267 research outputs found
Autologous fat grafting after sarcoma surgery : evaluation of oncological safety
Background: The regenerative effectiveness of lipoaspirate procedures relies on the presence of mesenchymal stem cells, but the stromal microenvironment and hormonal secretions of the adipose tissue may be involved in cancer growth. Only few oncological outcome studies of fat grafting at the surgical site of malignant neoplasms of mesenchymal origin are available; none of these studies examined a series of sarcoma cases. Objectives: We analyzed outcome in terms of local or distant spread and overall survival to investigate the oncological safety of fat grafting in patients with sarcoma. Patients and methods: Sixty consecutive patients who had undergone 143 fat grafting procedures after surgical resection of bone and soft tissue sarcomas of the head, trunk, and limbs with clear resection margins were enrolled from 2004 to 2015 in our tertiary care center. A multidisciplinary sarcoma team administered adjuvant therapies. Patients were recurrence free at fat grafting. Results: The overall median follow-up was 7.5 years. At follow-up after fat grafting (2.4 years), one patient had distant metastasis and two had local relapse. Kaplan–Meier analysis showed disease-free survival rate of 95.4% (CI: 89.1–100.0) at 24 months. The risk of local recurrence (LR) within 24 months was 4.6% (CI: 0.0–20.9). The probability of not having LR after fat grafting was ≥ 89.1%. Conclusion: We found no evidence of an increased cancer risk after fat grafting procedures in patients with sarcoma, but a stimulatory role of fat cannot be excluded for bone sarcomas based on the cases reported here, and further studies are therefore needed
Autologous fat grafting after sarcoma surgery : evaluation of oncological safety
Background: The regenerative effectiveness of lipoaspirate procedures relies on the presence of mesenchymal stem cells, but the stromal microenvironment and hormonal secretions of the adipose tissue may be involved in cancer growth. Only few oncological outcome studies of fat grafting at the surgical site of malignant neoplasms of mesenchymal origin are available; none of these studies examined a series of sarcoma cases. Objectives: We analyzed outcome in terms of local or distant spread and overall survival to investigate the oncological safety of fat grafting in patients with sarcoma. Patients and methods: Sixty consecutive patients who had undergone 143 fat grafting procedures after surgical resection of bone and soft tissue sarcomas of the head, trunk, and limbs with clear resection margins were enrolled from 2004 to 2015 in our tertiary care center. A multidisciplinary sarcoma team administered adjuvant therapies. Patients were recurrence free at fat grafting. Results: The overall median follow-up was 7.5 years. At follow-up after fat grafting (2.4 years), one patient had distant metastasis and two had local relapse. Kaplan\u2013Meier analysis showed disease-free survival rate of 95.4% (CI: 89.1\u2013100.0) at 24 months. The risk of local recurrence (LR) within 24 months was 4.6% (CI: 0.0\u201320.9). The probability of not having LR after fat grafting was 65 89.1%. Conclusion: We found no evidence of an increased cancer risk after fat grafting procedures in patients with sarcoma, but a stimulatory role of fat cannot be excluded for bone sarcomas based on the cases reported here, and further studies are therefore needed
Design of Allosteric Stimulators of the Hsp90 ATPase as New Anticancer Leads
Allosteric compounds that stimulate Hsp90 adenosine triphosphatase (ATPase) activity were rationally designed, showing anticancer potencies in the low micromolar to nanomolar range. In parallel, the mode of action of these compounds was clarified and a quantitative model that links the dynamic ligand-protein cross-talk to observed cellular and in vitro activities was developed. The results support the potential of using dynamics-based approaches to develop original mechanism-based cancer therapeutics
Exploring miR-9 Involvement in Ciona intestinalis Neural Development Using Peptide Nucleic Acids
