Serotypes and Genotypes of Streptococcus pneumoniae in an Unvaccinated Population in Suzhou, China.

Background: Streptococcus pneumoniae is a significant etiological agent of infection and commonly inhabits the human nasopharynx, alongside other potentially pathogenic bacteria. In this study, S. pneumoniae strains were obtained from a community population and subjected to investigation of their phenotypes, genotypes, and vaccine coverage. Methods: S. pneumoniae was isolated from nasopharyngeal swab samples of a healthy population in the Guangfu Community. Capsular serotypes and genotypes were identified using Quellung reaction and multilocus sequence typing (MLST), respectively. The antimicrobial susceptibility was tested using minimum inhibitory concentrations. Results: In total, 500 unvaccinated people were sampled. Ninety-four S. pneumoniae strains were identified. Common serotypes were 19F, 6A, and 9V. The strain coverages of PCV13 and PPV23 were 61.7% and 58.5%, respectively. About 27.6% isolates were non-susceptible to penicillin, and over 80% were resistant to erythromycin and doxycycline. Among 27 novel sequence types (STs) identified in all strains, the most common STs were ST236 (6/94, 6.4%) and ST12669 (6/94, 6.4%). Nearly half of the strains were grouped into four clone complexes (CC12665, CC271, CC6011, and CC180), of which CC271 showed the highest resistance to PEN. Conclusion: In our study, various drug-resistant clone complexes of Streptococcus pneumoniae were found in the healthy population, the elderly, and children. Consequently, pneumococcal vaccines should be included in the national immunization schedule to prevent disease spread.

Pec 1 of Pseudomonas aeruginosa Inhibits Bacterial Clearance of Host by Blocking Autophagy in Macrophages.

Pseudomonas aeruginosa (P. aeruginosa), a common opportunistic pathogen, is highly prone to chronic infection and is almost impossible to eradicate, especially attributed to virulence factors and adaptive mutations. In the present study, pseudomonas effector candidate 1 (Pec 1), a novel virulence factor of P. aeruginosa, was investigated, which inhibited bacterial clearance by the host and aggravated lung injury. Further, it demonstrated that Pec 1 inhibited miR-155 via suppressing integrin ß3 expression, thereby activating PI3K-AKT-mTOR and inhibiting autophagy in macrophages. Additionally, the identification of Pec 1 in sputum was related to the bacterial load and assisted in rapid diagnosis of P. aeruginosa infection. This finding underlined the importance of Pec 1 in the pathogenesis of P. aeruginosa infection and indicated that Pec 1 could be a vital independent virulence factor during chronic infection with P. aeruginosa, providing new insights in rapid diagnosis, therapeutic targets, and vaccine antigens of P. aeruginosa infection.

Emergence of Rarely Reported Extensively Drug-Resistant Salmonella Enterica Serovar Paratyphi B among Patients in East China.

BACKGROUND: In recent years, global concern over increasing multidrug resistance (MDR) among various Salmonella serotypes has grown significantly. However, reports on MDR Salmonella Paratyphi B remain scarce, let alone the extensively drug-resistant (XDR) strains. METHODS: In this retrospective study, we investigated the isolates of Salmonella Paratyphi B in Jiangsu Province over the past decade and carried out antimicrobial susceptibility tests, then the strains were sequenced and bioinformatics analyses were performed. RESULTS: 27 Salmonella Paratyphi B strains were identified, of which the predominant STs were ST42 (11), ST86 (10), and ST2814 (5). Among these strains, we uncovered four concerning XDR Salmonella Paratyphi B ST2814 strains (4/5) which were previously unreported. These alarmingly resistant isolates showed resistance to all three major antibiotic classes for Salmonella treatment and even the last resort treatment tigecycline. Bioinformatics analysis revealed high similarity between the plasmids harbored by these XDR strains and diverse Salmonella serotypes and Escherichia coli from China and neighboring regions. Notably, these four plasmids carried the ramAp gene responsible for multiple antibiotic resistance by regulating the AcrAB-TolC pump, predominantly originating from China. Additionally, a distinct MDR ST42(1/11) strain with an ICE on chromosome was also identified. Furthermore, phylogenetic analysis of global ST42/ST2814 isolates highlighted the regional specificity of these strains, with Jiangsu isolates clustering together with domestic isolates and XDR ST2814 forming a distinct branch, suggesting adaptation to local antibiotic pressures. CONCLUSIONS: This research underscores the pressing need for closely monitoring the MDR/XDR Salmonella Paratyphi B, particularly the emerging ST2814 strains in Jiangsu Province, to effectively curb its spread and protect public health. Moreover, surveillance should be strengthened across different ecological niches and genera to track resistance genes and horizontal gene transfer elements under the concept of "ONE HEALTH".

