ABSTRACT
FMS-related tyrosine kinase 3 ligand (FLT3L), encoded by FLT3LG, is a hematopoietic factor essential for the development of natural killer (NK) cells, B cells, and dendritic cells (DCs) in mice. We describe three humans homozygous for a loss-of-function FLT3LG variant with a history of various recurrent infections, including severe cutaneous warts. The patients' bone marrow (BM) was hypoplastic, with low levels of hematopoietic progenitors, particularly myeloid and B cell precursors. Counts of B cells, monocytes, and DCs were low in the patients' blood, whereas the other blood subsets, including NK cells, were affected only moderately, if at all. The patients had normal counts of Langerhans cells (LCs) and dermal macrophages in the skin but lacked dermal DCs. Thus, FLT3L is required for B cell and DC development in mice and humans. However, unlike its murine counterpart, human FLT3L is required for the development of monocytes but not NK cells.
Subject(s)
Killer Cells, Natural , Membrane Proteins , Animals , Female , Humans , Male , Mice , B-Lymphocytes/metabolism , B-Lymphocytes/cytology , Bone Marrow/metabolism , Cell Lineage , Dendritic Cells/metabolism , Hematopoiesis , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/cytology , Killer Cells, Natural/metabolism , Killer Cells, Natural/immunology , Langerhans Cells/metabolism , Membrane Proteins/metabolism , Membrane Proteins/genetics , Monocytes/metabolism , Skin/metabolism , Mice, Inbred C57BLABSTRACT
A simple, reliable method for identifying ß-lactoglobulin (ß-LG) in dairy products is needed to protect those with ß-LG allergies. A common, practical strategy for target detection is designing simplified nucleic acid nanodevices by integrating functional components. This work presents a label-free modular ß-LG aptasensor consisting of an aptamer-loop G-quadruplex (G4), the working conformation of which is regulated by conformational antagonism to ensure respective module functionality and the related signal transduction. The polymorphic conformations of the module-fused sequence are systematically characterized, and the cause is revealed as shifting antagonistic equilibrium. Combined with conformational folding dynamics, this helped regulate functional conformations by fine-tuning the sequences. Furthermore, the principle of specific ß-LG detection by parallel G4 topology is examined as binding on the G4 aptamer loop by ß-LG to reinforce the G4 topology and fluorescence. Finally, a label-free, assembly-free, succinct, and turn-on fluorescent aptasensor is established, achieving excellent sensitivity across five orders of magnitude, rapidly detecting ß-LG within 22-min. This study provides a generalizable approach for the conformational regulation of module-fused G4 sequences and a reference model for creating simplified sensing devices for a variety of targets.
Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , G-Quadruplexes , Lactoglobulins , Lactoglobulins/chemistry , Aptamers, Nucleotide/chemistry , Biosensing Techniques/methodsABSTRACT
Corn leaf aphids (Rhopalosiphum maidis) are highly destructive pests of maize (Zea mays) that threaten growth and seed yield, but resources for aphid resistance are scarce. Here, we identified an aphid-resistant maize mutant, resistance to aphids 1 (rta1), which is allelic to LIGULELESS1 (LG1). We confirmed LG1's role in aphid resistance using the independent allele lg1-2, allelism tests and LG1 overexpression lines. LG1 interacts with, and increases the stability of ZINC-FINGER PROTEIN EXPRESSED IN INFLORESCENCE MERISTEM (ZIM1), a central component of the jasmonic acid (JA) signalling pathway, by disturbing its interaction with the F-box protein CORONATINE INSENSITIVE 1a (COI1a). Natural variation in the LG1 promoter was associated with aphid resistance among inbred lines. Moreover, a loss-of-function mutant in the LG1-related gene SPL8 in the dicot Arabidopsis thaliana conferred aphid resistance. This study revealed the aphid resistance mechanism of lg1, providing a theoretical basis and germplasm for breeding aphid-resistant crops.
