CRB1-associated retinal degeneration is dependent on bacterial translocation from the gut.

The Crumbs homolog 1 (CRB1) gene is associated with retinal degeneration, most commonly Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP). Here, we demonstrate that murine retinas bearing the Rd8 mutation of Crb1 are characterized by the presence of intralesional bacteria. While normal CRB1 expression was enriched in the apical junctional complexes of retinal pigment epithelium and colonic enterocytes, Crb1 mutations dampened its expression at both sites. Consequent impairment of the outer blood retinal barrier and colonic intestinal epithelial barrier in Rd8 mice led to the translocation of intestinal bacteria from the lower gastrointestinal (GI) tract to the retina, resulting in secondary retinal degeneration. Either the depletion of bacteria systemically or the reintroduction of normal Crb1 expression colonically rescued Rd8-mutation-associated retinal degeneration without reversing the retinal barrier breach. Our data elucidate the pathogenesis of Crb1-mutation-associated retinal degenerations and suggest that antimicrobial agents have the potential to treat this devastating blinding disease.

Frequency and clinical significance of Herpes simplex virus type 1/2 reactivation in adult patients with mild to moderately severe community-acquired pneumonia: a multicentre cohort study.

PURPOSE: This study assessed the frequency, clinical significance, and risk factors for Herpes simplex virus (HSV) reactivation in immunocompetent patients with community-acquired pneumonia (CAP). METHODS: The study included adult CAP-patients who were enrolled in the CAPNETZ study between 2007 and 2017 and had a residual sputum sample available for analysis. In addition to routine diagnostics, sputum and blood samples were tested for HSV-1/2 using PCR. Demographics, comorbidities, and CRB-65 score were compared between HSV-positive and negative patients using Fisher exact or Mann Whitney test. Logistic regression analyses investigated the influence of HSV reactivation on a modified hospital recovery scale (HRS) until day 7, divided into 3 categories (no oxygen therapy, oxygen therapy, ICU admission or death). RESULTS: Among 245 patients, HSV-1 and HSV-2 were detected in 30 patients (12.2%, 95%CI 8.7-16.9) and 0 patients, respectively. All HSV-positive patients were hospitalized, had a CRB-65 severity score of 0-2 and survived the first 28 day. In the HSV-positive group, patients had a non-significantly higher median age (70.5 versus 66 years) and a higher rate of oncological comorbidities (16.7% versus 8.8%) compared to the HSV-negative group. Distribution of co-pathogens and outcome parameters did not significantly differ between both groups. In a multivariate logistic regression model, age (AOR 1.029, p = 0.012) and CRB-65 score (AOR 1.709, p = 0.048), but not HSV-1 as single or co-pathogen were independently associated with higher HRS. CONCLUSION: Our study suggests that HSV-1 reactivation is common in CAP but might not be associated with specific risk factors or a complicated disease course.

Genotype-phenotype associations in CRB1 bi-allelic patients: a novel mutation, a systematic review and meta-analysis.

