Thermal behaviour of a heterothermic enzyme: A4 lactate dehydrogenase from Triturus cristatus

The behaviour of T. cristatus A₄ lactate dehydrogenase at different temperatures was studied on the pure isoenzyme. The molecule displays a number of properties which do not conform to any current model of biochemical adaptation to temperature. Our hypothesis is that the structure of newt LDH evolved is such a way to become able to sustain its physiological action over the entire thermal range of the species, and thus no adjustment in kinetic features is needed when temperature varies.     

Evidences of olive pollination date variations in relation to spring temperature trends

Airborne pollen concentration patterns reflect flowering phenology of a given species, and it may be a sensitive regional indicator in climate change studies. This paper presents the relationship between a strategic biological event, such as olive flowering, and the air temperature trend, registered over a large scale (1982–2007) in the Umbria region. The aim of the study was to determine relationships between phenological behaviour (flowering) of olive trees and the air temperature trend (1982–2007) in the Umbria region. The phenological data on flowering phase were registered indirectly through an aerobiological monitoring technique. The obtained results showed a strong relationship between phenology and thermal trend. This characteristic was confirmed from results of correlations between temperature (mean temperature from 1st March) and flowering dates, especially that of full flowering (r = −0.9297). Moreover, the results showed an advance trend of 6, 8 and 10 days, respectively of start, full and end of flowering dates. The advance of the recorded flowering time in this period is to ascribe mainly to the increase of mean temperature and above all to that registered in months of May and June.     

Role of alpha-fetoprotein in selection of patients with hepatocellular carcinoma waiting for liver transplantation: must we reconsider it?

Background: Milan criteria (MC) represent the most commonly adopted criteria for the selection of patients with hepatocellular carcinoma (HCC) waiting for liver transplantation (LT). However, MC are exclusively based on morphological aspects. The aim of the present study was to evaluate pre-LT-detectable biological parameters, to compare them with morphological ones in terms of tumor recurrence prediction and patient survival. Methods: A cohort of 153 consecutive adult patients who underwent LT for HCC on cirrhosis from January 1999 to March 2009 was retrospectively analyzed. Results: HCC recurrence was observed in 12 patients (7.8%). At multivariate logistic regression analysis, serum alpha-fetoprotein (AFP) was the unique independent negative risk factor for the development of HCC recurrence (odds ratio 2.0, p=0.03). Adopting a cutoff value of 210 ng/mL, patients who presented serum AFP =210 ng/mL showed a 5-year survival rate of 23.3% versus 76.2% observed in patients with pre-LT serum AFP <210 ng/mL (log-rank test: <0.0001). Conclusions: In our experience, AFP was the strongest predictor of HCC recurrence, stronger than tumor morphology. AFP could ameliorate the selection of LT candidates. Further studies to evaluate the combination of morphological and biological criteria are needed.     

Sulla validità del genere Torulaspora

Zusammenfassung An 20 Stämmen von Torulaspora Rosei und 1 Stamm von Zygosaccharomyces globiformis forma typica wurde insbesondere die Sporenbildung untersucht. Da diese bei jenen immer parthenogenetisch erfolgt, muß die Gattung Torulaspora aufrecht erhalten werden.     

Considerazioni sulla torulopsis pulcherrima

Zusammenfassung Aus Mosten von Umbrien und Toscana wurden 23 zu Torulopsis pulcherrima (Lindner) Saccardo gehörige Stämme isoliert, von denen 21 als die typische Art zu identifizieren waren (Rötung der Kultur nur bei Gegenwart von Eisen), während 2 Stämme, als var. rubra n. var. bezeichnet, sich außer durch andere Eigenschaften auch durch intensivere Farbstoffbildung unterscheiden.