The feasibility of amide proton transfer imaging at 3 T for bladder cancer: a preliminary study

AIM

To investigate the optimal amide proton transfer (APT) imaging parameters for bladder cancer (BCa), the influence of different protein concentrations and pH values on APT imaging, and to establish the reliability of APT imaging in healthy volunteers and patients with BCa.

MATERIALS AND METHODS

The optimal APT imaging parameters for BCa were experimentally optimised using cross-linked bovine serum albumin (BSA) phantoms. BSA phantoms were scanned with different values for the saturation power, saturation duration and number of excitations. Meanwhile, BSA phantoms containing different protein concentrations and solutions of different pH levels were scanned. The interobserver agreement of the asymmetric magnetisation transfer ratio (MTR_asym) was assessed in 11 healthy volunteers and 18 patients with BCa.

RESULTS

The optimal scanning scheme consisted of 1 excitation, a saturation power of 2 μT, and a saturation time of 2 s. The APT signal intensity increased as the protein concentration increased and as the pH decreased. The MTR_asym showed good concordance for all subjects. The MTR_asym of BCa tissue was significantly higher (1.81 ± 0.71) than that of bladder wall in healthy volunteers (0.34 ± 0.12) and normal bladder wall in patients with BCa (0.31 ± 0.11; p<0.001). There was no significant difference between the bladder wall of healthy volunteers and the normal bladder wall of patients with BCa.

CONCLUSION

APT imaging showed potential value for application in BCa.

[Predictive value of prognostic inflammatory and tumor score in intrahepatic cholangiocarcinoma]

Objective: To compare and analyze the predictive value of different inflammatory factors and tumor markers in intrahepatic cholangiocarcinoma and to develop a new and effective preoperative prognostic scoring system. Methods: 102 and 72 cases with intrahepatic cholangiocarcinoma who underwent radical surgery in Tianjin Medical University Cancer Institute and Hospital and the Affiliated Hospital of Weifang Medical University were selected as the experimental group and the validation group, respectively. Clinicopathological and follow-up data were collected. Cox proportional-hazards model was used to analyze the predictive value of different prognostic markers. The relationship between prognostic markers and clinicopathological data was analyzed by rank sum test, χ² or Fisher's exact test. Results: Among the direct inflammatory factors, tumor markers and combined inflammatory factors, prognostic inflammatory index (PII), carbohydrate antigen (CA) 19-9 and systemic inflammation score (SIS) were the most significant predictive factors for postoperative survival outcomes in patients with intrahepatic cholangiocarcinoma. The prognostic inflammatory and tumor score (PITS) was proposed as a new prognostic scoring system for intrahepatic cholangiocarcinoma. PII and CA19-9 were included into the scoring criteria for prognostic stratification of patients. PITS was an independent predictor of tumor-free survival and overall survival in patients with intrahepatic cholangiocarcinoma. Patients with high-grade PITS had later tumor grade and higher frequency of vascular invasion. Conclusion: PITS is highly effective prognostic scoring system for patients with intrahepatic cholangiocarcinoma. In addition, PITS is recommended for preoperative prognostic stratification in patients with intrahepatic cholangiocarcinoma.

Artificial stem cells mediated inflammation-tropic delivery of antiviral drugs for pneumonia treatment

Background

Cytomegalovirus (CMV) pneumonia is a major cause of morbidity and mortality in immunodeficiency individuals, including transplant recipients and Acquired Immune Deficiency Syndrome patients. Antiviral drugs ganciclovir (GCV) and phosphonoformate (PFA) are first-line agents for pneumonia caused by herpesvirus infection. However, the therapy suffers from various limitations such as low efficiency, drug resistance, toxicity, and lack of specificity.

Methods

The antiviral drugs GCV and PFA were loaded into the pH-responsive nanoparticles fabricated by poly(lactic-co-glycolic acid) (PLGA) and 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and further coated with cell membranes derived from bone marrow mesenchymal stem cells to form artificial stem cells, namely MPDGP. We evaluated the viral suppression effects of MPDGP in vitro and in vivo.