PURPOSE: The goal of the study was to search for novel bi-allelic CRB1 mutations, and then to analyze the CRB1 literature at the genotypic and phenotypic levels. APPROACH: We screened various variables such as the CRB1 mutation types, domains, exons, and genotypes and their relation with specific ocular phenotypes. An emphasis was given to the bi-allelic missense and nonsense mutations because of their high prevalence compared to other mutation types. Finally, we quantified the effect of various non-modifiable factors over the best-corrected visual acuity oculus uterque (BCVA OU) using multivariate linear regression models and identified genetic interactions. RESULTS: A novel bi-allelic missense in the exon 9 of CRB1; c.2936G > A; p.(Gly979Asp) was found to be associated with rod-cone dystrophy (RCD). CRB1 mutation type, exons, domains, and genotype distribution varied significantly according to fundus characteristics, such as peripheral pigmentation and condition, optic disc, vessels, macular condition, and pigmentation (P < 0.05). Of the 154 articles retrieved from PubMed, 96 studies with 439 bi-allelic CRB1 patients were included. Missense mutations were significantly associated with an absence of macular pigments, pale optic disc, and periphery pigmentation, resulting in a higher risk of RCD (P < 0.05). In contrast, homozygous nonsense mutations were associated with macular pigments, periphery pigments, and a high risk of LCA (P < 0.05) and increased BCVA OU levels. We found that age, mutation types, and inherited retinal diseases were critical determinants of BCVA OU as they significantly increased it by 33% 26%, and 38%, respectively (P < 0.05). Loss of function alleles additively increased the risk of LCA, with nonsense having a more profound effect than indels. Finally, our analysis showed that p.(Cys948Tyr) and p.(Lys801Ter) and p.(Lys801Ter); p.(Cys896Ter) might interact to modify BCVA OU levels. CONCLUSION: This meta-analysis updated the literature and identified genotype-phenotype associations in bi-allelic CRB1 patients.

Identification and characterization of Crumbs polarity complex proteins in Caenorhabditis elegans.

Crumbs proteins are evolutionarily conserved transmembrane proteins with essential roles in promoting the formation of the apical domain in epithelial cells. The short intracellular tail of Crumbs proteins are known to interact with several proteins, including the scaffolding protein PALS1 (protein associated with LIN7, Stardust in Drosophila). PALS1 in turn binds to a second scaffolding protein PATJ (PALS1-associated tight junction protein) to form the core Crumbs/PALS1/PATJ complex. While essential roles in epithelial organization have been shown for Crumbs proteins in Drosophila and mammalian systems, the three Caenorhabditis elegans crumbs genes are dispensable for epithelial polarization and development. Here, we investigated the presence and function of PALS1 and PATJ orthologs in C. elegans. We identified MAGU-2 as the C. elegans ortholog of PALS1 and show that MAGU-2 interacts with all three Crumbs proteins and localizes to the apical membrane domain of intestinal epithelial cells in a Crumbs-dependent fashion. Similar to crumbs mutants, magu-2 deletion showed no epithelial polarity defects. We also identified MPZ-1 as a candidate ortholog of PATJ based on the physical interaction with MAGU-2 and sequence similarity with PATJ proteins. However, MPZ-1 is not broadly expressed in epithelial tissues and, therefore, not likely a core component of the C. elegans Crumbs complex. Finally, we show overexpression of the Crumbs proteins EAT-20 or CRB-3 can lead to apical membrane expansion in the intestine. Our results shed light on the composition of the C. elegans Crumbs complex and indicate that the role of Crumbs proteins in promoting apical domain formation is conserved.

Identification of key variants correlated with susceptibility of primary osteoporosis in the Chinese Han group.

BACKGROUND: Primary osteoporosis is a systemic skeletal disease characterized by reduced bone mass and vulnerability to fractures. The genetics of osteoporosis in the Chinese population remain unclear, which hinders the prevention and treatment of osteoporosis in China. This study aimed to explore the susceptibility genes and the roles played by their variants in osteoporosis. METHODS: Blood samples were collected from 45 osteoporosis patients and 30 healthy individuals, and genome-wide association study was performed on array data. The expression levels of the candidate gene in different genotypes were further determined by using quantitative real-time PCR. Moreover, the differentiation capacity of bone marrow mesenchymal stem cells under different genotypes from osteoporosis patients was investigated. RESULTS: The most significant variant rs1891632 located in the upstream (918 bp) region of CRB2, which could down-regulate the expression levels of CRB2 in genotype-tissue expression database and played an essential role in the regulation of osteoblastic and osteoclastic differentiation during skeletal development. Another significant variant rs1061657 located within the 3'UTR region of TBX3 gene. We found that the mRNA levels of TBX3 decreased in the bMSCs of old osteoporosis patients. Interestingly, osteoblast differentiation capacity and TBX3 mRNA levels were similar between the young healthy individuals carrying derived and ancestral allele of rs1061657, whereas the differentiation capacity and TBX3 mRNA levels dramatically declined in elderly patients with osteoporosis. CONCLUSIONS: The variant rs1061657 might affect the osteogenesis of bMSCs in an age-dependent manner and that TBX3 may be a key susceptibility gene for primary osteoporosis. In conclusion, CRB2 and TBX3 may influence the development of osteoporosis; additionally, rs1891632 and rs1061657, as the key variants first reported to be associated with primary osteoporosis, may potentially contribute to predicting the risk of osteoporosis (especially for older individuals) and may serve as therapeutic targets.

