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Abstract Objective We explored whether the Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification (R-M) systems are compatible and act together to resist plasmid attacks. Methods 932 global whole-genome sequences from GenBank, and 459 K. pneumoniae isolates from six provinces of China, were collected to investigate the co-distribution of CRISPR-Cas, R-M systems, and bla KPC plasmid. Conjugation and transformation assays were applied to explore the anti-plasmid function of CRISPR and R-M systems. Results We found a significant inverse correlation between the presence of CRISPR and R-M systems and bla KPC plasmids in K. pneumoniae, especially when both systems cohabited in one host. The multiple matched recognition sequences of both systems in bla KPC-IncF plasmids (97%) revealed that they were good targets for both systems. Furthermore, the results of conjugation assay demonstrated that CRISPR-Cas and R-M systems in K. pneumoniae could effectively hinder bla KPC plasmid invasion. Notably, CRISPR-Cas and R-M worked together to confer a 4-log reduction in the acquisition of bla KPC plasmid in conjugative events, exhibiting robust synergistic anti-plasmid immunity. Conclusions Our results indicate the synergistic role of CRISPR and R-M in regulating horizontal gene transfer in K. pneumoniae and rationalize the development of antimicrobial strategies that capitalize on the immunocompromised status of KPC-KP.

This study aims to understand and enhance the indicative significance of convective initiation (CI) products from Fengyun-4A (FY-4A) satellite for summer precipitation over the Qinghai-Tibet Plateau. Using the convective initiation (CI) products of FY-4A and precipitation data from the Global Precipitation Measurement Program (GPM), and based on the correspondence between the CI samples identified by the FY-4A CI product and the actual observed precipitation one hour after identifying the CI in the Qinghai-Tibet Plateau region from June to August 2022, three categories of the CI samples, including no precipitation CI, weak precipitation CI, and strong precipitation CI, were divided. Then a CI class recognition model was established and the model performance testing was conducted by combining atmospheric convective parameters and geographic location information, two machine learning methods, decision tree and random forest. The results show that there are significant regional differences in the precipitation situation within one hour after the occurrence of CI in the Qinghai Tibet Plateau region, with a higher proportion of no precipitation in the northwest region and a higher proportion of precipitation in the southeast region. By utilizing atmospheric convective parameters such as lift index, total cloud water, wind shear, middle and low level humidity, cloud bottom height, zero degree layer height and so on, it is possible to better distinguish whether there is precipitation and the strength of precipitation after the appearance of CI in the Qinghai Tibet Plateau. The random forests identify model have better performance for CI classification than decision tree, and the use of random forests identify model can more effectively classify summer CI on the Qinghai Tibet Plateau according to precipitation intensity.

Acute coronary syndrome (ACS) is a predominant cause of mortality, and the prompt and precise identification of this condition is crucial to minimize its impact. Recent research indicates that gut microbiota is associated with the onset, progression, and treatment of ACS. To investigate its role, we sequenced the gut microbiota of 38 ACS patients before and after percutaneous coronary intervention and statin therapy at three time points, examining differential species and metabolic pathways. We observed a decrease in the abundance of Parabacteroides, Escherichia, and Blautia in patients after treatment and an increase in the abundance of Gemalla, Klebsiella variicola, Klebsiella pneumoniae, and others. Two pathways related to sugar degradation were more abundant in patients before treatment, possibly correlated with disorders of sugar metabolism and risk factors, such as hyperglycemia, insulin resistance, and insufficient insulin secretion. Additionally, seven pathways related to the biosynthesis of vitamin K2 and its homolog were reduced after treatment, suggesting that ACS patients may gradually recover after therapy. The gut microbiota of patients treated with different statins exhibited notable differences after treatment. Rosuvastatin appeared to promote the growth of anti-inflammatory bacteria while reducing pro-inflammatory bacteria, whereas atorvastatin may have mixed effects on pro-inflammatory and anti-inflammatory bacteria while increasing the abundance of Bacteroides. Our research will provide valuable insights and enhance comprehension of ACS, leading to better patient diagnosis and therapy.

Abstract The association of blood pressure (BP) classification defined by the 2017 American College of Cardiology/American Heart Association (ACC/AHA) guideline with cardiometabolic multimorbidity (CMM) remains unclear. The present study aimed to investigate this research gap in the Chinese adults. Cross‐sectional data were collected from a population‐based cohort conducted in Southern China. Participants were categorized as having normal BP, elevated BP, stage 1 hypertension, and stage 2 hypertension according to the 2017 ACC/AHA guideline. CMM was defined as having two or more of the following diseases: coronary heart disease, stroke, and diabetes. The relationship between the BP classifications and CMM was examined by multivariate logistic regression. A total of 95 649 participants (mean age: 54.3 ± 10.2 years, 60.7% were women) were enrolled in this study. Multivariable‐adjusted logistic regression models revealed that stage 1 hypertension (odds ratio [OR], 1.35; 95% confidence interval [CI], 1.03–1.78) and stage 2 hypertension (OR, 3.53; 95% CI, 2.82–4.47) were significantly associated with a higher prevalence of CMM compared with normal BP. The association between stage 1 hypertension and CMM were profound in women (OR, 1.76; 95% CI, 1.17–2.67) and in the middle‐aged group (OR, 1.53; 95% CI, 1.02–2.35) compared with men and older individuals, respectively. Our study showed that among Chinese adults, stage 1 hypertension defined by the 2017 ACC/AHA guideline was already associated with higher odds of CMM compared with normal BP, particularly in women and middle‐aged participants. Managing stage 1 hypertension may be an important measure to prevent CMM in Chinese adults.

