ESKAPE in China: epidemiology and characteristics of antibiotic resistance

The escalation of antibiotic resistance and the diminishing antimicrobial pipeline have emerged as significant threats to public health. The ESKAPE pathogens - Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. - were initially identified as critical multidrug-resistant bacteria, demanding urgently effective therapies. Despite the introduction of various new antibiotics and antibiotic adjuvants, such as innovative β-lactamase inhibitors, these organisms continue to pose substantial therapeutic challenges. People's Republic of China, as a country facing a severe bacterial resistance situation, has undergone a series of changes and findings in recent years in terms of the prevalence, transmission characteristics and resistance mechanisms of antibiotic resistant bacteria. The increasing levels of population mobility have not only shaped the unique characteristics of antibiotic resistance prevalence and transmission within People's Republic of China but have also indirectly reflected global patterns of antibiotic-resistant dissemination. What's more, as a vast nation, People's Republic of China exhibits significant variations in the levels of antibiotic resistance and the prevalence characteristics of antibiotic resistant bacteria across different provinces and regions. In this review, we examine the current epidemiology and characteristics of this important group of bacterial pathogens, delving into relevant mechanisms of resistance to recently introduced antibiotics that impact their clinical utility in China.

Epidemiology and clinical features of Skin and Soft Tissue Infections Caused by PVL-Positive and PVL-Negative Methicillin-Resistant Staphylococcus aureus Isolates in inpatients in China: a single-center retrospective 7-year study

Previous studies have mainly focused on outpatient cases of skin and soft tissue infections (SSTIs), with limited attention to inpatient occurrences. Thus, we aimed to compare the clinical parameters of inpatients with SSTIs, performed genomic characterization, and determined the subtypes of Panton-Valentine leucocidin (PVL) bacteriophages of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from these patients. We found that PVL-positive patients had shorter hospital stays (mean, 9 vs. 24 days; p < 0.001) and abscess resolution durations (mean, 8 vs. 13 days; p < 0.01). PVL-positive MRSA-induced SSTIs were more frequently associated with abscesses [36/55 (65.5%) vs. 15/124 (12.1%), p < 0.001], with 52.7% undergoing incision and drainage; over 80% of PVL-negative patients received incision, drainage, and antibiotics. In PVL-positive patients receiving empirical antibiotics, anti-staphylococcal agents such as vancomycin and linezolid were administered less frequently (32.7%, 18/55) than in PVL-negative patients (74.2%, 92/124), indicating that patients with PVL-positive SSTIs are more likely to require surgical drainage rather than antimicrobial treatment. We also found that the ST59 lineage was predominant, regardless of PVL status (41.3%, 74/179). Additionally, we investigated the linear structure of the lukSF-PV gene, revealing that major clusters were associated with specific STs, suggesting independent acquisition of PVL by different strain types and indicating that significant diversity was observed even within PVL-positive strains detected in the same facility. Overall, our study provides comprehensive insights into the clinical, genetic, and phage-related aspects of MRSA-induced SSTIs in hospitalized patients and contributes to a more profound understanding of the epidemiology and evolution of these pathogens in the Chinese population.

Clinical and Economic Evaluation of Blood Culture Whole Process Optimisation in Critically Ill Adult Patients With Positive Blood Cultures

OBJECTIVES

Optimising blood culture processing is important to ensure that bloodstream infections are accurately diagnosed while minimising adverse events caused by antibiotic abuse. This study aimed to evaluate the impact of optimised blood culture processes on antibiotic use, clinical outcomes and economics in intensive care unit (ICU) patients with positive blood cultures.

METHODS

From March 2020 to October 2021, this microbiology laboratory implemented a series of improvement measures, including the clinical utility of Fastidious Antimicrobial Neutralization (FAN® PLUS) bottles for the BacT/Alert Virtuo blood culture system, optimisation of bottle reception, graded reports and an upgraded laboratory information system. A total of 122 ICU patients were included in the pre-optimisation group from March 2019 to February 2020, while 179 ICU patients were included in the post-optimisation group from November 2021 to October 2022.

RESULTS

Compared with the pre-optimisation group, the average reporting time of identification and antimicrobial sensitivity was reduced by 16.72 hours in the optimised group. The time from admission to targeted antibiotic therapy within 24 hours after receiving both the Gram stain report and the final report were both significantly less in the post-optimisation group compared with the pre-optimisation group. The average hospitalisation time was reduced by 6.49 days, the average antimicrobial drug cost lowered by $1720.85 and the average hospitalisation cost by $9514.17 in the post-optimisation group.

CONCLUSIONS

Optimising blood culture processing was associated with a significantly increased positive detection rate, a remarkable reduction in the length of hospital stay and in hospital costs for ICU patients with bloodstream infections.

Clinical relevance, mechanisms, and evolution of polymyxin B heteroresistance carbapenem-resistant Klebsiella pneumoniae: A genomic, retrospective cohort study

OBJECTIVES

To study the clinical relevance, mechanisms, and evolution of polymyxin B (POLB) heteroresistance (PHR) in carbapenem-resistant Klebsiella pneumoniae (CRKP), potentially leading to a significant rise in POLB full resistant (FR) CRKP.

METHODS

Total of 544 CRKP isolates from 154 patients treated with POLB were categorized into PHR and POLB non-heteroresistance (NHR) groups. We performed statistical analysis to compare clinical implications and treatment responses. We employed whole-genome sequencing, bioinformatics, and PCR to study the molecular epidemiology, mechanisms behind PHR, and its evolution into FR.

RESULTS

We observed a considerable proportion (118 of 154, 76.62%) of clinically undetected PHR strains before POLB exposure, with a significant subset of them (33 of 118, 27.97%) evolving into FR after POLB treatment. We investigated the clinical implications, epidemiological characteristics, mechanisms, and evolutionary patterns of PHR strains in the context of POLB treatment. About 92.86% (39 of 42) of patients had PHR isolates before FR, highlighting the clinical importance of PHR. the ST15 exhibited a notably lower PHR rate (1 of 8, 12.5% vs. 117 of 144, 81.25%; p < 0.01). The ST11 PHR strains showing significantly higher rate of mgrB mutations by endogenous insertion sequences in their resistant subpopulation (RS) compared with other STs (78 of 106, 73.58% vs. 4 of 12, 33.33%; p < 0.01). The mgrB insertional inactivation rate was lower in FR isolates than in the RS of PHR isolates (15 of 42, 35.71% vs. 84 of 112, 75%; p < 0.01), whereas the pmrAB mutation rate was higher in FR isolates than in the RS of PHR isolates (8 of 42, 19.05% vs. 2 of 112, 1.79%; p < 0.01). The evolution from PHR to FR was influenced by subpopulation dynamics and genetic adaptability because of hypermutability.

DISCUSSION

We highlight significant genetic changes as the primary driver of PHR to FR in CRKP, underscoring polymyxin complexity.

Females adopt sexual catalepsy to facilitate mating

Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner. Female sexual cannibalism, a particularly dramatic illustration of this conflict, is widespread in certain animal taxa including spiders. Nevertheless, females of some funnel weaving spiders that are generally aggressive to conspecifics enter a cataleptic state after male courtship, ensuring the males can mate without risk of attack. In this study, we demonstrated that the physical posture and duration, metabolites, and central neurotransmitters of females of Aterigena aculeata in sexual catalepsy closely resemble females in thanatosis but are distinct from those in anesthesia, indicating that the courted females feign death to eliminate the risk of potentially aggressive responses and thereby allow preferred males to mate. Unlike the taxonomically widespread thanatosis, which generally represents a deceptive visual signal that acts against the interest of the receivers, sexual catalepsy of females in the funnel weaving spiders may deliver a sexual-receptive signal to the courting males and thereby benefit both the signal senders and receivers. Therefore, sexual catalepsy in A. aculeata may not reflect a conflict but rather a confluence of interest between the sexes.

Comparison of in vitro synergy between polymyxin B or colistin in combination with 16 antimicrobial agents against multidrug-resistant Acinetobacter baumannii isolates

PURPOSES

This study determined the synergy of polymyxin B (POLB) and colistin (COL) with 16 other tested antimicrobial agents in the inhibition of multidrug-resistant Acinetobacter baumannii (MDR-AB).

METHODS

We used chequerboard assays to determine synergy between the drugs against 50 clinical MDR-AB from a tertiary hospital in the Zhejiang province in 2019, classifying combinations as either antagonistic, independent, additive, or synergistic. The efficacy of hit combinations which showed highest synergistic rate were confirmed using time-kill assays.

