Delivery of Stem Cells and BMP-2 With Functionalized Self-Assembling Peptide Enhances Regeneration of Infarcted Myocardium

Stem cell transplantation is a promising therapeutic strategy for myocardial infarction (MI). However, engraftment, survival and differentiation of the transplanted stem cells in ischemic and inflammatory microenvironment are poor. We designed a novel self-assembly peptide (SAP) by modifying the peptide RADA16 with cell-adhesive motif and BMP-2 (bone morphogenetic protein-2)-binding motif. Effects of the functionalized SAP on adhesion, survival and differentiation of c-kit+ MSCs (mesenchymal stem cells) were examined. Myocardial regeneration, neovascularization and cardiac function were assessed after transplantation of the SAP loading c-kit+ MSCs and BMP-2 in rat MI models. The SAP could spontaneously assemble into well-ordered nanofibrous scaffolds. The cells adhered to the SAP scaffolds and spread well. The SAP protected the cells in the condition of hypoxia and serum deprivation. Following degradation of the SAP, BMP-2 was released sustainedly and induced c-kit+ MSCs to differentiate into cardiomyocytes. At four weeks after transplantation of the SAP loading c-kit+ MSCs and BMP-2, myocardial regeneration and angiogenesis were enhanced, and cardiac function was improved significantly. The cardiomyocytes differentiated from the engrafted c-kit+ MSCs were increased markedly. The differentiated cells connected with recipient cardiomyocytes to form gap junctions. Collagen volume was decreased dramatically. These results suggest that the functionalized SAP promotes engraftment, survival and differentiation of stem cells effectively. Local sustained release of BMP-2 with SAP is a viable strategy to enhance differentiation of the engrafted stem cells and repair of the infarcted myocardium.

The Inhibition of Fibrosis and Inflammation in Obstructive Kidney Injury via the miR-122-5p/SOX2 Axis Using USC-Exos

Background: Fibrosis and inflammation due to ureteropelvic junction obstruction substantially contributes to poor renal function. Urine-derived stem-cell-derived exosomes (USC-Exos) have therapeutic effects through paracrine. Methods: In vitro, the effects of USC-Exos on the biological functions of HK-2 and human umbilical vein endothelial cells were tested. Cell inflammation and fibrosis were induced by transforming growth factor-β1 and interleukin-1β, and their anti-inflammatory and antifibrotic effects were observed after exogenous addition of USC-Exos. Through high-throughput sequencing of microRNA in USC-Exos, the pathways and key microRNAs were selected. Then, the antifibrotic and anti-inflammatory effects of exosomal miR-122-5p and target genes were verified. The role of the miR-122-5p/SOX2 axis in anti-inflammatory and antifibrotic effects was verified. In vivo, a rabbit model of partial unilateral ureteral obstruction (PUUO) was established. Magnetic resonance imaging recorded the volume of the renal pelvis after modeling, and renal tissue was pathologically analyzed. Results: We examined the role of USC-Exos and their miR-122-5p content in obstructive kidney injury. These Exos exhibit antifibrotic and anti-inflammatory activities. SOX2 is the hub gene in PUUO and negatively related to renal function. We confirmed the binding relationship between miR-122-5p and SOX2. The anti-inflammatory and antifibrotic effects of miR-122-5p were inhibited, indicating that miR-122-5p has anti-inflammatory and antifibrotic effects by inhibiting SOX2 expression. In vivo, the PUUO group showed typical obstructive kidney injury after modeling. After USC-Exo treatment, the shape of the renal pelvis shown a remarkable improvement, and inflammation and fibrosis decreased. Conclusions: We confirmed that miR-122-5p from USC-Exos targeting SOX2 is a new molecular target for postoperative recovery treatment of obstructive kidney injury.

Hydrostatic pressure mediates epithelial-mesenchymal transition of cholangiocytes through RhoA/ROCK and TGF-β/smad pathways

Biomechanical cue within the tissue microenvironment is known to play a critical role in regulating cell behaviors and maintaining tissue homeostasis. As hydrostatic pressure often increases in biliary system under pathological states, we investigated the effect of the moderate elevation of the hydrostatic pressure on biliary epithelial cells, especially on the epithelial-mesenchymal transition (EMT). Human intrahepatic biliary epithelial cells were loaded to hydrostatic pressure using a commercial device. We found that loading the cells to 50 mmHg hydrostatic pressure induced obvious morphological changes and significantly upregulated vimentin, ZEB1, and pSmad2/3, fibronectin, and collagen 1α. All changes induced by hydrostatic pressure loading were effectively mitigated by either ROCK inhibitor (Y-27632) or ALK5 inhibitor (SB-431542). Our in vitro experimental data suggests that hydrostatic pressure loading induces EMT of cholangiocytes through RhoA/ROCK and TGF-β/Smad pathways. Elevated hydrostatic pressure in biliary duct system under pathological states may promote the biliary epithelial cells shifting to profibrotic and mesenchymal characteristics.

