Development and validation of a radiomics-based model for predicting osteoporosis in patients with lumbar compression fractures.

BACKGROUND: Osteoporosis, a metabolic bone disorder, markedly elevates fracture risks, with vertebral compression fractures being predominant. Antiosteoporotic treatments for patients with osteoporotic vertebral compression fractures (OVCF) lessen both the occurrence of subsequent fractures and associated pain. Thus, diagnosing osteoporosis in OVCF patients is vital. PURPOSE: The aim of this study was to develop a predictive radiographic model using T1 sequence MRI images to accurately determine whether patients with lumbar spine compression fractures also have osteoporosis. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Patients over 45 years of age diagnosed with a fresh lumbar compression fracture. OUTCOME MEASURES: Diagnostic accuracy of the model (area under the ROC curve). METHODS: The study retrospectively collected clinical and imaging data (MRI and DEXA) from hospitalized lumbar compression fracture patients (L1-L4) aged 45 years or older between January 2021 and June 2023. Using the pyradiomics package in Python, features from the lumbar compression fracture vertebral region of interest (ROI) were extracted. Downscaling of the extracted features was performed using the Mann-Whitney U test and the least absolute shrinkage selection operator (LASSO) algorithm. Subsequently, six machine learning models (Naive Bayes, Support Vector Machine [SVM], Decision Tree, Random Forest, Extreme Gradient Boosting [XGBoost], and Light Gradient Boosting Machine [LightGBM]) were employed to train and validate these features in predicting osteoporosis comorbidity in OVCF patients. RESULTS: A total of 128 participants, 79 in the osteoporotic group and 49 in the non-osteoporotic group, met the study's inclusion and exclusion criteria. From the T1 sequence MRI images, 1906 imaging features were extracted in both groups. Utilizing the Mann-Whitney U test, 365 radiologic features were selected out of the initial 1,906. Ultimately, the lasso algorithm identified 14 significant radiological features. These features, incorporated into six conventional machine learning algorithms, demonstrated successful prediction of osteoporosis in the validation set. The NaiveBayes model yielded an area under the receiver operating characteristic curve (AUC) of 0.84, sensitivity of 0.87, specificity of 0.70, and accuracy of 0.81. CONCLUSIONS: A NaiveBayes machine learning algorithm can predict osteoporosis in OVCF patients using t1-sequence MRI images of lumbar compression fractures. This approach aims to obviate the necessity for further osteoporosis assessments, diminish patient exposure to radiation, and bolster the clinical care of patients with OVCF.

Mitochondrial genome provides species-specific targets for the rapid detection of early invasive populations of Hylurgus ligniperda in China.

BACKGROUND: Hylurgus ligniperda, a major international forestry quarantine pest, was recently found to have invaded and posed a serious threat to the Pinus forests of the Jiaodong Peninsula in China. Continuous monitoring and vigilance of the early population is imperative, and rapid molecular detection technology is urgently needed. We focused on developing a single-gene-based species-specific PCR (SS-PCR) method. RESULTS: We sequenced and assembled the mitochondrial genome of H. ligniperda to identify suitable target genes. We identified three closely related species for detecting the specificity of SS-PCR through phylogenetic analysis based on 13 protein-coding genes (PCGs). Subsequently, we analyzed the evolution of 13 PCGs and selected four mitochondrial genes to represent slow-evolving gene (COI) and faster-evolving genes (e.g. ND2, ND4, and ND5), respectively. We developed four species-specific primers targeting COI, ND2, ND4, and ND5 to rapidly identify H. ligniperda. The results showed that the four species-specific primers exhibited excellent specificity and sensitivity in the PCR assays, with consistent performance across a broader range of species. This method demonstrates the ability to identify beetles promptly, even during their larval stage. The entire detection process can be completed within 2-3 h. CONCLUSIONS: This method is suitable for large-scale species detection in laboratory settings. Moreover, the selection of target genes in the SS-PCR method is not affected by the evolutionary rate. SS-PCR can be widely implemented at port and forestry workstations, significantly enhancing early management strategies and quarantine measures against H. ligniperda. This approach will help prevent the spread of the pest and effectively preserve the resources of Chinese pine forests.

Immune-privileged tissues formed from immunologically cloaked mouse embryonic stem cells survive long term in allogeneic hosts.