RESULTS

Both POLB and COL displayed similar bactericidal effects when used in combination with these 16 tested drugs. Antagonism was only observed for a few strains (2%) exposed to a combination of POLB and cefoperazone/sulbactam (CSL). A higher percentage of synergistic combinations with POLB and COL were observed with rifabutin (RFB; 90%/96%), rifampicin (RIF; 60%/78%) and rifapentine (RFP; 56%/76%). Time-kill assays also confirmed the synergistic effect of POLB and rifamycin class combinations. 1/2 MIC rifamycin exposure can achieve bacterial clearance when combined with 1/2 MIC POLB or COL.

CONCLUSION

Nearly no antagonism was observed when combining polymyxins with other drugs by both chequerboard and time-kill assays, suggesting that polymyxins may be effective in combination therapy. The combinations of POLB/COL with RFB, RIF, and RFP displayed neat synergy, with RFB showing the greatest effect.

In Vitro Antibacterial Activity of Ceftobiprole and Comparator Compounds against Nation-Wide Bloodstream Isolates and Different Sequence Types of MRSA

Bloodstream infections by bacteria, especially multidrug-resistant bacteria, remain a worldwide public health concern. We evaluated the antibacterial activity of ceftobiprole and comparable drugs against different bloodstream isolates and different sequence types of methicillin-resistant Staphylococcus aureus (MRSA) in China. We found that MRSA, methicillin-susceptible Staphylococcus aureus (MSSA), and methicillin-susceptible coagulase-negative Staphylococcus (MSCNS) displayed ceftobiprole sensitivity rates of >95%, which are similar to the rates for linezolid, daptomycin, and vancomycin. Of the tested MRCNS strains, 90.4% were sensitive to ceftobiprole. The sensitivities of ST59, ST398, and ST22 MRSA to ceftobiprole were higher than that of ST239. Ceftobiprole's MIC50/90 value against Enterococcus faecalis was 0.25/2 mg/L, whereas Enterococcus faecium was completely resistant to this drug. Ceftobiprole exhibited no activity against ESBL-positive Enterobacterales, with resistance rates between 78.6% and 100%. For ESBL-negative Enterobacterales, excluding Klebsiella oxytoca, the sensitivity to ceftobiprole was comparable to that of ceftazidime, ceftriaxone, and cefepime. The MIC50/90 value of ceftobiprole against Pseudomonas aeruginosa was 2/16 mg/L, and for Acinetobacter baumannii, it was 32/>32 mg/L. Thus, ceftobiprole shows excellent antimicrobial activity against ESBL-negative Enterobacterales and Pseudomonas aeruginosa (comparable to that of ceftazidime, ceftriaxone, and cefepime); however, it is not effective against ESBL-positive Enterobacterales and Acinetobacter baumannii. These results provide important information to clinicians.

Notes on species of Talaus Simon, 1886 (Araneae, Thomisidae) from China, with descriptions of two new species

Taxonomic notes on the Talaus species from China are provided. Two new species, T.yuyang Yao & Liu, sp. nov. and T.zhangjiangkou Yao & Liu, sp. nov. are described and illustrated, and a further three species are redescribed based on their genitalic characters: T.dulongjiang Tang, Yin, Ubick & Peng, 2008, T.niger Tang, Yin, Ubick & Peng, 2008, and T.sulcus Tang & Li, 2010. The species T.xiphosus Zhu & Ono, 2007 is considered a junior synonym of T.triangulifer Simon, 1886 based on an examination of many recently collected female and male specimens from Guangxi Province, China. Diagnoses, detailed illustrations and a map of distributional records of the six treated species of Talaus in China are provided.

Thiyl Radical Trapped by Cobalt Catalysis: An Approach to Markovnikov Thiol-Ene Reaction

In the presence of a thiyl radical species, the catalytic Markovnikov thiol-ene reaction is challenging because it prefers to proceed via a radical pathway, thereby leading to anti-Markovnikov selectivity. In this work, a rare example of thiyl radical engaged in Markovnikov thiol-ene reaction enabled by cobalt catalysis is reported. This protocol features the avoidance of unique oxidants, exclusive regioselectivity, and broad substrate scope. Scalable synthesis and late-stage modification of complex molecules demonstrate the practicability of the protocol.

A preliminary exploration on the mechanism of the carbapenem-resistance transformation of Serratia marcescens in vivo

BACKGROUND

The infection of carbapenem-resistant organisms was a huge threat to human health due to their global spread. Dealing with a carbapenem-resistant Serratia marcescens (CRSM) infection poses a significant challenge in clinical settings. This study aims to provide insights into strategies for controlling CRSM infection by exploring the transformation mechanism of carbapenem-resistance.

METHODS

We used whole genome sequencing (WGS) to investigate the mechanism of carbapenem resistance in 14 S. marcescens isolates in vivo. The expression level of related genes and the minimum inhibitory concentration of meropenem (MICMEM) were also evaluated to confirm the mechanism of carbapenem resistance.

RESULTS

Seven groups of S. marcescens, each consisting of two strains, were collected from a hospital and displayed a shift in MICMEM from low to high levels. Homology analysis revealed that the isolates in five groups were significantly different from the remaining two. WGS and experimental evidence indicated that four groups of strains developed carbapenem resistance by acquiring the blaKPC (obtaining group), while two groups (persisting group) increased the expression level of the blaKPC. In contrast, isolates in the last group (missing group) did not carry the blaKPC. All strains possessed multiple β-lactamase genes, including blaCTX-M-14, blaSRT-1, and blaSRT-2. However, only in the missing group, the carbapenem-resistant strain lost an outer membrane protein-encoding gene, leading to increased blaCTX-M-14 expression compared to the carbapenem-susceptible strain.

CONCLUSION

The study findings suggest that S. marcescens strains developed diverse carbapenem resistance in vivo through the evolution of drug resistance, rather than through clone replacement. We hypothesize that carbapenem resistance in S. marcescens was due to certain clonal types with a distinct mechanism.

Pathogenic germline variants in non-BRCA1/2 homologous recombination genes in ovarian cancer: Analysis of tumor phenotype and survival

OBJECTIVE

To define molecular features of ovarian cancer (OC) with germline pathogenic variants (PVs) in non-BRCA homologous recombination (HR) genes and analyze survival compared to BRCA1/2 and wildtype (WT) OC.

METHODS

We included patients with OC undergoing tumor-normal sequencing (MSK-IMPACT) from 07/01/2015-12/31/2020, including germline assessment of BRCA1/2 and other HR genes ATM, BARD1, BRIP1, FANCA, FANCC, NBN, PALB2, RAD50, RAD51B, RAD51C, and RAD51D. Biallelic inactivation was assessed within tumors. Progression-free (PFS) and overall survival (OS) were calculated from pathologic diagnosis using the Kaplan-Meier method with left truncation. Whole-exome sequencing (WES) was performed in a subset.

RESULTS

Of 882 patients with OC, 56 (6.3%) had germline PVs in non-BRCA HR genes; 95 (11%) had BRCA1-associated OC (58 germline, 37 somatic); and 59 (6.7%) had BRCA2-associated OC (40 germline, 19 somatic). High rates of biallelic alterations were observed among germline PVs in BRIP1 (11/13), PALB2 (3/4), RAD51B (3/4), RAD51C (3/4), and RAD51D (8/10). In cases with WES (27/35), there was higher tumor mutational burden (TMB; median 2.5 [1.1-6.0] vs. 1.2 mut/Mb [0.6-2.6]) and enrichment of HR-deficient (HRD) mutational signatures in tumors associated with germline PALB2 and RAD51B/C/D compared with BRIP1 PVs (p < 0.01). Other features of HRD, including telomeric-allelic imbalance (TAI) and large-scale state transitions (LSTs), were similar. Although there was heterogeneity in PFS/OS by gene group, only BRCA1/2-associated OC had improved survival compared to WT OC (p < 0.01).

CONCLUSIONS

OCs associated with germline PVs in non-BRCA HR genes represent a heterogenous group, with PALB2 and RAD51B/C/D associated with an HRD phenotype.

Probability of outbreaks and cross-border dissemination of the emerging pathogen: a genomic survey of Elizabethkingia meningoseptica

IMPORTANCE

Elizabethkingia meningoseptica is an emerging infectious agent associated with life-threatening infections in immunocompromised individuals. However, there are limited data available on the genomic features of E. meningoseptica. This study aims to characterize the geographical distribution, phylogenetic evolution, pathogenesis, and transmission of this bacterium. A systematic analysis of the E. meningoseptica genome revealed that a common ancestor of this bacterium existed 90 years ago. The evolutionary history showed no significant relationship with the sample source, origin, or region, despite the presence of genetic diversity. Whole genome sequencing data also demonstrated that E. meningoseptica bacteria possess inherent resistance and pathogenicity, enabling them to spread within the same hospital and even across borders. This study highlights the potential for E. meningoseptica to cause severe nosocomial outbreaks and horizontal transmission between countries worldwide. The available evidence is crucial for the development of evidence-based public health policies to prevent global outbreaks caused by emerging pathogens.

