RNA helicase DExD/H-box 5 modulates intestinal microbiota in mice.

The RNA helicase DExD/H-box (DDX) family of proteins plays a central role in host cellular RNA metabolism, including mRNA regulation, microRNA biogenesis, and ribosomal processing. DDX5, also known as p68, promotes viral replication and tumorigenesis. However, there have been no studies on the regulation of the intestinal microbiota by DDX family proteins. We constructed DDX5 knockout mice (Ddx5+/-) using CRISPR/CAS9 technology. Subsequently, DDX5 knockout mice were analyzed for PCR products, mRNA levels, protein expression, immunohistochemistry, and histopathological lesions. Fecal (n = 12) and ileum (n = 12) samples were collected from the Ddx5+/- and wild-type (Ddx5+/+) mice. The diversity, richness, and structural separation of the intestinal microbiota of the Ddx5+/- and Ddx5+/+ mice were determined by 16S rRNA sequencing and analysis. Ddx5+/- mice were successfully established, and the ileum had normal morphology, a clear layer of tissue structures, and neatly arranged cupped cells. DDX5 knockout mice did not exhibit adverse effects on the ileal tissue. Microbial diversity and abundance were not significantly different, but the microbial structure of the intestinal microbiota was clustered separately between Ddx5+/+ and Ddx5+/- mice. Furthermore, we found that the relative abundance of Akkermansia and Clostridium_sensu_stricto_1 in the Ddx5+/- mice was significantly lower than in the Ddx5+/+ mice. These analyses indicated specific interactions between the intestinal microbiota and DDX5 protein. Our results indicate that DDX5 has a significant effect on the composition of the intestinal microbiota in mice, suggesting its potential as a promising novel target for the treatment of inflammation and tumorigenesis in the intestine.

Novel mesothelin-targeted chimeric antigen receptor-modified UNKT cells are highly effective in inhibiting tumor progression.

The design of chimeric antigen receptors (CAR) significantly enhances the antitumor efficacy of T cells. Although some CAR-T products have been approved by FDA in treating hematological tumors, adoptive immune therapy still faces many difficulties and challenges in the treatment of solid tumors. In this study, we reported a new strategy to treat solid tumors using a natural killer-like T (NKT) cell line which showed strong cytotoxicity to lyse 15 cancer cell lines, safe to normal cells and had low or no Graft-versus-host activity. We thus named it as universal NKT (UNKT). In both direct and indirect 3D tumor-like organ model, UNKT showed efficient tumor-killing properties, indicating that it could penetrate the microenvironment of solid tumors. In mesothelin (MSLN)-positive tumor cells (SKOV-3 and MCF-7), MSLN targeting CAR modified-UNKT cells had enhanced killing potential against MSLN positive ovarian cancer compared with the wild type UNKT, as well as MSLN-CAR-T cells. Compared with CAR-T, Single-cell microarray 32-plex proteomics revealed CAR-UNKT cells express more effector cytokines, such as perforin and granzyme B, and less interleukin-6 after activation. Moreover, our CAR-UNKT cells featured in more multifunctionality than CAR-T cells. CAR-UNKT cells also demonstrated strong antitumor activity in mouse models of ovarian cancer, with the ability to migrate and infiltrate the tumor without inducing immune memory. The fast-in and -out, enhanced and prolonged tumor killing properties of CAR-UNKT suggested a novel cure option of cellular immunotherapy in the treatment of MSLN-positive solid tumors.

An atypical anti-GBM disease complicated by idiopathic nodular glomerulosclerosis: Case report.

