Exogenous nitric oxide stimulates early egress of Eimeria tenella sporozoites from primary chicken kidney cells in vitro

Egress plays a vital role in the life cycle of apicomplexan parasites including Eimeria tenella, which has been attracting attention from various research groups. Many recent studies have focused on early egress induced by immune molecules to develop a new method of apicomplexan parasite elimination. In this study, we investigated whether nitric oxide (NO), an immune molecule produced by different types of cells in response to cytokine stimulation, could induce early egress of eimerian sporozoites in vitro. Eimeria tenella sporozoites were extracted and cultured in primary chicken kidney cells. The number of sporozoites egressed from infected cells was analyzed by flow cytometry after treatment with NO released by sodium nitroferricyanide (II) dihydrate. The results showed that exogenous NO stimulated the rapid egress of E. tenella sporozoites from primary chicken kidney cells before replication of the parasite. We also found that egress was dependent on intra-parasitic calcium ion (Ca2+) levels and no damage occurred to host cells after egress. The virulence of egressed sporozoites was significantly lower than that of fresh sporozoites. The results of this study contribute to a novel field examining the interactions between apicomplexan parasites and their host cells, as well as that of the clearance of intracellular pathogens by the host immune system

Increased Neutralizing Antibody Production and Interferon-γ Secretion in Response to Porcine Reproductive and Respiratory Syndrome Virus Immunization in Genetically Modified Pigs

T cell-mediated immunity plays a prominent role in combating pathogens infection. Both the engagement of the T cell receptor with the peptide-bound major histocompatibility complex and a costimulatory signal are needed for the complete activation of the T cell. To determine whether host immune responses to vaccination could be improved by enhancing CD28-mediated costimulation and verify whether the boosted immune responses could protect the host against viral challenge, we produced a transgenic pig line expressing an extra copy of the CD28 gene controlled by its own promoter at the Rosa26 locus. As expected, in response to porcine reproductive and respiratory syndrome virus (PRRSV) strain vaccination, CD4+ T cells was remarkably increased in CD28 transgenic pigs and a similar response in CD8+ T cells was elicited after challenge. Importantly, because of increased T cell frequencies, the virus-neutralizing antibody against JXA-1 (a highly pathogenic Chinese PRRSV strain), as well as interferon-γ secretion, were enhanced in transgenic pigs. These findings in our translational study provide a novel concept for farm animal breeding in disease resistance, in which we may use the transgenic technology to force overexpression of confirmed immunity-promoting molecules like CD28 and produce an animal with enhanced immune responses to vaccination and broad-spectrum resistance to infectious diseases

Several Critical Cell Types, Tissues, and Pathways Are Implicated in Genome-Wide Association Studies for Systemic Lupus Erythematosus

We aimed to elucidate the cell types, tissues, and pathways influenced by common variants in systemic lupus erythematosus (SLE). We applied a nonparameter enrichment statistical approach, termed SNPsea, in 181 single nucleotide polymorphisms (SNPs) that have been identified to be associated with the risk of SLE through genome-wide association studies (GWAS) in Eastern Asian and Caucasian populations, to manipulate the critical cell types, tissues, and pathways. In the two most significant cells’ findings (B lymphocytes and CD14+ monocytes), we subjected the GWAS association evidence in the Han Chinese population to an enrichment test of expression quantitative trait locus (QTL) sites and DNase I hypersensitivity, respectively. In both Eastern Asian and Caucasian populations, we observed that the expression level of SLE GWAS implicated genes was significantly elevated in xeroderma pigentosum B cells (P ≤ 1.00 × 10−6), CD14+ monocytes (P ≤ 2.74 × 10−4) and CD19+ B cells (P ≤ 2.00 × 10−6), and plasmacytoid dendritic cells (pDCs) (P ≤ 9.00 × 10−6). We revealed that the SLE GWAS-associated variants were more likely to reside in expression QTL in B lymphocytes (q1/q0 = 2.15, P = 1.23 × 10−44) and DNase I hypersensitivity sites (DHSs) in CD14+ monocytes (q1/q0 = 1.41, P = 0.08). We observed the common variants affected the risk of SLE mostly through by regulating multiple immune system processes and immune response signaling. This study sheds light on several immune cells and responses, as well as the regulatory effect of common variants in the pathogenesis of SLE

Immunization against inhibin DNA vaccine as an alternative therapeutic for improving follicle development and reproductive performance in beef cattle