Comparison of the inoculum effect of in vitro antibacterial activity of Imipenem/relebactam and Ceftazidime/avibactam against ESBL-, KPC- and AmpC-producing Escherichia coli and Klebsiella pneumoniae

OBJECTIVE

To evaluate effect of inoculum size of extended-spectrum β-Lactamase (ESBL)-producing-, AmpC-producing-, and KPC-producing Escherichia coli and Klebsiella pneumoniae on the in vitro antibacterial effects of imipenem/relebactam (IMR) and ceftazidime/avibactam (CZA).

METHODS

We compared the impact of inoculum size on IMR and CZA of sixteen clinical isolates and three standard isolates through antimicrobial susceptibility tests, time-kill assays and in vitro PK/PD studies.

RESULTS

When inoculum size increased from 105 to 107 CFU/mL, an inoculum effect was observed for 26.3% (5/19) and 52.6% (10/19) of IMR and CZA, respectively; time-kill assays revealed that the concentration of CZA increased from ≥ 4 × MIC to 16 × MIC to reach 99.9% killing rate against K. pneumoniae ATCC-BAA 1705 (KPC-2-, OXA-9- and SHV-182-producing) and 60,700 (SHV-27- and DHA-1-producing). While for IMR, a concentration from 1 × MIC to 4 × MIC killed 99.9% of the four strains. When the inoculum size increased to 109 CFU/mL, neither IMR nor CZA showed a detectable antibacterial effect, even at a high concentration. An in vitro PK/PD study revealed a clear bactericidal effect when IMR administered as 1.25 g q6h when inoculum size increased.

CONCLUSION

An inoculum effect on CZA was observed more frequent than that on IMR. Among the β-lactamase-producing strains, the inoculum effect was most common for SHV-producing and KPC-producing strains.

Comparative analysis of genomic characteristics, virulence and fitness of community-associated Staphylococcus aureus ST121 clone causing fatal diseases in China and other CA-MRSA clones

The increasing rate of community-associated Staphylococcus aureus (CA-SA) worldwide has aroused global public concern for decades. Although ST121 clone is one of the prevalent CA-SA in China, there is still limited knowledge about it. In this study, we conducted a genomic analysis of 28 CA-SA ST121 isolates from severe bloodstream infection cases and 175 ST121 isolates from the public database. Phylogenetic analysis revealed the consistency and the complexity of global ST121 lineages, and suggested potential cross-country even cross-continental transmission of ST121 isolates. By investigating the virulence and fitness between ST121-CA-methicillin-resistant SA (CA-MRSA) and other CA-MRSA clones, we found that ST121-MRSA exhibits virulence comparable to the highly virulent USA300 clone, exceeding that of the predominant CA-MRSA lineage ST59 in China and the other American CA-MRSA clone MW2. Notably, based on analyses of virulence genes, eta, etb, edin-C and egc were only found in ST121, suggesting that the high virulence of ST121 may be attributed to the combination of these virulence factors encoded by mobile genetic elements. However, results of experiments in mice nasal and human alveolar epithelial cells showed that the colonization capacity of ST121 is much lower than that of other clones. Moreover, ST121-MRSA displayed much lower acid tolerance, suggesting that ST121-MRSA may not have such capacity to achieve the epidemiological success of other CA-MRSA clones and become the dominant lineage. Our findings expand current understanding of the epidemiology and pathogenicity of the hypervirulent ST121 clone, and highlight the importance of colonization capacity and environmental adaption in MRSA epidemiological success.

A comprehensive point prevalence survey of the quality and quantity of antimicrobial use in Chinese general hospitals and clinical specialties

Antimicrobial resistance (AMR) is a serious, worldwide public health crisis. Surveillance of antimicrobial use forms part of an essential strategy to contain AMR. We aimed to conduct a national point prevalence survey (PPS) on antimicrobial use, and to compare this data with similar international surveillance programs to provide a reference for future AMR strategy development in China. Twenty general hospitals encompassing 10,881 beds and 10,209 inpatients around the country participated the survey using a standardized protocol, at 8am of someday from October 10th to November 31st, 2019. Of the patients, 37.00% (3777/10209) received antimicrobial agents, 31.30% (1630/5208) had surgical operations, and 76.63% (1249/1630) received prophylactic antibiotic. The prevalence of antimicrobial use in medical, surgical, and intensive care units (ICU) patients was 38.84% (1712/4408), 32.07% (1670/5208), and 66.61% (395/593), respectively. Of prescriptions, 5.79% (356/6151) were made in the absence of indication. The intensity of antimicrobial use was 61.25 DDDs/100 patient days, while the intensity of use in internal medicine, surgery, and ICU were 67.79, 45.81, 124.45 DDDs/100 patient days, respectively. Only 11.62% (715/6151) of prescriptions had a reason described in the patient record. Furthermore, 8.44% (210/2487), 14.19% (424/2989), and 12% (81/675) of the prescriptions in internal medicine, surgery, and ICU had a recorded indication, respectively. The review and stop date recorded for antimicrobial therapy was 43.73% (1976/4518). Of the patients, 38.07% (1438/3777) received combination therapy. The classes of antimicrobials prescribed were limited, and the proportion of prescriptions encompassed by the top 20 antimicrobial agents was 75.06% (4617/6151). The prevalence of antimicrobial use in China is close to that of Sweden, the UK, and Canada, but lower than that in India, and higher than that in Switzerland. The data described in this report indicate that the quality of antimicrobial prescriptions requires improvement in China. Further, hospitals should implement professional interventions to improve the rational use of antimicrobials.

An integrated nationwide genomics study reveals transmission modes of typhoid fever in China

IMPORTANCE

Typhoid fever is a life-threatening disease caused by Salmonella enterica serovar Typhi, resulting in a significant disease burden across developing countries. Historically, China was very much close to the global epicenter of typhoid, but the role of typhoid transmission within China and among epicenter remains overlooked in previous investigations. By using newly produced genomics on a national scale, we clarify the complex local and global transmission history of such a notorious disease agent in China spanning the most recent five decades, which largely undermines the global public health network.

Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or "golden rules," for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice.

Clinical, biological and genome-wide comparison of carbapenem-resistant Klebsiella pneumoniae with susceptibility transformation to polymyxin B during therapy

OBJECTIVES

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is a major clinical concern, and polymyxin B (PMB) is a 'last resort' antibiotic for its treatment. Understanding the effects of drug susceptibility transformation in CRKP-infected patients undergoing PMB treatment would be beneficial to optimize PMB treatment strategies.

METHODS

We retrospectively collected data from patients infected with CRKP and treated with PMB from January 2018 to December 2020. CRKPs were collected before and after PMB therapy, and patients were classified into the 'transformation' group (TG) and 'non-transformation' group (NTG) by the shift of susceptibility to PMB. We compared clinical characteristics between these groups, and further analysed the phenotypic and genome variation of CRKP after PMB susceptibility transformation.

RESULTS

A total of 160 patients (37 in the TG and 123 in the NTG) were included in this study. The duration of PMB treatment before PMB-resistant K. pneumoniae (PRKP) appearance in TG was even longer than the whole duration of PMB treatment in NTG (8 [8] vs. 7 [6] days; p 0.0496). Compared with isogenic PMB-susceptible K. pneumoniae (PSKP), most PRKP strains had missense mutations in mgrB (12 isolates), yciC (10 isolates) and pmrB (7 isolates). The competition index of 82.4% (28/34) of PRKP/PSKP pairs was <67.6% (23/34), and 73.5% (25/34) of PRKP strains showed a higher 7-day lethality in Galleria mellonella and a greater ability to resist complement-dependent killing than their corresponding PSKP, respectively.

CONCLUSION

Low dose with longer PMB treatment durations may be associated with the emergence of polymyxin resistance. The evolution of PRKP is predominantly mediated by an accumulation of mutations, including those in mgrB, yciC, and pmrB. Lastly, PRKP exhibited reduced growth and increased virulence compared with parental PSKP.