Abstract Background Cardiometabolic multimorbidity (CMM) and obesity represent two major health problems. The relationship between adiposity indices and CMM, however, remains understudied. This study aimed to investigate the associations of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), and conicity index (CI) with CMM among Chinese adults. Methods Data of 101,973 participants were collected from a population-based screening project in Southern China. CMM was defined as having two or more of the following diseases: coronary heart disease, stroke, hypertension, and diabetes. The relationship between the six adiposity indices and CMM was investigated by multivariate logistic regression and restricted cubic splines. Receiver operator characteristic curve, C-statistic and net reclassification index were used to estimate the discriminative and incremental values of adiposity indices on CMM. Results Logistic regression models showed the six adiposity indices were all significantly associated with the odds of CMM with non-linear relationships. For per SD increment, WC (Odds ratio [OR]: 1.66; 95% confidence interval (CI): 1.62–1.70) and WHtR (OR, 1.61; 95% CI, 1.58–1.65) were more significantly associated with a higher prevalence of CMM than BMI (OR, 1.55; 95% CI, 1.52–1.58) (all P

To understand the applicability of the temperature profile product of the FENGYUN-4A (FY-4A) geostationary interferometric infrared detector (GIIRS) in summer over the Qinghai–Tibet Plateau and to improve product quality, the error of GIIRS temperature products was analyzed based on radiosonde data. A long short-term memory network model (LSTM) was used to correct the GIIRS temperature profile product in summer over the plateau at a high altitude (above 500 hPa), and further evaluation of the corrected product was conducted. The results show that summertime GIIRS temperature retrievals over the Qinghai–Tibet Plateau had a positive bias above 150 hPa and a negative bias below 150 hPa, resulting in an overall negative bias. The root mean square error was between 2 and 2.9 K, and the root mean square error was relatively large at 100 hPa and above. The LSTM established in this study could effectively correct the GIIRS temperature over the plateau. The correlation and root mean square error of the corrected GIIRS temperature and the radiosonde observation temperature were significantly improved. Using a trained LSTM correction model to correct the hourly GIIRS temperature can improve the accuracy and usability of the product. After correction, the average bias of the GIIRS temperature compared to the ERA5 temperature product was reduced from −0.26 K to 0.06 K, and the root mean square error was reduced from 2.25 K to 1.25 K. The correction model can be applied to different seasons, and it can also correct the GIIRS temperature in larger areas based on other high-precision and high-resolution data, achieving good results, thus indicating that the correction model has universal applicability.

Central-Asian cyclone is one of the major synoptic systems that causes disastrous weather such as heavy rain, snowstorm, strong wind, and sand dust in Xinjiang. In order to deeply explore the structure and the formation of Central-Asian cyclones, taking a Central-Asian cyclone with typical northward path from August 11 to 12 in 2017 as an example, we analyze its activity characteristics and circulation situation, using conventional meteorological observations, FY satellite water vapor images, and NCEP reanalysis data. We reveal its vertical thermodynamic structural characteristics, with the focus on its mechanism of occurrence and development based on the quasi-geostrophic theory and the potential vorticity conservation. The main results are as follow. (1) The Central-Asian cyclone in front of the high trough at 500 hPa is due to the low vortex and shear line at 850 hPa and the divergence in upper atmosphere. Such condition and background is favorable to the occurrence of Central-Asian cyclone. (2) It can be seen from the water vaper images that the Central-Asian cyclone is in various stages from initial, development, and weakening, and the corresponding cloud systems in the three stages experience a transition from a baroclinic leafy shaped to a comma shaped, and then to a spiral shaped. (3) Vertical cross sections of physical fields in the center of surface cyclone show that there is an obvious cold front and a positive relative vorticity column at the beginning of the cyclone, and the upward motion is only located above the frontal zone. During the development of cyclone, the front intensified and steepened with strong upward motion both above and below. The positive relative vorticity at the lower level above the cyclone center increases, and the high positive relative vorticity at the upper level on the west side moves eastward towards the cyclone center. At the weakening stage of the cyclone, the front zone on its west side and the upward motion over and below the cyclone weakens, with the positive relative vorticity at lower level decreasing and the whole positive relative vorticity column becoming steeper. (4) The warm advection at 700 hPa increases significantly, the difference of vorticity advection between high and low levels increases, and the divergence at the high level strengthens, which leads to the occurrence and development of the cyclone. In addition, the subsidence of the high potential vorticity zone of dry air at the high level and the eastward moving of positive gradient center of potential vorticity contribute to the development of cyclone.

ABSTRACT Hypervirulent and carbapenem-resistant Klebsiella pneumoniae poses a severe threat to public health for its high pathogenicity, transmissibility, and drug resistance. This study aims to explore the evolutionary path and the role of Tn3 transposon in the virulence and carbapenem resistance transmission of K. pneumoniae. Bioinformatics analysis and some experimental tests such as plasmid conjugation experiments, antimicrobial susceptibility testing, and virulence-associated tests were performed to explore the virulence and drug resistance transmission. The complete genome sequencing, S1 nuclease pulsed-field gel electrophoresis, and bioinformatics analysis were used to investigate their transmission mechanism mediated by Tn3 transposons. Three hypervirulent and carbapenem-resistant K. pneumoniae isolates, which were obtained from different patients at different time points in the same ward, harbored a virulence plasmid and a carbapenem resistance plasmid. They were confirmed to have first evolved from hypervirulent isolates and then acquired a bla KPC-positive plasmid (CR-hvKp evolutionary pattern). The non-conjugative virulence plasmid pVir could be transferred to other bacterial strains via mobilization by the conjugative IncN/U-type plasmid pKPC, as well as by fusing with the conjugative pKPC plasmid (mediated by Tn3-based homologous recombination) to be self-transmissible, thus transferring drug resistance and virulence. The cointegration, pVir/KPC fusion plasmid, was further resolved into pVir and pKPC between the duplicated copies of the Tn3 transposon resolution site mediated by site-specific recombination. Therefore, Tn3 transposons can mediate hypervirulent and carbapenem-resistant K. pneumoniae strains transferring drug resistance and virulence to other bacteria. We must be vigilant to emerging transposon-mediated hypervirulent and carbapenem-resistant pathogens. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to most common antibiotics, becoming the most important and prevalent nosocomial opportunity pathogen. Besides, K. pneumoniae can also cause severe community-acquired infections, such as primary liver abscess and endophthalmitis. These pathogens are commonly referred to as hvKp. CRKP and hvKp have evolved separately, each occupying its own clonal lineage and exhibiting a variety of properties. Our study provides important insights into the evolutionary events related to the arousal of virulence and drug resistance in K. pneumoniae through plasmid transmission, mediated by Tn3 transposon. Our study also provides evidence that multiple mechanisms contribute to the successful transfer of non-conjugative virulence plasmid, and the involvement of transposons enhances the efficiency. A good knowledge of its transmission mechanisms is fundamental to finding effective strategies to combat these threatening pathogens. Transposons are widely present in bacteria, spreading resistance and virulence genes between the environment and humans. Therefore, emerging transposon-mediated hypervirulent and carbapenem-resistant pathogens should be highly valued.

Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacterales are prevalent worldwide and pose an alarming threat to public health. The incidence and transmission of blaKPC-2 gene via horizontal gene transfer (e.g. transposition) have been well documented. However, the dynamics of transposon structure bearing blaKPC-2 and their exact effects on the evolution and dissemination of blaKPC-2 gene are not well characterized. Here, we collected all 161 carbapenem-resistant Enterobacterales (CRE) isolates during the early stage of CRE pandemic. We observed that the prevalence of KPC-2-producing Enterobacterales was mediated by multiple species and sequence types (STs), and that blaKPC-2 gene was located on three diverse variants of Tn1721 in multi-drug resistance (MDR) region of plasmid. Notably, the outbreak of KPC-2-producing plasmid is correlated with the dynamics of transposon structure. Furthermore, we experimentally demonstrated that replicative transposition of Tn1721 and IS26 promotes horizontal transfer of blaKPC-2 and the evolution of KPC-2-producing plasmid. The Tn1721 variants appearing concurrently with the peak of an epidemic (A2- and B-type) showed higher transposition frequencies and a certain superior ability to propagation. Overall, our work suggests replicative transposition contributes to the evolution and transmission of KPC-2-producing plasmid and highlights its important role in the inter- and intra-species dissemination of blaKPC-2 gene in Enterobacterales.

K1/K2 hvKP strains acquire carbapenem-resistance plasmids, known as CR-hvKp, and carbapenem-resistant Klebsiella pneumoniae (CRKP) strains obtain virulence plasmids, recognized as hv-CRKP. The two different evolution patterns of hypervirulent combined carbapenem-resistant Klebsiella pneumoniae may lead to their different prevalence in hospitals. Our study aimed to investigate the prevalence of hv-CRKP and CR-hvKp strains and to analyze factors influencing their evolution and prevalence. We collected 890 K. pneumoniae genomes from GenBank and 530 clinical K. pneumoniae isolates from nine hospitals. Our study found that hv-CRKP strains were more prevalent than CR-hvKp strains and both were dominated by blaKPC-2 gene. The blaKPC-2-carrying plasmids could mobilize non-conjugative virulence plasmids from hvKp strains to CRKP strains. The conserved oriT of virulence plasmids and the widespread of conjugative helper plasmids were potential factors for the mobilization of non-conjugative virulence plasmids. HvKp strains with KPC plasmid could hardly simultaneously exhibit hypervirulence and carbapenem resistance as CRKP strains with virulence plasmid, and we found that rfaH mutation reduced capsular synthesis and increased carbapenem resistance of the CR-hvKp strain. In summary, this study revealed that hv-CRKP strains were more suitable for survival in hospital settings than CR-hvKp strains and the widespread conjugative KPC-producing plasmids contributed to the emergence and prevalence of hv-CRKP strains.

IntroductionHypervirulent Klebsiella pneumoniae produce an increased amount of capsular substance and are associated with a hypermucoviscous phenotype. Capsule production is regulated by capsular regulatory genes and capsular gene cluster variations. In the present study, we focus on the effect of rmpA and wcaJon capsule biosynthesis.MethodsPhylogenetic trees were constructed to analyze wcaJ and rmpA sequence diversity in different serotypes hypervirulent strains. Then mutant strains (K2044ΔwcaJ, K2044K1wcaJ, K2044K2wcaJand K2044K64wcaJ) were used to verify the effects of wcaJ and its diversity on capsule synthesis and strain virulence. Furthmore, the role of rmpA in capsular synthesis and its mechanisms were detected in K2044ΔrmpA strain.ResultsRmpA sequences are conversed in different serotypes. And rmpA promoted the production of hypercapsules by simultaneously acting on three promoters in cps cluster. Whereas wcaJ, its sequences are different in different serotypes, and its loss result in the termination of capsular synthesis. Moreover, the results verified that K2 wcaJ could form hypercapsule in K2044 strains (K1 serotype), but K64 wcaJ could not.DiscussionThe interaction of multiple factors is involved in capsule synthesis, including wcaJ and rmpA. RmpA, an known conserved capsular regulator gene, acts on cps cluster promoters to promote the production of the hypercapsule. WcaJ as initiating enzyme of CPS biosynthesis, its presence determines the synthesis of capsule. Besides, different from rmpA, wcaJ sequence consistency is limited to the same serotype, which cause wcaJ functioning in different serotype strains with sequence recognition specificity.