The immunogenicity of transplanted allogeneic cells and tissues is a major hurdle to the advancement of cell therapies. Here we show that the overexpression of eight immunomodulatory transgenes (Pdl1, Cd200, Cd47, H2-M3, Fasl, Serpinb9, Ccl21 and Mfge8) in mouse embryonic stem cells (mESCs) is sufficient to immunologically 'cloak' the cells as well as tissues derived from them, allowing their survival for months in outbred and allogeneic inbred recipients. Overexpression of the human orthologues of these genes in human ESCs abolished the activation of allogeneic human peripheral blood mononuclear cells and their inflammatory responses. Moreover, by using the previously reported FailSafe transgene system, which transcriptionally links a gene essential for cell division with an inducible and cell-proliferation-dependent kill switch, we generated cloaked tissues from mESCs that served as immune-privileged subcutaneous sites that protected uncloaked allogeneic and xenogeneic cells from rejection in immune-competent hosts. The combination of cloaking and FailSafe technologies may allow for the generation of safe and allogeneically accepted cell lines and off-the-shelf cell products.

Cell-based passive immunization for protection against SARS-CoV-2 infection.

BACKGROUND: Immunologically impaired individuals respond poorly to vaccines, highlighting the need for additional strategies to protect these vulnerable populations from COVID-19. While monoclonal antibodies (mAbs) have emerged as promising tools to manage infectious diseases, the transient lifespan of neutralizing mAbs in patients limits their ability to confer lasting, passive prophylaxis from SARS-CoV-2. Here, we attempted to solve this problem by combining cell and mAb engineering in a way that provides durable immune protection against viral infection using safe and universal cell therapy. METHODS: Mouse embryonic stem cells equipped with our FailSafe™ and induced allogeneic cell tolerance technologies were engineered to express factors that potently neutralize SARS-CoV-2, which we call 'neutralizing biologics' (nBios). We subcutaneously transplanted the transgenic cells into mice and longitudinally assessed the ability of the cells to deliver nBios into circulation. To do so, we quantified plasma nBio concentrations and SARS-CoV-2 neutralizing activity over time in transplant recipients. Finally, using similar cell engineering strategies, we genetically modified FailSafe™ human-induced pluripotent stem cells to express SARS-CoV-2 nBios. RESULTS: Transgenic mouse embryonic stem cells engineered for safety and allogeneic-acceptance can secrete functional and potent SARS-CoV-2 nBios. As a dormant, subcutaneous tissue, the transgenic cells and their differentiated derivatives long-term deliver a supply of protective nBio titers in vivo. Moving toward clinical relevance, we also show that human-induced pluripotent stem cells, similarly engineered for safety, can secrete highly potent nBios. CONCLUSIONS: Together, these findings show the promise and potential of using 'off-the-shelf' cell products that secrete neutralizing antibodies for sustained protective immunity against current and future viral pathogens of public health significance.

Rapid assay using recombinase polymerase amplification and lateral flow dipstick for identifying Agrilus mali (Coleoptera: Buprestidae), a serious wood-boring beetle of the western Tianshan Mountains in China.

Agrilus mali stands as a significant wood-boring pest prevalent in Northeast Asia. Identifying this pest beetle is often hindered by insufficient efficient, rapid, on-site discrimination methods beyond examining adult morphological features. As a result, an urgent need arises for developing and implementing a rapid and accurate molecular technique to distinguish and manage the beetle. This study presents a straightforward, swift, highly specific, and sensitive method built upon recombinase polymerase amplification combined with a lateral flow dipstick (RPA-LFD). This method demonstrates the capability to promptly identify the beetle, even during its larval stage. RPA primers and probes were designed using the internal transcribed spacer 1 region. Through probe optimization, false-positive signals were successfully eliminated, with an accompanying discussion on the underlying causes of such signals. The RPA-LFD assays exhibited remarkable specificity and sensitivity, requiring as little as 10-3 ng of purified DNA. Furthermore, the extraction of crude DNA was achieved through immersion in sterile distilled water, thus streamlining the assay process. Achievable at temperatures ranging from 30 to 50 °C, the RPA-LFD assay can be executed manually without specialized equipment. By merging the RPA-LFD assay with DNA coarse extraction, A. mali can be detected within just 30 min. This current study effectively demonstrates the immense potential of RPA-LFD in quarantine and pest management. Additionally, it presents a universal technique for the rapid on-site diagnosis of insects, showcasing the wide applicability of this method.