The Sex Ratio Indicates the Conclusion and Onset of Population Cycles in the Beet Webworm Loxostege sticticalis L. (Lepidoptera: Pyralidae)

Beet webworms, Loxostege sticticalis L. (Lepidoptera: Pyralidae), are one of the most destructive pest insects in northern China, and their populations outbreak periodically. Developing an indicator that defines the ending and beginning of the occurrence period cycle is urgent for the population forecast and theoretical study. The sex ratio can be a primary pathway through which species regulate population size. We measured the maximum mating potential of both females and males and the population net reproductive rate under different sex ratios (e.g., 3:1, 2:1, 1:1, 1:2, 1:3). The maximum mating frequency of males was 2.91 times that of females. The progeny contribution per mating decreased with increased mating times in males. The variation in population net reproductive rate affected by the sex ratio fits the parabolic curve analysis and peaked at 1.82 for females vs. males. Our results illustrate the quantitative connection phenomenon shown by the historical data: population outbreaks occur at a sex ratio of two or more and collapse at a sex rate lower than one. Simultaneously, the sex ratio may be utilized as a definite indicator for the beginning and end of the future occurrence cycle in the beet webworm.

Novel SCCmec variants in clonal complex 398 and lineage-specific pseudo-SCCmec identified in ST88 MRSA from invasive bloodstream infections in China

BACKGROUND

Methicillin resistance in Staphylococcus aureus is primarily due to the mecA gene found in highly diverse staphylococcal cassette chromosome mec (SCCmec) elements, with an increasing number of variants being continually discovered.

OBJECTIVES

To characterize two novel SCCmec variants identified in clonal complex (CC) 398 strains and lineage-specific pseudo-SCCmec elements in the ST88 clone.

METHODS

WGS and comparative genomic analysis were used to elucidate the SCCmec element diversity of representative isolates.

RESULTS

The non-typeable 47 kb SCCmec found in the CC398 strain SKLX55795 represents a novel subtype of XIV, showing significant differences in structural organization and genetic content within the joining regions compared with the XIV element from the prototype strain SC792. This unique subtype comprised remnants from various mobile genetic elements that encode antimicrobial resistance genes, ultimately forming a large MDR region. Genome analysis of CC398 strain SKLX61416 revealed the presence of a novel 50 kb composite SCCmec with two distinct domains, carrying the ccr gene complexes 5/8 and containing genes for the detoxification of arsenic and sulphide. Further sequence analysis disclosed that 44.23% (23/52) of ST88 strains in our collection carried a lineage-specific pseudo-SCCmec, termed ΨSCCmecST88. This ΨSCCmecST88 harboured the mec gene complex C2, along with a series of genes associated with heavy metal resistance, but lacked an approximately 28 kb region encompassing the ccr gene complex.

CONCLUSIONS

Our findings provide evidence for the ongoing evolution of SCCmec elements within the CC398 and ST88 clones, underscoring the need for further surveillance to understand the biological significance of these elements.

Notes on two species of Massuria Thorell, 1887 (Arachnida, Araneae, Thomisidae) from China with description of a new species

Two species assigned to Massuria Thorell, 1887 are reviewed. The female of Massuriabandian Tang & Li, 2010 is described for the first time from Jianfengling National Natural Reserve, Hainan Province, China. The species Diaeasimplex Xu, Han & Li, 2008 is described as a synonym of Massuriabellula Xu, Han & Li, 2008 based on female and male specimens from Guangdong Province, China. Massuriaminsp. nov. described as a new species (female, Fujian Province, China). Detailed illustrations and a distribution map are provided for these three species of Massuria.

ACORN (A Clinically-Oriented Antimicrobial Resistance Surveillance Network) II: protocol for case based antimicrobial resistance surveillance

Background: Antimicrobial resistance surveillance is essential for empiric antibiotic prescribing, infection prevention and control policies and to drive novel antibiotic discovery. However, most existing surveillance systems are isolate-based without supporting patient-based clinical data, and not widely implemented especially in low- and middle-income countries (LMICs). Methods: A Clinically-Oriented Antimicrobial Resistance Surveillance Network (ACORN) II is a large-scale multicentre protocol which builds on the WHO Global Antimicrobial Resistance and Use Surveillance System to estimate syndromic and pathogen outcomes along with associated health economic costs. ACORN-healthcare associated infection (ACORN-HAI) is an extension study which focuses on healthcare-associated bloodstream infections and ventilator-associated pneumonia. Our main aim is to implement an efficient clinically-oriented antimicrobial resistance surveillance system, which can be incorporated as part of routine workflow in hospitals in LMICs. These surveillance systems include hospitalised patients of any age with clinically compatible acute community-acquired or healthcare-associated bacterial infection syndromes, and who were prescribed parenteral antibiotics. Diagnostic stewardship activities will be implemented to optimise microbiology culture specimen collection practices. Basic patient characteristics, clinician diagnosis, empiric treatment, infection severity and risk factors for HAI are recorded on enrolment and during 28-day follow-up. An R Shiny application can be used offline and online for merging clinical and microbiology data, and generating collated reports to inform local antibiotic stewardship and infection control policies. Discussion: ACORN II is a comprehensive antimicrobial resistance surveillance activity which advocates pragmatic implementation and prioritises improving local diagnostic and antibiotic prescribing practices through patient-centred data collection. These data can be rapidly communicated to local physicians and infection prevention and control teams. Relative ease of data collection promotes sustainability and maximises participation and scalability. With ACORN-HAI as an example, ACORN II has the capacity to accommodate extensions to investigate further specific questions of interest.

Manipulating the Alkyl Chains of Naphthodithiophene Imide-Based Polymers to Concurrently Boost the Efficiency and Stability of Organic Solar Cells

Morphology instability holds the major responsibility for efficiency degradation of organic solar cells (OSCs). However, how to develop polymer donors simultaneously with high efficiency and excellent morphology stability remains challenging. Herein, we reported naphtho[2,1-b:3,4-b']dithiophene-5,6-imide (NDTI)-based new polymers PNDT1 and PNDT2. The alkyl chain engineering leads to high crystallinity, high hole mobility (>10-3 cm2 V-1 S-1), and nanofibrous film morphology, which enable PNDT2 to exhibit an efficiency of 18.13% and a remarkable FF value of 0.80. Moreover, the NDTIs have short π-π stacking and abundant short interactions, and their polymers exhibit superior morphological stability. Therefore, the PNDT2-based OSCs exhibit much better device stability than that of PNDT1, PAB-α, and benchmark polymers PM6 and D18. This work suggests the great importance of the large conjugated backbone of the monomer and alkyl chain engineering to develop high-performance and morphology-stable polymers for OSCs.

Association between particulate matter (PM)2·5 air pollution and clinical antibiotic resistance: a global analysis

BACKGROUND

Antibiotic resistance is an increasing global issue, causing millions of deaths worldwide every year. Particulate matter (PM)2·5 has diverse elements of antibiotic resistance that increase its spread after inhalation. However, understanding of the contribution of PM2·5 to global antibiotic resistance is poor. Through univariate and multivariable analysis, we aimed to present the first global estimates of antibiotic resistance and burden of premature deaths attributable to antibiotic resistance resulting from PM2·5 pollution.

METHODS

For this global analysis, data on multiple potential predictors (ie, air pollution, antibiotic use, sanitation services, economics, health expenditure, population, education, climate, year, and region) were collected in 116 countries from 2000 to 2018 to estimate the effect of PM2·5 on antibiotic resistance via univariate and multivariable analysis. Data were obtained from ResistanceMap, European Centre for Disease Prevention and Control Surveillance Atlas (antimicrobial-resistance sources), and PLISA Health Information Platform for the Americas. Future global aggregate antibiotic resistance and premature mortality trends derived from PM2·5 in different scenarios (eg, 50% reduced antibiotic use or PM2·5 controlled to 5 μg/m3) were projected until 2050.

FINDINGS

The final dataset included more than 11·5 million tested isolates. Raw antibiotic-resistance data included nine pathogens and 43 types of antibiotic agents. Significant correlations between PM2·5 and antibiotic resistance were consistent globally in most antibiotic-resistant bacteria (R2=0·42-0·76, p<0·0001), and correlations have strengthened over time. Antibiotic resistance derived from PM2·5 caused an estimated 0·48 (95% CI 0·34-0·60) million premature deaths and 18·2 (13·4-23·0) million years of life lost in 2018 worldwide, corresponding to an annual welfare loss of US$395 (290-500) billion due to premature deaths. The 5 μg/m3 target of concentration of PM2·5 in the air quality guidelines set by WHO, if reached in 2050, was estimated to reduce antibiotic resistance by 16·8% (95% CI 15·3-18·3) and avoid 23·4% (21·2-25·6) of premature deaths attributable to antibiotic resistance, equivalent to a saving of $640 (580-671) billion.

INTERPRETATION

This analysis is the first to describe the association between PM2·5 and clinical antibiotic resistance globally. Results provide new pathways for antibiotic-resistance control from an environmental perspective.

