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BACKGROUND: The technical development of imaging techniques in life sciences has enabled the three-dimensional recording of living samples at increasing temporal resolutions. Dynamic 3D data sets of developing organisms allow for time-resolved quantitative analyses of morphogenetic changes in three dimensions, but require efficient and automatable analysis pipelines to tackle the resulting Terabytes of image data. Particle image velocimetry (PIV) is a robust and segmentation-free technique that is suitable for quantifying collective cellular migration on data sets with different labeling schemes. This paper presents the implementation of an efficient 3D PIV package using the Julia programming language-quickPIV. Our software is focused on optimizing CPU performance and ensuring the robustness of the PIV analyses on biological data. RESULTS: QuickPIV is three times faster than the Python implementation hosted in openPIV, both in 2D and 3D. Our software is also faster than the fastest 2D PIV package in openPIV, written in C++. The accuracy evaluation of our software on synthetic data agrees with the expected accuracies described in the literature. Additionally, by applying quickPIV to three data sets of the embryogenesis of Tribolium castaneum, we obtained vector fields that recapitulate the migration movements of gastrulation, both in nuclear and actin-labeled embryos. We show normalized squared error cross-correlation to be especially accurate in detecting translations in non-segmentable biological image data. CONCLUSIONS: The presented software addresses the need for a fast and open-source 3D PIV package in biological research. Currently, quickPIV offers efficient 2D and 3D PIV analyses featuring zero-normalized and normalized squared error cross-correlations, sub-pixel/voxel approximation, and multi-pass. Post-processing options include filtering and averaging of the resulting vector fields, extraction of velocity, divergence and collectiveness maps, simulation of pseudo-trajectories, and unit conversion. In addition, our software includes functions to visualize the 3D vector fields in Paraview.
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Imageamento Tridimensional , Software , Desenvolvimento Embrionário , Processamento de Imagem Assistida por Computador , ReologiaRESUMO
BACKGROUND: The Lifestyle-Integrated Functional Exercise (LiFE) program is effective in improving strength, balance, and physical activity (PA) while simultaneously reducing falls in older people by incorporating exercise activities in recurring daily tasks. However, implementing the original LiFE program includes substantial resource requirements. Therefore, as part of the LiFE-is-LiFE project, a group format (gLiFE) of the LiFE program has been developed, which will be tested regarding its noninferiority to the individually delivered LiFE in terms of PA-adjusted fall incidence and overall cost-effectiveness. METHODS: In a multi-centre, single-blinded noninferiority trial, an envisaged sample of N = 300 participants (> 70 years; faller and/or confirmed falls risk; community-dwelling) will be randomized in either LiFE or gLiFE. Both groups will undergo the same strength and balance activities as well as PA promotion activities and habitualization strategies as described in the LiFE programme, however, based on different approaches of delivery: During the 6-month intervention phase, LiFE participants will receive seven home visits and two telephone calls; in gLiFE, the program will be delivered in seven group sessions and also two telephone calls. Main outcomes are a) fall incidence per PA and b) incremental cost-effectiveness ratio comparing costs and quality-adjusted life years between the two interventions. Secondary outcomes include PA behaviour, motor performance, health status, psychosocial status, program evaluation, and adherence. Measurements will be conducted at baseline, 6-month and 12-month follow-up; evaluation of intervention sessions and assessment of psychosocial variables related to execution and habitualization of LiFE activities will be made during the intervention period as well. DISCUSSION: Compared to LiFE, we expect gLiFE to (a) reduce falls per PA by a similar rate; (b) be more cost-effective; (c) comparably enhance physical performance in terms of strength and balance as well as PA. By investigating the economic and societal benefit, this study will be of high practical relevance as noninferiority of gLiFE would facilitate large-scale implementation due to lower resource usage. This would result in better reach and increased accessibility, which is important for subjects with a history of falls and/or being at risk of falls. TRIAL REGISTRATION: ClinicalTrials.gov NCT03462654 . Registered on March 12, 2018.
