84 research outputs found

    The ICSI procedure from past to future: a systematic review of the more controversial aspects

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    Background: ICSI is currently the most commonly used assisted reproductive technology, accounting for 70-80%of the cycles performed. This extensive use, even excessive, is partly due to the high level of standardization reached by the procedure. There are, however, some aspects that deserve attention and can still be ameliorated. The aim of this systematic review was to evaluate the results of available publications dealing with the management of specific situations during ICSI in order to support embryologists in trying to offer the best laboratory individualized treatment. Methods: This systematic review is based on material obtained by searching PUBMED between January 1996 and March 2015. We included peer-reviewed, English-language journal articles that have evaluated ICSI outcomes in the case of (i) immature oocytes, (ii) oocyte degeneration, (iii) timing of the various phases, (iv) polar body position during injection, (v) zona-free oocytes, (vi) fertilization deficiency, (vii) round-headed sperm, (viii) immotile sperm and (ix) semen samples with high DNA fragmentation. Results: More than 1770 articles were obtained, from which only 90 were specifically related to the issues developed for female gametes and 55 for the issues developed for male gametes. The studies selected for this review were organized in order to provide a guide to overcome roadblocks. According to these studies, the injection of rescue metaphase I oocytes should be discouraged due to poor clinical outcomes and a high aneuploidy rates; laser-assisted ICSI represents an efficient method to solve the high oocyte degeneration rate; the optimal ICSI timing and the best polar body position during the injection have not been clarified; injected zona-free oocytes, if handled carefully, can develop up to blastocyst stage and implant; efficient options can be offered to patients who suffered fertilization failure in previous conventional ICSI cycles. Most controversial and inconclusive are data on the best method to select a viable spermatozoa when only immotile spermatozoa are available for ICSI and, to date, there is no reliable approach to completely filter out spermatozoa with fragmented DNA from an ejaculate. However, most of the studies do not report essential clinical outcomes, such as live birth, miscarriage and fetal abnormality rate, which are essential to establish the safety of a procedure. Conclusions: This review provides the current knowledge on some controversial technical aspects of the ICSI procedures in order to improve its efficacy in specific contexts. Notwithstanding that embryologists might benefit from the approaches presented herein in order to improve ICSI outcomes, this area of expertise still demands a greater number of well-designed studies, especially in order to solve open issues about the safety of these procedures

    New organotin(IV) complexes with L-Arginine,Nα-t-Boc-L-Arginine and L-Alanyl-L-Arginine.Synthesis, structural investigations and cytotoxic activity

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    Novel diorganotin(IV) derivatives of L-Arginine (HArg), Nα-(tert-Butoxycarbonyl)-L-Arginine (Boc-Arg-OH) and L-Ala-L-Arg (H2Ala-Arg), H2NC(=NH)NH(CH2)3CH(NHR)CO2H, where R = H in HArg, R = C(O)OC(CH3)3 in Boc-Arg-OH, R = H2NCH(CH3)CO in H2Ala-Arg and triorganotin(IV) derivatives of Boc-Arg-OH have been synthesized and structurally characterized. The complexes were investigated by FT-IR and 119Sn Mössbauer in the solid state and by 1H, 13C, 119Sn and 1H-1H COSY NMR spectroscopy, in solution. The spectroscopic characterization leading to the proposed molecular structures was accomplished on the basis of these experiments. L-Arginine appears to behave as a chelating ligand through carboxylate and -NH2 groups in Me2Sn(Arg)2, while in N-t-Boc-L-Arginine complex, the N-protected amino group being exempted from coordination, only the carboxylate groups are effectors of bonding to the organometallic moieties. FT-IR spectra give a clear indication that guanidino groups in all the complexes are not involved in coordination, since (C=N-H) frequency of the terminal guanidino group is fairly constant and unshifted relative to the free ligand. The biological activity of organotin(IV)-complexes was also investigated by use of human HT29 colorectal carcinoma cells. The cytotoxic activity of the compounds was determined by the MTT quantitative colorimetric assay, capable of detecting viable cells in comparison with that exerted by cisplatin. A marked cytotoxic activity for nearly all complexes, is evident being higher than that exerted by cisplatin, while no significant improvement of activity was observed for Me2Sn(Arg)2 and Me2Sn(Ala-Arg), which was confirmed by IC50 values. Then, we assessed whether the cytotoxicity induced by organotin(IV) complexes was associated with the induction of apoptosis. Light microscopy analysis, performed to study the morphological changes induced in HT29 cells, confirmed the results obtained with MTT test. No significant morphological alterations were observed in HT29 cells after treatment with Me2Sn(Ala-Arg) and Me2Sn(L-Arg)2. Cells treated with nBu2Sn(Boc-Arg)2, nBu2Sn(Ala-Arg), nBu3Sn(Boc-Arg) and Me3Sn(Boc-Arg), appeared rounded, isolated and detached from culture substrate, indicating the commitment to apoptotic cell death

