Identificazione di frammenti di albumina in sieri normali e di pazienti con insufficienza renale cronica

Una delle funzioni principali dei reni è la funzione emuntoria, cioè la depurazione del sangue dai cataboliti azotati e da un gran numero di altre sostanze dannose. In presenza di malattie renali questa funzione può diminuire fino a scomparire del tutto con il progredire dell’Insufficienza Renale Cronica (IRC) sino alla sindrome uremica conclamata. In questo caso si rende necessaria una terapia sostitutiva della funzione renale, più spesso la dialisi. È noto da tempo che nel plasma sono presenti quantità molto limitate sia di complessi polimerici che di frammenti di albumina. Nelle urine di pazienti con differenti malattie renali sono stati trovati frammenti di albumina. Pertanto è possibile ipotizzare che la concentrazione nel siero di eventuali frammenti di albumina possa aumentare a causa della progressiva riduzione della funzione renale. Scopo di questa tesi è valutare la natura delle proteine presenti nel plasma, ed in particolare dell’albumina, di pazienti uremici, in trattamenti emodialitico, con funzione renale assente. Sono stati esaminati campioni di siero di tre pazienti in trattamento emodialitico cronico e per confronto il siero di un soggetto sano. Per verificare il pattern proteico, in particolare nel range delle proteine con PM minore di 25 kDa, i campioni di siero sono stati sottoposti ad analisi proteomica. I risultati ottenuti confermano che nel siero dei pazienti si ha una maggior espressione, rispetto al controllo, e la formazione di nuovi frammenti nel range di 20-10 kDa. La presenza di frammenti di albumina nel siero viene spiegata dalla letteratura come l’effetto di microvariazioni conformazionali seguenti all’interazione con vari ligandi (acidi grassi, farmaci, ormoni) ed in particolare all’azione antiossidante che coinvolge la Cys-34 dell’albumina. Dato che la riduzione drastica della funzione renale provoca un aumento dello stress ossidativo, è possibile ipotizzare una più facile frammentazione dell’albumina. Per di più i frammenti a basso PM vengono eliminati in misura minore, o nulla, in conseguenza dell’assente funzione renale. Date le numerose funzioni biologiche dell’albumina, è possibile che le alterazioni della sua struttura rilevate nei soggetti uremici, possano concorrere alla patogenesi del complesso quadro clinico della sindrome uremica, da cui sono affetti i pazienti con riduzione notevole della funzione renale. La scoperta e la caratterizzazione di frammenti di questa proteina nei pazienti con insufficienza renale potrebbe inoltre costituire un utile test diagnostico

Marcatori urinari del Danno Renale Acuto: un ruolo anche per le HSP

Riassunto: Il danno renale acuto, Acute Kidney Injury (AKI), è un disturbo molto frequente in pazienti ospedalizzati. Consiste in un danno a livello dei tubuli renali che comporta una rapida diminuzione delle funzioni renali. Negli anni sono state adottate diversi tipi di criteri per la sua classificazione: criterio RIFLE nel 2004, criterio AKIN nel 2007 e infine il criterio KDIGO nel 2011 definito da un gruppo di esperti a livello mondiale. I marcatori utilizzati per la diagnosi possono essere sia plasmatici che urinari: i marcatori plasmatici più tradizionali sono la creatininemia e l’azotemia (BUN), mentre quelli di più recente scoperta comprendono, tra gli altri, NGAL, e cistatina-C; i marcatori urinari sono stato molto rivalutati perché possono dare immediatamente informazioni sullo stato di salute del rene e comprendono NGAL, L-FABP, cistatina-C, KIM-1, IL-18 e alcuni enzimi propri delle cellule tubulari renali. Infine le Heat Shock Proteins (Hsp) sono proteine normalmente presenti in basse quantità nelle cellule ma fortemente upregolate da stress di varia natura, compresi i meccanismi adottati normalmente dalle cellule tubulari per fronteggiare il danno acuto. Tra le varie Hsp upregolate in queste condizioni c’è la Hsp72. In un recente studio questa proteina è stata trovata nelle urine di ratto con AKI da Ishemia/riperfusione. Questo ci fa pensare che possa essere usata come marcatore dello stato di salute del tubulo o come indicatore della gravità del danno anche in casi umani. Abstract: Acute Kidney Injury (AKI) is a frequent disease that affects many hospitalized patients. It consists in a tubular renal damage that turn into a fast decrease of renal function. During years there have been several definitions: RIFLE criteria in 2004, AKIN criteria in 2007 and finally KDIGO criteria in 2011 defined by a worldwide experts group. Biomarkers utilized in the diagnosis of this injury can be detected both in plasma and in urine: traditional plasmatic biomarkers are serum creatinine and azotaemia, while others of recent development are proteins like NGAL and cystatin C; urinary biomarkers have been found to be very helpful in the definition of the renal pathological conditions and they are proteins like NGAL, L-FABP, cystatin-C, KIM-1, IL-18 and some renal tubule cells typical enzymes. Finally Heat Shock Proteins (Hsp) are proteins normally present in cells at very low levels but highly upregulated following different kinds of stress, included normal mechanisms adopted by tubular cells to avoid acute damage. Among these upregulated Hsp, there is Hsp72. in a recent publication it was easily found in the urine of a murin model of AKI from ischemia/reperfusion. This lead us to think that urinary Hsp72 level could serve as an early biomarker to detect, monitor and/or stratify AKI

