127 research outputs found

    Evaluation of air contamination in orthopaedic operating theatres in hospitals in Southern Italy: The IMPACT project

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    Postoperative infections are a concern, especially in total knee and total hip arthroplasty. We evaluated the air quality in orthopaedic operating theatres in southeastern Italy to determine the level of bacterial contamination as a risk factor for postoperative infection. Thirty-five hospitals with operating theatres focused on total knee and total hip arthroplasty participated. We sampled the air passively and actively before surgeries began for the day (at rest) and 15 min after the surgical incision (in operation). We evaluated bacterial counts, particle size, mixed vs turbulent airflow systems, the number of doors, number of door openings during procedures and number of people in the operating theatre. We found no bacterial contamination at rest for all sampling methods, and significantly different contamination levels at rest vs in operation. We found no association between the number of people in the surgical team and bacteria counts for both mixed and turbulent airflow systems, and low bacterial loads, even when doors were always open. Overall, the air quality sampling method and type of ventilation system did not affect air quality

    Novel regulators of human gonadal development

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    The production of viable germ cells during human embryonic development determines adult reproductive success. This is particularly true for females, as development of germ cells (GCs) into primordial follicles before birth is imperative for future fertility. During fetal development GCs migrate to the genital ridge to form the gonad, after which several tightly regulated events, including proliferation, differentiation, and association with somatic cells, must occur to form a functional gonad. In the ovary these processes also include the initiation and subsequent arrest of meiosis. These developmental processes are orchestrated by local autocrine and paracrine factors, many of which remain to be identified in the human. In order to decipher further the pathways by which the gonad and GCs develop, potential regulators including prostaglandin (PG) E2, the interleukin (IL)6-type cytokines, and the prokinetecins (PROKs), were examined in the human fetal ovary and PROKs in the human fetal testis. Patterns of gene expression, protein localisation, function, and interaction of the potential mediators throughout human development (8-20 weeks gestation) were determined. Primary fetal tissue was investigated, in addition to immortalized GCs (T-Cam2 cells) and a murine model of fetal ovarian development. PGE2 interacts with known regulators of GC development in non-reproductive organs. It was postulated PGE2 may regulate GC progression by modulating these factors. Examination of PGE2 receptors and precursor enzymes in the fetal ovary revealed that all were present and some were developmentally regulated, with mRNA expression increasing with gestation. These developmentally regulated components were localised to the GCs. The PGE2 receptors were among those differentially expressed, with one localised solely to mature GCs. Culture of human fetal ovary confirmed that PGE2 regulates known regulators of GC development, increasing expression of survival and anti-apoptotic factors. To test the hypothesis that PGE2 is necessary for female GC development, paracetamol, an inhibitor of PGE2 precursor enzymes, was utilised in a murine model of fetal exposure. Fetal ovaries from this experiment displayed disruption of normal development. The IL6-type cytokines are also postulated to be involved in early gonad development, and are known to regulate proliferation and differentiation of mouse embryonic stem and GCs in vitro. A significant increase in transcript levels of the shared receptor components was determined in second trimester human ovaries, as well as developmental increases of several of the IL6-type ligands. Both common receptor components were located specifically in the GCs identifying them as the target of IL6 action in the human fetal ovary. The PROKs regulate cell migration, proliferation and differentiation, and modulate secretion of PGE2 and expression of some IL6-type cytokines. To-date, PROKs have not been examined in the human fetal gonad. Transcript levels were higher in the fetal testis compared to the ovary, with receptor and ligand components increasing with gestation. Most components also increased with gestation in the ovary. However, location of PROK components was strikingly different between the two tissues, with GCs being the primary target of PROK action in the fetal ovary, and Leydig and interstitial cells being the target in the testis. PROKs interaction with other regulators of gonad development was examined utilising a GC line in the case of the ovary and primary interstitial cell cultures in the case of the testis. These studies have identified new factors involved in human fetal gonad development, and how they interact with known regulatory pathways of development

    Selective autophagy degrades DICER and AGO2 and regulates miRNA activity.

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    MicroRNAs (miRNAs) form a class of short RNAs (∼ 21 nucleotides) that post-transcriptionally regulate partially complementary messenger RNAs. Each miRNA may target tens to hundreds of transcripts to control key biological processes. Although the biochemical reactions underpinning miRNA biogenesis and activity are relatively well defined and the importance of their homeostasis is increasingly evident, the processes underlying regulation of the miRNA pathway in vivo are still largely elusive. Autophagy, a degradative process in which cytoplasmic material is targeted into double-membrane vacuoles, is recognized to critically contribute to cellular homeostasis. Here, we show that the miRNA-processing enzyme, DICER (also known as DICER1), and the main miRNA effector, AGO2 (also known as eukaryotic translation initiation factor 2C, 2 (EIF2C2)), are targeted for degradation as miRNA-free entities by the selective autophagy receptor NDP52 (also known as calcium binding and coiled-coil domain 2 (CALCOCO2)). Autophagy establishes a checkpoint required for continued loading of miRNA into AGO2; accordingly, NDP52 and autophagy are required for homeostasis and activity of the tested miRNAs. Autophagy also engages post-transcriptional regulation of the DICER mRNA, underscoring the importance of fine-tuned regulation of the miRNA pathway. These findings have implications for human diseases linked to misregulated autophagy, DICER- and miRNA-levels, including cancer

    Cloning and comparative mapping of a human chromosome 4-specific alpha satellite DNA sequence

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    We have isolated and characterized two human alphoid DNA clones: p4n1/4 and pZ4.1. Clone p4n1/4 identifies specifically the centromeric region of chromosome 4; pZ4.1 recognizes a subset of alphoid DNA shared by chromosomes 4 and 9. The specificity was determined using fluorescence in situ hybridization experiments on metaphase spreads and Southern blotting analysis of human-hamster somatic cell hybrids. The genomic organization of both subsets was also investigated. Comparative mapping on chimpanzee and gorilla chromosomes was performed. p4n1/4 hybridizes to chimpanzee chromosomes 11 and 13, homologs of human chromosomes 9 and 2q, respectively. On gorilla metaphase spreads, p4n1/4 hybridizes exclusively to the centromeric region of chromosome 19, partially homologous to human chromosome 17. No hybridization signal was detected on chromosome 3 of both chimpanzee and gorilla, in both species homolog of human chromosome 4. Identical comparative mapping results were obtained using pZ4.1 probe, although the latter recognizes an alphoid subset distinct from the one recognized by p4n1/4. The implications of these results in the evolution of centromeric regions of primate chromosomes are discussed

    Indizi di colloquio.

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    Estrazione, di G. Montesarchio (pp. 9-10) Presupposti 1. Colloqiando narrazioni, di C. Venuleo (13-64) 2. Costruendo narrazioni, di R. Grassi (pp. 65-93) 3. Formando narrazioni, di E. Marzella (pp. 94-120) Speculazioni 4. La chiamata a colloquio della città, di G. Montesarchio, C. Venuleo, M. Laiso (pp. 123-142) 5. Analisi dei processi collusivi all'interno di un'organizzazione internazionale, di G. Montesarchio, R. Grassi, L. Ruggiero (pp. 143-163) 6. Il resoconto come capacità di pensare le dimensioni culturali del processo formativo, di G. Montesarchio, E. Marzella, I. Costanzo (pp. 164-188
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