PurposeTo investigate the mechanisms of Klebsiella pneumoniae-induced pyogenic liver abscess (PLA).MethodsForty-three K. pneumoniae strains from PLAs and 436 from non-PLAs were collected. Their differences were compared for virulence genes and factors, sequence types, and serotypes. Virulence genes wzi, wzy-K1, and wzi+wzy-K1 were deleted in K. pneumoniae NTUH-K2044. Various analyses, such as transmission electron microscopy, neutrophil killing tests, and mouse lethality tests, were used to confirm the consequent changes.ResultsDifferences were found between K. pneumoniae strains from PLA and non-PLA samples for virulence genes and factors, including metabolism genes (allS and peg-344), capsular polysaccharide (CPS)-synthesis channel gene (wzy-K1), CPS-regulating genes (p-rmpA, p-rmpA2, and c-rmpA), and siderophore genes (iucA and iroN). When wzy-K1 was positive, the difference between PLA and non-PLA samples was only observed with c-rmpA. Δwzi, Δwzy-K1, and ΔwziΔwzy-K1 strains reverted to hypovirulence. In the Kupffer cell stimulation assay, interleukin (IL)-6, IL-12, IL-10, and transforming growth factor-β secretions were found to be equivalent in NTUH-K2044, Δwzi, Δwzy-K1, and ΔwziΔwzy-K1 groups. Lower IL-1β and higher tumor necrosis factor-α secretions were observed for Δwzi, Δwzy-K1, and ΔwziΔwzy-K1.ConclusionsHypercapsule production is the cornerstone of hypervirulence, regardless of exopolysaccharides. K1 K. pneumoniae-induced PLA may decrease core inflammatory cytokines rather than increase anti-inflammatory cytokines. Exopolysaccharides could also attenuate the inflammatory response to aid in the immune escape of K. pneumoniae.

Summary: Background: Mobile plasmids play a key role in spurring the global dissemination of multidrug-resistant (MDR) K. pneumoniae, while plasmid curing has been recognized as a promising strategy to combat antimicrobial resistance. Here we exploited a K. pneumoniae native CRISPR system to cure the high-risk IncFII plasmids. Methods: We examined matched protospacers in 725 completely sequenced IncFII plasmids from K. pneumoniae genomes. Then, we re-engineered a native CRISPR-Cas3 system and deliver the CRISPR-Cas3 system via conjugation. Plasmid killing efficiency and G. mellonella infection model were applied to evaluate the CRISPR-Cas3 immunity in vitro and in vivo. Findings: Genomic analysis revealed that most IncFII plasmids could be targeted by the native CRISPR-Cas3 system with multiple matched protospacers, and the targeting regions were highly conserved across different IncFII plasmids. This conjugative endogenous CRISPR-Cas3 system demonstrated high plasmid curing efficiency in vitro (8-log decrease) and in vivo (∼100% curing) in a Galleria mellonella infection model, as well as provided immunization against the invasion of IncFII plasmids once the system entering a susceptible bacterial host. Interpretation: Overall, our work demonstrated the applicability of using native CRISPR-mediated plasmid curing to re-sensitize drug-resistant K. pneumoniae to multiple antibiotics. This work provided strong support for the idea of utilizing native CRISPR-Cas systems to tackle AMR in K. pneumoniae. Funding: This work was supported by research grants National Natural Science Foundation of China [grant numbers 81871692, 82172315, 82102439, and 82202564], the Shanghai Science and Technology Commission [grant number 19JC1413002], and Shanghai Sailing Program [grant number 22YF1437500].

Forest stand structure is not only a crucial factor for regulating forest functioning but also an important indicator for sustainable forest management and ecosystem services. Although there exists a few national/global structure databases for natural forests, a country-wide synthetic structure database for plantation forests over China, the world’s largest player in plantation forests, has not been achieved. In this study, we built a country-wide synthetic stand structure database by surveying more than 600 peer-reviewed literature. The database covers tree species, mean stand age, mean tree height, stand density, canopy coverage, diameter at breast height, as well as the associated ancillary in-situ topographical and soil properties. A total of 594 published studies concerning diverse forest stand structure parameters were compiled for 46 tree species. This first synthesis for stand structure of plantation forests over China supports studies on the evolution/health of plantation forests in response to rapid climate change and intensified disturbances, and benefits country-wide sustainable forest management, future afforestation or reforestation planning. Potential users include those studying forest community dynamics, regional tree growth, ecosystem stability, and health, as well as those working with conservation and sustainable management. This dataset is freely accessible at http://www.doi.org/10.11922/sciencedb.j00076.00091.

ABSTRACT: Objectives: The aims of this study were to investigate the characteristics of Klebsiella pneumoniae meningitis and the impact of convergence of carbapenem resistance and hypervirulence on patient mortality.Methods: Antimicrobial resistance and virulence-related genes were investigated in 25 K. pneumoniae strains causing meningitis. Clinical data for 25 patients from February 2009 to February 2019 were evaluated. Multilocus sequence typing (MLST), serotyping, analysis of mobile genetic elements and pulsed-field gel electrophoresis (PFGE) were performed. GraphPad Prism was used for statistical analysis.Results: The mortality rate of patients with K. pneumoniae meningitis was 30.0%. Significant differences were observed between non-survivor and survivor groups regarding mechanical ventilation, peripheral deep vein catheter insertion and GCS score, but not sex, age or meningeal integrity destruction. Multidrug resistance was observed in 21 isolates. Rates of detection for each virulence gene ranged from 4.0% for wzy-K1 to 100.0% for entB. Detection rates of carbapenem-resistant K. pneumoniae (CRKP), hypervirulent K. pneumoniae (HvKP) and hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP) were 68.0%, 68.0% and 48.0%, respectively. In total, 16 clusters and 19 clones were identified among the 25 isolates. Mortality rates differed significantly between the non-Hv-CRKP (1/11) versus Hv-CRKP groups (5/9), but were comparable in the carbapenem-susceptible K. pneumoniae versus CRKP groups and the classical K. pneumoniae versus HvKP groups.Conclusions: Klebsiella pneumoniae meningitis is associated with high mortality. Klebsiella pneumoniae-induced meningitis has highly divergent origins. Convergence of carbapenem resistance and hypervirulence leads to high mortality in patients with K. pneumoniae meningitis, which is of great clinical concern.