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Acidentes por Quedas/prevenção & controle , Terapia por Exercício/métodos , Exercício Físico/psicologia , Vida Independente , Estilo de Vida , Atividade Motora/fisiologia , Anos de Vida Ajustados por Qualidade de Vida , Acidentes por Quedas/economia , Acidentes por Quedas/estatística & dados numéricos , Idoso , Análise Custo-Benefício , Terapia por Exercício/economia , Feminino , Humanos , Masculino , Método Simples-CegoRESUMO
For diploid model organisms, the actual transgenesis processes require subsequent periods of transgene management, which are challenging in emerging model organisms due to the lack of suitable methodology. We used the red flour beetle Tribolium castaneum, a stored-grain pest, to perform a comprehensive functional evaluation of our AClashOfStrings (ACOS) and the combined AGameOfClones/AClashOfStrings (AGOC/ACOS) vector concepts, which use four clearly distinguishable markers to provide full visual control over up to two independent transgenes. We achieved comprehensive statistical validation of our approach by systematically creating seventeen novel single and double homozygous sublines intended for fluorescence live imaging, including several sublines in which the microtubule cytoskeleton is labeled. During the mating procedures, we genotyped more than 20,000 individuals in less than 80 working hours, which corresponds to about 10 to 15â s per individual. We also confirm the functionality of our combined concept in two double transgene special cases, i.e. integration of both transgenes in close proximity on the same chromosome and integration of one transgene on the X allosome. Finally, we discuss our vector concepts regarding performance, genotyping accuracy, throughput, resource saving potential, fluorescent protein choice, modularity, adaptation to other diploid model organisms and expansion capability.
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Tribolium , Animais , Animais Geneticamente Modificados , Homozigoto , Organismos Geneticamente Modificados , Genótipo , Tribolium/genética , Tribolium/metabolismoRESUMO
Senescence is an important consequence of cytostatic drug-based tumor therapy. Here we analyzed to which degree the anticancer drug oxaliplatin induces cell death, cell cycle arrest, and senescence in colorectal cancer (CRC) cells and elucidated the role of p53. Oxaliplatin treatment resulted in the G2-phase arrest in all CRC lines tested (HCT116p53+/+, HCT116p53-/-, LoVo, SW48 and SW480). Immunoblot analysis showed that within the p53-competent lines p53 and p21CIP1 are activated at early times upon oxaliplatin treatment. However, at later times, only LoVo cells showed sustained activation of the p53/p21CIP1 pathway, accompanied by a strong induction of senescence as measured by senescence-associated ß-Gal staining and induction of senescence-associated secretory phenotype (SASP) factors. Opposite to LoVo, the p53/p21CIP1 response and senescence induction was much weaker in the p53-proficient SW48 and SW480 cells, which was due to deficiency for p14ARF. Thus, among lines studied only LoVo express p14ARF protein and siRNA-mediated knockdown of p14ARF significantly reduced sustained p53/p21CIP1 activation and senescence. Vice versa, ectopic p14ARF expression enhanced oxaliplatin-induced senescence in SW48 and SW480 cells. Our data show that oxaliplatin-induced senescence in CRC cells is dependent on p53 proficiency; however, a significant induction can only be observed upon p14ARF-mediated p53 stabilization.