Six new cases of CRB2-related syndrome and a review of clinical findings in 28 reported patients.

The Crumbs homolog-2 (CRB2)-related syndrome (CRBS-RS) is a rarely encountered condition initially described as a triad comprising ventriculomegaly, Finnish nephrosis, and elevated alpha-fetoprotein levels in maternal serum and amniotic fluid. CRB2-related syndrome is caused by biallelic, pathogenic variants in the CRB2 gene. Recent reports of CRB2-RS have highlighted renal disease with persistent proteinuria and steroid-resistant nephrotic syndrome (SRNS). We report six new and review 28 reported patients with pathogenic variants in CRB2. We compare clinical features and variant information in CRB2 in patients with CRB2-RS and in those with isolated renal disease. The kidneys were the most frequently involved body system and 11 patients had only renal manifestations with SRNS or nephrotic syndrome. Central nervous system involvement was the next most common manifestation, followed by cardiac findings that included Scimitar syndrome. There was a significant clustering of pathogenic variants for CRB2-RS in exons 8 and 10, whereas pathogenic variants in exons 12 and 13 were associated with isolated renal disease. Further information is needed to determine optimal management but monitoring for renal and ocular complications should be considered.

Novel CRB1 pathogenic variant in Chuuk families with Leber congenital amaurosis.

The purpose of this article is to determine the cause of Leber congenital amaurosis (LCA) in Chuuk state, Federated States of Micronesia (FSM). In this prospective observational case series, five patients with early-onset vision loss were examined in Chuuk state, FSM, during an ocular genetics visit to study the elevated incidence of microphthalmia. Because of their low vision these patients were incorrectly assumed to have microphthalmia. A complete ophthalmological exam established a clinical diagnosis of LCA. Candidate gene exons were sequenced with a targeted retinal dystrophy panel. Five subjects in three related families were diagnosed with LCA. All five were from Tonoas Island, within the Chuuk Lagoon, with ages ranging from 6 months to 16 years. DNA sequencing of affected individuals revealed a homozygous CRB1 NM_201253.3:c.3134del pathogenic variant, which was heterozygous in their parents. CRB1 genotypes were confirmed by a PCR restriction assay. We report identification of a founder pathogenic variant in CRB1 responsible for autosomal recessive LCA in this isolated community. This discovery will lead to appropriate recurrence risk counseling.

A novel pathogenic CRB1 variant presenting as Leber Congenital Amaurosis 8 and evaluation of gene editing feasibility.

INTRODUCTION: Leber Congenital Amaurosis (LCA) is an inherited retinal disease that presents in infancy with severely decreased vision, nystagmus, and extinguished electroretinography findings. LCA8 is linked to variants in the Crumbs homolog 1 (CRB1) gene. CASE DESCRIPTION: We report a novel CRB1 variant in a 14-year-old male presenting with nystagmus, worsening vision, and inability to fixate on toys in his infancy. Color fundus photography revealed nummular pigments in the macula and periphery. Imaging studies revealed thickened retina on standard domain optical coherence tomography and widespread atrophy of the retinal pigment epithelium on autofluorescence. Full-field electroretinography revealed extinguished scotopic and significantly reduced photopic responses. Genetic testing demonstrated a novel homozygous variant, c.3057 T > A; p.(Tyr1019Ter), in the CRB1 gene. This variant is not currently amenable to base editing, however, in silico analysis revealed several potential prime editing strategies for correction. CONCLUSION: This case presentation is consistent with LCA8, suggesting pathogenicity of this novel variant and expanding our knowledge of disease-causing CRB1 variants.

