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Zhang, T.

Publications and source records attributed to Zhang, T..

At least 541 records · Page 30Linked to original sources

Inter-determination of blood metabolite levels and gut microbiome supported by Mendelian randomization

The gut microbiome has been implicated in a variety of physiological states, but controversy over causality remains unresolved. Here, we performed bidirectional Mendelian randomization (MR) analyses on 3,432 Chinese individuals with whole genome, whole metagenome, anthropometric, and blood metabolic trait data. We identified 58 causal relationships between the gut microbiome and blood metabolites, and replicated 43 of them. Increased relative abundances of fecal Oscillibacter and Alistipes were causally linked to decreased triglyceride concentration. Conversely, blood metabolites such as glutamic acid appeared to decrease fecal Oxalobacter, and members of Proteobacteria were influenced by metabolites such as 5-methyltetrahydrofolic acid, alanine, glutamate, and selenium. Two-sample MR with data from Biobank Japan partly corroborated results with triglyceride and with uric acid, and also provided causal support for published fecal bacterial markers for cancer and cardiovascular diseases. This study illustrates the value of human genetic information to help prioritize gut microbial features for mechanistic and clinical studies.

genetics↗

Impact of trimethoprim on the river microbiome and antimicrobial resistance.

Recent evidence suggests that anthropogenic activity can increase the levels of antimicrobial resistance (AMR) in the environment. Rivers and waterways are significant examples of environmental settings that have become repositories of antibiotics and antibiotic resistance genes (ARGs). Our recent study quantified drug concentrations in freshwater samples taken at a range of sites located on the Thames catchment; the highest levels of antibiotics and other drugs were recorded downstream of waste water treatment plants (WWTPs). One specific antibiotic: Trimethoprim (TMP) was shown at elevated concentrations reaching 2000ng/L at particular sites. We have also shown a correlative relationship between the residue of TMP and the prevalence of sulfonamide antibiotic resistance genes such as sul1. Despite this, there is still no evidence of a causative relationship between TMP concentrations and the prevalence of the ARGs at river sites. The aim of the current study was to conduct in-depth analysis using a combination of large metagenomic, geospatial and chemical datasets, in order to conduct a comparison between those sites with the highest TMP and lowest TMP levels across the Thames catchment. We aimed to establish the proximity of these sites to WWTPs, their population equivalence (PE) and land coverage. A secondary aim was to investigate seasonal variation in TMP and ARGs. Exploring these factors will help to decipher the clinical relevance of ARG accumulation at river sites. A significant correlation was shown between TMP levels at river sites and their distance downstream from a WWTP. Three sites located on the Rivers Cut and Ray showed significantly higher TMP concentrations in winter compared to summer. The population equivalence (PE) for sites with the highest TMP levels was significantly higher than those with the lowest levels. The land coverage of sites with the highest TMP levels was significantly more urban/suburban than sites with the lowest TMP concentrations, which were found to be significantly more arable. Five ARGs relevant to TMP and sulfonamides were identified across the Thames catchment. The most prevalent ARG was sul1, which was significantly more prevalent in winter compared to summer. By contrast sul2 was found to be significantly more prevalent in summer compared to winter at a site on the River Coln. The prevalence of the class 1 integron marker gene (inti1) did not differ significantly by season or between sites with the highest/lowest TMP levels.

microbiology↗

Infection Groups Differential (IGD) Score Reveals Infection Ability Difference between SARS-CoV-2 and Other Coronaviruses

The Corona Virus Disease 2019 (COVID-19) pandemic that began in late December 2019 has resulted in millions of cases diagnosed worldwide. Reports have shown that SARS-CoV-2 shows extremely higher infection rates than other coronaviruses. This study conducted a phylogenetics analysis of 91 representative coronaviruses and found that the functional spike protein of SARS-CoV-2, which interacts with the human receptor ACE2, is actually not undergoing distinct selection pressure compared to other coronaviruses. Furthermore, we define a new measurement, infection group differential (IGD) score, in assessing the infection ability of two human coronavirus groups. There are nine extremely high IGD (ehIGD) sites in the receptor-binding domain (RBD) out of 40 high IGD (hIGD) sites that exhibit a unique infection-related pattern from the haplotype network and docking energy comparison. These 40 hIGD sites are basically conserved among the SARS-CoV-2, i.e. there are only two hIGD sites mutated in four out of 1,058 samples, defined as rare-mutation hIGD (rhIGD) sites. In conclusion, ehIGD and rhIGD sites might be of great significance to the development of vaccines.

