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Abstract Background The ideal malaria parasite populations for initial mapping of genomic regions contributing to phenotypes such as drug resistance and virulence, through genome-wide association studies, are those with high genetic diversity, allowing for numerous informative markers, and rare meiotic recombination, allowing for strong linkage disequilibrium (LD) between markers and phenotype-determining loci. However, levels of genetic diversity and LD in field populations of the major human malaria parasite P. vivax remain little characterized. Results We examined single-nucleotide polymorphisms (SNPs) and LD patterns across a 100-kb chromosome segment of P. vivax in 238 field isolates from areas of low to moderate malaria endemicity in South America and Asia, where LD tends to be more extensive than in holoendemic populations, and in two monkey-adapted strains (Salvador-I, from El Salvador, and Belem, from Brazil). We found varying levels of SNP diversity and LD across populations, with the highest diversity and strongest LD in the area of lowest malaria transmission. We found several clusters of contiguous markers with rare meiotic recombination and characterized a relatively conserved haplotype structure among populations, suggesting the existence of recombination hotspots in the genome region analyzed. Both silent and nonsynonymous SNPs revealed substantial between-population differentiation, which accounted for ~40% of the overall genetic diversity observed. Although parasites clustered according to their continental origin, we found evidence for substructure within the Brazilian population of P. vivax. We also explored between-population differentiation patterns revealed by loci putatively affected by natural selection and found marked geographic variation in frequencies of nucleotide substitutions at the pvmdr-1 locus, putatively associated with drug resistance. Conclusion These findings support the feasibility of genome-wide association studies in carefully selected populations of P. vivax, using relatively low densities of markers, but underscore the risk of false positives caused by population structure at both local and regional levels. See commentary: http://www.biomedcentral.com/1741-7007/8/90

Abstract Background Fructose-based diets are apparently related to the occurrence of several metabolic dysfunctions, but the effects of the consumption of high amounts of fructose on body tissues have not been well described. The aim of this study was to analyze the general characteristics and the lipid content of different tissues of rats after chronic ingestion of a fructose rich soft drink. Methods Forty-five Wistar rats were used. The rats were divided into three groups (n = 15) and allowed to consume water (C), light Coca Cola ® (L) or regular Coca Cola® (R) as the sole source of liquids for eight weeks. Results The R group presented significantly higher daily liquid intake and significantly lower food intake than the C and L groups. Moreover, relative to the C and L groups, the R group showed higher triglyceride concentrations in the serum and liver. However, the L group animals presented lower values of serum triglycerides and cholesterol than controls. Conclusions Based on the results, it can be concluded that daily ingestion of a large amount of fructose- rich soft drink resulted in unfavorable alterations to the lipid profile of the rats.

Introduction: We investigated whether novel plasma biomarkers are associated with cognition, cognitive decline, and functional independence in activities of daily living across and within neurodegenerative diseases., Methods: Glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), phosphorylated tau (p-tau)181 and amyloid beta (Aβ) 42/40 were measured using ultra-sensitive Simoa immunoassays in 44 healthy controls and 480 participants diagnosed with Alzheimer's disease/mild cognitive impairment (AD/MCI), Parkinson's disease (PD), frontotemporal dementia (FTD) spectrum disorders, or cerebrovascular disease (CVD)., Results: GFAP, NfL, and/or p-tau181 were elevated among all diseases compared to controls, and were broadly associated with worse baseline cognitive performance, greater cognitive decline, and/or lower functional independence. While GFAP, NfL, and p-tau181 were highly predictive across diseases, p-tau181 was more specific to the AD/MCI cohort. Sparse associations were found in the FTD and CVD cohorts and for Aβ 42/40 ., Discussion: GFAP, NfL, and p-tau181 are valuable predictors of cognition and function across common neurodegenerative diseases, and may be useful in specialized clinics and clinical trials., (© 2023 The Authors. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Demand for more environmentally friendly practices have led to the adoption of several feed supplements by the fish farming industry. In the present study, we investigated a commercially available formula that includes a mixture of three compounds: organic acids, a phytochemical and Biomin® Permeabilizing Complex. This mixture demonstrated antimicrobial properties in vitro and was able to inhibit growth of multiple species of aquatic bacterial pathogens, including Aeromonas salmonicida. Bacterial challenge was performed using A. salmonicida and three exposure routes: intra-peritoneal injection, immersion, and cohabitation. Mortality rates following infection by injection were significantly decreased in the fish that had received the supplemented feed. Fish infected through the other routes did not show a significant difference in mortality. In term of farming performance, while the fish that had received the feed supplement showed an improvement in weight gain and final weight, these changes were not found to be statistically significant. Similarly, no significant difference was observed in the feed conversion ratio. The results of this study suggest that this feed supplement may be effective at protecting rainbow trout from fish furunculosis., (Copyright © 2017. Published by Elsevier Ltd.)