Results

MPDGP showed significant inflammation tropism and efficient suppression of viral replication and virus infection-associated inflammation in the CMV-induced pneumonia model. The synergistic effects of the combination of viral DNA elongation inhibitor GCV and viral DNA polymerase inhibitor PFA on suppressing the inflammation efficiently.

Conclusion

The present study develops a novel therapeutic intervention using artificial stem cells to deliver antiviral drugs at inflammatory sites, which shows great potential for the targeted treatment of pneumonia. To our best knowledge, we are the first to fabricate this kind of artificial stem cell to deliver antiviral drugs for pneumonia treatment.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01547-x.

Increased 5-hydroxymethylcytosine is a favorable prognostic factor of Helicobacter pylori-negative gastric cancer patients

BACKGROUND

Most gastric cancer (GC) patients are diagnosed at middle or late stage because the symptoms in early stage are obscure, which causes higher mortality rates of GC. Helicobacter pylori (H. pylori) was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation. 5-hydroxymethylcytosine (5-hmC) plays complex roles in gene regulation of tumorigenesis and can be considered as an activating epigenetic mark of hydroxymethylation.

AIM

To explore the association between 5-hmC levels and the progression and prognosis of GC patients with or without H. pylori infection.

METHODS

A retrospective cohort study was conducted to estimate the predicted value of 5-hmC level in the progression and prognosis of GC patients with different H. pylori infection status. A total of 144 GC patients were recruited.

RESULTS

The levels of 5-hmC were significantly decreased in tumor tissues (0.076 ± 0.048) compared with the matched control tissues (0.110 ± 0.057, P = 0.001). A high level of 5-hmC was an independent significant favorable predictor of overall survival in GC patients (hazard ratio = 0.61, 95% confidence interval: 0.38-0.98, P = 0.040), the H. pylori-negative GC subgroup (hazard ratio = 0.30, 95% confidence interval: 0.13-0.68, P = 0.004) and the GC patients with TNM stage Ⅰ or Ⅱ (hazard ratio = 0.32, 95% confidence interval: 0.13-0.77, P = 0.011).

CONCLUSION

Increased 5-hmC is a favorable prognostic factor in GC, especially for H. pylori-negative subgroups.

BaseFormer: Transformer based Base-Caller for Fast and Accurate Next Generation Sequencing

Gene sequencing technology is a tool which greatly impacts modern biology and medicine. The next-generation sequencing (NGS) lies at the heart of gene sequencing for its massively increasing throughput, but it is difficult to analyze the large quantities of fluorescent images with high accuracy because the fluorescent signals are weak with varying noise signals, and current designs are limited on accuracy and speed. In this paper, we proposed a novel deep learning based gene sequencing pipeline with semi-automatic labelling method. The obtained results are promising, especially on the high-density data, as the BaseFormer surpasses the traditional methods in terms of cluster quality (Q30: 88 %), throughput (16.5% better), and with similar and low error rate (down to 0.137% on average, best at 0.068 % on high-density data).

A potential EBV-related classifier is associated with the efficacy of immunotherapy in gastric cancer

Background

Gastric cancer (GC) is a global health problem. As a complicated heterogeneous disease, The Cancer Genome Atlas (TCGA) Research Network recognized four subtypes of GC, including Epstein-Barr virus (EBV)-positive GC (EBVaGC), which accounts for approximately 9% of all GC cases. The response to immunotherapy in GC is limited, and whether EBV status is a predictor of immunotherapy remains controversial.

Methods

The differential gene expression analysis was utilized to compare the gene expression between the EBV-positive group and the EBV-negative group in the TCGA-Stomach Adenocarcinoma (TCGA-STAD) cohort. Weighted gene co-expression network analysis (WGCNA), protein-protein interaction (PPI) network analysis, and gene functional enrichment analysis were used to investigate the most pivotal hub genes and their roles. The “Estimation of Stromal and Immune cells in Malignant Tumours using Expression data” (ESTIMATE) and CIBERSORT algorithms were performed to infer the immune compositions of tissue samples. Furthermore, quantitative real-time polymerase chain reaction (RT-qPCR) and survival analysis were used to validate the expression and prognosis of these hub genes in Sun Yat-sen University Cancer Center (SYSUCC) cohort. A GC cohort that received anti-programmed cell death 1 (PD-1) therapy was used to analyze the predicted efficacy based on the expression of hub genes.