Both atypical anti-glomerular basement membrane (anti-GBM) disease and idiopathic nodular glomerulosclerosis are rare diseases. We report a case of a 53-year-old non-diabetic male who presented with leg edema, nephritic range proteinuria, microscopic hematuria, and decreased renal function. The renal biopsy demonstrated membranoproliferative glomerulonephritis (MPGN) pattern of glomerular injury with focal crescent and segmental nodular glomerulosclerosis. The immunofluorescence studies showed intense linear IgG (IgG1 and IgG4) deposits along the GBM but negative serology. Electron microscopy demonstrated GBM thickening and fibrillar deposition. The presence of MPGN with crescents and the linear IgG along the GBM were consistent with a diagnosis of atypical ant-GBM disease. Superimposed nodular glomerulosclerosis was considered to be idiopathic by excluding other glomerular diseases characterized by fibrillar deposition and nodular glomerulosclerosis. Both diseases were found to have a strong causative association with patient's history of long-term heavy smoking. This unusual case with combination of atypical anti-GBM disease and idiopathic nodular glomerulosclerosis, has brought great challenge for the diagnosis and also made the clinical course highly complicated. This nodular glomerulosclerosis with anti-GBM-like glomerulonephritis may represent a distinct pattern of kidney injury observed in heavy smokers.

Enhanced Activity of Enzyme Immobilized on Hydrophobic ZIF-8 Modified by Ni2+ Ions.

The development of efficient enzyme immobilization to promote their recyclability and activity is highly desirable. Zeolitic imidazolate framework-8 (ZIF-8) has been proved to be an effective platform for enzyme immobilization due to its easy preparation and biocompatibility. However, the intrinsic hydrophobic characteristic hinders its further development in this filed. Herein, a facile synthesis approach was developed to immobilize pepsin (PEP) on the ZIF-8 carrier by using Ni2+ ions as anchor (ZIF-8@PEP-Ni). By contrast, the direct coating of PEP on the surface of ZIF-8 (ZIF-8@PEP) generated significant conformational changes. Electrochemical oxygen evolution reaction (OER) was employed to study the catalytic activity of immobilized PEP. The ZIF-8@PEP-Ni composite attains remarkable OER performance with an ultralow overpotential of only 127 mV at 10 mA cm-2 , which is much lower than the 690 and 919 mV overpotential values of ZIF-8@PEP and PEP, respectively.

Microfluidic Organs-on-a-Chip for Modeling Human Infectious Diseases.

Infectious diseases present tremendous challenges to human progress and public health. The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the associated coronavirus disease 2019 (COVID-19) pandemic continue to pose an imminent threat to humanity. These infectious diseases highlight the importance of developing innovative strategies to study disease pathogenesis and protect human health. Although conventional in vitro cell culture and animal models are useful in facilitating the development of effective therapeutics for infectious diseases, models that can accurately reflect human physiology and human-relevant responses to pathogens are still lacking. Microfluidic organs-on-a-chip (organ chips) are engineered microfluidic cell culture devices lined with living cells, which can resemble organ-level physiology with high fidelity by rebuilding tissue-tissue interfaces, mechanical cues, fluidic flow, and the biochemical cellular microenvironment. They present a unique opportunity to bridge the gap between in vitro experimental models and in vivo human pathophysiology and are thus a promising platform for disease studies and drug testing. In this Account, we first introduce how recent progress in organ chips has enabled the recreation of complex pathophysiological features of human infections in vitro. Next, we describe the progress made by our group in adopting organ chips and other microphysiological systems for the study of infectious diseases, including SARS-CoV-2 viral infections and intrauterine bacterial infections. Respiratory symptoms dominate the clinical manifestations of many COVID-19 patients, even involving the systemic injury of many distinct organs, such as the lung, the gastrointestinal tract, and so forth. We thus particularly highlight our recent efforts to explore how lung-on-a-chip and intestine-on-a-chip might be useful in addressing the ongoing viral pandemic of COVID-19 caused by SARS-CoV-2. These organ chips offer a potential platform for studying virus-host interactions and human-relevant responses as well as accelerating the development of effective therapeutics against COVID-19. Finally, we discuss opportunities and challenges in the development of next-generation organ chips, which are urgently needed for developing effective and affordable therapies to combat infectious diseases. We hope that this Account will promote awareness about in vitro organ microphysiological systems for modeling infections and stimulate joint efforts across multiple disciplines to understand emerging and re-emerging pandemic diseases and rapidly identify innovative interventions.

