25 research outputs found

    A Subset of CXCR5+CD8+ T Cells in the Germinal Centers From Human Tonsils and Lymph Nodes Help B Cells Produce Immunoglobulins

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    Recent studies indicated that CXCR5+CD8+ T cells in lymph nodes could eradicate virus-infected target cells. However, in the current study we found that a subset of CXCR5+CD8+ T cells in the germinal centers from human tonsils or lymph nodes are predominately memory cells that express CD45RO and CD27. The involvement of CXCR5+CD8+ T cells in humoral immune responses is suggested by their localization in B cell follicles and by the concomitant expression of costimulatory molecules, including CD40L and ICOS after activation. In addition, CXCR5+CD8+ memory T cells produced significantly higher levels of IL-21, IFN-γ, and IL-4 at mRNA and protein levels compared to CXCR5−CD8+ memory T cells, but IL-21-expressing CXCR5+CD8+ T cells did not express Granzyme B and perforin. When cocultured with sorted B cells, sorted CXCR5+CD8+ T cells promoted the production of antibodies compared to sorted CXCR5−CD8+ T cells. However, fixed CD8+ T cells failed to help B cells and the neutralyzing antibodies against IL-21 or CD40L inhibited the promoting effects of sorted CXCR5+CD8+ T cells on B cells for the production of antibodies. Finally, we found that in the germinal centers of lymph nodes from HIV-infected patients contained more CXCR5+CD8+ T cells compared to normal lymph nodes. Due to their versatile functional capacities, CXCR5+CD8+ T cells are promising candidate cells for immune therapies, particularly when CD4+ T cell help are limited

    Lingnan University farming fun 2015 = ć¶ș捗èŸČ耕暂2015

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    This video was produced by 5 students of Lingnan University: So Ka Yee, Lu Xiao Ting, Chen Guanying, Leung Tsz Wing, Leung Sze Yuet

    Division of Cow Production Groups Based on SOLOv2 and Improved CNN-LSTM

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    Udder conformation traits interact with cow milk yield, and it is essential to study the udder characteristics at different levels of production to predict milk yield for managing cows on farms. This study aims to develop an effective method based on instance segmentation and an improved neural network to divide cow production groups according to udders of high- and low-yielding cows. Firstly, the SOLOv2 (Segmenting Objects by LOcations) method was utilized to finely segment the cow udders. Secondly, feature extraction and data processing were conducted to define several cow udder features. Finally, the improved CNN-LSTM (Convolution Neural Network-Long Short-Term Memory) neural network was adopted to classify high- and low-yielding udders. The research compared the improved CNN-LSTM model and the other five classifiers, and the results show that CNN-LSTM achieved an overall accuracy of 96.44%. The proposed method indicates that the SOLOv2 and CNN-LSTM methods combined with analysis of udder traits have the potential for assigning cows to different production groups.Applied Science, Faculty ofAlumniNon UBCEngineering, School of (Okanagan)ReviewedFacultyResearcherOthe

    CRISPR/Cas Genome Editing Technologies for Plant Improvement against Biotic and Abiotic Stresses: Advances, Limitations, and Future Perspectives

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    Crossbreeding, mutation breeding, and traditional transgenic breeding take much time to improve desirable characters/traits. CRISPR/Cas-mediated genome editing (GE) is a game-changing tool that can create variation in desired traits, such as biotic and abiotic resistance, increase quality and yield in less time with easy applications, high efficiency, and low cost in producing the targeted edits for rapid improvement of crop plants. Plant pathogens and the severe environment cause considerable crop losses worldwide. GE approaches have emerged and opened new doors for breeding multiple-resistance crop varieties. Here, we have summarized recent advances in CRISPR/Cas-mediated GE for resistance against biotic and abiotic stresses in a crop molecular breeding program that includes the modification and improvement of genes response to biotic stresses induced by fungus, virus, and bacterial pathogens. We also discussed in depth the application of CRISPR/Cas for abiotic stresses (herbicide, drought, heat, and cold) in plants. In addition, we discussed the limitations and future challenges faced by breeders using GE tools for crop improvement and suggested directions for future improvements in GE for agricultural applications, providing novel ideas to create super cultivars with broad resistance to biotic and abiotic stress

    Clinical Characteristics and Outcomes of AIDS-Related Burkitt Lymphoma in China: A Retrospective Single-Center Study