Results

There is a total of 1,686 differentially expressed genes (DEGs) between the EBV-positive group and EBV-negative group, and WGCNA identified a yellow-colored module that was most related to EBV features. Functional enrichment analysis of 144 genes in this yellow module demonstrated that these genes primarily performed immune-related functions, and PPI network analysis through the CytoHubba plug-in identified 11 hub genes in the network. The RT-qPCR results in the SYSUCC cohort further validated that the hub genes were all increased in the EBV-positive group. Finally, we found that a potential classifier was associated with the efficacy of immunotherapy based on the expression of these 11 hub genes.

Conclusions

Our study identified several hub genes associated with EBV status that are closely related to the immune microenvironmental features of EBVaGC and may be used as molecular markers for predicting the immune response in GC.

Engineering Polymers via Understanding the Effect of Anchoring Groups for Highly Stable Liquid Metal Nanoparticles

Liquid metal nanoparticles (LMNPs) have recently attracted much attention as soft functional materials for various biorelated applications. Despite the fact that several reports demonstrate highly stable LMNPs in aqueous solutions or organic solvents, it is still challenging to stabilize LMNPs in biological media with complex ionic environments. LMNPs grafted with functional polymers (polymers/LMNPs) have been fabricated for maintaining their colloidal and chemical stability; however, to the best of our knowledge, no related work has been conducted to systematically investigate the effect of anchoring groups on the stability of LMNPs. Herein, various anchoring groups, including phosphonic acids, trithiolcarbonates, thiols, and carboxylic acids, are incorporated into brush polymers via reversible addition-fragmentation chain transfer (RAFT) polymerization to graft LMNPs. Both the colloidal and chemical stability of such polymer/LMNP systems are then investigated in various biological media. Moreover, the influence of multidentate ligands is also investigated by incorporating different numbers of carboxylic or phosphonic acid into the brush polymers. We discover that increasing the number of anchoring groups enhances the colloidal stability of LMNPs, while polymers bearing phosphonic acids provide the optimum chemical stability for LMNPs due to surface passivation. Thus, polymers bearing multidentate phosphonic acids are desirable to decorate LMNPs to meet complex environments for biological studies.

PDE4D binds and interacts with YAP to cooperatively promote HCC progression

The role of cAMP in the development of hepatocellular carcinoma (HCC) is controversial and the biological function of cAMP-hydrolysing enzyme phosphodiesterase 4D (PDE4D) in HCC remains unclear. In this study, we observed markedly higher PDE4D expression in HCC patients with poor survival. PDE4D bound to yes-associated protein (YAP), and PDE4D expression positively correlated with YAP expression in HCC. Overexpression of PDE4D increased YAP dephosphorylation and activity and promoted HCC cell growth in vitro and in vivo, which was attenuated by the YAP inhibitor verteporfin. In contrast, silencing PDE4D reduced YAP expression and HCC cell growth. Notably, forced expression of YAP promoted PDE4D and YAP target gene expression and cell growth, which were abrogated by the PDE4D inhibitor roflumilast. Mechanistically, silencing of YAP caused PDE4D downregulation and HCC cell apoptosis via extracellular signal-regulated kinase (ERK) activation. Roflumilast activated cAMP-PKA signaling and induced cAMP-PKA-dependent YAP phosphorylation at serine 127, resulting in YAP degradation and suppression of HCC growth, which were reversed by the PKA inhibitor PKI. Additionally, transfection of the YAP-S127A mutant reversed roflumilast-mediated suppression of YAP and cell growth. Taken together, our findings indicate that PDE4D binds to and interacts with YAP to promote HCC progression. Targeting the PDE4D-YAP interaction with roflumilast may be an effective strategy for HCC treatment.

Effects of Liuzijue Qigong Posture on Aerodynamics of Phonation in Healthy Volunteers

OBJECTIVES

To verify the possible function of Liuzijue Qigong (LQG), a kind of traditional Chinese health exercise, in improving phonation.

