Single-cell EpiChem jointly measures drug-chromatin binding and multimodal epigenome.

Studies of molecular and cellular functions of small-molecule inhibitors in cancer treatment, eliciting effects by targeting genome and epigenome associated proteins, requires measurement of drug-target engagement in single-cell resolution. Here we present EpiChem for in situ single-cell joint mapping of small molecules and multimodal epigenomic landscape. We demonstrate single-cell co-assays of three small molecules together with histone modifications, chromatin accessibility or target proteins in human colorectal cancer (CRC) organoids. Integrated multimodal analysis reveals diverse drug interactions in the context of chromatin states within heterogeneous CRC organoids. We further reveal drug genomic binding dynamics and adaptive epigenome across cell types after small-molecule drug treatment in CRC organoids. This method provides a unique tool to exploit the mechanisms of cell type-specific drug actions.

RESISTANCE TO PHYTOPHTHORA1 promotes cytochrome b559 formation during early photosystem II biogenesis in Arabidopsis.

As an essential intrinsic component of photosystem II (PSII) in all oxygenic photosynthetic organisms, heme-bridged heterodimer cytochrome b559 (Cyt b559) plays critical roles in the protection and assembly of PSII. However, the underlying mechanisms of Cyt b559 assembly are largely unclear. Here, we characterized the Arabidopsis (Arabidopsis thaliana) rph1 (resistance to Phytophthora1) mutant, which was previously shown to be susceptible to the oomycete pathogen Phytophthora brassicae. Loss of RPH1 leads to a drastic reduction in PSII accumulation, which can be primarily attributed to the defective formation of Cyt b559. Spectroscopic analyses showed that the heme level in PSII supercomplexes isolated from rph1 is significantly reduced, suggesting that RPH1 facilitates proper heme assembly in Cyt b559. Due to the loss of RPH1-mediated processes, a covalently bound PsbE-PsbF heterodimer is formed during the biogenesis of PSII. In addition, rph1 is highly photosensitive and accumulates elevated levels of reactive oxygen species under photoinhibitory-light conditions. RPH1 is a conserved intrinsic thylakoid protein present in green algae and terrestrial plants, but absent in Synechocystis, and it directly interacts with the subunits of Cyt b559. Thus, our data demonstrate that RPH1 represents a chloroplast acquisition specifically promoting the efficient assembly of Cyt b559, probably by mediating proper heme insertion into the apo-Cyt b559 during the initial phase of PSII biogenesis.

Superdiffusive Rotation of Interfacial Water on Noble Metal Surface.

Interfacial water on a metal surface acts as an active layer through the reorientation of water, thereby facilitating the energy transfer and chemical reaction across the metal surface in various physicochemical and industrial processes. However, how this active interfacial water collectively behaves on flat noble metal substrates remains largely unknown due to the experimental limitation in capturing librational vibrational motion of interfacial water and prohibitive computational costs at the first-principles level. Herein, by implementing a machine-learning approach to train neural network potentials, we enable performing advanced molecular dynamics simulations with ab initio accuracy at a nanosecond scale to map the distinct rotational motion of water molecules on a metal surface at room temperature. The vibrational density of states of the interfacial water with two-layer profiles reveals that the rotation and vibration of water within the strong adsorption layer on the metal surface behave as if the water molecules in the bulk ice, wherein the O-H stretching frequency is well consistent with the experimental results. Unexpectedly, the water molecules within the adjacent weak adsorption layer exhibit superdiffusive rotation, contrary to the conventional diffusive rotation of bulk water, while the vibrational motion maintains the characteristic of bulk water. The mechanism underlying this abnormal superdiffusive rotation is attributed to the translation-rotation decoupling of water, in which the translation is restrained by the strong hydrogen bonding within the bilayer interfacial water, whereas the rotation is accelerated freely by the asymmetric water environment. This superdiffusive rotation dynamics may elucidate the experimentally observed large fluctuation of the potential of zero charge on Pt and thereby the conventional Helmholtz layer model revised by including the contribution of interfacial water orientation. The surprising superdiffusive rotation of vicinal water next to noble metals will shed new light on the physicochemical processes and the activity of water molecules near metal electrodes or catalysts.

