Drought priming-induced stress memory improves subsequent drought or heat tolerance via activation of γ-aminobutyric acid-regulated pathways in creeping bentgrass

Recurrent drought can induce stress memory in plants to induce tolerance to subsequent stress, such as high temperature or drought. Drought priming (DP) is an effective approach to improve tolerance to various stresses; however, the potential mechanism of DP-induced stress memory has not been fully resoved. We examined DP-regulated subsequent drought tolerance or thermotolerance associated with changes in physiological responses, GABA and NO metabolism, heat shock factor (HSF) and dehydrin (DHN) pathways in perennial creeping bentgrass. Plants can recover after two cycle of DP, and DP-treated plants had significantly higher tolerance to subsequent drought or heat stress, with higher leaf RWC, Chl content, photochemical efficiency, and cell membrane stability. DP significantly alleviated oxidative damage through enhancing total antioxidant capacity in response to subsequent drought or heat stress. Endogenous GABA was significantly increased by DP through activating glutamic acid decarboxylase activity and inhibiting GABA transaminase activity. DP also enhanced accumulation of NO, depending on NOS activity, under subsequent drought or heat stress. Transcript levels of multiple transcription factors, heat shock proteins, and DHNs in the HSF and DHN pathways were up-regulated by DP under drought or heat stress, but there were differences between DP-regulated heat tolerance and drought tolerance in these pathways. The findings indicate that under recurrent moderate drought, DP improves subsequent tolerance to drought or heat stress in relation to GABA-regulated pathways, providing new insight into understanding of the role of stress memory in plant adaptation to complex environmental stresses.

Microbiomes detected by cerebrospinal fluid metagenomic next-generation sequencing among patients with and without HIV with suspected central nervous system infection

BACKGROUND

Opportunistic infections in the central nervous system (CNS) can be a serious threat to people living with HIV. Early aetiological diagnosis and targeted treatment are crucial but difficult. Metagenomic next-generation sequencing (mNGS) has significant advantages over traditional detection methods. However, differences in the cerebrospinal fluid (CSF) microbiome profiles of patients living with and without HIV with suspected CNS infections using mNGS and conventional testing methods have not yet been adequately evaluated.

METHODS

We conducted a retrospective cohort study in the first hospital of Changsha between January 2019 and June 2022 to investigate the microbiomes detected using mNGS of the CSF of patients living with and without HIV with suspected CNS infections. The pathogens causing CNS infections were concurrently identified using both mNGS and traditional detection methods. The spectrum of pathogens identified was compared between the two groups.

RESULTS

Overall, 173 patients (140 with and 33 without HIV) with suspected CNS infection were enrolled in our study. In total, 106 (75.7%) patients with and 16 (48.5%) patients without HIV tested positive with mNGS (p = 0.002). Among the enrolled patients, 71 (50.7%) with HIV and five (15.2%) without HIV tested positive for two or more pathogens (p < 0.001). Patients with HIV had significantly higher proportions of fungus (20.7% vs. 3.0%, p = 0.016) and DNA virus (59.3% vs. 21.2%, p < 0.001) than those without HIV. Epstein-Barr virus (33.6%) was the most commonly identified potential pathogen in the CSF of patients living with HIV using mNGS, followed by cytomegalovirus (20.7%) and torque teno virus (13.8%). The top three causative pathogens identified in patients without HIV were Streptococcus (18.2%), Epstein-Barr virus (12.1%), and Mycobacterium tuberculosis (9.1%). In total, 113 patients living with HIV were diagnosed as having CNS infections. The rate of pathogen detection in people living with HIV with a CNS infection was significantly higher with mNGS than with conventional methods (93.8% vs. 15.0%, p < 0.001).

CONCLUSION

CSF microbiome profiles differ between patients living with and without HIV with suspected CNS infection. mNGS is a powerful tool for the diagnosis of CNS infection among people living with HIV, especially in those with mixed infections.

Banxia-Houpu decoction inhibits iron overload and chronic intermittent hypoxia-induced neuroinflammation in mice

ETHNOPHARMACOLOGICAL RELEVANCE

The Banxia-Houpu decoction (BHD), a renowned prescription documented in the Chinese medical book "The Synopsis of the Golden Chamber," has been proven to effectively mitigate inflammation within the central nervous system. Previous studies have demonstrated the efficacy of BHD in ameliorating symptoms in patients with obstructive sleep apnea (OSA). Nevertheless, the precise mechanisms and comprehensive effects of BHD on central system injury in OSA models have not been fully investigated.

AIM OF THE STUDY

To investigate whether BHD could inhibit neuroinflammation to decrease iron-induced neurotoxic injury in CIH mice.

MATERIALS AND METHODS

C57BL/6N mice were divided into the Con, CIH, and BHD groups. Mice were exposed to CIH (21%-5% FiO2, 3 min/cycle, 8 h/d), and BHD was administered by gavage (3.51, 7.01, and 14.02 g/kg). The polarization of microglia, inflammatory factors, hepcidin, and brain iron levels were determined.

RESULTS

The administration of BHD at a dosage of 7.01 g/kg demonstrated a significant reduction in neurobehavioral abnormalities, neuronal damage, and degeneration caused by CIH. BHD exhibited the ability to inhibit the transition of microglial polarization from M2 to M1 by upregulating CD163 expression and downregulating iNOS levels. Furthermore, BHD decreased pro-inflammatory factor levels and increased anti-inflammatory factor levels. Additionally, BHD was found to decrease hepcidin expression in astrocytes through the TLR4/MyD88/NF-κB signaling pathway. BHD reduced the total and neuronal iron levels by elevating FPN1 and reducing TfR1 levels. BHD exhibited positive effects on synapse and synaptic spine abnormalities, as well as an increase in the Bcl-2/Bax ratio, thereby mitigating neuronal damage induced by CIH.

CONCLUSIONS

Based on these findings, BHD holds potential as a therapeutic intervention for neural damage injuries, which offers a theoretical foundation for the treatment of patients with OSA in clinical.

Acetylation of MOB1 mediates polyphyllin II-reduced lysosome biogenesis in breast cancer by promoting the cytoplasmic retention of the YAP/TFEB coactivator complex

BACKGROUND

Autophagy‒lysosome abnormalities are associated with the malignant progression of cancer. Transcription factor EB (TFEB) is the master transcriptional regulator of the autophagy‒lysosome machinery, and its abnormal activity is associated with autophagy-lysosome dysfunction. Polyphyllin II (PPII), an active steroidal saponin isolated from the rhizomes of Paris polyphylla, has been demonstrated to have antitumor activity.

PURPOSE

Here, we explored the antitumor activity of PPII in breast cancer (BC) and further clarified its mechanism.

METHODS

Autophagosome was detected by transmission electron microscopy, an autophagy indicator system, and western blot. The effect of PPII on lysosomal activity was evaluated by flow cytometry, a lysosomal cathepsin activity assay, and acridine orange staining. The effect of PPII on the signaling pathway was evaluated by Western blot, gene expression measurement, gene alterations. The binding of PPII and MOB1 was examined through a drug affinity responsive target stability assay. The pharmacokinetic parameters of PPII were evaluated in Sprague-Dawley rats.

RESULTS

PPII exhibits therapeutic potential in BC by inducing the accumulation of autophagosome. PPII promotes the cytoplasmic retention of YAP/TFEB, which is responsible for the accumulation of autophagosome in BC. PPII activates Hippo signaling to promote cytoplasmic retention of YAP. PPII activates Hippo signaling by accelerating acetylation of MOB1 through a direct binding interaction.

CONCLUSION

Taken together, these results confirm that acetylation of MOB1 mediates PPII-induced autophagosome accumulation in BC by promoting cytoplasmic retention of the YAP/TFEB coactivator complex. PPII is expected to be a drug candidate for the treatment of BC based on lysosomal biosynthesis.