ABSTRACT
AIMS: Limb-girdle congenital myasthenic syndrome (LG-CMS) is a genetically heterogeneous disorder characterized by muscle weakness and fatigability. The LG-CMS gene DPAGT1 codes for an essential enzyme of the glycosylation pathway, a posttranslational modification mechanism shaping the structure and function of proteins. In DPAGT1-related LG-CMS, reduced glycosylation of the acetylcholine receptor (AChR) reduces its localization at the neuromuscular junction (NMJ), and results in diminished neuromuscular transmission. LG-CMS patients also show tubular aggregates on muscle biopsy, but the origin and potential contribution of the aggregates to disease development are not understood. Here, we describe two LG-CMS patients with the aim of providing a molecular diagnosis and to shed light on the pathways implicated in tubular aggregate formation. METHODS: Following clinical examination of the patients, we performed next-generation sequencing (NGS) to identify the genetic causes, analysed the biopsies at the histological and ultrastructural levels, investigated the composition of the tubular aggregates, and performed experiments on protein glycosylation. RESULTS: We identified novel pathogenic DPAGT1 variants in both patients, and pyridostigmine treatment quantitatively improved muscle force and function. The tubular aggregates contained proteins of the sarcoplasmic reticulum (SR) and structurally conformed to the aggregates observed in tubular aggregate myopathy (TAM). TAM arises from overactivation of the plasma membrane calcium channel ORAI1, and functional studies on muscle extracts from our LG-CMS patients evidenced abnormal ORAI1 glycosylation. CONCLUSIONS: We expand the genetic variant spectrum of LG-CMS and provide a genotype/phenotype correlation for pathogenic DPAGT1 variants. The discovery of ORAI1 hypoglycosylation in our patients highlights a physiopathological link between LG-CMS and TAM.
ABSTRACT
Regio- and stereo-selective hydroxylation of bile acids is a valuable reaction but often lacks suitable catalysts. In the research, semi-rational design in protein engineering techniques had been applied on cytochrome P450 monooxygenase CYP102A1 (P450 BM3) from Bacillus megaterium, and a mutation library had been set up for the 1ß-hydroxylation of lithocholic acid (LCA) to produce 1ß-OH-LCA. After four rounds of mutagenesis, a key residue at W72 was identified to regulate the regio- and stereo-selectivity at C1 of LCA. A quadruple variant (G87A/W72T/A74L/L181M) was identified to reach 99.4% selectivity of 1ß-hydroxylation and substrate conversion of 68.1% resulting in a 21.5-fold higher level of 1ß-OH-LCA production than the template LG-23. Molecular docking indicated that introducing hydrogen bonds at W72 was responsible for enhancing selectivity and catalytic activity, which gave some insights into the structure-based understanding of Csp3 -H activation by the developed P450 BM3 mutants.
Subject(s)
Bacillus megaterium , Lithocholic Acid , Molecular Docking Simulation , Hydroxylation , Lithocholic Acid/metabolism , NADPH-Ferrihemoprotein Reductase/chemistry , Bacterial Proteins/metabolism , Cytochrome P-450 Enzyme System/metabolism , Bacillus megaterium/geneticsABSTRACT
We previously reported associations between autoantibodies to the LG3 fragment of perlecan, anti-LG3, and a higher risk of delayed graft function (DGF) in kidney transplant recipients. Here, we aimed to determine whether some factors that modulate ischemia-reperfusion injury (IRI) can modify this association. We performed a retrospective cohort study in kidney transplant recipients in 2 university-affiliated centers. In 687 patients, we show that high pre-transplant anti-LG3 are associated with DGF when the kidney is transported on ice (odds ratio (OR): 1.75, 95% confidence interval 1.02-3.00), but not when placed on hypothermic perfusion pump (OR: 0.78, 95% CI 0.43-1.37). In patients with DGF, high pre-transplant anti-LG3 are associated with a higher risk of graft failure (subdistribution hazard ratio (SHR): 4.07, 95% CI: 1.80, 9.22), while this was not the case in patients with immediate graft function (SHR: 0.50, 95% CI 0.19, 1.29). High anti-LG3 levels are associated with a higher risk of DGF in kidneys exposed to cold storage, but not when hypothermic pump perfusion is used. High anti-LG3 are also associated with a higher risk of graft failure in patients who experience DGF, a clinical manifestation of severe IRI.