Analysis of CRB1 Pathogenic Variants Correctable with CRISPR Base and Prime Editing.

The mouse and human retina contain three major Crumbs homologue-1 (CRB1) isoforms. CRB1-A and CRB1-B have cell-type-specific expression patterns making the choice of gene augmentation strategy unclear. Gene editing may be a viable alternative for the amelioration of CRB1-associated retinal degenerations. To assess the prevalence and spectrum of CRB1-associated pathogenic variants amenable to base and prime editing, we carried out an analysis of the Leiden Open Variation Database. Editable variants accounted for 54.5% for base editing and 99.8% for prime editing of all CRB1 pathogenic variants in the Leiden Open Variation Database. The 10 most common editable pathogenic variants for CRB1 accounted for 34.95% of all pathogenic variants, with the c.2843G>A, p.(Cys948Tyr) being the most common editable CRB1 variant. These findings outline the next step toward developing base and prime editing therapeutics as an alternative to gene augmentation for the amelioration of CRB1-associated retinal degenerations.

Generation of CRB1 RP Patient-Derived iPSCs and a CRISPR/Cas9-Mediated Homology-Directed Repair Strategy for the CRB1 c.2480G>T Mutation.

Mutations in the Crumbs-homologue-1 (CRB1) gene lead to a spectrum of severe inherited retinal diseases, including retinitis pigmentosa (RP). The establishment of a genotype-phenotype correlation in CRB1 patients has been difficult due to the substantial variability and phenotypic overlap between CRB1-associated diseases. This phenotypic modulation may be due to several factors, including genetic modifiers, deep intronic mutations, isoform diversity, and copy number variations. Induced pluripotent stem cell (iPSC)-derived patient retinal organoids are novel tools that can provide sensitive, quantitative, and scalable phenotypic assays. CRB1 RP patient iPSC-derived retinal organoids have shown reproducible phenotypes compared to healthy retinal organoids. However, having genetically defined iPSC isogenic controls that take into account potential phenotypic modulation is crucial. In this study, we generated iPSC from an early-onset CRB1 patient and developed a correction strategy for the c.2480G>T, p.(Gly827Val) CRB1 mutation using CRISPR/Cas9-mediated homology-directed repair.

A Novel Mouse Model of Idiopathic Nephrotic Syndrome Induced by Immunization with the Podocyte Protein Crb2.

BACKGROUND: The cause of podocyte injury in idiopathic nephrotic syndrome (INS) remains unknown. Although recent evidence points to the role of B cells and autoimmunity, the lack of animal models mediated by autoimmunity limits further research. We aimed to establish a mouse model mimicking human INS by immunizing mice with Crb2, a transmembrane protein expressed at the podocyte foot process. METHODS: C3H/HeN mice were immunized with the recombinant extracellular domain of mouse Crb2. Serum anti-Crb2 antibody, urine protein-to-creatinine ratio, and kidney histology were studied. For signaling studies, a Crb2-expressing mouse podocyte line was incubated with anti-Crb2 antibody. RESULTS: Serum anti-Crb2 autoantibodies and significant proteinuria were detected 4 weeks after the first immunization. The proteinuria reached nephrotic range at 9-13 weeks and persisted up to 29 weeks. Initial kidney histology resembled minimal change disease in humans, and immunofluorescence staining showed delicate punctate IgG staining in the glomerulus, which colocalized with Crb2 at the podocyte foot process. A subset of mice developed features resembling FSGS after 18 weeks. In glomeruli of immunized mice and in Crb2-expressing podocytes incubated with anti-Crb2 antibody, phosphorylation of ezrin, which connects Crb2 to the cytoskeleton, increased, accompanied by altered Crb2 localization and actin distribution. CONCLUSION: The results highlight the causative role of anti-Crb2 autoantibody in podocyte injury in mice. Crb2 immunization could be a useful model to study the immunologic pathogenesis of human INS, and may support the role of autoimmunity against podocyte proteins in INS.