Comparative analysis of gut microbiota in healthy and diarrheic yaks.

BACKGROUND: Yak (Bos grunniens) mainly inhabiting Tibet Plateau, displayed a high incidence of diarrhea due to harsh living environment and nutritional deficit. Gut microbial community has been reported to be closely related to many diseases including diabetes, obesity and inflammatory bowel disease, but information regarding diarrheic influence on gut microbiota in yaks remains scarce. Here, this study was performed to investigate the gut bacterial and fungal alternations of diarrheic yaks. RESULTS: Results revealed that the gut bacterial and fungal communities of diarrheic yaks showed a distinct decline in alpha diversity, accompanied by significant shifts in taxonomic compositions. Specifically, diarrhea caused a distinct increase in the relative abundance of 1 phylum and 8 genera as well as a distinct decrease in 3 phyla and 30 genera. Fungal taxonomic analysis indicated that the relative richness of 1 phylum and 2 genera dramatically increased, whereas the relative richness of 2 phylum and 43 genera significantly decreased during diarrhea. Surprisingly, 2 bacterial genera and 5 fungal genera even cannot be detected in the gut microbiota of diarrheic yaks. CONCLUSIONS: In summary, this study indicated that the gut bacterial and fungal compositions and diversities of yaks altered significantly during diarrhea. Moreover, these findings also contribute to understanding the gut microbial composition and diversity of yaks and developing strategies to alleviate and prevent diarrhea from gut microbial perspective.

Anionic Porous Zn-Metalated Porphyrin Metal-Organic Framework with PtS Topology for Gas-Phase Photocatalytic CO2 Reduction.

Presented here are the synthesis and gas-phase photocatalytic CO2 reduction of an anionic porous Zn-metalated porphyrin metal-organic framework (MOF) induced by an ionic liquid. The desired CO2 affinity and deep conduction band position of the MOF catalyst provide strong kinetic and thermodynamic advantages for photocatalytic CO2 to CH4 conversion with high selectivity (∼70%) in H2O vapor.

Isolating Fe-O2 Intermediates in Dioxygen Activation by Iron Porphyrin Complexes.

Dioxygen (O2) is an environmentally benign and abundant oxidant whose utilization is of great interest in the design of bioinspired synthetic catalytic oxidation systems to reduce energy consumption. However, it is unfortunate that utilization of O2 is a significant challenge because of the thermodynamic stability of O2 in its triplet ground state. Nevertheless, nature is able to overcome the spin state barrier using enzymes, which contain transition metals with unpaired d-electrons facilitating the activation of O2 by metal coordination. This inspires bioinorganic chemists to synthesize biomimetic small-molecule iron porphyrin complexes to carry out the O2 activation, wherein Fe-O2 species have been implicated as the key reactive intermediates. In recent years, a number of Fe-O2 intermediates have been synthesized by activating O2 at iron centers supported on porphyrin ligands. In this review, we focus on a few examples of these advances with emphasis in each case on the particular design of iron porphyrin complexes and particular reaction environments to stabilize and isolate metal-O2 intermediates in dioxygen activation, which will provide clues to elucidate structures of reactive intermediates and mechanistic insights in biological processes.

Value of [68Ga]Ga-FAPI-04 imaging in the diagnosis of renal fibrosis.

