188 research outputs found

    Vascularization of the human intervertebral disc: A scoping review

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    Intervertebral discs (IVDs) are often referred to as the largest avascular structures of the human body, yet a collective resource characterizing the vascularization of the IVD does not exist. To address this gap, the objective of this study was to conduct a comprehensive search of the literature to review and summarize current knowledge of the prevalence and localization of blood supply in human IVDs, with a scoping review. A comprehensive search of peer-reviewed publications on the topic of IVD vascularization in humans was conducted across six electronic databases: PubMed, EMBASE, MEDLINE, Scopus, Web of Science, and BIOSIS Previews. Studies of humans were included regardless of age, sex, ethnicity, and health status, with the exception of IVD herniation. Two independent reviewers screened titles and abstracts and full-texts according to eligibility criteria. The review was conducted and reported according to Preferred Reporting Items for Systematic Reviews Extension for Scoping Reviews guidelines. Our search yielded 3122 articles, with 22 articles meeting the inclusion criteria. The study samples ranged in age from fetal to \u3e90 years and included both sexes, various health statuses, and used different methodologies (eg, histology, medical imaging, and gross dissection) to assess vasculature. Overall, consistent observations were that (a) the nucleus pulposus of the IVD is avascular throughout life, (b) both the cartilage endplates and annulus fibrosus receive considerable blood supply early in life that diminishes over the lifespan, and (c) vascular ingrowth into the cartilage endplates and inner layers of the annulus fibrosus is commonly associated with damaged or disrupted tissue, irrespective of age. Histology and immunohistochemistry are often used to report vascularization of the IVD. The body of the current literature suggests that the IVD should not be generalized as an avascular tissue. Instead, vascularization of the IVD differs based on the constituent tissues, their age, and state of degeneration or damage

    The Role of Parental Involvement in Youth Sport Experience: Perceived and Desired Behavior by Male Soccer Players

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    Parents play a key role in the youth sports educational experience. They are responsible for the introduction of their children to physical or sporting education and their involvement has been associated with sport participation in early stages. The aims of this cross-sectional study were, first, to assess the perceived and desired parental involvement by children and, secondly, to examine their satisfaction or dissatisfaction with any specific behavior. 80 male soccer players filled the Parental Involvement in Sport Questionnaire (PISQ) before or after a training session in presence of a coach. PISQ results revealed excessive active involvement and pressure, insufficient praise and understanding and satisfactory directive behavior from children’s parents. Our findings suggest that excessive parental involvement can cause pressure on children who would prefer parental participation characterized by praise and understanding. A balance between a supporting involvement without putting too much pressure is needed by the parents. To prevent burnout and dropout and to facilitate future practice, parents should be counseled (possibly by a sport educator) on how to positively support their children concerning their sport experience

    Links between the three-dimensional movements of whale sharks (Rhincodon typus) and the bio-physical environment off a coral reef

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    Funding: This research was supported by funding from Santos Ltd and The Australian Institute of Marine Science (AIMS).Background Measuring coastal-pelagic prey fields at scales relevant to the movements of marine predators is challenging due to the dynamic and ephemeral nature of these environments. Whale sharks (Rhincodon typus) are thought to aggregate in nearshore tropical waters due to seasonally enhanced foraging opportunities. This implies that the three-dimensional movements of these animals may be associated with bio-physical properties that enhance prey availability. To date, few studies have tested this hypothesis. Methods Here, we conducted ship-based acoustic surveys, net tows and water column profiling (salinity, temperature, chlorophyll fluorescence) to determine the volumetric density, distribution and community composition of mesozooplankton (predominantly euphausiids and copepods) and oceanographic properties of the water column in the vicinity of whale sharks that were tracked simultaneously using satellite-linked tags at Ningaloo Reef, Western Australia. Generalised linear mixed effect models were used to explore relationships between the 3-dimensional movement behaviours of tracked sharks and surrounding prey fields at a spatial scale of ~ 1 km. Results We identified prey density as a significant driver of horizontal space use, with sharks occupying areas along the reef edge where densities were highest. These areas were characterised by complex bathymetry such as reef gutters and pinnacles. Temperature and salinity profiles revealed a well-mixed water column above the height of the bathymetry (top 40 m of the water column). Regions of stronger stratification were associated with reef gutters and pinnacles that concentrated prey near the seabed, and entrained productivity at local scales (~ 1 km). We found no quantitative relationship between the depth use of sharks and vertical distributions of horizontally averaged prey density. Whale sharks repeatedly dove to depths where spatially averaged prey concentration was highest but did not extend the time spent at these depth layers. Conclusions Our work reveals previously unrecognized complexity in interactions between whale sharks and their zooplankton prey.Publisher PDFPeer reviewe

    Valutazione dello stato della biodiversità in aree antropizzate: applicazione della metodologia BRUV (Baited Remote Underwater Video) per lo studio della componente nectonica dell'ecosistema