Comparison of Prognostic Scores for Patients with COVID-19 Presenting with Dyspnea in the Emergency Department.

BACKGROUND: Easy-to-use bedside risk assessment is crucial for patients with COVID-19 in the overcrowded emergency department (ED). OBJECTIVE: The aim of this study was to explore the prognostic ability of ratio of percutaneous oxygen saturation (SpO2) to fraction of inspired oxygen (FiO2) (S/F); ratio of SpO2/FiO2 to respiratory rate (ROX); National Early Warning Score (NEWS); quick Sequential Organ Failure Assessment (qSOFA); and confusion, respiratory rate, blood pressure, and age ≥ 65 years (CRB-65) in patients with COVID-19 presenting with dyspnea to the ED. METHODS: In this retrospective observational study, clinical and demographic details of patients with COVID-19 were obtained at ED admission. S/F, ROX, NEWS, CRB-65, and qSOFA scores were calculated at the time of ED arrival. Accuracy of these five indices to predict the need for invasive mechanical ventilation (IMV) within 48 h, intensive care unit (ICU) admission, and early (7-day) mortality were determined using receiver operating characteristic curves. RESULTS: A total of 375 patients were included in this study. Fifty patients (13.3%) required IMV within 48 h and 58 patients (15.5%) were transferred to the ICU. Seven-day mortality was 6.7% and 28-day mortality was 18.1%. Among all five scores determined from patient data on ED admission, ROX, S/F, and NEWS presented greater discriminatory performance than CRB-65 and qSOFA in predicting IMV within 48 h, ICU admission, and early mortality. CONCLUSIONS: Emergency physicians can effectively use S/F, ROX, and NEWS scores for rapid risk stratification of patients with COVID-19 infection. Moreover, from the perspective of simplicity and ease of calculation, we recommend the use of the S/F ratio.

Foveal Hypoplasia in CRB1-Related Retinopathies.

The CRB1 gene plays a role in retinal development and its maintenance. When disrupted, it gives a range of phenotypes such as early-onset severe retinal dystrophy/Leber congenital amaurosis (EOSRD/LCA), retinitis pigmentosa (RP), cone-rod dystrophy (CORD) and macular dystrophy (MD). Studies in CRB1 retinopathies have shown thickening and coarse lamination of retinal layers resembling an immature retina. Its role in foveal development has not yet been described; however, this retrospective study is the first to report foveal hypoplasia (FH) presence in a CRB1-related retinopathy cohort. Patients with pathogenic biallelic CRB1 variants from Moorfields Eye Hospital, London, UK, were collected. Demographic, clinical data and SD-OCT analyses with FH structural grading were performed. A total of 15 (48%) patients had EOSRD/LCA, 11 (35%) MD, 3 (9%) CORD and 2 (6%) RP. FH was observed in 20 (65%; CI: 0.47-0.79) patients, all of whom were grade 1. A significant difference in BCVA between patients with FH and without was found (p = 0.014). BCVA continued to worsen over time in both groups (p < 0.001), irrespective of FH. This study reports FH in a CRB1 cohort, supporting the role of CRB1 in foveal development. FH was associated with poorer BCVA and abnormal retinal morphology. Nonetheless, its presence did not alter the disease progression.

Cleanup of Cr(VI)-polluted groundwater using immobilized bacterial consortia via bioreduction mechanisms.

