Oral Bacterial Infection and Shedding in <i>Drosophila Melanogaster</i>

International audienceThe fruit fly Drosophila melanogaster is one of the best developed model systems of infection and innate immunity. While most work has focused on systemic infections, there has been a recent increase of interest in the mechanisms of gut immunocompetence to pathogens, which require methods to orally infect flies. Here we present a protocol to orally expose individual flies to an opportunistic bacterial pathogen (Pseudomonas aeruginosa) and a natural bacterial pathogen of D. melanogaster (Pseudomonas entomophila). The goal of this protocol is to provide a robust method to expose male and female flies to these pathogens. We provide representative results showing survival phenotypes, microbe loads, and bacterial shedding, which is relevant for the study of heterogeneity in pathogen transmission. Finally, we confirm that Dcy mutants (lacking the protective peritrophic matrix in the gut epithelium) and Relish mutants (lacking a functional immune deficiency (IMD) pathway), show increased susceptibility to bacterial oral infection. This protocol, therefore, describes a robust method to infect flies using the oral route of infection, which can be extended to the study of a variety genetic and environmental sources of variation in gut infection outcomes and bacterial transmission

Elevated expression of L-selectin ligand in lymph node-derived human prostate cancer cells correlates with increased tumorigenicity.

Human prostate cancer LNCaP cells including C-33 and C-81 cells were originally derived from the lymph nodes of a patient with metastatic prostate cancer. These two cells were employed for characterization of L-selectin ligand and in vitro tumorigenicity, because they mimic the clinical conditions of early and late-stage human prostate cancer. C-81 cells exhibit higher in vitro migratory and invasive properties as compared with C-33 cells. We find that the L-selectin ligand and mucin glycan-associated MECA-79 epitope were elevated in C-81 cells. An increase of these glycotopes positively correlates with elevated tumorigenicity and expression of key glycosyl- and sulfotransferase genes. These results suggest that modulated expression of selective glycogenes correlates with altered tumorigenicity of cancer cells

Dynamics of High-speed Machining of Aerospace Structures using Finite-element Analysis

"The study is aimed to investigate certain aspects of high-speed machining for improving the accuracy of thin-walled aerospace components. The approach used involved the development of finite-element model of the workpiece to be machined and its subsequent frequency response analysis. The response of the workpiece subjected to dynamic cutting force gives an indication of the best possible speeds from the point of view of accuracy. Based on the results of the analysis, it is possible to predict the range of spindle speeds at which the workpiece demonstrates very high dynamic rigidity. In addition, this study has established the superiority of high-speed machining to produce aerospace structures with high stiffness-to-weight ratio and also throws some light on the capability of high speed in machining of low rigidity sculptured-surface components.

Interplay of Macroeconomics and CO2 Emissions Dynamics: Evidence from Top CO2 Emitting Economies

Understanding the dynamic connection between macroeconomic factors and CO2 emissions is vital for developing sustainable and environmentally conscious economic systems. Utilizing a 30-year dataset from the World Bank, focusing on the top 10 CO2-emitting nations, the study employs the Vector Error Correction Model (VECM) to capture both long-term and short-term causal relationships. Descriptive statistics showcase per capita CO2 emissions averaging 8.77 metric tons with notable variability. Key economic indicators, including forest area, foreign direct investment, trade, and GDP, exhibit dynamic trends. Renewable energy consumption averages 15.02%, while energy use per capita stands at 3579.16 kg of oil equivalent. Agricultural land constitutes 32.48%, and the estimated rural population percentage is approximately 33.94%. The VAR model with nine equations is thoroughly evaluated using criteria like BIC (125.280) and HQIC (122.177), signifying model fitting. Coefficients in the model highlight the impact of lagged values on the dependent variable, such as the statistically significant lagged CO2 emissions variable at lag 1. The Impulse Response Function (IRF) illustrates dynamic responses to variable shocks. Forecast Error Variance Decomposition (FEVD) emphasizes the heavy reliance on past values for short-term CO2 forecasts, with external factors gaining significance over longer horizons. This comprehensive approach enhances the understanding of variable contributions to forecast uncertainty, emphasizing the importance of integrating economic development with environmental stewardship