Conformation-Driven Responsive 1D and 2D Lanthanide-Metal-Organic Framework Heterostructures for High-Security Photonic Barcodes.

Development of luminescent segmented heterostructures featuring multiple spatial-responsive blocks is important to achieve miniaturized photonic barcodes toward anti-counterfeit applications. Unfortunately, dynamic manipulation of the spatial color at micro/nanoscale still remains a formidable challenge. Here, a straightforward strategy is proposed to construct spatially varied heterostructures through amplifying the conformation-driven response in flexible lanthanide-metal-organic frameworks (Ln-MOFs), where the thermally induced minor conformational changes in organic donors dramatically modulate the photoluminescence of Ln acceptors. Notably, compositionally and structurally distinct heterostructures (1D and 2D) are further constructed through epitaxial growth of multiple responsive MOF blocks benefiting from the isomorphous Ln-MOF structures. The thermally controlled emissive colors with distinguishable spectra carry the fingerprint information of a specific heterostructure, thus allowing for the effective construction of smart photonic barcodes with spatially responsive characteristics. The results will deepen the understanding of the conformation-driven responsive mechanism and also provide guidance to fabricate complex stimuli-responsive hierarchical microstructures for advanced optical recording and high-security labels.

One-Pot Three-Component Reaction for the Synthesis of 3,4-Dihydroquinazolines and Quinazolin-4(3H)-ones.

A highly efficient and straightforward one-pot synthesis of diversely substituted 3,4-dihydroquinazolines and quinazolin-4(3H)-ones has been achieved through a domino three-component assembly reaction of arenediazonium salts, nitriles, and bifunctional aniline derivatives. This new protocol involves three C-N bond formations through the initial formation of N-arylnitrilium intermediates from arenediazonium salts and nitriles, followed by the sequential nucleophilic addition and cyclization reactions with bifunctional anilines, leading to such N-heterocyclic compounds of biological and pharmacological importance. This method offers a simple, expedient, and robust approach with the use of amenable and easily accessible reactants/reagents under metal-free mild conditions, good functional group tolerance, and high efficiency. The synthetic applications were also demonstrated by derivatization of the products obtained from these processes and syntheses of a diverse range of valuable polycyclic N-heterocycles.

Causal relationship between varicose veins and mean corpuscular hemoglobin concentration based on Mendelian randomization study.

BACKGROUND: Increased hemoglobin concentrations may increase the risk of varicose veins. However, the underlying relationship between them was not yet understood. METHODS: Mendelian randomization (MR) analysis was performed to investigate causal effect between mean corpuscular hemoglobin concentration (MCHC, exposure factor) and varicose veins (outcome). Afterward, sensitivity analysis was used to ensure the reliability of MR analysis results. Then Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of SNPs were performed. A search tool for recurring instances of neighbouring genes (STRING) database was used to construct a protein-protein interaction (PPI) network. RESULTS: Therefore, the inverse-variance weighted (IVW) results showed there existed a causal relationship between MCHC and varicose veins (p = 0.0026), with MCHC serving as a significant risk factor. (odd ratio [OR] = 1.2321). In addition, the validity of the results of the forward MR analysis was verified by sensitivity analysis. Further, a PPI network of 92 single-nucleotide polymorphisms (SNPs) which used for forward MR analysis related genes was constructed. And they were found to be closely associated with the peroxisome proliferator-activated receptor (PPAR) signalling pathway and cellular response to external stimulus by enrichment analysis. In addition, we clarified that the effect of varicose veins on MCHC was minimal by reverse MR analysis, suggesting that the results of forward MR analysis were not disturbed by reverse results. CONCLUSION: This study found a causal relationship between varicose veins and MCHC, which provided strong evidence for the effect of hemoglobin on varicose veins, and a new thought for the diagnosis and prevention of varicose veins in the future.