Comprehensive quality evaluation of different types of Gardeniae Fructus (Zhizi) and Shuizhizi based on LC-MS/MS.

Gardeniae Fructus (Zhizi) serves as both a medicinal and edible substance and finds widespread use in various industries. There are often two kinds of medicinal materials in the market: Zhizi and Shuizhizi. Typically, Zhizi with small, round fruit is used for medicinal purposes, while Shuizhizi, characterized by large, elongated fruit, is employed for dyeing. Market surveys have revealed a diverse range of Zhizi types, and modern research indicates that Shuizhizi contains rich chemical components and pharmacological activities. In this study, we collected 25 batches of Zhizi and Shuizhizi samples, categorizing them based on appearance into obovate and round fruits, with seven length grades (A-G). Using the ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS) method, we simultaneously quantified 13 main chemical components in fruits of Gardenia species. In addition, we compared the weight percentage of the pericarp, flesh, and seeds parts of samples with different traits, and quantified 13 chemical components in different parts. Results indicated that, aside from a few instances of overlapping fruit size ranges, Shuizhizi generally exhibits larger and longer dimensions than Zhizi. The weight proportion of the Shuizhizi pericarp is often higher than that of the Zhizi pericarp. Quantitative results highlighted significant differences in the chemical component content between Zhizi and Shuizhizi, with Shuizhizi generally containing higher levels of iridoids. The PCA and OPLS-DA analysis distinctly divided Shuizhizi and Zhizi, among which three iridoids, two organic acids, and one flavonoid made significant contributions to their classification. Cluster heatmap analysis also demonstrated complete separation between Zhizi and Shuizhizi, with clear distinctions among Zhizi samples from different origins. The distribution of the 13 chemical components in different Zhizi and Shuizhizi parts remained consistent, with iridoids and pigments concentrated in the seeds and flesh, and two organic acids and one flavonoid enriched in the pericarp. In summary, this study contributes valuable insights for classifying Zhizi and offers guidance on the rational use of Shuizhizi and the different parts of Zhizi.

Carbon Trading in China Reduces the Dependence of Household Waste Electrical and Electronic Equipment Recycling on Government Subsidies.

China's enterprises of waste electrical and electronic equipment (WEEE) recycling suffer from low profitability that is highly dependent on government subsidies. This low economic gain impedes the sustainable growth of China's WEEE-recycling sector and also adds to the government's financial burden. Prior life-cycle studies have approved the carbon reduction potentials or net carbon credit of recycling WEEE. However, policymakers fail to know whether the revenue from selling carbon credits can offset the government's financial subsidy. We performed life-cycle and cost-benefit analyses for a case recycling enterprise that processes six categories of household appliances. The results show that the reduction potentials of greenhouse gases range from 930-3450 kgCO2e by recycling per ton of household appliances and materials substitution. The recycling enterprise would gain extra revenue ranging from 32 to 160 RMB per ton of appliance if the carbon credits were sold at China's current carbon price, i.e., 45-60 RMB tCO2e-1. Recycling waste refrigerators exhibits the highest carbon revenue, offsetting 6-17% of the government's financial subsidy. Microcomputers, by contrast, indicate the lowest carbon revenue, equivalent to 1-3% of its highest government subsidy. For each household appliance category, when the carbon price reaches 270-600 RMB tCO2e-1, selling carbon credits can fully offset the government's financial subsidy. Constrained by the processing capacity of the case enterprise, optimizations for appliance-recycling composition contribute a 15-25% profit growth to the current economic gains. Interpreting the specific profit depends on the predefined scenarios of carbon price and the substitution rate of the regenerated materials for the virginal ones. Our findings show that raising the profitability of WEEE recycling enterprises through the carbon trading policy contributes to the sustainable growth of China's WEEE-recycling sector while alleviating the government's financial burden.

Carbapenem-resistant gram-negative bacterial prevention practice in nosocomial infection and molecular epidemiological characteristics in a pediatric intensive care unit.

