IS6 family insertion sequences promote optrA dissemination between plasmids varying in transfer abilities

Plasmids are the primary vectors for intercellular transfer of the oxazolidinone and phenicol cross-resistance gene optrA, while insertion sequences (ISs) are mobile genetic elements that can mobilize plasmid-borne optrA intracellularly. However, little is known about how the IS-mediated intracellular mobility facilitates the dissemination of the optrA gene between plasmid categories that vary in transfer abilities, including non-mobilizable, mobilizable, and conjugative plasmids. Here, we performed a holistic genomic study of 52 optrA-carrying plasmids obtained from searches guided by the Comprehensive Antibiotic Resistance Database. Among the 132 ISs identified within 10 kbp from the optrA gene in the plasmids, IS6 family genes were the most prevalent (86/132). Homologous gene arrays containing IS6 family genes were shared between different plasmids, especially between mobilizable and conjugative plasmids. All these indicated the central role of IS6 family genes in disseminating plasmid-borne optrA. Thirty-three of the 52 plasmids were harbored by Enterococcus faecalis found mainly in humans and animals. By Nanopore sequencing and inverse PCR, the potential of the enterococcal optrA to be transmitted from a mobilizable plasmid to a conjugative plasmid mediated by IS6 family genes was further confirmed in Enterococcus faecalis strains recovered from the effluents of anaerobic digestion systems for treating chicken manure. Our findings highlight the increased intercellular transfer abilities and dissemination risk of plasmid-borne optrA gene caused by IS-mediated intracellular mobility, and underscore the importance of routinely monitoring the dynamic genetic contexts of clinically important antibiotic resistance genes to effectively control this critical public health threat. KEY POINTS: • IS6 was prevalent in optrA-plasmids varying in intercellular transfer abilities. • Enterococcal optrA-plasmids were widespread among human, animal, and the environment. • IS6 elevated the dissemination risk of enterococcal optrA-plasmids.

Spatial-temporal trends in leprosy burden and its associations with socioeconomic and physical geographic factors: results from the Global Burden of Disease Study 2019

OBJECTIVES

The purpose of our study was to assess the multiscalar changes in leprosy burden and its associated risk factors over the last three decades.

STUDY DESIGN

We conducted an in-depth examination of leprosy's spatial-temporal trends at multiple geographical scale (global, regional, and national), utilizing information from Global Burden of Disease, Injuries, and Risk Factors Study (GBD 2019).

METHODS

Incidence and the estimated annual percentage change (EAPC) in age-standardized incidence rate (ASIR) of leprosy were determined, with countries categorized based on leprosy incidence changes. We examined socioeconomic and physical geography influences on leprosy incidence via Spearman correlation analysis, using ternary phase diagrams to reveal the synergetic effects on leprosy occurrence.

RESULTS

Globally, incident cases of leprosy decreased by 27.86% from 1990 to 2019, with a reduction in ASIR (EAPC = -2.53), yet trends were not homogeneous across regions. ASIR and EAPC correlated positively with sociodemographic index (SDI), and an ASIR growth appeared in high SDI region (EAPC = 3.07). Leprosy burden was chiefly distributed in Tropical Latin America, Oceania, Central Sub-Saharan Africa, and South Asia. Negative correlations were detected between the incidence of leprosy and factors of SDI, GDP per capita, urban population to total population, and precipitation, whereas the number of refugee population, temperature, and elevation showed opposite positive results.

CONCLUSIONS

Despite a global decline in leprosy over the past three decades, the disparities of disease occurrence at regional and national scales still persisted. Socioeconomic and physical geographic factors posed an obvious influence on the transmission risk of leprosy. The persistence and regional fluctuations of leprosy incidence necessitate the ongoing dynamic and multilayered control strategies worldwide in combating this ancient disease.

Global phylogeography and genomic characterization of blaKPC and blaNDM-positive clinical Klebsiella aerogenes isolates from China, 2016-2022

Carbapenem-resistant Klebsiella aerogenes (CRKA), being one of the members of carbapenem-resistant Enterobacteriaceae (CRE), has caused great public health concern, but with fewer studies compared to other CRE members. Furthermore, studies on phylogenetic analysis based on whole genome Single-Nucleotide Polymorphism (SNP) of CRKA were limited. Here, 20 CRKA isolates (11 blaKPC-2-bearing and 9 blaNDM-1/5-harboring) were characterized by antimicrobial susceptibility testing, conjugation assay, whole genome sequencing (WGS) and bioinformatics analysis. Additionally, the phylogeographic relationships of K. aerogenes were further investigated from public databases. All isolates were multidrug-resistant (MDR) bacteria, and they demonstrated susceptibility to colistin. Most blaKPC-2 or blaNDM-1/5-carrying plasmids were found to be conjugative. Phylogenetic analysis revealed the clonal dissemination of K. aerogenes primarily occurred within clinical settings. Notably, some strains in this study showed the potential for clonal transmission, sharing few SNPs between K. aerogenes and KPC- and/or NDM-positive K. aerogenes isolated from various countries. The STs of K. aerogenes strains had significant diversity. WGS analysis showed that the IncFIIK plasmid was the most prevalent carrier of blaKPC-2, and, blaNDM-1/5 were detected on the IncX3 plasmids. The Tn6296 and Tn3000 transposons were most common vehicles for facilitating the transmission of blaKPC-2 and blaNDM-1/5, respectively. This study highlights the importance of continuous screening and surveillance by WGS for analysis of drug-resistant strains in hospital settings, and provide clinical information that supports epidemiological and public health research on human pathogens.

Detection and genomic characterization of Klebsiella pneumoniae and Escherichia coli harboring tet(X4) in black kites (Milvus migrans) in Pakistan

The emergence of plasmid-mediated tigecycline resistance gene tet(X4) among clinically relevant bacteria has promoted significant concerns, as tigecycline is considered a last-resort drug against serious infections caused by multidrug-resistant bacteria. We herein focused on the isolation and molecular characterization of tet(X4)-positive Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) in wild bird populations with anthropogenic interaction in Faisalabad, Pakistan. A total of 150 birds including black kites (Milvus migrans) and house crows (Corvus splendens) were screened for the presence of tigecycline resistance K. pneumoniae and E. coli. We found two K. pneumoniae and one E. coli isolate carrying tet(X4) originating from black kites. A combination of short- and long-read sequencing strategies showed that tet(X4) was located on a broad host range IncFII plasmid family in K. pneumoniae isolates whereas on an IncFII-IncFIB hybrid plasmid in E. coli. We also found an integrative and conjugative element ICEKp2 in K. pneumoniae isolate KP8336. We demonstrate the first description of tet(X4) gene in the WHO critical-priority pathogen K. pneumoniae among wild birds. The convergence of tet(X4) and virulence associated ICEKp2 in a wild bird with known anthropogenic contact should be further investigated to evaluate the potential epidemiological implications. The potential risk of global transmission of tet(X4)-positive K. pneumoniae and E. coli warrant comprehensive evaluation and emphasizes the need for effective mitigation strategies to reduce anthropogenic-driven dissemination of AMR in the environment.

[A preliminary in vitro and in vivo study of endothelial cell pyroptosis in the periodontal inflammatory environment]

Objective: To observe whether endothelial cells undergo pyroptosis in the inflammatory periodontal environment by using a model in vivo and in vitro, providing an experimental basis for indepth understanding of the underlying pathogenesis of periodontitis. Methods: According to the classification of periodontal diseases of 2018, gingival tissues were collected from periodontally healthy subjects and patients with stage Ⅲ-Ⅳ, grade C periodontitis, who presented Department of Oral and Maxillofacial Surgery and Department of Periodontology, School of Stomatology, The Fourth Military Medical University from April to May 2022. Immunohistochemical staining was performed to detect the expression level and distribution of gasdermin D (GSDMD), a hallmark protein of cell pyroptosis, in gingival tissues. Periodontitis models were established in each group by ligating the maxillary second molar teeth of three mice for 2 weeks (ligation group). The alveolar bone resorption was determined by micro-CT (mice without ligation treatment were used as the control group), and the colocalization of GSDMD and CD31 were quantitatively analyzed by immunofluorescence staining in gingival tissues of healthy and inflammatory mice. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg) combined with adenosine triphosphate (ATP) at various concentrations of 0.5, 1.0, 2.5, 5.0, and 10.0 mg/L, respectively, and the 0 mg/L group was set as the control group at the same time. Scanning electron microscopy was used to observe the morphology of HUVECs. Western blotting was used to detect the expression of gasdermin D-N terminal domains (GSDMD-N) protein and immunofluorescence cell staining was used to detect the expression and distribution of GSDMD. Cell counting kit-8 (CCK-8) was used to detect the proliferative ability of HUVECs, and propidium iodide (PI) staining was used to detect the integrity of cell membrane of HUVECs. Results: Immunohistochemistry showed that GSDMD in gingival tissues of periodontitis was mainly distributed around blood vessels and its expression level was higher than that in healthy tissues. Micro-CT showed that alveolar bone resorption around the maxillary second molar significantly increased in ligation group mice compared with control subjects (t=8.88, P<0.001). Immunofluorescence staining showed significant colocalization of GSDMD with CD31 in the gingival vascular endothelial cells in mice of ligation group. The results of scanning electron microscopy showed that there were pores of different sizes, the typical morphology of pyroptosis, on HUVECs cell membranes in the inflammatory environment simulated by ATP combined with different concentrations of LPS, and 2.5 mg/L group showed the most dilated and fused pores on cell membranes, with the cells tended to lyse and die. Western blotting showed that the expression of GSDMD-N, the hallmark protein of cell pyroptosis, was significantly higher in 2.5 and 5.0 mg/L groups than that in the control group (F=3.86, P<0.01). Immunofluorescence cell staining showed that the average fluorescence intensity of GSDMD in 2.5 mg/L group elevated the most significantly in comparison with that in the control group (F=35.25, P<0.001). The CCK-8 proliferation assay showed that compared to the control group (1.00±0.02), 0.5 mg/L (0.52±0.07), 1.0 mg/L (0.57±0.10), 2.5 mg/L (0.58±0.04), 5.0 mg/L (0.55±0.04), 10.0 mg/L (0.61±0.03) groups inhibited cell proliferation (F=39.95, P<0.001). PI staining showed that the proportion of positive stained cells was highest [(56.07±3.22)%] in 2.5 mg/L group (F=88.24, P<0.001). Conclusions: Endothelial cells undergo significant pyroptosis in both and periodontal inflammatory environments, suggesting that endothelial cell pyroptosis may be an important pathogenic factor contributing to the pathogenesis of periodontitis.

