Development and validation of a luminescence-based, medium-throughput assay for drug screening in Schistosoma mansoni

Schistosomiasis, one of the world's greatest neglected tropical diseases, is responsible for over 280,000 human deaths per annum. Praziquantel, developed in the 1970s, has high efficacy, excellent tolerability, few and transient side effects, simple administration procedures and competitive cost and it is currently the only recommended drug for treatment of human schistosomiasis. The use of a single drug to treat a population of over 200 million infected people appears particularly alarming when considering the threat of drug resistance. Quantitative, objective and validated methods for the screening of compound collections are needed for the discovery of novel anti-schistosomal drugs. METHODOLOGY/PRINCIPAL FINDINGS: The present work describes the development and validation of a luminescence-based, medium-throughput assay for the detection of schistosomula viability through quantitation of ATP, a good indicator of metabolically active cells in culture. This validated method is demonstrated to be fast, highly reliable, sensitive and automation-friendly. The optimized assay was used for the screening of a small compound library on S. mansoni schistosomula, showing that the proposed method is suitable for a medium-throughput semi-automated screening. Interestingly, the pilot screening identified hits previously reported to have some anti-parasitic activity, further supporting the validity of this assay for anthelminthic drug discovery. CONCLUSIONS: The developed and validated schistosomula viability luminescence-based assay was shown to be successful and suitable for the identification of novel compounds potentially exploitable in future schistosomiasis therapies

Mechanisms of immunosuppression by organotins : apoptosis vs. proliferative arrest

Mechanisms of immunosuppression by organotins-apoptosis vs. proliferative arrest. The organotin compounds di-n-butyltin dichloride (DBTC) and trin-butyltin chloride (TBTC), used as stabilizers and biocides respectively, induce thymus atrophy inhibiting immature thymocyte proliferation. The aim of the study was to examine whether apoptosis has a role in this atrophy and whether DBTC, like TBTC, induces apoptosis in vitro. Thymi from rats treated with a dose (15 mg/kg) of organotin known to reduce thymocyte proliferation, did not show DNA fragmentation. This indicates that apoptosis is not evident in organotin-induced thymus atrophy at low doses. In vitro data showed that 3-5 µM of DBTC or TBTC significantly increased the percentage of apoptotic nuclei in rat thymocytes. Further mechanistic studies indicated a relation between the cytotoxic effects of the compounds and their capacity to induce apoptosis. At lower concentrations than required to induce apoptosis, both organotins inhibited protein and DNA synthesis and increased RNA and heat shock proteins synthesis. We demenstrated that the increase of RNA synthesis occurred in small thymocytes, which comprised the same subset of cells sensitive to apoptosis by organotins. Co-exposure to RNA or protein synthesis inhibitors protected cells from apoptosis by DBTC or TBTC, indicating that macromolecular synthesis is required for the initiation of the prcess. Moreover, two genes (glutathione S-transferase and nur77) were found to be activated under influence of apoptotic concentrations of DBTC. Besides effects on macromolecular synthesis, organotins disrupt energy metabolism and affect mitochondria. Previously, TBTC has been shown to increase intracellular calcium level, to produce reactive oxygen species (ROS) and to release pro-apoptotic factors. We showed similar changes in case of DBTC, i.e. increase of calcium, ROS production, release of cytochrome c and activation of caspase 3. Thus, induction of apoptosis is a relevant mechanism at relatively high concentrations/doses of organotin compounds, while lower concentrations/doses cause a proliferative arrest without signs of apoptosis. Finally, it has been investigated whether DBTC, in vivo was thymus-selective or had a direct effect on peripheral T cell responsiveness as well. We found that DBTC can rapidly and directly inhibit a hapten-specific immune respons, reducing the number of peripheral cells isolated from lymph nodes of sensitized rats. This finding may not have important implications for studying the mechanisms of organotin-induced immunosuppressio

Design and Computational Thinking with IoTgo: What Teachers Think

Computational and design thinking are orthogonal and complementary ways of thinking, which are fundamental for nowadays’ learners and yet taught in isolation. Teachers’ understanding of them can be a barrier to their introduction. This paper reports on an intervention for primary- and secondary-school teachers, introducing them to both forms of thinking through hands-on laboratories, revolving around the IoTgo game-based toolkit. Teachers’ ideas of computational and design thinking were investigated with a questionnaire before and after the intervention. Their answers suggest that the intervention was effective and indicate future work related to computational and design thinking

Implications of metabolism-driven myeloid dysfunctions in cancer therapy

Immune homeostasis is maintained by an adequate balance of myeloid and lymphoid responses. In chronic inflammatory states, including cancer, this balance is lost due to dramatic expansion of myeloid progenitors that fail to mature to functional inflammatory neutrophils, macrophages, and dendritic cells (DCs), thus giving rise to a decline in the antitumor effector lymphoid response. Cancer-related inflammation orchestrates the production of hematopoietic growth factors and cytokines that perpetuate recruitment and activation of myeloid precursors, resulting in unresolved and chronic inflammation. This pathologic inflammation creates profound alterations in the intrinsic cellular metabolism of the myeloid progenitor pool, which is amplified by competition for essential nutrients and by hypoxia-induced metabolic rewiring at the tumor site. Therefore, persistent myelopoiesis and metabolic dysfunctions contribute to the development of cancer, as well as to the severity of a broad range of diseases, including metabolic syndrome and autoimmune and infectious diseases. The aims of this review are to (1) define the metabolic networks implicated in aberrant myelopoiesis observed in cancer patients, (2) discuss the mechanisms underlying these clinical manifestations and the impact of metabolic perturbations on clinical outcomes, and (3) explore new biomarkers and therapeutic strategies to restore immunometabolism and differentiation of myeloid cells towards an effector phenotype to increase host antitumor immunity. We propose that the profound metabolic alterations and associated transcriptional changes triggered by chronic and overactivated immune responses in myeloid cells represent critical factors influencing the balance between therapeutic efficacy and immune-related adverse effects (irAEs) for current therapeutic strategies, including immune checkpoint inhibitor (ICI) therapy