Norovirus outbreaks in hospitals in China: a systematic review

BACKGROUND

Norovirus outbreaks in hospitals can potentially impair patient care and result in significant financial expenses. There is currently limited information on hospital norovirus outbreaks in the Chinese mainland.

AIM

To systematically review the published literature to describe the characteristics of norovirus outbreaks in Chinese mainland hospitals to facilitate prompt identification and control of outbreaks.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis standards. Databases including PubMed, Web of Science, and Chinese Journals Online databases (China National Knowledge Infrastructure (CNKI), Chinese Wan Fang digital database (WANFANG) were searched from inception to July 18th, 2022.

FINDINGS

A total of 41 norovirus Chinese hospital outbreaks occurring before July 18th, 2022 were reported in 32 articles. Most reported outbreaks were from Shanghai and Beijing, and occurred in December and January. Cases were mainly adults. The male:female ratio was 1.22:1. The majority of cases in norovirus outbreaks were hospitalized patients (56.82%); medical staff were affected in 15 outbreaks. Norovirus outbreaks occurred in both private and public hospitals, and in secondary and tertiary care centres, and occurred mainly in internal medicine and geriatric departments. Person-to-person transmission was the primary transmission mode and GII was more prevalent.

CONCLUSION

Norovirus outbreaks in hospitals can affect both patients and healthcare workers, sometimes causing serious financial losses. In order to have a more complete understanding of the disease burden caused by norovirus outbreaks, surveillance needs to be established in hospitals.

Preparation and Photovoltaic Performance of a Composite TiO2 Nanotube Array/Polyaniline UV Photodetector

TiO2 has great potential for application in UV photodetectors due to its excellent photoelectric response. In this work, composite nanomaterials of TiO2 nanotube arrays (TiO2 NTAs) and polyaniline (PANI) were successfully prepared on titanium sheets using an anodic oxidation electrochemical method. The results showed that the TiO2 NTA/PANI composite materials had excellent UV photosensitivity and responsiveness and good stability and reproducibility. This was mainly attributed to the p-n heterostructure formed inside the TiO2 NTA/PANI composites that hindered the recombination of photogenerated electron-hole pairs and improved their utilization of UV light. This work provides a theoretical basis for the application of metal oxides in UV photodetectors, which is important for the development of UV photodetectors.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Sculponeatin A promotes the ETS1-SYVN1 interaction to induce SLC7A11/xCT-dependent ferroptosis in breast cancer

BACKGROUND

E26 transformation specificity-1 (ETS1) is a transcription factor that is overexpressed in breast cancer (BC) and promotes tumor progression. Sculponeatin A (stA), a new diterpenoid extracted from Isodon sculponeatus, has no reported antitumor mechanism.

PURPOSE

Here, we explored the antitumor activity of stA in BC and further clarified its mechanism.

METHODS

Ferroptosis was detected by flow cytometric, glutathione, malondialdehyde, and iron determination assays. The effect of stA on the upstream signaling pathway of ferroptosis was detected by Western blot, gene expression, gene alterations and other approaches. The binding of stA and ETS1 was examined through a microscale thermophoresis assay and a drug affinity responsive target stability assay. An in vivo mouse model experiment was performed to evaluate the therapeutic and potential mechanism of stA.

RESULTS

stA exhibits therapeutic potential in BC by inducing SLC7A11/xCT-dependent ferroptosis. stA decreases the expression of ETS1, which is responsible for xCT-dependent ferroptosis in BC. stA inhibits the transcriptional expression of xCT by directly binding to the ETS domain of the ETS1 protein. In addition, stA promotes proteasomal degradation of ETS1 by triggering ubiquitin ligase synoviolin 1 (SYVN1)-mediated ubiquitination. The K318 site of ETS1 mediates ubiquitination of ETS1 by SYVN1. In a mouse model, stA inhibits tumor growth without causing obvious toxicity.

CONCLUSION

Taken together, the results confirm that stA promotes the ETS1-SYVN1 interaction to induce ferroptosis in BC mediated by ETS1 degradation. stA is expected to be used in research of candidate drugs for BC and drug design based on ETS1 degradation.

Molecular characterization of coxsackievirus B5 from the sputum of pneumonia children patients of Kunming, Southwest China

BACKGROUND

CVB5 can cause respiratory infections. However, the molecular epidemiological information about CVB5 in respiratory tract samples is still limited. Here, we report five cases in which CVB5 was detected in sputum sample of pneumonia children patients from Kunming, Southwest China.

METHODS

CVB5 isolates were obtained from sputum samples of patients with pneumonia. Whole-genome sequencing of CVB5 isolates was performed using segmented PCR, and phylogenetic, mutation and recombination analysis. The effect of mutations in the VP1 protein on hydration were analyzed by Protscale. The tertiary models of VP1 proteins were established by Colabfold, and the effect of mutations in VP1 protein on volume modifications and binding affinity were analyzed by Pymol software and PROVEAN.

RESULTS

A total of five CVB5 complete genome sequences were obtained. No obvious homologous recombination signals comparing with other coxsackie B viruses were observed in the five isolates. Phylogenetic analysis showed that the five CVB5 sputum isolates were from an independent branch in genogroup E. Due to the mutation, the structure and spatial of the VP1 protein N-terminus have changed significantly. Comparing to the Faulkner (CVB5 prototype strain), PROVEAN revealed three deleterious substitutions: Y75F, N166T (KM35), T140I (KM41). The last two of the three deleterious substitutions significantly increased the hydrophobicity of the residues.

CONCLUSIONS

We unexpectedly found five cases of CVB5 infection instead of rhinoviruses infection during our routine surveillance of rhinoviruses in respiratory tract samples. All five patients were hospitalized with pneumonia symptoms and were not tested for enterovirus during their hospitalization. This report suggests that enterovirus surveillance in patients with respiratory symptoms should be strengthened.

Predictive value of peritumour radiomics in the diagnosis of benign and malignant pulmonary nodules with halo sign

AIM

To evaluate peritumour radiomics in predicting benign and malignant pulmonary nodules with halo sign.

MATERIALS AND METHODS

In this retrospective study, 305 pulmonary nodules with halo sign (benign, 120; adenocarcinoma, 185) were collected. Manual segmentation was used to mark the gross tumour volume (GTV) and the peritumour volume (PTV) was established by uniform dilation (1 cm) of the tumour area in three dimensions. The GTV and PTV radiomic features were combined to produce the gross tumour and peritumour volume (GPTV). The minimum-redundancy maximum-relevance (mRMR) feature ranking method and least absolute shrinkage and selection operator (LASSO) algorithm were used to eliminate redundant radiomic features. Predictive models combined with clinical features and radiomic signatures were established. Multivarible logistic regression analysis was used to establish the combined model and develop a nomogram. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive performance of the model.

RESULTS

In the testing cohort, the area under the ROC curve (AUC) of the GTV, PTV, and GPTV radiomic models was 0.701 (95% CI: 0.589-0.814), 0.674 (95% CI: 0.557-0.791) and 0.755 (95% CI: 0.643-0.867), respectively. The AUC of the nomogram model based on clinical and GPTV radiomic signatures was 0.804 (95% CI: 0.707-0.901).

CONCLUSION

The nomogram model based on clinical and GPTV radiomic signatures can better predict benign and malignant pulmonary nodules with halo signs, demonstrating that the model has potential as a convenient and effective auxiliary diagnostic tool for radiologists.

Recent progress in the biology and physiology of BMP-8a

PURPOSE

BMP-8a is a member of bone morphogenetic proteins (BMPs) and plays a regulatory role in human growth and development as a transcription regulator. This review aims to summarize the current research on the impact and mechanism of BMP-8a in female and male reproduction, formation and eruption of teeth, bone and cartilage development, tissue differentiation, disease occurrence, progression and prognosis.