The microRNAs are small RNAs that regulate gene expression at the post-transcriptional level and can be involved in the onset of neurodegenerative diseases and cancer. They are emerging as possible targets for antisense-based therapy, even though the in vivo stability of miRNA analogues is still questioned. We tested the ability of peptide nucleic acids, a novel class of nucleic acid mimics, to downregulate miR-9 in vivo in an invertebrate model organism, the ascidian Ciona intestinalis, by microinjection of antisense molecules in the eggs. It is known that miR-9 is a well-conserved microRNA in bilaterians and we found that it is expressed in epidermal sensory neurons of the tail in the larva of C. intestinalis. Larvae developed from injected eggs showed a reduced differentiation of tail neurons, confirming the possibility to use peptide nucleic acid PNA to downregulate miRNA in a whole organism. By identifying putative targets of miR-9, we discuss the role of this miRNA in the development of the peripheral nervous system of ascidians
Hmx gene conservation identifies the evolutionary origin of vertebrate cranial ganglia
The evolutionary origin of vertebrates included innovations in sensory processing associated with the acquisition of a predatory lifestyle. Vertebrates perceive external stimuli through sensory systems serviced by cranial sensory ganglia (CSG) which develop from cranial placodes; however understanding the evolutionary origin of placodes and CSGs is hampered by the gulf between living lineages and difficulty in assigning homology between cell types and structures. Here we use the Hmx gene family to address this question. We show Hmx is a constitutive component of vertebrate CSG development and that Hmx in the tunicate Ciona is able to drive the differentiation program of Bipolar Tail Neurons (BTNs), cells previously thought neural crest homologs. Using Ciona and lamprey transgenesis we demonstrate that a unique, tandemly duplicated enhancer pair regulated Hmx in the stem-vertebrate lineage. Strikingly, we also show robust vertebrate Hmx enhancer function in Ciona, demonstrating that deep conservation of the upstream regulatory network spans the evolutionary origin of vertebrates. These experiments demonstrate regulatory and functional conservation between Ciona and vertebrate Hmx, and confirm BTNs as CSG homologs. Our analysis also identifies derived evolutionary changes, including a genetic basis for secondary simplicity in Ciona and unique regulatory complexity in vertebrates
Hmx gene conservation identifies the evolutionary origin of vertebrate cranial ganglia
The evolutionary origin of vertebrates included innovations in sensory processing associated with the acquisition of a predatory lifestyle. Vertebrates perceive external stimuli through sensory systems serviced by cranial sensory ganglia (CSG) which develop from cranial placodes; however understanding the evolutionary origin of placodes and CSGs is hampered by the gulf between living lineages and difficulty in assigning homology between cell types and structures. Here we use the Hmx gene family to address this question. We show Hmx is a constitutive component of vertebrate CSG development and that Hmx in the tunicate Ciona is able to drive the differentiation program of Bipolar Tail Neurons (BTNs), cells previously thought neural crest homologs. Using Ciona and lamprey transgenesis we demonstrate that a unique, tandemly duplicated enhancer pair regulated Hmx in the stem-vertebrate lineage. Strikingly, we also show robust vertebrate Hmx enhancer function in Ciona, demonstrating that deep conservation of the upstream regulatory network spans the evolutionary origin of vertebrates. These experiments demonstrate regulatory and functional conservation between Ciona and vertebrate Hmx, and confirm BTNs as CSG homologs. Our analysis also identifies derived evolutionary changes, including a genetic basis for secondary simplicity in Ciona and unique regulatory complexity in vertebrates
Teratogenic potential of nanoencapsulated vitamin A evaluated on an alternative model organism, the tunicate Ciona intestinalis