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Light sheet-based fluorescence microscopy offers efficient solutions to study complex processes on multiple biologically relevant scales. Sample chamber-based setups, which are specifically designed to preserve the three-dimensional integrity of the specimen and usually feature sample rotation, are the best choice in developmental biology. For instance, they have been used to document the entire embryonic morphogenesis of the fruit fly Drosophila melanogaster and the red flour beetle Tribolium castaneum. However, many available live imaging protocols provide only experimental frameworks for single embryos. Especially for comparative studies, such approaches are inconvenient, since sequentially imaged specimens are affected by ambient variance. Further, this limits the number of specimens that can be assayed within a given time. We provide an experimental framework for simultaneous live imaging that increases the throughput in sample chamber-based setups and thus ensures similar ambient conditions for all specimens. Firstly, we provide a calibration guideline for light sheet fluorescence microscopes. Secondly, we propose a mounting method for multiple embryos that is compatible with sample rotation. Thirdly, we provide exemplary three-dimensional live imaging datasets of Drosophila, for which we juxtapose three transgenic lines with fluorescently labeled nuclei, as well as of Tribolium, for which we compare the performance of three transgenic sublines that carry the same transgene, but at different genomic locations. Our protocol is specifically designed for comparative studies as it pro-actively addresses ambient variance, which is always present in sequential live imaging. This is especially important for quantitative analyses and characterization of aberrational phenotypes, which result e.g., from knockout experiments. Further, it increases the overall throughput, which is highly convenient when access to light sheet fluorescence microscopes is limited. Finally, the proposed mounting method can be adapted for other insect species and further model organisms, e.g., zebrafish, with basically no optimization effort.
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Drosophila melanogaster/embriologia , Embrião não Mamífero/diagnóstico por imagem , Imageamento Tridimensional , Microscopia de Fluorescência/métodos , Tribolium/embriologia , Animais , Animais Geneticamente Modificados , Calibragem , Análise de Dados , Desenvolvimento Embrionário , Hipoclorito de SódioRESUMO
BACKGROUND: The Lifestyle-integrated Functional Exercise (LiFE) programme is a fall prevention programme originally taught in a resource-intensive one-to-one format with limited feasibility for large-scale implementation. The aim of this paper is to present the conceptual framework and initial feasibility evaluation of a group-based LiFE (gLiFE) format developed for large-scale implementation. METHODS: The conceptual gLiFE framework (part I) is based on three pillars, LiFE Activities and Principles, Theory of Behaviour Change and Behaviour Change Techniques, and Instruction. The feasibility of gLiFE was tested (part II) within a multimodal approach including quantitative questionnaires measuring safety, acceptability (1 = best to 7 = insufficient), and adherence to the LiFE activities (range = 0-14) as well as a focus group interview. Exploratory self-reported measures on behaviour change including self-determined motivation (range = 1-5), intention, planning, action control, and habit strength (range = 1-6) were assessed pre and post intervention. Data analyses were performed using descriptive statistics and qualitative content analysis. RESULTS: The development process resulted in a manualised gLiFE concept containing standardised information on gLiFE's content and structure. Feasibility testing: Six older adults (median = 72.8 years, 5 female) completed the feasibility study and rated safety (median = 7.0, IQR = 0.3) and acceptability as high (median = 1, IQR = 1). Participants implemented 9.5 LiFE activities (IQR = 4.0) into their daily routines. No adverse events occurred during the study. In the focus group, the group format and LiFE activities were perceived as positive and important for maintaining strength and balance capacity. Self-determined motivation intention, planning, and habit strength were rated higher post intervention. CONCLUSION: The developed conceptual gLiFE framework represents the basis for a gLiFE format with potential for standardised large-scale implementation. Proof-of-concept could be demonstrated in a group of community-dwelling older adults at risk of falling. The public health potential of gLiFE in terms of (cost-)effectiveness is currently being evaluated in a large trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03412123. Registered on January 26, 2018.