The evolution of a toolkit for smart-thing design with children through action research

Several workshops use toolkits to engage children in the design of smart things, that is, everyday things like toys enhanced with computing devices and capabilities. In general, the toolkits focus on one design stage or another, e.g., ideation or programming. Few toolkits are created to guide children through an entire design process. This paper presents a toolkit for smart-thing design with children. It revolves around SNaP, a card-based board game for children. The toolkit serves to frame the entire design process and guide them through their exploration, ideation, programming and prototyping of their own smart things. By embracing action research, the toolkit was adopted in actions with children, namely, design workshops. Results of actions were reflected over by considering children’s benefits, and they were used to make the toolkit evolve across cycles of action, reflection and development. The paper reports on the latest evolution cycles, ending with the 2020 cycle for continuing smart-thing design during COVID-19 times. The paper concludes with general reflections concerning action research and design with children, toolkits for framing smart-thing design with children, on-going and future work

the science behind vitamins and natural compounds for breast cancer prevention getting the most prevention out of it

Summary This review highlights the role of vitamins and natural compounds in breast cancer prevention, with a particular focus on Vitamin D. In the last decades, both encouraging and discouraging results about the association between antioxidant supplementation and cancer have been reported to public and scientific community. Their safe and favorable toxicity profile makes them suitable to be investigated in a preventive setting. However, a recent large meta-analysis showed that treatment with beta carotene, vitamin A, and vitamin E may increase mortality, whereas the potential roles of vitamin C and selenium on mortality need further study. Likewise, folate levels were not associated with reduced breast cancer risk in a recent meta-analysis. Several studies have shown that a high proportion of women at-risk for breast cancer or affected by the disease have deficient vitamin D levels, i.e., 250H-

News from the San Antonio Breast Cancer Symposium 2022

The 45th San Antonio Breast Cancer Symposium, held December 6–10 in San Antonio, Texas is the largest breast cancer conference and this year saw the participation of nearly 10,000 clinicians, researchers, and patient advocates, in person. Scientists shared many important new findings that are going to change the clinical practice in the near future. Here, we will present the most important news with a group of Italian colleagues and we will discuss how these results will impact the management of breast cancer

Recruitment of Oysters by Different Collection Devices at a Longline shellfish Farm in the Central Adriatic Sea

In 2020–2021, a trial to recruit flat oysters was implemented at a longline farm in the central Adriatic, whereby the efficiency recruitment (n. oyster/dm2) of different suspended substrates was evaluated. Two lantern nets (50 cm diameter; 145 cm h) had different substrates composed of 8 mm wide wrinkled ribbon and empty oyster shells positioned in the upper levels of the lanterns. The tumbling evaluation and the presence of mud were also considered. The efficiency recruitment was similar between the wrinkled ribbon and the oyster shell. Recruitment was in the same proportion on the external rough part of the shells as on the internal smooth part of the shells. No significant differences were shown when comparing the different substrates in terms of recruitment efficiency

Identification of a prognostic signature based on the expression of genes related to the insulin pathway in early breast cancer

INTRODUCTION: Insulin and the insulin-like growth factor (IGF) family play a key role in breast cancer (BC). OBJECTIVE: In this study, we evaluated on a genomic scale the potential prognostic value of insulin signaling in early BC. METHODS: Candidate genes were selected from the published literature and gene expression profiling experiments. Three publicly available BC datasets, containing gene expression data on 502 cases, were used to test the prognostic ability of the score. The gene signature was developed on GSE1456, containing microarray data from 159 patients, split into a training set (102 breast tumors) and a validation set (n = 57). GSE3494 and GSE2990 (350 patients) were used for external validation. Univariate Mann-Whitney test was used to identify genes differentially expressed between relapsed and nonrelapsed patients. Expression of genes significantly correlated with relapse was combined in a linear score. Patients were classified as low or high risk with respect to the median value. RESULTS: On the training set, 15 genes turned out to be differentially expressed: 8-year disease-free survival (DFS) was 51 and 91% in the high- and low-risk group (p < 0.001), respectively. In the validation set, DFS was 97 and 54% (p = 0.009), respectively. External validation: 8-year DFS was 72 and 61%, respectively, in GSE3494 (p = 0.03) and 74 and 55% in GSE2990 (p = 0.03). By multivariate analyses, the insulin signature was significantly associated with DFS, independently of age, hormone receptor status, nodal status, and grade. CONCLUSIONS: Our findings indicate that the insulin pathway is involved in BC prognosis at a genomic level and provide a window of selectivity for preventive and treatment strategies targeting the insulin/IGF pathway in BC patients