Anciently duplicated genes continuously recruited to heart expression in vertebrate evolution are associated with heart chamber increase

Although gene/genome duplications in the early stage of vertebrates have been thought to provide major resources of raw genetic materials for evolutionary innovations, it is unclear whether they continuously contribute to the evolution of morphological complexity during the course of vertebrate evolution, such as the evolution from two heart chambers (fishes) to four heart chambers (mammals and birds). We addressed this issue by our heart RNA-Seq experiments combined with published data, using 13 vertebrates and one invertebrate (sea squirt, as an outgroup). Our evolutionary transcriptome analysis showed that number of ancient paralogous genes expressed in heart tends to increase with the increase of heart chamber number along the vertebrate phylogeny, in spite that most of them were duplicated at the time near to the origin of vertebrates or even more ancient. Moreover, those paralogs expressed in heart exert considerably different functions from heart-expressed singletons: the former are functionally enriched in cardiac muscle and muscle contraction-related categories, whereas the latter play more basic functions of energy generation like aerobic respiration. These findings together support the notion that recruiting anciently paralogous genes that are expressed in heart is associated with the increase of chamber number in vertebrate evolution.

CRP inhibits the osteoblastic differentiation of OPCs via the up-regulation of primary cilia and repression of the Hedgehog signaling pathway

Inflammation disrupts bone metabolism and leads to bone damage. C-reactive protein (CRP) is a typical inflammation marker. Although CRP measurement has been conducted for many decades, how osteoblastic differentiation influences molecular mechanisms remains largely unknown. The present study attempted to investigate the effects of CRP on primary cultured osteoblast precursor cells (OPCs) while elucidating the underlying molecular mechanisms. OPCs were isolated from suckling Sprague-Dawleyrats. Fewer OPCs were observed after recombinant C-reactive protein treatment. In a series of experiments, CRP inhibited OPC proliferation, osteoblastic differentiation, and the OPC gene expression of the hedgehog (Hh) signaling pathway. The inhibitory effect of CRP on OPC proliferation occurred via blockade of the G1-S transition of the cell cycle. In addition, the regulation effect of proto cilium on osteoblastic differentiation was analyzed using the bioinformatics p. This revealed the primary cilia activation of recombinant CRP effect on OPCs through in vitro experiments. A specific Sonic Hedgehog signaling agonist (SAG) rescued osteoblastic differentiation inhibited by recombinant CRP. Moreover, chloral hydrate, which removes primary cilia, inhibited the Suppressor of Fused (SUFU) formation and blocked Gli2 degradation. This counteracted osteogenesis inhibition caused by CRP. Therefore, these data depict that CRP can inhibit the proliferation and osteoblastic differentiation of OPCs. The underlying mechanism could be associated with primary cilia activation and Hh pathway repression.

Comparative transcriptome analysis and genetic dissection of vegetative branching traits in foxtail millet (Setaria italica)

KEY MESSAGE

Two major genetic loci, qTN5.1 and qAB9.1, were identified and finely mapped to the 255 Kb region with one potential candidate gene for tiller number and the 521 Kb region with eight candidate genes for axillary branch number, respectively. Vegetative branching including tillering and axillary branching are vital traits affecting both the plant architecture and the biomass in cereal crops. However, the mechanism underlying the formation of vegetative branching in foxtail millet is largely unknown. Here, a foxtail millet cultivar and its bushy wild relative Setaria viridis accession were used to construct segregating populations to identify candidate genes regulating tiller number and axillary branch number. Transcriptome analysis using vegetative branching bud samples of parental accessions was performed, and key differentially expressed genes and pathways regulating vegetative branching were pointed out. Bulk segregant analysis on their F2:3 segregating population was carried out, and a major QTL for tiller number (qTN5.1) and two major QTLs for axillary branch number (qAB2.1 and qAB9.1) were detected. Fine-mapping strategy was further performed on F2:4 segregate population, and Seita.5G356600 encoding β-glucosidase 11 was identified as the promising candidate gene for qTN5.1, and eight genes, especially Seita.9G125300 and Seita.9G125400 annotated as B-S glucosidase 44, were finally identified as candidate genes for regulating axillary branching. Findings in this study will help to elucidate the genetic basis of the vegetative branching formation of foxtail millet and lay a foundation for breeding foxtail millet varieties with ideal vegetative branching numbers.

Characterization of wheat Wrab18 gene promoter and expression analysis under abiotic stress

BACKGROUND

Promoters play key roles in plant gene expression in complex and varied natural environments. The type and amount of cis-acting elements in the promoter sequence tend to indicate the response of genes to induction factors. WRAB18 is a group III member of the late embryogenesis abundant (LEA) protein family that performs multiple functions in plant stress physiology. To elucidate the particularly biological effects of WRAB18 on stress, exploration of its promoter sequence is necessary.