Soluble CX3CL1-expressing retinal pigment epithelium cells protect rod photoreceptors in a mouse model of retinitis pigmentosa.

BACKGROUND: Retinitis pigmentosa (RP) is an inherited retinal disease that results in photoreceptor degeneration, leading to severe vision loss or blindness. Due to its genetic heterogeneity, developing a new gene therapy to correct every genetic mutation contributing to its progression is infeasible. Photoreceptor transplantation can be harnessed to restore vision; however, this approach is limited by poor cell survival and synaptic integration into the neural retina. Thus, we developed a combined cell and gene therapy that is expected to protect photoreceptors in most, if not all, cases of RP. METHODS: Human embryonic stem cells (hESCs) modified with our FailSafe™ system were genetically engineered to overexpress sCX3CL1, an inhibitor of microglia activation that has been shown to preserve photoreceptor survival and function in mouse models of RP, independent of the genetic cause. These cells were differentiated into human retinal pigment epithelium (hRPE) cells and used as therapeutic cells due to their longevity and safety, both of which have been demonstrated in preclinical and clinical studies. Transgenic hRPE were delivered into the subretinal space of immunodeficient mice and the rd10 mouse model of RP to evaluate donor cell survival and retention of transgene expression. The outer nuclear layer was quantified to assess photoreceptor protection. RESULTS: Transgenic FailSafe™ hRPE (FS-hRPE) cells can survive for at least four months in the retina of immunodeficient mice and retain transgene expression. However, these cells do not persist beyond two weeks post-injection in the retina of immunocompetent rd10 recipients, despite Cyclosporine A treatment. Nevertheless, sCX3CL1-expressing FailSafe™ hRPE cells prevented photoreceptor degeneration in a local acting manner during the duration of their presence in the subretinal space. CONCLUSIONS: Transgenic hESCs differentiate into hRPE cells and retain sCX3CL1 transgene expression both in vitro and in vivo. Moreover, hRPE cells delivered to the subretinal space of rd10 mice prevented photoreceptor degeneration in a local-acting manner, suggesting that this approach could have applications for preserving photoreceptors in specific subregions of the retina, such as the macula. Overall, our study not only reveals the potential of a combined cell and gene therapy for the treatment of RP, but also the possibility of using hRPE cells to deliver therapeutic biologics in situ to treat diseases over long-term.

Indium Cyanamide for Industrial-Grade CO2 Electroreduction to Formic Acid.

Developing industrial-grade electroreduction of CO2 to produce formate (HCOO-)/formic acid (HCOOH) depends on highly active electrocatalysts. However, structural changes due to the inevitable self-reduction of catalysts result in severe long-term stability issues at industrial-grade current density. Herein, linear cyanamide anion ([NCN]2-)-constructed indium cyanamide nanoparticles (InNCN) were investigated for CO2 reduction to HCOO- with a Faradaic efficiency of up to 96% under a partial current density (jformate) of 250 mA cm-2. Bulk electrolysis at a jformate of 400 mA cm-2 requires only -0.72 VRHE applied potential with iR correction. It also achieves continuous production of pure HCOOH at ∼125 mA cm-2 for 160 h. The excellent activity and stability of InNCN are attributed to its unique structural features, including strongly σ-donating [NCN]2- ligands, the potential structural transformation of [N═C═N]2- and [N≡C-N]2-, and the open framework structure. This study affirms metal cyanamides as promising novel materials for electrocatalytic CO2 reduction, broadening the variety of CO2 reduction catalysts and the understanding of structure-activity relationships.

Daily loneliness and social media use: The role of fear of missing out.

This study explored the effect of daily loneliness on social media use and the mediating role of fear of missing out (FoMO). A total of 106 college students participated in a 2-week experience sampling study, yielding 1194 data points. The results showed that daily loneliness predicted social media use via FoMO.

Role of lncRNA MAGI2-AS3 in lipopolysaccharide-induced nucleus pulposus cells injury by regulating miR-374b-5p/interleukin-10 axis.