    Negative regulation of beta enolase gene transcription in embryonic muscle is dependent upon a zinc finger factor that binds to the G-rich box within the muscle-specific enhancer.

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    We have previously identified a muscle-specific enhancer within the first intron of the human beta enolase gene. Present in this enhancer are an A/T-rich box that binds MEF-2 protein(s) and a G-rich box (AGTGGGGGAGGGGGCTGCG) that interacts with ubiquitously expressed factors. Both elements are required for tissue-specific expression of the gene in skeletal muscle cells. Here, we report the identification and characterization of a Kruppel-like zinc finger protein, termed beta enolase repressor factor 1, that binds in a sequence-specific manner to the G-rich box and functions as a repressor of the beta enolase gene transcription in transient transfection assays. Using fusion polypeptides of beta enolase repressor factor 1 and the yeast GAL4 DNA-binding domain, we have identified an amino-terminal region responsible for the transcriptional repression activity, whereas a carboxyl-terminal region was shown to contain a potential transcriptional activation domain. The expression of this protein decreases in developing skeletal muscles, correlating with lack of binding activity in nuclear extract from adult skeletal tissue, in which novel binding activities have been detected. These results suggest that in addition to the identified factor, which functionally acts as a negative regulator and is enriched in embryonic muscle, the G-rich box binds other factors, presumably exerting a positive control on transcription. The interplay between factors that repress or activate transcription may constitute a developmentally regulated mechanism that modulates beta enolase gene expression in skeletal muscle

    RIP-Chip analysis supports different roles for AGO2 and GW182 proteins in recruiting and processing microRNA targets

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    MicroRNAs (miRNAs) are small non-coding RNA molecules mediating the translational repression and degradation of target mRNAs in the cell. Mature miRNAs are used as a template by the RNA-induced silencing complex (RISC) to recognize the complementary mRNAs to be regulated. To discern further RISC functions, we analyzed the activities of two RISC proteins, AGO2 and GW182, in the MCF-7 human breast cancer cell lin

    Addressing the Role of Angiogenesis in Patients with Advanced Pancreatic Neuroendocrine Tumors Treated with Everolimus: A Biological Prospective Analysis of Soluble Biomarkers and Clinical Outcomes

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    Simple Summary Despite the approval of new targeted therapies for pancreatic neuroendocrine tumors (PanNETs) over the past decades, the early identification of resistant tumors remains the major challenge, mainly because clear signs of tumor shrinkage are rarely achieved by imaging assessment. Starting from the hypothesis that angiogenesis can be implicated in the resistance to mTOR inhibitors, we evaluated a specific angiogenesis panel (through the measurement of soluble biomarkers for angiogenesis turnover, circulating endothelial cells, and circulating progenitors) as possible predictors of resistance to everolimus or everolimus efficacy in PanNETs. Our study showed that none of the investigated categories of biomarkers had a predictive value for everolimus resistance or efficacy. However, we suggest that circulating endothelial progenitors might be surrogate biomarkers for angiogenesis activity in PanNETs during everolimus treatment, and their baseline levels might correlate with survival outcomes. These data have never been reported before for NETs. Background: The success of targeted therapies in the treatment of pancreatic neuroendocrine tumors has emphasized the strategy of targeting angiogenesis and the PI3K/AKT/mTOR pathway. However, the major challenge in the targeted era remains the early identification of resistant tumors especially when the efficacy is rarely associated to a clear tumor shrinkage at by imaging assessment. Methods: In this prospective study (NCT02305810) we investigated the predictive and prognostic role of soluble biomarkers of angiogenesis turnover (VEGF, bFGF, VEGFR2, TSP-1) circulating endothelial cells and progenitors, in 43 patients with metastatic panNET receiving everolimus. Results: Among all tested biomarkers, we found a specific subpopulation of circulating cells, CD31+CD140b-, with a significantly increased tumor progression hazard for values less or equal to the first quartile. Conclusion: Our study suggested the evidence that circulating cells might be surrogate biomarkers of angiogenesis activity in patients treated with everolimus and their baseline levels can be correlated with survival. However, further studies are now needed to validate the role of these cells as surrogate markers for the selection of patients to be candidates for antiangiogenic treatments

    influenza monitoring in sardinia italy identifies h3 subtype in mediterranean wild migratory birds