The objective of the present study was to investigate the potential role of immunization against INH on follicular development, serum reproductive hormone (FSH, E2, and P4) concentrations, and reproductive performance in beef cattle. A total of 196 non-lactating female beef cattle (4-5 years old) with identical calving records (3 records) were immunized with 0.5, 1.0, 1.5, or 2.0 mg [(T1, n = 58), (T2, n = 46), (T3, n = 42) and (T4, n = 36), respectively] of the pcISI plasmid. The control (C) group (n = 14) was immunized with 1.0 mL 0.9% saline. At 21d after primary immunization, all beef cattle were boosted with half of the primary immunization dose. On day 10 after primary immunization, the beef cattle immunized with INH DNA vaccine evidently induced anti-INH antibody except for the T1 group. The T3 group had the greatest P/N value peak among all the groups. The anti-INH antibody positive rates in T2, T3 and T4 groups were significantly higher than that in C and T1 groups. RIA results indicated that serum FSH concentration in T2 group increased markedly on day 45 after booster immunization; the E2 amount in T3 group was significantly increased on day 10 after primary immunization, and the levels of E2 also improved in T2 and T3 groups after booster immunization; the P4 concentration in T2 group was significantly improved on day 21 after primary immunization. Ultrasonography results revealed that the follicles with different diameter sizes were increased, meanwhile, the diameter and growth speed of ovulatory follicle were significantly increased. Furthermore, the rates of estrous, ovulation, conception, and twinning rate were also significantly enhanced. These findings clearly illustrated that INH DNA vaccine was capable of promoting the follicle development, thereby improving the behavioral of estrous and ovulation, eventually leading to an augment in the conception rates and twinning rate of beef cattle

Multiscale materials design of hard coatings for improved fracture resistance and thermal stability