BACKGROUND: Intervertebral disc degeneration (IDD) is a pathological process that occurs during the natural aging of intervertebral discs. Accumulating evidence suggests that noncoding RNAs (ncRNAs), including microRNAs and long ncRNAs (lncRNAs), participate in the pathogenesis and development of IDD. Herein, we examined the role of lncRNA MAGI2-AS3 in the pathogenic mechanism of IDD. MATERIAL AND METHODS: To develop an IDD in vitro model, we treated human nucleus pulposus (NP) cells with lipopolysaccharide (LPS). Aberrant levels of lncRNA MAGI2-AS3, miR-374b-5p, interleukin (IL)-10 and extracellular matrix (ECM)-related proteins in NP cells were examined using reverse transcription-quantitative PCR and western blot analysis. LPS-induced NP cell injury and inflammatory response were confirmed using the MTT assay, flow cytometry, Caspase3 activity, and enzyme-linked immunosorbent assay. Dual-luciferase reporter assay and rescue experiments were performed to confirm targets between lncRNA MAGI2-AS3 and miR-374b-5p or miR-374b-5p and IL-10. RESULTS: LPS-induced NP cells exhibited low levels of lncRNA MAGI2-AS3 and IL-10 expression, along with high miR-374b-5p expression. miR-374b-5p was a target of lncRNA MAGI2-AS3 and IL-10. LncRNA MAGI2-AS3 ameliorated injury, inflammatory response, and ECM degradation in LPS-treated NP cells by downregulating miR-374b-5p to upregulate IL-10 expression. CONCLUSIONS: LncRNA MAGI2-AS3 increased IL-10 expression levels by sponging miR-374b-5p, which, in turn, alleviated LPS-triggered decreased NP cell proliferation and increased apoptosis, inflammatory response, and ECM degradation. Therefore, lncRNA MAGI2-AS3 may be a potential therapeutic target for IDD.

General synthesis of CoCeMOx trimetallic oxides via a cation exchange reaction for the oxygen evolution reaction.

Cobalt-based spinel oxides are considered potential candidates for the oxygen evolution reaction (OER) due to their abundant valence changes and promising electrochemical activity, but their low intrinsic activity hinders their practical applications. Herein, we synthesize a series of CoCeMOx (M = Zn, Ni, Ru, Er, Mg, Mn, Sn) derived from CoCeM coordination-driven self-assembled aggregates (CDSAAs) using a general ion exchange and subsequent calcination method. Interestingly, CoCeMOx exhibit different morphologies from porous nanospheres, particle-stacked nanospheres, to hollow nanospheres as the third metal element is altered. Markedly, CoCeZnOx porous nanospheres (PNs) exhibit the best OER performance. The XPS results reveal that the existence of CeO2 and Zn2+ ions significantly increased the Co2+/Co3+ ratio and the content of oxygen vacancies in Co3O4. Furthermore, Co2+ can be used as highly reactive sites to form CoOOH and the high content of oxygen vacancies can optimize the oxygen-containing intermediate adsorption energy, both of which can effectively improve the OER performance. Therefore, well-designed CoCeZnOx PNs demonstrate high OER activity with a lower overpotential (η = 333 mV) than that of commercial RuO2 (344 mV) in 10 mA cm-2, a Tafel slope of 98 mV dec-1, and a long-term durability of 45 h. This work may provide some inspiration for the design of trimetallic oxide nanomaterials.

A lesion extending three or more slices as a predictor of progressive infarction in anterior circulation small subcortical infarction.

Progressive infarction (PI) is common in small subcortical infarction and may lead to a poor outcome. The purpose of our study is to identify neuroimaging predictors for PI. From April 2017 to December 2020, we enrolled 86 patients with an anterior circulation subcortical infarction within 48 h after onset. Progressive infarction was defined by an increase of ≥ one point in motor power or ≥ two points in the total National Institute of Health Stroke Scale score within 7 days after admission and further confirmed by diffusion-weighted imaging (DWI). To identify predictors, demographic characteristics, clinical information, laboratory date, and neuroimaging characteristics were evaluated. The infarct size and infarct slice number were measured by DWI. We found that thirty-one patients (36%) had PI. In a univariate analysis, the patients with PI had higher levels of triglyceride, lower levels of blood urea nitrogen and prothrombin time, and a higher frequency of infarct slice number ≥ three compared to the patients without PI. After logistic regression stepwise adjustment for all considered relevant confounders, infarct slice number ≥ three slices proved to be independently associated with PI (OR = 4.781, 95% CI 1.677-13.627; OR = 4.867, 95% CI 1.6-14.864; OR = 3.584, 95% CI 1.034-12.420). Our study showed that a lesion extending ≥ three slices on DWI is an independent predictor for progressive infarction in patients with anterior circulation small subcortical infarction.