Nature vs. Culture: present-day spatial distribution and preservation of open-air rock art in the Côa and Douro River Valleys (Portugal)

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Descriptive Norms and Prototypes Predict COVID-19 Prevention Cognitions and Behaviors in the United States: Applying the Prototype Willingness Model to Pandemic Mitigation

Background Early in the COVID-19 pandemic, prevention behavior adoption occurred in a rapidly changing context. In contrast to expectancy-value theories, the Prototype Willingness Model (PWM) is well-suited for investigating novel and socially informed behaviors. Purpose We explored whether PWM social cognitions predicted coronavirus prevention behaviors. Method A representative sample of United States adults (N = 738; Mage = 46.8; 51.8% women; 78% white; April 2020) who had not had COVID-19 reported PWM predictor variables (perceived vulnerability, prevention descriptive norms, prototypes engaging in prevention behavior, and prevention behavioral intentions). Two weeks later, participants reported their prevention behaviors (handwashing, mask-wearing, social distancing, etc.) and future public health behavioral willingness (contact tracing, temperature checks, etc.). Results Controlling for putative demographic, past behavior, and coronavirus-contextual (e.g., local infection rates) covariates, mediation models indicated that higher norms and favorable prototypes were associated with greater prevention behavioral intentions, which in turn predicted increased prevention behavior, F(18, 705) = 92.20, p \u3c .001, R2 = .70. Higher norms and favorable prototypes associated both directly and indirectly (through greater prevention behavioral intention) with greater willingness to engage in emerging public health behaviors, F(15, 715) = 21.49, p \u3c .001, R2 = .31. Conclusions Greater descriptive norms and favorable prototypes for prevention behavior predicted: (a) future prevention behaviors through increases in behavioral intentions and (b) willingness to participate in emerging public health behaviors. These results held across demographic groups, political affiliation, and severity of regional outbreaks. Public health efforts to curb pandemics should highlight normative prevention participation and enhance positive prototypes

Extracellular vesicles in the urine: markers and mediators of tissue damage and regeneration

As in several body fluids, urine is a rich reservoir of extracellular vesicles (EVs) directly originating from cells facing the urinary lumen, including differentiated tubular cells, progenitor cells and infiltrating inflammatory cells. Several markers of glomerular and tubular damage, such as WT-1, ATF3 and NGAL, as well as of renal regeneration, such as CD133, have been identified representing an incredible source of information for diagnostic purposes. In addition, urinary extracellular vesicles (uEVs) appear to be involved in the cell-to-cell communication along the nephron, although this aspect needs further elucidation. Finally, uEVs emerge as potential amplifying or limiting factors in renal damage. Vesicles from injured cells may favour fibrosis and disease progression whereas those from cells with regenerative potential appear to promote cell survival. Here, we will discuss the most recent findings of the literature, on the light of the role of EVs in diagnosis and therapy for damage and repair of the renal tissue

First historical records of Carcharhinus brachyurus (Chondrichthyes, Carcharhiniformes) in the Mediterranean Sea