The Inhibition of Bruton Tyrosine Kinase Alleviates Acute Liver Failure via Downregulation of NLRP3 Inflammasome.

There is no effective treatment for acute liver failure (ALF) except for an artificial liver support system (ALSS) and liver transplant. Bruton tyrosine kinase (Btk) plays important immunoregulatory roles in the inflammatory diseases, but its possible function in ALF remains to be characterized. In this study, we detected the phosphorylation level of Btk in ALF mouse liver and analyzed the protective effects of Btk inhibitor on survival rate and liver damage in ALF mouse models. We measured the expression levels of various inflammatory cytokines in the ALF mouse liver and primary human monocytes. In addition, we examined the expression of the NLRP3 inflammasome in mouse models with or without Btk inhibition. Clinically, we observed the dynamic changes of Btk expression in PBMCs of ALSS-treated patients. Our results showed that Btk was upregulated significantly in the experimental ALF mouse models and that Btk inhibition alleviated liver injury and reduced the mortality in these models. The protective effect of Btk inhibitors on ALF mice partially depended on the suppression of NLRP3 inflammasome signaling. Clinical investigations revealed that the dynamic changes of Btk expression in PBMCs could predict the effect of ALSS treatment. Our work shows that Btk inhibition is an effective therapeutic strategy for ALF. Moreover, Btk is a useful indicator to predict the therapeutic effect of ALSS on liver failure, which might have great value in clinical practice.

TRMT13 inhibits the growth of papillary thyroid cancer by targeting ANAPC4.

The recently discovered gene TRMT13 encodes a type of RNA methylase and is a member of the CCDC family (also called CCDC76). Here, we delineate its role in papillary thyroid cancer (PTC). Bioinformatics analysis shows significant TRMT13 and ANAPC4 downregulation in PTC and reveals that the expression levels of both genes are linearly correlated. Subsequent analyses confirm that both TRMT13 and ANAPC4 expressions are downregulated in PTC tissues and that this change in expression has a significant impact on cancer diagnosis. We conduct assays on PTC cells subjected to TRMT13 and ANAPC4 silencing or overexpression to assess the biological effects of these genes. We also perform rescue experiments to validate the regulatory effects of TRMT13 on ANAPC4. A nude mouse tumor model is used to evaluate the effects of TRMT13 and ANAPC4 on PTC tumorigenesis. TRMT13 expression is decreased in PTC tissues and cell lines and is positively correlated with that of ANAPC4. Cell assays reveal that TRMT13/ANAPC4 attenuates the malignancy of PTC cells by restraining cell proliferation, migration and invasion, while rescue experiments corroborate that ANAPC4 is a downstream target of TRMT13. In the nude mouse xenograft model, both TRMT13 and ANAPC4 inhibit tumor growth, and TRMT13 and ANAPC4 expression levels are significantly associated with survival. Taken together, these findings lead to the conclusion that TRMT13 inhibits PTC growth via ANAPC4, indicating a new role of TRMT13 and providing insights into the tRNA methyltransferase and coiled-coil domain-containing protein families.

Conductive Metal-Organic Framework Microelectrodes Regulated by Conjugated Molecular Wires for Monitoring of Dopamine in the Mouse Brain.

Herein, we demonstrated a strategy to regulate the conductive metal-organic framework (MOF) surface, by the conjugated molecule wires for selective and sensitive determination of dopamine (DA) in the live brain. The MOFs were decorated at the carbon fiber electrode deposited by Au nanoleaves as the upper electric transducer to provide rich electrocatalytic sites for electron transfer of neurochemicals at the electrode surface, leading to greatly enhanced sensitivity for detection of neurochemicals. On the other hand, the conjugated molecular wire, 4-(thiophen-3-ylethynyl)-benzaldehyde (RP1), was synthesized and assembled as an underlying bridge to regulate the electrochemical processes at the MOF-based electrode, specifically decreasing the reaction Gibbs free energy of DA oxidation, thus selectively promoting the heterogeneous electron transfer of DA from the MOF layer to the electrode surface. Owing to the electrocatalytic activity for DA oxidation, the present microsensor exhibited high selectivity for real-time tracking of DA in a good linear relationship in the range of 0.004-0.4 µM with a detection limit of 1 nM. Eventually, this functionalized electrode was successfully applied for in vivo monitoring of DA in mouse brains with Parkinson's disease (PD) model. The results indicated that the levels of DA were obviously decreased in both acute and subacute PD models. Moreover, the level of DA strongly depended on the amount of uric acid (UA), a physiological antioxidant, which rose as the UA amount was lower than 200 mg kg-1 but was downregulated again after treatment by a higher amount of UA.