Subject(s)
Delayed Graft Function , Kidney Transplantation , Humans , Delayed Graft Function/etiology , Kidney Transplantation/adverse effects , Retrospective Studies , Kidney , Perfusion , Graft Survival , Risk Factors , Tissue DonorsABSTRACT
BACKGROUND: D40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis has rarely been reported, and its genotype-phenotypic correlation remains elusive. CASE PRESENTATION: We describe a five-month-old boy with CD40LG mutation (c.516T > A, p.Tyr172Ter) X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis as the first manifestation. The patient completely recovered after immunotherapy and allogeneic hematopoietic stem cell transplantation. In addition, four previously reported patients with CD40LG mutation with pulmonary alveolar proteinosis were also analyzed. All of these patients presented with early onset of pulmonary infections and a good response to immunotherapy. The structural model of CD40LG indicated that all mutations caused the X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis to be located within the tumor necrosis factor homology domain. CONCLUSIONS: A case was presented, and the characteristics of four cases of CD40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis were summarized. The variant locations may explain the phenotypic heterogeneity of patients with the CD40LG mutation.
Subject(s)
Hyper-IgM Immunodeficiency Syndrome, Type 1 , Hyper-IgM Immunodeficiency Syndrome , Pulmonary Alveolar Proteinosis , Male , Humans , Infant , Pulmonary Alveolar Proteinosis/diagnosis , Pulmonary Alveolar Proteinosis/genetics , Pulmonary Alveolar Proteinosis/therapy , Mutation , Hyper-IgM Immunodeficiency Syndrome, Type 1/complications , Hyper-IgM Immunodeficiency Syndrome, Type 1/diagnosis , Hyper-IgM Immunodeficiency Syndrome, Type 1/genetics , CD40 Ligand/geneticsABSTRACT
Based on orbital angular momentum (OAM) properties of Laguerre-Gaussian beams LG(p,â), a robust optical encoding model for efficient data transmission applications is designed. This paper presents an optical encoding model based on an intensity profile generated by a coherent superposition of two OAM-carrying Laguerre-Gaussian modes and a machine learning detection method. In the encoding process, the intensity profile for data encoding is generated based on the selection of p and â indices, while the decoding process is performed using a support vector machine (SVM) algorithm. Two different decoding models based on an SVM algorithm are tested to verify the robustness of the optical encoding model, finding a BER =10-9 for 10.2 dB of signal-to-noise ratio in one of the SVM models.
ABSTRACT
We evaluated biomarkers related to kidney fibrosis for the outcome of patients with IgA nephropathy (IgAN). Clinical parameters (estimated glomerular filtration rate, hypertension, proteinuria) and histological findings were assessed in 134 patients with IgAN at the time of diagnosis and followed up prospectively (mean follow-up time, 56.5 months). We measured biomarkers of collagen and laminin turnover in serum and urine collected at the time of kidney biopsy using a novel enzyme-linked immunosorbent assay. Linear discriminant analysis and logistic regression models were used to predict the patient's kidney outcome. Five serum and urine biomarkers of laminin and collagen turnover (sLG1M, sPRO-C3, sPRO-C6, uPRO-C6/Cr, uC3M/Cr) could significantly differentiae IgAN patients with a worse prognosis. Clinical parameters (glomerular filtration rate (GFR), proteinuria) distinguished patients at risk of IgAN progression with a specificity of 87.3% and a sensitivity of 45.2% (area under the curve-AUC 0.751). The addition of the biomarkers significantly increased the prognostic ability with a specificity of 85.1% and a sensitivity of 73.3% (AUC 0.905). We have identified three serum (sLG1M, sPRO-C3, sPRO-C6) and two urinary markers (uPRO-C6/Cr, u-C3M /Cr) that significantly improve the prognostic ability of markers of kidney function to identify an IgAN patient's risk of progressing to ESKD.