METHODS

A total of 30 healthy volunteers (10 males, 20 females) without voice disorders were included. The subjects were asked to have phonation tasks at the sitting and LQG postures. Aerodynamic, electroglottographic, and acoustic parameters were measured. Expiratory Volume (FVC); Subglottic Pressure at comfortable phonation (SGP), Glottal Resistance (GR), Glottal Efficiency (GE); Contact Quotient (CQ), Mean Flow (MF), Fundamental frequency (F0), Mean Sound Pressure Level (SPL); Phonation Threshold Pressure (PTP); and Maximum Phonation Time (MPT) were measured and analyzed.

RESULTS

In total subjects, the analysis showed a significant increase in FVC (P = 0.020), SGP (P = 0.043), F0 (P = 0.021), and PTP (P = 0.000) at the LQG posture when compared with the sitting posture, and there is no difference in CQ, MF, SPL, GR, GE, and MPT.

CONCLUSIONS

The results showed LQG posture increased the respiratory support and glottal closure, while induced the respiratory system and vocal system in coordination to improve phonation. It is logical to postulate that LQG has potential in the management of voice disorders with glottal closure insufficiency.

Recent Advances in Single Fe-Based Nanoagents for Photothermal-Chemodynamic Cancer Therapy

Monomodal cancer therapies are often unsatisfactory, leading to suboptimal treatment effects that result in either an inability to stop growth and metastasis or prevent relapse. Thus, synergistic strategies that combine different therapeutic modalities to improve performance have become the new research trend. In this regard, the integration of photothermal therapy (PTT) with chemodynamic therapy (CDT), especially PTT/CDT in the second near-infrared (NIR-II) biowindow, has been demonstrated to be a highly efficient and relatively safe concept. With the rapid development of nanotechnology, nanoparticles can be designed from specific elements, such as Fe, that are equipped with both PTT and CDT therapeutic functions. In this review, we provide an update on the recent advances in Fe-based nanoplatforms for combined PTT/CDT. The perspectives on further improvement of the curative efficiency are described, highlighting the important scientific obstacles that require resolution in order to reach greater heights of clinical success. We hope this review will inspire the interest of researchers in developing novel Fe-based nanomedicines for multifunctional theranostics.

Solid-state degradation and visual detection of the nerve agent GB by SA@UiO-66-NH2@PAMAM hydrogel

A new sodium alginate (SA) composite hydrogel for rapid solid-state degradation of organophosphorus derivatives and can be used to monitor hydrolysis of nerve agent GB.

Direct Detection of Pulmonary Fibrosis by Near-Infrared-Responsive Biomimetic Platelets

Background

Purpose

Methods

Results

Conclusion

Overexpression of PDE4D in mouse liver is sufficient to trigger NAFLD and hypertension in a CD36-TGF-β1 pathway: therapeutic role of roflumilast

Emerging evidence has shown that nonalcoholic fatty liver disease (NAFLD) may be both a consequence and a cause of hypertension. Recent studies have demonstrated that phosphodiesterase 4 (PDE4)-cAMP signaling represents a pathway relevant to the pathophysiology of metabolic disorders. This study aims to investigate the impact and the underlying mechanism of PDE4 in the pathogenesis of NAFLD and its associated hypertension. Here we demonstrated that high-fat-diet (HFD) fed mice developed NAFLD and hypertension, with an associated increase in hepatic PDE4D expression, which can be prevented and even reversed by PDE4 inhibitor roflumilast. Furthermore, we demonstrated that hepatic overexpression of PDE4D drove significant hepatic steatosis and elevation of blood pressure. Mechanistically, PDE4D activated fatty acid translocase CD36 signaling which facilitates hepatic lipid deposition, resulting in TGF-β1 production by hepatocytes and excessive TGF-β1 signaling in vessels and consequent hypertension. Specific silencing of TGF-β1 in hepatocytes by siRNA using poly (β-amino ester) nanoparticles significantly normalized hepatic PDE4D overexpression-activated TGF-β1 signaling in vessels and hypertension. Together, the conclusions indicated that PDE4D plays an important role in the pathogenesis of NAFLD and associated hypertension via activation of CD36-TGF-β1 signaling in the liver. PDE4 inhibitor such as roflumilast, which is clinically approved for chronic obstructive pulmonary disease (COPD) treatment, has the potential to be used as a preventive or therapeutic drug against NAFLD and associated hypertension in the future.