TTI1 promotes non-small-cell lung cancer progression by regulating the mTOR signaling pathway.

The role of TELO2-interacting protein 1 (TTI1) in the progression of several types of cancer has been reported recently. The aim of this study was to estimate the expression and potential value of TTI1 in non-small-cell lung cancer (NSCLC) patients. The expression of TTI1 and its prognostic value in NSCLC from The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) database were analyzed. To verify the bioinformatics findings, a tissue microarray containing 160 NSCLC and paired peritumoral tissues from NSCLC patients was analyzed by immunohistochemistry for TTI1. Subsequently, the roles of TTI1 in NSCLC cells were investigated in vivo by establishing xenograft models in nude mice and in vitro by transwell, CCK-8, wound healing, and colony formation assays. In addition, quantitative real-time polymerase chain reaction and western blot were applied to explore the underlying mechanism by which TTI1 promotes tumor progression. Finally, the relationship between TTI1 and Ki67 expression level in NSCLC was probed, and Kaplan-Meier and Cox analyses were performed to assess the prognostic merit of TTI1 and Ki67 in NSCLC patients. We found that the expression of TTI1 was significantly upregulated in NSCLC tissues compared to paired peritumoral tissues, which coincides with the bioinformatics findings from the TCGA and GEO databases. TTI1 was highly expressed in NSCLC patients with large tumors, advanced tumor stage, and lymphatic metastasis. In addition, the prognostic analysis identified TTI1 as an independent indication for poor prognosis of NSCLC patients. In vitro, upregulation of TTI1 in NSCLC cells could facilitate cell invasion, metastasis, viability, and proliferation. Mechanistically, our study verified that TTI1 could regulate mTOR activity, which has a pivotal role in human cancer. Consistently, the expressions of TTI1 and Ki67 had a positive relationship in NSCLC cells and tissues. Notably, patients with overexpression of TTI1 or Ki67 had a shorter overall survival rate and a higher disease-free survival rate compared to patients with low expression of TTI1 or Ki67, and the combination of TTI1 and Ki67 was an independent parameter predicting the prognosis and recurrence of NSCLC patients. We conclude that TTI1 promotes NSCLC cell proliferation, metastasis, and invasion by regulating mTOR activity, and the combination of TTI1 and Ki67 is a valuable molecular biomarker for the survival and recurrence of NSCLC patients.

Barcode-structured YAG:Ce/YAG:Ce,Mn ceramic phosphors for variable CCT and high CRI LED/LD lighting.

Ceramic phosphors are widely considered the next-generation phosphor material for white LED/LD lighting, and a wide spectrum is a key factor in improving the CRI of lighting sources. In this paper, a novel, to our knowledge, barcode-structured YAG:Ce/YAG:Ce,Mn ceramic phosphor was designed and fabricated. The lighting sources with the CRI value of 73.5 and 68.9 were obtained under the excitation of blue LEDs and blue LDs, respectively. Simultaneously, thanks to the effective supplementary emission from a red LD, the CRI of the ceramic-based lighting source reached 81.8 under blue LD excitation. Specifically, the microstructure and luminescent property of ceramic phosphors with different thicknesses and ion doping concentrations were systematically studied. Besides, by changing the blue power from 0.52 W to 2.60 W, the CCT of the laser lighting source with the encapsulation of optimized YAG:Ce/YAG:Ce,Mn ceramic phosphors ranged from 3928 K to 5895 K, while the CRI always maintained above 80. The above results indicate that barcode-structured Ce:YAG/Ce,MnYAG ceramic phosphor is a candidate to achieve a high CRI and ican be applied to various lighting occasions.