METHODS

The phrases "BMP-8a," "BMPs," "regulator," "mechanism," "osteoblast," "cartilage," "cancer," "disease," and "inflammation" were searched in the PubMed database. The abstracts were evaluated, and a series of original publications and reviews were examined.

RESULTS

According to the search, BMP-8a affects the development of the uterus by inhibiting luteinization and plays an important role in late spermatogenesis. It is highly expressed in osteogenesis and differentially expressed in chondrogenesis. Furthermore, BMP-8a has a significant impact on the occurrence, development and prognosis of various diseases.

CONCLUSIONS

BMP-8a regulates important factors and pathways, such as SMAD2/3 and SMAD1/5/8, to promote or inhibit the developmental processes of human reproductive organs. BMP-8a is also a member of the BMP family of proteins that regulates chondrogenesis and osteogenesis. In addition to its osteoinductive capabilities, BMP-8a is involved in the progression of diverse cancers.

[Distribution and gene characteristics of H3, H4 and H6 subtypes of low pathogenic avian influenza viruses in environment related avian influenza viruses during 2014-2021 in China]

Objective: To analyze the characteristics of low pathogenic H3, H4 and H6 subtypes of avian influenza viruses in environment related avian influenza viruses in China from 2014 to 2021. Methods: Surveillance sites were located in 31 provinces, autonomous region and municipalities to collect environmental samples related to avian influenza, detect the nucleic acid detection of influenza A virus, isolate virus, deeply sequence, analyze pathogenicity related molecular sites, and determine the distribution and variation characteristics of common H3, H4 and H6 subtypes of avian influenza virus in different regions, places and sample types. Results: A total of 388 645 samples were collected. The positive rate of low pathogenic H3 (0.56‰) and H6 (0.53‰) was higher than that of H4 (0.09‰). The positive rate of H4 subtype virus in live poultry market was higher than that in other places, and the difference was statistically significant. The positive rate of H3 and H6 subtypes in sewage samples was higher than that in other samples, and the difference was statistically significant. The positive rate of H3, H4 and H6 viruses in the south was higher than that in the north, and the difference was statistically significant. December was the most active time for virus. The analysis of pathogenicity related molecular sites showed that H3, H4 and H6 subtypes of viruses combined with avian influenza virus receptors, and some gene sites related to increased pathogenicity had mutations. Conclusion: The H3, H4 and H6 subtypes of low pathogenic avian influenza viruses have a high isolation positive rate in the live poultry market and sewage. The distribution of the three subtypes of viruses has obvious regional and seasonal characteristics, and the genetic characteristics still show the feature of low pathogenic avian influenza.

[Ethoxysanguinarine directly targets CIP2A to inhibit proliferation and induce autophagy of SGC7901/DDP cells]

This study aims to investigate the effect of ethoxysanguinarine(Eth) on cisplatin(DDP)-resistant human gastric cancer cells and decipher the underlying mechanism. The human gastric cancer cell line SGC7901 and the DDP-resistant cell line SGC7901/DDP were used as the cell models. Western blot was employed to determine the expression levels of multidrug resistance-related proteins, and methyl thiazolyl tetrazolium(MTT) assay to detect the proliferation of SGC7901 and SGC7901/DDP cells exposed to DDP. After treatment with different concentrations of Eth, the proliferation of SGC7901 and SGC7901/DDP cells was detected by MTT assay, trypan blue exclusion assay, colony formation assay, and high-content imaging and analysis system. The apoptosis of SGC7901/DDP cells was detected by flow cytometry with Annexin V-FITC/PI staining. GFP-LC3 transfection was carried out to detect the effect of Eth on the autophagy of SGC7901/DDP cells. The expression levels of the multidrug resistance-related protein P-glycoprotein(P-gp), the apoptosis-related proteins [caspase-9, caspase-3, and poly(ADP-ribose) polymerase(PARP)], the autophagy-related protein light chain 3-Ⅱ(LC3-Ⅱ), the key effectors [mammalian target of rapamycin(mTOR), 70 kDa ribosomal protein S6 kinase(P70 S6 K), and 4 E binding protein 1(4 E-BP1)] of the mammalian target of rapamycin complex 1(mTORC1) signaling pathway, cancerous inhibitor of protein phosphatase 2A(CIP2A), and protein kinase B(Akt) were measured by Western blot. The mRNA level of CIP2A in the SGC7901/DDP cells exposed to Eth for 24 h was analyzed by RT-qPCR. After SGC7901/DDP cells were transfected with CIP2A expression vector pcDNA3.1-HA-CIP2A and treated with different concentrations of Eth, MTT assay was used to determine the prolife-ration of SGC7901/DDP cells and Western blot to detect the expression levels of related proteins. The interaction sites of Eth and CIP2A were predicted by molecular docking. The affinity between Eth and CIP2A was determined by drug affinity responsive target stability(DARTS) assay. The pharmacokinetic properties and drug-like activity of Eth were predicted by SwissADME. The results indicated that SGC7901/DDP cells were more sensitive to Eth than SGC7901 cells. Eth significantly inhibited proliferation and colony formation and changed the morphology, roundness, and area of SGC7901/DDP cells. Eth treatment caused the nucleus shrinking and significantly increased the apoptosis rate of the cells. Furthermore, Eth down-regulated the expression of caspase-9 and caspase-3 precursors and promoted the cleavage of PARP, which suggested that Eth induced the apoptosis of SGC7901/DDP cells. The GFP-LC3 in Eth-treated cells showed speckled aggregation. The up-regulated expression of LC3-Ⅱ by Eth indicated that Eth activated the autophagy of SGC7901/DDP cells. Eth down-regulated the expression of P-gp, the phosphorylation of mTOR, P70 S6K, and 4E-BP1, the expression of CIP2A, and the phosphorylation of Akt. Additionally, it increased the activity of PP2A, and had no significant effect on the expression of CIP2A in SGC7901/DDP cells. CIP2A overexpression antagonized the inhibition of cell proliferation and the activation of autophagy by Eth. Molecular docking suggested that Eth bound to CIP2A. The results of DARTS assay further proved the above binding effect. Eth has potential drug-like activity. The above results demonstrated that Eth inhibited the proliferation, induced the apoptosis, and activated the autophagy of SGC7901/DDP cells by targeting CIP2A and then down-regulating PP2A/mTORC1 signaling pathway. This study provided a new target for the treatment of cisplatin-resistant gastric cancer.

Associations between DAPT score and long-term mortality post PCI

Introduction

The dual antiplatelet therapy (DAPT) score was developed to identify patients more likely to derive benefit (score ≥2) or harm (score &lt;2) from DAPT beyond 1-year post PCI. There is no study which looked at the DAPT score and long term outcomes post PCI in Australia.

Purpose

We sought to examine long-term mortality after PCI by the DAPT score in patients treated with DAPT per local guidelines.

Methods

We examined data from the MIG PCI database from 2005 to 2018 in whom the DAPT score could be derived and grouped them as score ≥2 or &lt;2. Long-term mortality was assessed from National Death Index linkage. The primary endpoint was long-term mortality examined using survival analysis. Secondary endpoints included 30-day ischaemic outcomes and in-hospital major bleeding.

Results

Out of 27,740 patients in the study, 9,401 (33.9%) had DAPT score ≥2. They were younger and included more females and higher prevalence of renal impairment. DAPT score ≥2 patients had higher in-hospital major bleeding, 30-day mortality, MI and target vessel revascularisation. DAPT score ≥2 patients had lower long-term survival to 12 years (p&lt;0.001 for all).