Intimate partner homicide/attempted homicide are the most serious outcome of intimate partner violence. Thus, in this study, conducted in Portugal, we sought to compare perpetrators of severe violence with those who perpetrate less severe acts of violence as well as to identify predictors for severe violence. Sample was constituted by 50 men convicted for marital homicide or attempted homicide and 137 men convicted for domestic violence. Results show that although both perpetrators of severe and less severe violence share some characteristics, significant differences were found among them. The use of weapons, separation/break-up, and high socioeconomic status (SES) significantly increased the likelihood of a man to commit severe violence. Prior violence, aggression, and medium SES decreased significantly the probability of an individual to perpetrate severe violence. These findings reinforce the assumption that severe and less severe forms of violence can be discrete phenomena and underscore the importance of conducting accurate risk assessments.

In the current study we reported cultivation, extraction procedure, analysis and preliminary characterization of the aqueous extract from Cereus peruvianus callus culture and evaluated its anti ulcerogenic activity in vivo models of experimental ulcers in Wistar rats. The obtained aqueous extract from callus (AC) was dialyzed and subjected to freeze-thaw process, providing a possible polysaccharide. The carbohydrate and protein contents of the aqueous extract were estimated at 53.4% and 0.66%, respectively, composed primarily of galactose, arabinose and galacturonic acid, with minor amounts of glucose. This appeared heterogeneous when analyzed by high-performance size-exclusion chromatography and a multiangle laser light scattering detector (HPSEC-MALLS). The AC was found to be significantly effective against ethanol-induced lesions but was ineffective against indomethacin-induced lesions. The callus culture of C. peruvianus is an alternative source for the synthesis of substances originally produced by plants. The calluses grown indefinitely in vitro under controlled conditions are stable tissues, and the aqueous extract from calluses may be used instead of fully developed plants using the protocols described in this study.

The topoisomerase I poison CPT-11 has proved efficient for the treatment of untreated metastatic colorectal cancers (CRC) and those refractory to fluoropyrimidines. However, the interpatient variability is important. A previous in vitro study suggested that measurements of the level of topoisomerase I-DNA intermediates trapped by camptothecin may be useful to estimate the chemosensitivity of colon carcinoma cell lines. To verify this hypothesis, we developed an immuno-assay to detect covalent topoisomerase I-DNA complexes in a series of human colorectal cancers xenografted in nude mice. Six human CRCs were selected for their distinctive p53 and microsatellite instability (MSI) status. Tumour lysates, prepared from mice untreated or treated with CPT-11, were fractionated onto CsCl gradients to separate free and DNA-bound topoisomerase I by centrifugation. Interestingly, significant levels of DNA-topoisomerase I complexes were detected in the tumours most responsive to the treatment with CPT-11, irrespective of their MSI and p53 phenotypes. Our in vivo study fully agrees with the predictions from the in vitro data indicating that evaluation of topoisomerase I-DNA complexes would be useful to predict the response of CRC to a treatment with CPT-11.