Impact of coronary artery disease on clinical outcomes after TAVR: Insights from the BRAVO-3 randomized trial.

OBJECTIVE: To determine the prognostic impact of coronary artery disease (CAD) in patients randomized to bivalirudin or unfractionated heparin (UFH) during transcatheter aortic valve replacement (TAVR). BACKGROUND: CAD is a common comorbidity among patients undergoing TAVR and studies provide conflicting data on its prognostic impact. METHODS: The Bivalirudin on Aortic Valve Intervention Outcomes-3 (BRAVO-3) randomized trial compared the use of bivalirudin versus UFH in 802 high-surgical risk patients undergoing transfemoral TAVR for severe symptomatic aortic stenosis. Patients were stratified according to the presence or absence of history of CAD as well as periprocedural anticoagulation. The coprimary endpoints were net adverse cardiac events (NACE; a composite of all-cause mortality, myocardial infarction, stroke, or major bleeding) and major Bleeding Academic Research Consortium (BARC) bleeding ≥3b at 30 days postprocedure. RESULTS: Among 801 patients, 437 (54.6%) had history of CAD of whom 223 (51.0%) received bivalirudin. There were no significant differences in NACE (adjusted odds ratio [OR]: 1.04; 95% confidence interval [CI]: 0.69-1.58) or BARC ≥ 3b bleeding (adjusted OR: 0.84; 95% CI: 0.51-1.39) in patients with vs without CAD at 30 days. Among CAD patients, periprocedural use of bivalirudin was associated with similar NACE (OR: 0.80; 95% CI: 0.47-1.35) and BARC ≥ 3b bleeding (OR: 0.64; 95% CI: 0.33-1.25) compared with UFH, irrespective of history of CAD (p-interaction = 0.959 for NACE; p-interaction = 0.479 for major bleeding). CONCLUSION: CAD was not associated with a higher short-term risk of NACE or major bleeding after TAVR. Periprocedural anticoagulation with bivalirudin did not show any advantage over UFH in patients with and without CAD.

Spatially Resolved Organic Whispering-Gallery-Mode Hetero-Microrings for High-Security Photonic Barcodes.

Whispering-gallery-mode (WGM) microcavities featuring distinguishable sharp peaks in a broadband exhibit enormous advantages in the field of miniaturized photonic barcodes. However, such kind of barcodes developed hitherto are primarily based on microcavities wherein multiple gain medias were blended into a single matrix, thus resulting in the limited and indistinguishable coding elements. Here, a surface tension assisted heterogeneous assembly strategy is proposed to construct the spatially resolved WGM hetero-microrings with multiple spatial colors along its circular direction. Through precisely regulating the charge-transfer (CT) strength, full-color microrings covering the entire visible range were effectively acquired, which exhibit a series of sharp and recognizable peaks and allow for the effective construction of high-quality photonic barcodes. Notably, the spatially resolved WGM hetero-microrings with multiple coding elements were finally acquired through heterogeneous nucleation and growth controlled by the directional diffusion between the hetero-emulsion droplets, thus remarkably promoting the security strength and coding capacity of the barcodes. The results would be useful to fabricate new types of organic hierarchical hybrid WGM heterostructures for optical information recording and security labels.

The circular RNA circHMGB2 drives immunosuppression and anti-PD-1 resistance in lung adenocarcinomas and squamous cell carcinomas via the miR-181a-5p/CARM1 axis.

