemic diarrhea virus (PEDV) is the main causative agent of porcine diarrhea, which has resulted in devastating damage to swine industry and become a perplexed global problem. PEDV infection causes lesions and clinical symptoms, and infected pigs often succumb to severe dehydration. If there is not a timely and effective method to control its infection, PEDV will spread rapidly across the whole swine farm. Therefore, preclinical identification of PEDV is of great significance for preventing the outbreak and spread of this disease. In this study, a functionalized nanoparticles-based PCR method (UNDP-PCR) specific for PEDV was developed through systematic optimization of functionalized magnetic beads and gold nanoparticles which were further used to specifically enrich viral RNA from the lysate of PEDV stool samples, forming a MMPs-RNA-AuNPs complex. Then, oligonucleotides specific for PEDV coated on AuNPs were eluted from the complex and were further amplified and characterized by PCR. The detection limitation of the established UNDP-PCR method for PEDV was 25 copies in per gram PEDV stool samples, which is 400-fold more sensitive than conventional RT-PCR for stool samples. The UNDP-PCR for PEDV exhibited reliable reproducibility and high specificity, no cross-reaction was observed with other porcine viruses. In 153 preclinical fecal samples, the positive detection rate of UNDP-PCR specific for PEDV (30.72%) was much higher than that of conventional RT-PCR (5.88%) and SYBR Green real-time RT-PCR. In a word, this study provided a RNA extraction and transcription free, rapid and economical method for preclinical PEDV infection, which showed higher sensitivity, specificity and reproducibility, and exhibited application potency for evaluating viral loads of preclinical samples.

p53 signaling modulation of cell cycle arrest and viral replication in porcine circovirus type 2 infection cells.

Porcine circovirus type 2 (PCV2) is a ubiquitous pathogen in the swine industry worldwide. Previous studies have shown that PCV2 infection induces host cell apoptosis through up-regulation of p53. To further identify the regulatory roles of p53 signaling in the process of PCV2 infection, we established p53 gene knockout PK15 cell lines using the genomic editor tool CRISPR/Cas9, and further investigated the roles of p53 in modulating the cell cycle and viral replication in this study. The results show that PCV2 infection induced obvious S phase accumulation in wild-type PK15 cells and a compromised S phase accumulation in the p53 gene mutation cells (813PK15 p53m/m ), but did not induce obvious S phase accumulation in the p53 gene knockout cells (148PK15 p53-/-) compared with the respective mock infection. PCV2 infection activated p53 signaling, up-regulated the expression of p21, Cyclin E, and down-regulated Cyclin A, CDK2. In p53 deficient cells, however, PCV2-induced changes in Cyclin A, CDK2, and Cyclin E were efficiently reversed to the basal levels. Detection of PCV2 replication showed decreased viral ORF1 genomic DNA in p53 deficient cells (148PK15 p533-/-) and p53 mutated cells (813PK15 p53m/m ) compared with p53 wild-type cells after different synchronization treatment. Furthermore, PCV2 viral genomic DNA and Cap protein levels were higher in the cells released from S phase synchronized cells than in the cells released from the G0/G1 phase or G2/M phase-synchronized, or asynchronous cells after 18 h post-infection. Taken together, this study demonstrates that PCV2 infection induces S phase accumulation to favor viral replication in host cells through activation of the p53 pathway.

Immortalization of porcine placental trophoblast cells through reconstitution of telomerase activity.

Placental trophoblast cells (PTCs) play a critical role in histotrophic nutrient absorption, gaseous exchange, endocrine activities, and barrier function between the maternal and fetal systems. Establishment of immortalized porcine PTCs will help us to investigate the potential effects of different viruses on porcine trophoblast. In the present study, primary porcine PTCs were isolated from healthy gilts at Day 30 to Day 50 of gestation through collagenase digestion, percoll gradient centrifugation, and anti-CD9 immunomagnetic negative selection. To provide stable and long lifespan cells, primary PTCs were transfected with human telomerase reverse transcriptase (hTERT) gene. One porcine placental trophoblast cell line, named as hTERT-PTCs, was chosen for characterization. Human telomerase reverse transcriptase-PTCs achieved an extended replicative lifespan without exhibiting any neoplastic transformation signs in vivo or in vitro. The morphologic and key physiological characteristics of the immortalized PTCs were similar to primary PTCs. The immortalized PTCs retained original cell polarity and normal karyotype, expressed trophoblast-specific marker cytokeratin 7 and E-cadherin but did not express vimentin and major histocompatibility complex class I antigens as well as primary PTCs. Human telomerase reverse transcriptase-PTCs secreted low levels of chorionic gonadotrophin ß-subunit and placental lactogen that were coincident with primary PTCs. Taken together, our results demonstrated that the porcine PTCs could be immortalized through reconstitution of telomerase activity. The immortalized PTCs maintained its original characteristics and can be used as a model cells line to study the pathologic changes of porcine placental trophoblast in viruses infectious diseases.