PURPOSE: Renal fibrosis is a pathological state in the progression of chronic kidney disease. Early detection and treatment are vital to prolonging patient survival. Renal puncture examination is the gold standard for renal fibrosis, but it has several limitations. This study aims to evaluate the diagnostic performance of a novel PET radiotracer, [68Ga]Ga-fibroblast activation protein inhibitor (FAPI)-04, which specifically images fibroblast activation protein (FAP) expression for renal fibrosis. METHODS: All patients underwent renal puncture before receiving [68Ga]Ga-FAPI-04 PET/CT imaging. They then underwent [68Ga]Ga-FAPI-04 PET/CT and immunochemistry examinations. The data obtained were analyzed. RESULTS: The [68Ga]Ga-FAPI-04 PET/CT examination results demonstrated that almost all patients (12/13) exhibited increased radiotracer uptake. The maximum standardized uptake value (SUVmax) in patients with mild, moderate, and severe fibrosis was 3.92 ± 1.50, 5.98 ± 1.6, and 7.67 ± 2.23, respectively. CONCLUSION: Compared with renal puncture examination, non-invasive imaging of FAP expression through [68Ga]Ga-FAPI-04 PET/CT quickly demonstrates bilateral kidney conditions with high sensitivity. [68Ga]Ga-FAPI-04 PET/CT can facilitate the evaluation of disease progression, diagnosis, and the development of a treatment plan.

Efficient Energy-Transfer-Induced High Photoelectric Conversion in a Dye-Encapsulated Ionic Pyrene-Based Metal-Organic Framework.

The relationship between the aggregation states of pyrene-based linkers and the photoluminescence/photoelectric performance was well studied by the formation of an anionic metal-organic framework, [BMI]2[Mg3(TBAPy)2(H2O)4]·2dioxane, which shows highly enhanced light-harvesting and photoelectric conversion efficiency by the encapsulation of D-π-A cation dyes.

Hexanuclear Zn(II)-Induced Dense π-Stacking in a Metal-Organic Framework Featuring Long-Lasting Room Temperature Phosphorescence.

A new strategy to enhance the room temperature phosphorescence performance has been developed through hexanuclear Zn(II)-cluster-induced dense π-stacking in a metal-organic framework matrix. The synergistic effect of metal clusters and large overlap of π-conjugated dimers facilitate the phosphorescence emission, migration, and separation of charge carriers for excellent photocatalytic activity.

Highly Dense Packing of Chromophoric Linkers Achievable in a Pyrene-Based Metal-Organic Framework for Photoelectric Response.

Highly dense packing of chromophoric linkers is achieved in a novel pyrene-based metal-organic framework (MOF), [Zn(TBAPy)1/2(H2O)2], induced by an ionic liquid. This MOF displays a quick response to visible-light irradiation (photocurrent density of up to 4.492 µA cm-2) and is capable of repetitive on-off photocurrent switching with a large on-off ratio (37.55).

Bioinspired Engineering of Organ-on-Chip Devices.

The human body can be viewed as an organism consisting of a variety of cellular and non-cellular materials interacting in a highly ordered manner. Its complex and hierarchical nature inspires the multi-level recapitulation of the human body in order to gain insights into the inner workings of life. While traditional cell culture models have led to new insights into the cellular microenvironment and biological control in vivo, deeper understanding of biological systems and human pathophysiology requires the development of novel model systems that allow for analysis of complex internal and external interactions within the cellular microenvironment in a more relevant organ context. Engineering organ-on-chip systems offers an unprecedented opportunity to unravel the complex and hierarchical nature of human organs. In this chapter, we first highlight the advances in microfluidic platforms that enable engineering of the cellular microenvironment and the transition from cells-on-chips to organs-on-chips. Then, we introduce the key features of the emerging organs-on-chips and their proof-of-concept applications in biomedical research. We also discuss the challenges and future outlooks of this state-of-the-art technology.

A Microfluidic Strategy for Controllable Generation of Water-in-Water Droplets as Biocompatible Microcarriers.