METHODS AND RESULTS

In this study, the full-length and promoter sequences of Wrab18 were isolated from the Zhengyin 1 cultivar of Triticum aestivum. The gene sequences and cis-acting elements in the promoter were analyzed using the Plant Promoter Database and bioinformatics methods. The results showed that Wrab18 possessed one intron with 100 bp, the promoter sequence contained various stress-related cis-acting elements, and the functionality of the promoter was checked using green fluorescent protein (GFP) marker protein expression by transient assay in Nicotiana benthamiana. Furthermore, based on promoter prediction analysis, quantitative real-time fluorescent PCR results confirmed the response of gene expression levels to stress factors.

CONCLUSIONS

In summary, the promoter sequence of Wrab18 plays a role in plant stress responses, contains multiple cis-acting elements, and provides insights into the role of WRAB18 in plant resilience to stress. This study has guiding significance for further studies of gene function and mechanism of action, and lays a theoretical foundation for improving wheat quality.

The causal mutation in ARR3 gene for high myopia and progressive color vision defect

The ARR3 gene, also known as cone arrestin, belongs to the arrestin family and is expressed in cone cells, inactivating phosphorylated-opsins and preventing cone signals. Variants of ARR3 reportedly cause X-linked dominant female-limited early-onset (age < 7 years old) high myopia (< - 6D). Here, we reveal a new mutation (c.228T>A, p.Tyr76*) in ARR3 gene that can cause early-onset high myopia (eoHM) limited to female carriers. Protan/deutan color vision defects were also found in family members, affecting both genders. Using ten years of clinical follow-up data, we identified gradually worsening cone dysfunction/color vision as a key feature among affected individuals. We present a hypothesis that higher visual contrast due to the mosaic of mutated ARR3 expression in cones contributes to the development of myopia in female carriers.

An Agrobacterium-Mediated Transient Expression Method for Functional Assay of Genes Promoting Disease in Monocots

Agrobacterium-mediated transient expression (AMTE) has been widely used for high-throughput assays of gene function in diverse plant species. However, its application in monocots is still limited due to low expression efficiency. Here, by using histochemical staining and a quantitative fluorescence assay of β-glucuronidase (GUS) gene expression, we investigated factors affecting the efficiency of AMTE on intact barley plants. We found prominent variation in GUS expression levels across diverse vectors commonly used for stable transformation and that the vector pCBEP produced the highest expression. Additionally, concurrent treatments of plants with one day of high humidity and two days of darkness following agro-infiltration also significantly increased GUS expression efficiency. We thus established an optimized method for efficient AMTE on barley and further demonstrated its efficiency on wheat and rice plants. We showed that this approach could produce enough proteins suitable for split-luciferase assays of protein-protein interactions on barley leaves. Moreover, we incorporated the AMTE protocol into the functional dissection of a complex biological process such as plant disease. Based on our previous research, we used the pCBEP vector to construct a full-length cDNA library of genes upregulated during the early stage of rice blast disease. A subsequent screen of the library by AMTE identified 15 candidate genes (out of ~2000 clones) promoting blast disease on barley plants. Four identified genes encode chloroplast-related proteins: OsNYC3, OsNUDX21, OsMRS2-9, and OsAk2. These genes were induced during rice blast disease; however, constitutive overexpression of these genes conferred enhanced disease susceptibility to Colletotrichum higginsianum in Arabidopsis. These observations highlight the power of the optimized AMTE approach on monocots as an effective tool for facilitating functional assays of genes mediating complex processes such as plant-microbe interactions.

Ploidy-stratified single cardiomyocyte transcriptomics map Zinc Finger E-Box Binding Homeobox 1 to underly cardiomyocyte proliferation before birth

Whereas cardiomyocytes (CMs) in the fetal heart divide, postnatal CMs fail to undergo karyokinesis and/or cytokinesis and therefore become polyploid or binucleated, a key process in terminal CM differentiation. This switch from a diploid proliferative CM to a terminally differentiated polyploid CM remains an enigma and seems an obstacle for heart regeneration. Here, we set out to identify the transcriptional landscape of CMs around birth using single cell RNA sequencing (scRNA-seq) to predict transcription factors (TFs) involved in CM proliferation and terminal differentiation. To this end, we established an approach combining fluorescence activated cell sorting (FACS) with scRNA-seq of fixed CMs from developing (E16.5, P1, and P5) mouse hearts, and generated high-resolution single-cell transcriptomic maps of in vivo diploid and tetraploid CMs, increasing the CM resolution. We identified TF-networks regulating the G2/M phases of developing CMs around birth. ZEB1 (Zinc Finger E-Box Binding Homeobox 1), a hereto unknown TF in CM cell cycling, was found to regulate the highest number of cell cycle genes in cycling CMs at E16.5 but was downregulated around birth. CM ZEB1-knockdown reduced proliferation of E16.5 CMs, while ZEB1 overexpression at P0 after birth resulted in CM endoreplication. These data thus provide a ploidy stratified transcriptomic map of developing CMs and bring new insight to CM proliferation and endoreplication identifying ZEB1 as a key player in these processes.