National genomic epidemiology investigation revealed the spread of carbapenem-resistant Escherichia coli in healthy populations and the impact on public health

BACKGROUND

Carbapenem-resistant Escherichia coli (CREC) has been considered as WHO priority pathogens, causing a great public health concern globally. While CREC from patients has been thoroughly investigated, the prevalence and underlying risks of CREC in healthy populations have been overlooked. Systematic research on the prevalence of CREC in healthy individuals was conducted here. We aimed to characterize CREC collected from healthy populations in China between 2020 and 2022 and to compare the genomes of CREC isolates isolated from healthy individuals and clinical patients.

METHODS

We present a nationwide investigation of CREC isolates among healthy populations in China, employing robust molecular and genomic analyses. Antimicrobial susceptibility testing, whole-genome sequencing, and bioinformatics were utilized to analyze a cohort of CREC isolates (n = 113) obtained from fecal samples of 5 064 healthy individuals. Representative plasmids were extracted for third-generation nanopore sequencing. We previously collected 113 non-duplicate CREC isolates (59 in 2018, 54 in 2020) collected from ICU patients in 15 provinces and municipalities in China, and these clinical isolates were used to compare with the isolates in this study. Furthermore, we employ comparative genomics approaches to elucidate molecular variations and potential correlations between clinical and non-clinical CREC isolates.

RESULTS

A total of 147 CREC isolates were identified from 5 064 samples collected across 11 provinces in China. These isolates were classified into 64 known sequence types (STs), but no dominant STs were observed. In total, seven carbapenemase genes were detected with blaNDM-5 (n = 116) being the most prevalent one. Genetic environments and plasmid backbones of blaNDM were conserved in CREC isolated from healthy individuals. Furthermore, we compared clinical and healthy human-originated CRECs, revealing noteworthy distinctions in 23 resistance genes, including blaNDM-1, blaNDM-5, and blaKPC (χ2 test, p < 0.05). Clinical isolates contained more virulence factors associated with iron uptake, adhesion, and invasion than those obtained from healthy individuals. Notably, CREC isolates generally found healthy people are detected in hospitalized patients.

CONCLUSIONS

Our findings underscore the significance of healthy populations-derived CRECs as a crucial reservoir of antibiotic resistance genes (ARGs). This highlights the need for ongoing monitoring of CREC isolates in healthy populations to accurately assess the potential risks posed by clinical CREC isolates.

Analysis of the transmission chain of carbapenem-resistant Enterobacter cloacae complex infections in clinical, intestinal and healthcare settings in Zhejiang province, China (2022-2023)

Considerable attention is given to intensive care unit-acquired infections; however, research on the transmission dynamics of multichain carbapenemase-resistant Enterobacter cloacae complex (CRECC) outbreaks remains elusive. A total of 118 non-duplicated CRECC strains were isolated from the clinical, intestinal, and hospital sewage samples collected from Zhejiang province of China during 2022-2023. A total of 64 CRECC strains were isolated from the hospital sewage samples, and their prevalence increased from 10.0 % (95 % confidence interval, CI = 0.52-45.8 %) in 2022 to 63.6 % (95 % CI = 31.6-87.6 %) in 2023. Species-specific identification revealed that Enterobacter hormaechei was the predominant CRECC species isolated in this study (53.4 %, 95 % CI = 44.0-62.6 %). The antimicrobial susceptibility profiles indicated that all 118 CRECC strains conferred high-level resistance to β-lactam antibiotics, ceftacillin/avibactam, and polymyxin. Furthermore, all CRECC strains exhibited resistance to β-lactams, quinolones, and fosfomycin, with a higher colistin resistance rate observed in the hospital sewage samples (67.2 %, 95 % CI = 54.2-78.1 %). Several antibiotic resistance genes were identified in CRECC strains, including Class A carbapenemases (blaKPC-2) and Class B carbapenemases (blaNDM-1/blaIMP), but not Class D carbapenemases. The WGS analysis showed that the majority of the CRECC strains carried carbapenemase-encoding genes, with blaNDM-1 being the most prevalent (86.9 %, 95 % CI = 77.4-92.9 %). Furthermore, sequence typing revealed that the isolated CRECC strains belonged to diverse sequence types (STs), among which ST418 was the most prevalent blaNDM-positive strain. The high risk of carbapenemase-producing ST418 E. hormaechei and the blaNDM-harboring IncFIB-type plasmid (81.4 %, 95 % CI = 72.9-87.7 %) were detected and emphasized in this study. This study provides valuable insights into the prevalence, antimicrobial resistance, genomic characteristics, and plasmid analysis of CRECC strains in diverse populations and environments. The clonal relatedness analysis showed sporadic clonal transmission of ST418 E. hormaechei strains, supporting inter-hospital transmission.

Gramine sensitizes Klebsiella pneumoniae to tigecycline killing

BACKGROUND

The presence of plasmid-mediated resistance-nodulation-division (RND) efflux pump gene cluster tmexCD1-toprJ1 and its related variants has been associated with heightened resistance to tigecycline, thus diminishing its effectiveness. In this study, we explored the potential of gramine, a naturally occurring indole alkaloid, as an innovative adjuvant to enhance the treatment of infections caused by K. pneumoniae carrying tmexCD-toprJ-like gene clusters.

METHODS

The synergistic potential of gramine in combination with antibiotics against both planktonic and drug-tolerant multidrug-resistant Enterobacterales was evaluated using the checkerboard microbroth dilution technique and time-killing curve analyses. Afterwards, the proton motive force (PMF) of cell membrane, the function of efflux pump and the activity of antioxidant system were determined by fluorescence assay and RT-PCR. The intracellular accumulation of tigecycline was evaluated by HPLC-MS/MS. The respiration rate, bacterial ATP level and the NAD+/NADH ratio were investigated to reveal the metabolism state. Finally, the safety of gramine was assessed through hemolytic activity and cytotoxicity assays. Two animal infection models were used to evaluate the in vivo synergistic effect.

RESULTS

Gramine significantly potentiated tigecycline and ciprofloxacin activity against tmexCD1-toprJ1 and its variants-positive pathogens. Importantly, the synergistic activity was also observed against bacteria in special physiological states such as biofilms and persister cells. The mechanism study showed that gramine possesses the capability to augment tigecycline accumulation within cells by disrupting the proton motive force (PMF) and inhibiting the efflux pump functionality. In addition, the bacterial respiration rate, intracellular ATP level and tricarboxylic acid cycle (TCA) were promoted under the treatment of gramine. Notably, gramine effectively restored tigecycline activity in multiple animal infection models infected by tmexCD1-toprJ1 positive K. pneumoniae (RGF105-1).

CONCLUSION

This study provides the first evidence of gramine's therapeutic potential as a novel tigecycline adjuvant for treating infections caused by K. pneumoniae carrying tmexCD-toprJ-like gene clusters.

Construct validation of machine learning for accurately predicting the risk of postoperative surgical site infection following spine surgery

BACKGROUND

This study aimed to evaluate the risk factors for machine learning (ML) algorithms in predicting postoperative surgical site infection (SSI) following spine surgery.

METHODS

This prospective cohort study included 986 patients who underwent spine surgery at Taizhou People's Hospital Affiliated to Nanjing Medical University from January 2015 to October 2022. Supervised ML algorithms included support vector machine, logistic regression, random forest, XGboost, decision tree, k-nearest neighbour, and naïve Bayes (NB), which were tested and trained to develop a predicting model. The ML model performance was evaluated from the test dataset. We gradually analysed their accuracy, sensitivity, and specificity, as well as the positive predictive value, negative predictive value, and area under the curve.

RESULTS

The rate of SSI was 9.33%. Using a backward stepwise approach, we identified that the remarkable risk factors predicting SSI in the multi-variate Cox regression analysis were age, body mass index, smoking, cerebrospinal fluid leakage, drain duration and pre-operative albumin level. Compared with other ML algorithms, the NB model had the highest performance in seven ML models, with an average area under the curve of 0.95, sensitivity of 0.78, specificity of 0.88, and accuracy of 0.87.

CONCLUSIONS

The NB model in the ML algorithm had excellent calibration and accurately predicted the risk of SSI compared with the existing models, and might serve as an important tool for the early detection and treatment of SSI following spinal infection.

Adaptive evolution of plasmid and chromosome contributes to the fitness of a blaNDM-bearing cointegrate plasmid in Escherichia coli

Large cointegrate plasmids recruit genetic features of their parental plasmids and serve as important vectors in the spread of antibiotic resistance. They are now frequently found in clinical settings, raising the issue of how to limit their further transmission. Here, we conducted evolutionary research of a large blaNDM positive cointegrate within Escherichia coli C600, and discovered that adaptive evolution of chromosome and plasmid jointly improved bacterial fitness, which was manifested as enhanced survival ability for in vivo and in vitro pairwise competition, biofilm formation, and gut colonization ability. From the plasmid aspect, large-scale DNA fragment loss is observed in an evolved clone. Although the evolved plasmid imposes a negligible fitness cost on host bacteria, its conjugation frequency is greatly reduced, and the deficiency of anti-SOS gene psiB is found responsible for the impaired horizontal transferability rather than the reduced fitness cost. These findings unveil an evolutionary strategy in which the plasmid horizontal transferability and fitness cost are balanced. From the chromosome perspective, all evolved clones exhibit parallel mutations in the transcriptional regulatory stringent starvation protein A gene sspA. Through a sspA knockout mutant, transcriptome analysis, in vitro transcriptional activity assay, RT-qPCR, motility test, and scanning electron microscopy techniques, we demonstrated that the mutation in sspA reduces its transcriptional inhibitory capacity, thereby improving bacterial fitness, biofilm formation ability, and gut colonization ability by promoting bacterial flagella synthesis. These findings expand our knowledge of how cointegrate plasmids adapt to new bacterial hosts.

Emergence of an ST1934:KL121 hypervirulent Klebsiella pneumoniae carrying a novel virulence-resistance hybrid plasmid with chromosomal integration of ICEKp1

To identify the phenotypic and genomic characteristics of K. pneumoniae KP43 from bloodstream infection. KP43 was resistant to ticarcillin and tetracycline and was hypervirulent in the Galleria mellonella larvae infection model, positive for string test, and possessed high-level macrophage killing resistance. The hypervirulence phenotype was associated with the chromosome integration of ICEKp1 carrying iroBCDN-iroP, rmpADC, and peg-344, and a novel plasmid pKP43_vir_amr harboring iutAiucABCD. pKP43_vir_amr was an IncFIBκ/FII virulence-resistance hybrid conjugative plasmid which also carried antibiotic resistance genes. The emergence of such a strain and the spread of the novel virulence-resistance plasmid might pose a potential threat to public health.

