142 research outputs found

    Primi studi sull'interazione tra stato di micorrizazione e danni da incendio in una pineta siciliana

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    Nell’ambito di uno studio sulle simbiosi micorriziche delle conifere in ambienti siciliani, è stata avviata un’indagine preliminare sulla interazione tra danni da incendio e stato di micorrizazione in un rimboschimento artificiale di Pinus halepensis Mill. In particolare, nel bosco di Casaboli (Monreale, PA) estesamente interessato da incendi dolosi nell’estate 2017, sono state delimitate tre aree contigue di circa 700 m2, comprendenti una ventina di piante coetanee (30-40 anni) e con differente entità di danno: 1) vegetazione apparentemente sana (S); danni di media entità (M); danni ingenti (I). In ogni area, dopo aver condotto opportuni rilievi dendrometrici, sono stati individuati 5 punti per il prelievo di carote di suolo a due profondità (5-15; 20-30 cm); i campionamenti sono stati ripetuti tre volte nel biennio 2018-19 (giugno e novembre 2018, maggio 2019) e saranno completati a novembre 2019. I frammenti radicali di P. halepensis, recuperati sotto un leggero flusso d’acqua corrente, sono stati osservati allo stereo microscopio, valutando l’Indice di Micorrizazione (IM = n° totale di apici micorrizici/cm di radice) e rilevando, sul numero totale di apici micorrizici, la percentuale di quelli attivi e non (necrotici). Sebbene l’indagine sia ancora in corso, i primi risultati sembrerebbero evidenziare valori di IM maggiori nell’area S, decrescenti in funzione del livello di deperimento. Nel contempo, nel profilo di suolo compreso tra 20 e 30 cm sono stati rilevati i maggiori livelli di micorrizazione, che rimane sensibile anche nelle aree più danneggiate. Ulteriori dati acquisiti nel corso dell’attività di ricerca potranno fornire utili indicazioni per la definizione degli effetti di tale fattore di disturbo nell’ecosistema oggetto di studio

    Kidney derived apolipoprotein M and its role in acute kidney injury

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    Aim: Apolipoprotein M (apoM) is mainly expressed in liver and in proximal tubular epithelial cells in the kidney. In plasma, apoM associates with HDL particles via a retained signal peptide and carries sphingosine-1-phosphate (S1P), a small bioactive lipid. ApoM is undetectable in urine from healthy individuals but lack of megalin receptors in proximal tubuli cells induces loss of apoM into the urine. Besides this, very little is known about kidney-derived apoM. The aim of this study was to address the role of apoM in kidney biology and in acute kidney injury.Methods: A novel kidney-specific human apoM transgenic mouse model (RPTEC-hapoMTG) was generated and subjected to either cisplatin or ischemia/reperfusion injury. Further, a stable transfection of HK-2 cells overexpressing human apoM (HK-2-hapoMTG) was developed to study the pattern of apoM secretion in proximal tubuli cells.Results: Human apoM was present in plasma from RPTEC-hapoMTG mice (mean 0.18 μM), with a significant increase in plasma S1P levels. In vitro apoM was secreted to both the apical (urine) and basolateral (blood) compartment from proximal tubular epithelial cells. However, no differences in kidney injury score was seen between RPTEC-hapoMTG and wild type (WT) mice upon kidney injury. Further, gene expression of inflammatory markers (i.e., IL6, MCP-1) was similar upon ischemia/reperfusion injury.Conclusion: Our study suggests that kidney-derived apoM is secreted to plasma, supporting a role for apoM in sequestering molecules from excretion in urine. However, overexpression of human apoM in the kidney did not protect against acute kidney injury

    Chemotherapy effects on brain glucose metabolism at rest

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    Background: A growing number of studies reports that chemotherapy may impair brain functions inducing cognitive changes which can persist in a subset of cancer survivors. Aims: To investigate the neural basis of the chemotherapy-induced neurobehavioral changes by means of metabolic imaging and voxel-based statistical parametric mapping analyses. Methods: We studied the resting brain [18]FDG-PET/CT images of 43 adult cancer patients with solid (n=12, 28%) or hematologic malignancies (n=31, 72%); 12 patients were studied prior to chemotherapy (No chemotherapy) while treated patients were divided into two matched subgroups: Early High (6 chemotherapy cycles, n=10), and Late Low (>9 months after chemotherapy, <6 chemotherapy cycles, n=21). Findings: Compared to No chemotherapy, the Early High subgroup showed a significant bilateral (p<0.05) lower regional cerebral metabolic rate of glucose metabolism in both the prefrontal cortices and white matter, cerebellum, posterior medial cortices and limbic regions. A similar pattern emerged in the Early High versus Low Late comparison, while no significant result was obtained in the Low Late versus No chemotherapy comparison. The number of cycles and the post-chemotherapy time were negatively and positively correlated, respectively, with a set of these same brain regions. Interpretation: The present study shows that chemotherapy induces significant transient changes in the glucose metabolism of multiple cerebral cortical and white matter regions with a prevailing involvement of the prefrontal cortex. The severity of these changes are significantly related with the number of chemotherapy cycles and a subset of brain regions seems to present longer lasting, but more subtle, metabolic changes