A study about management of drugs for leprosy patients under medical monitoring: A solution based on AHP-Electre decision-making methods

Leprosy, also known as Hansen's, is one of the listed neglected tropical diseases as a major health problem global. Treatment is one of the main alternatives, however, the scarcity of medication and its poor distribution are important factors that have driven the spread of the disease, leading to irreversible and multi-resistant complications. This paper uses a distribution methodology to optimize medication administration, taking into account the most relevant attributes for the epidemiological profile of patients and the deficit in treatment via Polychemotherapy. Multi-criteria Decision Methods were applied based on AHP-Electre model in a database with information from patients in the state of Para between 2015 and 2020. The results pointed out that 84% of individuals did not receive any treatment and, among these, the method obtained a gain in the distribution of 68% in patients with positive diagnosis for leprosy.

Lead absorption capacity in different parts of plants and its influencing factors: a systematic review and meta-analysis

People pose a serious risk by plants contaminated with lead in soil. However, the strength of lead enrichment capacity in root, stem, and leaf of the plant is still controversial. Therefore, a meta-analysis was conducted to investigate the ability of lead enrichment of root, stem, and leaf and the main influencing factors for lead absorption. The results of this study indicated that all parts of plant can significantly accumulate lead. Concentrations of lead followed an order of root > stem > leaf. Alkaline soil was conducive to the absorption of lead. When the lead concentration in the soil was higher than 20 mg/kg, the lead absorption in root was more. Lead is absorbed most in trees and least in Gramineae. It is argued that this study is beneficial to select plants suitable for absorption of lead from polluted soil. This study also can help to clarify the influencing factors for lead enrichment in different parts of the plant.

Clinicopathological manifestations of coexistent monoclonal immunoglobulin deposition disease and immunotactoid glomerulopathy

Combination of monoclonal immunoglobulin deposition disease (MIDD) and immunotactoid glomerulopathy (ITG) is a rare form of monoclonal immunoglobulin (MIg)-associated renal disease. We retrospectively reviewed the native kidney biopsy specimens at Peking University People’s Hospital from 2011 to 2020. Five patients were diagnosed as MIDD + ITG. Their clinical and pathological characteristics were studied. The typical clinical features were nephritic syndrome and renal dysfunction with prominent anemia, but hematuria was mild. Unlike single MIDD and single ITG, on light microscopy, segmentally distributed mesangial nodular sclerosis on the basis of mesangial matrix hyperplasia was the major lesion. Others including membranoproliferative glomerulonephritis (MPGN)-like lesion, glomerular basement membrane thickness, and mild to moderate mesangial and endothelial proliferations might presented at the same time and in the same glomeruli. On immunofluorescence, MIg, usually monoclonal light chains, deposited along glomerular basement membranes and tubular basement membranes, while the intact MIg or monoclonal heavy chain deposited in the mesangial regions. Corresponding to the depositions on immunofluorescence, punctate “powdery” deposits along glomerular basement membranes and tubular basement membranes under electronic microscopy indicated the presence of MIDD. Microtubular substructures (diameters of 20–50 nm) exhibiting hollow cores arranged in parallel arrays in mesangial regions indicated the presence of ITG. Patients treated with bortezomib-based regimen seemed to have better outcomes. In conclusion, MIDD + ITG is a rare combination form of MIg-associated renal disease. Accurate diagnosis requires the comprehensive pathological investigations.

Piezo1 promoted hepatocellular carcinoma progression and EMT through activating TGF-β signaling by recruiting Rab5c

BACKGROUND

Piezo1 has been revealed to play a regulatory role in vascular development and progression of variety tumors. However, whether and how the progression of hepatocellular carcinoma (HCC) regulated by Piezo1 remains elusive. This study aimed to elucidate the effect and mechanisms of Piezo1 in HCC.

METHODS

The mRNA and protein expression level of Piezo1 in HCC samples and cell lines was determined by qRT-PCR, western blot and immunohistochemistry analyses. Two independent study cohorts containing 280 patients were analyzed to reveal the association between Piezo1 expression and clinicopathological characteristics. Series of in vitro and in vivo experiments were used to validate the function of Piezo1 in HCC. Gene set enrichment analysis (GSEA) was performed to explore the signaling pathway of Piezo1. Immunoprecipitation, immunofluorescence and in vitro and in vivo experiments were used to explore the molecular mechanism of Piezo1 in HCC progression.

RESULTS

Our results demonstrated the Piezo1 expression was significantly upregulated in HCC tissues and cell lines, and upregulation of Piezo1 closely correlated with aggressive clinicopathological features and poor prognosis. Knockdown of Piezo1 in HCCLM3 and Hep3B cells significantly restrained proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of HCC cells in vitro, and tumor growth, metastasis, EMT in vivo. TGF-β signaling pathway was most significant enriched pathway in GSEA. Finally, tumor promotion effect of Piezo1 was found to exerted through recruiting and combining Rab5c to activating TGF-β signaling pathway.