Molecular epidemiology, phenotypic and genomic characterization of antibiotic-resistant enterococcal isolates from diverse farm animals in Xinjiang, China

Multidrug-resistant (MDR) bacteria in farm environments can be transferred to humans through the food chain and occupational exposure. Enterococcus infections caused by linezolid resistant enterococci (LRE) are becoming more challenging to treat as their resistance to antibiotics intensifies. Therefore, this study investigated the molecular epidemiology, phenotypic and genomic characterization of enterococci in seven species of farm animals (sheep, chicken, swine, camel, cattle, equine, pigeon) anal swab from Xinjiang, China by agar dilution method, polymerase chain reaction (PCR), whole-genome sequencing (WGS) and bioinformatics analysis. A total of 771 samples were collected, 599 (78 %) were contaminated with Enterococcus spp., among which Enterococcus faecalis (350/599) was dominant. Antimicrobial susceptibility testing showed that high resistance was observed in rifampicin (80 %), tetracycline (71 %), doxycycline (71 %), and erythromycin (69 %). The results of PCR showed the highest prevalent antibiotic resistance genes (ARGs) were aac(6')-aph(2″) (85 %), followed by tet(M) (73 %), erm(B) (62 %), and aph(3')-IIIa (61 %). Besides, 29 optrA-carrying E. faecalis isolates belonging to 13 STs (including 3 new alleles) were detected, with ST714 (31 %, 9/29) being the dominant ST type. The phylogenetic tree showed that optrA-carrying E. faecalis prevalent in the intensive swine farm is mainly caused by clonal transmission. Notably, optrA gene in Enterococcus spp. isolate from camel was first characterized here. WGS of E. faecalis F109 isolate from camel confirmed the colocalization of optrA with other five ARGs in the same plasmid (pAFL-109F). The optrA-harboring genetic context is IS1216E-fexA-optrA-erm(A)-IS1216E. This study highlights the prevalence of MDR Enterococcus (≥88 %) and four ARGs (≥75 %) in swine (intensive farming), cattle (commercial farming), and chickens (backyard farming) are high and also highlights that optrA-carrying E. faecalis of farm animals incur a transmission risk to humans through environment, food consumption and others. Therefore, antibiotic-resistant bacteria (ARB) monitoring and effective control measures should be strengthened and implemented in diverse animals.

[Effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022]

OBJECTIVE

To evaluate the effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022, so as to provide insights into formulation of future control interventions.

METHODS

Data pertaining to comprehensive echinococcosis control measures with emphasis on management of infectious source and echinococcosis surveillance in Sichuan Province from 2010 to 2022 were collected. The effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source was evaluated with prevalence of human echinococcosis, detection of newly diagnosed echinococcosis patients, prevalence of Echinococcus infection in domestic dogs, prevalence of cystic echinococcosis in livestock, prevalence of alveolar echinococcosis in small mammals and awareness of echinococcosis control knowledge, and Spearman's rank correlation analysis.

RESULTS

The prevalence of human echinococcosis reduced from 1.08% in 2010 to 0.40% in 2022 in Sichuan Province (χ2 = 1 482.97, P < 0.05), with a reduction from 0.30% to 0.02% in the detection of newly diagnosed echinococcosis cases (χ2 = 2 776.41, P < 0.05), a reduction from 15.87% to 0.46% in the prevalence of Echinococcus infection in domestic dogs (χ2 = 20 823.96, P < 0.05), a reduction from 8.05% to 1.07% in the prevalence of cystic echinococcosis in livestock (χ2 = 1 296.02, P < 0.05), and the awareness of echinococcosis control knowledge increased from 50.65% to 95.24% (χ2 = 34 938.63, P < 0.05); in addition, there was a year-specific prevalence rate of alveolar echinococcosis in small mammals (χ2 = 164.07, P < 0.05). Spearman's rank correlation analysis revealed that the detection of newly diagnosed echinococcosis cases correlated positively with the prevalence of Echinococcus infections in domestic dogs (rs = 0.823, P < 0.05) and the prevalence of cystic echinococcosis in livestock (rs = 0.795, P < 0.05), and correlated negatively with the awareness of echinococcosis control knowledge (rs = - 0.918, P < 0.05), and the prevalence of Echinococcus infection in domestic dogs correlated positively with the prevalence of cystic echinococcosis in livestock (rs = 0.753, P < 0.05) and negatively with the awareness of echinococcosis control knowledge (rs = -0.747, P < 0.05); however, there was no correlation between the prevalence of Echinococcus infections in domestic dogs and the prevalence of alveolar echinococcosis in small mammals (rs = -0.750, P > 0.05).

CONCLUSIONS

The comprehensive echinococcosis control measures with emphasis on management of infectious source had achieved remarkable effectiveness in Sichuan Province; however, the transmission chain of echinococcosis has not been interrupted. Reinforced comprehensive echinococcosis control measures with emphasis on management of infectious source and sustained tracking evaluation of the effectiveness are recommended in Sichuan Province.

Multi-channel synthetic aperture infrared imaging and experimental research

The synthetic aperture infrared radio imaging method based on laser local oscillator coherent detection has potential application value for astronomical observations. This paper studies the multi-channel synthetic aperture infrared imaging method and conducts experimental verification using a principle prototype. In the short-wave infrared band, five beam-expanding fiber collimators are used to build an observation structure of five laser local oscillator coherent detection channels at a near-field distance of 5 m to carry out physical experiments. The laser local oscillator wavelength is 1.55 µm, and the AD sampling rate is 4 GHz. For the infrared radiation source signal, the phase relationship of the infrared signals between channels acquired by the prototype principle is stable, and the five-channel synthetic aperture imaging results are consistent with the computer simulated results. The experiment verified the effectiveness of the laser local oscillator comprehensive aperture infrared radio imaging method.

Prenatal exposure to PM2.5 components and the risk of different types of preterm birth and the mediating effect of pregnancy complications: a cohort study

OBJECTIVES

This study aims to reveal the single and mixed associations of PM2.5 and its components with very, moderately, and late preterm births and to explore the potential mediating role of pregnancy complications in PM2.5-induced preterm birth.

STUDY DESIGN

This was a retrospective cohort study.

METHODS

We enrolled 168,852 mothers and matched the concentrations of PM2.5 and its five components (OM, SO42-, BC, NO3-, and NH4+) based on their geographical location. Next, we used generalized linear models, quantile g-computation, and mediation analysis to evaluate the associations of PM2.5 and its components with very, moderately, and late preterm births and the mediating role of pregnancy complications.

RESULTS

Prenatal exposure to PM2.5 and its components was associated with preterm birth, and the association was strongest in the third trimester. Preterm birth was associated with co-exposure to a mixture of PM2.5 components in the third trimester, and the contributions of NO3-, NH4+, and BC to the risk of preterm birth were positive. Meanwhile, pregnancy complications mediated PM2.5-induced preterm birth. Moreover, very and moderately preterm births were associated with PM2.5 and its components in the second and third trimesters, and very and late preterm births were associated with co-exposure to a mixture of PM2.5 components in the third trimester.

CONCLUSIONS

Later exposure to PM2.5 during pregnancy will cause earlier preterm birth. Targeted and positive interventions for anthropogenic sources of specific PM2.5 components and pregnancy complications are helpful for preterm birth prevention.

Gga-let-7a-3p inhibits the proliferation and differentiation of chicken intramuscular preadipocytes

1. Intramuscular fat (IMF) is a key parameter for chicken meat quality. IMF deposition is driven by genetic, nutritional and management factors, with genetics being the determining factor. Previous whole transcriptome sequencing revealed that microRNA gga-let-7a-3p was related to lipid metabolism in breast muscle. This study further investigated the potential role of gga-let-7a-3p in IMF deposition.2. The mimic and inhibitor of gga-let-7a-3p were individually transfected into chicken intramuscular preadipocytes. Subsequently, the proliferation and differentiation states of the cells were detected. Transcriptome sequencing was performed on cells transfected with gga-let-7a-3p mimic.3. The results indicated that gga-let-7a-3p suppressed the mRNA levels of proliferation and differentiation-related genes, as well as the protein levels. EdU and Oil Red O assays revealed that gga-let-7a-3p restrained preadipocyte proliferation and differentiation. In addition, a total of 333 up-regulated genes and 807 down-regulated genes were identified in cells transfected with gga-let-7a-3p mimic. Using Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis, differential genes were found to be enriched in processes such as the peroxisome proliferator activated receptor (PPAR) signalling pathway and oxidative phosphorylation.4. The study demonstrated that gga-let-7a-3p inhibits the proliferation and differentiation of chicken intramuscular preadipocytes, which provides new understanding to further unravel the function of gga-let-7a-3p.

Anthropogenic, biogenic, and photochemical influences on surface formaldehyde and its significant decadal (2006-2017) decrease in the Lewiston-Clarkston valley of the northwestern United States

Formaldehyde (HCHO) is a key carcinogen and plays an important role in atmospheric chemistry. Both field measurements and Positive Matrix Factorization (PMF) modeling have been employed to investigate the concentrations and sources of HCHO in the Lewiston-Clarkston (LC) valley of the mountainous northwestern U.S. Different instruments were deployed to measure surface formaldehyde and other related compounds in July of 2016 and 2017. The measurements reveal that the average HCHO concentrations have significantly decreased to 2-5 ppb in the LC valley in comparison to its levels (10-20 ppb) observed in July 2006. This discovery with surface measurements deserves attention given that satellite retrievals showed an increasing long-term trend from 2005 to 2014 in total vertical column density of HCHO in the region, suggesting that satellite instruments may not adequately resolve small valleys in the mountainous region. Our PMF modeling identified four major sources of HCHO in the valley: (1) emissions from a local paper mill, (2) secondary formation and background, (3) biogenic sources, and (4) traffic. This study reveals that the emissions from the paper mill cause high HCHO spikes (6-19 ppb) in the early morning. It is found that biogenic volatile organic compounds (VOCs) in the area are influenced by national forests surrounding the region (e.g., Nez Perce-Clearwater, Umatilla, Wallowa-Whitman, and Idaho Panhandle National Forests). The results provide useful information for developing strategies to control HCHO levels and have implications for future HCHO studies in atmospheric chemistry, which affects secondary aerosols and ozone formation.

[Rudimentary horn pregnancy: clinical analysis of 12 cases and literature review]

Objective: To investigate the clinical characteristics, treatments and fertility recovery of rudimentary horn pregnancy (RHP). Methods: The clinical data of 12 cases with RHP diagnosed and treated in Peking University Third Hospital from January 1, 2010 to December 31, 2022 were retrospectively analyzed. Clinical informations, diagnosis and treatments of RHP and the pregnancy status after surgery were analyzed. Results: The median age of 12 RHP patients was 29 years (range: 24-37 years). Eight cases of pregnancy in residual horn of uterus occurred in type Ⅰ residual horn of uterus, 4 cases occurred in type Ⅱ residual horn of uterus; among which 5 cases were misdiagnosed by ultrasound before surgery. All patients underwent excision of residual horn of uterus and affected salpingectomy. After surgery, 9 patients expected future pregnancy, and 3 cases of natural pregnancy, 2 cases of successful pregnancy through assisted reproductive technology. Four pregnancies resulted in live birth with cesarean section, and 1 case resulted in spontaneous abortion during the first trimester of pregnancy. No uterine rupture or ectopic pregnancy occurred in subsequent pregnancies. Conclusions: Ultrasonography could aid early diagnosis of RHP while misdiagnosis occurred in certain cases. Thus, a comprehensive judgment and decision ought to be made based on medical history, physical examination and assisted examination. Surgical exploration is necessary for diagnosis and treatment of RHP. For infertile patients, assisted reproductive technology should be applied when necessary. Caution to prevent the occurrence of pregnancy complications such as uterine rupture, and application of cesarean section to terminate pregnancy are recommended.