Effect of MUC16 Blockade using the Humanized AR9.6 Antibody in Patient Derived Organoid Models of PDAC

Pancreatic Ductal Adenocarcinoma (PDAC) represents nearly 90% of all pancreatic cancer cases. 49,830 of the 62,210 patients diagnosed in 2022 are estimated to succumb to the malignancy. Early diagnosis of the disease is uncommon as most patients present with symptoms when the cancer is late-stage and metastatic. This decreases the likelihood of successful surgical resection and increases the dependency on standard of care chemotherapy leads to which is met with therapeutic resistance, demonstrated by the 5-year post-diagnosis survival rate of a mere 11.5%. Mucin-16, a heavy glycosylated transmembrane protein is overexpressed in more than 65% PDAC cases. AR9.6 is an anti-MUC16 antibody that has been recently humanized after evidence of its therapeutic potential was found in an orthotopic study utilizing the murine version of the antibody. The HuAR9.6 antibody efficiently binds MUC16 expressed on tumor cells, and can both inhibit downstream oncogenic signaling and elicit tumor killing by signaling the immune system to the tumor. In this project, we used RNA sequencing to evaluate the MUC16 mediated transcriptomic changes by using the humanized AR9.6 antibody in patient-derived organoid models of PDAC. To begin this study, organoids were developed using tumor cells from a primary PDAC tumor with a high MUC16 profile obtained from rapid autopsy patient #142 from the Rapid Autopsy Program at UNMC. The organoids were then treated in triplicates using a monoclonal antibody HuIgG as an isotype control due to its lack of specificity, and the test arm of study, HuAR9.6. These samples were treated with 40 ug/mL of the antibodies for a 24-hour period, post which RNA isolation was performed. RNA sequencing and subsequent Gene Ontology and KEGG enrichment analysis revealed a downregulation of genes involved in the Hippo signaling pathway, fat digestion and absorption and TGF-β signaling. Based on this gene expression profiling, we hypothesize that HuAR9.6 can slow tumor progression by downregulating the Hippo and TGF-β signaling pathways. In the future, we aim to robustly validate these results at the level of the proteome and assess if these results can be reproduced in multiple patient samples with the hope to translate this antibody to the clinic to be used in PDAC patients who have a high MUC16 expression.https://digitalcommons.unmc.edu/surp2022/1038/thumbnail.jp

TNFα enhances the motility and invasiveness of prostatic cancer cells by stimulating the expression of selective glycosyl- and sulfotransferase genes involved in the synthesis of selectin ligands.

Sialyl Lewis x (sLe(x)) plays an important role in cancer metastasis. But, the mechanism for its production in metastatic cancers remains unclear. The objective of current study was to examine the effects of a proinflammatory cytokine on the expression of glycosyltransferase and sulfotransferase genes involved in the synthesis of selectin ligands in a prostate cancer cell line. Androgen-independent human lymph node-derived metastatic prostate cancer cells (C-81 LNCaP), which express functional androgen receptor and mimic the castration-resistant advanced prostate cancer, were used. TNFα treatment of these cells increased their binding to P-, E- and L-selectins, anti-sLe(x) antibody, and anti-6-sulfo-sialyl Lewis x antibody by 12%, 240%, 43%, 248% and 21%, respectively. Also, the expression of C2GnT-1, B4GalT1, GlcNAc6ST3, and ST3Gal3 genes was significantly upregulated. Further treatment of TNFα-treated cells with either anti-sLe(x) antibody or E-selectin significantly suppressed their in vitro migration (81% and 52%, respectively) and invasion (45% and 56%, respectively). Our data indicate that TNFα treatment enhances the motility and invasion properties of LNCaP C-81 cells by increasing the formation of selectin ligands through stimulation of the expression of selective glycosyl- and sulfotransferase genes. These results support the hypothesis that inflammation contributes to cancer metastasis