Introduction: The increasing prevalence of carbapenem-resistant gram-negative bacilli infection has emerged as a substantial threat to human health. Methodology: In January 2017, a screening program for carbapenem-resistant gram-negative bacilli colonization was performed in a pediatric intensive care unit (PICU). Subsequently, different strategies for carbapenem-resistant gram-negative bacilli cohorting and patient placements were introduced in January 2018. Results: The increase in the single room isolation (type A) and the resettlement of the same area placement (type B) resulted in a significant decrease in the nosocomial infection rate from 2.57% (50/1945) in 2017 to 0.87% (15/1720) in 2021 (P < 0.001). Notably, the incidence of nosocomial carbapenem-resistant gram-negative bacilli infections decreased in 2019 (P = 0.046) and 2020 (P = 0.041) compared with that in the respective previous year. During 2019 and 2020, a statistically significant increasing trend of type A and type B placements was observed (P < 0.05, each), which may have contributed to the decline of carbapenem-resistant gram-negative bacilli infection. The primary carbapenemase genes identified in carbapenem-resistant isolates of Klebsiella pneumoniae and Acinetobacter baumannii were blaKPC-2 from sequence type 11 and blaOXA-23 from sequence type 1712. Conclusion: The integration of various placements for patients with carbapenem-resistant gram-negative bacilli infection with active screening has been demonstrated as an effective preventive strategy in the management of carbapenem-resistant gram-negative bacilli infection.

Gapless Genome Assembly of Puccinia triticina Provides Insights into Chromosome Evolution in Pucciniales.

Chromosome evolution drives species evolution, speciation, and adaptive radiation. Accurate genome assembly is crucial to understanding chromosome evolution of species, such as dikaryotic fungi. Rust fungi (Pucciniales) in dikaryons represent the largest group of plant pathogens, but the evolutionary process of adaptive radiation in Pucciniales remains poorly understood. Here, we report a gapless genome for the wheat leaf rust fungus Puccinia triticina determined using PacBio high-fidelity (HiFi) sequencing. This gapless assembly contains two sets of chromosomes, showing that one contig represents one chromosome. Comparisons of homologous chromosomes between the phased haplotypes revealed that highly frequent small-scale sequence divergence shapes haplotypic variation. Genome analyses of Puccinia triticina along with other rusts revealed that recent transposable element bursts and extensive segmental gene duplications synergistically highlight the evolution of chromosome structures. Comparative analysis of chromosomes indicated that frequent chromosomal rearrangements may act as a major contributor to rapid radiation of Pucciniales. This study presents the first gapless, phased assembly for a dikaryotic rust fungus and provides insights into adaptive evolution and species radiation in Pucciniales. IMPORTANCE Rust fungi (Pucciniales) are the largest group of plant pathogens. Adaptive radiation is a predominant feature in Pucciniales evolution. Chromosome evolution plays an important role in adaptive evolution. Accurate chromosome-scale assembly is required to understand the role of chromosome evolution in Pucciniales. We took advantage of HiFi sequencing to construct a gapless, phased genome for Puccinia triticina. Further analyses revealed that the evolution of chromosome structures in rust lineage is shaped by the combination of transposable element bursts and segmental gene duplications. Chromosome comparisons of Puccinia triticina and other rusts suggested that frequent chromosomal arrangements may make remarkable contributions to high species diversity of rust fungi. Our results present the first gapless genome for Pucciniales and shed light on the feature of chromosome evolution in Pucciniales.

Genetic and phylogenetic characterization of Shiga toxin-producing Escherichia coli and enteropathogenic E. coli from livestock in Jiangsu by using whole-genome sequencing.

AIMS: There are knowledge gaps regarding STEC and EPEC strains in livestock in Jiangsu, China. This study aimed to evaluate the potential public health significance of STEC and EPEC strains isolated from livestock by determining the serotypes, virulence profiles, and genetic relationship with international STEC strains. METHODS AND RESULTS: A total of 68 STEC and 37 EPEC strains were obtained from 231 faecal sheep samples and 70 faecal cattle samples. By using whole-genome sequencing (WGS) analysis, all STEC belonged to 15 O: H serotypes, and the most prevalent serotypes were O6:H10 (19.1%), O155:H21 (14.7%), and O21:H25 (10.3%). The main Shiga toxin gene subtypes detected were stx1c (41.2%), stx1a (26.5%), stx2b (14.7%), and stx2k (14.7%). Only the STEC from cattle carried eae gene. Other adherence-associated or toxin-related genes, including lpfA (70.6%), iha (48.5%), subA (54.4%), and ehxA (33.8%), were found in STEC. All EPEC strains were bfpA-negative, and the predominant eae variants were eae-ß1 (62.2%), eae-ζ (21.6%), and eae-θ (8.1%). The core-genome multi-locus sequence typing (cgMLST) analysis revealed nine scattered clusters in STEC and one dominant cluster in EPEC. The strains with the same serotypes, including O22:H8 and O43:H2 in the two towns, possessed a closely genomic distance. The core genome single-nucleotide polymorphism (cgSNP) showed that part of STEC strains in this study was clustered with isolates possessing the same serotypes from the Netherlands, Sweden, and Xinjiang of China. Five serotypes of STEC isolates were associated with the clinical STEC strains from databases. CONCLUSION: This study provided the diverse serotypes and the virulence genes profiles in STEC and EPEC strains. Local strains possessed widely diverse and scattered clusters by cgMLST. Closely genomic correlation with clinical isolates displayed that part of the STEC strains may threaten to public health. SIGNIFICANCE AND IMPACT OF THE STUDY: Non-O157 STEC strains act as important pathogens for human infections. This study supports the increased surveillance work of non-O157 STEC rather than just O157 STEC in this region.