bioinformatics↗

Multiple expression assessments of ACE2 and TMPRSS2 SARS-CoV-2 entry molecules in the urinary tract and their associations with clinical manifestations of COVID-19

BackgroundSince December 2019, the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first spread quickly in Wuhan, China, then globally. From previously published evidence, ACE2 and TMPRSS2, are both pivotal entry molecules that enable cellular infection by SARS-CoV-2. Meanwhile, increased expression of pro-inflammatory cytokines, or a "cytokine storm," is associated with multiple organ dysfunction syndrome that is often observed in critically ill patients. MethodsWe investigated the expression pattern of ACE2 and TMPRSS2 in major organs in the human body, especially under specific disease conditions. Multiple sequence alignment of ACE2 in different species was used to explain animal susceptibility. Moreover, the cell-specific expression patterns of ACE2 and cytokine receptors in the urinary tract were assessed using single-cell RNA sequencing (scRNA-seq). Additional biological relevance was determined through Gene Set Enrichment Analysis (GSEA) using an ACE2 specific signature. ResultsOur results revealed that ACE2 and TMPRSS2 were highly expressed in genitourinary organs. ACE2 was highly and significantly expressed in the kidney among individuals with chronic kidney diseases or diabetic nephropathy. In single cells, ACE2 was primarily enriched in gametocytes in the testis, and renal proximal tubules. The receptors for pro-inflammatory cytokines, especially IL6ST, were remarkably concentrated in endothelial cells, macrophages, and spermatogonial stem cells in the testis, and renal endothelial cells, which suggested the occurrence of alternative damaging mechanisms via autoimmune attacks. ConclusionsThis study provided new insights into the pathogenicity mechanisms of SARS-CoV-2 that underlie the clinical manifestations observed in the human testis and kidney. These observations might substantially facilitate the development of effective treatments for this rapidly spreading disease.

biochemistry↗

Identification of Candidate COVID-19 Therapeutics using hPSC-derived Lung Organoids

Summary ParagraphThe SARS-CoV-2 virus has caused already over 3.5 million COVID-19 cases and 250,000 deaths globally. There is an urgent need to create novel models to study SARS-CoV-2 using human disease-relevant cells to understand key features of virus biology and facilitate drug screening. As primary SARS-CoV-2 infection is respiratory-based, we developed a lung organoid model using human pluripotent stem cells (hPSCs) that could be adapted for drug screens. The lung organoids, particularly aveolar type II cells, express ACE2 and are permissive to SARS-CoV-2 infection. Transcriptomic analysis following SARS-CoV-2 infection revealed a robust induction of chemokines and cytokines with little type I/III interferon signaling, similar to that observed amongst human COVID-19 pulmonary infections. We performed a high throughput screen using hPSC-derived lung organoids and identified FDA-approved drug candidates, including imatinib and mycophenolic acid, as inhibitors of SARS-CoV-2 entry. Pre- or post-treatment with these drugs at physiologically relevant levels decreased SARS-CoV-2 infection of hPSC-derived lung organoids. Together, these data demonstrate that hPSC-derived lung cells infected by SARS-CoV-2 can model human COVID-19 disease and provide a valuable resource to screen for FDA-approved drugs that might be repurposed and should be considered for COVID-19 clinical trials.

microbiology↗

Identification of Drugs Blocking SARS-CoV-2 Infection using Human Pluripotent Stem Cell-derived Colonic Organoids