Climatic Determinants of Shrimp Yields in Tamil Nadu, India: A Transfer Function Analysis

Shrimp aquaculture in Tamil Nadu plays a critical role in supporting livelihoods and contributing to exports but is increasingly vulnerable to climatic variability. This study investigates how seasonal precipitation, extreme temperatures, and lagged production impact shrimp yields in four key districts—Tiruvallur, Cuddalore, Thanjavur, and Nagapattinam—over the period 2015–2023. Using statistical models, we identify major trends and district-specific sensitivities. For instance, excessive summer and winter precipitation coupled with high maximum temperatures reduced yields in Tiruvallur, whereas warmer summer nights boosted production. In Cuddalore, yields were hampered by seasonal precipitation, elevated minimum temperatures, and the lingering effects of previous yields. Thanjavur’s production suffered from extreme temperatures and winter rainfall but benefited from milder winter nights. Nagapattinam showed unique dynamics, where winter precipitation and summer maximum temperatures enhanced yields, while summer rainfall and lagged production had adverse effects. These findings highlight the need for tailored, district-specific strategies to manage climate risks and sustain shrimp farming. For example, adaptive measures such as optimizing water management or selecting climate-resilient shrimp varieties could mitigate negative impacts. Future research could integrate factors like water quality and disease outbreaks to strengthen the sector’s resilience further

Effect of heat source on the growth of dendritic drying patterns

Shining a tightly-focused but low-powered laser beam on an absorber dispersed in a biological fluid gives rise to spectacular growth of dendritic patterns. These result from localized drying of the fluid because of efficient absorption and conduction of optical energy by the absorber. We have carried out experiments in several biologically relevant fluids and have analyzed patterns generated by different types of absorbers. We observe that the growth velocity of branches in the dendritic patterns can decrease below the value expected for natural drying

MicroRNA-200c modulates the expression of MUC4 and MUC16 by directly targeting their coding sequences in human pancreatic cancer.

Transmembrane mucins, MUC4 and MUC16 are associated with tumor progression and metastatic potential in human pancreatic adenocarcinoma. We discovered that miR-200c interacts with specific sequences within the coding sequence of MUC4 and MUC16 mRNAs, and evaluated the regulatory nature of this association. Pancreatic cancer cell lines S2.028 and T3M-4 transfected with miR-200c showed a 4.18 and 8.50 fold down regulation of MUC4 mRNA, and 4.68 and 4.82 fold down regulation of MUC16 mRNA compared to mock-transfected cells, respectively. A significant reduction of glycoprotein expression was also observed. These results indicate that miR-200c overexpression regulates MUC4 and MUC16 mucins in pancreatic cancer cells by directly targeting the mRNA coding sequence of each, resulting in reduced levels of MUC4 and MUC16 mRNA and protein. These data suggest that, in addition to regulating proteins that modulate EMT, miR-200c influences expression of cell surface mucins in pancreatic cancer

MUC1 Regulates Expression of Multiple microRNAs Involved in Pancreatic Tumor Progression, Including the miR-200c/141 Cluster

MUC1 is a transmembrane glycoprotein that modulates transcription via its cytoplasmic domain. We evaluated the capacity of MUC1 to regulate the global transcription of microRNAs in pancreatic cancer cells expressing MUC1. Results indicated that MUC1 regulated expression of at least 103 microRNAs. We evaluated further regulation of the microRNA transcript cluster miR-200c/141, which was among the most highly regulated microRNAs. We found that MUC1 directly interacted with ZEB1, a known transcriptional repressor of the miR-200c/141 cluster, at the promoter of miR-200c/141, and further reduced transcript production. These data indicate that signaling through MUC1 influences cancer progression by regulating transcription of microRNAs that are associated with the process of metastasis