J-2156, a small molecule somatostatin type 4 receptor agonist, alleviated hindpaw hypersensitivity in the streptozotocin-induced rat model of painful diabetic neuropathy but with a 2-fold decrease in potency at an advanced stage in the model, mimicking morphine

There is a large unmet need for novel pain-killers to improve relief of painful diabetic neuropathy (PDN). Herein, we assessed the efficacy of the somatostatin type 4 (SST4) receptor agonist, J-2156, for relief of PDN in rats. Diabetes was induced with streptozotocin (STZ; 70 mg/kg) and bilateral hindpaw hypersensitivity was fully developed by 8-week post-STZ. In the intervals, 8-12-weeks (morphine-sensitive phase; Phase 1) and 16-18-weeks (morphine-hyposensitive phase; Phase 2) post-STZ, rats received a single dose of intraperitoneal (i.p.) J-2156 (10, 20, 30 mg/kg), gabapentin (100 mg/kg i.p.), subcutaneous morphine (1 mg/kg) or vehicle. Hindpaw withdrawal thresholds (PWTs) were assessed using von Frey filaments pre-dose and at regular intervals over 3-h post-dose. In Phase 1, J-2156 at 30 mg/kg evoked significant anti-allodynia in the hindpaws with maximal effect at 1.5 h compared with 1 h for gabapentin and morphine. The durations of action for all three compounds were greater than 3 h. The corresponding mean (±SEM) extent and duration of anti-allodynia (ΔPWT AUC) for gabapentin did not differ significantly from that for J-2156 (30 mg/kg) or morphine. However, in Phase 2, the ΔPWT AUC for morphine was reduced to approximately 25% of that in Phase 1, mirroring our previous work. Similarly, the mean (±SEM) ΔPWT AUC for J-2156 (30 mg/kg) in Phase 2 was approximately 45% of that for Phase 1 whereas for gabapentin the mean (±SEM) ΔPWT AUCs did not differ significantly (p > 0.05) between the two phases. Our findings further describe the preclinical pain relief profile of J-2156 and complement previous work in rat models of inflammatory pain, neuropathic pain and low back pain. SST4 receptor agonists hold promise as novel therapeutics for the relief of PDN, a type of peripheral neuropathic pain that is often intractable to relief with clinically used drug treatment options.

Fetal cardiovascular changes during open and fetoscopic in-utero spina bifida closure

OBJECTIVE

Laparotomy-assisted fetoscopic closure of spina bifida utilizing heated-humidified carbon dioxide gas has been associated with less maternal morbidity than open in-utero spina bifida closure. Fetal cardiovascular changes during these surgical interventions are not well defined. Our objective was to compare fetal bradycardia (defined as fetal heart rate (FHR)<110 bpm over 10 minutes) and changes in umbilical artery Doppler parameters throughout open in-utero closure with those observed during laparotomy-assisted fetoscopic closure.

METHODS

We conducted a prospective cohort study of 22 open and 46 fetoscopic consecutive in-utero closures between 2019 and 2023. Both cohorts had similar preoperative counseling and clinical management. FHR and umbilical artery velocimetry were systematically obtained during preoperative assessment, every 5 minutes during the intraoperative period, and in the postoperative assessment. FHR, pulsatility indexes and end-diastolic flows were segmented into hourly periods during surgery, and the lowest values were averaged for analysis. Umbilical vein maximum velocities were measured in the fetoscopic cohort. Each fetal heart rate recording time point was correlated to maternal parameters, including heart rate, systolic and diastolic blood pressures.

RESULTS

Fetal bradycardia occurred in 4/22 cases (18.2%) of open in-utero closure and in 21/46 cases (45.7%) of fetoscopic closure. FHR gradually decreased in both cohorts after general anesthesia and decreased further during surgery. FHR were significantly lower after two hours of surgery in the fetoscopic closure than in the open in-utero closure group. In addition, the FHR (BPM) change in the final stages of the fetal surgery from the baseline FHR was significantly lower in the fetoscopic cohort (-32.3 (-35.7, -29.1)) compared to the open cohort (-23.5 (-28.1, -18.8)) (p=0.002). Abnormal end-diastolic flow (defined as absent or reversed end-diastolic flow) in the umbilical artery Doppler velocity occurred in 3/22 (13.6%) of the open closure cohort and in 23/46 (50%) of the fetoscopic closure cohort (p=0.004). There were no differences in umbilical artery end-diastolic flow and pulsatility index between closure techniques during the various stages of assessment.

CONCLUSIONS

We observed a decrease in the FHR and abnormalities in umbilical artery Doppler parameters in both open in-utero and fetoscopic closure groups. Fetal bradycardia was more prominent during fetoscopic closure following heated-humidified carbon dioxide insufflation, but the FHR recovered after cessation of the heated-humidified carbon dioxide. Changes in FHR and umbilical artery Doppler parameters during in-utero spina bifida closure were observed to be transient, no cases required emergency delivery and no fetoscopic closure were converted to open closure. These observations should inform algorithms for perioperative management of fetal bradycardia associated with in-utero spina bifida closure. This article is protected by copyright. All rights reserved.

Achieving ultra-low and -uniform residual magnetic fields in a very large magnetically shielded room for fundamental physics experiments

High-precision searches for an electric dipole moment of the neutron (nEDM) require stable and uniform magnetic field environments. We present the recent achievements of degaussing and equilibrating the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute. We present the final degaussing configuration that will be used for n2EDM after numerous studies. The optimized procedure results in a residual magnetic field that has been reduced by a factor of two. The ultra-low field is achieved with the full magnetic-field-coil system, and a large vacuum vessel installed, both in the MSR. In the inner volume of ∼ 1.4 m 3 , the field is now more uniform and below 300 pT. In addition, the procedure is faster and dissipates less heat into the magnetic environment, which in turn, reduces its thermal relaxation time from 12 h down to 1.5 h .

[Comparing the prognostic value of 3 diagnostic criteria of bronchopulmonary dysplasia in preterm infants]

Objective: To compare the prognostic value of 3 diagnostic criteria of bronchopulmonary dysplasia (BPD) in preterm infants with gestational age<32 weeks. Methods: The retrospective cohort study was conducted to collect the clinical data of 285 preterm infants with BPD admitted to the Department of Neonatology, Children's Hospital Affiliated to Zhengzhou University from January 2019 to September 2021, who were followed up regularly after discharge. The primary composite adverse outcome was defined as death or severe respiratory morbidity from 36 weeks of corrected gestational age to 18 months of corrected age, and the secondary composite adverse outcome was defined as death or neurodevelopmental impairment. According to the primary or secondary composite adverse outcomes, the preterm infants were divided into the adverse prognosis group and the non-adverse prognosis group. The 2001 National Institute of Child Health and Human Development (NICHD) criteria, 2018 NICHD criteria, and 2019 Neonatal Research Network (NRN) criteria were used to diagnose and grade BPD in preterm infants. Chi-square test, Logistic regression analysis, receiver operating characteristic (ROC) curve and Delong test were used to analyze the prognostic value of the 3 diagnostic criteria. Results: The 285 preterm infants had a gestational age of 29.4 (28.1, 30.6) weeks and birth weight of 1 230 (1 000, 1 465) g, including 167 males (58.6%). Among 285 premature infants who completed follow-up, the primary composite adverse outcome occurred in 124 preterm infants (43.5%), and the secondary composite adverse outcome occurred in 40 preterm infants (14.0%). Multivariate Logistic regression analysis showed that severe BPD according to the 2001 NICHD criteria, gradeⅡand Ⅲ BPD according to the 2018 NICHD criteria and grade 2 and 3 BPD according to the 2019 NRN criteria were all risk factors for primary composite adverse outcomes (all P<0.05). ROC curve showed that the area under the curve (AUC) of the 2018 NICHD criteria and 2019 NRN criteria were both higher than that of the 2001 NICHD criteria (0.70 and 0.70 vs. 0.61, Z=4.49 and 3.35, both P<0.001), but there was no significant difference between the 2018 NICHD and 2019 NRN criteria (Z=0.38, P=0.702). Multivariate Logistic regression analysis showed that the secondary composite adverse outcomes were all associated with grade Ⅲ BPD according to the 2018 NICHD criteria and grade 3 BPD according to the 2019 NRN criteria (both P<0.05). ROC curve showed that the AUC of the 2018 NICHD criteria and 2019 NRN criteria were both higher than that of the 2001 NICHD criteria (0.71 and 0.71 vs. 0.58, Z=2.93 and 3.67, both P<0.001), but there was no statistically significant difference between the 2018 NICHD and 2019 NRN criteria (Z=0.02, P=0.984). Conclusion: The 2018 NICHD and 2019 NRN criteria demonstrate good and comparable predictive value for the primary and secondary composite adverse outcomes in preterm infants with BPD, surpassing the predictive efficacy of the 2001 NICHD criteria.

Conjugative plasmids facilitate the transmission of tmexCD2-toprJ2 among carbapenem-resistant Klebsiella pneumoniae

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a great threat to global public health. The emergence of tmexCD-toprJ greatly weakened the efficacy of tigecycline in the treatment of CRKP infections. In this study, we did a comprehensive investigation of the prevalence and genomic features of tmexCD-toprJ in clinical CRKP from 2018 to 2020 in Henan province, China. The results demonstrated tmexCD-toprJ was at a low prevalence in CRKP from patients (7/2031, 0.34 %). Among the seven tmexCD-toprJ positive CRKP, KP18-29 that carried tmexCD1-toprJ1, blaNDM-1 and mcr-8.2 was resistant to tigecycline, carbapenem and colistin simultaneously. While, tmexCD2-toprJ2 together with one or two carbapenemase genes were detected in the remaining strains. Four strains (KP18-231, KP18-2110-2, KP19-3023 and KP19-3088) isolated at different times but shared the same sequence type (ST) 2667 exhibited high genomic similarity, indicating the clonal dissemination of CRKP ST2667 co-producing KPC-2 and TMexCD-TOprJ. Notably, conjugative transmission of the IncFrepB(R1701) plasmid co-harboring tmexCD2-toprJ2 and blaKPC-2 among clinical CRKP isolates belonging to different STs (ST2667, ST978 and ST147) revealed further propagation of tmexCD-toprJ among K. pneumoniae. Such IncFrepB(R1701) plasmids pose a substantial threat to public health due to their mobile resistance to both tigecycline and carbapenem. Online data mining showed isolates carried both carbapenemase genes and tmexCD-toprJ were dominantly isolated from humans, and isolates of animal origins usually carried mcr genes and tmexCD-toprJ, suggesting that these critical resistance genes co-existed in diverse niches. Global surveillance of K. pneumoniae co-harboring tmexCD-toprJ and mcr/carbapenemase genes in various settings with a One Health strategy was warranted.

