Confronto tra Inquiry-based Science Education ed insegnamento tradizionale delle Scienze in alcune scuole superiori italiane

This study aims to evaluate if inquiry-based science education (IBSE) at the high school level allows the achievement of better learning objectives with respect to conventional science education (CSE). The findings would help to understand if, how, and why IBSE can be used as a successful teaching approach. The study included four high schools with different specialties, eight experienced science teachers and approximately 350 students, attending sixteen classes. Two biochemistry topics were taught by the same teacher in two classes. A two stage quasi experimental, crossover design was adopted. The primary outcome compared the difference in the average pre-teaching and post-teaching test-scores, using a 3-multilevel analysis. On average, the outcome in terms of scores significantly improved by 4% with IBSE with respect to the CSE approach, demonstrating differences among the school specialties. In conclusion, our study indicates that IBSE is significantly more effective in enhancing skills.Questo studio mira a valutare se l’approccio “Inquiry-based science education” (IBSE) consenta il raggiungimento di obiettivi di apprendimento, a livello di scuola superiore, in modo più efficacerispetto all’educazione scientifica convenzionale (CSE). I risultati possono aiutare a capire se, come e perché IBSE può essere utilizzato come approccio didattico di successo. Lo studio ha inclusoquattro scuole superiori con diversi indirizzi, otto insegnanti di scienze con esperienza e circa 350 studenti, suddivisi in sedici classi. Due tematiche di biochimica sono state insegnate dallo stesso docente in due classi parallele. È stato adottato un disegno quasi sperimentale, crossover, a due fasi. Obiettivo primario è stato confrontare la differenza nei punteggi medi nei test prima e dopo le attività, utilizzando un’analisi gerarchica a 3 livelli. In media, il risultato in termini di punteggi è migliorato significativamente del 4% con IBSE rispetto all’approccio CSE, dimostrando differenze tra gli indirizzi scolastici. In conclusione, il nostro studio indica che IBSE è significativamente più efficace nel migliorare le competenze

Participation of the 39-kDa glycoprotein (gp39) of the vitelline envelope of Bufo arenarum eggs in sperm-egg interaction

The acquisition of egg fertilizability in Bufo arenarum takes place during the oviductal transit and during this process the extracellular coelomic envelope (CE) of the eggs is converted into the vitelline envelope (VE). It has been stated that one of the necessary events leading to a fertilizable state is the proteolytic cleavage of CE glycoproteins in the oviductal pars recta by oviductin, a serine protease. Consequently, there is a marked increase in the relative quantity of glycoproteins with 39 (gp39) and 42-kDa (gp42) in the VE. In the present study, sperm-VE binding assays using heat-solubilized biotin-conjugated VE glycoproteins revealed that both gp39 and gp42 have sperm binding capacity. According to this result, our study was focused on gp39, a glycoprotein that we have previously reported as a homologue of mammalian ZPC. For this purpose, rabbit polyclonal antibodies against gp39 were generated at our laboratory. The specificity of the antibodies was confirmed with Western blot of VE glycoproteins separated on SDS-PAGE. Immunohistochemical and immunoelectron studies showed gp39 distributed throughout the width of the VE. In addition, immunofluorescence assays probed that gp39 bound to the sperm head. Finally, as an approach to elucidate the possible involvement of gp39 in fertilization, inhibition assays showed that pretreatment of eggs with antibodies against gp39 generated a significant decrease in the fertilization rate. Therefore, our findings suggest that gp39, which is modified by oviductal action, participates as a VE glycoprotein ligand for sperm in Bufo arenarum fertilization.Fil: Barrera, Antonio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Llanos, Ricardo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Miceli, Dora Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin

An In-Silico Comparative Study of Lipases from the Antarctic Psychrophilic Ciliate Euplotes focardii and the Mesophilic Congeneric Species Euplotes crassus: Insight into Molecular Cold-Adaptation

