Mapping and validation of a novel major QTL for resistance to stripe rust in four wheat populations derived from landrace Qishanmai

Wheat yield has been constrained by stripe rust disease globally. A wheat landrace (Qishanmai, QSM) consistently showed lower stripe rust severities in multiple year studies than susceptible check varieties including Suwon11 (SW) at the adult plant stage. To detect QTL for reducing the severity in QSM, 1218 recombinant inbred lines (RILs) were developed from SW × QSM. QTL detection was conducted firstly using 112 RILs selected for similarity in pheno-morphological characters. The 112 RILs were assessed for stripe rust severity at the 2nd leaf, 6th leaf and flag leaf stages under field and greenhouse conditions, and genotyping was done primarily with a single nucleotide polymorphism (SNP) array. On the basis of these phenotypic and genotypic data, a major QTL (QYr.cau-1DL) was detected on chromosome 1D at the 6th leaf and flag leaf stages. Further mapping was conducted by genotyping 1218 RILs using new simple sequence repeat (SSR) markers, which were developed by referring to the sequences of the wheat line Chinese Spring (IWGSC RefSeq v1.0). QYr.cau-1DL was mapped within a 0.5 cM (5.2 Mb) interval delimited by the SSR markers 1D-320.58 and 1D-325.79. These markers were applied to select for QYr.cau-1DL by screening F2 or BC4F2 plants of the wheat crosses RL6058 × QSM, Lantian10 × QSM and Yannong21 × QSM. F2:3 or BC4F2:3 families derived from the selected plants were assessed for stripe rust resistance in the fields of two locations and in a greenhouse. Wheat plants carrying the resistant marker haplotype in homozygous state for QYr.cau-1DL showed lower stripe rust severities (by 44% to 48%) than plants lacking this QTL. The trial of RL6058 (a carrier of Yr18) × QSM also indicated that QYr.cau-1DL had larger effect than Yr18 on reducing severity; they acted synergistically, yielding an elevated level of stripe rust resistance

Myeloid deletion of phosphoinositide-dependent kinase-1 enhances NK cell-mediated antitumor immunity by mediating macrophage polarization

A large number of heterogeneous macrophages can be observed in solid tumor lesions. Classically activated M1 macrophages are a powerful killer of cancer cells. In contrast, tumor-associated macrophages (TAMs) are often referred to as M2 phenotype and usually impair tumor immunity mediated by cytotoxic lymphocytes, natural killer (NK) cells and CD8+ T cells. Therefore, orchestrating M2 to M1 reprogramming will provide a promising approach to tumor immunotherapy. Here we used a PyMT-induced spontaneous breast cancer model in which M2-polarized macrophages were abundant. This M2 phenotype was closely related to tumor progression and immune dysfunction of NK cells and CD8+ T cells. We then found that these TAMs showed increased energy expenditure and over-activation of two kinases, Akt and mammalian target of rapamycin (mTOR). Myeloid inactivation of phosphoinositide-dependent kinase-1 (PDK1), the upstream regulator for Akt and mTOR signaling, significantly reduced excessive metabolic activation of macrophages. Notably, the loss of PDK1 significantly led to regression of breast cancer and prevented lung metastasis. Mechanistically, PDK1 deficiency mainly inhibited the activation of mTOR complex 1 (mTORC1), transforming TAMs into M1 phenotype, thereby reversing tumor-related dysfunction of T cells and NK cells. Therefore, targeting PDK1 may be a new approach for M2 macrophage-enriched solid tumor immunotherapy

A Novel Wideband Transition from LTCC Laminated Waveguide to Air-Filled Rectangular Waveguide for W-band Applications

In this paper, a novel wideband transition from a laminated waveguide (LWG) to an air-filled rectangular waveguide (RWG) is proposed for millimeter-wave integration solutions based on multilayer low-temperature co-fired ceramic (LTCC) technology. The integrated transition cavity is divided into several resonators by introducing five grounded via holes. Due to the magnetic wall existing in the symmetry plane, the equivalent circuit of the proposed transition can be simplified as a three-pole filter model to explain the working mechanism with wideband performance. A W-band integrated LWG-to-RWG transition is designed as an example using LTCC technology. Two back-to-back prototypes with different lengths are fabricated and measured. A measured 25.7% bandwidth from 76 GHz to 101 GHz can be achieved for return loss better than 14 dB. The average insertion loss of a single transition is about 0.5 dB. The compact structure and wideband performance give it potential in high-density millimeter-wave and terahertz packaging

Lead-induced cardiomyocytes apoptosis by inhibiting gap junction intercellular communication via autophagy activation