Nano-encapsulation is a technology used to pack substances in order to enhance their stability and bioavailability, but this packing may interact with living systems, causing unexpected toxicity. Vitamin A (vit A) is a substance that has received attention, because in developed countries, the increasing availability of supplements is leading to its excessive intake. This study aims to compare teratogenic effects caused by exposure to the traditional formulation of vit A versus nano-encapsulated vit A. We used ascidian embryos as an alternative model. Ascidians are marine organisms closely related to vertebrates that share with them a body plan and developmental programme, including the morphogenetic role of retinoic acid (RA). Our data showed that the adverse effects of exposure to the same concentration of the two formulations were different, suggesting that the nano-encapsulation increased the bioavailability of the molecule, which could be better absorbed and metabolised to RA, the effective teratogenic substance
Luminescent conjugates between dinuclear rhenium complexes and 17α-ethynylestradiol: synthesis, photophysical characterization, and cell imaging
Three new luminescent conjugates between dinuclear rhenium complexes and an estradiol, namely E2-Re, are described. The derivatives have the general formula [Re2(\u3bc-Cl)2(CO)6(\u3bc-R-pydz-17\u3b1-ethynylestradiol)] (R-pydz = functionalized 1,2-pyridazine), where the estradiol moiety is covalently bound to the \u3b2 position of the pyridazine ligand. Different synthetic pathways are investigated, including the inverse-type [4 + 2] Diels Alder cycloaddition reaction between the electron poor 1,2,4,5-tetrazine and 17\u3b1-ethynylestradiol for the synthesis of E2-Re1. The three E2-Re conjugates are purified on silica gel and isolated in a spectroscopically pure form in moderate to good yields (28-50%). All the E2-Re conjugates are comprehensively characterized from the spectroscopic and photophysical points of view. Cellular internalization experiments on human MCF-7 and 231 cells are also reported, displaying interesting staining differences depending on the nature of the spacer linking the estradiol unit to the organometallic fragment. Furthermore, the suitability of these conjugates to also stain simple multicellular organisms, i.e. Ciona intestinalis embryos and larvae at different stages of development, is reported here for the first time
Differences between microhabitat and broad-scale patterns of niche evolution in terrestrial salamanders
The extent to which closely related species share similar niches remains highly debated. Ecological niches are increasingly analysed by combining distribution records with broad-scale climatic variables, but interactions between species and their environment often occur at fine scales. The idea that macroscale analyses correctly represent fine-scale processes relies on the assumption that average climatic variables are meaningful predictors of processes determining species persistence, but tests of this hypothesis are scarce. We compared broad- and fine-scale (microhabitat) approaches by analyzing the niches of European plethodontid salamanders. Both the microhabitat and the macroecological approaches identified niche differences among species, but the correspondence between micro- and macroecological niches was weak. When exploring niche evolution, the macroecological approach suggested a close relationship between niche and phylogenetic history, but this relationship did not emerge in fine-scale analyses. The apparent pattern of niche evolution emerging in broad-scale analyses likely was the by-product of related species having closely adjacent ranges. The environment actually experienced by most of animals is more heterogeneous than what is apparent from macro-scale predictors, and a better combination between macroecological and fine-grained data may be a key to obtain robust ecological generalizations
Studio degli effetti miscela sullo sviluppo embrionale in vitro di due composti con diverso meccanismo d’azione (fluconazolo ed etanolo) utilizzando due diversi modelli sperimentali: coltura di embrioni di ratto e esposizione di embrioni di Ascidia