Tb3+ luminescence cholate hydrogel-based multi-functionalized platform for Hg2+ and NO2 detection

In this paper, Tb3+ luminescence cholate hydrogel (Tb3+/hydrogel) was selected as a multi-functionalized platform, and PS-BD@Tb3+/hydrogel or PS-BS@Tb3+/hydrogel systems were fabricated respectively for selective detecting of Hg2+ in water and...

Efficient Photoacoustic Imaging With Biomimetic Mesoporous Silica-Based Nanoparticles

Indocyanine green (ICG), a near-infrared (NIR) fluorescent dye approved by the Food and Drug Administration (FDA), has been extensively used as a photoacoustic (PA) probe for PA imaging. However, its practical application is limited by poor photostability in water, rapid body clearance, and non-specificity. Herein, we fabricated a novel biomimetic nanoprobe by coating ICG-loaded mesoporous silica nanoparticles with the cancer cell membrane (namely, CMI) for PA imaging. This probe exhibited good dispersion, large loading efficiency, good biocompatibility, and homologous targeting ability to Hela cells in vitro. Furthermore, the in vivo and ex vivo PA imaging on Hela tumor-bearing nude mice demonstrated that CMI could accumulate in tumor tissue and display a superior PA imaging efficacy compared with free ICG. All these results demonstrated that CMI might be a promising contrast agent for PA imaging of cervical carcinoma.

Mind the gap: independent directors and corporate social responsibility in China

Purpose

This study aims to examine the effect of independent directors on the corporate social responsibility (CSR) gap – a misalignment between internal and external CSR. More specifically, the authors investigate how two types of independent directors (i.e. politically connected and foreign) affect a firm’s CSR gap in China.

Design/methodology/approach

The authors use the fixed-effects regression model to analyze the panel dataset, which is conducted by a sample of Chinese publicly listed firms from 2008 to 2015.

Findings

The findings indicate that, on average, firms undertake more external than internal CSR actions. Importantly, the authors find that firms having politically connected independent directors on boards have a wider gap between their internal and external CSR. In contrast, firms having foreign independent directors on boards have a narrower gap between their internal and external CSR.

Practical implications

This study provides insights into the role of independent directors in increasing or decreasing the gap between a firm’s internal and external CSR actions, which offers important implications for policymakers and investors.

Originality/value

This study extends the literature on the causes of the CSR gap and deepens the theoretical understanding of the governance role of independent directors in China.

Prediction of pandemic risk for animal-origin coronavirus using a deep learning method

Background

Coronaviruses can be isolated from bats, civets, pangolins, birds and other wild animals. As an animal-origin pathogen, coronavirus can cross species barrier and cause pandemic in humans. In this study, a deep learning model for early prediction of pandemic risk was proposed based on the sequences of viral genomes.

Methods

A total of 3257 genomes were downloaded from the Coronavirus Genome Resource Library. We present a deep learning model of cross-species coronavirus infection that combines a bidirectional gated recurrent unit network with a one-dimensional convolution. The genome sequence of animal-origin coronavirus was directly input to extract features and predict pandemic risk. The best performances were explored with the use of pre-trained DNA vector and attention mechanism. The area under the receiver operating characteristic curve (AUROC) and the area under precision-recall curve (AUPR) were used to evaluate the predictive models.

Results

The six specific models achieved good performances for the corresponding virus groups (1 for AUROC and 1 for AUPR). The general model with pre-training vector and attention mechanism provided excellent predictions for all virus groups (1 for AUROC and 1 for AUPR) while those without pre-training vector or attention mechanism had obviously reduction of performance (about 5–25%). Re-training experiments showed that the general model has good capabilities of transfer learning (average for six groups: 0.968 for AUROC and 0.942 for AUPR) and should give reasonable prediction for potential pathogen of next pandemic. The artificial negative data with the replacement of the coding region of the spike protein were also predicted correctly (100% accuracy). With the application of the Python programming language, an easy-to-use tool was created to implements our predictor.