Virulence plasmids of hypervirulent Klebsiella pneumoniae (hvKp) have the potential to transfer to drug-resistant strains or integrate with other plasmids, facilitating the genome evolution of threatening pathogens. We conducted an in-depth analysis of the publicly available 156 complete genome sequences of hvKp together with a multi-region clinical cohort of 171 hvKp strains from China to provide evidence for the virulence plasmid evolution. Virulence plasmids were frequently detected in the ST23 and ST11 K. pneumoniae strains. Multidrug-resistant hvKp (MDR-hvKp) occupied a large proportion of hvKp, and the coexistence of virulence and resistance plasmids may be the major cause. Virulence plasmids commonly possessed multiple replicons, of which IncFIBK was the most prevalent (84.6%). We identified 49 IncFIBK alleles among 583 IncFIBK plasmids, and they could be divided into Clades I, II, and III. We further observed that conjugative and non-conjugative virulence plasmids could be distinguished by IncFIBK genetic diversity, and IncFIBK subtyping could also indirectly indicate a chimeric preference of conjugative virulence plasmids. On this basis, we developed an open-access web tool called KpVR for IncFIBK subtyping. In conclusion, the genetic diversity of IncFIBK virulence plasmids could be used for tracking the evolution of virulence plasmids, and further preventing the emergence of MDR-hvKp strains.

Abstract Exosomes are nanosized bilayer membrane vesicles that may mediate intercellular communication by transporting bioactive molecules, including noncoding RNAs, mRNAs, and proteins. Research has shown that exosomes play an important role in acute myocardial infarction (AMI), but the function and regulation of exosomal long noncoding RNAs (lncRNAs) in AMI are unclear. Thus, RNA sequencing (RNA-Seq) was conducted to investigate the exosomal lncRNA transcriptome from MI patients and identified 65 differentially expressed lncRNAs between the MI and control groups. HCG15, one of the differentially expressed lncRNAs, was verified to have the highest correlation with cTnT by qRT-PCR, and it also contributed to the diagnosis of AMI by receiver operating characteristic (ROC) analysis. Upregulation of HCG15 expression facilitated cardiomyocyte apoptosis and inflammatory cytokine production and inhibited cell proliferation. We also confirmed that HCG15 was mainly wrapped in exosomes from AC16 cardiomyocytes under hypoxia, which contributed to cardiomyocyte apoptosis, the release of inflammatory factors, and inhibition of cell proliferation via the activation of the NF-κB/p65 and p38 pathways, whereas suppressing the expression of HCG15exerted opposite effects, In addition, Overexpression of HCG15 aggravated cardiac IR injury in C57BL/6J mice. This study not only helps elucidate exosomal lncRNA function in AMI pathogenesis but also contributes to the development of novel therapeutic strategies.

In recent years, the heavy ozone pollution events around the world have shown a sudden frequently increase, which has aroused widespread concern in the government and the public. It is well known that O3 is driven by photochemical reactions triggered by solar radiation (direct and indirect solar radiation), the O3 concentration calculated by chemical mechanism is mostly significantly lower than the actual O3 observation. Based on the study of the effect of meteorological conditions on the “additional increment” of O3 in three representative regions of Beijing, Hangzhou and Guangzhou from 2015 to 2020, an innovation diagnostic theory algorithm that the cross-cutting effects of atmospheric clouds on the chemical pattern of O3 solar radiation is established in this study. On this basis, a parametric evaluation method of O3 is established. The novelty of this study is 1) Comprehensive influence of the meteorological conditions and photochemical reactions mechanisms on the cross-cutting effects of O3 concentration are given. Especially low-level clouds in the troposphere, which have significantly large variable effects on the reflection and refraction of O3 through solar radiation. Theory quantitative algorithm of cloud scattering, cloud height, cloud volume and cloud structure changes, as well as feedback effects caused by water vapor condensation, which closely related to the transformation of O3 precursors are given. 2) Based on this, a parameterization method for quantitative O3 assessment and monitoring, which is a Parameterization for Linking Ozone pollution with Meteorological conditions. 3) Applying the theoretical algorithm and parameterization method of this study, comparing the changes of O3 in 2018 with 2019, an objective quantitative distinction between emission reduction and meteorological impact was made, showing that emission reduction still played a leading role, with a contribution rate of about 27%. This shows that the created quantitative algorithm of atmospheric cloud theory and the innovative parameterization method can provide an objective quantitative basis for O3 pollution decision-making and public emission reduction.

Introduction Current international guidelines recommend ECG monitoring after an ischaemic stroke to detect atrial fibrillation (AF) in order to prevent stroke recurrence. However, optimal strategies to detect AF and the downstream management to prevent stroke recurrence remain to be established. The objective of the study was to explore the use of long-term home-based ECG monitoring for AF detection and stroke prevention in patients with a history of stroke.Methods and analysis This prospective, randomised, open-label trial with blinded endpoint adjudication aimed to evaluate the efficacy of long-term home-based ECG monitoring for AF detection and stroke prevention in a 24-month period. Patients aged >18 years with a history of ischaemic stroke will be stratified according to the time from the index ischaemic stroke: 3 years and then randomised in 1:1 to (1) home-based AF screening and (2) control. The home-based AF screening system comprises (1) a handheld single-lead ECG recorder (Comfit Healthcare Devices, Hong Kong SAR, China) and (2) a patient-facing smartphone application specially designed for the study. Patients randomised to the home-based AF group will record a 30 s single-lead ECG using a specially designed handheld ECG device every morning or when symptomatic. All remotely obtained data will be automatically transmitted in real-time through the study smartphone application to a secured cloud hosting and analysed using an artificial intelligence-based diagnostic system. When a diagnosis of AF is made with the system, the patients will be called back for a formal cardiology consultation within 1 week. The primary endpoint is the time to first detection of AF at 24 months of follow-up. Secondary endpoints include recurrent stroke or transient ischaemic attack, initiation of long-term anticoagulation therapy, hospitalisation for heart failure, cardiovascular death and all-cause death.Ethics and dissemination The study protocol has been approved by the institutional review board of The University of Hong Kong, and Hong Kong West Cluster, Hospital Authority, Hong Kong SAR, China. Results will be published in peer-reviewed journals.Trial registration number NCT04523649.