Cold-adapted enzymes produced by psychrophilic organisms have elevated catalytic activities at low temperatures compared to their mesophilic counterparts. This is largely due to amino acids changes in the protein sequence that often confer increased molecular flexibility in the cold. Comparison of structural changes between psychrophilic and mesophilic enzymes often reveal molecular cold adaptation. In the present study, we performed an in-silico comparative analysis of 104 hydrolytic enzymes belonging to the family of lipases from two evolutionary close marine ciliate species: The Antarctic psychrophilic Euplotes focardii and the mesophilic Euplotes crassus. By applying bioinformatics approaches, we compared amino acid composition and predicted secondary and tertiary structures of these lipases to extract relevant information relative to cold adaptation. Our results not only confirm the importance of several previous recognized amino acid substitutions for cold adaptation, as the preference for small amino acid, but also identify some new factors correlated with the secondary structure possibly responsible for enhanced enzyme activity at low temperatures. This study emphasizes the subtle sequence and structural modifications that may help to transform mesophilic into psychrophilic enzymes for industrial applications by protein engineering

EMBO/EMBL Symposium

Ciliates (Alveolata, Ciliophora possess a diverse association of symbiotic bacteria. They can be present as endosymbionts or localized in the outer surface as ectosymbionts. In a previous study we reported the characterization of a bacterial consortium associated to E. focardii, a strict psychrophilic ciliate isolated from the Terra Nova Bay, Antarctica (Pucciarelli et al 2015), This consortium is composed by Bacteroidetes (19%), Alpha proteobacteria (28%), Beta proteobacteria (5%), and Gamma proteobacteria (33%) In the present study, we report the isolation of bacterial strains from this consortium. In particular, we were interested in the isolation of bacterial strains able to growth in the presence of pollutants, in order to verify their potential application in bioremediation. By using culture enrichment technique with different source of pollutants such as diesel oil, methanol and cadmium chloride, we succeeded to isolate three bacterial species. The amplification and sequencing of the 16S rDNA genes revealed that the isolated strains were Marinomonas sp, Rhodococcus sp, and Bacillus sp., respectively. Fluorescence In Situ Hybridization (FISH) technique revealed the intracellular localization of Marinomonas sp, whereas the other two strains are still under investigation. This study opens the way to the discovery of new bacterial strains that can grow under extreme conditions and that can be used in bioremediation. Furthermore, the characterization of the bacterial consortium in E focardii contributes to understand how different organisms cooperate for environmental adaptation

Rational engineering of a cold-adapted α-amylase from the Antarctic ciliate Euplotes focardii for simultaneous improvement of thermostability and catalytic activity

The α-amylases are endo-acting enzyme which hydrolyze starch by randomly cleaving the 1,4-α-D-glucosidic linkages between the adjacent glucose units in linear amylose chain. It has significant advantages in a wide range of applications, in particular in food industry. The eukaryotic α-amylase isolated from the Antarctic ciliated protozoon Euplotes focardii (EfAmy) is an alkaline enzyme, differently from most of the α-amylases characterized so far. Furthermore, EfAmy shows the characteristics of a psychrophilic α-amylase, such as the highest hydrolytic activity at low temperature and high thermolability, which is the major drawback of cold-active enzymes in industrial applications. In this work, we applied site-directed mutagenesis combined with rational design to generate a cold-active EfAmy with improved thermostability and catalytic efficiency at low temperatures. We engineered two EfAmy mutants: in one mutant we introduced Pro residues on the A and B domains in surface loops. In the second mutant we changed Val into Thr residues close to the catalytic site. The aim of these substitutions was to rigidify the molecular structure of the enzyme. Furthermore, we also analyzed mutants containing these combined substitutions. Biochemical enzymatic assays of engineered versions of EfAmy revealed that the combination of mutations at the surface loops increased thermostability and catalytic efficiency of the enzyme. The possible mechanisms responsible for changes in the biochemical properties are discussed by analyzing the three-dimensional structural model.IMPORTANCE Cold-adapted enzymes have high specific activity at low and moderate temperatures, a property that can be extremely useful in various applications as it implies a reduction in energy consumption during the catalyzed reaction. However, the concurrent high thermolability of cold-adapted enzymes often limits their applications in industrial processes. The α-amylase from the psychrophilic Antarctic ciliate Euplotes focardii (named EfAmy) is a cold-adapted enzyme with optimal catalytic activity in alkaline environment. These unique features distinguish it from most α-amylases characterized so far. In this work, we engineered the novel EfAmy with improved thermostability, substrate binding affinity and catalytic efficiency to various extents, without impact on its pH preference. These characteristics can be considered an important property to be used in food, detergents, textiles and other industrial applications. The enzyme engineering strategy developed in this study may also provide useful knowledge for future optimization of molecules to be used in particular industrial applications