Subject(s)
Glomerulonephritis, IGA , Humans , Glomerulonephritis, IGA/diagnosis , Glomerulonephritis, IGA/pathology , Laminin , Czech Republic , Kidney/pathology , Proteinuria/pathology , Glomerular Filtration Rate , Biomarkers , FibrosisABSTRACT
The cells of acute myeloid leukemia are defined by clonal growth and heterogenous immunophenotypes. Chimeric antigen receptors (CARs) commonly recognize molecular targets by single-chain antibody fragments (scFvs) specific to a tumor-associated antigen. However, ScFvs may form aggregates, thus stimulating tonic CAR T-cell activation and reducing CAR T-cell functioning in vivo. Harnessing natural ligands as recognition parts of CARs, specific targeting of membrane receptors can be achieved. Previously, we presented ligand-based Flt3-CAR T-cells targeting the Flt3 receptor. The extracellular part of Flt3-CAR consisted of full-size Flt3Lg. Meanwhile, upon recognition, Flt3-CAR may potentially activate Flt3, triggering proliferative signaling in blast cells. Moreover, the long-lasting presence of Flt3Lg may lead to Flt3 downregulation. In this paper, we present mutated Flt3Lg-based Flt3m-CAR ('m'-for 'mutant') T-cells targeting Flt3. The extracellular part of Flt3m-CAR consists of full-length Flt3Lg-L27P. We have determined that ED50 for recombinant Flt3Lg-L27P produced in CHO cells is at least 10-fold higher than for the wild-type Flt3Lg. We show that the mutation in the recognizing domain of Flt3m-CAR did not affect the specificity of Flt3m-CAR T-cells when compared to Flt3-CAR T-cells. Flt3m-CAR T-cells combine the specificity of ligand-receptor recognition with reduced Flt3Lg-L27P bioactivity, leading to potentially safer immunotherapy.
Subject(s)
Leukemia, Myeloid, Acute , Receptors, Chimeric Antigen , Animals , Cricetinae , Humans , Ligands , Cricetulus , Leukemia, Myeloid, Acute/therapy , Leukemia, Myeloid, Acute/genetics , Signal Transduction , fms-Like Tyrosine Kinase 3/genetics , Receptors, Chimeric Antigen/geneticsABSTRACT
It was recently shown that pyroptosis, an inflammatory form of programmed cell death, is critically involved in the pathogenesis of ischemic stroke. Liraglutide (Lg) is a novel long-acting analog of glucagon-like peptide-1 that has potential protective effects against stroke. However, the relationship between Lg and pyroptosis in the brain is not well defined. In this study, we found that injection of Lg significantly improved the recovery of motor function, increased cerebral blood flow and ameliorated cerebral damage in a mouse model of focal cerebral cortical ischemia. Our results revealed that Lg treatment significantly reduced the levels of NLRP3, Caspase1, IL-1ß and the pore-forming protein gasdermin D in microglial cells in vitro, suggesting that the neuroprotective effect of Lg may be achieved through the inhibition of pyroptosis. Furthermore, by using a specific inhibitor of NOD-like receptor protein 3 (NLRP3), we confirmed that the antipyroptotic mechanism of Lg may be mediated by NLRP3 in vivo. Our present study unveils a novel neuroprotective mechanism through which Lg alleviates ischemia by exerting NLRP3-dependent antipyroptotic effects.
Subject(s)
Brain Ischemia , Stroke , Animals , Brain Ischemia/drug therapy , Brain Ischemia/metabolism , Inflammasomes/metabolism , Liraglutide/pharmacology , Liraglutide/therapeutic use , Mice , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pyroptosis , Stroke/metabolismABSTRACT
An electrochemiluminescence (ECL) aptasensor for the detection of the milk protein allergen ß-lactoglobulin (ß-LG) using nanocomposite as luminophore was fabricated. The Ru-AuNPs/GNP/Naf complex was formed by combining the Rubpy32+-AuNPs complex (Ru-AuNPs), prepared by modifying the negatively charged surface of gold nanoparticles (AuNPs) with positively charged Rubpy32+ through electrostatic interactions and the graphene nanoplatelets-Nafion (GNP/Naf) at a ratio of 2:1. The nanocomposite was coated on the surface of the screen-printed electrode (SPCE) through the film-forming properties of Nafion. A layer of chitosan (CS) was coated onto this modified electrode, and later amine-terminated ß-LG aptamers were covalently attached to the CS/Ru-AuNP/GNP/Naf via glutaraldehyde (GLUT) cross-linking. When ß-LG was incubated with the aptasensor, a subsequent decrease in ECL intensity was recorded. Under the optimal conditions, the ECL intensity of the aptasensor changed linearly with the logarithmic concentration of ß-LG, in the range 0.1 to 1000 pg/ml, and the detection limit was 0.02 pg/mL (3σ/m). The constructed aptasensor displayed simple and fast determination of ß-LG with excellent reproducibility, stability, and high specificity. Additionally, the proposed ECL aptasensor displayed high recoveries (92.5-112%) and low coefficients of variation (1.6-7.8%), when ß-LG fortified samples were analyzed. Integrating Ru-AuNPs/GNP/Naf nanocomposite in the ECL aptasensor paves the way towards a cost-effective and sensitive detection of the milk allergen ß-LG.