Conclusion

A third of all-comer PCI patients had DAPT score ≥2 with greater short-term risk of ischaemic and bleeding outcomes, as well as long-term mortality. Theoretically, those with DAPT score ≥2 would benefit from longer duration of DAPT as ischaemic risk outweighs bleeding risk. However, given our finding of increased short-term bleeding risk and long-term mortality, dynamic bleeding risk assessment should be undertaken to guide pharmacotherapy strategies.

Funding Acknowledgement

Type of funding sources: None.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Preoperative prediction of the degree of differentiation of lung adenocarcinoma presenting as sub-solid or solid nodules with a radiomics nomogram

AIM

To develop and validate a radiomics nomogram for prediction of degree of differentiation in lung adenocarcinoma presenting as sub-solid or solid nodules.

MATERIALS AND METHODS

A total of 438 patients with histopathologically confirmed adenocarcinoma (248 non-poorly differentiated and 190 poorly differentiated) were divided into training cohort (n=235) and internal validation cohort (n=203) according to surgery sequence. Sixty patients form public TCIA dataset were selected for external validation. One thousand, two hundred and eighteen radiomics features were extracted from each volumetric region of interest and a least absolute shrinkage and selection operator logistic regression was applied to select meaningful radiomic features for building a radiomics score (Rad-score) model. A nomogram model incorporating the Rad-score and type was established after multivariable logistic regression. The discrimination efficiency, calibration efficacy, and clinical utility value of the nomogram were evaluated.

RESULTS

The Rad-score model could predict the differentiation degree of lung adenocarcinoma with an area under the curve (AUC) of 0.83 (95% confidence interval [CI]: 0.78-0.89) in the internal validation cohort. The AUC of the nomogram and radiographic model was 0.86 (95% CI: 0.80-0.91), 0.78 (95% CI: 0.72-0.84) in the internal validation cohort respectively. The AUC of the nomogram in the external validation cohort was 0.73 (95% CI: 0.58-0.88). Delong's test showed that the nomogram performed better than radiographic features alone (p=0.001).

CONCLUSIONS

The proposed radiomics nomogram has the potential to predict the differentiation degree of lung adenocarcinoma preoperatively.

[Relationship between preoperative inflammatory indexes and prognosis of patients with rectal cancer and establishment of prognostic nomogram prediction model]

Objective: To compare the prognostic evaluation value of preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and systemic immune-inflammation index (SII) in rectal cancer patients. Nomogram survival prediction model based on inflammatory markers was constructed. Methods: The clinical and survival data of 585 patients with rectal cancer who underwent radical resection in the First Affiliated Hospital of Xi'an Jiao tong University from January 2013 to December 2016 were retrospectively analyzed. The optimal cut-off values of NLR, PLR, LMR, and SII were determined by the receiver operating characteristic (ROC) curve. The relationship between different NLR, PLR, LMR and SII levels and the clinic pathological characteristics of the rectal cancer patients were compared. Cox proportional risk model was used for univariate and multivariate regression analysis. Nomogram prediction models of overall survival (OS) and disease-free survival (DFS) of patients with rectal cancer were established by the R Language software. The internal validation and accuracy of the nomograms were determined by the calculation of concordance index (C-index). Calibration curve was used to evaluate nomograms' efficiency. Results: The optimal cut-off values of preoperative NLR, PLR, LMR and SII of OS for rectal cancer patients were 2.44, 134.88, 4.70 and 354.18, respectively. There was statistically significant difference in tumor differentiation degree between the low NLR group and the high NLR group (P<0.05), and there were statistically significant differences in T stage, N stage, TNM stage, tumor differentiation degree and preoperative carcinoembryonic antigen (CEA) level between the low PLR group and the high PLR group (P<0.05). There was statistically significant difference in tumor differentiation degree between the low LMR group and the high LMR group (P<0.05), and there were statistically significant differences in T stage, N stage, TNM stage, tumor differentiation degree and preoperative CEA level between the low SII group and the high SII group (P<0.05). The multivariate Cox regression analysis showed that the age (HR=2.221, 95%CI: 1.526-3.231), TNM stage (Ⅲ grade: HR=4.425, 95%CI: 1.848-10.596), grade of differentiation (HR=1.630, 95%CI: 1.074-2.474), SII level (HR=2.949, 95%CI: 1.799-4.835), and postoperative chemoradiotherapy (HR=2.123, 95%CI: 1.506-2.992) were independent risk factors for the OS of patients with rectal cancer. The age (HR=2.107, 95%CI: 1.535-2.893), TNM stage (Ⅲ grade, HR=2.850, 95%CI: 1.430-5.680), grade of differentiation (HR=1.681, 95%CI: 1.150-2.457), SII level (HR=2.309, 95%CI: 1.546-3.447), and postoperative chemoradiotherapy (HR=1.837, 95%CI: 1.369-2.464) were independent risk factors of the DFS of patients with rectal cancer. According to the OS and DFS nomograms predict models of rectal cancer patients established by multivariate COX regression analysis, the C-index were 0.786 and 0.746, respectively. The calibration curve of the nomograms showed high consistence of predict and actual curves. Conclusions: Preoperative NLR, PLR, LMR and SII levels are all correlated with the prognosis of rectal cancer patients, and the SII level is an independent prognostic risk factor for patients with rectal cancer. Preoperative SII level can complement with the age, TNM stage, differentiation degree and postoperative adjuvant chemoradiotherapy to accurately predict the prognosis of rectal cancer patients, which can provide reference and help for clinical decision.

Appraisal of International Guidelines for Cutaneous Melanoma Management using the AGREE II assessment tool

BACKGROUND

The evidence base behind new melanoma treatments is rapidly accumulating. This is not necessarily reflected in current guidance. A recent UK-based expert consensus statement, published in JPRAS, has called for updates to the widely accepted 2015 National Institute for Health and Care Excellence (NICE) guideline for melanoma (NG14). We aimed to compare the quality of NG14 to all other melanoma guidelines published since.

METHODS

We conducted a systematic search of PubMed, Medline, and online clinical practice guideline databases to identify melanoma guidelines published between 29th July 2015 and 23rd August 2021 providing recommendations for adjuvant treatment, radiotherapy, surgical management, or follow-up care. Three authors independently assessed the quality of identified guidelines using the Appraisal of Guidelines for Research & Evaluation Instrument II (AGREE II) assessment tool, which measures six domains of guideline development. Inter-rater reliability was assessed by Kendall's coefficient of concordance (W).

RESULTS

Twenty-nine guidelines were included and appraised with excellent concordance (Kendall's W for overall guideline score 0.88, p<0.001). Overall, melanoma guidelines scored highly in the domains of 'Scope and purpose' and 'Clarity of presentation', but poorly in the 'Applicability' domain. The NICE guideline on melanoma (NG14) achieved the best overall scores.

CONCLUSION

Melanoma treatment has advanced since NG14 was published, however, the NICE melanoma guideline is of higher quality than more recent alternatives. The planned update of NG14 in 2022 is in demand.

Clustering analysis based on automated electrocardiographic measurements to identify prognostically distinct phenotypes in patients hospitalized for heart failure: a retrospective cohort study

Funding Acknowledgements

Type of funding sources: None.

Background

Heart failure (HF) is a heterogeneous disease with complex structural and electrophysiological derangements of the heart. Attempts to classify HF from the electrophysiological perspective are lacking.

Purpose

To use electrocardiographic (ECG) data for phenotypic classification of patients with HF.

Methods

In this retrospective cohort study, all adult patients hospitalized for HF during 2010-2016 at a tertiary center were included. Automated measurements of the first ECG obtained during the index admission were recorded. K-means clustering using premorbid conditions and selected ECG measurements were used to classify the cohort into four mutually exclusive clusters. The primary (all-cause and cardiovascular mortality) and secondary (ventricular arrhythmia (VA)) outcomes were compared between clusters using Cox regression analysis.