Lead (Pb) is one of the most common heavy metal contaminants in the environment. Pb can cause pathophysiological changes in several organ systems, including the cardiovascular system, but the molecular mechanism remains elusive. The study aimed to study the effects of Pb on Gap junction intercellular communication (GJIC) and its role in Pb-induced apoptosis. The present study aims to determine whether Pb-induced autophagy promotes apoptosis of rat cardiac myocytes (H9c2\ua0cells) by downregulating GJIC using CCK-8 Kit, scrape loading/dye transfer assay, Annexin V/PI assays, Western blot analysis and double-immunofluorescence experiments. The results showed that Pb elicited cytotoxicity in a time- and concentration-dependent manner and led to increased apoptosis in a concentration-dependent manner in\ua0H9c2\ua0cells. Pb also reduced GJIC in\ua0H9c2\ua0cells in a concentration-dependent manner through the downregulation of connexin (Cx) 43. Inhibition of gap junctions by gap junction blocker carbenoxolone disodium (CBX) resulted in increased apoptosis. Furthermore, Pb increased autophagy in a concentration-dependent manner in\ua0H9c2\ua0cells, promoting the internalization of Cx43 and targeting the autophagosome via light chain 3 (LC3). However, autophagy inhibitor 3-Methyladenine (3-MA) can slow down the downregulation of Cx43 induced by Pb in\ua0H9c2\ua0cells. In conclusion, our results provide that Pb-decreased GJIC promotes apoptosis in cardiomyocytes. It is probably because Pb-induced autophagy exacerbates GJIC inhibition and downregulation of Cx43. These results suggest that GJIC plays a protective role in Pb-induced apoptosis in rat cardiomyocytes, and GJIC may be one of the targets of Pb-induced biological effects

QTL mapping of wheat plant architectural characteristics and their genetic relationship with seven QTLs conferring resistance to sheath blight

<div><p>Sheath blight is one of the most devastating wheat diseases worldwide. Breeding resistant cultivars is the most powerful strategy to defeat the disease. Plant resistance on “disease escape” works through modulation of morphological traits and shows sustainable resistance to disease. Plant architectural traits have been reported to play a significant role in disease response. Therefore, exploring the genetic relationship between plant architecture and disease resistance is of importance to the understanding of plant resistance via “disease escape”. Using an F₉ population of 266 RILs (Recombinant Inbred Lines) derived from the cross of Luke × AQ24788-83, we have generated a linkage map of 631 markers on 21 chromosomes. In this study, we present the QTL identification of fourteen plant architectural characteristics and heading time from two years and analyze their genetic relationships with seven previously published QTLs to sheath blight (QSBs, <i>QSe</i>.<i>cau</i>), including plant height (PH), the space between the flag leaf and penultimate leaf (fdR), heading date (Hd), and other traits. Twelve stable QTLs of the morphological traits were identified with good consistency across five replicates. For the seven previously published QSBs, we found no significant association with plant height. However, some of the QSBs displayed strong associations with plant architectural traits and heading date. Especially, <i>Q</i>_<i>fdR</i>.<i>cau-1AS</i>, <i>Q</i>_<i>Hd</i>.<i>cau-2BS</i>, <i>Q</i>_<i>fdR</i>.<i>cau-5DL</i>, and <i>Q</i>_<i>fdR</i>.<i>cau-6BL</i> were respectively mapped to the same regions as <i>QSe</i>.<i>cau-1AS</i>, <i>QSe</i>.<i>cau-2BS</i>, <i>QSe</i>.<i>cau-5DL</i>, and <i>QSe</i>.<i>cau-6BL</i>. Taken together, we have demonstrated that plant height did not exert a direct influence on the resistance to sheath blight conferred by the seven QSBs and that the plant architecture and heading date did exhibit a tight relationship with the resistance. Therefore, this study provides a novel evidence to help understand sheath blight resistance in wheat. In addition, the linked morphological characteristics and the generated flanking markers will facilitate breeding for resistance to sheath blight in wheat.</p></div

Understanding the mechanisms of silica nanoparticles for nanomedicine

As a consequence of recent progression in biomedicine and nanotechnology, nanomedicine has emerged rapidly as a new discipline with extensive application of nanomaterials in biology, medicine, and pharmacology. Among the various nanomaterials, silica nanoparticles (SNPs) are particularly promising in nanomedicine applications due to their large specific surface area, adjustable pore size, facile surface modification, and excellent biocompatibility. This paper reviews the synthesis of SNPs and their recent usage in drug delivery, biomedical imaging, photodynamic and photothermal therapy, and other applications. In addition, the possible adverse effects of SNPs in nanomedicine applications are reviewed from reported in vitro and in vivo studies. Finally, the potential opportunities and challenges for the future use of SNPs are discussed. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies

The Cotransplantation of Olfactory Ensheathing Cells with Bone Marrow Mesenchymal Stem Cells Exerts Antiapoptotic Effects in Adult Rats after Spinal Cord Injury

The mechanisms behind the repairing effects of the cotransplantation of olfactory ensheathing cells (OECs) with bone marrow mesenchymal stromal cells (BMSCs) have not been fully understood. Therefore, we investigated the effects of the cotransplantation of OECs with BMSCs on antiapoptotic effects in adult rats for which the models of SCI are induced. We examined the changes in body weight, histopathological changes, apoptosis, and the expressions of apoptosis-related proteins after 14 days and 28 days after transplantation. We also assessed animal locomotion using BBB test. We found that treatment with OECs and BMSCs had a remissive effect on behavioral outcome and histopathological changes induced SCI. Furthermore, we observed the significant antiapoptotic effect on cotransplant treated group. In addition, cotransplantation of OECs with BMSCs was found to have more significant repairing effect than that of OECs or BMSCs alone. Furthermore, the recovery of hind limb could be related to antiapoptotic effect of OECs and BMSCs through downregulating the apoptotic pathways. Finally, our data suggested the cotransplantation of OECs with BMSCs holds promise for a potential cure after SCI through the ability to incorporate into the spinal cord