Summary ParagraphThe current COVID-19 pandemic is caused by SARS-coronavirus 2 (SARS-CoV-2). There are currently no therapeutic options for mitigating this disease due to lack of a vaccine and limited knowledge of SARS-CoV-2 biology. As a result, there is an urgent need to create new disease models to study SARS-CoV-2 biology and to screen for therapeutics using human disease-relevant tissues. COVID-19 patients typically present with respiratory symptoms including cough, dyspnea, and respiratory distress, but nearly 25% of patients have gastrointestinal indications including anorexia, diarrhea, vomiting, and abdominal pain. Moreover, these symptoms are associated with worse COVID-19 outcomes1. Here, we report using human pluripotent stem cell-derived colonic organoids (hPSC-COs) to explore the permissiveness of colonic cell types to SARS-CoV-2 infection. Single cell RNA-seq and immunostaining showed that the putative viral entry receptor ACE2 is expressed in multiple hESC-derived colonic cell types, but highly enriched in enterocytes. Multiple cell types in the COs can be infected by a SARS-CoV-2 pseudo-entry virus, which was further validated in vivo using a humanized mouse model. We used hPSC-derived COs in a high throughput platform to screen 1280 FDA-approved drugs against viral infection. Mycophenolic acid and quinacrine dihydrochloride were found to block the infection of SARS-CoV-2 pseudo-entry virus in COs both in vitro and in vivo, and confirmed to block infection of SARS-CoV-2 virus. This study established both in vitro and in vivo organoid models to investigate infection of SARS-CoV-2 disease-relevant human colonic cell types and identified drugs that blocks SARS-CoV-2 infection, suitable for rapid clinical testing.

microbiology↗

The development trends of antineoplastics targeting PD-1/PD-L1 based on scientometrics and patentometrics

BackgroundThis paper aims to show the scientific research and technological development trends of antineoplastics targeting PD-1/PD-L1 based on scientometrics and patentometrics. Methodology/Principal FindingsPublications and patents related to antineoplastics targeting PD-1/PD-L1were searched and collected from the Web of Science (WoS) and the Derwent Innovation Index (DII) respectively. Totally, 11244 publications and 5501 patents were obtained. The publications were analyzed from the annual number, the top countries/regions and organizations to describe the scientific research trends in this field. The patents were analyzed from the annual number, the top priority countries and patent assignees to reveal the characteristics and status of technological development. As well as the identification of scientific research focus and technological development focus was based on the title and abstract of the publications and patents, using the freely available computer program VOSviewer for clustering and visualization analysis. The number of scientific publications and patent applications showed obvious increase of 29.84% and 33.46% in recent ten years (2009-2018), respectively. Results suggested that the most productive countries/regions publishing on antineoplastics targeting PD-1/PD-L1 were USA and China, and the top three productive organizations were all from USA, including Harvard University, VA Boston Healthcare System (VA BHS) and University Of California System. There were four scientific research focus: (1) immune escape mechanism, (2) biomarkers related to efficacy and prognosis, (3) immune-related adverse event, and (4) drug design and preparation, and five technological development focus: (1) testing methods and apparatus, (2) indications related to carcinoma, (3) biomarkers related to diagnosis and prognosis, (4) small molecule inhibitors, and (5) indications other than carcinoma. Conclusions/SignificanceThe results of this study presents an overview of the characteristics of research status and trends of antineoplastics targeting PD-1/PD-L1, which could help readers broaden innovative ideas and discover new technological opportunities, and also serve as important indicators for government policymaking.

biochemistry↗

Artemisia annua and Artemisia afra extracts exhibit strong bactericidal activity against Mycobacterium tuberculosis