CONCLUSIONS

Piezo1 significantly related to poor prognosis and promotes progression of hepatocellular carcinoma via activating TGF-β signaling, which suggesting that Piezo1 may serve as a novel prognostic predictor and the potential therapeutic target for HCC patients.

Integrative QTL Identification, Fine Mapping and Candidate Gene Analysis of a Major Locus qLTG3a for Seed Low-Temperature Germinability in Rice

Low-temperature germinability (LTG) is an important agronomic trait that can affect the planting time, planting area, and grain yield of staple crops, such as rice. However, the genetic mechanism of LTG is still unclear. In this study, a multi-parental permanent population with 208 single segment substitution lines (SSSLs) was used to conduct a genetic dissection for LTG across four cropping seasons. LTG was a typical quantitative trait with a high combined broad-sense heritability of 0.71. By comparison with the recipient parent, Huajingxian74, 24 SSSLs were identified as carrying LTG QTLs, which were further merged into integrated QTLs with shorter genetic distances by substitution mapping. Finally, 14 LTG QTLs were mapped on ten chromosomes, including seven positive-effect and seven negative-effect QTLs, with additive effect contributions ranging from 19.2 to 39.9%. qLTG3a, a main-effect and novel QTL, was confirmed by bulk segregant analysis using an F₂ segregating population, and five key recombinants were selected to develop F₃ populations for progeny testing. Marker-trait association analysis fine mapped qLTG3a to a 332.7-kb physical region between markers M6026 and M6341. Within this interval, 40 annotated genes were revealed, and three genes (Os03g0213300, Os03g0214400, and Os03g0214600) were considered as pivotal candidate genes for qLTG3a based on their sequence variations and expression patterns. Besides low temperature, qLTG3a can also enhance seed germination under standard temperature and osmotic stress. In summary, this study identified some genetic factors regulating LTG and opened a new window for breeding elite direct-seeded rice varieties. It will help reduce the climate risk in the production process of rice, which is of great significance to ensuring food security.

Structural and spectral properties of a non-classical C58 isomer and its fluorinated derivatives in theory

The traditional classical fullerene is only composed of pentagons and hexagons, with many different topologies, of which only a few structures conform to the isolated pentagon rule (IPR), which means all five-membered rings are separated by hexagons, whereas isomers that violate the rule are called non-IPR isomers. In contrast, the non-classical fullerene consists of other kinds of polygons such as squares and heptagons in addition to pentagons and hexagons. X-ray photoelectron spectra (XPS), near-edge X-ray absorption fine structure (NEXAFS) spectra and X-ray emission spectra (XES), as well as the ground-state electronic/geometrical structures of the important non-IPR isomers C 3v-#1205C58 and C 2-#1078C58, and the remarkable non-classical isomer C s-C58(NC) with its two fluorides C s-C58(NC)F18(A) and C s-C58(NC)F18(B), have been computed at the density functional theory (DFT) level. Significant differences in the electronic structures and simulated X-ray spectra have been observed after fluorination. Meanwhile, strong isomer dependence has been shown in these spectra, which means the "fingerprint" in the X-ray spectra can effectively identify the above-mentioned fullerene isomers. As a consequence, the work can provide useful information especially isomer identification for experimental and theoretical research in fullerene science.

Upregulation of microRNA-451 attenuates myocardial I/R injury by suppressing HMGB1

Both MicroRNAs and HMGB1 took part in pathological process of myocardial I/R injury though several signaling pathways. We hypothesized that mircoRNA451 (miR-451), a group of small non-coding RNAs, could improve this injury by inhibiting HMGB1. Male SD rats were randomly distributed into 5 groups and subjected to I/R process. After 24 hours of reperfusion injury, the serum content of CK and LDH, the content of MDA in tissue and activity of SOD were detected; The infarcted areas were defined by TTC staining and Evans Blue; TUNEL staining and cleaved-Caspase 3 were used to test apoptosis; HMGB1 was detected by real-time fluorescence quantitative PCR and Western Blotting. Compared with the I/R and I/R+Ad-GFP group, upregulation of miR-451 could reduce the infarcted areas, cardiomyocytes apoptosis index, expression of cleaved-caspase 3 and content of CK and LDH significantly(P<0.05); Meanwhile, upregulation of miR-451 could also obviously inhibit HMGB1, the increase of MDA and the decrease of SOD (P<0.05). So this study revealed that upregulation of miR-451 could prevent myocardial I/R injury by suppressing HMGB1.