Scopo di questo lavoro \ue8 stato quello di valutare in vitro gli effetti miscela sul potenziale teratogeno della co-esposizione a Fluconazolo (FLUCO, fungicida azolico ampiamente utilizzato in ambito clinico) ed a concentrazioni sub-teratogene di Etanolo (Eth). Nella prima parte di questo studio, embrioni post-impianto di ratto sono stati esposti in vitro a concentrazioni crescenti di FLUCO (62.5-125-250-500\ub5M), alla concentrazione non effetto di Eth (1\ub5L/mL) o sono stati co-esposti a FLUCO 62.5-125-250-500\ub5M ed Eth (1\ub5L/mL). Al termine del periodo di coltura (48 ore) gli embrioni sono stati esaminati morfologicamente e processati per valutare l\u2019espressione dei geni specificamente coinvolti nel metabolismo dell\u2019Acido Retinoico (adh7, cyp26a1, cyp26b1, cyp26c1) o la distribuzione delle loro proteine nell\u2019embrione. Eth da solo non ha indotto effetti avversi sullo sviluppo embrionale. I gruppi esposti a FLUCO 125-250-500\ub5M mostravano specifiche anomalie a livello dell\u2019apparato branchiale, comparabili a quelle precedentemente documentate e correlate ad un probabile aumento di RA. Gli effetti erano dose-dipendenti sia per la frequenza degli embrioni malformati che per la gravit\ue0 delle malformazioni osservate. FLUCO 62.5 \ue8 stata individuata come la NOAEL (No Observed Adverse Effect Level). Gruppi co-esposti a FLUCO ed Eth mostravano un aumento significativo dell\u2019effetto teratogeno rispetto ai gruppi esposti al solo FLUCO. In seguito alla co-esposizione con Eth, FLUCO 62.5 \ub5M mostrava pi\uf9 del 35% degli embrioni anomali. Tale concentrazione non era pi\uf9 identificabile come NOAEL. L\u2019analisi dell\u2019espressione genica ha rivelato che la sola esposizione a Eth o a FLUCO 62.5 \ub5M alterava l\u2019espressione di geni coinvolti nel catabolismo di RA (cyp26a1, cyp26c1) e che tale alterazione peggiorava in seguito alla co-esposizione. La immunocolorazione per CYP26a1 e CYP26c1 non ha evidenziato differenze nelle aree embrionali coinvolte nella loro espressione, che risultavano sovrapponibili nell\u2019area cefalica ai territori di espressione del marker delle cellule delle creste neurali (CRABP1). I dati ottenuti mostrano che la co-esposizione con Eth alla concentrazione sub-teratogena pu\uf2 aumentare il potenziale teratogeno del FLUCO. Questi risultati sono di particolare rilevanza considerando che FLUCO ed Eth non condividono lo stesso meccanismo d\u2019azione: FLUCO interferisce con il catabolismo di RA, mentre Eth potrebbe interferire con la sintesi endogena di RA. L\u2019analisi dell\u2019espressione dei geni correlati al metabolismo di RA suggerisce che l\u2019effetto miscela indotto da FLUCO ed Eth potrebbe essere spiegato da un accumulo di RA dovuto all\u2019azione delle due sostanze.
Nella seconda parte di questo studio, embrioni dell\u2019ascidia Ciona intestinalis (Chordata, Tunicata) sono stati esposti in vitro dallo stadio di neurula allo stadio di larva natante a concentrazioni crescenti di FLUCO (31.5-62.5-125-250-500\ub5M), alla concentrazione non effetto di Eth (1\ub5L/mL) o sono state co-esposte a FLUCO 62.5-125-250-500\ub5M ed Eth (1\ub5L/mL). Al termine del periodo di coltura (15 ore) le larve sono state esaminate morfologicamente. Eth da solo non ha indotto effetti avversi sullo sviluppo embrionale, mentre i gruppi esposti a FLUCO mostravano specifiche anomalie a livello delle strutture anteriori, comparabili a quelle gi\ue0 documentate e correlate all\u2019esposizione a RA. \uc8 stato osservato un significativo aumento di larve con malformazioni gravi nei gruppi co-esposti alle miscele di FLUCO ed Eth. I dati preliminari ottenuti sembrano indicare l\u2019ascidia come un adeguato modello alternativo per lo screening teratogeno delle miscele ottenute da fungicidi azolici: viene confermata l\u2019ipotesi di un ruolo chiave dell\u2019Eth nell\u2019aumentare il potenziale teratogeno del FLUCO, puntando l\u2019attenzione su un possibile impatto ambientale dei fungicidi azolici
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