UV Radiation and Visible Light Induce hsp70 Gene Expression in the Antarctic Psychrophilic Ciliate Euplotes focardii

The psychrophilic ciliate Euplotes focardii inhabits the shallow marine coastal sediments of Antarctica, where, over millions of years of evolution, it has reached a strict molecular adaptation to such a constant-temperature environment (about −2 °C). This long evolution at sub-zero temperatures has made E. focardii unable to respond to heat stress with the activation of its heat shock protein (hsp) 70 genes. These genes can, however, be expressed in response to other stresses, like the oxidative one, thus indicating that the molecular adaptation has exclusively altered the heat stress signaling pathways, while it has preserved hsp70 gene activation in response to other environmental stressors. Since radiative stress has proved to be affine to oxidative stress in several organisms, we investigated the capability of UV radiation to induce hsp70 transcription. E. focardii cell cultures were exposed to several different irradiation regimes, ranging from visible only to a mixture of visible, UV-A and UV-B. The irradiation values of each spectral band have been set to be comparable with those recorded in a typical Antarctic spring. Using Northern blot analysis, we measured the expression level of hsp70 immediately after irradiation (0-h-labeled samples), 1 h, and 2 h from the end of the irradiation. Surprisingly, our results showed that besides UV radiation, the visible light was also able to induce hsp70 expression in E. focardii. Moreover, spectrophotometric measurements have revealed no detectable endogenous pigments in E. focardii, making it difficult to propose a possible explanation for the visible light induction of its hsp70 genes. Further research is needed to conclusively clarify this point. Antonietta La Terza and Roberto Marangoni are joint last authors

Psychosocial Findings in Alcohol-Dependent Patients Before and After Three Months of Total Alcohol Abstinence

Alcohol use disorders (AUDs) may be associated with several psychological and affective disorders. It is controversial, however, if these symptoms are a cause or rather a consequence of alcohol dependence. There are few data testing simultaneously psychosocial and affective disorders before and after a period of alcohol abstinence. The aim of this study was to perform multiple psychometric evaluations in alcohol-dependent patients before and after 12 weeks of abstinence. Twenty-five alcohol-dependent patients were included in the study. The following psychometric tests were administered at baseline (T0) and after 12 weeks (T1): addiction severity index (ASI), brief psychiatric rating scale (BPRS), social behavior scale (SBS), Sheehan disability scale (DISS), aggression questionnaire (AQ). At T1, 16 (64%) patients were abstinent, 5 (20%) patients dropped out and 4 (16%) patients relapsed. Compared to T0, patients totally abstinent at T1 showed a significant reduction of the scores related to BPRS, BPRS-E and its subscales (except BPRS 5), ASI 1, ASI 2, ASI 3, ASI 6, ASI 7, BSM, AQ, DISS 1, DISS 2, DISS 3 (p < 0.05). No significant changes in ASI 4, ASI 5, DISS 4, and DISS 5, BPRS 5 scores were found at T1 compared to T0. The present study indicates that total alcohol abstinence improves psychometric features, such as alcohol addiction severity, psychiatric rating, social behavior, aggressiveness, and disability. Larger controlled studies are needed to confirm these findings

Characterization of the first eukaryotic cold-adapted patatin-like phospholipase from the psychrophilic Euplotes focardii: Identification of putative determinants of thermal-adaptation by comparison with the homologous protein from the mesophilic Euplotes crassus