The complete mitochondrial genome of Platygaster robiniae (Hymenoptera: Platygastridae): A novel tRNA secondary structure, gene rearrangements and phylogenetic implications.

Platygaster robiniae is economically important as a highly specific parasitoid of the invasive pest Obolodiplosis robiniae which was introduced into the Euro-Asia region in the last decade. Despite being a critical and specific parasitoid of the invasive pest O. robiniae and its use as an effective biocontrol agent, the absence of sequence information from P. robiniae have limited its genetic applications for pest management in forests. Mitochondrial (mt) genomes generally contain abundant nucleotide information and thus are helpful for understanding species history. Here, we sequenced the complete mt genome of P. robiniae using next generation sequencing, and annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 702 bp noncoding region. Comparative analysis indicated that this mt genome has a normal A + T content and codons use, however possessed both the expected and unique rearrangements. Ten tRNAs at four gene blocks COII-ATP8, COIII-ND3, ND3-ND5 and the A + T-rich region-ND2 were rearranged, including gene shuffles, transpositions and inversions. Notably, two genes tRNA Ser(UCN) and tRNA Leu(CUN) had undergone long-range inversions, which is the first record of this rearrangement type in the superfamily Platygastroidea. The D-loops of both tRNA Ile and tRNA Leu(CUN) were absent from the tRNA secondary structure, which has not been reported from hymenopteran previously. Phylogenetic analysis based with the maximum likelihood and Bayesian methods showed that P. robiniae grouped with other species of Platygastridae, and that the superfamily Platygastridea is sister to the other Proctotrupomorpha superfamilies. Our tree strongly supports the monophyly of the five superfamilies of Proctotrupomorpha. This study discovered some unique characters of P. robiniae, and contributes to our understanding of genome rearrangements in the order Hymenoptera.

Population Genetics Reveals That the Western Tianshan Mountains Populations of Agrilus mali (Coleoptera: Buprestidae) May Have Not been Recently Introduced.

Agrilus mali Matsumura is a wood-boring beetle that aggressively attacks species of the genus Malus, that has recently caused serious damage to the wild apple tree M. sieversii (Lebed.) in the western Tianshan Mountains in Xinjiang. It was first detected there in the early 1990s and spread rapidly, being thus considered a regional invasive pest. To explore the possible outbreak mechanism of the local population and characterize the genetic differentiation of A. mali across different regions of China, we used three mitochondrial genes (COI, COII, and CytB) to investigate the genetic diversity and genetic structure of 17 A. mali populations containing 205 individuals collected from five Chinese provinces. Among them, nine populations were from the western Tianshan Mountains. Ultimately, of the 136 pairwise F st comparisons, 99 showed high genetic differentiation among overall populations, and Tianshan populations exhibited significant differentiation with most of the non-Tianshan populations. Furthermore, A. mali populations represented relatively abundant haplotypes (54 haplotypes). Nine populations from the Tianshan Mountains showed 32 haplotypes (26 of which were unique), displaying relatively high genetic diversity. Additionally, the Mantel test revealed population genetic differentiation among either overall populations or the Tianshan Mountains populations, likely caused by geographical isolation. Phylogenic relationships showed that all populations clustered into three clades, and Tianshan Mountains populations, including CY, occupied one of the three clades. These results suggest that A. mali in the western Tianshan region has possibly been present in the area for a long period, and may not have been introduced recently. Highly frequent gene flows within Tianshan populations are possibly caused by human activities and may enhance the adaptability of A. mali along the western Tianshan Mountains, leading to periodic outbreaks. These findings enhance our understanding of jewel beetle population genetics and provide valuable information for pest management.

Construction of Heterostructured Sn/TiO2 /Si Photocathode for Efficient Photoelectrochemical CO2 Reduction.