Results

In total, 2849 patients (1363 males, age 75.1 ± 13.4 years) were included. Over a mean follow-up period of 5.37 ± 4.10 years, all-cause and cardiovascular mortality occurred in 2071 (72.7%) and 600 (21.1%) patients respectively, while VA occurred in 110 patients (3.9%). Cluster 1 was characterised by a low heart rate and low ventricular activation time (VAT). Cluster 2 was characterised by old age, low absolute QRS area, and high QTc and QT dispersion. Cluster 3 was characterised by young age, and left ventricular hypertrophy (LVH), and few had history of VA. Cluster 4 was characterised by wide QRS, hypertension, ischaemic heart disease, high VAT, and high absolute T wave area. Cluster 4 had the highest and cluster 1 the lowest risks of all-cause (hazard ratio (HR) 2.96 [1.09, 1.50], p = 0.003; Figure A) and cardiovascular mortality (HR 2.90 [1.15, 2.11], p = 0.004; Figure B). Meanwhile, cluster 2 had the highest risk of VA (HR 2.23 [1.09, 3.85], p = 0.025; Figure C) while clusters 1 and 3 similarly had the lowest risks.

Conclusion

HF presents with clinically and electrophysiologically distinct phenotypes. Clustering analysis is useful in identifying HF phenotypes which are prognostically significant. Abstract Figures A, B, and C

Molecular Characterization of the Viral Structural Genes of Human Rhinovirus A11 from Children Hospitalized with Lower Respiratory Tract Infection in Kunming

BACKGROUND

Human rhinovirus (HRV) is a picornavirus that can cause a variety of respiratory diseases, including the aggravation of chronic respiratory diseases, such as bronchitis, pneumonia, and asthma. Although an increasing number of lower respiratory tract infection cases have been reported with HRV infection in Europe, few such cases have been reported in China.

METHODS

The complete genomic sequences of HRV-A11 epidemic strains were amplifed and obtained by segmented PCR and sequence, then phylogenetic, nucleotide mutation, recombinant, and comparative analyses of amino acid mutations were performed.

RESULTS

Phylogenetic analyses showed that the epidemic strains from three rare cases of pneumonia belong to the HRV-A11 subgenotypes. All strains were highly similar to strains from the USA. No obvious homologous recombination signals were observed in epidemic strains. There were 498 nucleotide and 47 amino acid mutations compared to the HRV-A11 prototype strain. Amino acid mutations were observed at the capsid protein region, P1a, RVA_2147-2155, and RVA_97-114 epitopes of these clinical strains.

CONCLUSIONS

We reported the first case of HRV-A11-associated lower respiratory tract infection in China. These mutations in the P1a, HRV A-specific CD8, and CD4 T-cell epitopes might provide a reference for virological surveillance and vaccine development.

[Effect of moxibustion on renal function and hypercoagulable state in patients with idiopathic membranous nephropathy of low to medium risk with spleen-kidney deficiency and blood stasis]

OBJECTIVE

To compare the effect of moxibustion combined with basic treatment and simple basic treatment on the clinical symptoms, renal function and hypercoagulable state in patients with idiopathic membranous nephropathy (IMN) of low to medium risk with spleen-kidney deficiency and blood stasis.

METHODS

A total of 60 patients with IMN of low to medium risk with spleen-kidney deficiency and blood stasis were randomized into an observation group (30 cases, 2 cases dropped off) and a control group (30 cases, 1 case dropped off). In the control group, the conventional basic treatment of anti-hypertension, regulating blood lipid and anti-coagulation was adopted. On the basis of the control group, moxibustion was applied at Shenshu (BL 23), Pishu (BL 20), Guanyuan (CV 4), Zusanli (ST 36) and Sanyinjiao (SP 6) in the observation group, once a day, 5 days a week continuously with 2 day interval. The treatment of 6 months was required in the both groups. Before treatment and 3 and 6 months into treatment, the total TCM syndrome score, the renal function indexes (24-hour urinary protein quantity [UTP], albumin [ALB], urea nitrogen [BUN] and creatinine [Scr]), the blood coagulation indexes (fibrinogen [FIB], D-Dimer [D-D], p-selection and von Willebrand factor [vWF]), total cholesterol (TC) and triacylglycerol (TG) levels were observed, and the therapeutic efficacy was evaluated on 3 and 6 months into treatment in the two groups.

RESULTS

The effective rates of 3 and 6 months into treatment were 78.6% (22/28) and 89.3% (25/28) in the observation group, which were higher than 62.1% (18/29) and 75.9% (22/29) in the control group respectively (P<0.05). On 3 and 6 months into treatment, the total TCM syndrome scores were decreased compared before treatment in the both groups (P<0.05), and those in the observation group were lower than the control group (P<0.05). On 3 months into treatment, the levels of UTP, FIB, D-D, P-selection and vWF were decreased (P<0.05), the level of ALB was increased (P<0.05) compared before treatment in the observation group; the levels of UTP and FIB were decreased compared before treatment in the control group (P<0.05); the level of ALB in the observation group was higher than that in the control group (P<0.05), the levels of FIB and vWF in the observation group were lower than those in the control group (P<0.05). On 6 months into treatment, the levels of UTP, FIB, D-D, P-selection, vWF, TC and TG were decreased (P<0.05), the levels of ALB were increased (P<0.05) compared before treatment in the both groups (P<0.05); the levels of UTP, FIB, D-D, P-selection, vWF, TC and TG in the observation group were lower than those in the control group, the level of ALB in the observation group was higher than that in the control group (P<0.05).

CONCLUSION

Moxibustion combined with basic treatment can effectively improve the clinical symptoms, renal function and renal microcirculation in patients with idiopathic membranous nephropathy of low to medium risk with spleen-kidney deficiency and blood stasis, the therapeutic effect is superior to the simple basic treatment.

Metabolic engineering of Escherichia coli for efficient osmotic stress-free production of compatible solute hydroxyectoine

Compatible solutes are key for the ability of halophilic bacteria to resist high osmotic stress. They have received wide attention from researchers for their excellent osmotic protection properties. Hydroxyectoine is a particularly important compatible solute, but its production by microbes faces several challenges, including low titer/yield, the presence of the byproduct ectoine, and the requirement of high salinity. Here, we aimed to metabolically engineer Escherichia coli to efficiently produce hydroxyectoine in the absence of osmotic stress without accumulating the byproduct ectoine. First, combinatorial optimization of the expression strength of key genes in the ectoine synthesis module and hydroxyectoine synthesis module was conducted. After optimization of the expression of these genes, 12.12 g/L hydroxyectoine and 0.24 g/L ectoine were obtained at 36 h in shake-flask fermentation with the addition of the co-substrate α-ketoglutarate. Further optimization of the addition of α-ketoglutarate achieved the sole production of hydroxyectoine (i.e., no ectoine accumulation), indicating that the supply of α-ketoglutarate is critically important for sole hydroxyectoine production. Finally, quorum sensing-based auto-regulation of intracellular α-ketoglutarate pool was implemented as an alternative to α-ketoglutarate addition by coupling the expression of sucA with the esaI/esaR circuit, which led to 14.93 g/L hydroxyectoine with a unit cell yield of 1.678 g/g and no ectoine accumulation in the absence of osmotic stress. This is the highest reported titer of sole hydroxyectoine production under salinity-free fermentation to date.

Rapid implementation of triaging system for assessment of breast referrals from primary care centres during the COVID-19 pandemic

OBJECTIVE

The aim of this study was to establish a triaging system for assessment of breast referrals from primary care to ensure safe and effective breast services without compromising breast cancer management.

BACKGROUND

COVID-19 was officially declared a global pandemic on 11 March 2020, and with no effective treatment available, preventing spread has been paramount. Previously, all referrals from primary care were seen in the rapid-access breast clinic (RABC). Clinic appointments exposed patients and healthcare professionals to risk.