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Isoflavonoids and fish oil may be protective against colorectal cancer, but the evidence in relation to breast cancer risk is ambiguous. In the present study, we have investigated the impact of soya-derived isoflavonoids and n-3 fatty acids from fish oil, both individually and in combination, on apoptosis, cell proliferation and oestrogen receptor (ER) expression in the colon and mammary gland of the rat. Female rats were fed diets high in n-3 fatty acids (80 g/kg diet) or soya protein (765 mg/kg diet isoflavones) for 2 weeks, and then killed before the removal of the colon and mammary glands. Cell proliferation and apoptosis were quantified morphologically in whole crypts and terminal end buds. The expressions of ERalpha and ERbeta were measured in colon tissue scrapes and the mammary gland. Fish oil significantly increased apoptosis and decreased mitosis in both tissues, an effect associated with a decrease in the expressions of ERalpha and ERbeta. Soya had no effect on apoptosis in either tissue, but reduced mitosis in the colon (P < 0.001) while increasing it in the mammary gland (P = 0.001). The changes in proliferation were associated with contrasting changes in the ER expression such that fish oil significantly decreased both ERbeta and ERalpha, while soya increased ERalpha and decreased ERbeta. The results may provide a novel mechanism by which n-3 fatty acids could reduce cancer risk, but the interpretation of the results in relation to soya consumption and breast cancer risk requires further investigation.
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Colo/efeitos dos fármacos , Óleos de Peixe/administração & dosagem , Mucosa Intestinal/citologia , Isoflavonas/administração & dosagem , Glândulas Mamárias Animais/citologia , Proteínas de Soja/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colo/citologia , Colo/metabolismo , Receptor alfa de Estrogênio/análise , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/análise , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Ciclo Estral , Feminino , Expressão Gênica , Mucosa Intestinal/metabolismo , Isoflavonas/sangue , Glândulas Mamárias Animais/metabolismo , RNA/análise , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Proteínas de Soja/sangueRESUMO
Axonal damage is a major factor contributing to disease progression in multiple sclerosis (MS) patients. On the histological level, acute axonal injury is most frequently analyzed by anti-amyloid precursor protein immunohistochemistry. To what extent this method truly detects axonal injury, and whether other proteins and organelles are as well subjected to axonal transport deficits in demyelinated tissues is not known. The aim of this study was to correlate ultrastructural morphology with the immunohistochemical appearance of acute axonal injury in a model of toxin-induced oligodendrocyte degeneration. C57BL/6J mice were intoxicated with 0.25% cuprizone to induce demyelination. The corpus callosum was investigated by serial block-face scanning electron microscopy (i.e., 3D EM), immunohistochemistry, and immunofluorescence microscopy. Brain tissues of progressive MS patients were included to test the relevance of our findings in mice for MS. Volumes of axonal swellings, determined by 3D EM, were comparable to volumes of axonal spheroids, determined by anti-APP immunofluorescence stains. Axonal swellings were present at myelinated and non-myelinated axonal internodes. Densities of amyloid precursor protein (APP)+ spheroids were highest during active demyelination. Besides APP, vesicular glutamate transporter 1 and mitochondrial proteins accumulated at sites of axonal spheroids. Such accumulations were found as well in lesions of progressive MS patients. In this correlative ultrastructural-immunohistochemical study, we provide strong evidence that breakdown of the axonal transport machinery results in focal accumulations of mitochondria and different synaptic proteins. We provide new marker proteins to visualize acute axonal injury, which helps to further understand the complex nature of axonal damage in progressive MS.
