54 research outputs found

    Nuclear Reprogramming: Kinetics of Cell Cycle and Metabolic Progression as Determinants of Success

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    Establishment of totipotency after somatic cell nuclear transfer (NT) requires not only reprogramming of gene expression, but also conversion of the cell cycle from quiescence to the precisely timed sequence of embryonic cleavage. Inadequate adaptation of the somatic nucleus to the embryonic cell cycle regime may lay the foundation for NT embryo failure and their reported lower cell counts. We combined bright field and fluorescence imaging of histone H2b-GFP expressing mouse embryos, to record cell divisions up to the blastocyst stage. This allowed us to quantitatively analyze cleavage kinetics of cloned embryos and revealed an extended and inconstant duration of the second and third cell cycles compared to fertilized controls generated by intracytoplasmic sperm injection (ICSI). Compared to fertilized embryos, slow and fast cleaving NT embryos presented similar rates of errors in M phase, but were considerably less tolerant to mitotic errors and underwent cleavage arrest. Although NT embryos vary substantially in their speed of cell cycle progression, transcriptome analysis did not detect systematic differences between fast and slow NT embryos. Profiling of amino acid turnover during pre-implantation development revealed that NT embryos consume lower amounts of amino acids, in particular arginine, than fertilized embryos until morula stage. An increased arginine supplementation enhanced development to blastocyst and increased embryo cell numbers. We conclude that a cell cycle delay, which is independent of pluripotency marker reactivation, and metabolic restraints reduce cell counts of NT embryos and impede their development

    Recent intimate partner violence as a prenatal predictor of maternal depression in the first year postpartum among Latinas

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    The study aims to determine if recent intimate partner violence (IPV) is a prenatal risk factor for postpartum depression (PPD) among pregnant Latinas seeking prenatal care. A prospective observational study followed Latinas from pregnancy through 13 months postpartum. Prenatal predictors of PPD included depression, recent IPV exposure, remote IPV exposure, non-IPV trauma history, poverty, low social support, acculturation, high parity, and low education. Postpartum depression was measured at 3, 7, and 13 months after birth with the Beck's Depression Inventory—Fast Screen. Strength of association was evaluated using bivariate and multivariable odds ratio analysis. Subjects were predominantly low income, monolingual Spanish, and foreign-born, with mean age of 27.7. Recent IPV, prenatal depression, non-IPV trauma, and low social support were associated with greater likelihood of PPD in bivariate analyses. Recent IPV and prenatal depression continued to show significant association with PPD in multivariate analyses, with greater odds of PPD associated with recent IPV than with prenatal depression (adjusted OR = 5.38, p < 0.0001 for recent IPV and adjusted OR = 3.48, p< 0.0001 for prenatal depression). Recent IPV exposure is a strong, independent prenatal predictor of PPD among Latinas. Screening and referral for both IPV and PPD during pregnancy may help reduce postpartum mental health morbidity among Latinas

    Long-term efficacy of botulinum toxin A for treatment of blepharospasm,hemifacial spasm, and spastic entropion: a multicentre study using two drug-dose escalation indexes

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    PURPOSE: To investigate the long-term effectiveness and safety of botulinum neurotoxin A (BoNT-A) treatment in patients with blepharospasm (BEB), hemifacial spasm (HFS), and entropion (EN) and to use for the first time two modified indexes, 'botulin toxin escalation index-U' (BEI-U) and 'botulin toxin escalation index percentage' (BEI-%), in the dose-escalation evaluation. METHODS: All patients in this multicentre study were followed for at least 10 years and main outcomes were clinical efficacy, duration of relief, BEI-U and BEI-%, and frequency of adverse events. RESULTS: BEB, HFS, and EN patients received a mean BoNT-A dose with a significant inter-group difference (P<0.0005, respectively). The mean (+/-SD) effect duration was statistically different (P=0.009) among three patient groups. Regarding the BoNT-A escalation indexes, the mean (+/-SD) values of BEI-U and BEI-% were statistically different (P=0.035 and 0.047, respectively) among the three groups. In BEB patients, the BEI-% was significantly increased in younger compared with older patients (P=0.008). The most frequent adverse events were upper lid ptosis, diplopia, ecchymosis, and localized bruising. CONCLUSIONS: This long-term multicentre study supports a high efficacy and good safety profile of BoNT-A for treatment of BEB, HFS, and EN. The BEI indexes indicate a significantly greater BoNT-A-dose escalation for BEB patients compared with HFS or EN patients and a significantly greater BEI-% in younger vsolder BEB patients. These results confirm a greater efficacy in the elderly and provide a framework for long-term studies with a more flexible and reliable evaluation of drug-dose escalation