Droplet microfluidics has been widely applied in functional microparticles fabricating, tissue engineering, and drug screening due to its high throughput and great controllability. However, most of the current droplet microfluidics are dependent on water-in-oil (W/O) systems, which involve organic reagents, thus limiting their broader biological applications. In this work, a new microfluidic strategy is described for controllable and high-throughput generation of monodispersed water-in-water (W/W) droplets. Solutions of polyethylene glycol and dextran are used as continuous and dispersed phases, respectively, without any organic reagents or surfactants. The size of W/W droplets can be precisely adjusted by changing the flow rate of dispersed and continuous phases and the valve switch cycle. In addition, uniform cell-laden microgels are fabricated by introducing the alginate component and rat pancreatic islet (ß-TC6) cell suspension to the dispersed phase. The encapsulated islet cells retain high viability and the function of insulin secretion after cultivation for 7 days. The high-throughput droplet microfluidic system with high biocompatibility is stable, controllable, and flexible, which can boost various chemical and biological applications, such as bio-oriented microparticles synthesizing, microcarriers fabricating, tissue engineering, etc.

A Biomimetic Human Gut-on-a-Chip for Modeling Drug Metabolism in Intestine.

Drug metabolism in the intestine is considered to substantially contribute to the overall first-pass metabolism, which has been neglected for a long time. It is highly desirable to develop a reliable model to evaluate drug metabolism in the intestine in vitro. In this work, we made the first attempt to develop a biomimetic human gut-on-a-chip for modeling drug metabolism in intestine. In this chip, constant flow, together with porous nitrocellulose membrane and collagen I, mimics an in vivo-like intestinal microenvironment. The Caco-2 cells grown in the chip formed a compact intestinal epithelial layer with continuous expression of the tight junction protein, ZO-1. Furthermore, higher gene expression of villin, sucrase-isomaltase, and alkaline phosphatase demonstrated that cells in the biomimetic human gut-on-a-chip device were more mature with near-physiological functions compared to the control on planar substrate. In particular, cellular metabolic activity was assessed on different substrates, indicating higher metabolic efficiency of ifosfamide and verapamil in the biomimetic human gut-on-a-chip model. Taken together, our results suggested that this biomimetic human gut-on-a-chip promoted the differentiation of intestinal cells with enhanced functionality by creating a biomimetic 3D microenvironment in vitro. It might offer a bioactive, low-cost, and flexible in vitro platform for studies on intestinal metabolism as well as preclinical drug development.

Gold nanorods decorated with graphene oxide and multi-walled carbon nanotubes for trace level voltammetric determination of ascorbic acid.

An ultra-sensitive sensor is described for the voltammetric determination of ascorbic acid (AA). A glassy carbon electrode (GCE) was modified with graphene oxide (GO), multi-walled carbon nanotubes (MWCNTs) and gold nanorods (AuNRs). GO was used to prevent the aggregation of MWCNTs. The integration of positively charged AuNRs reduces the overpotential and increases the peak current of AA oxidation. Figures of merit of this sensor, typically operated at a low working potential of 0.036 V (vs. Ag/AgCl), include a low detection limit (0.85 nM), high sensitivity (7.61 µA·µM-1·cm-2) and two wide linear ranges (from 1 nM to 0.5 µM and from 1 µM to 8 mM). The use of GO simplifies the manufacture and results in a highly reproducible and stable sensor. It was applied to the quantification of AA in spiked serum. Graphical abstract Graphical abstract contains poor quality and small text inside the artwork. Please do not re-use the file that we have rejected or attempt to increase its resolution and re-save. It is originally poor, therefore, increasing the resolution will not solve the quality problem. We suggest that you provide us the original format. We prefer replacement figures containing vector/editable objects rather than embedded images. Preferred file formats are eps, ai, tiff and pdf.We have provided the original format with the attachments named g.tif. Graphene oxide (GO) in combination with multiwalled carbon nanotubes (MWCNTs) and gold nanorods (AuNRs) were used to construct a sensing interface with outstanding electrocatalytic performance for ascorbic acid detection.

Probing the response of lung tumor cells to inflammatory microvascular endothelial cells on fluidic microdevice.