Subject(s)
Biosensing Techniques , Metal Nanoparticles , Nanocomposites , Electrochemical Techniques , Gold , Lactoglobulins , Luminescent Measurements , Reproducibility of ResultsABSTRACT
INTRODUCTION: Malignant pleural mesothelioma (MPM) is an aggressive malignant disease with a poor prognosis, which affects the surface mesothelium of the pleural cavity. Immune checkpoints are responsible for controlling the immune system to avoid autoimmunity and prevent tissue damage. In this study, we aimed to investigate the expression of cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed death ligand 1 (PD-L1), and programmed death ligand 2 (PD-L2) immuno-control receptors in MPM patients and the relationship of the expression with tumour types and prognostic parameters. MATERIAL AND METHODS: In this study, we evaluated 50 MPM cases. Immunohistochemically CTLA-4, PD-L1, and PD-L2 were detected by using monoclonal anti-CTLA-4, anti-PD-L1, and anti-PD-L2. Real-time polymerase chain reaction (RT-PCR) analysis was performed with the primers CTLA-4, PD-L1, and PD-L2. RESULTS: Statistically, no significant relation was determined between the PD-L1, PD-L2, and CTLA-4 expressions (immunohistochemical and RT-PCR methods) and the MPM histological type. Interestingly significant correlation was observed between the mean survival time and immunohistochemical PD-L2 expression; thus, long-term survival was observed in cases with PD-L2 expression. CONCLUSIONS: Programmed death ligand 1, PD-L2, and CTLA-4 expression were observed in some MPM cases, suggesting that treatments targeting immune checkpoints may be effective. Because immunohistochemical expression of PD-L2 is associated with better prognosis, it may provide useful clues in the follow-up of patients.
Subject(s)
Lung Neoplasms , Mesothelioma, Malignant , Mesothelioma , Pleural Neoplasms , Humans , B7-H1 Antigen/metabolism , Biomarkers, Tumor/analysis , Immunohistochemistry , Lung Neoplasms/metabolism , Mesothelioma/metabolism , Prognosis , Programmed Cell Death 1 Ligand 2 Protein/genetics , Real-Time Polymerase Chain ReactionABSTRACT
1,3,3-Trinitroazetidine (TNAZ) has good thermal stability and low shock sensitivity, among other properties, and it has broad prospects in insensitive ammunition applications. In this study, a molecular dynamics calculation based on the ReaxFF-lg force field and multiscale shock technique (MSST) was used to simulate the shock-induced chemical reaction of TNAZ with different shock wave directions. The results showed that the shock sensitivity of TNAZ was in the order of [100] > [010] > [001]. There were significant differences in molecular arrangements in different shock directions, which affected the reaction rate and reaction path in different directions. The molecular arrangement in the [010] and [001] directions formed a "buffer" effect. The formation and cleavage of bonds, formation of small molecules and growth of clusters were analyzed to show the effect of the "buffer". The polymerization reactions in the [010] and [001] directions appeared later than that in the [100] direction, and the cluster growth in the [010] and [001] directions was slower than that in the [100] direction. In different shock loading directions, the formation and cleavage mechanisms of the N-O bonds of the TNAZ molecules were different, which resulted in differences in the initial reaction path and reaction rate in the three directions
Subject(s)
Azetidines , Molecular Dynamics Simulation , Anisotropy , Azetidines/chemistry , Nitro Compounds/chemistryABSTRACT