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Transporte Axonal , Axônios/ultraestrutura , Animais , Biomarcadores/metabolismo , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Humanos , Imuno-Histoquímica , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Mitocondriais/metabolismo , Esclerose Múltipla/patologia , Bainha de Mielina/patologia , Bainha de Mielina/ultraestrutura , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/metabolismo , Esferoides Celulares/metabolismoRESUMO
MPP4 and MPP5 are closely related members of the p55-subfamily of membrane-associated guanylate kinases (MAGUKs) known to mediate the assembly of protein complexes at the plasma membrane of cell-cell junctions. Both MPP4 and MPP5 have been implicated in retinal function; however, their specific roles in the cellular mechanisms underlying vision are largely unknown. Here, we generated specific poly- and monoclonal antibodies against the two proteins and show that MPP4 and MPP5 are localized at distinct sites of cell-cell contact in the mouse retina. While MPP4 is a component of the synaptic terminals of photoreceptors, MPP5 exclusively localizes to apical membrane domains of the outer limiting membrane (OLM) junctions. The vertebrate homologs of Caenorhabditis elegans lin-7, Veli1, -2, and -3, have previously been identified as putative binding partners of MPP5. In this study, we show that MPP4 directly interacts with the Veli proteins via L27 heterodimerization in vitro. In addition, two of the three Veli isoforms, Veli1 and -3, are demonstrated to be expressed in the mouse retina. Immunofluorescence microscopy reveals extensive colocalization of Veli3 with both MPP4 and MPP5. This association of Veli3 with either MPP4 or MPP5 suggests that the MAGUKs recruit Veli3 and its binding partners to different cellular regions of the retina where they may participate in the organization of specialized intercellular junctions.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Junções Intercelulares/metabolismo , Proteínas de Membrana/metabolismo , Núcleosídeo-Fosfato Quinase/metabolismo , Retina/metabolismo , Fatores Etários , Animais , Bovinos , Guanilato Quinases , Humanos , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/metabolismo , Neurônios/metabolismo , Células Fotorreceptoras/metabolismo , Isoformas de Proteínas , Retina/citologia , Retina/crescimento & desenvolvimento , Suínos , Sinapses/metabolismo , Distribuição TecidualRESUMO
PURPOSE: To perform a detailed morphologic and functional evaluation of Best macular dystrophy (BMD) associated with mutations in the VMD2 gene. DESIGN: Retrospective study. PARTICIPANTS: The records of 16 patients with BMD and heterozygous VMD2 mutations (group 1) and 5 patients with Best-like lesions with no detectable disease-associated alterations in the VMD2 gene (group 2) were evaluated retrospectively. METHODS: The data were reviewed regarding visual acuity (VA), color vision, perimetry, autofluorescence of the retinal pigment epithelium (RPE), fluorescein angiography, electro-oculography (EOG), and full-field electroretinography (ERG) and multifocal ERG (mfERG). MAIN OUTCOME MEASURES: VMD2 mutations, age at onset of BMD, RPE autofluorescence, EOG, ERG, and mfERG. RESULTS: The mean age of the patients in group 1 was 47.1 years (range, 16.7-86.5), and age at onset varied between 5 and 58 years (median, 42.0). Visual acuity ranged between 20/16 and 20/400 (median, 20/40). No association existed between the specific nature of the VMD2 mutation and disease onset or expressivity. Retinal pigment epithelium autofluorescence was increased corresponding to ophthalmoscopically visible yellow material, whereas it was decreased in the atrophic stage of BMD. Electro-oculography light rise was reduced in 18 of 19 eyes. Electroretinography amplitudes were normal in 3 patients and reduced in 6 patients. Multifocal ERG revealed in 10 of 20 eyes a central amplitude reduction and in 7 eyes a generalized one. There were no marked differences in clinical and functional findings between the patients in groups 1 and 2, except that the mean age of the patients in group 2 was higher (64.0 years [range, 45.7-80.6]) and the median VA lower (20/50 [range, 20/32-20/320]). CONCLUSIONS: The onset of BMD is highly variable and occurred in the majority of patients after the second decade of life. Best-like lesions may develop in older patients without associated VMD2 mutations. Those manifestations may be related to a specific form of age-related macular degeneration. This article contains additional online-only material available at .