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    Uno studio di valutazione dello stato della biodiversità focalizzato sulla componente nectonica e finalizzato alla determinazione dell’abbondanza e della composizione in specie del popolamento marino costiero si può avvalere di diversi strumenti e metodologie, le quali possono essere più o meno invasive sull’ecosistema oggetto dello studio. È possibile ad esempio applicare delle metodologie di pesca sperimentale, i.e. di prelievo degli organismi dal loro ambiente al fine di riconoscere e quantificare la presenza delle specie nectoniche nell’area di studio. Esistono tuttavia metodologie meno distruttive che permettono la raccolta di dati attraverso una stima visiva dell’abbondanza e della composizione delle specie direttamente nel loro ambiente naturale. Di queste metodologie fanno parte i censimenti visivi in situ (Samoilys M.A. 1997), i quali hanno il vantaggio di permettere la raccolta dati nel rispetto della biodiversità, evitando eventi mortali e/o fortemente stressanti agli individui oggetto dello studio. Questo fa si che tali metodologie risultino particolarmente utili in ambienti vulnerabili e/o soggetti a particolari vincoli protezionistici volti alla conservazione dell’ambiente marino, come le Aree Marine Protette (AMP), le quali in questo studio rappresentano delle zone di confronto caratterizzate da un limitato impatto antropico. Per tali ragioni, nell’ambito del progetto CISAS è stato scelto di portare avanti la valutazione dello stato del popolamento ittico attraverso una particolare tecnica di censimento visivo, la quale viene effettuata attraverso il sistema BRUV (Baited Remote Underwater Video)

    MicroRNAs as Regulators of Neo-Angiogenesis in Hepatocellular Carcinoma

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    Hepatocellular carcinoma (HCC) is a highly vascularized neoplasm. In the tumor niche, abundant angiogenesis is fundamental in providing nutrients for tumor growth and represents the first escape route for metastatic cells. Active angiogenesis, together with metastasis, are responsible for the reduction of recurrence-free survival of HCC. MicroRNAs (miRNAs) are small non-coding RNAs that have recently drawn attention in molecular targeted therapy or as diagnostic and prognostic biomarkers. MiRNA expression in HCC has been widely studied in the last decade. Some miRNAs have been found to be up- or down-regulated, besides association with apoptosis, metastasis progression and drug resistance have been found. This review article aims to summarize the angiogenetic process in tumor diseases and to update on what has been found in the vast world of HCC-related-miRNAs and, eventually, to report the latest finding on several miRNAs involved in HCC angiogenesis. We searched the state of the arts for the 12 miRNAs found to be involved with angiogenesis in HCC (miR-29b, miR-126-3p, miR-144-3p, miR-146a, miR-195, miR-199a-3p, miR-210-3p, miR-338- 3p, mir-491, mir-497, mir-638, mir-1301) and reported their main molecular targets and their overall effect in the sprouting of new vessels

    Inhibition of DNA methylation sensitizes glioblastoma for tumor necrosis factor-related apoptosis-inducing ligand-mediated destruction

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    Life expectancy of patients affected by glioblastoma multiforme is extremely low. The therapeutic use of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been proposed to treat this disease based on its ability to kill glioma cell lines in vitro and in vivo. Here, we show that, differently from glioma cell lines, glioblastoma multiforme tumors were resistant to TRAIL stimulation because they expressed low levels of caspase-8 and high levels of the death receptor inhibitor PED/PEA-15. Inhibition of methyltransferases by decitabine resulted in considerable up-regulation of TRAIL receptor-1 and caspase-8, down-regulation of PED/PEA-15, inhibition of cell growth, and sensitization of primary glioblastoma cells to TRAIL-induced apoptosis. Exogenous caspase-8 expression was the main event able to restore TRAIL sensitivity in primary glioblastoma cells. The antitumor activity of decitabine and TRAIL was confirmed in vivo in a mouse model of glioblastoma multiforme. Evaluation of tumor size, apoptosis, and caspase activation in nude mouse glioblastoma multiforme xenografts showed dramatic synergy of decitabine and TRAIL in the treatment of glioblastoma, whereas the single agents were scarcely effective in terms of reduction of tumor mass, apoptosis induction, and caspase activation. Thus, the combination of TRAIL and demethylating agents may provide a key tool to overcome glioblastoma resistance to therapeutic treatments. ©2005 American Association for Cancer Research

    Monitoraggio delle risorse ittiche e della pesca: indagine sugli spostamenti di specie marine di interesse commerciale e conservazionistico

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    Il monitoraggio degli spostamenti degli organismi marini è un importante strumento per la comprensione della biologia delle specie ma anche per la conservazione e la tutela degli stock intesi come risorsa. Nel caso dell'applicazione su specie che vivono all'interno di Aree Marine Protette, queste tecniche consentono di verificare l'efficacia della protezione. Questo studio riporta l'applicazione di tecniche di telemetria ultrasonica all'aragosta comune (P. elephas) nell'AMP di Isola delle Femmine. Gli individui catturati all'interno dell'AMP ed ivi rilasciati hanno mostrato uno spiccato homing ed un buon livello di fedeltà al sito. Lo studio inoltre è servito a denunciare lo stato attuale di scarsa protezione e suggerisce una riperimetrazione dei confini dell'AMP
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