METHOD

Initial triage during the lockdown was in line with national governing body guidance, rejected low risk referrals and streamed remaining patients through a telephone consultation to RABC or discharge. A modified triage pathway streamed all patients through virtual triage to RABC, telephone clinic or discharge with advice and guidance categories. Demographics, reasons for referral and outcomes data were collected and presented as median with range and frequency with percentages.

RESULTS

Initial triage (23 March-23 April 2020) found fewer referrals with a higher percentage of breast cancer diagnoses. Modified triage (22 June-17 July 2020) resulted in a 35.1% (99/282) reduction in RABC attendance. Overall cancer detection rate remained similar at 4.2% of all referrals pre-COVID (18/429) and 4.3% (12/282) during modified triage. After six months follow-up of patients not seen in RABC during the modified triage pathway, 18 patients were re-referred to RABC and none were diagnosed with cancer.

CONCLUSION

A modified triage pathway has the potential to improve triage efficiency and prevent unnecessary visits during the COVID-19 pandemic. Further refinement of pathway is feasible in collaboration with primary care.

O-183 Increased Risk Of Hypertensive Disorders Of Pregnancy In Hormone Replacement Therapy Cycle - A Multicenter Cohort Study In Frozen Blastocyst Transfer In Ovulatory Women

Study question

Is hormone replacement therapy cycle (HRT) associated with a higher risk of adverse perinatal outcomes than natural cycle (NC) during frozen embryo transfer (FET)?

Summary answer

Higher rates of hypertensive disorders of pregnancy (HDPs) and macrosomia were detected in HRT-FET as compared to NC-FET in ovulatory women. 

What is known already

Live-birth rates after HRT-FET and NC-FET are found to be comparable. Recent data showed that pregnancies following HRT-FET are associated with higher risks of HDPs. However, the results might be influenced by selection bias as patients with ovulation disorder were more prone to receive HRT than ovulatory women. As is known, patients with ovulation disorder might have more endocrine disturbances than ovulatory women, which could be associated with adverse obstetrical outcomes.

Study design, size, duration

Four large reproductive medical centers in Guangdong province, Southeast of China, took part in this multicenter retrospective cohort study. Patients with regular cycles (25-35 days), who underwent either HRT or NC blastocyst FET and delivered after 20 weeks of gestation between January 2017 and December 2019 were analyzed. Preimplantation genetic testing (PGT) cycles, multiple pregnancies and cases with type II diabetes or preconceptional hypertension were excluded. Each patient only contributed one cycle per cohort.

Participants/materials, setting, methods

Treatment cycles from each patient were linked to their obstetrical medication record and a comprehensive chart review was done to investigate their perinatal outcomes. Maternal and neonatal outcomes were compared between NC-FET and HRT-FET cycles. Multiple logistic regression analyses were performed to adjust the confounding factors including baseline demographics (maternal age, BMI, education level, parity, type of infertility and cause of infertility), as well as IVF characteristics (insemination method and embryo cryopreservation duration).

Main results and the role of chance

A total of 406 cases from NC-FET and 602 cases from HRT-FET were included. A multiple logistic regression analysis showed that pregnancies after HRT-FET had increased odds of HDPs [adjusted odds ratio (aOR) 2.44, 95% confidence interval (CI), 1.39–4.29] in comparison to pregnancies after NC-FET. Singletons born after HRT-FET were at increased risk of macrosomia compared to NC group (aOR 2.74, 95%CI 1.10–6.87). No significant difference could be seen regarding other obstetrical complications including gestational diabetes, placenta previa, placental abruption and postpartum hemorrhage between HRT-FET and NC-FET. No significant differences were noticed for preterm birth and low birthweight between the different endometrial protocols.

Limitations, reasons for caution

Our study was retrospective in nature, and some cases were excluded due to missing data.

Wider implications of the findings

Pregnancies following HRT-FET are associated with higher risks of HDPs and macrosomia in ovulatory women. Physicians should be cautious on the decision of the endometrium preparation for FET, especially for those who can ovulate normally.

Trial registration number

2018YFC100310

[Comparison of different evaluation systems for assessing disease severity and treatment efficacy in patients with chronic obstructive pulmonary disease]

OBJECTIVE

To compare the practicability and clinical value of different evaluation systems for assessing disease severity and treatment efficacy in patients with chronic obstructive pulmonary disease (COPD).

METHODS

We retrospectively analyzed the clinical data of 28 patients with acute exacerbation of COPD admitted to our hospital between November, 2020 and January, 2021. All the patients were assessed with percentage of predicted forced expiratory volume in 1 second (FEV1% pred), COPD assessment test (CAT), modified British Medical Research Council (mMRC), baseline dyspnea index (BDI), clinical COPD questionnaire (CCQ), St. George's respiratory questionnaire (SGRQ), BODE index, Hamilton Depression Rating Scale (HDRS) at admission and with CAT, mMRC, transition dyspnea index (TDI), CCQ, SGRQ, and HDRS at 1 month after discharge. The correlations among FEV1% pred, CAT, mMRC, BDI, CCQ, SGRQ, BODE and HDRS at admission were analyzed. We also compared the TDI and scores of CAT, mMRC, CCQ, SGRQ, and HDRS at 1 month after discharge among the patients using single (n=8), dual (n=10) or triple inhaled medications (n=10) after discharge.

RESULTS

Among these patients, FEV1% pred was moderately correlated with SGRQ and BDI (r=-0.66, r=0.61; P < 0.01), and CCQ activity score was closely correlated with mMRC, SGRQ activity score and BDI (r=0.82, r=0.92, r=-0.89; P < 0.01). SGRQ activity score was closely correlated with mMRC and BDI (r=0.84, r=-0.91; P < 0.01), and SGRQ symptom score was closely correlated with BODE (r=0.80, P < 0.01). SGRQ impact score was moderately correlated with HDRS (r=0.57, P < 0.01). In all the 28 patients, all the evaluation scores except for CCQ mental score and HDRS improved significantly after treatment (P < 0.05). At 1 month after discharge, CCQ total score decreased significantly in single therapy group (P < 0.05); CAT, mMRC, CCQ and SGRQ improved obviously in dual therapy group (P < 0.05); CCQ and SGRQ scores decreased significantly in triple therapy group (P < 0.05); the TDI did not differ significantly among the 3 groups (P>0.05).

CONCLUSION

For patients with COPD, BDI and TDI are recommended over mMRC for assessing dyspnea. CAT, CCQ and SGRQ allow sensitive assessment of the treatment efficacy to serve as routine evaluation tests, and among them SGRQ is the most comprehensive and is thus recommended when sufficient time is allowed. BODE is relatively complex but highly valuable for predicting the patients'survival outcomes. HDRS is recommended for routine screening of depression in patients with COPD.

534 ADVANCED COMMUNICATION SKILLS: TEACHING DURING A PANDEMIC

Introduction

In the first wave of the COVID-19 pandemic, it was recognised there would be an increased demand on clinicians to provide patients and relatives with bad news. The national ban on hospital visiting rapidly changed the way in which this news would be delivered. In recognition of these new challenges, our team sought to design a teaching course that could be implemented quickly and cost effectively, with the aim of improving clinician’s confidence around these difficult skills.

Methods

A teaching programme was created using senior geriatric and palliative care clinicians as simulated patients, open to any grade and speciality. Learners were required to break bad news (BBN) without any visual feedback, to simulate skills required when using the telephone. Surveys were collected to determine self–assessed confidence across four domains (Table 1) before, immediately after and 4–20 weeks after the course. Participants were asked to rank their confidence for each skill on a 5 point scale with 1 being very unsure and 5 being very confident.

Results

Pre-teaching scores showed an average of 3 (neither confident nor unsure) across all domains. After the course all domains improved, most notably around discussing end of life (EoL) care and discussing information over the phone.