BACKGROUND: Previous studies have confirmed the oncogenic role of HMGB2 in various cancers, but the biological functions of HMGB2-derived circRNAs remain unknown. Thus, we intended to investigate the potential role of HMGB2-derived circRNAs in lung adenocarcinomas (LUAD) and squamous cell carcinomas (LUSC). METHODS: The expression profiles of HMGB2-derived circRNAs in LUAD and LUSC tissues and matched normal tissues were assessed using qRT-PCR. The role of circHMGB2 in the progression of the LUAD and LUSC was determined in vitro by Transwell, CCK-8, flow cytometry and immunohistochemistry assays, as well as in vivo in an immunocompetent mouse model and a humanized mouse model. In addition, in vivo circRNA precipitation assays, luciferase reporter assays and RNA pulldown assays were performed to explore the underlying mechanism by which circHMGB2 promotes anti-PD-1 resistance in the LUAD and LUSC. RESULTS: The expression of circHMGB2 (hsa_circ_0071452) was significantly upregulated in NSCLC tissues, and survival analysis identified circHMGB2 as an independent indicator of poor prognosis in the LUAD and LUSC patients. We found that circHMGB2 exerted a mild effect on the proliferation of the LUAD and LUSC cells, but circHMGB2 substantially reshaped the tumor microenvironment by contributing to the exhaustion of antitumor immunity in an immunocompetent mouse model and a humanized mouse model. Mechanistically, circHMGB2 relieves the inhibition of downstream CARM1 by sponging miR-181a-5p, thus inactivating the type 1 interferon response in the LUAD and LUSC. Moreover, we found that the upregulation of circHMGB2 expression decreased the efficacy of anti-PD-1 therapy, and we revealed that the combination of the CARM1 inhibitor EZM2302 and an anti-PD-1 antibody exerted promising synergistic effects in a preclinical model. CONCLUSION: circHMGB2 overexpression promotes the LUAD and LUSC progression mainly by reshaping the tumor microenvironment and regulating anti-PD-1 resistance in the LUAD and LUSC patients. This study provides a new strategy for the LUAD and LUSC treatment.

Al2O3-YAG:Ce/YAG composite ceramic phosphor in a transmissive configuration for high-brightness laser-driven lighting.

High-power, high-brightness laser lighting promotes new requirements for light-conversion materials, such as high thermal conductivity, high saturation threshold and compact encapsulation. In this paper, we designed and fabricated a novel composite structure ceramic including a 1.0 × 1.0 mm2 Al2O3-YAG:Ce ceramic and a φ=16.0 mm transparent YAG ceramic for the transmissive configuration in laser lighting. When pumped by blue laser from 0∼60 W mm2, all the samples exhibited no luminous saturation phenomenon, and the 10.0 wt.%Al2O3-YAG:Ce/YAG composite ceramic with the thickness of 0.3 mm maintained white light with a luminous efficacy over 200 lm/W. Moreover, a maximal luminous flux over 1000 lm, a correlated color temperature (CCT) of 5471 K, and an operating temperature as low as 92.3 °C were obtained under the excitation power density as high as 60 W/mm2. The configuration that Al2O3-YAG:Ce encapsulated by YAG reflects an excellent optical and thermal properties by using transparent and highly thermally conductive YAG materials. These results indicate that Al2O3-YAG:Ce/ YAG composite ceramic phosphor is a promising candidate in transmissive configuration for automotive lighting and laser searchlight.

A single dose of self-transcribing and replicating RNA-based SARS-CoV-2 vaccine produces protective adaptive immunity in mice.

A self-transcribing and replicating RNA (STARR)-based vaccine (LUNAR-COV19) has been developed to prevent SARS-CoV-2 infection. The vaccine encodes an alphavirus-based replicon and the SARS-CoV-2 full-length spike glycoprotein. Translation of the replicon produces a replicase complex that amplifies and prolongs SARS-CoV-2 spike glycoprotein expression. A single prime vaccination in mice led to robust antibody responses, with neutralizing antibody titers increasing up to day 60. Activation of cell-mediated immunity produced a strong viral antigen-specific CD8+ T lymphocyte response. Assaying for intracellular cytokine staining for interferon (IFN)γ and interleukin-4 (IL-4)-positive CD4+ T helper (Th) lymphocytes as well as anti-spike glycoprotein immunoglobulin G (IgG)2a/IgG1 ratios supported a strong Th1-dominant immune response. Finally, single LUNAR-COV19 vaccination at both 2 µg and 10 µg doses completely protected human ACE2 transgenic mice from both mortality and even measurable infection following wild-type SARS-CoV-2 challenge. Our findings collectively suggest the potential of LUNAR-COV19 as a single-dose vaccine.