Using renewable energy to convert CO2 into liquid products, as a sustainable way to produce fuels and chemicals, has attracted intense attention. Herein, a novel heterostructured photocathode composed of Si wafer, TiO2 layer, and Sn metal particles has been successfully fabricated by combining of a facile hydrothermal and electrodeposition method. The obtained Sn/TiO2 /Si photocathode shows enhanced light absorption performance by the surface plasmon resonance effect of Sn metal. Especially, the Sn/TiO2 /Si photocathode together with rich oxygen vacancy defects jointly promote photoelectrochemical CO2 reduction, harvesting a high faradaic efficiency of HCOOH and a desirable average current density (-4.72 mA cm-2 ) at -1.0 V vs. reversible hydrogen electrode. Significantly, the photocathode Sn/TiO2 /Si also shows good stability due to the design of protecting layer TiO2 . This study provides a facile strategy of constructing an efficient photocathode to improve the light absorption performance and the electron transfer efficiency, exhibiting great potential in the CO2 reduction.

Common and discrete mechanisms underlying chronic pain and itch: peripheral and central sensitization.

Normally, an obvious antagonism exists between pain and itch. In normal conditions, painful stimuli suppress itch sensation, whereas pain killers often generate itch. Although pain and itch are mediated by separate pathways under normal conditions, most chemicals are not highly specific to one sensation in chronic pathologic conditions. Notably, in patients with neuropathic pain, histamine primarily induces pain rather than itch, while in patients with atopic dermatitis, bradykinin triggers itch rather than pain. Accordingly, repetitive scratching even enhances itch sensation in chronic itch conditions. Physicians often prescribe pain relievers to patients with chronic itch, suggesting common mechanisms underlying chronic pain and itch, especially peripheral and central sensitization. Rather than separating itch and pain, studies should investigate chronic itch and pain including neuropathic and inflammatory conditions. Here, we reviewed chronic sensitization leading to chronic pain and itch at both peripheral and central levels. Studies investigating the connection between pain and itch facilitate the development of new therapeutics against both chronic dysesthesias based on the underlying pathophysiology.

[Correlation of B-type Natriuretic Peptide Level with Hemodynamic Parameters and Inflammatory Cytokines in Patients with Gram-negative Sepsis].

Objective To study the correlation of B-type natriuretic peptide(BNP)level with hemodynamic parameters and inflammatory cytokines in patients with Gram-negative sepsis,and further determine the main factors for the significant increase of BNP level. Methods The prospective study method was applied,and septic patients infected with Gram-negative bacteria from May 2017 to October 2019 were enrolled.The patients were divided into the BNP<2400 ng/L group and the BNP≥2400 ng/L group by taking the average value of BNP as the dividing point.The independent predictors of BNP≥2400 ng/L were analyzed by Logistic regression.Pearson correlation analysis was used to analyze the correlation between BNP and various indicators. Results A total of 106 patients with Gram-negative sepsis were included,among which 60 cases present with higher serum BNP levels than the average of(2398.45 ± 421.45)ng/L.Thus BNP≥2400 ng/L was considered as a significantly increased BNP level.Multiple logistic regression analysis showed that cardiac index(CI)[odds ratio (OR)=0.428,95% confidence interval (95%CI)=0.743-0.965,P=0.011],left ventricular ejection fraction(LVEF) (OR=0.394,95%CI=0.182-0.549,P=0.013),lactic acid (OR=1.983,95%CI=1.264-3.420,P=0.023),endotoxin (OR=6.146,95%CI=4.091-8.226,P=0.001),procalcitonin(PCT) (OR=6.513,95%CI=4.365-8.210,P=0.005) and cardiac troponin I(cTnI) (OR=1.144,95%CI=1.001-2.150,P=0.047) were independent predictors of BNP≥2400 ng/L in patients with Gram-negative sepsis.Pearson correlation analysis showed that BNP was negatively correlated with CI(R=-0.514,P<0.001)and LVEF (R=-0.552,P<0.001),whereas positively correlated with lactic acid (R=0.265,P=0.032),cTnI (R=0.204, P=0.036),PCT(R=0.801,P<0.001),and endotoxin(R=0.765,P<0.001). Conclusions In septic patients with Gram-negative bacterial infection,LVEF,CI,lactic acid,cTnI,endotoxin and PCT are all independent risk factors for the significant increase of BNP,and endotoxin and PCT were more significantly correlated with BNP increase.Endotoxin and inflammatory reaction may be the more important stimulators of BNP increase in septic patients with Gram-negative bacterial infection.

Forward genetic screen in human podocytes identifies diphthamide biosynthesis genes as regulators of adhesion.