Ethnopharmacological relevanceEmergence of drug-resistant and multidrug-resistant Mycobacterium tuberculosis (Mtb) strains is a major barrier to tuberculosis (TB) eradication, as it leads to longer treatment regimens and in many cases treatment failure. Thus, there is an urgent need to explore new TB drugs and combinations, in order to shorten TB treatment and improve outcomes. Here, we evaluate the potential of two medicinal plants, Artemisia annua, a natural source of artemisinin (AN), and Artemisia afra, as sources of novel antitubercular agents. Aim of the studyOur goal was to measure the activity of A. annua and A. afra extracts against Mtb as potential natural and inexpensive therapies for TB treatment, or as sources of compounds that could be further developed into effective treatments. Materials and MethodsThe minimum inhibitory concentrations (MICs) of A. annua and A. afra dichloromethane extracts were determined, and concentrations above the MICs were used to evaluate their ability to kill Mtb and Mycobacterium abscessus in vitro. ResultsPrevious studies showed that A. annua and A. afra inhibit Mtb growth. Here, we show for the first time that Artemisia extracts have a strong bactericidal activity against Mtb. The killing effect of A. annua was much stronger than equivalent concentrations of pure AN, suggesting that A. annua extracts kill Mtb through a combination of AN and additional compounds. A. afra, which produces very little AN, displayed bactericidal activity against Mtb that was substantial but weaker than that of A. annua. In addition, we measured the activity of Artemisia extracts against Mycobacterium abscessus. Interestingly, we observed that while A. annua is not bactericidal, it inhibits growth of M. abscessus, highlighting the potential of this plant in combinatory therapies to treat M. abscessus infections. ConclusionOur results indicate that Artemisia extracts have an enormous potential for treatment of TB and M. abscessus infections, and that these plants contain bactericidal compounds in addition to AN. Combination of extracts with existing antibiotics may not only improve treatment outcomes but also reduce the emergence of resistance to other drugs.

microbiology↗

Convergent evolution of p38/MAPK activation in hormone resistant prostate cancer mediates pro-survival, immune evasive, and metastatic phenotypes

Adaptation of cancer cells to targeted therapy follows ecological paradigms observed in natural populations that encounter resource depletion and changing environments, including activation of pro-survival mechanisms, migration to new locations, and escape of predation. We identified the p38 MAPK pathway as a common molecular driver of these three responses during the adaptation to hormone therapy resistance in prostate cancer. The p38 pathway is activated in therapy-resistant cells and mechanistically drives these three convergent responses through sustained AR activity, enhanced invasion and metastasis, and immune evasion. Targeting p38 signaling may represent a new therapeutic strategy to treat men with metastatic, hormone therapy-resistant prostate cancer.

cancer biology↗

Blocking antibodies against SARS-CoV-2 RBD isolated from a phage display antibody library using a competitive biopanning strategy

The infection of the novel coronavirus SARS-CoV-2 have caused more than 150,000 deaths, but no vaccine or specific therapeutic antibody is currently available. SARS-CoV-2 relies on its spike protein, in particular the receptor binding domain (RBD), to bind human cell receptor angiotensin-converting enzyme 2 (ACE2) for viral entry, and thus targeting RBD holds the promise for preventing SARS-CoV-2 infection. In this work, a competitive biopanning strategy of a phage display antibody library was applied to screen blocking antibodies against RBD. High-affinity antibodies were enriched after the first round using a standard panning process in which RBD-His recombinant protein was immobilized as a bait. At the next two rounds, immobilized ACE2-Fc and free RBD-His proteins were mixed with the enriched phage antibodies. Antibodies binding to RBD at epitopes different from ACE2-binding site were captured by the immobilized ACE2-Fc, forming a "sandwich" complex. Only antibodies competed with ACE2 for recognizing RBD at the same or similar epitopes can bind to the free RBD-His in the supernatant and be subsequently separated by the Ni-NTA magnetic beads. Top 1 lead from the competitive biopanning of a synthetic antibody library, Lib AB1, was produced as the full-length IgG1 format. It was proved to competitively block the binding of RBD to ACE2 protein, and potently inhibit SARS-CoV-2 pseudovirus infection of ACE2-overexpressing Hela cells with IC50 values of 12nM. Nevertheless, top 1 lead from the standard biopanning of Lib AB1, can only bind to RBD in vitro but not have the blocking or neutralization activity. Our strategy can efficiently isolate the blocking antibodies of RBD, and it would speed up the discovery of neutralizing antibodies against SARS-CoV-2.

microbiology↗

Cryo-EM structure of C9ORF72-SMCR8-WDR41 reveals the role as a GAP for Rab8a and Rab11a

