In VitroReconstitution of the Recombinant Photosystem II Light-harvesting Complex CP24 and Its Spectroscopic Characterization

The light-harvesting chlorophyll a/b protein CP24, a minor subunit of the photosystem II antenna system, is a major violaxanthin-binding protein involved in the regulation of excited state concentration of chlorophyll a. This subunit is poorly characterized due to the difficulty in isolation and instability during purification procedures. We have used an alternative approach in order to gain information on the properties of this protein; the Lhcb6 cDNA has been overexpressed in bacteria in order to obtain the CP24 apoprotein, which was then reconstituted in vitro with xanthophylls, chlorophyll a, and chlorophyll b, yielding a pigment-protein complex with properties essentially identical to the native protein extracted from maize thylakoids. Although all carotenoids were supplied during refolding, the recombinant holoprotein exhibited high selectivity in xanthophyll binding by coordinating violaxanthin and lutein but not neoxanthin or beta-carotene. Each monomer bound a total of 10 chlorophyll a plus chlorophyll b and two xanthophyll molecules. Moreover, the protein could be refolded in the presence of different chlorophyll a to chlorophyll b ratios for yielding a family of recombinant proteins with different chlorophyll a/b ratios but still binding the same total number of porphyrins. A peculiar feature of CP24 was its refolding capability in the absence of lutein, contrary to the case of other homologous proteins, thus showing higher plasticity in xanthophyll binding. These characteristics of CP24 are discussed with respect to its role in binding zeaxanthin in high light stress conditions. The spectroscopic analysis of a recombinant CP24 complex binding eight chlorophyll b molecules and a single chlorophyll a molecule by Gaussian deconvolution allowed the identification of four subbands peaking at wavelengths of 638, 645, 653, and 659 nm, which have an increased amplitude with respect to the native complex and therefore identify the chlorophyll b absorption in the antenna protein environment. Gaussian subbands at wavelengths 666, 673, 679, and 686 nm are depleted in the high chlorophyll b complex, thus suggesting they derive from chlorophyll a

Geomorphology of Naples and the Campi Flegrei: human and natural landscapes in a restless land

Naples and its surroundings are a very young landscape, originated from 40 ka in response to strong and explosive volcanic processes, which created the Campi Flegrei, one of the largest volcanic fields of the world. Despite the repeated and continuous volcanic activity, this territory was selected for human settlements since Neolithic times and hosted some of the most important Greek and Roman towns in the Mediterranean area (e.g., Cuma, Parthenope, Neapolis, Baia and Puteoli). Geoarcheological data and historical chronicles testify to human coexistence with eruptions, bradyseismic ground motions, coastline changes, floods and landslides. With the aim of describing the geomorphological evolution of this area to a wide audience, including also non-experts, we constructed a synthetic geomorphological map of the area and sketches that synthesise the main stages of the geomorphological evolution of the historical centre of Naples and the coastal belt of the Gulf of Pozzuoli during the last millennia

Urinary Metabolic Profile of Patients with Transfusion-Dependent β-Thalassemia Major Undergoing Deferasirox Therapy

Introduction: Renal dysfunction is a frequent complication in patients suffering from β-thalassemia major (β-TM). The aim of this study was to analyze the renal function and urine metabolomic profile of β-TM patients undergoing transfusions and deferasirox (DFX) therapy, in order to better characterize and shed light on the pathogenesis of renal disease in this setting. Methods and Subjects: 40 patients affected by β-TM treated with DFX and 35 age- and gender-matched healthy controls were enrolled in the study. Renal function was assessed. Glomerular filtration rate (GFR) was estimated with CKD-EPI and Schwartz formula for adults and children, respectively. Renal tubular function and maximal urine concentration ability were tested. Urine specimens were analyzed by nuclear magnetic resonance spectroscopy to identify the urinary metabolite profiles. Results: The study of renal function in β-TM patients revealed normal estimated (e)GFR mean values and the albumin-to-creatinine ratio was <30 mg/g. The analysis of tubular function showed normal basal plasma electrolyte levels; 60% of patients presented hypercalciuria and many subjects showed defective urine concentration. Several amino acids, N-methyl compounds, and organic acids were overexcreted in the urine of thalassemic patients compared with controls. Discussion: The major finding of this work is that β-TM patients and controls exhibit different concentrations of some metabolites in the urine. Early recognition of urinary abnormalities may be useful to detect and prevent kidney damage

Sex- and age-related differences in the management and outcomes of chronic heart failure: an analysis of patients from the ESC HFA EORP Heart Failure Long-Term Registry