Ultrasensitive Detection of RNA and DNA Viruses Simultaneously Using Duplex UNDP-PCR Assay.

Mixed infection of multiple viruses is common in modern intensive pig rearing. However, there are no methods available to detect DNA and RNA viruses in the same reaction system in preclinical level. In this study, we aimed to develop a duplex ultrasensitive nanoparticle DNA probe-based PCR assay (duplex UNDP-PCR) that was able to simultaneously detect DNA and RNA viruses in the same reaction system. PCV2 and TGEV are selected as representatives of the two different types of viruses. PCV2 DNA and TGEV RNA were simultaneously released from the serum sample by boiling with lysis buffer, then magnetic beads and gold nanoparticles coated with single and/or duplex specific probes for TGEV and PCV2 were added to form a sandwich-like complex with nucleic acids released from viruses. After magnetic separation, DNA barcodes specific for PCV2 and TGEV were eluted using DTT and characterized by specific PCR assay for specific DNA barcodes subsequently. The duplex UNDP-PCR showed similar sensitivity as that of single UNDP-PCR and was able to detect 20 copies each of PCV2 and TGEV in the serum, showing approximately 250-fold more sensitivity than conventional duplex PCR/RT-PCR assays. No cross-reaction was observed with other viruses. The positive detection rate of single MMPs- and duplex MMPs-based duplex UNDP-PCR was identical, with 29.6% for PCV2, 9.3% for TGEV and 3.7% for PCV2 and TGEV mixed infection. This duplex UNDP-PCR assay could detect TGEV (RNA virus) and PCV2 (DNA virus) from large-scale serum samples simultaneously without the need for DNA/RNA extraction, purification and reverse transcription of RNA, and showed a significantly increased positive detection rate for PCV2 (29%) and TGEV (11.7%) preclinical infection than conventional duplex PCR/RT-PCR. Therefore, the established duplex UNDP-PCR is a rapid and economical detection method, exhibiting high sensitivity, specificity and reproducibility.

Direct Detection of Erythromycin-Resistant Bordetella pertussis in Clinical Specimens by PCR.

Resistance of Bordetella pertussis to erythromycin has been increasingly reported. We developed an allele-specific PCR method for rapid detection of erythromycin-resistant B. pertussis directly from nasopharyngeal (NP) swab samples submitted for diagnostic PCR. Based on the proven association of erythromycin resistance with the A2047G mutation in the 23S rRNA of B. pertussis, four primers, two of which were designed to be specific for either the wild-type or the mutant allele, were used in two different versions of the allele-specific PCR assay. The methods were verified with results obtained by PCR-based sequencing of 16 recent B. pertussis isolates and 100 NP swab samples submitted for diagnostic PCR. The detection limits of the two PCR assays ranged from 10 to 100 fg per reaction for both erythromycin-susceptible and -resistant B. pertussis. Two amplified fragments of each PCR, of 286 and 112 bp, respectively, were obtained from a mutant allele of the isolates and/or NP swab samples containing B. pertussis DNAs. For the wild-type allele, only a 286-bp fragment was visible when the allele-specific PCR assay 1 was performed. No amplification was found when a number of non-Bordetella bacterial pathogens and NP swab samples that did not contain the DNAs of B. pertussis were examined. This assay can serve as an alternative for PCR-based sequencing, especially for local laboratories in resource-poor countries.

[Recognizing the vaccination strategy of pertussis according to the family aggregation feature of transmission].