A massive intronic hexanucleotide repeat (GGGGCC) expansion in C9ORF72 is a genetic origin of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recently, C9ORF72, together with SMCR8 and WDR41, has been shown to regulate autophagy and function as Rab GEF. However, the precise function of C9ORF72 remains unclear. Here, we report the cryo-EM structure of the human C9ORF72-SMCR8-WDR41 complex at a resolution of 3.2 [A]. The structure reveals the dimeric assembly of a heterotrimer of C9ORF72-SMCR8-WDR41. Notably, the C-terminal tail of C9ORF72 and the DENN domain of SMCR8 play critical roles in the dimerization of the two protomers of the C9ORF72-SMCR8-WDR41 complex. In the protomer, C9ORF72 and WDR41 are joined by SMCR8 without direct interaction. WDR41 binds to the DENN domain of SMCR8 by the C-terminal helix. Interestingly, the prominent structural feature of C9ORF72-SMCR8 resembles that of the FLNC-FNIP2 complex, the GTPase activating protein (GAP) of RagC/D. Structural comparison and sequence alignment revealed that Arg147 of SMCR8 is conserved and corresponds to the arginine finger of FLCN, and biochemical analysis indicated that the Arg147 of SMCR8 is critical to the stimulatory effect of the C9ORF72-SMCR8 complex on Rab8a and Rab11a. Our study not only illustrates the basis of C9ORF72-SMCR8-WDR41 complex assembly but also reveals the GAP activity of the C9ORF72-SMCR8 complex. Significance StatementC9ORF72, together with SMCR8 and WDR41, has been shown to form a stable complex that participates in the regulation of membrane trafficking. We report the cryo-EM structure of the C9ORF72-SMCR8-WDR41 complex at atomic resolution. Notably, the stoichiometry of the three subunits in the C9ORF72-SMCR8-WDR41 complex is 2:2:2. Interestingly, the C-termini of C9ORF72 and the DENN domain of SMCR8 mediate the dimerization of the two C9ORF72-SMCR8-WDR41 protomers in the complex. Moreover, WDR41 binds to the DENN domain of SMCR8 by the C-terminal helix without direct contact with C9ORF72. Most importantly, the C9ORF72-SMCR8 complex works as a GAP for Rab8a and Rab11a in vitro, and the Arg147 of SMCR8 is the arginine finger.

biochemistry↗

Assessment of whether published non-Cochrane systematic reviews of nursing follow the review protocols registered in the International Prospective Register of Systematic Reviews (PROSPERO): A comparative study

Purpose We compare published non-Cochrane reviews of nursing with their pre-registered protocols on PROSPERO to quantify the prevalence of differences and the extent to which the differences were explained.Methods We searched for protocols and their corresponding reviews in PROSPERO’s nursing group that were “completed and published” from inception to September 8th, 2019. Two authors independently identified differences and classified the difference as none, partial, or complete, and determined if the existed differences had been explained. Frequency (n), percentage (%), median, and inter-quartile ranges were used to analyze the extent of differences and explanations.Results We identified 22 pre-registered protocols and their reviews. All 22 pairs (100%) exhibited differences. Eighteen pairs (82%) showed differences in at least six methodological sections, while 21 pairs (95%) involved completed difference in at least one section. The median number of differences per review was 8.00 (upper quartile = 6.00, lower quartile = 9.75). The differences involved all 13 compared methodology-related sections. Only 5 (3%) of all differences were explained in the systematic reviews.Conclusions We observed widespread differences between non-Cochrane reviews of nursing and their protocols recorded in PROSPERO, with relatively few explanations for the changes. Measures including establishing a new item in the reporting guideline of systematic reviews to guide reporting and explaining the reasons for differences between protocols and systematic reviews or even requiring authors to do so at the Journal’s author guideline are recommended to improve transparency.View Full Text

scientific communication and education↗

Robust neutralization assay based on SARS-CoV-2 S-bearing vesicular stomatitis virus (VSV) pseudovirus and ACE2-overexpressed BHK21 cells