ObjectiveTo investigate the epidemiology of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-HvKP) and hypervirulent carbapenem-resistant Klebsiella pneumoniae (Hv-CRKP).MethodsTotally 436 K. pneumoniae strains were collected from 7 hospitals in mainland China between 2017.01 and 2018.02. Sequence types, serotypes, antimicrobial-resistance and virulence genes were analyzed. Additionally, string test, capsule stain, Periodic Acid Schiff stain, fitness analysis, quantitative real-time PCR and mouse lethality test were also performed. Molecular combinations were used to screen putative blaKPC(+)-HvKP and Hv-blaKPC(+)-KP, followed by the confirmation of mouse lethality test.ResultsDiverse detection rates were found for the virulence genes, ranging from c-rmpA (0.0%) to entB (100.0%). According to the molecular criteria, 127, 186, 9 and 26 strains were putatively denoted as HvKP, blaKPC(+)-KP, blaKPC(+)-HvKP and Hv-blaKPC(+)-KP. Mouse lethality test confirmed 2 blaKPC(+)-HvKP strains (JS184 and TZ20) and no Hv-blaKPC(+)-KP. JS184 showed K2 serotype, thin capsule, positive exopolysaccharid and string test. TZ20 presented K20 serotype, thin capsule, negative exopolysaccharide and string test. Compared with the positive control NTUH-K2044, equal galF expression and growth curves were confirmed for JS184 and TZ20.ConclusionsMolecular determination of CR-HvKP and Hv-CRKP brings remarkable bias compared with mouse lethality test. The exact prevalence of CR-HvKP is less than 1.0%, which of Hv-CRKP is much lower.

Background Many fundus imaging modalities measure ocular changes. Automatic retinal vessel segmentation (RVS) is a significant fundus image-based method for the diagnosis of ophthalmologic diseases. However, precise vessel segmentation is a challenging task when detecting micro-changes in fundus images, e.g., tiny vessels, vessel edges, vessel lesions and optic disc edges. Methods In this paper, we will introduce a novel double branch fusion U-Net model that allows one of the branches to be trained by a weighting scheme that emphasizes harder examples to improve the overall segmentation performance. A new mask, we call a hard example mask, is needed for those examples that include a weighting strategy that is different from other methods. The method we propose extracts the hard example mask by morphology, meaning that the hard example mask does not need any rough segmentation model. To alleviate overfitting, we propose a random channel attention mechanism that is better than the drop-out method or the L2-regularization method in RVS. Results We have verified the proposed approach on the DRIVE, STARE and CHASE datasets to quantify the performance metrics. Compared to other existing approaches, using those dataset platforms, the proposed approach has competitive performance metrics. (DRIVE: F1-Score = 0.8289, G-Mean = 0.8995, AUC = 0.9811; STARE: F1-Score = 0.8501, G-Mean = 0.9198, AUC = 0.9892; CHASE: F1-Score = 0.8375, G-Mean = 0.9138, AUC = 0.9879). Discussion The segmentation results showed that DBFU-Net with RCA achieves competitive performance in three RVS datasets. Additionally, the proposed morphological-based extraction method for hard examples can reduce the computational cost. Finally, the random channel attention mechanism proposed in this paper has proven to be more effective than other regularization methods in the RVS task.

ABSTRACTKlebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) have disseminated worldwide and emerged as major threats to public health. Of epidemiological significance, the international pandemic of KPC-KP is primarily associated with CG258 isolates and blaKPC-IncF plasmids. CRISPR-Cas system is an adaptive immune system that can hinder gene expansion driven by horizontal gene transfer. Because of blaKPC-IncF plasmids are favored by CG258 K. pneumoniae, it was of interest to examine the co-distribution of CRISPR and blaKPC-IncF plasmids in such isolates. We collected 459 clinical K. pneumoniae isolates in China and collected 203 global whole-genome sequences in GenBank to determine the prevalence of CRISPR-Cas systems. We observed that CRISPR-Cas system was significantly scarce in the CG258 lineage and blaKPC-positive isolates. Furthermore, the results of conjugation and plasmid stability assay fully demonstrated the CRIPSR-Cas system in K. pneumoniae could effectively hindered blaKPC-IncF plasmids invasion and existence. Notably, most blaKPC-IncF plasmids were also proved to be good targets of CRISPR owing to carry matched and functional protospacers and PAMs. Overall, our work suggests that type I-E CRISPR-Cas systems could impact the spread of blaKPC in K. pneumoniae populations, and the scarcity of CRISPR-Cas system was one of potential factors leading to the propagation of blaKPC-IncF plasmids in CG258 K. pneumoniae.