Polyoxometalate-based electron transfer modulation for efficient electrocatalytic carbon dioxide reduction

The electrocatalytic carbon dioxide (CO2) reduction reaction (CO2RR) involves a variety of electron transfer pathways, resulting in poor reaction selectivity, limiting its use to meet future energy requirements. Polyoxometalates (POMs) can both store and release multiple electrons in the electrochemical process, and this is expected to be an ideal "electron switch" to match with catalytically active species, realize electron transfer modulation and promote the activity and selectivity of the electrocatalytic CO2RR. Herein, we report a series of new POM-based manganese-carbonyl (MnL) composite CO2 reduction electrocatalysts, whereby SiW12-MnL exhibits the most remarkable activity and selectivity for CO2RR to CO, resulting in an increase in the faradaic efficiency (FE) from 65% (MnL) to a record-value of 95% in aqueous electrolyte. A series of control electrochemical experiments, photoluminescence spectroscopy (PL), transient photovoltage (TPV) experiments, and density functional theory (DFT) calculations revealed that POMs act as electronic regulators to control the electron transfer process from POM to MnL units during the electrochemical reaction, enhancing the selectivity of the CO2RR to CO and depressing the competitive hydrogen evolution reaction (HER). This work demonstrates the significance of electron transfer modulation in the CO2RR and suggests a new idea for the design of efficient electrocatalysts towards CO2RR.

Impact of Milk Fortification on the Microbiological and Physicochemical Properties of Set-Type Skimmed Yoghurt Using Three Commercial Soluble Prebiotics

The impact of milk fortification on the microbiological and physicochemical properties of a set-type skimmed yoghurt using three commercial soluble prebiotics (inulin, iso-malto-oligosaccharides, and xylo-oligosaccharides) at either 3 or 5 g/kg was assessed. The three prebiotics had an insignificant impact on yoghurt fermentation because all yoghurt samples had similar titratable acidity and similar pH values after their lactic acid fermentation. Regarding the control yoghurt samples without prebiotics usage, the prebiotics-fortified yoghurt samples showed no difference in their main chemical compositions, hardness, syneresis extent, and apparent viscosity (p > 0.05), but had a slightly higher lactic acid content and a viable quantity of starter strains. All yoghurt samples had the same acetic acid content, while propionic and butyric acids were not produced. Yoghurt storage at 4 C for 21 d gave these yoghurt samples decreased pH values and a viable quantity of starter strains (especially Lactobacillus delbrueckii subsp. bulgaricus) and unchanged acetic acid; however, it increased lactic acid contents. Overall, prebiotics fortification up to 5 g/kg had a completely insignificant impact on the fermentation and quality attributes of yoghurt samples but could possibly improve the health of consumers due to higher dietary fibers and starter strain populations.

Investigation on the correlation between energy deposition and clustered DNA damage induced by low-energy electrons

This study presents the correlation between energy deposition and clustered DNA damage, based on a Monte Carlo simulation of the spectrum of direct DNA damage induced by low-energy electrons including the dissociative electron attachment. Clustered DNA damage is classified as simple and complex in terms of the combination of single-strand breaks (SSBs) or double-strand breaks (DSBs) and adjacent base damage (BD). The results show that the energy depositions associated with about 90% of total clustered DNA damage are below 150 eV. The simple clustered DNA damage, which is constituted of the combination of SSBs and adjacent BD, is dominant, accounting for 90% of all clustered DNA damage, and the spectra of the energy depositions correlating with them are similar for different primary energies. One type of simple clustered DNA damage is the combination of a SSB and 1-5 BD, which is denoted as SSB + BD. The average contribution of SSB + BD to total simple clustered DNA damage reaches up to about 84% for the considered primary energies. In all forms of SSB + BD, the SSB + BD including only one base damage is dominant (above 80%). In addition, for the considered primary energies, there is no obvious difference between the average energy depositions for a fixed complexity of SSB + BD determined by the number of base damage, but average energy depositions increase with the complexity of SSB + BD. In the complex clustered DNA damage constituted by the combination of DSBs and BD around them, a relatively simple type is a DSB combining adjacent BD, marked as DSB + BD, and it is of substantial contribution (on average up to about 82%). The spectrum of DSB + BD is given mainly by the DSB in combination with different numbers of base damage, from 1 to 5. For the considered primary energies, the DSB combined with only one base damage contributes about 83% of total DSB + BD, and the average energy deposition is about 106 eV. However, the energy deposition increases with the complexity of clustered DNA damage, and therefore, the clustered DNA damage with high complexity still needs to be considered in the study of radiation biological effects, in spite of their small contributions to all clustered DNA damage.

Efficacy of fluorides and CPP-ACP vs fluorides monotherapy on early caries lesions: A systematic review and meta-analysis

The study aimed to evaluate the efficacy of the combination of CPP-ACP and fluorides compared with fluorides monotherapy on patients with early caries lesions. The Medline, Embase and Cochrane databases up to August 2017 were scanned, with no restrictions. Studies satisfied the guideline of randomised controlled trials (RCTs), the patients with early caries lesions and data considering the efficacy of fluorides and CPP-ACP versus fluorides alone were selected. There was no language restriction during the literature search process, however, only papers in English or Chinese were included during the selection process. Outcome variables include laser fluorescence, quantitative light-induced fluorescence, lesion area and visual inspection scores. Mean differences were calculated during the data extraction process. Ten studies including 559 patients were selected in the meta-analysis. Fluorides combined with CPP-ACP achieved the same efficacy for early caries lesions on smooth surfaces compared with fluorides monotherapy (mean difference: -13.90, 95% confidence interval: [-39.25, 11.46], P = 0.28), and the combination treatment showed significantly better efficacy than fluorides monotherapy for occlusal early caries lesions (mean difference: -21.02, 95% confidence interval: [-27.94, -14.10], P<0.01). However, further well-designed studies are still needed.