BACKGROUND: NCR3LG1 (B7-H6) protein is selectively overexpressed on tumour and is associated with fatal disease progression of various cancer. However, its prognostic value in bladder cancer (BCa) has not been well elaborated. METHODS: We examined the expression of NCR3LG1 in human BCa and analysed its clinical significance and prognostic value. Meanwhile, the expression of NCR3LG1 was intervened in human BCa cell line 253JBV to analyse subsequent effects on tumour. RESULTS: According to TCGA data, the disease-free survival rate was statistically significant between the NCR3LG1 high expression group and the low expression group (Log Rank p = 0.006). Immunohistochemical staining showed that the expression of NCR3LG1 in BCa tissue was significantly higher than that in adjacent tissues (p < 0.0001), which was positively correlated with TNM staging (p = 0.008), histological grade (p = 0.022), and lymphoma metastasis of BCa (p = 0.032). The proliferation (p < 0.0001), invasion (p < 0.001) and migration ability (p < 0.001) of 253JBV cells are significantly inhibited by knocking down the expression of NCR3LG1, and the cell cycle arrest is induced at the G1 phase, which accelerates the apoptosis of BCa cells (p < 0.005). CONCLUSION: Our findings indicate that NCR3LG1 is involved in the progression of human BCa and may become a potential prognostic biomarker for BCa.
Subject(s)
B7 Antigens/metabolism , Biomarkers, Tumor/metabolism , Urinary Bladder Neoplasms/metabolism , Adult , Aged , Aged, 80 and over , Apoptosis , B7 Antigens/genetics , Biomarkers, Tumor/genetics , Cell Line, Tumor , Cell Movement , Cell Proliferation , Disease-Free Survival , Female , G1 Phase Cell Cycle Checkpoints , Gene Expression Regulation, Neoplastic , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Neoplasm Staging , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/surgery , Young AdultABSTRACT
Sevoflurane has been reported to have anti-tumorigenic effects in glioma. Circ_0000215 was found to play vital functions in the pathological progressions of glioma. However, whether circ_0000215 mediates the inhibitory effects of sevoflurane on glioma cells remains unclear. In vitro assays were performed using cell counting kit-8, flow cytometry, transwell and Western blot assays. The expression levels of circ_0000215, microRNA (miR)-1200 and NCR3LG1 (Natural Killer Cell Cytotoxicity Receptor 3 Ligand 1) were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and/or Western blot. The dual-luciferase reporter assay and pull-down assay were used to investigate the relationship between miR-1200 and circ_0000215 or NCR3LG1. In vivo assay was conducted using xenograft nude mice model. In vitro assays suggested that sevoflurane repressed glioma cell proliferation, metastasis and induced apoptosis as well as hindered tumor growth in vivo, which were reversed by circ_0000215 overexpression. Mechanically, circ_0000215 was confirmed to directly target miR-1200, and NCR3LG1 was a target of miR-1200 in glioma cells. Importantly, circ_0000215 could regulate NCR3LG1 expression via miR-1200. Besides that, rescue assay suggested that circ_0000215 attenuated the inhibitory effects of sevoflurane on glioma cell growth and metastasis, which were reversed by miR-1200 overexpression or NCR3LG1 knockdown. Our study revealed that sevoflurane could suppress glioma tumorigenesis by regulating circ_0000215/miR-1200/NCR3LG1 axis, suggesting a new insight into the therapeutic potential of sevoflurane in glioma treatment.
Subject(s)
Brain Neoplasms , Glioma , MicroRNAs , Animals , B7 Antigens/pharmacology , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Movement , Glioma/drug therapy , Glioma/metabolism , Humans , Mice , Mice, Nude , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , Sevoflurane/pharmacology , Sevoflurane/therapeutic useABSTRACT
The high diversity of sex chromosomes and sex determination systems among haplotilapiines suggests that this large cichlid clade is a good model for investigating the evolution of genetics of sex determination. Nonetheless, information about sex determination in this clade remains sparse. The present study reports a microsatellite marker that is closely associated with sex in Xenotilapia rotundiventralis from Lake Tanganyika, Africa. This study is the first to suggest the role of linkage group 17 in sex determination in haplotilapiine cichlids.