Global distribution and genomic characteristics of carbapenemase-producing Escherichia coli among humans, 2005-2023

Carbapenem-resistant Escherichia coli (CREC) has become a major public health problem worldwide. To date, there is a limited understanding of the global distribution of CREC. In this study, we performed a comprehensive genomic analysis of 7, 731 CRECs of human origin collected from different countries worldwide between 2005 and 2023. Our results showed that these CRECs were distributed in 75 countries, mainly from the United States (17.49%), China (14.88%), and the United Kingdom (14.73%). Eight carbapenemases were identified among the CRECs analyzed, including KPC, IMP, NDM, VIM, OXA, FRI, GES, and IMI. NDM was the most predominant carbapenemase (52.15%), followed by OXA (30.09%) and KPC (14.72%). Notably, all CRECs carried multiple antibiotic resistance genes (ARGs), with 178 isolates carrying mcr-1 and 9 isolates carrying tet(X). The CREC isolates were classified into 465 known sequence types (STs), with ST167 being the most common (11.5%). Correlation analysis demonstrated the significant role of mobile genetic elements in facilitating the transfer of carbapenem resistance genes. Furthermore, some CRECs from different countries showed high genetic similarity, suggesting clonal transmission exists. According to the GWAS results, the genetic difference of blaNDM-positive CRECs from China were mainly enriched in bacterial Type IV secretion system pathways compared with those from the United Kingdom and the United States. Therefore, continuous global surveillance of CRECs is imperative in the future.

[Clinicopathological and molecular features of metaplastic thymoma]

Objective: To investigate the clinicopathological features, and molecular genetic alterations of metaplastic thymoma (MT). Methods: A total of ten MT cases, diagnosed from 2011 to 2021, were selected from the Department of Pathology of Jinling Hospital, Nanjing University Medical School, Nanjing, China for clinicopathological and immunohistochemical (IHC) examination and clinical follow-up. Fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and YAP1 C-terminus (YAP1-CT) IHC were performed to detect YAP1::MAML2 fusions. Results: There were four males and six females, ranging in age from 29 to 60 years (mean 50 years, median 54 years). Microscopically, all tumors showed a typical biphasic morphology consisting of epithelial components and gradually or abruptly transitioning spindle cell components. The two components were present in varying proportions in different cases. Immunophenotypically, the epithelial cells were diffusely positive for CKpan, CK5/6 and p63. The spindle cells were diffusely positive for vimentin and focally positive for EMA. TdT was negative in the background lymphocytes. Ki-67 proliferation index was less than 5%. YAP1 and MAML2 break-apart FISH analyses showed that all ten cases had narrow split signals with a distance of nearly 2 signal diameters and may be considered false-negative. Using YAP1::MAML2 fusion FISH assays, abnormal fusion signals were observed in all the ten cases. NGS demonstrated YAP1::MAML2 fusions in all eight cases with adequate nucleic acids; in two cases the fusions were detected by DNA sequencing and in eight cases by RNA sequencing. All ten cases of MT demonstrated loss of YAP1 C-terminal expression in epithelioid cells. Conclusions: MT is a rare and low-grade thymic tumor characterized by a biphasic pattern and YAP1::MAML2 fusions. Break-apart FISH assays may sometimes show false-negative results due to the proximity of YAP1 and MAML2, while YAP1 C-terminal IHC is a highly sensitive and specific marker for MT. Loss of YAP1 C-terminal expression can also be used to screen YAP1::MAML2 fusions for possible MT cases.

[Periodic dynamic observation and analysis of cellular and humoral immunity indexes of adults infected with Omicron BA.1]

Objective: To analyze the immunological characteristics and antibody changes of patients infected with the Omicron BA.1 and evaluate the possibility of secondary infection. Methods: A total of 104 patients infected with Omicron BA.1 in the Jinnan District of Tianjin from January 8 to February 2, 2022, were included in the study. The control group and case group were matched 1∶1 based on age, sex and vaccination status. Serum was collected from the case group and control group at 3, 6 and 9 months after infection. The serum levels of interleukin4 (IL-4), IL-5 and interferon-gamma (IFN-γ), as well as the positive rates of IgG, IgG1 and IgG2, were detected by ELISA. Results: The highest concentration of IFN-γ in the case group at 6 months after infection was 145.4 pg/ml, followed by a decrease in concentration. The concentrations of IL-4 and IL-5 began to decrease at 6 months after infection (all P<0.001). There was no significant difference in the IgG2 positive rate between the case group and the control group at 6 months after BA.1 infection. However, at 9 months, there was a significant decrease compared to the control group (P=0.003). The ratio of IFN-γ/IL4 at 3 months after infection in the case group was lower than that in the control group (P<0.001). There was no significant difference in the ratio between the case group and the control group at 9 months after infection. Conclusion: The cellular immune function has been impaired at 3 months after infection with BA.1, and the specific cellular immune and humoral immune functions decrease significantly after 6 months, and the risk of secondary infection increases.

HPV-positive clinically advanced squamous cell carcinoma of the urinary bladder (aBSCC): A comprehensive genomic profiling (CGP) study

BACKGROUND

Advanced bladder squamous cell carcinoma (aBSCC) is an uncommon form of urinary bladder malignancy when compared with the much higher urothelial carcinoma incidence. We studied the genomic alteration (GA) landscape in a series of aBSCC based on the association with human papilloma virus (HPV) to determine if differences in GA would be observed between the positive and negative groups.

METHODS

Using a hybrid capture-based FDA-approved CGP assay, a series of 171 aBSCC were sequenced to evaluate all classes of GA. Tumor mutational burden (TMB) was determined on up to 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on up to 114 loci. Programmed cell death ligand -1 (PD-L1) expression was determined by IHC (Dako 22C3) with negative expression when PD-L1 was 0, lower expression of positivity set at 1 to 49%, and higher expression set at ≥50% expression.

RESULTS

Overall, 11 (6.4%) of the aBSCC were found to harbor HPV sequences (10 HPV16 and 1 HPV 11). HPV+ status was identified slightly more often in women (NS) and in younger patients (P = 0.04); 2 female patients with aBSCC had a prior history of SCC including 1 anal SCC and 1 vaginal SCC. HPV+ aBSCC had fewer GA/tumor (P < 0.0001), more inactivating mutations in RB1 (P = 0.032), and fewer inactivating GA in CDKN2A (P < 0.0001), CDKN2B (P = 0.05), TERT promoter (P = 0.0004) and TP53 (P < 0.0001). GA in genes associated with urothelial carcinoma including FGFR2 and FGFR3 were similar in both HPV+ and HPV- aBSCC groups. MTAP loss (homozygous deletion) which has emerged as a biomarker for PRMT5 inhibitor-based clinical trials was not identified in any of the 11 HPV+ aBSCC cases, which was significantly lower than the 28% positive frequency of MTAP loss in the HPV- aBSCC group (P < 0.0001). MTOR and PIK3CA pathway GA were not significantly different in the 2 groups. Putative biomarkers associated with immunotherapy (IO) response, including MSI and TMB status, were also similar in the 2 groups. PD-L1 expression data was available for a subset of both HPV+ and HPV- cases and showed high frequencies of positive staining which was not different in the 2 groups.

CONCLUSIONS

HPV+ aBSCC tends to occur more often in younger patients. As reported in other HPV-associated squamous cell carcinomas, HPV+ aBSCC demonstrates significantly reduced frequencies of inactivating mutations in cell cycle regulatory genes with similar GA in MTOR and PIK3CA pathways. The implication of HPV in the pathogenesis of bladder cancer remains unknown but warrants further exploration and clinical validation.

[Study on the comparison of postoperative liver injury caused by hepatic arterial perfusion chemotherapy combined with targeted immunotherapy with hepatic arterial chemoembolization combined with targeted immunotherapy for intermediate-and advanced-stage liver cancer]

Objective: To compare the postoperative liver function injury condition in patients with intermediate-and advanced-stage hepatocellular carcinoma (HCC) treated with hepatic artery infusion chemotherapy (HAIC) and hepatic artery chemoembolization (TACE) combined with immune checkpoint inhibitors (ICIs) and multi-target tyrosine kinase inhibitors (TKIs). Methods: Patients with intermediate-and advanced-stage HCC who were admitted and treated with HAIC/TACE+ICIs+TKIs therapy at Nanfang Hospital of Southern Medical University from January 2019 to November 2021, with follow-up up to July 2023, were retrospectively enrolled. The results of liver function tests within one week before interventional surgery and on the first day after surgery were recorded. The degree of postoperative liver injury was graded according to the common terminology criteria for adverse events 5.0 (CTCAE 5.0). The treatment efficacy was evaluated according to RECIST 1.1 criteria. Measurement data were compared between groups using a t-test or a non-parametric rank sum test. Enumeration data were compared between the groups using the χ(2) test or Fisher's exact probability method. The survival condition differences were analyzed by the log-rank method. Results: This study included 82 and 77 cases in the HAIC and TACE groups. There were no statistically significant differences between the two groups of patients in terms of gender, age, physical condition score, number of tumors, presence or absence of liver cirrhosis, Child-Pugh grade, albumin-bilirubin (ALBI) grade, and combined ICIs and TKIs . The HAIC group had later tumor staging, a greater tumor burden, poorer liver reserve function, and a larger proportion of patients in stage C (81.7% vs. 63.6%), χ(2)=6.573, P = 0.01). There were 53 cases (64.6% vs. 32.5%) with a maximum tumor diameter of ≥ 10cm, χ(2)=16.441, P < 0.001), and more patients had a retention rate of ≥ 10% for indocyanine green (ICG) at 15 minutes (68.3% vs. 51.9%, P = 0.035). The postoperative incidence rate of increased levels of alanine aminotransferase, aspartate aminotransferase, and total bilirubin was significantly lower in the HAIC group than that in the TACE group (28.0% vs. 63.6%, χ(2)=20.298, P < 0.001, 54.9% vs. 85.7%, χ(2)=17.917, P < 0.001;40.2% vs. 55.8%, χ(2)=3.873, P = 0.049). The number of patients with postoperative ALBI grade 3 was significantly lower in the HAIC group than that in the TACE group (6.1% vs. 16.9%, χ(2)=4.601, P = 0.032). There was no statistically significant difference in the incidence rate of postoperative hypoalbuminemia, activated partial thromboplastin time, or increased international standardized ratio between the two groups of patients. There was no statistically significant difference in median progression-free survival (7.3 months vs. 8.2 months, P = 0.296) or median overall survival (16.5 months vs. 21.9 months, P = 0.678) between the two groups of patients. Conclusion: The incidence rate of postoperative liver injury is higher in patients with intermediate-and advanced-stage HCC treated with TACE combined with ICIs and TKIs than in patients with HAIC combined with ICIs and TKIs.