Engineering the Complex-Valued Constitutive Parameters of Metamaterials for Perfect Absorption

We theoretically studied how to directly engineer the constitutive parameters of metamaterials for perfect absorbers of electromagnetic waves. As an example, we numerically investigated the necessary refractive index n and extinction coefficient k and the relative permittivity ε and permeability μ of a metamaterial anti-reflection layer, which could cancel the reflection from a hydrogenated amorphous silicon (α-Si:H) thin film on a metal substrate, within the visible wavelength range from 300 to 800 nm. We found that the metamaterial anti-reflection layer should have a negative refractive index (n < 0) for short-wavelength visible light but have a positive refractive index (n > 0) for long-wavelength visible light. The relative permittivity ε and permeability μ could be fitted by the Lorentz model, which exhibited electric and magnetic resonances, respectively.

Prebiotic Synthesis of Glycine from Ethanolamine in Simulated Archean Alkaline Hydrothermal Vents

Submarine hydrothermal vents are generally considered as the likely habitats for the origin and evolution of early life on Earth. In recent years, a novel hydrothermal system in Archean subseafloor has been proposed. In this model, highly alkaline and high temperature hydrothermal fluids were generated in basalt-hosted hydrothermal vents, where H2 and CO2 could be abundantly provided. These extreme conditions could have played an irreplaceable role in the early evolution of life. Nevertheless, sufficient information has not yet been obtained for the abiotic synthesis of amino acids, which are indispensable components of life, at high temperature and alkaline condition. This study aims to propose a new method for the synthesis of glycine in simulated Archean submarine alkaline vent systems. We investigated the formation of glycine from ethanolamine under conditions of high temperature (80-160 °C) and highly alkaline solutions (pH = 9.70). Experiments were performed in an anaerobic environment under mild pressure (0.1-8.0 MPa) at the same time. The results suggested that the formation of glycine from ethanolamine occurred rapidly and efficiently in the presence of metal powders, and was favored by high temperatures and high pressures. The experiment provides a new pathway for prebiotic glycine formation and points out the phenomenal influence of high-temperature alkaline hydrothermal vents in origin of life in the early ocean.

Saccharomyces boulardii and Bacillus subtilis B10 modulate TLRs and cytokines expression patterns in jejunum and ileum of broilers

The present study was designed to evaluate the effects of Saccharomyces boulardii (Sb) and Bacillus subtilis B10 (Bs) on intestinal epithelial Toll like receptors (TLR), and Cytokine expression response to understand the intestinal epithelial innate immune mechanism in broilers. A total of 300 birds (Sanhuang broilers) were allotted into three groups (n = 100) and each divided into five replications (n = 20). Control group (Ctr) birds were fed basal diet, broilers in experimental groups received (1×108cfu/kg feed) Sb and Bs respectively in addition to basal diet for 72 days. The result showed significant increase in mRNA expression level of TLR2, TLR4 and TLR15. Down streaming MyD88, TRAF6, TAB2 and NF-κB mRNA level noted higher, in the jejunum and ileum as compared to control group. Meanwhile, IL-6, TNFα, IL-10, TGF-β expression levels showed high expression in the jejunum of Sb and Bs groups. IL-10 expression level increased in the ileum and IL-6, TNFα, IL-10 and TGF-β expression levels increased in the jejunum of Sb group. Levels of IL-1 β, IL-17, and IL-4, increased merely in Sb group. Ileal cytokines IL-1β, IL-17 and IL-4concentration were noted higher in Sb group, and IL-1β, and IL-4 levels were up-regulated in Bs group. The results indicated that the INF-γ and IL-8 level decreased in Sb and BS groups. Serum IgA and sIgA level increased in both treatment groups. Our findings illustrated that S. boulardii and B. subtilis B10 may have a role to induce mucosal immunity by activating the TLRs and cytokines expressions in broilers.