The global pandemic of Coronavirus disease 2019 (COVID-19) is a disaster for human society. A convenient and reliable in vitro neutralization assay is very important for the development of neutralizing antibodies, vaccines and other inhibitors. In this study, G protein-deficient vesicular stomatitis virus (VSVdG) bearing full-length and truncated spike (S) protein of SARS-CoV-2 were evaluated. The virus packaging efficiency of VSV-SARS-CoV-2-Sdel18 (S with C-terminal 18 amino acid truncation) is much higher than VSV-SARS-CoV-2-S. A neutralization assay for antibody screening and serum neutralizing titer quantification was established based on VSV-SARS-CoV-2-Sdel18 pseudovirus and human angiotensin-converting enzyme 2 (ACE2) overexpressed BHK21 cell (BHK21-hACE2). The experimental results can be obtained by automatically counting EGFP positive cell number at 12 hours after infection, making the assay convenient and high-throughput. The serum neutralizing titer of COVID-19 convalescent patients measured by VSV-SARS-CoV-2-Sdel18 pseudovirus assay has a good correlation with live SARS-CoV-2 assay. Seven neutralizing monoclonal antibodies targeting receptor binding domain (RBD) of SARS-CoV-2-S were obtained. This efficient and reliable pseudovirus assay model could facilitate the development of new drugs and vaccines.

microbiology↗

Siderophores provoke extracellular superoxide production by carbon-starving Arthrobacter strains when carbon sources recover

Superoxide and other reactive oxygen species (ROS) in the environment shape microbial communities1 and drive transformation of metals2,3 and inorganic/organic matter4,5. Taxonomically diverse bacteria and phytoplankton can produce extracellular superoxide during laboratory cultivation6-11. Understanding the physiological reasons for extracellular superoxide production by aerobes in the environment is a crucial question yet not fully solved. Here, we showed that iron-starving Arthrobacter sp. QXT-31 (referred to as A. QXT-31 hereafter) secreted a type of siderophore (deferoxamine, DFO), which provoked extracellular superoxide production by carbon-starving A. QXT-31 when carbon sources were recovered. Several other siderophores also demonstrated similar effects. RNA-Seq data hinted that DFO stripped iron from iron-bearing proteins in the electron transfer chain (ETC) of metabolically active A. QXT-31, resulting in electron leakage from the electron-rich (resulting from carbons source metabolism) ETC and superoxide production. Considering that most aerobes secrete siderophore(s)12 and often suffer from carbon starvation in the environment, certain aerobes are expected to produce extracellular superoxide when carbon source(s) recover/fluctuate, thus influencing the microbial community and cycling of many elements. In addition, an artificial iron-chelator (diethylenetriamine pentaacetic acid, DTPA) was widely used in microbial superoxide quantification. Our results showed that DTPA provoked superoxide production by A. QXT-31 and highlighted its potential interference in microbial superoxide quantification.

microbiology↗

Generation of neuronal diversity from common progenitors via Notch signaling in the cerebellum

Brain neurons arise from relatively few progenitors capable of giving rise to an enormous diversity of neuronal types. Nonetheless, a cardinal feature of mammalian brain neurogenesis in both the cortex and the cerebellum is that excitatory neurons and inhibitory neurons derive from separate, spatially segregated, progenitors. Whether bi-potential progenitors with an intrinsic capacity to generate both excitatory and inhibitory lineages exist and how such a fate decision may be regulated is unknown. Using cerebellar development as a model, we discover that individual embryonic cerebellar progenitors give rise to both inhibitory and excitatory lineages. We find that gradations of Notch activity levels determine the fates of the progenitors and their daughters. Daughters with the highest levels of Notch activity retain the progenitor fate. Daughters with intermediate levels of Notch activity become fate restricted to generate inhibitory neurons, while daughters with very low levels of Notch signaling adopt the excitatory fate. Therefore, Notch mediated binary cell fate choice is a mechanism for regulating the ratio of excitatory to inhibitory neurons from common progenitors. Graphical summary O_FIG O_LINKSMALLFIG WIDTH=144 HEIGHT=200 SRC="FIGDIR/small/997205v2_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@c477f8org.highwire.dtl.DTLVardef@a079bforg.highwire.dtl.DTLVardef@1992877org.highwire.dtl.DTLVardef@2fd5de_HPS_FORMAT_FIGEXP M_FIG C_FIG

developmental biology↗

CM93, a novel covalent small molecule inhibitor targeting lung cancer with mutant EGFR