Characterisation of a Novel Tigecycline Resistance Gene tet(X22) and its Coexistence with blaNDM-1 in a Pseudomonas caeni Isolate

OBJECTIVES

The emergence of pathogens that are resistant to both tigecycline and carbapenem poses a threat to public health globally. Continuous emergence of novel tet(X) variants accelerates the tigecycline resistance crisis. This study aimed to characterise the novel tigecycline resistance gene tet(X22) and its coexistence with carbapenem resistance gene blaNDM-1 in Pseudomonas caeni.

METHODS

This P. caeni isolate co-harbouring tet(X22) and blaNDM-1 was systematically investigated using antimicrobial susceptibility testing, conjugation assays, genome sequencing, bioinformatic analyses, cloning of tet(X22) and functional analysis, and protein structure prediction.

RESULTS

The carbapenem-resistant and tigecycline-resistant P. caeni isolate CE14 was obtained from chicken faeces in 2022. CE14 carried multiple antibiotic resistance genes, including the novel tet(X22) and blaNDM-1. Tet(X22) exhibited 64.72-90.48% amino acid identity with other variants [Tet(X) to Tet(X21)]. Cloning of the gene tet(X22) and protein structure prediction revealed that Tet(X22) confers resistance to tetracyclines, including tigecycline. tet(X22) and blaNDM-1 were located in two multidrug-resistant regions of the chromosome.

CONCLUSIONS

The occurrence of the novel ISCR2-flanked tet(X22) in P. caeni suggests that the tet(X) variant has adapted to new hosts and may widely spread to further expand the host range. The future global spread of such pathogens co-harbouring tet(X) and blaNDM variants needs to be continuously monitored according to the One Health approach.

A comprehensive analysis of LINC00958 as a prognostic biomarker for head and neck squamous cell carcinomaLi et al

This work focused on exploring whether the long intergenic non-protein coding RNA LINC00958 is associated with the prognosis of head and neck squamous cell carcinoma (HNSCC). Associations of the LINC00958 expression level with clinicopathological features of HNSCC were investigated by logistic regression and Wilcoxon signed-rank test. The Kaplan-Meier method was applied to evaluate patient survival. Clinical data and expression profiles were obtained from The Cancer Genome Atlas (TCGA). Associations of patient clinical characteristics with overall survival (OS), progression-free interval (PFI), and disease-specific survival (DSS) were assessed by univariate and multivariate analysis using the Cox proportional hazard model. Immune cell infiltration analysis and gene set enrichment analysis (GSEA) were applied to determine any significant effects of LINC00958. High LINC00958 expression was related to early pT stage (P < 0.01), primary therapy outcome (P < 0.01), HPV status (P < 0.001), lymphovascular invasion (P < 0.001), and perineural invasion (P < 0.01). The receiver operating characteristic curve showed strong prognostic power for LINC00958 (area under curve = 0.886). High LINC00958 expression predicted poor OS (P = 0.007), DSS (P = 0.036), and PFI (P = 0.040). LINC00958 was related to signalling pathways and the infiltration of certain immune cells. miR-27b-5p was significantly associated with LINC00958, and downstream NT5E predicted poor survival in HNSCC cases. LINC00958 may affect the prognosis by regulating NT5E via miR-27b-5p, and could serve as a possible factor to predict the prognosis of HNSCC, especially oral squamous cell carcinoma.

Integrative conjugative elements mediate the high prevalence of tmexCD3-toprJ1b in Proteus spp. of animal source

IMPORTANCE

The emergence and spread of tmexCD-toprJ have greatly weakened the function of tigecycline. Although studies have demonstrated the significance of Proteus as carriers for tmexCD-toprJ, the epidemic mechanism and characteristics of tmexCD-toprJ in Proteus remain unclear. Herein, we deciphered that the umuC gene in VRIII of SXT/R391 ICEs was a hotspot for the integration of tmexCD3-toprJ1b-bearing mobile genetic elements by genomic analysis. The mobilization and dissemination of tmexCD3-toprJ1b in Proteus were mediated by highly prevalent ICEs. Furthermore, the co-occurrence of tmexCD3-toprJ1b-bearing ICEs with other chromosomally encoded multidrug resistance gene islands warned that the chromosomes of Proteus are significant reservoirs of ARGs. Overall, our results provide significant insights for the prevention and control of tmexCD3-toprJ1b in Proteus.

[Establishment of a patient-derived xenograft humanized mouse model for hepatoblastoma in children]

Objective: To establish a patient-derived xenograft (PDX) humanized mouse model for hepatoblastoma in children. In addition, compare the biological consistency between successfully modeled PDX tumors and primary tumors in children while comparing and analyzing the influence of PDX model modeling success as a key factor. Methods: A PDX tumor model was constructed from fresh tumor tissue samples from 39 children with hepatoblastoma. The tumor growth time and volume size were recorded in detail. Simultaneously, 39 children's data were collected for experimental and clinical analysis. The difference in tumorigenesis rate between different parameters was analyzed by χ (2) test (categorical variable). Continuous variables with a normal distribution were compared using the t-test. Results: After cell passage and pathological diagnosis, 21 cases of hepatoblastoma PDX models were successfully constructed, with a success rate of 53.8% (21/39). Tumor samples from each generation of successfully modeled PDX models had pathology results that were consistent with those of the corresponding primary tumors. The analysis of the key factors affecting the tumor formation rate of PDX revealed that the metastasis rate was more successful in primary tumors than in liver in situ tumors (7/8 vs. 14/31, P = 0.049). However, there was no significant difference between tumor formation rates and pathological subtypes. According to the PDX tumor formation group comparison between the primary tumor and the metastatic tumor, there was no statistically significant difference between the two groups in terms of tumor formation time and tumor volume. Hematoxylin-eosin staining in hepatoblastoma's PDX mouse was consistent with the primary tumor. Immunohistochemistry positivity rates of four proteins, namely hepatocyte antigen (Hepatocyte), phosphatidylinositol glycan 3, β-catenin, and alpha-fetoprotein, in primary tumor tissues and PDX mouse models were 100% vs. 100%, 100% vs. 95.24%, 100% vs. 100%, and 95.24% vs. 85.71%, respectively. Conclusion: A PDX mouse model for hepatoblastoma has been successfully established in children. The tumor formation rate is high, with metastatic tumors having a higher tumor formation rate than primary tumors and transplanted tumors retaining the biological characteristics of primary tumors.

A contemporary analysis of the pre- and intraoperative recognition of multigland parathyroid disease

BACKGROUND

Despite advances in biochemical and radiological identification of parathyroid gland enlargement, primary hyperparathyroidism (PHPT) due to sporadic multigland parathyroid disease (MGPD) remains a perioperative diagnostic dilemma. Failure to recognise MGPD pre- or intraoperatively may negatively impact surgical cure rates and result in persistent PHPT and ongoing patient morbidity.

METHODS

We have conducted a comprehensive review of published literature in attempt to determine factors that could aid in reliably diagnosing sporadic MGPD pre- or intraoperatively. We discuss preoperative clinical features and examine pre- and intraoperative biochemical and imaging findings concentrating on those areas that give practicing surgeons and the wider multi-disciplinary endocrine team indications that a patient has MGDP. This could alter surgical strategy.

CONCLUSION

Biochemistry can provide diagnosis of PHPT but cannot reliably discriminate parathyroid pathology. Histopathology can aid diagnosis between MGPD and adenoma, but histological appearance can overlap. Multiple negative imaging modalities indicate that MGPD may be more likely than a single parathyroid adenoma, but the gold standard for diagnosis is still intraoperative identification during BNE. MGPD remains a difficult disease to both diagnose and treat.

Coherent Subcycle Optical Shock from a Superluminal Plasma Wake

We propose exploiting the superluminal plasma wake for coherent Cherenkov radiation by injecting a relativistic electron beam (REB) into a plasma with a slowly varying density up-ramp. Using three-dimensional particle-in-cell and far-field time-domain radiation simulations, we show that an isolated subcycle pulse is coherently emitted towards the Cherenkov angle by bubble-sheath electrons successively at the rear of the REB-induced superluminal plasma wake. A theoretical model based on a superluminal current dipole has been developed to interpret such coherent radiation, and agrees well with the simulation results. This radiation has ultrashort attosecond-scale duration and high intensity, and exhibits excellent directionality with ultralow angular divergence and stable carrier envelope phase. Its intensity increases with the square of the propagation length and its central frequency can be easily tuned over a wide range, from the far infrared to the ultraviolet.

Granular vortex spin-torque nano oscillator for reservoir computing

In this paper, we investigate the granularity in the free layer of the magnetic tunnel junctions (MTJ) and its potential to function as a reservoir for reservoir computing where grains act as oscillatory neurons while the device is in the vortex state. The input of the reservoir is applied in the form of a magnetic field which can pin the vortex core into different grains of the device in the magnetic vortex state. The oscillation frequency and MTJ resistance vary across different grains in a non-linear fashion making them great candidates to be served as the reservoir's outputs for classification objectives. Hence, we propose an experimentally validated area-efficient single granular vortex spin-torque nano oscillator (GV-STNO) device in which pinning sites work as random reservoirs that can emulate neuronal functions. We harness the nonlinear oscillation frequency and resistance exhibited by the vortex core granular pinning of the GV-STNO reservoir computing system to demonstrate waveform classification.

Dosimetric Advantages of Online Adaptative Radiotherapy for Cervical Cancer on 1.5T MR-Linac

PURPOSE/OBJECTIVE(S)

Online adaptative radiotherapy (ART) strategy can be applied to account for inter-fraction organ motion while limiting organ at risk (OAR) dose. This study aims to evaluate tumor target and OARs inter- and intrafraction motion using online MRI during the full course of MR-Linac radiotherapy fractions. Furthermore, quantify the dosimetric consequences of online adaptative compared with non-adaptative radiotherapy (non-ART) in cervical cancer.