    Mitochondrial Physiology and Gene Expression Analyses Reveal Metabolic and Translational Dysregulation in Oocyte-Induced Somatic Nuclear Reprogramming

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    While reprogramming a foreign nucleus after somatic cell nuclear transfer (SCNT), the enucleated oocyte (ooplasm) must signal that biomass and cellular requirements changed compared to the nucleus donor cell. Using cells expressing nuclear-encoded but mitochondria-targeted EGFP, a strategy was developed to directly distinguish maternal and embryonic products, testing ooplasm demands on transcriptional and post-transcriptional activity during reprogramming. Specifically, we compared transcript and protein levels for EGFP and other products in pre-implantation SCNT embryos, side-by-side to fertilized controls (embryos produced from the same oocyte pool, by intracytoplasmic injection of sperm containing the EGFP transgene). We observed that while EGFP transcript abundance is not different, protein levels are significantly lower in SCNT compared to fertilized blastocysts. This was not observed for Gapdh and Actb, whose protein reflected mRNA. This transcript-protein relationship indicates that the somatic nucleus can keep up with ooplasm transcript demands, whilst transcription and translation mismatch occurs after SCNT for certain mRNAs. We further detected metabolic disturbances after SCNT, suggesting a place among forces regulating post-transcriptional changes during reprogramming. Our observations ascribe oocyte-induced reprogramming with previously unsuspected regulatory dimensions, in that presence of functional proteins may no longer be inferred from mRNA, but rather depend on post-transcriptional regulation possibly modulated through metabolism

    Interventions to control myopia progression in children: protocol for an overview of systematic reviews and meta-analyses.

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    Background Myopia is a common visual disorder with increasing prevalence among developed countries of the world. Myopia constitutes a substantial risk factor for several ocular conditions that can lead to blindness. The purpose of this study is to conduct an overview of systematic reviews and meta-analyses in order to identify and appraise robust research evidence regarding the management of myopia progression in children and adolescents. Methods A literature search will be conducted in MEDLINE, EMBASE, The Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effects (DARE), and Health Technology Assessment (HTA) Database via Centre for Reviews and Dissemination (CRD). We will search for systematic reviews or meta-analyses that examine optical or pharmaceutical modalities for myopia control. Two independent overview authors will screen the titles and abstracts against the eligibility criteria. Individual study’s methodological quality and quality of evidence for each outcome of interest will be assessed by two independent authors using the ROBIS tool and GRADE rating, respectively. In cases of disagreement, consensus will be reached with the help of a third author. Our primary outcomes will be the mean change in refractive error, mean axial length change, and adverse events. A citation matrix will be generated, and the corrected covered area (CCA) will be estimated, in order to identify overlapping primary studies. Possible meta-biases and measures of heterogeneity will be described, and cases of dual co-authorship will be identified and discussed. If any recently published randomized controlled trials (RCTs) are detected, these will be appraised and their findings will be presented. An overall summary of outcomes will be provided using descriptive statistics and will be supplemented by narrative synthesis. Discussion This overview will examine the high level of existing evidence for treatment of myopia progression. Efficient interventions will be identified, and side effects will be reported. The expected benefit is that all robust recent research evidence will be compiled in a single study. The results may inform future research in this area, which should provide insight into the appropriate regimes for the administration of these modalities and contribute to future guideline development