Conclusion

This project has highlighted a lack of confidence across all skill levels when it comes to BBN. This confidence is easily improved by a short, cost-effective teaching course. It remains to be seen if this improved confidence translates to better communication with relatives.

[Advances and prospects in metabolic engineering for the production of amino acids]

Fermentative production of amino acids is one of the pillars of the fermentation industry in China. Recently, with the fast development of metabolic engineering and synthetic biology technologies, the metabolic engineering for production of amino acids has been flourishing. Conventional forward metabolic engineering, reversed metabolic engineering based on omics data and in silico simulation, and evolutionary metabolic engineering mimicking the natural evolution, have shown increasingly promising applications. A series of highly efficient and robust amino acids-producing strains have been developed and applied in the industrial production of amino acids. The increasingly fierce market competition has put forward new requirements for strain breeding and selection, such as developing high value-added amino acids, dynamic regulation of cellular metabolism, and adapting to the requirements of new process. This review summarizes the advances and prospects in metabolic engineering for the production of amino acids.

Highly Efficient Production of N-Acetyl-glucosamine in Escherichia coli by Appropriate Catabolic Division of Labor in the Utilization of Mixed Glycerol/Glucose Carbon Sources

Currently, microbial production is becoming a competitive method for N-acetyl-glucosamine production. As the biosynthesis of N-acetyl-glucosamine originating from fructose-6-P directly competes with central carbon metabolism for precursor supply, the consumption of glucose for cell growth and cellular metabolism severely limits the yield of N-acetyl-glucosamine. In this study, appropriate catabolic division of labor in the utilization of mixed carbon sources was achieved by deleting the pfkA gene and enhancing the utilization of glycerol by introducing the glpK mutant. Glycerol thus mainly contributed to cell growth and cellular metabolism, and more glucose was saved for efficient N-acetyl-glucosamine synthesis. By optimizing the ratio of glycerol to glucose, the balancing of cell growth/cellular metabolism and N-acetyl-glucosamine synthesis was achieved. The resulting strain GLALD-7 produced 179.7 g/L N-acetyl-glucosamine using mixed glycerol/glucose (1:8, m/m) carbon sources in a 5 L bioreactor, with a yield of 0.458 g/g total carbon sources (0.529 g/g glucose) and a productivity of 2.57 g/L/h. Coherent high titer/yield/productivity was obtained, with the highest values ever reported, suggesting that an appropriate catabolic division of labor using mixed glycerol/glucose carbon sources is a useful strategy for facilitating the microbial production of chemicals originating from glucose or metabolites upstream of glycolysis.

Detection and recognition of ultrasound breast nodules based on semi-supervised deep learning: a powerful alternative strategy

BACKGROUND

The successful recognition of benign and malignant breast nodules using ultrasound images is based mainly on supervised learning that requires a large number of labeled images. However, because high-quality labeling is expensive and time-consuming, we hypothesized that semi-supervised learning could provide a low-cost and powerful alternative approach. This study aimed to develop an accurate semi-supervised recognition method and compared its performance with supervised methods and sonographers.

METHODS

The faster region-based convolutional neural network was used for nodule detection from ultrasound images. A semi-supervised classifier based on the mean teacher model was proposed to recognize benign and malignant nodule images. The general performance of the proposed method on two datasets (8,966 nodules) was reported.

RESULTS

The detection accuracy was 0.88±0.03 and 0.86±0.02, respectively, on two testing sets (1,350 and 2,220 nodules). When 800 labeled training nodules were available, the proposed semi-supervised model plus 4,396 unlabeled nodules performed better than the supervised learning model (area under the curve (AUC): 0.934±0.026 vs. 0.83±0.050; 0.916±0.022 vs. 0.815±0.049). The performance of the semi-supervised model trained on 800 labeled and 4,396 unlabeled nodules was close to that of the supervised learning model trained on a massive number of labeled nodules (n=5,196) (AUC: 0.934±0.026 vs. 0.952±0.027; 0.916±0.022 vs. 0.918±0.017). Moreover, the semi-supervised model was better than the average accuracy of five human sonographers (AUC: 0.922 vs. 0.889).

CONCLUSIONS

The semi-supervised model can achieve excellent performance for nodule recognition and be useful for medical sciences. The method reduced the number of labeled images required for training, thus significantly alleviating the difficulty in data preparation of medical artificial intelligence.

POS0006 NX-5948, A SELECTIVE DEGRADER OF BTK, SIGNIFICANTLY REDUCES INFLAMMATION IN A MODEL OF AUTOIMMUNE DISEASE

Background:

Aberrant activation of B cells and autoantibody mediated tissue damage are hallmarks of autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Therefore, novel treatments that prevent autoantibody generation or antibody-mediated end organ tissue damage are of high interest. Bruton’s tyrosine kinase (BTK) transduces signals downstream of the B cell receptor (BCR), toll-like receptors, and Fc receptors in B cells and myeloid cells [1]. Overexpression of BTK in B cells leads to hyperactive BCR signaling, plasma cell generation, autoantibody secretion, and an SLE-like disease in mice [2]. Conversely, reducing BTK expression in B cells can ameliorate disease in Lyn-deficient mice.[3] BTK inhibitors, such as evobrutinib, have entered clinical studies for the treatment of autoimmune diseases.[4]

Objectives:

Small molecule-induced protein degradation offers a unique approach to target BTK; this approach simultaneously eliminates both BTK kinase activity and BTK-mediated scaffolding interactions in the signalosome. Chimeric Targeting Molecules (CTMs) are small molecules that catalyze ubiquitylation and proteasomal degradation of target proteins and are comprised of a ubiquitin ligase binding element (“harness”), a linker, and a target binding element (“hook”). NX-5948 is a CTM that contains a BTK hook linked to a cereblon (CRBN) harness. We examined the activity of NX-5948 in a collagen-induced arthritis model as part of an assessment of its potential as a drug candidate for autoimmune disease.

Methods:

Cellular degradation of BTK, Aiolos and Ikaros as well as induction of CD69 and CD86 was determined using flow cytometry. Degradation of BTK in CD-1 mice or cynomolgus monkey was determined using flow cytometry analysis. In a collagen-induced arthritis (CIA) model, mice were vaccinated with type II collagen and treated before the onset of symptoms. Serum cytokine and anti-type II collagen antibody levels were determined using Luminex and ELISA, respectively.

Results:

In human PBMCs, NX-5948 degrades BTK at sub-nanomolar concentrations and inhibits BCR signaling as measured by CD69 and CD86 induction in anti-IgM-stimulated B cells with similar potency. Oral administration of NX-5948 in mice leads to BTK degradation to <10% of baseline levels in circulating and splenic B cells. NX-5948 also promotes potent BTK degradation in cynomolgus monkeys, and it can suppress BTK levels to <10% of baseline levels after a single oral dose as low as 10 mg/kg.

Unlike IMiD drugs such as lenalidomide, the CRBN harness of NX-5948 was designed to avoid the degradation of known CRBN neo-substrates Aiolos (IKZF3) and Ikaros (IKZF1). In primary human T cells, NX-5948 induces minimal degradation of Aiolos and Ikaros and does not promote IL-2 secretion suggesting that NX-5948 does not convey IMiD activity associated with agents such as lenalidomide.

We examined the activity of NX-5948 in a mouse CIA model compared to that of the BTK inhibitor ibrutinib or dexamethasone as a positive control. In mice treated with NX-5948, symptoms of arthritis were resolved, and a significant reduction in arthritis clinical score was observed. Treatment with NX-5948 resulted in a reduction in anti-type II collagen titer and serum levels of the pro-inflammatory cytokine IL-6. Treatment with NX-5948 yielded superior anti-inflammatory activity relative to ibrutinib and similar activity to dexamethasone. Treatment with NX-5948 was well-tolerated and, unlike dexamethasone, did not promote body weight loss.