The ciliated protozoon Euplotes focardii, originally isolated from the coastal seawaters of Terra Nova Bay in Antarctica, shows a strictly psychrophilic phenotype, including optimal survival and multiplication rates at 4e5 C. This characteristic makes E. focardii an ideal model species for identifying the molecular bases of cold adaptation in psychrophilic organisms, as well as a suitable source of novel cold-active enzymes for industrial applications. In the current study, we characterized the patatin-like phospholipase from E. focardii (EfPLP), and its enzymatic activity was compared to that of the homologous protein from the mesophilic congeneric species Euplotes crassus (EcPLP). Both EfPLP and EcPLP have consensus motifs conserved in other patatin-like phospholipases. By analyzing both esterase and phospholipase A2 activity, we determined the thermostability and the optimal pH, temperature dependence and substrates of these enzymes. We demonstrated that EfPLP shows the characteristics of a psychrophilic phospholipase. Furthermore, we analyzed the enzymatic activity of three engineered versions of the EfPLP, in which unique residues of EfPLP, Gly80, Ala201 and Val204, were substituted through site-directed mutagenesis with residues found in the E. crassus homolog (Glu, Pro and Ile, respectively). Additionally, three corresponding mutants of EcPLP were also generated and characterized. These analyses showed that the substitution of amino acids with rigid and bulky charged/hydrophobic side chain in the psychrophilic EfPLP confers enzymatic properties similar to those of the mesophilic patatin-like phospholipase, and vice versa. This is the first report on the isolation and characterization of a cold-adapted patatin-like phospholipase from eukaryotes. The results reported in this paper support the idea that enzyme thermaladaptation is based mainly on some amino acid residues that influence the structural flexibility of polypeptides and that EfPLP is an attractive biocatalyst for industrial processes at low temperatures

Potential Application of Lung Ultrasound in Children with Severe Uncontrolled Asthma: Preliminary Hypothesis Based on a Case Series

: In recent years, lung ultrasound (LUS) has been increasingly used for the diagnosis of respiratory diseases in both adult and pediatric patients. However, asthma is a field in which the use of LUS is not yet well defined, or is in development. In the following case series, we describe clinical, laboratory, and radiological results, as well as detailed lung ultrasound findings of six children with asthma: some of them with acute asthma attack and with inadequately controlled allergic asthma or childhood asthma; others with acute asthma and allergic or infantile asthma adequately controlled by preventive therapy. Finally, we describe the clinical, laboratory, and imaging parameters of a child with severe allergic asthma in the absence of exacerbation. In these cases, albeit at different times, LUS played an important role in both the initial diagnostic process and follow-up. It also showed different ultrasound features depending on the severity of the individual asthma based on the type of asthmatic phenotype and control of it

Distinct Functional Roles of beta-Tubulin Isotypes inMicrotubule Arrays of Tetrahymena thermophila, aModel Single-Celled Organism

Background The multi-tubulin hypothesis proposes that each tubulin isotype performs a unique role, or subset of roles, in the universe of microtubule function(s). To test this hypothesis, we are investigating the functions of the recently discovered, noncanonical β-like tubulins (BLTs) of the ciliate, Tetrahymena thermophila. Tetrahymena forms 17 distinct microtubular structures whose assembly had been thought to be based on single α- and β-isotypes. However, completion of the macronuclear genome sequence of Tetrahymena demonstrated that this ciliate possessed a β-tubulin multigene family: two synonymous genes (BTU1 and BTU2) encode the canonical β-tubulin, BTU2, and six genes (BLT1-6) yield five divergent β-tubulin isotypes. In this report, we examine the structural features and functions of two of the BLTs (BLT1 and BLT4) and compare them to those of BTU2. Methodology/Principal Findings With respect to BTU2, BLT1 and BLT4 had multiple sequence substitutions in their GTP-binding sites, in their interaction surfaces, and in their microtubule-targeting motifs, which together suggest that they have specialized functions. To assess the roles of these tubulins in vivo, we transformed Tetrahymena with expression vectors that direct the synthesis of GFP-tagged versions of the isotypes. We show that GFP-BLT1 and GFP-BLT4 were not detectable in somatic cilia and basal bodies, whereas GFP-BTU2 strongly labeled these structures. During cell division, GFP-BLT1 and GFP-BLT4, but not GFP-BTU2, were incorporated into the microtubule arrays of the macronucleus and into the mitotic apparatus of the micronucleus. GFP-BLT1 also participated in formation of the microtubules of the meiotic apparatus of the micronucleus during conjugation. Partitioning of the isotypes between nuclear and ciliary microtubules was confirmed biochemically. Conclusion/Significance We conclude that Tetrahymena uses a family of distinct β-tubulin isotypes to construct subsets of functionally different microtubules, a result that provides strong support for the multi-tubulin hypothesis