FUNDING

National Natural Science Foundation of China, Fundamental Research Funds for the Central Universities, Zhejiang University Global Partnership Fund, and China Postdoctoral Science Foundation.

[Association between cardiometabolic diseases and quality of life and the mediation effect of perceived stress]

Objective: To explore the association between cardiometabolic diseases (CMD) and quality of life, the association between CMD and perceived stress, and the mediation effect of perceived stress on the association between CMD and quality of life, and to provide evidence for the prevention and treatment of CMD and the improvement of quality of life in these patients. Methods: This is a cross-sectional study. Data were collected by the employees' physical examination of a company in Xi'an in 2021. Multiple linear regression models were used to analyze the association between the status of CMD (divided into three categories: no CMD, presence of one kind of CMD, and with≥2 kinds of CMD (≥2 kinds of CMD were defined as cardiometabolic multimorbidity (CMM)), quality of life, and perceived stress. Mediation analysis with a multi-categorical independent variable was conducted to determine the mediation effect of perceived stress on the association between CMD and quality of life. Results: Among all 4 272 participants, 1 457 (34.1%) participants had one kind of CMD and 677 (15.8%) participants had CMM. The average scores for quality of life and perceived stress were (57.5±15.7) and (16.9±7.9), respectively. Compared with participants without CMD, after adjusting for demographic and lifestyle factors, no statistically significant associations were observed between one kind of CMD and perceived stress or quality of life (both P>0.05). Perceived stress did not mediate the association between one kind of CMD and quality of life. However, participants with CMM had lower quality of life and higher perceived stress than participants without CMD. The relative total effect coefficient c (95%CI) and the relative direct effect coefficient c' (95%CI) between CMM and quality of life were -3.71 (-5.04--2.37) and -2.52 (-3.81--1.24) (both P<0.05), respectively. The relative indirect effect coefficient a₂b (95%CI) of perceived stress on the association between CMM and quality of life was -1.18 (-1.62--0.77) (P<0.05). The mediation effect size was 31.8%. Conclusions: CMM is negatively associated with quality of life and positively associated with perceived stress. Perceived stress partially mediates the association between CMM and quality of life. Our results suggest that, in addition to preventing and treating CMM actively, efforts should be taken to relieve the perceived stress of people with CMM to improve their quality of life.

Mechanochemistry toward Organic "Salt" via Integer-Charge-Transfer Cocrystal Strategy for Rapid, Efficient, and Scalable Near-Infrared Photothermal Conversion

Inspired by the concept of ionic charge-transfer complexes for the Mott insulator, integer-charge-transfer (integer-CT) cocrystals are designed for NIR photo-thermal conversion (PTC). With amino-styryl-pyridinium dyes and F4TCNQ (7,7',8,8'-Tetracyano-2,3,5,6-tetrafluoroquinodimethane) serving as donor/acceptor (D/A) units, integer-CT cocrystals, including amorphous stacking "salt" and segregated stacking "ionic crystal", are synthesized by mechanochemistry and solution method, respectively. Surprisingly, the integer-CT cocrystals are self-assembled only through multiple D-A hydrogen bonds (C-H⋅⋅⋅X (X=N, F)). Strong charge-transfer interactions in cocrystals contribute to the strong light-harvesting ability at 200-1500 nm. Under 808 nm laser illumination, both the "salt" and "ionic crystal" display excellent PTC efficiency beneficial from ultrafast (∼2 ps) nonradiative decay of excited states. Thus integer-CT cocrystals are potential candidates for rapid, efficient, and scalable PTC platforms. Especially amorphous "salt" with good photo/thermal stability is highly desirable in practical large-scale solar-harvesting/conversion applications in water environment. This work verifies the validity of the integer-CT cocrystal strategy, and charts a promising path to synthesize amorphous PTC materials by mechanochemical method in one-step.

[Immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine in people aged 60 years and above]

Objective: To evaluate the immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine (PPV23) in elderly people aged ≥60 years. Methods: The elderly aged ≥60 years with 1 dose of PPV23 vaccination were selected as revaccination group and those without history of pneumococcal vaccine immunization were selected as the first vaccination group. One dose of PPV23 was administered to both groups, and the first blood samples were collected before vaccination while the second blood samples were collected on day 28-40 after vaccination. ELISA was used to detect the concentrations of anti-specific serotype Streptococcus pneumoniae podocyte polysaccharide immunoglobulin G, and the safety of the vaccination was evaluated after 30 days. Results: The geometric mean concentration (GMC) of antibody to 23 serotypes before the vaccination (0.73-13.73 μg/ml) was higher in revaccination group than in the first vaccination group (0.39-7.53 μg/ml), the GMC after the vaccination (1.42-31.65 μg/ml) was higher than that before the vaccination (0.73-13.73 μg/ml) in the revaccination group, and the GMC after the vaccination (1.62-43.76 μg/ml) was higher than that before the vaccination (0.39-7.53 μg/ml) in the first vaccination group; the geometric mean growth multiple in revaccination group (2.16-3.60) was lower than that in the first vaccination group (3.86-16.13); The mean 2-fold antibody growth rate was lower in revaccination group (53.68%, 95%CI: 52.30%-55.06%) than in the first vaccination group (93.16%, 95%CI: 92.18%- 94.15%), all differences were significant (P<0.001). After the vaccination, 13 serotypes of GMC were higher in the first vaccination group than in revaccination group (P<0.001), the differences were not significant for 10 serotypes of GMC (P>0.05). The incidence of local adverse reaction was 19.20% and 13.27% in revaccination group and the first vaccination group, respectively (P=0.174). Conclusions: The antibody level in ≥60 years people who received one dose of PPV23 after a 5-year interval was still higher than that in unvaccinated people. The antibody level decreased after 5 years of the first vaccination, and the antibody level could be rapidly increased by one more dose vaccination, but the overall immune response was lower than that of the first vaccination; revaccination with PPV23 has a good safety.

Mechanochemistry toward Organic "Salt" via Integer-Charge-Transfer Cocrystal Strategy for Rapid, Efficient, and Scalable Near-Infrared Photothermal Conversion

Invited for this month's cover is the group of Shun-Li Chen and Ming-De Li at the Shantou University. The image shows that one electron can be transferred easily from donor to acceptor unit to obtain integer-charge-transfer cocrystals for realizing high-efficient solar-harvesting and photothermal conversion. The Research Article itself is available at 10.1002/cssc.202300644.

A new species of Mallinella Strand, 1906 (Araneae, Zodariidae) from South China

Background

Only one zodariid species, Storenomorphalushanensis Yu & Chen, 2009 was found from Jiangxi Province. No other Mallinella species have been recorded from this Province.

New information

A new species, Mallinellashahu sp. n. is described from Jiangxi Province, China. Morphological illustrations, living photos and distribution map are given.

Improving Blood Culture Quality with a Medical Staff Educational Program: A Prospective Cohort Study

Purpose

Blood cultures (BCs) are essential laboratory tests for diagnosing blood stream infections. BC diagnostic improvement depends on several factors during the preanalytical phase outside of innovative technologies. In order to evaluate the impact of an educational program on BC quality improvement, a total of 11 hospitals across China were included from June 1st 2020 to January 31st 2021.

Methods

Each hospital recruited 3 to 4 wards to participate. The project was divided into three different periods, pre-implementation (baseline), implementation (educational activities administered to the medical staff) and post-implementation (experimental group). The educational program was led by hospital microbiologists and included professional presentations, morning meetings, academic salons, seminars, posters and procedural feedback.

Results

The total number of valid BC case report forms was 6299, including 2739 sets during the pre-implementation period and 3560 sets during the post-implementation period. Compared with the pre-implementation period, some indicators, such as the proportion of patients who had 2 sets or more, volume of blood cultured, and BC sets per 1000 patient days, were improved in the post-implementation period (61.2% vs 49.8%, 18.56 vs 16.09 sets, and 8.0 vs 9.0mL). While BC positivity and contamination rates did not change following the educational intervention (10.44% vs 11.97%, 1.86% vs 1.94%, respectively), the proportion of coagulase negative staphylococci-positive samples decreased in BSI patients (6.87% vs 4.28%).

Conclusion

Therefore, medical staff education can improve BC quality, especially increasing volume of blood cultured as the most important variable to determine BC positivity, which may lead to improved BSI diagnosis.