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    Objectives: Studies on the prognosis and risk stratification of patients with acquired immune deficiency syndrome (AIDS) – related Burkitt lymphoma (AR-BL) are rare. We aim to construct a novel model to improve the risk assessment of these patients. Methods: We retrospectively analyzed the clinical data of 34 patients over the past 10 years and the factors associated with progression-free survival (PFS) and overall survival (OS) were evaluated in univariate and multivariate Cox models. Then, the novel model consisting of screened factors was compared with the existing models. Results: With a 37-month median follow-up, the overall 2-year PFS and OS rates were 40.50% and 36.18%, respectively. The OS of patients who received chemotherapy was better compared with those without chemotherapy ( P =  .0012). Treatment with an etoposide, prednisone, oncovin, cyclophosphamide, and hydroxydaunorubicin-based regimen was associated with longer OS and PFS compared with a cyclophosphamide, doxorubicin, vincristine, and prednisone-based regimen (OS, P =  .0002; PFS, P =  .0158). Chemotherapy (hazard ratio [ HR ] = 0.075; 95% confidence interval [CI], 0.009-0.614) and Eastern Cooperative Oncology Group Performance Status (ECOG PS) 2 to 4 ( HR =  4.738; 95% CI, 1.178-19.061) were independent prognostic factors of OS in multivariate analysis and we established a novel prognostic risk stratification model named GZ8H model with chemotherapy and ECOG PS. Conclusion: GZ8H showed better stratification ability than the international prognostic index (IPI) or Burkitt lymphoma IPI (BL-IPI). Furthermore, the C-index of the nomogram used to predict OS was 0.884 in the entire cohort and the calibration curve showed excellent agreement between the predicted and actual results of OS. No human immunodeficiency virus-related factors were found to be associated with OS and PFS of AR-BL patients in our study. Overall, the clinical characteristics and outcomes in AR-BL were shown and prognostic factors for OS and PFS were identified in this study

    Construction of Host Plant Insect‐Resistance Mutant Library by High‐Throughput CRISPR/Cas9 System and Identification of A Broad‐Spectrum Insect Resistance Gene

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    Abstract Insects pose significant challenges in cotton‐producing regions. Here, they describe a high‐throughput CRISPR/Cas9‐mediated large‐scale mutagenesis library targeting endogenous insect‐resistance‐related genes in cotton. This library targeted 502 previously identified genes using 968 sgRNAs, generated ≈2000 T0 plants and achieved 97.29% genome editing with efficient heredity, reaching upto 84.78%. Several potential resistance‐related mutants (10% of 200 lines) their identified that may contribute to cotton‐insect molecular interaction. Among these, they selected 139 and 144 lines showing decreased resistance to pest infestation and targeting major latex‐like protein 423 (GhMLP423) for in‐depth study. Overexpression of GhMLP423 enhanced insect resistance by activating the plant systemic acquired resistance (SAR) of salicylic acid (SA) and pathogenesis‐related (PR) genes. This activation is induced by an elevation of cytosolic calcium [Ca2+]cyt flux eliciting reactive oxygen species (ROS), which their demoted in GhMLP423 knockout (CR) plants. Protein‐protein interaction assays revealed that GhMLP423 interacted with a human epidermal growth factor receptor substrate15 (EPS15) protein at the cell membrane. Together, they regulated the systemically propagating waves of Ca2+ and ROS, which in turn induced SAR. Collectively, this large‐scale mutagenesis library provides an efficient strategy for functional genomics research of polyploid plant species and serves as a solid platform for genetic engineering of insect resistance

    Construction of Host Plant Insect‐Resistance Mutant Library by High‐Throughput CRISPR/Cas9 System and Identification of A Broad‐Spectrum Insect Resistance Gene

    No full text
    Insects pose significant challenges in cotton‐producing regions. Here, they describe a high‐throughput CRISPR/Cas9‐mediated large‐scale mutagenesis library targeting endogenous insect‐resistance‐related genes in cotton. This library targeted 502 previously identified genes using 968 sgRNAs, generated ≈2000 T0 plants and achieved 97.29% genome editing with efficient heredity, reaching upto 84.78%. Several potential resistance‐related mutants (10% of 200 lines) their identified that may contribute to cotton‐insect molecular interaction. Among these, they selected 139 and 144 lines showing decreased resistance to pest infestation and targeting major latex‐like protein 423 (GhMLP423) for in‐depth study. Overexpression of GhMLP423 enhanced insect resistance by activating the plant systemic acquired resistance (SAR) of salicylic acid (SA) and pathogenesis‐related (PR) genes. This activation is induced by an elevation of cytosolic calcium [Ca2+]cyt flux eliciting reactive oxygen species (ROS), which their demoted in GhMLP423 knockout (CR) plants. Protein‐protein interaction assays revealed that GhMLP423 interacted with a human epidermal growth factor receptor substrate15 (EPS15) protein at the cell membrane. Together, they regulated the systemically propagating waves of Ca2+ and ROS, which in turn induced SAR. Collectively, this large‐scale mutagenesis library provides an efficient strategy for functional genomics research of polyploid plant species and serves as a solid platform for genetic engineering of insect resistance
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