Conclusions

Robust deep learning model with pre-training vector and attention mechanism mastered the features from the whole genomes of animal-origin coronaviruses and could predict the risk of cross-species infection for early warning of next pandemic.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-021-00912-6.

Tb3+-Doped Ag-MOFs for fluorescent detection of formaldehyde in a novel smartphone platform and its removal applications in milk products and wastewater

As one kind of reactive carbonyl species (RCS), formaldehyde (FA) with a high concentration could be extremely toxic to living bodies as well as the environment. This paper reports a three-dimensional (3D) Tb3+@Ag-MOFs-based fluorescent probe for fast sensing of FA, which uses a novel turn-on mechanism based on the luminescence induced by Tb3+. The MOF sensor shows broad dynamic ranges of 0.1-1 mM for FA with the detection limit of 1.9 μM. For online and real-time detection of FA, a portable smartphone platform was employed to analyze the RGB values of the fluorescence by a smartphone application. By incorporating this probe into a polyacrylonitrile (PAN) layer, we synthesized a film composite that could effectively remove FA in real samples including milk and chemical factory wastewater, and the removal rate reached 98.52% and 95.38% respectively. Moreover, the potential of the film to remove gaseous FA was confirmed by experiments as well.

Mastery of type 2 diabetes prevention and treatment knowledge by general practitioners in Shanghai: a cross-sectional study

Background

To study the competency of general practitioners (GPs) in Shanghai, China on prevention and management of type 2 diabetes, also understand factors that may prohibit it.

Methods

A survey questionnaire with 25 questions was designed based on 2013 Chinese Type 2 Diabetes Prevention Guidelines and Chinese Type 2 Diabetes Prevention Guidelines (Grassroots Edition) and conducted among 789 GPs who work at 54 community healthcare centers (CHCs) within 16 districts at Shanghai, China. Excel 2016 and SPSS 24.0 were used for data analysis, and a difference of P < 0.05 was considered to be statistically significant.

Results

The GPs did poorly on three aspect of diabetes prevention and treatment: (1) treatment goals in elderly patients, (2) screening methods for high-risk population, and (3) aspirin contraindications. The statistical analysis data showed that GPs who finished standardized training had correct answer on 13.58 ± 3.31 questions out of total 25, with mean accuracy rate of 54.32%. Except the questions for high-risk population screening method and the diagnostic criteria for type 2 diabetes, there was no difference in the accuracy of other questions between GPs with or without standardized training (P < 0.05). However, sex, educational level, and subspecialty experience are affective factors on their competency in type 2 diabetes prevention and treatment knowledge.

Conclusion

The results indicated that communities should strengthen the training of GPs in diabetes management and bidirectional referral. Frequent continuing education and skills training should be provided among GPs at CHCs to ensure their competency of type 2 diabetes prevention and treatment knowledge after obtaining their GP license disregard of their standardized training. In addition, attention should be paid to GPs who had lower education background or non-clinical subspecialty experience to strengthen their clinical knowledge of type 2 diabetes.

A Novel Biomimetic Nanoprobe as a Photoacoustic Contrast Agent

Specific detection of tumors is of pivotal importance to cancer prevention and therapy yet a big challenge. Photoacoustic imaging (PAI) as an emerging non-invasive modality has shown great potential in biomedical and clinical applications. The performance of PAI largely depends on the light-absorption coefficient of the imaged tissue and the PAI contrast agent being used, either endogenously or exogenously. The exogenous contrast agents developed so far have greatly helped to improve PAI, but still have some limitations, such as lack of targeting capacity and easy clearance by the host immune system. Herein, we fabricated a biomimetic nanoprobe with cell membrane coating as a novel PAI contrast agent, namely, MPD [membrane-coated poly(lactic-co-glycolic acid) (PLGA)/dye]. In brief, the organic dye 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindotricarbocyanine iodide (DiR) was encapsulated by the Food and Drug Administration–approved polymer, poly(lactic-co-glycolic acid) (PLGA), to form polymer nanoparticles by emulsification. The nanoparticles are further coated with the cancer cell membrane to form MPD. MPD has outstanding biocompatibility, tumor specificity, and in vivo stability. Thus, MPD is a versatile NIR-I theranostic nanoplatform for PAI-guided cancer diagnosis and therapy.