    Częstotliwość występowania gatunków Syrphidae (Diptera) w sadach jabłoniowych i na ich obrzeżach

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    The study was aimed at determining the attractiveness of neighbouring habitats for Syrphidae (Diptera). The frequency of Syrphidae occurrence in apple orchards and on their edges was studied in 2008–2010. A quality analysis of Syrphidae communities in apple orchards and surrounding habitats was performed. The studied orchards bordered on cultivated fields, shrubberies and a road overgrown with trees and bushes. In total 55 Syrphidae species were reported, which made up 13.9% of this family fauna in Poland, with 38 species recorded in the orchards and 49 species in their vicinity. Both in the orchards and in their edges the dominant were zoophagous species. The analysis of occurrence frequencies for the Syrphidae in orchards and their vicinity established that they were similar and at the same time higher than for all the other habitats except the orchard and the agricultural land bordering on it. All the habitats were dominated by two zoophages, namely Episyrphus balteatus (De Geer) and Eupeodes corollae (F.). The study proved that the plants of orchard edges constitutes a more attractive habitat for Syrphidae species than the orchard itself. The orchard edge habitats with abundant blooming greenery are the elements which attract Syrphidae more strongly than agricultural cultivations and which may determine the migration of those useful species onto orchards.Podjęte badania dotyczyły określenia atrakcyjności sąsiadujących ze sobą środowisk występowania w nich Syrhidae (Diptera). Badania nad częstotliwością występowania Syrphidae (Diptera) w sadach jabłoniowych i na ich obrzeżach prowadzono w latach 2008–2010. Dokonano analizy jakościowej Syrphidae występujących w sadach jabłoniowych i w środowiskach sąsiadujących z sadami. Obrzeżami sadów były uprawy rolnicze, zakrzewienia i droga porośnięta drzewami i krzewami. Stwierdzono łącznie 55 gatunków Syrphidae, które stanowiły 13,9% fauny krajowej tej rodziny. W sadach wystąpiło 38 gatunków, a na obrzeżach 49 gatunków. Zarówno w sadach, jak i na obrzeżach dominowały gatunki zoofagiczne. Przeanalizowano częstotliwość występowania gatunków Syrphidae w sadach i na ich obrzeżach i stwierdzono, że była ona podobna i równocześnie większa we wszystkich środowiskach z wyjątkiem sadu i graniczącego z nim pola uprawnego. We wszystkich środowiskach dominowały dwa zoofagi – Episyrphus balteatus (De Geer) i Eupeodes corollae (F.). Badania wykazały, że roślinność obrzeży sadu jest atrakcyjniejszym środowiskiem występowania gatunków Syrphidae niż sad. środowiska obrzeży sadu z bujną i kwitnącą roślinnością są elementami biocenoz zwabiającymi intensywniej Syrphidae niż uprawy polowe i mogą one decydować o przemieszczaniu się tych pożytecznych gatunków w uprawy sadownicze

    The phenology of occurrence of dominant predatory Syrphidae (Diptera) species in apple orchards and on their edges

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    The blooming wild plants in the vicinity of orchards may attract adult Syrphidae to these cultivations. Hence in 2008–2010 studies were conducted around Czempiń (western Wielkopolska) which covered the occurrence of the imagines of 5 dominant predatory Syrphidae species in apple orchards and on their edges. The phenology of Episyrphus balteatus (De Geer), Eupeodes corollae (F.), Melanostoma mellinum (L.), Sphaerophoria scripta (L.) and Syrphus vitripennis Meigen in apple orchards as well as in the neighbouring shrubberies and on the side of the road overgrown with trees and bushes was analysed. A greater abundance of imagines of the studied species was found on the edges than in the apple orchards. Also a preference for either orchards or their sides was indicated for Syrphidae, as they appeared in these biocenoses earlier or later, but not at the same time. A correlation between a mass catch of Syrphidae in the orchards and their edges was found. It was shown that the blooming plants of orchard edges, such as Tilia cordata, Symphoricarpos albus, Cirsium arvense and Galium aparine, could attract Syrphidae imagines to the orchards
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