Emergence of mcr-1-Harboring Salmonella enterica Serovar Sinstorf Type ST155 Isolated From Patients With Diarrhea in Jiangsu, China.

Background: This study analyzed the antimicrobial resistance phenotypes and mechanisms of quinolone, cephalosporins, and colistin resistance in nontyphoidal Salmonella from patients with diarrhea in Jiangsu, China. Methods: A total of 741 nontyphoidal Salmonella isolates were collected from hospitals in major cities of Jiangsu Province, China between 2016 and 2017. Their susceptibility to commonly used antibiotics was evaluated by broth micro-dilution and sequencing analysis of resistance genes screened by a PCR method. For mcr-1 positive isolates, genetic relationship study was carried out by pulsed-field gel electrophoresis and multiloci sequence typing analysis. The transferability of these plasmids was measured with conjugation experiments and the genetic locations of mcr-1 were analyzed by pulsed-field gel electrophoresis profiles of S1-digested genomic DNA and subsequent Southern blot hybridization. Results: Among 741 nontyphoidal Salmonella isolates, the most common serotypes identified were S. Typhimurium (n=257, 34.7%) and S. Enteritidis (n=127, 17.1%), and the isolates showed 21.7, 20.6, and 5.0% resistance to cephalosporins, ciprofloxacin, and colistin, respectively. Among the 335 nalidixic acid-resistant Salmonella, 213 (63.6%) and 45 (13.4%) had at least one mutation in gyrA and parC. Among the plasmid-borne resistance, qnrS1 (85; 41.9%) and aac(6')-Ib-cr4 (75; 36.9%) were the most common quinolone resistance (PMQR) genes, while bla CTX-M-14 (n=35) and bla CTX-M-55 (n=46) were found to be dominant extended-spectrum beta-lactamase (ESBL) genes in nontyphoidal Salmonella. In addition, eight mcr-1-harboring strains were detected since 2016 and they were predominate in children under the age of 7years. Conjugation assays showed the donor Salmonella strain has functional and transferable colistin resistance and Southern blot hybridization revealed that mcr-1 was located in a high molecular weight plasmid. Conclusion: In nontyphoidal Salmonella, there is a rapidly increasing trend of colistin resistance and this is the first report of patients harboring mcr-1-positive Salmonella with a new ST type ST155 and new serotype S. Sinstorf. These findings demonstrate the necessity for cautious use and the continuous monitoring of colistin in clinical applications.

Potential climate benefits of reusable packaging in food delivery services. A Chinese case study.

In China, the food delivery packaging waste is increasing due to the rapid growth of the sector and the use of single-use packaging to transport the meals. In addition, the recycling rates of current municipal waste management are low. In this regard, this study aims at estimating the climate change impact of current food delivery packaging and its waste treatment, by performing a Life Cycle Assessment with a cradle-to-grave approach. In addition, this article explores the potential benefits of increasing the current recycling rates, the recycled content of the packaging as well as the use of reusable packaging. For this study, the food packaging of a typical dumpling-based meal of the popular Chinese restaurant Xijiade was selected. Based on this menu and the current Chinese consumption patterns, the food delivery packaging in China would have emitted about 13 million tons of CO2eq. Increasing current recycling rates to 35% would reduce 16% the emissions of single-use packaging, and further decrease (60%) could be found if half of the packaging was made of recycled material. In addition, if single-use packaging was replaced by reusable PP-based packaging (food container and carrier bag), the emissions would potentially be 63% lower than the current situation. In this case, doubling the recycling rates and the recycled content of the reusable food packaging would represent an extra 6 and 17% reduction of emissions, respectively.