Molecular detection of haemophilic pathogens reveals evidence of Candidatus Mycoplasma haemobos in dogs and parasitic ticks in central China.

BACKGROUND: In addition to Mycoplasma haemocanis and Candidatus Mycoplasma haematoparvum, a few hemoplasma species that mainly infect other livestock have been detected in dogs. 'Candidatus Mycoplasma haemobos' (Ca. M. haemobos) has been found in a variety of animals in China. The present study was aimed to investigate the occurrence of 'Ca. M. haemobos' infections in dogs and ticks collected from the Henan province, China. RESULTS: Overall, 55 dog blood samples and 378 ticks on skins were collected from anemic and healthy dogs, and these samples were subjected to PCR, sequence analysis, and identification. The results showed that Haemaphysalis longicornis (266) and Rhipicephalus (Boophilus) microplus (112) were the only two parasitic ticks on dogs. Molecular detection revealed that 163 M. haemocanis, 88 'Ca. M. haemobos' and 32 Anaplasma platys positive amplicons could be amplified from dogs, H. longicornis and R. (B.) microplus. In addition, co-infections (M. haemocanis + A. platys and 'Ca. M. haemobos'+ A. platys) could be also detected. CONCLUSIONS: To the best of our knowledge, this is the first molecular evidence of 'Ca. M. haemobos' natural infection in dogs and tick species identified as H. longicornis and R. (B.) microplus from China.

Student assistantship programme: an evaluation of impact on readiness to transit from medical student to junior doctor.

BACKGROUND: Studies report that medical graduates are not prepared for practice as expected, and interventions have been developed to prepare them for practice. One such intervention is the assistantship, which provides hands-on opportunities to hone clinical skills and undertake responsibilities under supervision. The Lee Kong Chian School of Medicine (LKCMed) is Singapore's newest medical school, and students undergo a Student Assistantship Programme (SAP) to prepare for practice as junior doctors (PGY1). This study evaluated the SAP from the students' and clinical supervisors' perspectives. METHODS: Students completed online questionnaires to assess readiness for practice before and after SAP, and a subsample were interviewed about their experiences of SAP and its impact on their preparedness for PGY1. In addition, after our graduates had begun work as PGY1 doctors, their clinical supervisors completed an online questionnaire and were interviewed about the perceived benefits of SAP and the attributes of our graduates as junior doctors. RESULTS: Fifty (96%) students completed the pre-SAP questionnaire and 46 (92%) completed the post-SAP questionnaire. Levels of preparedness increased post-SAP (mean scores range pre-SAP: 2.38 to 4.32 vs post-SAP: 3.08 to 4.48); so did opportunities to undertake PGY1 duties (pre-SAP: 56% vs post-SAP: 96%), and hands-on experience in medical emergencies (pre-SAP: 76% vs post-SAP: 89%).Experience of acute care situations increased except "paracetamol overdose". Readiness to be first respondents in ten acute situations improved (statistically significant for asthma, chronic obstructive pulmonary disease exacerbation, gastrointestinal bleed, sepsis, and adverse drug reactions). Three themes emerged from twenty-five student interviews: learning about the work environment, opportunities to learn in a safe environment, and enhancing SAP for future students. Thirty-three supervisors completed the questionnaire, and 70% rated SAP positively in preparing students for PGY1. Eight supervisors interviewed shared positively about the content, timing, and duration of SAP; and suggested future SAPs help students to develop coping and reflective skills. CONCLUSIONS: The SAP improved students' preparedness and experience across clinical areas, and students felt the SAP helped bridge undergraduate curriculum and work, provided opportunities to hone their skills and learn from junior doctors. Most clinical supervisors rated the SAP effective in preparing students for PGY1. This is the first formal evaluation of an assistantship in Singapore, and the findings are encouraging from the perspective of students and PGY1 supervisors.