The dried jaws of two specimens of Carcharhinus brachyurus were found in the collections of the Zoological Museum of the University of Palermo. Both pieces belong to the great Doderlein collection of fishes from Sicily assembled during the end of the nineteenth century (1862-1892) and are labelled as Carcarias (Prionodon) lamia and Carcharias lamia, respectively. These findings represent the first historical evidence of the presence of C. brachyurus in the Mediterranean Sea and add the southern Tyrrhenian to the species distribution within the Mediterranean. Moreover, sexual dimorphism in tooth morphology is documented for the first time in Mediterranean specimens. Some meristic and morphological data concerning the dentition are given, and a critical analysis of the presence of the species in the Mediterranean is presented. © 2009 Unione Zoologica Italiana

The interplay between cognitive and affective risks in predicting COVID-19 precautions: a longitudinal representative study of Americans

Objective Cognitive risk figures prominently in models predicting health behaviors, but affective risk is also important. We examined the interplay between cognitive risk (personal likelihood of COVID-19 infection or death) and affective risk (worry about COVID-19) in predicting COVID-19 precautionary behaviors. We also examined how outbreak severity bias (overestimation of the severity of COVID-19 in one’s community) predicted these outcomes. Design In a representative sample of U.S. adults (N = 738; Mage = 46.8; 52% women; 78% white), participants who had not had COVID-19 took two online surveys two weeks apart in April 2020. Main outcome measures We assessed cognitive risk, affective risk, and outbreak severity bias at baseline and at follow-up two precaution variables: prevention behaviors (e.g. social distancing) and behavioral willingness (e.g. vaccinations). Results Overall, affective risk better predicted precautions than cognitive risk. Moreover, overestimating the severity of the outbreak predicted more affective risk (but not cognitive risk) and in turn more precautions. Additional analyses showed that when affective risk was lower (as opposed to higher) greater cognitive risk and outbreak severity bias both predicted more precautions. Conclusion These findings illustrate the importance of affective risk and outbreak severity bias in understanding COVID-19 precautionary behavior

Analyse morphométrique et caractérisation des sols des dolines dans le district de Gorazbon de la Forêt expérimentale de Kheyrud-Kenar (nord de l’Iran)

A doline is a natural superficial enclosed depression of karst landscapes, usually circular or subcircular in plan and with a few to a hundred meters in diameter. This very distinctive and common karst landform can appear in a variety of shapes and sizes. The spatial distribution, description and evolution of dolines were investigated in the Gorazbon district of Kheyrud-Kenar Experimental Forest (northern Iran). Morphometric measurements and systematic collection of soil cover samples were performed for each observed doline during field survey. Morphometric parameters such as doline’s length, width, side slopes and perimeter were measured. Afterward, the area, depth, circularity index, length/width ratio and length/depth ratio were also calculated and used for the quantification of the individual dolines. Two other parameters were instead used to infer the degree of karstification of the study area: i.e., the spatial density of dolines and the pitting index. The laboratory determination of physical (color, texture) and chemical (pH, CaCO3, organic matter) soil properties were conducted on the collected samples. The obtained results indicate the presence of mainly solution dolines in the study area with an irregular spatial distribution, as well as a general high degree of karstification. The studied dolines show the axes of length and width with a certain asymmetry, resulting in a shape from sub-circular to elliptical. Soil characterization point out to the hypothesis of a possible incipient develop of subcutaneous shallow holes (pipes - not yet visible on surface) at the dolines bottoms, probably linked to the underground karst system (enlarged fissures and/or even caves). Doline’s longer axes seem aligned with to the major regional structural geological elements. All these data could indicate the presence of an early stage in the origin of collapse dolines, with obvious implications in terms of natural hazards. In this context, we believe that a proper decision-making in forest management, and in specific environmental planning policies, should always consider this karst quantitative information (and approach) on the mutual relationship between the forest stand development and the natural landforms that characterize the study area.Une doline est une dépression superficielle fermée dans des paysages karstiques, généralement circulaire ou subcirculaire et avec une dimension jusqu'à des centaines de mètres de diamètre. Cette forme du relief karstique, très distinctif et commun, peut apparaître dans une variété de formes et de tailles. La distribution spatiale, la description morphologique et l'évolution des dolines ont été étudiées dans le district de Gorazbon de la Forêt expérimentale de Kheyrud-Kenar (nord de l'Iran). Des mesures morphométriques et une collecte systématique d'échantillons de couverture du sol ont été effectuées pour chaque doline observée au cours du travail sur le terrain. Les paramètres morphométriques tels que la longueur, la largeur, les pentes latérales et le périmètre de la doline ont été mesurés. Ensuite, l'aire, la profondeur, l'indice de circularité, le rapport longueur/largeur et le rapport longueur/profondeur ont été calculés et utilisés pour la caractérisation morphométrique de chacune des dolines. Par la suite, deux autres paramètres ont été utilisés pour déduire le degré de karstification de la zone de la zone étudiée: la densité spatiale des dolines en nombre et la densité spatiale des dolines en aire occupée). La détermination en laboratoire des propriétés physiques (couleur, texture) et chimiques (pH, CaCO3, matière organique) du sol a été effectuée sur les échantillons prélevés. Les résultats obtenus indiquent la présence de dolines principalement dans la zone d'étude avec une distribution spatiale irrégulière, ainsi qu'un degré général élevé de karstification. Les dolines étudiées montrent les axes de longueur et de largeur avec une certaine asymétrie, résultant en une forme de sub-circulaire à elliptique. La caractérisation des sols rappelle l'hypothèse d'un éventuel début de développement de cavités peu profondes, pas encore visibles en surface, au fond des dolines, probablement liées au système karstique souterrain (des fissures élargies et/ou même des grottes). Les axes plus longs des dolines semblent alignés sur les principaux éléments géologiques structurels au niveau régional. Toutes ces données pourraient indiquer la présence d'un stade précoce dans l'origine des dolines d'effondrement, avec des implications évidentes en termes de risques naturels. Dans ce contexte, nous pensons qu'une prise de décision appropriée en matière de gestion forestière et dans des politiques spécifiques de planification environnementale devrait toujours tenir compte de ces informations quantitatives karstiques (et de cette approche) sur la relation mutuelle entre le développement des peuplements forestiers et les reliefs naturels qui caractérisent cette zone d'étude.info:eu-repo/semantics/publishedVersio