Aims: This study aimed to assess age- and sex-related differences in management and 1-year risk for all-cause mortality and hospitalization in chronic heart failure (HF) patients. Methods and results: Of 16 354 patients included in the European Society of Cardiology Heart Failure Long-Term Registry, 9428 chronic HF patients were analysed [median age: 66 years; 28.5% women; mean left ventricular ejection fraction (LVEF) 37%]. Rates of use of guideline-directed medical therapy (GDMT) were high (angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, beta-blockers and mineralocorticoid receptor antagonists: 85.7%, 88.7% and 58.8%, respectively). Crude GDMT utilization rates were lower in women than in men (all differences: P\ua0 64 0.001), and GDMT use became lower with ageing in both sexes, at baseline and at 1-year follow-up. Sex was not an independent predictor of GDMT prescription; however, age >75 years was a significant predictor of GDMT underutilization. Rates of all-cause mortality were lower in women than in men (7.1% vs. 8.7%; P\ua0=\ua00.015), as were rates of all-cause hospitalization (21.9% vs. 27.3%; P\ua075 years. Conclusions: There was a decline in GDMT use with advanced age in both sexes. Sex was not an independent predictor of GDMT or adverse outcomes. However, age >75 years independently predicted lower GDMT use and higher all-cause mortality in patients with LVEF 6445%

Organizzazione e lavori del Congresso

Il congresso People/environment relationships from the Mesolithic to the Middle Ages: recent geo-archaeological findings in Southern Italy è stato organizzato per iniziativa di alcuni membri del Dipartimento di Scienze della Terra dell’Università “Federico II” di Napoli (A. Cinque, P. Romano e E. Russo Ermolli), in collaborazione con le Soprintendenze Archeologiche della Campania (rappresentate dai Soprintendenti P. Guzzo, M. L. Nava e G. Tocco) col patrocinio del Ministero per i Beni e le At..

Effetti catastrofici distali della eruzione del Vesuvio nel 79 d.C.: evidenze sedimentarie e geo-archeologiche in Penisola Sorrentina

I Monti Lattari (una dorsale carbonatica a circa 20Km a sud del cratere del Vesuvio) hanno registrato la deposizione di una copertura piroclastica spessa da 1 a 2.5m in occasione dell’eruzione pliniana del 79 d.C. Come dimostrano i molti lembi residui di depositi vulcanoclastici (Durece), i depositi di caduta della suddetta eruzione sono stati soggetti a rapidi processi di erosione che hanno determinato (1) l’aggradazione decametrica di stretti fondivalle, (2) la riattivazione di conoidi alluvionali e (3) la crescita di corpi sedimentari deltizi. Questa risposta è stata primariamente dovuta alle pendenze mediamente elevate dell’area di studio e all’elevata erodibilità del materiale piroclastico. Molti dati geoarcheologici indicano che la risedimentazione dei prodotti piroclastici sia avvenuta nell’arco di tempo di alcune decadi, ed è stata seguita da una rapida fase di erosione. Questa nota sottolinea la necessità di considerare la possibile reazione catastrofica dei sistemi naturali alle eruzioni esplosive anche in aree non vulcaniche ubicate ad una certa distanza dai centri eruttivi.Les Monti Lattari (horst carbonaté à 20 km au sud du Vésuve) a enregistré le dépôt d’une couverture pyroclastique d’un à 2,5 m d’épaisseur lors de l’éruption de 79 AD. Ces dépôts ont été rapidement érodés et ont induit (1) l’aggradation décamétrique des fonds de vallée, (2) La réactivation des cônes de déjection alluviale et (3) la progradation des deltas. Ces impacts sont prioritairement liés aux pentes importantes des versants et à l’érodibilité élevée des dépôts d’origine volcanique. De nombreuses données géoarchéologiques montrent que la re-sédimentation des dépôts pyroclastiques est rapide et suivie d’une phase d’érosion. Notre étude montre qu’en périphérie non volcanique, les impacts des éruptions peuvent être catastrophiques.During the 79 A.D. Plinian eruption, the Lattari Mountains (a carbonate ridge located 20 km south of Vesuvius) were covered by a pyroclastic layer, 1 to 2.5 m in thickness. As demonstrated by widespread remants of the volcanoclastic Durece deposits, rapid erosional processes driven by steep slopes subsequently reworked the soft and loose pyroclastic material leading to (1) tens of metres of valley filling, (2) alluvial fan growth, and (3) fan delta formation. Several archaeostratigraphic records scattered in the study area demonstrate that the reworking and deposition of the pyroclastic deposits occurred over many decades and was followed by a phase of incision. The data collected underline the importance of carrying out careful investigations on the catastrophic impacts of explosive eruptions in areas located several kilometres from volcanoes