Mechanisms of ceftazidime/avibactam resistance in drug-naïve bacteremic Enterobacteriales strains without metallo-beta-lactamase production: associated with ceftazidime impedance

To investigate ceftazidime/avibactam (CZA) resistance characteristics and mechanisms of bacteremic Enterobacteriales strains not previously treated with CZA, 9,708 strains were collected from 43 hospitals in 18 provinces across China from January 2019 to June 2020. Of them, MIC values of CZA in 165 (1.70%) strains were ≥8/4 mg/L. Ten (6.06%) CZA-resistant strains without metallo-β-lactamase production were obtained from the individuals without prior exposure to CZA, including six Escherichia coli (E. coli) isolates, three Klebsiella pneumoniae (K. pneumoniae), and one Enterobacter cloacae (E. cloacae). Whole-genome sequencing revealed that ECB88611, ECB142593 and ECB144539 had encoded disrupted OmpF loss of function. OmpF of ECB126041 had a 2_9 MKRNILAV deletion; OmpK35 of three K. pneumoniae harbored amino acids fragment deletion from position 1 to 38; ELB117287 also had encoded disrupted OmpF. The G132D amino acid substitution of OmpC of ECB88611, ECB142593 and ECB144539, and the 134_135GD insertion of OmpK36 of three K. pneumoniae isolates were predicted to alter ceftazidime permeability. 333_334 YRIK or YRIN insertions occurred in PBP3 of six E. coli isolates. The relative expression of bla_KPC-2 in KPB125108 was 4.527 ± 0.2166 times and acrF in six E. coli isolates was 2-3 times higher than that of control strain. The addition of phenylalanine-arginine-β-naphthylamine at 100 mg/L, significantly decreased the MIC values of CZA against nine strains. In conclusion, antimicrobial resistance mechanisms in ten isolates, included increased expression of bla_KPC-2, non-functional OMPs, upregulation of efflux pump activity, and variants of PBP3. Most of these mechanisms affected antimicrobial activity of CZA by impeding ceftazidime.

A point mutation in recC associated with subclonal replacement of carbapenem-resistant Klebsiella pneumoniae ST11 in China

Adaptation to selective pressures is crucial for clinically important pathogens to establish epidemics, but the underlying evolutionary drivers remain poorly understood. The current epidemic of carbapenem-resistant Klebsiella pneumoniae (CRKP) poses a significant threat to public health. In this study we analyzed the genome sequences of 794 CRKP bloodstream isolates collected in 40 hospitals in China between 2014 and 2019. We uncovered a subclonal replacement in the predominant clone ST11, where the previously prevalent subclone OL101:KL47 was replaced by O2v1:KL64 over time in a stepwise manner. O2v1:KL64 carried a higher load of mobile genetic elements, and a point mutation exclusively detected in the recC of O2v1:KL64 significantly promotes recombination proficiency. The epidemic success of O2v1:KL64 was further associated with a hypervirulent sublineage with enhanced resistance to phagocytosis, sulfamethoxazole-trimethoprim, and tetracycline. The phenotypic alterations were linked to the overrepresentation of hypervirulence determinants and antibiotic genes conferred by the acquisition of an rmpA-positive pLVPK-like virulence plasmid and an IncFII-type multidrug-resistant plasmid, respectively. The dissemination of the sublineage was further promoted by more frequent inter-hospital transmission. The results collectively demonstrate that the expansion of O2v1:KL64 is correlated to a repertoire of genomic alterations convergent in a subpopulation with evolutionary advantages.

Antimicrobial use, healthcare-associated infections, and bacterial resistance in general hospitals in China: the first national pilot point prevalence survey report

The purpose of this study is to implement point prevalence survey (PPS), assess antimicrobial prescribing and resistance in general hospitals and clinical specialties in China, and compare them with similar data from other parts of the world. Twenty general hospitals in China were surveyed in October or November, 2019. A standardized surveillance protocol was used to collect data on patient demographics, diagnosis of infection, the prevalence and intensity of antimicrobial use, prescribing quality, bacterium type and resistance spectrum, and the prevalence and type of healthcare-associated infections (HAIs). Overall, 10,881 beds and 10,209 inpatients were investigated. The overall prevalence of antibiotic use was 37.00%, the use of antibiotic prophylaxis in surgical patients was high (74.97%). The intensity of antimicrobial use was 61.25 DDDs/100 patient days. Only 11.62% of antimicrobial prescriptions recorded the reason for prescribing. Intravenous or combination treatments comprised 92.02% and 38.07%, respectively, and only 30.65% of prescriptions referred to a microbiological or biomarker tests. The incidence of HAIs in all patients was 3.79%. The main associated factors for HAIs included more frequent invasive procedures (27.34%), longer hospital stay (> 1-week stay accounting for 51.47%), and low use of alcohol hand rubs (only 29.79% placed it bedside). Most of the resistant bacteria declined; only carbapenem-resistant Enterobacter is higher than previously reported. The prevalence of antibiotic use in general hospitals fell significantly, the overall bacterial resistance declined, and the incidence of HAI was low. However, the low quality of antimicrobial use requires urgent attention.

Identification and Characterization of OXA-232-Producing Sequence Type 231 Multidrug Resistant Klebsiella pneumoniae Strains Causing Bloodstream Infections in China

Klebsiella pneumoniae, a notorious pathogen for opportunistic health care-associated infections, represents increasing multidrug resistance, particularly to carbapenems. OXA-232 carbapenemase, as a variant of OXA-48, has been increasingly reported worldwide. ST231, an epidemic, multidrug resistant (MDR) K. pneumoniae clone in south and southeast Asia, has been found in other regions, including Europe. In the study, five OXA-232 carbapenemase-producing Klebsiella pneumoniae isolates, four of which belong to sequence type 231 (ST231) and one of which belongs to ST15, were isolated from two hospitals in China. All isolates displayed a MDR phenotype, being susceptible to only polymyxin B and colistin, and the blaOXA-232 gene was located on a ColKP3-type nonconjugative plasmid of 6.1 kb. A phylogenetic analysis of the global ST231 K. pneumoniae isolates (n = 231) suggested that the four ST231 isolates from this study gathered with strains from south Asia (especially India), indicating that the emerging Chinese ST231 clone was more closely related to south Asia isolates and might have spread from south Asia, where ST231 was a successful epidemic clone. Virulence assays suggested that the four ST231 strains were not highly virulent, as they displayed significantly lower virulence potential, compared with a ST23 K1 hypervirulent isolate in a G. mellonella infection and in mouse intraperitoneal infection models, although three ST231 strains harbored a plasmid-borne aerobactin-encoding iuc gene cluster. This is the first report of ST231 K. pneumoniae clinical strains bearing blaOXA-232 in China, and it highlights the emergence of the ST231 clone causing bloodstream infections in a health care setting as well as calls attention to the transmission of this emerging clone in China. IMPORTANCE OXA-232 carbapenemase, being a vital resistance mechanism against carbapenems, has recently been increasingly reported. In China, the identified OXA-232-producing K. pneumoniae isolates almost belonged to ST15 and were not hypervirulent, despite harboring a virulence plasmid. Here, we report the first occurrence in China of a MDR OXA-232-producing K. pneumoniae ST231 clone that is an epidemic ST type in south and southeast Asia. A phylogenetic analysis indicated that this emerging Chinese ST231 clone was more closely related to Indian isolates. The occurrence of this clone may have been driven through the transnational importation of Indian ST231 K. pneumoniae clones. Moreover, this study is the first to assess the virulence potential of ST231 clones that have never been estimated in previous studies. While the high burden of MDR K. pneumoniae is concerning, genomic surveillance can shed light on the transmission chains of novel MDR clones, and active surveillance should be enforced to restrict the spread of MDR isolates.

A Multifluorination Strategy Toward Wide Bandgap Polymers for Highly Efficient Organic Solar Cells

Creating new electron-deficient unit is highly demanded to develop high-performance polymer donors for non-fullerene organic solar cells (OSCs). Herein, we reported a multifluorinated unit 4,5,6,7-tetrafluoronaphtho[2,1-b : 3,4-b']dithio-phene (FNT) and its polymers PFNT-F and PFNT-Cl. The advantages of multifluorination: (1) it enables the polymers to exhibit low-lying HOMO (≈-5.5 eV) and wide band gap (≈2.0 eV); (2) the short interactions (F⋅⋅⋅H, F⋅⋅⋅F) endow the polymers with properties of high film crystallinity and efficient hole transport; (3) well miscibility with NFAs that leads to a more well-defined nanofibrous morphology and face-on orientation in the blend films. Therefore, the PFNT-F/Cl : N3 based OSCs exhibit impressive FF values of 0.80, and remarkable PCEs of 17.53 % and 18.10 %, which make them ranked the best donor materials in OSCs. This work offers new insights into the rational design of high-performance polymers by multifluorination strategy.