Subject(s)
Cichlids , Animals , Cichlids/genetics , Lakes , Microsatellite Repeats , Phylogeny , TanzaniaABSTRACT
A series of rhodamine B (RhB) encapsulated zeolitic imidazolate framework-8 (RhB@ZIF-8) composite nanomaterials with different concentrations of guest loadings have been synthesized and characterized in order to investigate their applicability to solid-state white-light-emitting diodes (WLEDs). The nanoconfinement of the rhodamine B dye (guest) in the sodalite cages of ZIF-8 (host) is supported by fluorescence spectroscopic and photodynamic lifetime data. The quantum yield (QY) of the luminescent RhB@ZIF-8 material approaches unity when the guest loading is controlled at a low level: 1 RhB guest per ~7250 cages. We show that the hybrid (luminescent guest) LG@MOF material, obtained by mechanically mixing a suitably high-QY RhB@ZIF-8 red emitter with a green-emitting fluorescein@ZIF-8 "phosphor" with a comparably high QY, could yield a stable, intensity tunable, near-white light emission under specific test conditions described. Our results demonstrate a novel LG@MOF composite system exhibiting a good combination of photophysical properties and photostability, for potential applications in WLEDs, photoswitches, bioimaging and fluorescent sensors.
ABSTRACT
We report a reactive molecular dynamic (ReaxFF-MD) study using the newly parameterized ReaxFF-lg reactive force field to explore the initial decomposition mechanism of 3-Nitro-1,2,4-triazol-5-one (NTO) under shock loading (shock velocity >6 km/s). The new ReaxFF-lg parameters were trained from massive quantum mechanics data and experimental values, especially including the bond dissociation curves, valence angle bending curves, dihedral angle torsion curves, and unimolecular decomposition paths of 3-Nitro-1,2,4-triazol-5-one (NTO), 1,3,5-Trinitro-1,3,5-triazine (RDX), and 1,1-Diamino-2,2-dinitroethylene (FOX-7). The simulation results were obtained by analyzing the ReaxFF dynamic trajectories, which predicted the most frequent chain reactions that occurred before NTO decomposition was the unimolecular NTO merged into clusters ((C2H2O3N4)n). Then, the NTO dissociated from (C2H2O3N4)n and started to decompose. In addition, the paths of NO2 elimination and skeleton heterocycle cleavage were considered as the dominant initial decomposition mechanisms of NTO. A small amount of NTO dissociation was triggered by the intermolecular hydrogen transfer, instead of the intramolecular one. For α-NTO, the calculated equation of state was in excellent agreement with the experimental data. Moreover, the discontinuity slope of the shock-particle velocity equation was presented at a shock velocity of 4 km/s. However, the slope of the shock-particle velocity equation for ß-NTO showed no discontinuity in the shock wave velocity range of 3-11 km/s. These studies showed that MD by using a suitable ReaxFF-lg parameter set, could provided detailed atomistic information to explain the shock-induced complex reaction mechanisms of energetic materials. With the ReaxFF-MD coupling MSST method and a cheap computational cost, one could also obtain the deformation behaviors and equation of states for energetic materials under conditions of extreme pressure.
ABSTRACT
The aim of the current study was to investigate the dual effect of an amorphous solid dispersion generated by hot melt extrusion and the addition of pH modifiers on the solubility and stability of telmisartan. Hydroxypropyl methylcellulose acetate succinate L grade was used as a polymeric carrier and recrystallization inhibitor, and meglumine, sodium carbonate, or Neusilin S2 were incorporated as pH modifiers to generate a desirable microenvironmental pH in the solid dispersions. Differential scanning calorimetry, powder X-ray diffraction, and Fourier transform infrared spectroscopy were incorporated to obtain the solid-state characterizations of telmisartan, and the results confirm a partial transformation of telmisartan to an amorphous state. An in vitro release study revealed that the transformation of telmisartan to an amorphous material improved its dissolution rate by 2-fold compared to pure drug and by up to 5-fold with the incorporation of pH modifiers. Results of the stability studies demonstrated that the samples have no significant degradation under accelerated stability conditions at 40 °C/75% RH.