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    Introduction: Wild migratory birds are global distributors of pathogens. Sardinia, Italy, is the second largest Island in the Mediterranean and is a land bridge between Europe and Africa. Methodology: We designed a surveillance protocol to investigate wild migratory birds for presence, frequency, and type of avian influenza viruses. We collected over 4,000 avian samples and compared three sampling methods, fecal, cloacal, and tracheal, to determine the most productive for virus identification. To determine frequency of infection, RNA was extracted and RT-PCRs for avian influenza virus genes were run. Positive samples were cultivated for live virus, sub typed and sequenced. Results: Forty-four samples were positive for influenza nucleoprotein gene. We identified two previously unidentified H3 subtype strains and found cloacae to have the highest rate of virus identification and fecal sampling to provide quality RNA and repeatable results for determination of virus presence. Conclusion: Our investigation provides information on the frequency of Mediterranean avian influenza viruses, and validates the initiation of an avian influenza surveillance protocol. Taken together with global avian influenza findings, these results give insight into infectious disease distributions which is important for viral pandemic monitoring and design of preventative measures

    Phylogeography and genomic epidemiology of SARS-CoV-2 in Italy and Europe with newly characterized Italian genomes between February-June 2020

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    Frontotemporal dementia and its subtypes: a genome-wide association study

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    SummaryBackground Frontotemporal dementia (FTD) is a complex disorder characterised by a broad range of clinical manifestations, differential pathological signatures, and genetic variability. Mutations in three genes—MAPT, GRN, and C9orf72—have been associated with FTD. We sought to identify novel genetic risk loci associated with the disorder. Methods We did a two-stage genome-wide association study on clinical FTD, analysing samples from 3526 patients with {FTD} and 9402 healthy controls. To reduce genetic heterogeneity, all participants were of European ancestry. In the discovery phase (samples from 2154 patients with {FTD} and 4308 controls), we did separate association analyses for each {FTD} subtype (behavioural variant FTD, semantic dementia, progressive non-fluent aphasia, and {FTD} overlapping with motor neuron disease FTD-MND), followed by a meta-analysis of the entire dataset. We carried forward replication of the novel suggestive loci in an independent sample series (samples from 1372 patients and 5094 controls) and then did joint phase and brain expression and methylation quantitative trait loci analyses for the associated (p<5 × 10−8) single-nucleotide polymorphisms. Findings We identified novel associations exceeding the genome-wide significance threshold (p<5 × 10−8). Combined (joint) analyses of discovery and replication phases showed genome-wide significant association at 6p21.3, \{HLA\} locus (immune system), for rs9268877 (p=1·05 × 10−8; odds ratio=1·204 95% \{CI\} 1·11–1·30), rs9268856 (p=5·51 × 10−9; 0·809 0·76–0·86) and rs1980493 (p value=1·57 × 10−8, 0·775 0·69–0·86) in the entire cohort. We also identified a potential novel locus at 11q14, encompassing RAB38/CTSC (the transcripts of which are related to lysosomal biology), for the behavioural \{FTD\} subtype for which joint analyses showed suggestive association for rs302668 (p=2·44 × 10−7; 0·814 0·71–0·92). Analysis of expression and methylation quantitative trait loci data suggested that these loci might affect expression and methylation in cis. Interpretation Our findings suggest that immune system processes (link to 6p21.3) and possibly lysosomal and autophagy pathways (link to 11q14) are potentially involved in FTD. Our findings need to be replicated to better define the association of the newly identified loci with disease and to shed light on the pathomechanisms contributing to FTD. Funding The National Institute of Neurological Disorders and Stroke and National Institute on Aging, the Wellcome/MRC Centre on Parkinson's disease, Alzheimer's Research UK, and Texas Tech University Health Sciences Center
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