Cr(VI) bioreduction has become a remedial alternative for Cr(VI)-polluted site cleanup. However, lack of appropriate Cr(VI)-bioreducing bacteria limit the field application of the in situ bioremediation process. In this study, two different immobilized Cr(VI)-bioreducing bacterial consortia using novel immobilization agents have been developed for Cr(VI)-polluted groundwater remediation: (1) granular activated carbon (GAC) + silica gel + Cr(VI)-bioreducing bacterial consortia (GSIB), and (2) GAC + sodium alginate (SA) + polyvinyl alcohol (PVA) + Cr(VI)-bioreducing bacterial consortia (GSPB). Moreover, two unique substrates [carbon-based agent (CBA) and emulsified polycolloid substrate (EPS)] were developed and used as the carbon sources for Cr(VI) bioreduction enhancement. The microbial diversity, dominant Cr-bioreducing bacteria, and changes of Cr(VI)-reducing genes (nsfA, yieF, and chrR) were analyzed to assess the effectiveness of Cr(VI) bioreduction. Approximately 99% of Cr(VI) could be bioreduced in microcosms with GSIB and CBA addition after 70 days of operation, which caused increased populations of total bacteria, nsfA, yieF, and chrR from 2.9 × 108 to 2.1 × 1012, 4.2 × 104 to 6.3 × 1011, 4.8 × 104 to 2 × 1011, and 6.9 × 104 to 3.7 × 107 gene copies/L. In microcosms with CBA and suspended bacteria addition (without bacterial immobilization), the Cr(VI) reduction efficiency dropped to 60.3%, indicating that immobilized Cr-bioreducing bacteria supplement could enhance Cr(VI) bioreduction. Supplement of GSPB led to a declined bacterial growth due to the cracking of the materials. The addition of GSIB and CBA could establish a reduced condition, which favored the growth of Cr(VI)-reducing bacteria. The Cr(VI) bioreduction efficiency could be significantly improved through adsorption and bioreduction mechanisms, and production of Cr(OH)3 precipitates confirmed the occurrence of Cr(VI) reduction. The main Cr-bioreducing bacteria included Trichococcus, Escherichia-Shigella, and Lactobacillus. Results suggest that the developed GSIB bioremedial system could be applied to cleanup Cr(VI)-polluted groundwater effectively.

Electronic Structure and Chemical Bonding of the First-, Second-, and Third-Row-Transition-Metal Monoborides: The Formation of Quadruple Bonds in RhB, RuB, and TcB.

Boron presents an important role in chemistry, biology, and materials science. Diatomic transition-metal borides (MBs) are the building blocks of many complexes and materials, and they present unique electronic structures with interesting and peculiar properties and a variety of bonding schemes which are analyzed here. In the first part of this paper, we present a review on the available experimental and theoretical studies on the first-row-transition-metal borides, i.e., ScB, TiB, VB, CrB, MnB, FeB, CoB, NiB, CuB, and ZnB; the second-row-transition-metal borides, i.e., YB, ZrB, NbB, MoB, TcB, RuB, RhB, PdB, AgB, and CdB; and the third-row-transition-metal borides, i.e., LaB, HfB, TaB, WB, ReB, OsB, IrB, PtB, AuB, and HgB. Consequently, in the second part, the second- and third-row MBs are studied via DFT calculations using the B3LYP, TPSSh, and MN15 functionals and, in some cases, via multi-reference methods, MRCISD+Q, in conjunction with the aug-cc-pVQZ-PPM/aug-cc-pVQZB basis sets. Specifically, bond distances, dissociation energies, frequencies, dipole moments, and natural NPA charges are reported. Comparisons between MB molecules along the three rows are presented, and their differences and similarities are analyzed. The bonding of the diatomic borides is also described; it is found that, apart from RhB(X1Σ+), which was just recently found to form quadruple bonds, RuB(X2Δ) and TcB(X3Σ-) also form quadruple σ2σ2π2π2 bonds in their X states. Moreover, to fill the gap existing in the current literature, here, we calculate the TcB molecule.