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Proteínas do Olho/genética , Degeneração Macular/genética , Mutação , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Bestrofinas , Canais de Cloreto , Percepção de Cores , Eletroculografia , Eletrorretinografia , Feminino , Angiofluoresceinografia , Humanos , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acuidade Visual , Testes de Campo VisualRESUMO
Mutations in the vitelliform macular dystrophy 2 (VMD2) gene encoding besrtophin are responsible for Best macular dystrophy (BMD), a juvenile-onset autosomal dominant disorder of the central retina. Here, we report ten novel VMD2 mutations identified in clinically diagnosed BMD patients. The heterozygous alterations include nine missense mutations (c.32A>T, c.76G>C, c.85T>C, c.122T>C, c.122T>C, c.310G>C, c.722C>A, c.880C>G, c.893T>C) resulting in amino acid changes (respectively: Asn11Ile, Gly26Arg, Tyr29His, Leu41Pro, Trp102Arg, Asp104His, Thr241Asn, Leu294Val and Phe298Ser) located within four previously defined hotspot regions of the gene. In addition, a silent exonic mutation (c.624G>A) was identified in a two generation BMD pedigree. To determine a possible pathogenic effect of this variant, the consequences on splicing behaviour and potential exonic splice enhancer (ESE) motifs were analyzed. Finally, a 1-bp deletion (c.779delC) resulting in a frameshift mutation (Pro260fsX288) was found in exon 7, representing the first case of a potential frameshift mutation that affects the N-terminal half of the VMD2 protein. Besides a dominant negative effect which is likely attributable to the identified missense mutations, the deletion mutation suggests haploinsufficiency as an infrequent disease-causing mechanism in BMD.
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Proteínas do Olho/genética , Degeneração Macular/genética , Mutação , Bestrofinas , Canais de Cloreto , Análise Mutacional de DNA , Variação Genética , Humanos , Polimorfismo Genético , Splicing de RNARESUMO
Li-Fraumeni Syndrome (LFS) is a rare cancer syndrome caused by mutations in the TP53 gene. A number of tumor-associated germline mutations have been described in individuals from various ethnic origins although, thus far, none in affected individuals of German descent. Our work aimed to detect germline mutations in the TP53 gene in five index cases of German and Swiss origin with cancers typical of Li-Fraumeni syndrome. We analyzed all ten coding exons of the TP53 gene by direct sequencing of PCR products. We identified five mutations of which three were found in families with a strong history of LFS in several generations while two likely came about de novo. The five mutations include two missense mutations in exon 4 (Gly105Cys) and exon 7 (Arg248Gln), one deletion of 11 base pairs encompassing the splice acceptor sequence of exon 6 (IVS5-11_-1 del), one nonsense mutation in exon 6 (Arg196Stop), and one duplication of 4 base pairs in exon 8 (1020_1023dupCTGC). The functional consequence of the IVS5-11_-1del mutation on splicing of pre-mRNA was investigated by an in vitro assay. Our study reports the first germline mutations in patients of German and Swiss origin with LFS-related tumors. The frequent identification of de novo germline mutations emphasizes the importance of mutational analyses of the TP53 gene particularly in young patients with malignancies typical for LFS, but without a positive family history of this tumor syndrome.
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Genes p53/genética , Síndrome de Li-Fraumeni/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Mutação em Linhagem Germinativa , Alemanha , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Linhagem , Sítios de Splice de RNA , SuíçaRESUMO
The aim of the present study was to investigate the effect of in utero administration of coumestrol, equol, and selenium-enriched yeast on selected hepatic phase 2 enzymes, plasma hormone levels, and markers for redox status in plasma and red blood cells (RBCs). The test compounds were administered via the diet to pregnant Sprague-Dawley rats throughout gestation. Within 24 h following delivery dams and offspring were sacrificed, and blood, liver, and reproductive organs were sampled. Coumestrol, equol, and selenium-enriched yeast did not significantly affect hepatic glutathione S-transferase (GST), quinone reductase (QR), or RBC glutathione peroxidase (GPx) in the offspring, whereas significant increases in GST, QR, and GPx activities in dams were observed following administration of selenium-enriched yeast. The level of 17beta-estradiol in offspring from coumestrol-exposed dams was significantly increased compared with the control. The present results indicate that selenium-enriched yeast, coumestrol, and equol affect selected hepatic phase 2 enzymes and GPx in RBC in dams, whereas the offspring in general were refractive to the employed treatments. Further studies are warranted to investigate whether the observed in utero effects imposed by the selected plant compounds confer permanent alterations on the health status of the animal resulting in an altered resistance to cancer.