piggyBac is an effective tool for functional analysis of the Plasmodium falciparum genome

<p>Abstract</p> <p>Background</p> <p>Much of the <it>Plasmodium falciparum </it>genome encodes hypothetical proteins with limited homology to other organisms. A lack of robust tools for genetic manipulation of the parasite limits functional analysis of these hypothetical proteins and other aspects of the <it>Plasmodium </it>genome. Transposon mutagenesis has been used widely to identify gene functions in many organisms and would be extremely valuable for functional analysis of the <it>Plasmodium </it>genome.</p> <p>Results</p> <p>In this study, we investigated the lepidopteran transposon, <it>piggyBac</it>, as a molecular genetic tool for functional characterization of the <it>Plasmodium falciparum </it>genome. Through multiple transfections, we generated 177 unique <it>P. falciparum </it>mutant clones with mostly single <it>piggyBac </it>insertions in their genomes. Analysis of <it>piggyBac </it>insertion sites revealed random insertions into the <it>P. falciparum </it>genome, in regards to gene expression in parasite life cycle stages and functional categories. We further explored the possibility of forward genetic studies in <it>P. falciparum </it>with a phenotypic screen for attenuated growth, which identified several parasite genes and pathways critical for intra-erythrocytic development.</p> <p>Conclusion</p> <p>Our results clearly demonstrate that <it>piggyBac </it>is a novel, indispensable tool for forward functional genomics in <it>P. falciparum </it>that will help better understand parasite biology and accelerate drug and vaccine development.</p

Single-cell transcriptional atlas of human breast cancers and model systems

BACKGROUND: Breast cancer's complex transcriptional landscape requires an improved understanding of cellular diversity to identify effective treatments. The study of genetic variations among breast cancer subtypes at single-cell resolution has potential to deepen our insights into cancer progression. METHODS: In this study, we amalgamate single-cell RNA sequencing data from patient tumours and matched lymph metastasis, reduction mammoplasties, breast cancer patient-derived xenografts (PDXs), PDX-derived organoids (PDXOs), and cell lines resulting in a diverse dataset of 117 samples with 506 719 total cells. These samples encompass hormone receptor positive (HR+), human epidermal growth factor receptor 2 positive (HER2+), and triple-negative breast cancer (TNBC) subtypes, including isogenic model pairs. Herein, we delineated similarities and distinctions across models and patient samples and explore therapeutic drug efficacy based on subtype proportions. RESULTS: PDX models more closely resemble patient samples in terms of tumour heterogeneity and cell cycle characteristics when compared with TNBC cell lines. Acquired drug resistance was associated with an increase in basal-like cell proportions within TNBC PDX tumours as defined with SCSubtype and TNBCtype cell typing predictors. All patient samples contained a mixture of subtypes; compared to primary tumours HR+ lymph node metastases had lower proportions of HER2-Enriched cells. PDXOs exhibited differences in metabolic-related transcripts compared to PDX tumours. Correlative analyses of cytotoxic drugs on PDX cells identified therapeutic efficacy was based on subtype proportion. CONCLUSIONS: We present a substantial multimodel dataset, a dynamic approach to cell-wise sample annotation, and a comprehensive interrogation of models within systems of human breast cancer. This analysis and reference will facilitate informed decision-making in preclinical research and therapeutic development through its elucidation of model limitations, subtype-specific insights and novel targetable pathways. KEY POINTS: Patient-derived xenografts models more closely resemble patient samples in tumour heterogeneity and cell cycle characteristics when compared with cell lines. 3D organoid models exhibit differences in metabolic profiles compared to their in vivo counterparts. A valuable multimodel reference dataset that can be useful in elucidating model differences and novel targetable pathways

A case of child survivor of family trauma: creating a safe place, building strengths through play

Young children living in dysfunctional households marked with high levels of interparental domestic violence are at higher risk for developing future psychiatric disorders and overall health problems. Successful treatment interventions with this group are varied, although existing research highlights the need for treatments that adopt a strength-based approach, that promote safety, and that nurture interpersonal relationships. Child-centred play therapy provides the client with a sense of empowerment and is described in this chapter

Associação entre as condutas de risco do uso de álcool e sexo desprotegido em adolescentes numa cidade do Sul do Brasil

This paper aims to analyze alcohol abuse and unprotected sex and the association between them in students in a city in the southern region of Brazil. This is a cross-sectional study using a quantitative approach with 590 secondary school students from two public schools. Regarding alcohol use, 14% scored from eight to 40 in The Alcohol Use Disorders Identification Test (AUDIT), which means, at least, a risky drinking behavior, with higher rate among boys. Moreover, 31.1% indulged themselves in binge drinking, which means drinking six or more doses according to AUDIT; and even among those who are low-risk drinkers, 21.1% had this drinking pattern. Regarding sexual behavior, young boys started sexual life earlier and the kind of relationship more referred to by them is one with no commitment; boys have uncommitted relationships, while girls have more relationships with commitment. In relation to the results of the association between alcohol use and sexual intercourse, 47.3% stated alcohol use before having sex, and those who started sexual activity got more drunk and had higher scores in the AUDIT. New studies are recommended regarding the association between both behaviors in Brazil, considering that the causal relationship is not clear and shows several explanation models

Effluents quality during the grow-out phase of the amazon shrimp macrobrachium amazonicum

In recent years shrimp culture farms have been one of the most growing sectors in aquaculture. Research has been carried out in order to establish a sustainable production maintaining profit and low environmental impact. Current investigation analyzed source and effluent water produced during the final grow-out phase of the Amazon shrimp (Macrobrachium amazonicum). Twelve natural-bottom ponds, with continuous water flow and stock density comprising 40, 60, 80 and 100 young shrimps/m2 were analyzed. The experiment design comprised totally randomized blocks with four treatments and three replications. Microbiological analyses for Escherichia coli was attempted, coupled to physical and chemical analyses for pH, temperature, total suspended solids, total nitrogen, nitrite, nitrate, biochemical oxygen demand and chemical oxygen demand of water supply and pond effluents. Results show that whereas effluent quality complied with current legal rules, there was no significant difference between supply and effluent water for the analyzed variables and between stock densities. Under the conditions investigated and the intensification of culture in the final grow-out phase up to a density of 100 young shrimps/m2, the production of M. amazonicum reveals low potential for environmental impact for the variables analyzed