Dissipative Particle Dynamics Simulation of the Sensitive Anchoring Behavior of Smectic Liquid Crystals at Aqueous Phase.

Rational design of thermotropic liquid crystal (LC)-based sensors utilizing different mesophases holds great promise to open up novel detection modalities for various chemical and biological applications. In this context, we present a dissipative particle dynamics study to explore the unique anchoring behavior of nematic and smectic LCs at amphiphile-laden aqueous-LC interface. By increasing the surface coverage of amphiphiles, two distinct anchoring sequences, a continuous planar-tilted-homeotropic transition and a discontinuous planar-to-homeotropic transition, can be observed for the nematic and smectic LCs, respectively. More importantly, the latter occurs at a much lower surface coverage of amphiphiles, demonstrating an outstanding sensitivity for the smectic-based sensors. The dynamics of reorientation further reveals that the formation of homeotropic smectic anchoring is mainly governed by the synchronous growth of smectic layers through the LCs, which is significantly different from the mechanism of interface-to-bulk ordering propagation in nematic anchoring. Furthermore, the smectic LCs have also been proven to possess a potential selectivity in response to a subtle change in the chain rigidity of amphiphiles. These simulation findings are promising and would be valuable for the development of novel smectic-based sensors.

Cancer cell-derived exosomal circUSP7 induces CD8+ T cell dysfunction and anti-PD1 resistance by regulating the miR-934/SHP2 axis in NSCLC.

BACKGROUND: CD8+ T cells play a critical role in the innate antitumour immune response. Recently, CD8+ T cell dysfunction has been verified in various malignant cancers, including non-small cell lung cancer (NSCLC). However, the molecular biological mechanisms of CD8+ T cell dysfunction in human NSCLC are still unclear. METHODS: The expression of circular ubiquitin-specific protease-7 (circUSP7) in NSCLC tissues, exosomes, and cell lines was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Exosomes were isolated from the culture medium of NSCLC cells and the plasma of NSCLC patients using an ultracentrifugation method and the ExoQuick Exosome Precipitation Solution kit. The exosomes were then characterized by transmission electronic microscopy (TEM), NanoSight and western blotting. The role of circUSP7 in CD8+ T cell dysfunction was assessed by enzyme-linked immunosorbent assay (ELISA). In vivo circular RNA (circRNA) precipitation (circRIP), RNA immunoprecipitation (RIP), and luciferase reporter assays were performed to explore the molecular mechanisms of circUSP7 in CD8+ T cells. In a retrospective study, the clinical characteristics and prognostic significance of circUSP7 in NSCLC tissues were determined. RESULTS: The expression levels of circUSP7 were higher in human NSCLC tissues than in matched adjacent nontumour tissues. Increased levels of circUSP7 indicate poor clinical prognosis and CD8+ T cell dysfunction in patients with NSCLC. The circUSP7 found in NSCLC patient plasma is predominantly secreted by NSCLC cells in an exosomal manner, and circUSP7 inhibits IFN-γ, TNF-α, Granzyme-B and Perforin secretion by CD8+ T cells. Furthermore, circUSP7 inhibits CD8+ T cell function by upregulating the expression of Src homology region 2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2) via sponging miR-934. Finally, we show that circUSP7 may promote resistance to anti-PD1 immunotherapy in NSCLC patients. CONCLUSIONS: Exosomal circUSP7 is predominantly secreted by NSCLC cells and contributes to immunosuppression by promoting CD8+ T cell dysfunction in NSCLC. CircUSP7 induces resistance to anti-PD1 immunotherapy, providing a potential therapeutic strategy for NSCLC patients.