Building a cobaloxime-based metal-organic framework for photocatalytic aerobic oxidation of arylboronic acids to phenols

Herein, the design and synthesis of an unprecedented cobaloxime-based zirconium metal-organic framework (Zr-TCPCo) with an she net is reported. This heterogeneous material as a photocatalyst exhibits excellent catalytic activity for aerobic oxidation of arylboronic acids to phenols. Recycling experiments demonstrate the stability and reusability of Zr-TCPCo as a robust catalyst.

Protective efficacy of statins in patients with Klebsiella pneumoniae bloodstream infection

Background

Patients with bloodstream infection of Klebsiella pneumoniae (BSI-KP) have a high risk of death and septic shock. This study aims to identify the risk factors for mortality and severity in patients of BSI-KP.

Methods

Data of BSI-KP patients were extracted from the MIMIC IV (Medical Information Mart for Intensive Care IV) database, and patients infected with only K. pneumoniae in blood were included in this study. The risk factors of 28-day mortality and septic shock in BSI-KP patients were analyzed, respectively.

Results

A total of 279 patients enrolled and the all-cause 28-day mortality rate was 11.8%. The use of statins (OR 0.220, 95% CI 0.060-0.801, p = 0.022) and quinolones (OR 0.356, 95% CI 0.143-0.887, p = 0.027) were both independent protective factors for death within 28 days, while the use of vasoactive drugs (OR 7.377, 95% CI 1.775-30.651, p = 0.006) was a risk factor. Besides, pulmonary disease (OR 2.348, 95% CI 1.126-4.897, p = 0.023), bleeding and coagulation disorders (OR 3.626, 95% CI 1.783-7.372, p < 0.001), respiratory failure (OR 2.823, 95% CI 0.178-6.767, p = 0.020) and kidney dysfunction (OR 2.450, 95% CI 1.189-5.047, p = 0.015) were independent risk factors for patients suffered from septic shock while hypertension was a protective one. The receiver operating characteristic (ROC) curves could well predict the risk of death within 28-day (area under ROC = 0.855, 95% CI = 0.796-0.914, p < 0.001) and septic shock (AUROC = 0.815, 95% CI = 0.755-0.874, p < 0.001) in patients with BSI-KP.

Conclusion

The use of statins could decrease the risk of 28-day mortality in patients of BSI-KP. The risk factor-based prediction model provided evidence for drug treatment in BSI-KP patients. Paying more attention to the strategy of drug treatment will be an optimal way to improve patient's outcome in clinical practice.

Prevalent Dominant Acinetobacter baumannii ST191/195/208 Strains in Bloodstream Infections Have High Drug Resistance and Mortality

Background

Different sequence types of Acinetobacter baumannii (AB) have their own epidemiological characteristics, drug resistance, and toxicity.

Methods

AB bloodstream infection (BSI) in the First Affiliated Hospital of Medical College of Zhejiang University from January 2012 to December 2017 were classified by multilocus sequence typing. Clinical data of patients were retrospectively analyzed, drug resistance and toxicity were respectively studied by drug sensitivity and complement killing tests.

Results

247 unduplicated AB strains were collected, and ST191/195/208, the main epidemic dominant strain, accounted for 70.9%. Patients with ST191/195/208 on infection had higher white blood cell (10.8 vs 8.9, p = 0.004), neutrophil% (89.5 vs 86.9, p = 0.005), neutrophil count (9.5 vs 7.1, p = 0.021), D-dimer (6.7 vs 3.8, p = 0.000), total bilirubin (27.0 vs 21.5, p = 0.038), pronatriuretic peptide (324 vs 164, p = 0.042), C-reactive protein (82.5 vs 56.3, p = 0.048), clinical pulmonary infection score (CPIS; 7.33 ± 2.30 vs 6.50 ± 2.72, p = 0.045), and acute physiology and chronic health evaluation-II (APACHE-II; 19.620 ± 5.1850 vs 17.648 ± 6.1251, p = 0.011). Patients with ST191/195/208 had more complications, including pulmonary infection (p = 0.041), septic shock (p = 0.009), and multiple organ failure (p = 0.019). Patients with ST191/195/208 had higher 3 day mortality (24.6% vs 13.9%, p = 0.043), 14 day mortality (46.8% vs 26.8%, p = 0.003), and 28 day mortality (55.0% vs 32.4%, p = 0.001). ST191/195/208 strains had higher drug resistance to most antibiotics, and higher survival rate at 90% normal serum concentration (p < 0.001).

Conclusion

ST191/195/208 strains predominate in the hospital and prevails in patients with severe infections with increased multidrug antimicrobial resistance and excessive mortality compared to any other AB stains.

Phenotypic and genomic comparison of dominant and nondominant sequence-type of Acinetobacter baumannii isolated in China

A. baumannii is a common clinical pathogen that often causes pneumonia and bloodstream infections in ICU patients. Sequence types (ST) are used to investigate the distribution and spread of A. baumannii. Biological characteristics such as virulence and resistance may play a role in A. baumannii becoming a specific dominant ST(DST,ST191, ST195 and ST208) strain. To characterize the biological, genetic, and transcriptomic differences between the DST and non-dominant ST(NST,ST462 and ST547,etc.) strains in A. baumannii, we performed several biological experiments and genetic, and transcriptomic analyses. The DST group displayed more resistance ability to desiccation, oxidation, multiple antibiotics, and complement killing than the NST group. However, the latter had higher biofilm formation ability than the former. The genomic analysis showed the DST group exhibited more capsule-related and aminoglycoside-resistant genes. Besides, GO analysis indicated that functions involved in lipid biosynthetic, transport, and the metabolic process were up-regulated in the DST group, while KEGG analysis manifested that the two-component system related to potassium ion transport and pili were down-regulated. In short, resistance to desiccation, oxidation, multiple antibiotics, and serum complement killing are important reasons for the formation of DST. Genes related to capsule synthesis and lipid biosynthesis and metabolism play an important role at the molecular level in the formation of DST.

Modulating Anthracene Excimer through Guest Engineering in Two-Dimensional Lead Bromide Hybrids

A full understanding of the excimer formation and structure-property relationship is essential to their development in organic electronics. Herein, we propose a template strategy for finely modulating the stacking configuration...

Cefepime, not Piperacillin/Tazobactam use, for empirical treatment of bloodstream infections caused by Enterobacter spp.: Results from a population pharmacokinetic/pharmacodynamic analysis

OBJECTIVE

There is a paucity of published data to evaluate the efficacy and safety of imipenem, cefepime and piperacillin/tazobactam dosing regimens against bloodstream infections caused by Klebsiella aerogenes (BSIs-Kae) and Enterobacter cloacae complex (BSIs-Ecc) in patients with various degrees of renal function.

METHODS

Pathogens were isolated from China's blood bacterial resistant investigation network. The dosing regimens of imipenem, cefepime and piperacillin were simulated with intermittent infusion and extended infusion. Monte Carlo simulation was performed to calculate the probability of target attainment and a cumulative fraction of response (CFR) against BSIs-Kae/Ecc.

RESULTS

In total, 203 BSIs-Kae, and 785 BSIs-Ecc were isolated from the surveillance network. Imipenem showed the highest in vitro activity against BSIs-Kae/Ecc, followed by cefepime (85%) and piperacillin/tazobactam (70-80%). The MIC₉₀ values of imipenem, cefepime and piperacillin/tazobactam aginst BSIs-Kae and BSIs-Ecc were 1/1 mg/L, 16/16 mg/L, and 64/128 mg/L, respectively. The simulation results showed imipenem achieved the highest CFRs in patients with normal or decreased renal function, with values of 91-99%, followed by FEP (88-96%), without risk of excessive dosing. However, the intermittent and extended dosing regimens of piperacillin/tazobactam were unlikely to provide adequate exposure for empirical management of BSIs-Kae/Ecc (CFRs, 50-80%), regardless of renal function. Besides, the traditional intermittent piperacillin/tazobactam dosing regimens were highly likely to contribute to suboptimal therapeutic exposure when MIC was close to clinical breakpoints.

CONCLUSIONS

Cefepime, not piperacillin/tazobactam, can be a reasonable carbapenem-sparing option in empirically treating BSIs-Kae/Ecc.

Two new thomisid species (Arachnida, Araneae, Thomisidae) from China and Vietnam, with the first descriptions of the males of Borboropactuslongidens Tang & Li, 2010 and Stephanopisxiangzhouica Liu, 2022

Collections of thomisid spiders by amateur and professional arachnologists in China have led to the discovery of some interesting crab spiders (Thomisidae). Two new species in two genera of thomisid spiders are described and illustrated with photographs and SEMs: Phartaxizang Liu & Yao, sp. nov. (♀) and Stephanopisqiong Liu & Yao, sp. nov. (♀). The previously unknown males of Borboropactuslongidens Tang & Li, 2010 and Stephanopisxiangzhouica Liu, 2022 were also collected and are described for the first time. The genus Borboropactus Simon, 1884 is reported for the first time from Vietnam. The new Stephanopis species is also recorded for only the second time from the Asian mainland. Distributions of all these species are mapped.