OBJECTIVE: To understand the age distribution of pertussis patients admitted in the children hospital and to analyze the source of infection as well as its transmission patterns. METHODS: Patients visiting to the Children Hospital and epidemiologically related cases during Feb. 2012 to Aug. 2013 were tested to confirm the diagnosis. Excel 2007 software was used to analyze the age distribution and clinical symptoms of clinic cases, the source of infection or subsequent cases. RESULTS: 165 out of 254 clinically suspicious pertussis cases and 38 out of the 54 epidemiologically related cases were confirmed of having pertussis infection. There were 138 (83.6%) cases under 1 year of age in the confirmed clinical cases and 36 (94.7%) cases older than 20 years of age among the confirmed epidemiologically related pertussis cases. All the confirmed epidemiologically related cases were misdiagnosed or missed for diagnosis. As the source of pertussis infection in confirmed clinical cases, parents played an imported role among 25 of the 32 cases. Transmission from infants and/or little children to adults were also observed in this study. CONCLUSION: Infants accounted for the most among the pertussis patients that visiting the clinics. Adults, being misdiagnosed or missed diagnosed, were the main sources of infection to infants. Epidemics of pertussis occurred under family aggregation. Further study was in need to develop the proper strategy for pertussis booster vaccination.

Cross reactivity of Neisseria meningitidis crgA diagnostic PCR primers with nontypeable haemophilus influenzae.

BACKGROUND: CrgA based PCR are usually used for diagnosis of Neisseria meningitidis while the crgA gene was observed in the genomes of Haemophilus influenzae. In this study, we aimed to evaluate whether the crgA primers routinely used in the diagnosis of N. meningitidis could cross react with H. influenzae isolates. METHODS: A diagnostic test study analysis of sixty-two H. influenzae isolates from oropharyngeal swabs of healthy individuals aged 9 to 11 years between 2011 and 2012, using commonly used crgA primers for diagnostic analysis of N. meningitidis. RESULTS: It revealed that 19.3% nontypable H. influenzae isolates were positive for the crgA gene. All the biotype IV H. influenzae isolates were crgA PCR positive. CONCLUSIONS: Our study has shown a significant finding of crgA gene especially in bitotype IV nontypable H. influenzae by N. meningitidis crgA diagnostic PCR primers. It is necessary to further evaluate the prevalence of the crgA gene in more non-typable H. influenzae strains, particularly invasive strains.

Analysis of an outbreak of hemorrhagic fever with renal syndrome in college students in Xi'an, China.

The aim of the present study was to analyze an outbreak of hemorrhagic fever with renal syndrome (HFRS), caused by a Hantavirus, in college students in the northern urban area of Xi'an in 2012. The outbreak affected six students and included two deaths. The epidemiological survey revealed that both of the deceased cases were misdiagnosed initially, and treatment was delayed. Furthermore, a higher rodent population density and lower HFRS vaccine coverage were observed in the affected area, which indicates a possible role in the outbreak. Rattus norvegicus (Rn) and Mus musculus (Mm) were the predominant host populations in the area. Genotyping revealed that all HVs from patients and rodents were Hantaan virus (HTNV). Sequence analysis of the S segments revealed that the HTNVs reported in this study had high similarity with strains reported in 2011 and 1985, but these viruses diverged from a strain isolated in 1984 and the HTNV prototype strain 76-118. Detection of anti-HV IgG and amplification of the S segment of HTNV from a non-natural HTNV reservoir indicates that further investigations by increased rodent trapping are necessary.

[Comparative studies on different methods for laboratory diagnosis of pertussis].

OBJECTIVE: To confirm the clinically suspected pertussis cases(<1 years old) through laboratory methods. METHODS: From December, 2011 to December, 2012, patients with clinically suspected pertussis from Xi'an Children's Hospital were sampled, with their nasopharyngeal swabs collected, blood samples cultured and pertussis toxin IgG detected by PCR. RESULTS: were analyzed, using SPSS 16.0 software. RESULTS: 100 out of the 148 cases were laboratorial confirmed. 3, 88 and 34 cases were positive, through culture, PCR or pertussis toxin IgG respectively. 22 cases were both PCR and pertussis toxin IgG positive. There were significant differences between the results of IS481 PCR, days from the onset of symptoms (P < 0.01) and results of PT-IgG with the days from onset of symptoms (P < 0.01). CONCLUSION: Since the sensitivity of culture on pertussis was low, diagnosis on the disease should be linked to the results from PCR, PT-IgG and the days from onset of symptoms.