Abstract Background Hypertension is a highly prevalent disease and the leading cause of chronic kidney disease (CKD). Metabolic syndrome could also be the risk factor for CKD. We sought to study the association between metabolic syndrome components and the prevalence of CKD in patients with hypertension. Methods We carried out a multi-center cross-sectional study from Apr. 2017- Apr. 2018 in 15 cities in China. Results A total of 2484 patients with hypertension were enrolled. Among them, 56% were male and the average age was 65.12 ± 12.71 years. The systolic BP/diastolic BP was 142 ± 18/83 ± 12 mmHg. Metabolic syndrome components turned out to be highly prevalent in patients with hypertension, ranging from 40 to 58%. The prevalence of chronic kidney disease reached 22.0%. Multi-variate logistic analysis revealed that elevated triglyceride (TG) (OR = 1.81, 95% CI 1.28–2.57, p

The emergence of hypervirulent and carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) has become a hot topic and confounding problem for clinicians and researchers alike. Conjugative virulence plasmids have the potential to cause more threatening dissemination of hv-CRKP strains. We previously identified K2606, a CG23 clinical hypervirulent strain of Klebsiella pneumoniae harboring a conjugative virulence plasmid designated pK2606. In this study we examined hypervirulence levels using assays of biofilm formation, serum resistance, and wax larvae and mouse in vivo infection models. Moreover, to define the transfer ability of pK2606 and whether this confers hypervirulence to other strains we performed plasmid transconjugation experiments between K2606 and the ST11 CRKP strain HS11286 along with E. coli J53. We found that although biofilm formation and serum resistance were not significantly increased, the transconjugants acquired the ability of produce high level of siderophores and also caused high mortality of wax larvae and mice. Furthermore, we identified pK2606-like conjugative virulence plasmids in GenBank, providing evidence that such plasmids may have begun to spread throughout China. These findings provide an evidence base for the possible mechanisms of the emergence of hv-CRKP strains and highlight the potential of pK2606-like conjugative virulence plasmids to spread worldwide.

ObjectiveTo investigate the overall distributions of key virulence genes in Klebsiella pneumoniae, especially the hypervirulent blaKPC-positive K. pneumoniae (Hv-blaKPC(+)-KP).MethodsA total of 521 complete genomes of K. pneumoniae from GenBank were collected and analyzed. Multilocus sequence typing, molecular serotyping, antibiotic-resistance, virulence genes and plasmid replicon typing were investigated.ResultsPositive rates of virulence genes highly varied, ranging from 2.9 (c-rmpA/A2) to 99.6% (entB). Totally 207 strains presented positive fimH, mrkD, entB and wzi and 190 showed positive fimH, mrkD, entB, irp2 and wzi, which were the two primary modes. A total of 94, 165 and 29 strains were denoted as hypervirulent K. pneumoniae (HvKP), blaKPC(+)-KP and Hv-blaKPC(+)-KP. ST11 accounted for 17 among the 29 Hv-blaKPC(+)-KP strains; Genes iucA, p-rmpA2 and p-rmpA were positive in 28, 26 and 18 Hv-blaKPC(+)-KP strains respectively. Among the 29 Hv-blaKPC(+)-KP strains exhibiting four super clusters from GenBank, IncHI1B plasmids carrying virulence genes and IncFII ones with blaKPC were responsible for both 23 strains respectively.ConclusionsPositive rates of virulence genes vary remarkably in K. pneumoniae. Genes iucA, p-rmpA2 and p-rmpA were primary ones inducing Hv-blaKPC(+)-KP. IncHI1B plasmids carrying virulence genes and IncFII ones with blaKPC constitute the primary combination responsible for Hv-blaKPC(+)-KP. The making of Hv-blaKPC(+)-KP is mostly via blaKPC(+)-KP acquiring another plasmid harboring virulence genes.

Infection caused by carbapenem-resistant Klebsiella pneumoniae has become a major healthcare threat and KPC-2 enzyme is a dominant factor mediating carbapenems resistance in K. pneumoniae. This study was designed to determine the genetic environment of blaKPC-2, which prevailed in clinical K. pneumoniae isolates recovered in Huashan Hospital, Shanghai, China. Forty-two clinical isolates were included in this study by blaKPC-2 screening. After multilocus sequence typing and plasmid analyses of PCR-based replicon typing (PBRT), junction PCR, mapping PCR and crossing PCR assays, primer walking, and amplicon sequencing were used to analyze the genetic environment of the blaKPC-2 gene. ST423, ST65, ST977, and ST11 were all detected in KPC-2-producing K. pneumoniae. Two types of blaKPC-2-bearing genetic structure were found: Tn1721-blaKPC-2-Tn3 and Tn1721-blaKPC-2-ΔTn3-IS26; and were carried in IncX and IncFII plasmids, respectively. In conclusion, the genetic environment of the blaKPC-2 gene was diverse and Tn1721-blaKPC-2-ΔTn3-IS26 was dominant in clinical K. pneumoniae isolates in Huashan Hospital. This study sheds some light on the genetic environment and should foster further studies about the mechanism of the blaKPC-2 dissemination. Keywords: Klebsiella pneumoniae, blaKPC, Genetic environment

A 26-year-old patient with mirror-image dextrocardia and situs inversus experienced a transient ischemic attack. We suspected that a patent foramen ovale was the reason. A Cardi-O-Fix occluder was used to close the patent foramen ovale with a mirror-reversed rotation of the radiologic views. During the 18-month follow-up, no symptoms of the transient ischemic attack appeared again.