Physical vapor deposited hard coatings comprised of cubic (c) transition metal (TM)-Al-N, and (TM)-Si-N are the current work horse materials for a large number of metal cutting and wear resistant applicatíons to light against the extreme conditions of temperature and stress simultaneously. In spite of a high degree of sophisticatíon in terms of material choice and microstructural design, a lower fracture resistance and limited thermal stability of the coatings remains a technological challenge in the field. The lower fracture resistance ofthe coating is an inherent material property. Limited thermal stability in the TM-Al-N system is associated with the transformation of metastable c -AIN to its stable wurtzite (w)-AIN phase ata temperature above 900 oC resulting an undesirable hardness drop. The current work shows how to overcome these challenges by manipulaling the coating material at different length scales, i.e. microstructure, crystal and interface structure, and alloy design. The endeavor of multiscale materials design is achieved by converging a deeper material and process knowledge to result specific structural modification over multiple length scales by alloying transition metal nitrides with AIN and SiNxs following. Microstructure variation is achieved in ZrN coating by alloying it with SiNx, where the surface segregated SiNx breaks down the columnar structure and evolves a self-organized nanocomposite structure with a hardness variation from 37 ±2 GPa to 26 ±1 GPa. The indentation induced fracture studies reveal crack deflection for the colum nar coating, likely a long the coiumn boundaries. The crack deflection olfers additional energy dissipative mechanisms that make the columnar structured coating more fracture resistant, which is not the case fur the nanocomposite coating in spite of its lower hardness. Crystal structure of AIN is variad between stable wurtzite structure to metastable cubic structure in the ZrAIN alloy by adapting a mullilayer structure and tuning the layerthickness. The multilayer consisting c-AIN layer shows a hardness of 34 ±1 GPa anda twofold enhancement in the critica! force to cause an indentation induced surface crack compared to the multilayer containing w-AIN in spite of a lower hardness for the later case. The higher fracture resistance is discovered to be ca u sed by stress- induced transformation of /IJN from its metastable cubic structure to its thermodynamically stable wurtzite structure associated with a molar volume expansion of20% that builds up local compressive stress zones delay;ng the onset and propagation of the cracks. This is in fact the first experím en tal data point for the stress-induced transfurmation toughening in a hard coatíng. The current work also demonstrates a concept of im proving the thermal stabilíty ofTM-Al-N by m odifying the interface structure between w-AIN and c-TMN. A popular belief in the field is that AIN in lis stable wurtzite structure is detrimental to coating hardness, and hence the curren! material design strategy Is to force AIN in metas table cubic phase that confines the application temperature (- 900 oC). In contrast, here it is shown that the w-AIN offers a high hardness provided if it is grown (semi-)coherent to c-TMN. This is experimentally shown for lhe multilayer system ofTiN/ZrAIN. The interface structure between the c-TiN, c-ZrN and w-AIN is transformed from incoherent to (semi-)coherent structure bytuning the growth conditions under a favorable crystallographic template. Furthennore, the low energy(semi-) coherent interface structure between w-AIN and c- TiN, c- ZrN display a high thermal stability, causing a high and more stable hardness up to an annealing temperature of 1150 oC with a value of34± 1.5 GPa. This value is 50 % higher comparad to the state-of-the-art monolithic and multilayered Ti-/IJ -N and Zr-Al-N coating containing incoherent w-AIN. Finally, an entropy based alloy design concept is explorad to form a thermodynamicLos recubrimientos duros formados por metales de transición (TM) cúbicos -AlN, y -SiN depositados mediante fase de vapor (CVD) son materiales extensamente utilizados en gran número de aplicaciones de corte y de desgaste bajo condiciones extremas de temperatura y solicitaciones mecánicas. A pesar de un alto grado de sofisticación en cuanto a la selección del material y el diseño microestructural, la baja resistencia a la fractura y la limitada estabilidad térmica sigue siendo un importante reto tecnológico. La variación microestructural en los recubrimientos de ZrN se controla mediante la aleación con SiNx, ya que la segregación superficial de SiNx rompe la estructura columnar y evoluciona a un nanocompuesto autoorganizado con una dureza de entre 37 ±2 GPa y 26 ±1 GPa. Las grietas producidas por indentación muestran la existencia de deflexión de grieta, lo que proporciona un mecanismo de disipación de energía adicional, haciendo de este material más resistente a la generación de grieta.La estructura cristalina del recubrimiento de AlN se varía entre la fase estable wurtzita y la fase cúbica estable ZrAlN mediante el control de la estructura y el espesor de la arquitectura multicapa. El recubrimiento multicapa formado por la fase c-AlN presenta una dureza de 34 ±1 GPa y una resistencia a la generación de grietas por indentación dos veces mayor comparado con el recubrimiento multicapa formado por w-AlN, aunque éste presente una dureza menor. La mayor resistencia a fractura está causada por la transformación inducida por tensión de AlN desde la fase cúbica metaestable a la fase wurtzita termodinámicamente estable acompañada de una expansión molar del 20%, resultando en una generación de tensiones compresivas que retarda la generación y propagación de grietas. Esta es la primera vez que se reporta la existencia de transformación catalizada por tensión en recubrimientos duros. En esta tesis también se demuestra el concepto de mejorar la estabilidad térmica de los recubrimientos basados en TM-Al-N mediante la modificación de la estructura interfacial entre las fases w-AlN y c-TMN. En general la existencia de AlN en su fase estable wurtzita puede ser detrimental para la dureza, y por lo tanto se suele depositar el material en la fase cúbica, lo que limita la temperatura de utilización (~ 900 oC). Esta dureza es un 50%mayor de la dureza reportada para recubrimientos monolíticos y multicapas de Ti-Al-N y Zr-Al-N que contengan fase incoherente de w-AlN. Finalmente, el concepto de aleaciones de alta entropía se utiliza para depositar una solución sólida termodinámicamente estable del sistema TM-Al-N que presenta una entalpía de mezcla positiva. Elementos de aleación multi-principales de (AlTiVCrNb)N se utilizan para formar una solución sólida cúbica . La alta entropía configuracional en la mezcla es mayor que la entalpía, por lo que se espera una formación de solución sólida estabilizada a temperaturas mayores de 1000K. Sin embargo, a temperaturas elevadas, la optimización entre la minimización de la energía de interacción y la maximización del desorden configuracional causa la precipitación de AlN en su estructura wurtzita estable, y la solución sólida cúbica está únicamente confinada entre TiN, CrN , VN y NbN que tienen baja entalpía de mezcla. En resumen, esta tesis presenta soluciones tecnológica a dos retos importantes en el campo. Se consigue una mejora significativa en la resistencia a fractura en los recubrimientos mediante la selección de materiales y el diseño microestructural mediante mecanismos de deflexión de grieta y transformación de fase asistida por tensión. Así mismo, se aumenta la estabilidad térmica de recubrimientos TM-Al-N mediante una nueva microestructura consistente en c-TMN y w-AlN termodinámicamente estable con una estructura interfacial (semi-)coherente de baja energía