Current perspectives in Leber congenital amaurosis type 8 mouse modeling.

Mutations in the CRB1 (Crumbs homolog 1) cause rare retinal diseases like retinitis pigmentosa type 12 (RP12) and Leber congenital amaurosis type 8 (LCA8). RP12 results in progressively worsening peripheral vision, whereas LCA8 causes severe visual impairment at birth or in early life. While several mouse models have been proposed for RP12, few replicate the full spectrum of human LCA8 pathology, such as disorganized retinal layering, abnormal retinal thickening, pigmentary defects, hyperreflective lesions, and severely attenuated electroretinogram responses at birth. Six models have been proposed utilizing the Cre-loxP system to delete candidate genes in specific retinal cell types and developmental stages. The model ablating Crb1 and its homolog Crb2 (using mRx-Cre) from the beginning of the eye development is the most complete as it shows blindness during the eye-opening stage, pigmentary defects in the RPE, ganglion cell layer heterotopia, disruption of retinal lamination, and acellular patches. LCA8 represents a unique type of retinal dystrophy among LCA subtypes, driven by dysfunctional retinal progenitor cells during eye development. In contrast, other LCA types and RP12 are caused by photoreceptor defects. Therefore, the most accurate LCA8-like mouse model must target both alleles of the Crb1 and Crb2 genes in the optic vesicle or earlier.

Antibiotic enhances the spread of antibiotic resistance among chlorine-resistant bacteria in drinking water distribution system.

The extensive use of antibiotics leads to the occurrences of antibiotic resistance genes (ARGs) in aquatic environment. As an emerging environmental pollutant, its pollution in aquatic environment has aroused widespread concern. However, the residues of antibiotics and antibiotic resistance genes in drinking water distribution system were barely reported up to now. Here, we studied the correlation and coordination between chlorine resistance mechanism and antibiotic resistance mechanism of chlorine-resistant bacteria. Antibiotics induce the resistance of chlorine-resistant bacteria (CRB) to NaClO, so that low-dose disinfectants can not inactivate CRB. We put forward a strategy to control the growth of CRB by controlling the concentration of biodegradable dissolved organic carbon (BDOC) in the front section of the water network. Moreover, We screened two strains of chlorine-resistant bacteria with different antibiotic resistance after mixed culture, the results showed that antibiotic resistance could spread horizontally among different kinds of bacteria. Then, the non-pathogenic bacteria can be used as a carrier, causing the pathogen to become resistant to antibiotic, and ultimately pose harm to human health. Generally, the antibiotic, antibiotic resistant genes, and the chlorine disinfectants added in water treatment plants will interact with bacteria in the water supply pipe network, which causes pollution to drinking water.

Strategy for enhancing Cr(VI)-contaminated soil remediation and safe utilization by microbial-humic acid-vermiculite-alginate immobilized biocomposite.

Bioreduction is an efficient approach to in-situ remediate Cr(VI)-contaminated soil, but further strengthening methods are still urgently needed. Herein, a novel immobilized biocomposite (B-HA-VE-SA) was successfully synthesized by embedding a efficient strain Bacillus sp. CRB-7 with humic acid (HA) combined vermiculite (VE) and sodium alginate (SA). The performance and enhancement mechanism of the immobilized biocomposite on remediating Cr(VI)-contaminated soil were also investigated by analyzing the whole-genome of CRB-7, Cr(VI) detoxification, soil microecological regulation, and subsequent crop growth response. Genomic annotation demonstrated that CRB-7 contains multiple genes contributed to Cr(VI) tolerance, Cr(VI) reduction and other metals resistance. Results showed that embedded CRB-7 biocomposites exhibited more effective reduction of Cr(VI) in soil compared with control and free CRB-7 treatment, especially B-HA-VE-SA achieved the highest Cr(VI) removal efficiency (96.18%) and the residual Cr proportion (49.04%) via multiple mechanisms including carrier effects, nutrient sustained-release, and electron-shuttle effect enhanced the bioremediation process. Furthermore, the synergies of CRB-7 and immobilizers (HA, VE and SA) significantly improved soil microecology (soil enzyme activities, microbial quantity and diversity), and engendered the evolution of microbial community composition and functional pathways. Consequently, pot experiments (Brassica napus L.) verified the plant-growth-promoting (12.00-18.00% and 43.82-69.00% higher in emergence rate and biomass) and Cr-accumulation-reducing effects (19.47-91.09% and 29.11-89.80% lower in root and aerial parts) of free and immobilized CRB-7. Taken together, these findings highlighted the superiority of B-HA-VE-SA in simultaneous remediation, microecological improvement and safe utilization of Cr(VI)-contaminated soil.