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have provided successful targeted therapies for patients with EGFR-mutant non-small-cell lung cancer (NSCLC). Osimertinib (AZD9291) is a third-generation irreversible EGFR TKI that has received regulatory approval for overcoming resistance mediated by the EGFR T790M mutation as well as a first-line treatment targeting EGFR activating mutations. However, a significant fraction of patients cannot tolerate the adverse effect associated with AZD9291. In addition, brain metastases are common in patients with NSCLN and remain a major clinical challenge. Here, we report the development of a novel third-generation EGFR TKI, CM93. Compared to AZD9291, CM93 exhibits improved lung cancer targeting and brain penetration and has demonstrated promising antitumor efficacy in mouse models of both EGFR-mutant NSCLC orthotopic and brain metastases. In addition, we find that CM93 confers superior safety benefits in mice. Our results demonstrate that further evaluations of CM93 in clinical studies for patients with EGFR-mutant NSCLC and brain metastases are warranted.

pharmacology and toxicology↗

Genome-centric portrait of the microbes' cellulolytic competency

Neither the abundance of the exo/endoglucase GH modules nor the taxonomy affiliation is informative enough in inferring whether a genome is of a potential cellulolytic microbe or not. By interpreting the complete genomes of 2642 microbe strains whose phenotypes have been well documented, we are trying to reveal a more reliable genotype and phenotype correlation on the specific function niche of cellulose hydrolysis. By incorporating into the annotation approach an automatic recognition of the potential synergy machineries, a more reliable prediction on the corresponding microbes cellulolytic competency could be achieved. The potential cellulose hydrolyzing microbes could be categorized into 5 groups according to the varying synergy machineries among the carbohydrate active modules/genes annotated. Results of the meta-analysis on the 2642 genomes revealed that some cellulosome gene clusters were in lack of the surface layer homology module (SLH) and microbe strains annotated with such cellulosome gene clusters were not certainly cellulolytic. Hypothesized in this study was that cellulosome-independent genes harboring both the SLH module and the cellulose-binding carbohydrate binding module (CBM) were likely an alternative gene apparatus initiating the formation of the cellulose-enzyme-microbe (CEM) complexes; and their role is important especially for the cellulolytic anaerobes without cellulosome gene clusters. ImportanceIn the genome-centric prediction on the corresponding microbes cellulolytic activity, recognition of the synergy machineries that include but are not limited to the cellulosome gene clusters is equally important as the annotation of the individual carbohydrate active modules or genes. This is the first time that a pipeline was developed for an automatic recognition of the synergy among the carbohydrate active units annotated. With promising resolution and reliability, this pipeline should be a good add to the bioinformatic tools for the genome-centric interpretations on the specific function niche of cellulose hydrolysis.

genomics↗

Saturation of influenza virus neutralization and antibody consumption can both lead to bistable growth kinetics

Influenza virus is a major human health threat. Neutralizing antibodies elicited through prior infection or vaccination play an irreplaceable role in protection from subsequent infection. The efficacy of antibody-dependent vaccines relies on both virus replication and neutralization, but their quantitative relationship was unknown. Here we use mathematical models to quantitatively investigate viral survivability determined by antibody concentration and inocula size. We performed focus reduction assays for 49 seasonal influenza A/H3N2 viruses circulating during 2017-2019 against influenza antisera raised in ferrets, and find that the antibody consumption rates of individual reactions were either small or large, and this was strongly positively correlated with virus saturation. Regardless of antibody consumption rate, virus-antibody interactions always lead to antibody-induced bistable viral kinetics. As a result, at a specific interval of antibody concentration, small viral inocula are eliminated but not large virus inocula, which is triggered by saturated virus neutralization or antibody consumption. Our finding highlights virus-antibody interaction with different antigenic properties, thereby explaining commonly observed influenza re-infection and enhancing vaccine efficiency.

microbiology↗