MATERIALS/METHODS

Six cervix cancer patients were treated with 150 fractions on the 1.5 T Unity MR-Linac. Each fraction, pre-treatment MRI scans were obtained at the start of every treatment session, and post-treatment MRI scans were obtained at the end of every treatment session. A total 300 MR images were included in this study and the CTV, bladder and rectum were delineated on each MRI by the same radiation oncologist. The inter-fraction and intrafraction changes of contours were evaluated by dice similarity coefficient (DSC), Hausdorff distance (HD), volume difference (ΔV). The reference treatment plans were generated using step-and-shoot IMRT and utilized 9 beam groups on original CT. Then, the online adaptative treatment plans were obtained by re-optimizing based on the contours on daily pre-treatment MRI by "adapt to shape" workflow using the same beam parameters and optimization objectives from the reference plans. Non-ART plans for each patient were generated by recalculating the dose from the reference plans on daily online MRI by "adapt to position" workflow. CTV coverage and OARs constraints were used to compare ART and non-ART plans.

RESULTS

The results showed that large inter-fraction anatomical changes limited the efficacy of radiation therapy (CTV: DSC: 0.89±0.03, HD: 20.83±5.05mm, ΔV: 1.21%±5.44%; Bladder: DSC: 0.68±0.18, HD: 30.58±15.75mm, ΔV: -10.17%±61.19%; Rectum: DSC: 0.69±0.09, HD: 22.98±12.03mm, ΔV: 21.01%±20.59%).The intrafraction anatomical changes were smaller (CTV: DSC: 0.96±0.01, HD: 8.85±3.54mm, ΔV: -0.64%±1.90%; Bladder: DSC: 0.90±0.07, HD: 14.62±9.56mm, ΔV: 19.83%±21.71%; Rectum: DSC: 0.98±0.04, HD: 2.90±4.27mm, ΔV: 0.13%±5.04%) . Non-ART showed inadequate primary CTV coverage in 30% of the daily fractions. Online adaptative plans improved CTV coverage significantly (p<0.001) to 99%. Compared with non-ART, online ART decreased the fraction dose to bladder and rectum indicated by significant (p<0.001) improvements for daily D50%, D2% and Dmean.

CONCLUSION

In cervical cancer radiotherapy, a non-adaptive strategy led to inadequate target coverage for individual patients. Online adaptative radiotherapy corrected for day-to-day anatomical variations and resulted in adequate target coverage in all fractions. The dose to rectum and bladder was decreased significantly when applying online adaptative radiotherapy.

Genomic insights into linezolid-resistant Enterococci revealed its evolutionary diversity and poxtA copy number heterogeneity

OBJECTIVES

This study aimed to determine the molecular mechanisms of linezolid-resistant enterococci (LRE) in swine slaughterhouses in China and apply the "One Health" perspective to analyse the evolutionary dynamics of poxtA-positive E. faecium in clinical and non-clinical settings worldwide.

METHODS

The phenotypic and genomic characteristics of multiple LRE isolates were systematically investigated using antimicrobial susceptibility testing, transfer assays, evolutionary experiments, quantitative RT-PCR assays, whole-genome sequencing, and bioinformatics analyses.

RESULTS

Swine faeces served as a significant reservoir for LRE isolates, and optrA and poxtA were the primary contributors to linezolid resistance. Co-occurrence network analysis revealed a significant interconnection between optrA and several other ARGs. The poxtA copy number heterogeneity and polymorphism were initially observed in E. faecium parental and evolved isolates. The poxtA-carrying tandem repeat region exhibits high mobility and has undergone extensive duplication owing to linezolid pressure. The poxtA copy number varies from four copies on the plasmid of E. faecium IC25 to 11 copies on the plasmid and six copies on the chromosome in the evolved isolate IC25-50_poxtA. Furthermore, phylogenetic analysis of 185 poxtA-positive E. faecium strains worldwide found that one isolate from a French patient in 2018 shared only two SNPs with CC17 E. faecium isolates IC25 and IC7-2 from this study, highlighting the potential global transmission of CC17 poxtA-positive E. faecium between humans and animals.

CONCLUSION

This study identified amplification of poxtA as a response of E. faecium to linezolid pressure. Phylogenetic analysis shed light on the potential global transmission of hospital-associated CC17 poxtA-positive E. faecium in clinical and non-clinical settings.

Dynamic evolution and transmission of a blaNDM-1-bearing fusion plasmid in a clinical Escherichia coli

Plasmids are the main driving forces for the rapid dissemination of blaNDM-1. In recent years, blaNDM-1-carrying fusion plasmids have been frequently reported. However, the evolutionary patterns of blaNDM-1-carrying fusion plasmids remain largely unknown. Herein, we reported a blaNDM-1-bearing fusion plasmid pZX35-269k possessing IncFII and IncA/C2 replicons from clinical ST349 E. coli 13ZX35. The backbone of pZX35-269k was structurally unstable, which was manifested in different types of structural dissociation during conjugation and passage, thereby forming various daughter plasmids. Moreover, the same events were observed in the clinical setting as well. We found that pZX35-269k exhibited highly identical to two plasmids (pZX30-70k and pZX30-192k) in 13ZX30, both of which were isolated from the same hospital. Sequence analysis highlighted that two plasmids in 13ZX30 evolved from pZX35-269k through homologous recombination of a 4856-bp fragment. Collectively, this study confirmed the transmission and structural evolution of a blaNDM-1-bearing fusion plasmid in both laboratory and clinical settings, and provided clear evidence of plasmid spread and evolution in clinical settings. Such versatile plasmids may represent a potential risk for the public health.

Effect of Anemia on Tumor Response to Preoperative Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer

PURPOSE/OBJECTIVE(S)

Preoperative neoadjuvant chemoradiotherapy (nCRT) and total rectal mesenteric resection (TME) are the primary treatment options for locally advanced rectal cancer (LARC), but their efficacy varies. This study aimed to investigate the impact of anemia on the tumor response of patients with LARC receiving preoperative neoadjuvant chemoradiotherapy.

MATERIALS/METHODS

This study was a retrospective analysis of clinical and pathological data from patients with LARC who underwent nCRT and TME from January 2019 to May 2022 at a single institution. The tumor response was evaluated based on the tumor regression grade (TRG) and T-stage change of the primary tumor. Hemoglobin concentration was measured and graded to determine the presence of anemia. Anemia was categorized into four groups based on the hemoglobin levels: mild anemia (90-120 g/L), moderate anemia (60-90 g/L), severe anemia (30-60 g/L), and extreme anemia (less than 30 g/L). Finally, tumor response was quantified histologically using the AJCC 8th edition tumor regression grading system for rectal cancer and pre- and post-treatment T-grading.

RESULTS

A total of 88 patients with LARC who received nCRT and TME were included in the study, with 17 females and 71 males. Of these patients, 9 were moderately anemic and 37 were mildly anemic. The radiation therapy regimen was administered at a dose of 1.8-2 Gy per fraction, five times a week, for a total dose of 45-50.4 Gy. Capecitabine chemotherapy was also administered orally (825 mg/m2, twice a day) on the days of radiation therapy. Other chemotherapy regimens included XELOX and mFOLFOX6. The TRG was significantly different in anemic patients compared to non-anemic patients (P = 0.039). Only 2 out of 46 anemic patients (4%) showed an excellent response (TRG0), while 8 out of 42 non-anemic patients (19%) showed an excellent response (p = 0.043). There was also a significant difference in the incidence of anemia between cT3 and cT4 stages (p = 0.048), with 44% of cT3 patients and 67% of cT4 patients being anemic. The number of patients with poor response (TRG2-3) decreased as the degree of anemia decreased, but no significant difference was found. The incidence of TRG3 was 11% in patients with moderate anemia and 7% in non-anemic patients (P = 0.863). There was no significant difference in postoperative pathological T-stage between anemic and non-anemic patients. 89% of anemic patients had a pathological stage of ypT3 or less after chemoradiotherapy, while 95% of non-anemic patients did (P = 0.167). The pre- and post-treatment pathological staging did not significantly differ between anemic and non-anemic patients. 67% of anemic patients had descending tumors, while 59.5% of non-anemic patients had descending tumors (p = 0.509).

CONCLUSION

Patients with LARC who have normal hemoglobin concentrations during nCRT have better tumor regression compared to patients with anemia. Additionally, the incidence of anemia was higher among patients with advanced T-stage prior to treatment.

Inter-fractional Assessment during MR-guided Online Adaptive Radiotherapy for Glioblastoma

PURPOSE/OBJECTIVE(S)

Magnetic resonance image (MRI) guided radiation therapy has the potential to improve outcomes for glioblastoma by adapting to tumor changes during radiation therapy. This study aimed to assess the feasibility and potential benefits of MR-guided online adaptive radiotherapy (MRgOART) for patients with glioblastoma.

MATERIALS/METHODS

Twenty consecutive patients with glioblastoma were treated with MRgOART of 60 Gy in 30 fractions by the 1.5 T MR-Linac. The MRgOART fractions employed daily MR scans and the contours were utilized to create each adapted plan. The gross tumor volume (GTV) and clinical target volume (CTV) were delineated on MRI of pre-treatment simulation (Fx0) and all fractions (Fx1, Fx2, Fx3 ... Fx30) to evaluate the inter-fractional changes. These changes were quantified using absolute/relative volume (∆V), Dice similarity coefficient (DSC) and Hausdorff distance (HD) metrics. The reference treatment plans were generated using step-and-shoot IMRT and utilized 7-9 beam groups on original CT. Before the treatment, a synthetic CT (sCT) quality assurance (QA) process was performed to assess the dose accuracy of bulk relative electron density (rED) assignment for online MRI based treatment plan in terms of gamma analysis, point dose comparison and dose volume histogram (DVH) parameters. Then, the online adaptative treatment plans were obtained by re-optimizing based on the contours on daily pre-treatment MRI by "adapt to shape" workflow. Non-adaptive plans for each patient were generated by recalculating the dose from the reference plans on daily online MRI by "adapt to position" workflow. GTV and CTV coverage and organ at risk (OAR) constraints were used to compare non-adaptive and adaptive plans.

RESULTS

For both criteria, the 1%/1mm (98.58%±0.15%) and 2%/2mm (99.88%±0.18%) gamma passing rate results were always clinically acceptable in sCT QA process. The differences on point dose and DVH parameters between the plans based on sCT and original CT were less than 1%. A total of 20 patients with 600 fractions were evaluated. The results showed that large inter-fractional changes for GTV limited the efficacy of radiation therapy (DSC: 0.78±0.08, HD: 20.94±3.64mm, ∆V: 2.92%±6.36%). The inter-fractional CTV changes were smaller (DSC: 0.91±0.04, HD: 15.31±3.09mm, ∆V: 1.41%±1.29%). GTV coverage of non-adaptive plans was below the prescribed coverage in 228/600 fractions (38%), with 90 (15%) failing by more than 10%. For CTV coverage of non-adaptive plans, the changes were less than 5%. Online adaptative plans improved GTV and CTV coverage significantly (p<0.001) to 99%. The adaptive plans also had lower dose to whole brain than non-adaptive plans (p<0.001).