BnaABF2, a bZIP transcription factor from rapeseed (Brassica napus L.), enhances drought and salt tolerance in transgenic Arabidopsis

BACKGROUND

Abiotic stresses such as drought and salt stresses have a negative effect on the growth and productivity of plants. Improvement of stress tolerance through genetic engineering in plants has been reported in intense studies. Transcription factors play vital roles in plant adaptation to stresses by regulating expression of a great deal of target genes. A family of Arabidopsis basic region leucine zipper (bZIP) transcription factors that can recognize and bind to the abscisic acid (ABA)-responsive elements (ABREs) in promoter is named as ABRE binding factors (ABFs)/ABRE binding proteins (AREBs). They play a key role in the regulation of expression of downstream stress-responsive genes in ABA signalling. Genetic transformation of ABF/ABRE transcription factors has been suggested to be an effective approach for engineering stress-tolerant plants. However, whether the ABF/ABRE transcription factors are able to be used for generating stress-tolerant rapeseed plants has not yet been studied.

RESULTS

BnaABF2, encoding a bZIP transcription factor, was cloned from rapeseed in this study. Subcellular localization and transactivation analyses showed that BnaABF2 was localized to the nucleus with transactivation activity in plant cells. BnaABF2 gene expression was induced by drought and salt stresses and BnaABF2 positively functions in ABA signalling during the vegetative stage. Overexpression of BnaABF2 was found to render drought and salt tolerance to Arabidopsis plants. The resistance of the BnaABF2-expressing transgenic plants to drought and salt stresses is due to reduced water-loss rate and expression of stress-responsive genes such as RD29B, RAB18 and KIN2. The expression of RD29B, RAB18 and KIN2 regulated by BnaABF2 is involved in an ABA-dependent stress signalling.

CONCLUSIONS

Identification of the positive role of rapeseed BnaABF2 in plant tolerance to drought and salt provides evidence for ability of engineering stress-tolerant rapeseed plants by genetic transformation of BnaABF2.

Liquid Crystalline Nanoparticles as an Ophthalmic Delivery System for Tetrandrine: Development, Characterization, and In Vitro and In Vivo Evaluation

The purpose of this study was to develop novel liquid crystalline nanoparticles (LCNPs) that display improved pre-ocular residence time and ocular bioavailability and that can be used as an ophthalmic delivery system for tetrandrine (TET). The delivery system consisted of three primary components, including glyceryl monoolein, poloxamer 407, and water, and two secondary components, including Gelucire 44/14 and amphipathic octadecyl-quaternized carboxymethyl chitosan. The amount of TET, the amount of glyceryl monoolein, and the ratio of poloxamer 407 to glyceryl monoolein were selected as the factors that were used to optimize the dependent variables, which included encapsulation efficiency and drug loading. A three-factor, five-level central composite design was constructed to optimize the formulation. TET-loaded LCNPs (TET-LCNPs) were characterized to determine their particle size, zeta potential, entrapment efficiency, drug loading capacity, particle morphology, inner crystalline structure, and in vitro drug release profile. Corneal permeation in excised rabbit corneas was evaluated. Pre-ocular retention was determined using a noninvasive fluorescence imaging system. Finally, pharmacokinetic study in the aqueous humor was performed by microdialysis technique. The optimal formulation had a mean particle size of 170.0 ± 13.34 nm, a homogeneous distribution with polydispersity index of 0.166 ± 0.02, a positive surface charge with a zeta potential of 29.3 ± 1.25 mV, a high entrapment efficiency of 95.46 ± 4.13 %, and a drug loading rate of 1.63 ± 0.07 %. Transmission electron microscopy showed spherical particles that had smooth surfaces. Small-angle X-ray scattering profiles revealed an inverted hexagonal phase. The in vitro release assays showed a sustained drug release profile. A corneal permeation study showed that the apparent permeability coefficient of the optimal formulation was 2.03-fold higher than that of the TET solution. Pre-ocular retention capacity study indicated that the retention of LCNPs was significantly longer than that of the solution (p < 0.01). In addition, a pharmacokinetic study of rabbit aqueous humors demonstrated that the TET-LCNPs showed 2.65-fold higher ocular bioavailability than that of TET solution. In conclusion, a LCNP system could be a promising method for increasing the ocular bioavailability of TET by enhancing its retention time and permeation into the cornea.

Isoprenylated Flavonoids with PTP1B Inhibition from Macaranga denticulata

Three new C-methylated and isoprenylated chalcone derivatives, dentichalcones A-C (1-3), together with six known compounds (4-9), were isolated from the twigs and leaves of Macaranga denticulata. Their structures were elucidated by spectroscopic analysis, including 1D, 2D NMR, and MS data. The known compounds, (2E)-1-(5,7-dihydroxy-2,2,6-trimethyl-2H-benzopyran-8-yl)-3-(4-methoxyphenyl)-2-propen-1-one (4), (2E)-1-(5,7-dihydroxy-2,2-dimethyl-2H-benzopyran-8-yl)-3-phenyl-2-propen-1-one (5), laxichalcone (6), macarangin (7), bonanniol A (8), and bonannione A (9), showed inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) in vitro. Three new C-methylated and isoprenylated chalcone derivatives, dentichalcones A-C (1-3), together with six known compounds, were isolated from the twigs and leaves of Macaranga denticulata. Some compounds showed inhibitory activities against PTP1B in vitro.