    Dihydroceramide desaturase functions as an inducer and rectifier of apoptosis : effect of retinol derivatives, antioxidants and phenolic compounds

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    Dihydroceramide desaturase (Degs1) catalyses the introduction of 4,5-trans double bond into dihydroceramide to form ceramide. We show here that Degs1 is polyubiquitinated in response to retinol derivatives, phenolic compounds or anti-oxidants in HEK293T cells. The functional predominance of native versus polyubiquitinated forms of Degs1 appears to govern cytotoxicity. Therefore, 4-HPR or celecoxib appear to stimulate the de novo ceramide pathway (with the exception of C24:0 ceramide), using native Degs1, and thereby promote PARP cleavage and LC3B-I/II processing (autophagy/apoptosis). The ubiquitin-proteasomal degradation of Degs1 is positively linked to cell survival via XBP-1s and results in a concomitant increase in dihydroceramides and a decrease in C24:0 ceramide levels. However, in the case of 4-HPR or celecoxib, the native form of Degs1 functionally predominates, such that the apoptotic programme is sustained. In contrast, 4-HPA or AM404 do not produce apoptotic ceramide, using native Degs1, but do promote a rectifier function to induce ubiquitin-proteasomal degradation of Degs1 and are not cytotoxic. Therefore, Degs1 appears to function both as an ‘inducer’ and ‘rectifier’ of apoptosis in response to chemical cellular stress, the dynamic balance for which is dependent on the nature of chemical stress, thereby determining cytotoxicity. The de novo synthesis of ceramide or the ubiquitin-proteasomal degradation of Degs1 in response to anti-oxidants, retinol derivatives and phenolic compounds appear to involve sensors, and for rectifier function, this might be Degs1 itself

    Indagini preliminari sull’attività di degradazione di basidiomiceti cariogeni su legno di castagno

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    Recentemente, presso il Dip. SAAF e in collaborazione con l‘Instituto di Ciencia Animal (ICA) di Cuba, sono state avviati studi rivolti alla valutazione dell’attività celluloso-ligninolitica da parte microrganismi isolati da diverse matrici naturali. Alcuni primi risultati hanno consentito di rilevare la produzione di enzimi litici (cellulasi, laccasi, ecc.) in diversi funghi in collezione. Nell’ambito di questa ricerca, 5 colonie fungine appartenenti a quattro differenti specie di basidiomiceti cariogeni (Armillaria mellea (Val) P. Kumm, Fistulina hepatica (Shaeffer) Withering, due Ganoderma resinaceum Boud e Laetiporus sulphureus (Bull.) Murrill) sono state saggiate su campioni di legno di castagno (rondelle e segatura) provenienti da due siti siciliani (Ficuzza, Palermo e Nebrodi, Messina) e uno toscano (Sammommè, Pistoia). In particolare sono state valutate: 1) la velocità di colonizzazione di ciascun isolato fungino su rondelle delle matrici legnose dei tre siti; 2) la produzione di CO2 conseguente all’attività litica sulle matrici; 3) la risposta quali-quantitativa di ciascuna colonia fungina alla siringaldazina, un azo-composto organico reattivo alle laccasi e perossidasi, enzimi chiave nella degradazione della lignina. I risultati preliminari indicano sia una differente attività litica, a parità di matrice, dei microrganismi studiati, sia una diversa risposta delle matrici, in relazione alla provenienza, a parità di specie fungina. Ulteriori indagini saranno rivolte allo studio del corredo enzimatico dei funghi saggiati e alla caratterizzazione chimico-fisica delle differenti accessioni di castagno, allo scopo di individuare i maggiori determinanti nel processo degradativo del legno

    Terminology of bioanalytical methods (IUPAC Recommendations 2018)

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    Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced

    Terminology of bioanalytical methods (IUPAC Recommendations 2018)

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    free accessRecommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.Peer reviewe
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