Podocyte function is tightly linked to the complex organization of its cytoskeleton and adhesion to the underlying glomerular basement membrane. Adhesion of cultured podocytes to a variety of substrates is reported to correlate with podocyte health. To identify novel genes that are important for podocyte function, we designed an in vitro genetic screen based on podocyte adhesion to plates coated with either fibronectin or soluble Fms-like tyrosine kinase-1 (sFLT1)/Fc. A genome-scale pooled RNA interference screen on immortalized human podocytes identified 77 genes that increased adhesion to fibronectin, 101 genes that increased adhesion to sFLT1/Fc, and 44 genes that increased adhesion to both substrates when knocked down. Multiple shRNAs against diphthamide biosynthesis protein 1-4 (DPH1-DPH4) were top hits for increased adhesion. Immortalized human podocyte cells stably expressing these hairpins displayed increased adhesion to both substrates. We then used CRISPR-Cas9 to generate podocyte knockout cells for DPH1, DPH2, or DPH3, which also displayed increased adhesion to both fibronectin and sFLT1/Fc, as well as a spreading defect. Finally, we showed that Drosophila nephrocyte-specific knockdown of Dph1, Dph2, and Dph4 resulted in altered nephrocyte function. In summary, we report here a novel high-throughput method to identify genes important for podocyte function. Given the central role of podocyte adhesion as a marker of podocyte health, these data are a rich source of candidate regulators of glomerular disease.

Targeting VE-PTP phosphatase protects the kidney from diabetic injury.

Diabetic nephropathy is a leading cause of end-stage kidney failure. Reduced angiopoietin-TIE2 receptor tyrosine kinase signaling in the vasculature leads to increased vascular permeability, inflammation, and endothelial cell loss and is associated with the development of diabetic complications. Here, we identified a mechanism to explain how TIE2 signaling is attenuated in diabetic animals. Expression of vascular endothelial protein tyrosine phosphatase VE-PTP (also known as PTPRB), which dephosphorylates TIE2, is robustly up-regulated in the renal microvasculature of diabetic rodents, thereby reducing TIE2 activity. Increased VE-PTP expression was dependent on hypoxia-inducible factor transcriptional activity in vivo. Genetic deletion of VE-PTP restored TIE2 activity independent of ligand availability and protected kidney structure and function in a mouse model of severe diabetic nephropathy. Mechanistically, inhibition of VE-PTP activated endothelial nitric oxide synthase and led to nuclear exclusion of the FOXO1 transcription factor, reducing expression of pro-inflammatory and pro-fibrotic gene targets. In sum, we identify inhibition of VE-PTP as a promising therapeutic target to protect the kidney from diabetic injury.

Transcription Factor 21 Is Required for Branching Morphogenesis and Regulates the Gdnf-Axis in Kidney Development.

BACKGROUND: The mammalian kidney develops through reciprocal inductive signals between the metanephric mesenchyme and ureteric bud. Transcription factor 21 (Tcf21) is highly expressed in the metanephric mesenchyme, including Six2-expressing cap mesenchyme and Foxd1-expressing stromal mesenchyme. Tcf21 knockout mice die in the perinatal period from severe renal hypodysplasia. In humans, Tcf21 mRNA levels are reduced in renal tissue from human fetuses with renal dysplasia. The molecular mechanisms underlying these renal defects are not yet known. METHODS: Using a variety of techniques to assess kidney development and gene expression, we compared the phenotypes of wild-type mice, mice with germline deletion of the Tcf21 gene, mice with stromal mesenchyme-specific Tcf21 deletion, and mice with cap mesenchyme-specific Tcf21 deletion. RESULTS: Germline deletion of Tcf21 leads to impaired ureteric bud branching and is accompanied by downregulated expression of Gdnf-Ret-Wnt11, a key pathway required for branching morphogenesis. Selective removal of Tcf21 from the renal stroma is also associated with attenuation of the Gdnf signaling axis and leads to a defect in ureteric bud branching, a paucity of collecting ducts, and a defect in urine concentration capacity. In contrast, deletion of Tcf21 from the cap mesenchyme leads to abnormal glomerulogenesis and massive proteinuria, but no downregulation of Gdnf-Ret-Wnt11 or obvious defect in branching. CONCLUSIONS: Our findings indicate that Tcf21 has distinct roles in the cap mesenchyme and stromal mesenchyme compartments during kidney development and suggest that Tcf21 regulates key molecular pathways required for branching morphogenesis.