Crumbs2 Is an Essential Slit Diaphragm Protein of the Renal Filtration Barrier.

BACKGROUND: Crumbs2 is expressed at embryonic stages as well as in the retina, brain, and glomerular podocytes. Recent studies identified CRB2 mutations as a novel cause of steroid-resistant nephrotic syndrome (SRNS). METHODS: To study the function of Crb2 at the renal filtration barrier, mice lacking Crb2 exclusively in podocytes were generated. Gene expression and histologic studies as well as transmission and scanning electron microscopy were used to analyze these Crb2podKO knockout mice and their littermate controls. Furthermore, high-resolution expansion microscopy was used to investigate Crb2 distribution in murine glomeruli. For pull-down experiments, live cell imaging, and transcriptome analyses, cell lines were applied that inducibly express fluorescent protein-tagged CRB2 wild type and mutants. RESULTS: Crb2podKO mice developed proteinuria directly after birth that preceded a prominent development of disordered and effaced foot processes, upregulation of renal injury and inflammatory markers, and glomerulosclerosis. Pull-down assays revealed an interaction of CRB2 with Nephrin, mediated by their extracellular domains. Expansion microscopy showed that in mice glomeruli, Crb2 and Nephrin are organized in adjacent clusters. SRNS-associated CRB2 protein variants and a mutant that lacks a putative conserved O-glycosylation site were not transported to the cell surface. Instead, mutants accumulated in the ER, showed altered glycosylation pattern, and triggered an ER stress response. CONCLUSIONS: Crb2 is an essential component of the podocyte's slit diaphragm, interacting with Nephrin. Loss of slit diaphragm targeting and increasing ER stress are pivotal factors for onset and progression of CRB2-related SRNS.

Boron recovery from desalination seawater brines by selective ion exchange resins.

The European Union (EU) depends on third markets to supply many important raw materials. Increasing the circularity of critical raw materials within the EU is important not only from an environmental perspective, but also as a competitive advantage for the EU economy. In the case of boron, the EU's import dependency is about 100%. This work aims to evaluate the boron recovery from seawater desalination plants (SWDP) brines using ion-exchange resins in a circular economy approach. Commercial boron selective resins Purolite S108, DIAION CRB03 and CRB05 were tested and compared on batch and dynamic experiments. Thermodynamic and kinetic experiments were performed, and results were fitted by linear and non-linear models. After a comparison, results showed a good fit to the Langmuir isotherm and the pseudo-second order model, respectively, for all the commercial resins tested. The DIAION CRB03 resin presented higher sorption capacity and percentage of boron sorbed than the other resins and was selected as the best option for boron recovery from SWDP brine. Dynamic experiments in fixed bed column using DIAION CRB03 resulted in a sorption capacity of 13 mg/g of resin, a boron recovery of 98% and a concentration factor of 30, for an initial boron concentration of 50 mg/L. In addition, an economic analysis was carried out as a preliminary estimate of the revenues obtained from the production of boric acid from the brine produced by El Prat desalination plant.