Conclusion:

Degradation of BTK by NX-5948 shows robust activity in a CIA model compared to existing agents tested as controls. These findings provide support for further investigation of NX-5948 in additional models of autoimmune disease to inform plans for clinical development.

References:

[1]Crofford et al. 2016. Expert Rev Clin Immunol 12: 763–773.

[2]Kil et al. 2012. Blood 119: 3744-3756.

[3]Whyburn et al. 2003. J Immunol 171: 1850-1858.

[4]Haselmayer, et. Al. 2019. J Immunol 202: 2888-2906.

Disclosure of Interests:

DANIEL ROBBINS Shareholder of: Nurix therapeutics, Employee of: Nurix therapeutics, Mark Noviski Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, May Tan Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Cristiana Guiducci Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Timothy Ingallinera Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Dane Karr Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Aileen Kelly Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Zef Konst Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Austin Tenn-McClellan Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Jenny McKinnell Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Luz Perez Employee of: Nurix Therapeutics, Gwenn Hansen Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics, Ryan Rountree Shareholder of: Nurix Therapeutics, Employee of: Nurix Therapeutics

646 Appraisal of International Guidelines for Malignant Melanoma Management Using the AGREE II Assessment Tool

Background

Recently, the widely accepted NICE guidelines for melanoma management have been challenged by a UK-based expert consensus statement. A review of alternative clinical practice guidelines (CPGs) could guide future CPG updates and developments. The AGREE II tool assesses CPGs across six domains: ‘Scope and purpose’, ‘Stakeholder involvement’, ‘Rigour of development’, ‘Clarity of presentation’, ‘Applicability’, and ‘Editorial independence’.

Method

We conducted a systematic search of Pubmed, Medline and online CPG databases to identify melanoma CPGs published between January 2014 and March 2020 providing recommendations for: adjuvant treatment, radiotherapy, surgical management, or follow-up care. Three authors independently assessed the quality of identified CPGs using the AGREE II assessment tool. Inter-rater reliability was assessed by Kendall’s coefficient of concordance (W).

Results

Twenty-nine CPGs were included and appraised with excellent reliability (Kendall’s W for overall GPC score 0.85, p &lt; 0.001). Overall, melanoma CPGs scored highly in the scope and purpose and clarity of presentation domains, and poorly in the applicability domain. The NICE guideline achieved the best overall scores.

Conclusions

The NICE melanoma CPGs are higher quality than alternatives but should be updated to reflect recent landmark trials. The AGREE II tool is currently limited by its incapacity to compare guidelines to latest evidence.

Surgical and non-surgical approaches in the management of lower limb post-thrombotic syndrome

Introduction: Post-thrombotic syndrome (PTS) is a common lifelong condition affecting up to 50% of those suffering from deep vein thrombosis (DVT). PTS compromises function and quality of life with subsequent venous ulceration in up to 29% of those affected.Areas covered: A literature review of surgical and non-surgical approaches in the prevention and treatment of PTS was undertaken. Notable areas include the use of percutaneous endovenous interventions and the use of graduated compression stockings (GCS) after acute proximal DVT.Expert opinion: In patients with acute iliofemoral DVT, we think it is important to have a frank conversation with the patient about catheter-directed thrombolysis, aiming to reduce the severity of PTS experienced. We advocate ultrasound-accelerated thrombolysis with adjunctive procedures, such as deep venous stenting for proximal iliofemoral DVT. For patients with isolated femoral DVT, we believe that anticoagulation and GCS should be recommended. In patients with established PTS, we recommend GCS for symptomatic relief. We recommend that patients engage in regular exercise where possible with the prospect of gaining symptomatic relief. For those with severe PTS that has a significant effect on quality of life, we discuss the patient's case at a multi-disciplinary team meeting to plan for endovenous intervention.

The efficacy and safety of high-dose tranexamic acid in adolescent idiopathic scoliosis: a meta-analysis

Background

This study aimed to evaluate the efficacy and safety of using high-dose intravenous tranexamic acid (TXA) to reduce blood loss in idiopathic scoliosis surgery.

Methods

This study was a meta-analysis, which consisted of retrospective cohort studies (RCSs) and randomized control trials (RCTs) found by searching electronic databases, namely PubMed, Web of Science, The Cochrane Central Register of Controlled Trials (CENTRAL), and the Google Scholar Database, dating from 1960 to 2019. The points of interest included total blood loss, a need for transfusion and transfusion criteria, surgery time, and the evidence of intraoperative and postoperative complications, such as seizures or thromboembolic events. The weighted mean differences (WMD) and 95% confidence interval (CI) of blood loss in the TXA intervention group compared to the control or placebo group were extracted and combined using the random effects model.

Results

In this meta-analysis, there was a total of three RCSs and two RCTs, which involved 334 patients. The results showed that blood loss is significantly reduced, with a weighted mean difference in the TXA group (WMD = − 525.14, P = 0.0000, CI ranged from − 839.83, − 210.44, I² = 82%). Heterogeneity was assessed using the random effects model.

Conclusions

A high dose of intravenous TXA reduced blood loss during adolescent idiopathic scoliosis surgery and did not lead to any significant thromboembolic event. Therefore, a high dose appears to be effective and safe for adolescent idiopathic scoliosis surgery. However, more high-quality research based on larger randomized controlled trials is still needed.

Use of an electronic medical record dashboard to identify gaps in osteoporosis care

Using an electronic medical record (EMR)-based dashboard, this study explored osteoporosis care gaps in primary care. Eighty-four physicians shared their practice activities related to bone mineral density testing, 10-year fracture risk calculation and treatment for those at high risk. Significant gaps in fracture risk calculation and osteoporosis management were identified.

PURPOSE

To identify care gaps in osteoporosis management focusing on Canadian clinical practice guidelines (CPG) related to bone mineral density (BMD) testing, 10-year fracture risk calculation and treatment for those at high risk.

METHODS

The ADVANTAGE OP EMR tool consists of an interactive algorithm to facilitate assessment and management of fracture risk using CPG. The FRAX® and Canadian Association of Radiologists and Osteoporosis Canada (CAROC) tools were embedded to facilitate 10-year fracture risk calculation. Physicians managed patients as clinically indicated but with EMR reminders of guideline recommendations; participants shared practice level data on management activities after 18-month use of the tool.

RESULTS

Eighty-four physicians (54%) of 154 who agreed to participate in this study shared their aggregate practice activities. Across all practices, there were 171,310 adult patients, 40 years of age and older, of whom 17,214 (10%) were at elevated risk for fracture. Sixty-two percent of patients potentially at elevated risk for fractures did not have BMD testing completed; most common reasons for this were intention to order BMD later (48%), physician belief that BMD was not required (15%) and patient refusal (20%). For patients with BMD completed, fracture risk was calculated in 29%; 19% were at high risk, of whom 37% were not treated with osteoporosis medications as recommended by CPG.

CONCLUSION

Despite access to CPG and fracture risk calculators through the ADVANTAGE OP EMR tool, significant gaps remain in fracture risk calculation and osteoporosis management. Additional strategies are needed to address this clinical inertia among family physicians.

Letter to the Editor: Effects of the COVID-19 Pandemic on COVID-19 Negative Geriatric Patients with Hip Fractures

Since December 2019, the novel coronavirus (COVID-19) had affected millions globally, particularly putting elderly and persons with chronic diseases at risk (1). 95% of all COVID-19 deaths in Singapore are older adults (2). As public health policymakers try to control the pandemic by focusing resources on COVID-19, the general population fear contracting coronavirus from hospitals, resulting in changes in their healthcare seeking behaviour. We describe two cases demonstrating the direct and indirect impact of COVID-19 to our geriatric patients in Singapore who have sustained hip fractures.