GEOCHEMICAL EXPRESSION OF SPELEOTHEME GROWTH FROM XRFAND LA-ICP-MS: PALEOCLIMATIC IMPLICATIONS

Carbonate cave deposits have a widespread use in deciphering climatic signals from the past using several proxies (e.g. stable isotope compositions). In the western central part of Portugal, the Mesozoic sediments of the Lusitanian basin are particularly susceptible to dissolve by interaction with meteoric waters and to develop karstic caves, especially in the Lower and Middle Jurassic limestone and dolomitic limestone formations. A set of the existing caves from Sicó and Estremadura Carbonate Massifs (e.g. Soprador do Carvalho, Buraca Grande and Ourão Caves, as well as Vale do Pena and Algar do Pena Caves) were detailed study and several speleothem samples (stalagmites and flowstones) were collected aiming to contribute to the deciphering of the climatic evolution of this region. The selected cave stalagmite was collected in the main epiphreatic conduct of the Soprador do Carvalho Cave (an underground system located on the eastern border of the Sicó Massif) and was studied by handheld X-ray fluorescence to determine the major elements trends and by LA-ICP-MS for the analysis of the minor and trace-elements. The cave floor is covered by siliciclastic fine (clayey/sandy) and clast-supported conglomerate sediments carried into the cave from the adjacent areas by floodwater. As expected, the chemical composition of the speleothem is dominated by the presence of calcium with all samples presenting counts of the same magnitude for this element, although the older portion of the stalagmite has slightly lower counts than the rest of it. Iron is another remarkable element that present a subtle tendency to be more concentrated in the outer (younger) layers. With LA-ICP-MS several transects were made on the thin sections covering layers of distinct optical characteristics. The older layers, which exhibit a more hyaline aspect, have higher counts of elements such as sodium, uranium and lead and lower counts on rare-earth elements and yttrium. More, the analysed elements oscillate between high counts and low counts from layer to layer along the entire sample. The oscillatory character of the trace-element distribution in the stalagmite can be interpreted as the result of the seasonal variations of meteoric water input, and time of residence on the hanging-wall formations, with periods of more efficient dissolution of the percolating water alternating with periods of less efficiency. The more general evolution observed in the composition of older and younger sectors of the speleothem can be interpreted as being the evidence for a probable change in the paleoclimate conditions of the area and perhaps can be used to detect underground flood events during the Quaternary

Palaeolithic engravings and sedimentary environments in the Côa River Valley (Portugal): implications for the detection, interpretation and dating of open-air rock art

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