Carbapenemase-producing Klebsiella pneumoniae (KPC) has emerged and spread throughout the world. A retrospective analysis was performed on carbapenem-resistant K. pneumoniae isolated at our teaching hospital during the period 2009–2010, when the initial outbreak occurred. To determine the mechanism(s) that underlies the increased infectivity exhibited by KPC, Multilocus Sequence Typing (MLST) was conducted. A series of plasmids was also extracted, sequenced and analyzed. Concurrently, the complete sequences of blaKPC−2-harboring plasmids deposited in GenBank were summarized and aligned. The blaKPC−2 and KlcAHS genes in the carbapenem-resistant K. pneumoniae isolates were examined. E. coli strains, carrying different Type I Restriction and Modification (RM) systems, were selected to study the interaction between RM systems, anti-RM systems and horizontal gene transfer (HGT). The ST11 clone predominated among 102 carbapenem-resistant K. pneumoniae isolates, all harbored the blaKPC−2 gene; 98% contained the KlcAHS gene. KlcAHS was one of the core genes in the backbone region of most blaKPC−2 carrying plasmids. Type I RM systems in the host bacteria reduced the rate of pHS10842 plasmid transformation by 30- to 40-fold. Presence of the anti-restriction protein, KlcAHS, on the other hand, increased transformation efficiency by 3- to 6-fold. These results indicate that RM systems can significantly restrict HGT. In contrast, KlcAHS can disrupt the RM systems and promote HGT by transformation. These findings suggest that the anti-restriction protein, KlcAHS, represents a novel mechanism that facilitates the increased transfer of blaKPC-2 and KlcAHS-carrying plasmids among K. pneumoniae strains.

The global emergence of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae poses a major public health threat requiring immediate and aggressive action. Some older generation antibiotics, such as trimethoprim, serve as alternatives for treatment of infections. Here, we determined the complete nucleotide sequence of plasmid pHS091147, which co-harbored the carbapenemase (blaKPC-2) and trimethoprim resistance genes (dfrA25) from a Klebsiella pneumoniae sequence type (ST) 11 clone recovered in Shanghai, China. pHS091147 had three replication genes, several plasmid-stability genes and an intact type IV secretion system gene cluster. Besides blaKPC-2 and dfrA25, pHS091147 carried several other resistance genes, including β-lactamase genes blaTEM-1 and blaCTX-M-14, sulphonamide resistance gene sul1, a quinolone resistance gene remnant (ΔqnrB2), and virulence associated gene iroN. Notably, the multidrug-resistance region was a chimeric structure composed of three subregions, which shared strong sequence homology with several plasmids previously assigned in Genbank. To our knowledge, this is the first report of the co-localization of blaKPC-2 and dfrA25 on a novel putative multi-replicon plasmid in a Klebsiella pneumoniae ST11 clone.

Jatrorrhizine was considered as one of the active constituents of Coptis chinensis Franch. Herein, jatrorrhizine derivatives with substituted amino groups linked at the 3-position were designed, synthesized, and biologically evaluated as inhibitors of acetylcholinesterase. Jatrorrhizine derivatives inhibited the activity of acetylcholinesterase (AChE) to a greater extent than the lead compound jatrorrhizine. All these jatrorrhizine derivatives were proved to be potent inhibitors of acetylcholinesterase (AChE) with submicromolar IC50 values, but less sensitive to butyrylcholinesterase (BuChE), which suggests that these jatrorrhizine derivatives are selective for AChE/BuChE. Compound 3g gave the most potent inhibitor activity for AChE (IC50 = 0.301 μM), which is greater than the lead compound jatrorrhizine. All these results demonstrated that these jatrorrhizine derivatives are potential inhibitors for AChE.

ZBR is the most popular routing protocol in ZigBee network currently, but in some cases, it is not very efficient. In this paper a new improved ZBR is proposed which add the network address range field of neighbor node in the neighbor table. So the node can distinguish whether the destination node is the descendants of its neighbor. Compared with the previous protocols OI-ZBR, NI- ZBR and ZBR in NS-2, NP-ZBR shows its merits in the average hop, end to end delay and the first packet delay.

With the increasing temperature and intensified drought, global climate change has profound impacts on tree growth in temperate regions, which consequently regulates terrestrial-atmosphere biogeochemical processes and biophysical feedbacks. Thus, increasing numbers of studies have addressed the long-term annual trends in tree growth and their response to climate change at diverse spatial scales. However, the potential divergence in tree growth trends and growth variability (represented by coefficient of variance) in different seasons across large-scale climate gradients remains poorly understood. Here, we investigated the tree growth trends and growth variability in different seasons across diverse drought conditions in forested regions over northeastern China during the period 1982–2015, using both remote sensing observations and in situ tree-ring measurements. We found clear seasonal divergence in tree growth trends during 1982–2015, and the apparent increase was mainly observed in spring and autumn, attributed mainly to the increase in spring temperature and autumn solar radiation, respectively, but not in summer. The magnitudes of increasing trends in tree growth decrease with the increase of the multi-year average dryness index (MAI) in semi-arid areas (1.5 < MAI < 4.0) in all seasons. We further revealed that the interannual variability in tree growth was much larger in the semi-arid regions than in the humid and semi-humid regions in all seasons, and tree growth variability was significantly and negatively correlated with the variations in temperature and water deficit. Our findings improve our understanding of seasonal divergence in tree growth trends and provide new insights into spatial patterns in forest vulnerability in a warmer and drier climate.

Plasmids play critical roles in bacterial fitness and evolution of Pseudomonas aeruginosa. Here two plasmids found in a drug-resistant P. aeruginosa clinical isolate HS87 were completely sequenced. The pHS87b plasmid (11.2 kb) carries phage-related genes and function-unknown genes. Notably, pHS87b encodes an integrase and has an adjacent tRNAThr-associated attachment site. A corresponding integrated form of pHS87b at the tRNAThr locus was identified on the chromosome of P. aeruginosa, showing that pHS87b is able to site-specifically integrate into the 3'-end of the tRNAThr gene. The pHS87a plasmid (26.8 kb) displays a plastic structure containing a putative replication module, stability factors and a variable region. The RepA of pHS87a shows significant similarity to the replication proteins of pPT23A-family plasmids. pHS87a carries a transposon Tn6049, a truncated insertion sequence ΔIS1071 and a Tn402-like class 1 integron which contains an aacA4 cassette that may confer aminoglycoside resistance. Thus, pHS87b is a site-specific integrative plasmid whereas pHS87a is a plastic antibiotic resistance plasmid. The two native plasmids may promote the fitness and evolution of P. aeruginosa.