CONCLUSION

Significant inter-fractional tumor changes could be found during radiotherapy in patients with glioblastoma treated by the 1.5 T MR-Linac. Daily MR-guided re-optimization of treatment plans corrected for day-to-day anatomical variations and resulted in adequate target coverage in all fractions.

Exploring the TRP channel superfamily: research hotspots and development trends from function to disease

OBJECTIVE

Transient receptor potential (TRP) channels are a superfamily of permeable cation channels activated by various mechanisms and play a role in nearly all types of sensory signal transduction. In academia, few have comprehensively discussed the research status of TRP channels. This study aims to summarize the knowledge structure and research hotspots of TRP channels using bibliometrics.

MATERIALS AND METHODS

TRP channel-related publications from 2003 to 2022 were searched in the Web of Science Core Collection (WoSCC) database. VOSviewer was used for the bibliometric analysis of the literature.

RESULTS

We included 12,242 articles from 102 countries, primarily from the United States, China, and Japan. Our research indicates that the number of publications related to TRP channels has increased annually from 2003 to 2022. The leading research institutions are KU Leuven, Harvard University, and the Chinese University of Hong Kong. The Journal of Biological Chemistry is the foremost in this field. The main research topics include the structure and function of TRP channels, their role in pathogenesis, and potential therapeutic strategies for diseases such as pain and respiratory diseases. Among these, "transient receptor potential vanilloid 1 (TRPV1)", "transient receptor potential ankyrin 1 (TRPA1)", "TRPV4", "pain", and "therapy" are emerging research hotspots.

CONCLUSIONS

This study offers a comprehensive summary of the current research status and development trends of TRP channels and pinpoints the research hotspots in this field. It not only aids individuals interested in TRP channel-related research in quickly gauging the trends but may also guide the future research directions of researchers.

Adaptive Auto-Segmentation for MRI-Guided Online Adaptive Radiotherapy of Cervical Carcinoma

PURPOSE/OBJECTIVE(S)

Accurate and efficient delineation of organs and targets on session images is critical in MRI-guided online adaptive radiotherapy (MRgOART). This study proposes a registration-guided deep learning image segmentation framework to assist online delineation of cervical carcinoma.

MATERIALS/METHODS

A total of 300 T2-weighted MR images were acquired for patients with cervical carcinoma treated by a 1.5T Unity MR-Linac. The CTV, bladder, rectum, pelvic bone and femoral joints were delineated on each MRI by the same radiation oncologist. To overcome these obstacles to online MRI segmentation, we propose a registration-guided DL (RgDL) segmentation framework that integrates image registration algorithms and DL segmentation models. Firstly, the DL segmentation model was trained using nnU-net. Then, for each treatment fraction, the deformable image registration (DIR) algorithm generates initial contours from previous treatment fraction, which were used as guidance by DL model to obtain the accurate current segmentation. The segmentation accuracy of alone DIR, DL and RgDL were evaluated by dice similarity coefficients (DSC) and other distance-based metrics.

RESULTS

Compared to the baseline approaches using the DIR and the DL alone, RgDL achieved a DSC of 91.12% on CTV, higher than DIR and DL alone by 15.54% and 10.13%. The DSC of RgDL were improved to 95.58%, 93.65%, 87.8% and 94.84% for bladder, pelvic bone, rectum and femoral joints, higher than DIR and DL alone by 9.61% on average.

CONCLUSION

The proposed adaptive auto-segmentation method can achieve accurate and efficient segmentation and potentially overcome these obstacles to MRgOART.

Priority list of potential endocrine-disrupting chemicals in food chemical contaminants: a docking study and in vitro/epidemiological evidence integration

Diet is an important exposure route of endocrine-disrupting chemicals (EDCs), but many unfiltered potential EDCs remain in food. The in silico prediction of EDCs is a popular method for preliminary screening. Potential EDCs in food were screened using Endocrine Disruptome, an open-source platform for inverse docking, to predict the binding probabilities of 587 food chemical contaminants with 18 human nuclear hormone receptor (NHR) conformations. In total, 25 contaminants were bound to multiple NHRs such as oestrogen receptor α/β and androgen receptor. These 25 compounds mainly include pesticides and per- and polyfluoroalkyl substances (PFASs). The prediction results were validated with the in vitro data. The structural features and the crucial amino acid residues of the four NHRs were also validated based on previous literature. The findings indicate that the screening has good prediction efficiency. In addition, the epidemic evidence about endocrine interference of PFASs in food on children was further validated through this screening. This study provides preliminary screening results for EDCs in food and a priority list for in vitro and in vivo research.

Dosimetric Analysis of CBCT-Based Weekly Online Adaptive Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Anatomic and geometric changes are common during a radiotherapy course amongst patients receiving conventional fractionated radiotherapy for locally advanced non-small cell lung cancer (LA-NSCLC). These changes may cause significant deviation from initial reference plan resulting in over-treatment of normal tissue or under-coverage of the target. Cone-beam computed tomography (CBCT)-based online adaptive radiotherapy (ART) platforms allow for response to these changes and is being increasingly used in the clinic though less so for intrathoracic disease. We hypothesized weekly CBCT-ART would improve target coverage and decrease dose to organs at risk (OAR) in patients with LA-NSCLC.

MATERIALS/METHODS

Data was collected from a prospective registry of 23 LA-NSCLC patients treated to 60 Gy in 30 fractions with CBCT-ART between June 2021 and December 2022. For weekly ART (Wk-ART), online plan adaptation started on week two. The adapted plan was then used to treat patients with image guidance until the next ART. For comparison, doses were recalculated with the initial reference plan on the SCT with updated contours to derive non-adapted (non-ART) dosimetry for each week. The final dosimetric parameters were obtained by averaging weekly coverage (ITV, PTV) and critical OAR (Lung, esophagus, heart, spinal cord) doses for non-ART and weekly ART treatments respectively for each patient. Paired student t-test was performed to compare the dosimetric parameters between non-ART and Wk-ART.

RESULTS

We observed an average 29% ± 19% (median: 26%) reduction in ITV volume through the radiotherapy course, with 48% (11/23) of patients showing >30% reduction. Most significant volume reductions (16%) were observed between the third and fourth adaptation. Weekly ART showed significant (p<1×10-3) improvements in ITV and PTV coverage, and showed improved clinically relevant lung, esophageal, cardiac, and lung dosimetry (Table 1), especially in the later stages of treatment when the tumor showed significant shrinkage. The average time from contour review to quality assurance completed is 8.5±1.2 min.

CONCLUSION

CBCT-ART provides robust ART plan quality and efficient workflow. There are significant improvements in target coverage and OAR sparing in LA-NSCLC treated with weekly CBCT-ART and these are driven by the significant volume reduction of the ITV throughout treatment course.

The Role of CT-Based Radiomics Nomogram in Differential Diagnosis of Immune Checkpoint Inhibitor-Related Pneumonitis from Radiation Pneumonitis for Patients with ESCC

PURPOSE/OBJECTIVE(S)

The combination of immunotherapy and chemoradiotherapy has widely used for patients with esophageal squamous cell carcinoma (ESCC) and induced treatment-related adverse effects, particularly immune checkpoint inhibitor-related pneumonitis (CIP) and radiation pneumonitis (RP). The aim of this study is to differentiate between CIP and RP by the CT radiomics and clinical or radiological parameters.

MATERIALS/METHODS

A total of 76 ESCC patients with pneumonitis were enrolled in this retrospective study and divided into training dataset (n = 53) and validation dataset (n = 23). A total of 837 radiomics features were extracted from regions of interest (ROIs) based on the lung parenchyma window of CT images. A radiomics signature was constructed on the basis of the predictive features by the least absolute shrinkage and selection operator (LASSO). A logistic regression was applied to develop radiomics nomogram. Receiver operating characteristics (ROC) curve and area under the curve (AUC) were applied to evaluate the performance of pneumonitis etiology identification.

RESULTS

No significant difference was detected between training dataset and validation dataset. The radiomics signature which was made up of four radiomics features shown a favorable performance on differentiating between CIP and RP with the α-binormal-based and empirical AUC = 0.831 and 0.843. Patients with RP had a close relationship with location (p = 0.003) and shape of lesions (p = 0.002). The nomogram that combined with radiomics signature and clinical factors improved the classifying performance on discrimination in the training dataset (AUCαbin = 0.963 and AUCemp = 0.964). The results were verified in the validation dataset with AUC = 0.967 and 0.964.

CONCLUSION

CT-based radiomics features have potential values for differentiating between patients with CIP and RP. Addition of bilateral changes and sharp border produced superior model performance on classifying, which could be a useful method to improve related clinical decision-making.

Influence of Eyes Movement on Lens Dose during MR-Guided Radiotherapy for Brain Tumor

PURPOSE/OBJECTIVE(S)

Modern radiotherapy techniques achieve highly conformal target doses while avoiding organs at risk such as lens. The magnitude of eyes movement and its influence on lens dose is unclear. The lens dose is relevant for cataract formation. This study aims to evaluate the movement-range of lens and its influence on dose distribution during MR-guided radiotherapy for brain cancer patients.

MATERIALS/METHODS

Fifty patients with brain cancer who were treated with MR-guided radiotherapy on 1.5 T MR-Linac were included in this study. All patients underwent a pre-treatment MRI and post-treatment MRI for each fraction. The eyes and lens were delineated on each MR image by a radiation oncologist. The reference treatment plans based original CT were recalculated on each MRI by "adapt to position" workflow. Then, we created planning risk volume (PRV) for lens by adding population margin and reoptimized the reference plans to evaluate the dose changes for lens. Inter-fraction and intrafraction variability for eyes and lens were evaluated with the Dice similarity coefficient (DSC), the Hausdorff distance (HD) and mean distance to agreement (MDA). Differences in daily dose (Dmax and Dmean) for eyes and lens were assessed.

RESULTS

A total of 300 MR images were analyzed in this study. The eyes motion was observed (minimum DSC: 0.57; maximum HD: 10.53; maximum MDA: 3.13). And the obvious lens motion also was found (minimum DSC: 0.01; maximum HD: 10.78; maximum MDA: 5.68). The maximum dose changes for eyes were up to 34.1% and the mean dose changes were up to 18.1%. The maximum dose changes for lens were up to 97.9% and the mean dose changes for eyes were up to 89%. When the reoptimized plans were generated by PRV lens, the dose changes were decreased nearly to 0.

CONCLUSION

Eyes movements in all radiotherapy fractions result in higher lens doses and potentially increase cataract formation rate. Adding margin expansions in treatment planning, to account for eyes motion, is the feasible approach to limit lens dose.