Small wards in the ICU: a favorable measure for controlling the transmission of carbapenem-resistant Klebsiella pneumoniae

PURPOSE

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the leading causes of healthcare-associated infections (HAIs) and is particularly pervasive in intensive care units (ICUs). This study takes ICU layout as the research object, and integrates clinical data and bacterial genome analysis to clarify the role of separate, small wards within the ICU in controlling the transmission of CRKP.

METHODS

This study prospectively observed the carriage and spread of CRKP from a long-term in-hospital patient (hereafter called the Patient) colonized with CRKP in the gut and located in a separate, small ward within the ICU. The study also retrospectively investigated CRKP-HAIs in the same ICU. The relationship and transmission between CRKP isolates from the Patient and HAI events in the ICU were explored with comparative genomics.

RESULTS

In this study, 65 CRKP-HAI cases occurred during the investigation period. Seven CRKP-HAI outbreaks were also observed. A total of 95 nonrepetitive CRKP isolates were collected, including 32 strains from the Patient in the separate small ward. Phylogenetic analysis based on core genome single-nucleotide polymorphism (cgSNP) showed that there were five possible CRKP clonal transmission events and two clonal outbreaks (A1, A2) during the study. CRKP strains from the Patient did not cause CRKP between-patient transmission or outbreaks in the ICU during the 5-year study period.

CONCLUSION

The presence of a long-term hospitalized patient carrying CRKP and positioned in a separate, small ward did not lead to CRKP transmission or infection outbreaks in the ICU. Combining a small-ward ICU layout with normative HAI control measures for multidrug-resistant pathogen infection was effective in reducing CRKP transmission.

A new species of Orthobula Simon, 1897 (Araneae, Trachelidae) from South China

Background

Only one trachelid species, Trachelassinensis Chen, Peng & Zhao, 1995 has been recorded from Jiangxi Province to date.

New information

A new species, Orthobulajiangxi Liu, sp. n., is described from Jiangxi Province of China, based on both sexes. Morphological illustrations are provided and its distribution is mapped.

Antimicrobial Resistance Policy Protagonists and Processes—A Qualitative Study of Policy Advocacy and Implementation

Antimicrobial resistance (AMR) fundamentally weakens societal foundations economically and in health care. The development of well-considered policies against AMR is important. However, in many places, AMR policy implementation remains elusive. This study aims to identify enablers and deterrents as well as processes and conditions in AMR policy advocacy. It also aims to identify AMR implementation conditions where AMR national policies are adopted and, to a certain extent, formulated and implemented. This study adopts qualitative research methodology and applies the Grounded Theory Framework to identify thematic findings from interviews conducted in China, Japan, Norway, the United Kingdom (UK), and the United States of America (US). It was identified that AMR policy protagonists are critical to filtering AMR issues and identifying policies “fit to prioritize” and “fit to implement”. They have helped move policy prioritization needles in the UK and the US and engaged in diplomatic efforts in the UK. In these cases, no clientelism was considered. In the US, protagonists who talked to the right decision-makers in the right office at the right time both moved AMR issues from individuals to institutional agenda and from social norms to policy agenda. To conclude, there are three thematic policy conditions that are significant to AMR policy advocacy and implementation: committed personal championship, institutionalization of policies, and social norms facilitate AMR policy advocacy and implementation.

Population genomics of emerging Elizabethkingia anophelis pathogens reveals potential outbreak and rapid global dissemination

Elizabethkingia anophelis is an emerging species and have increasingly been reported to cause life-threatening infections and even outbreaks in humans. Nevertheless, there is little data regarding the E. anophelis geographical distribution, phylogenetic structure, and transmission across the globe, especially in Asia. We utilize whole genome sequencing (WGS) data to define a global population framework, phylogenetic structure, geographical distribution, and transmission evaluation of E. anophelis pathogens. The geographical distribution diagram revealed the emerging pathogenic bacteria already distributed in various countries worldwide, especially in the USA and China. Strikingly, phylogenetic analysis showed a part of our China original E. anophelis shared the same ancestor with the USA outbreak strain, which implies the possibility of localized outbreaks and global spread. These closer related strains also contained ICEEaI, which might insert into a disrupted DNA repair mutY gene and made the strain more liable to mutation and outbreak infection. BEAST analysis showed that the most recent common ancestor for ICEEaI E. anophelis was dated twelve years ago, and China might be the most likely recent source of this bacteria. Our study sheds light on the potential possibility of E. anophelis causing the large-scale outbreak and rapid global dissemination. Continued genomic surveillance of the dynamics of E. anophelis populations will generate further knowledge for optimizing future prevent global outbreak infections.

Efficacy and safety of novel carbapenem–β-lactamase inhibitor combinations: Results from phase II and III trials

Objectives

The addition of novel β-lactamase inhibitors to carbapenems restores the activity against multidrug-resistant Gram-negative bacteria. The aim of this study was to summarize the evidence on the efficacy and safety of novel carbapenem–β-lactamase inhibitor combinations.

Methods

We conducted a meta-analysis of clinical trials comparing novel carbapenem–β-lactamase inhibitor combinations with comparators to assess the clinical and microbiological responses, mortality, and adverse events (AEs).

Results

A total of 1,984 patients were included. The pooled risk ratios (RRs) of clinical cure, microbiological eradication, all-cause mortality, and 28-day mortality were 1.11 (95% CI: 0.98–1.26), 0.98 (95% CI: 0.82–1.16), 0.90 (95% CI: 0.49–0.94), and 0.68 (95% CI: 0.49–0.94) between the novel carbapenem–β-lactamase inhibitor combinations and control groups. Sensitivity analysis revealed that the phase II trial of imipenem–cilastatin/relebactam (ICR) against complicated urinary tract infections could be the most important factor of heterogeneity for the microbiological response. The therapeutic effect of novel carbapenem–β-lactamase inhibitor combinations was better in meropenem–vaborbactam (MEV), phase III trials, and number of patients less than 200. The RRs of AEs from any cause and serious adverse events (SAEs) for patients receiving novel carbapenem–β-lactamase inhibitor combinations were 0.98 (95% CI: 0.93–1.04) and 1.01 (95% CI: 0.75–1.36), respectively.

Conclusions

ICR and MEV were superior to comparators for clinical cure and survival rate in the treatment of complicated infections, and both were as tolerable as the comparators.

Biofilm formation and antibiotic sensitivity in Elizabethkingia anophelis

Elizabethkingia anophelis has recently gained global attention and is emerging as a cause of life-threatening nosocomial infections. The present study aimed to investigate the association between antimicrobial resistance and the ability to form biofilm among E. anophelis isolated from hospitalized patients in China. Over 10 years, a total of 197 non-duplicate E. anophelis strains were collected. Antibiotic susceptibility was determined by the standard agar dilution method as a reference assay according to the Clinical and Laboratory Standards Institute. The biofilm formation ability was assessed using a culture microtiter plate method, which was determined using a crystal violet assay. Culture plate results were cross-checked by scanning electron microscopy imaging analysis. Among the 197 isolates, all were multidrug-resistant, and 20 were extensively drug-resistant. Clinical E. anophelis showed high resistance to current antibiotics, and 99% of the isolates were resistant to at least seven antibiotics. The resistance rate for aztreonam, ceftazidime, imipenem, meropenem, trimethoprim-sulfamethoxazole, cefepime, and tetracycline was high as 100%, 99%, 99%, 99%, 99%, 95%, and 90%, respectively. However, the isolates exhibited the highest susceptibility to minocycline (100%), doxycycline (96%), and rifampin (94%). The biofilm formation results revealed that all strains could form biofilm. Among them, the proportions of strong, medium, and weak biofilm-forming strains were 41%, 42%, and 17%, respectively. Furthermore, the strains forming strong or moderate biofilm presented a statistically significant higher resistance than the weak formers (p &lt; 0.05), especially for piperacillin, piperacillin-tazobactam, cefepime, amikacin, and ciprofloxacin. Although E. anophelis was notoriously resistant to large antibiotics, minocycline, doxycycline, and rifampin showed potent activity against this pathogen. The data in the present report revealed a positive association between biofilm formation and antibiotic resistance, which will provide a foundation for improved therapeutic strategies against E. anophelis infections in the future.