The development of cancer depends on a complex tissue microenvironment for sustained growth, invasion, and metastasis. The extravasation of tumor cells is a critical event in tumor metastasis. However, the process and mechanism that underlie tumor cell extravasation remain unclear, which restricts the examination of many tumor processes and presents a formidable hurdle to drug development. To explore the initial steps by which lung tumor cells interact with the brain microvascular wall in the course of extravasation, we present a simple, inexpensive, and time-saving microfluidic device to mimic the inflammatory brain microvascular microenvironment and to investigate both the biochemical and mechanical causes of lung tumor cell rolling and adhesion on inflammatory endothelium to analyze the synergistic effects on tumor extravasation under fluidic shear stress conditions. Under microvascular inflammation induced by tumor necrosis factor α, the lung tumor cells (A549 cells) displayed significant adhesion activity. In addition, we found that this situation could be reversed by administration of Rho/Rho-associated protein serine/threonine kinase (ROCK) inhibitor (Y27632). We believe that this promising microdevice-based tumor adhesion and extravasation research platform can be used to study tumor behavior in an inflammatory vascular system and will make a valuable contribution for the investigation of the mechanism of tumor cell extravasation.

Probing the Bi-directional Interaction Between Microglia and Gliomas in a Tumor Microenvironment on a Microdevice.

It has been proven that microglia are involved in both early and late stages of glioma progression and contribute substantially to the tumor mass of gliomas. Because no appropriate in vitro or in vivo investigative approach is available, the dynamic interaction between microglia and gliomas during tumor formation remains unclear. In this study, three types of microfluidic assay were developed to examine the outcomes of the dynamic interaction between microglia and gliomas. Co-migration assay and two-dimensional cell co-culture assay have been used to show that microglial BV-2 cells migrate toward C6 glioma cells and inhibit tumor growth during the early stage of tumorigenesis. However, in three-dimensional cell spheres (three-dimensional cell co-culture assay) that contain a large amount of glioma cells, mimicking the late stage of glioma growth, the phagocytosis of microglia was suppressed, which suggests that glioma cells could reeducate classically activated microglia into a tumor-promoting state at some point during tumor progression. Notably, we found that microglia could contribute to tumor invasion and acquisition of the epithelial-mesenchymal transition phenotype in the glioma microenvironment during the early stage and the late stage of tumor progression. In conclusion, we have developed a potential quantitative method for in vitro study of glioma immunity and provided evidence for the duality of glioma-associated microglia.

[Excessive fluoride increases the expression of osteocalcin in the mouse testis].

OBJECTIVE: To observe the influence of excessive fluoride on the levels of osteocalcin and testosterone in the testis of the male mouse. METHODS: Twenty-four C57BL/6J male mice were equally randomized into a normal control and a fluorosis model group, the former fed on distilled water while the latter on a solution of sodium fluoride (100 mg/L) in distilled water, both for 12 weeks. Then, the level of osteocalcin in the testis tissue was measured with the immunohistochemical streptavidin-peroxidase (SP) method and those of osteocalcin and testosterone in the serum determined by ELISA. RESULTS: After 12 weeks of fluoride intervention, the level of serum osteocalcin was significantly higher in the fluorosis models than in the normal controls (ï¼»68.05 ± 5.32ï¼½ vs ï¼»47.50 ± 5.73ï¼½ pg/mL, F = 11.901, P = 0.008), while that of testosterone markedly lower in the former than the latter group (ï¼»8.07 ± 1.35ï¼½ vs ï¼»12.94 ± 3.09ï¼½ ng/mL, F = 2.313, P = 0.006). The results of immunohistochemical SP showed the expression of osteocalcin in the cell membrane and cytoplasm of the fluorosis models, which was evidently higher than in the normal controls. CONCLUSIONS: Twelve-week intake of 100 mg/L fluoride solution can decrease the level of testosterone and increase the expression of osteocalcin in the testis of the male mouse.