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Trattamento topico della oftalmomiasi esterna da Oestrus ovis: progettazione e sviluppo di un nuovo preparato galenico
No full textIntroduction
Ophthalmomyiasis is an infection of the eye caused by the larvae of Oestrus ovis, Diptera. Currently, there are no available drugs to treat this condition in humans and mechanical removal of the larvae is the only effective therapy.
Methods
The study was divided into 3 Phases. The first was designed to identify and test “in vitro” new galenic formulation against O. ovis L1 larvae. The second addressed the cytotoxicity of the compounds tested in phase 1 on corneal and conjunctival cells. We assessed the toxicity of different dilutions of Propylene Glycol and then analyzed the combination of Ivermectin with DMSO, Glycol and Glycol + PVP-I. We also tested the 40, 60, 80X dilution of the stock solution. Finally, we tested the compounds in a rat model, in order to assess the in vivo toxicity of the galenic formulations.
Results
Ivermectin 1% solution and the combination of Ivermectin 1% + PVP-I 0.6% were found to be significantly better than propylene glycol alone, in terms of time needed to kill Larvae (p=0.0422). MTT assay confirmed low tissue toxicity. In the mouse model, no toxicity was found.
Conclusion
Our results suggest that Ivermectin 1% and Propylene glycol are both effective against L1 larvae and could be potential candidates for the treatment of ophthalmomyiasis caused by Oestrus ovis
Exploring stem cell fate from adipose tissue: novel approaches to modulate stem cell signatures
Full text linkStem cells (SCs), undifferentiated elements able to acquire specific phenotype upon stimulation, represent an important source for regenerative medicine, restoring function of compromised organs. The purpose of regenerative biology is to identify the cellular
and molecular differences that distinguish normal tissue turnover from scar repair, in order to create an ideal microenvironment suitable for regeneration in damaged adult tissues. Stem cell differentiation is a complex process controlled by signaling pathways and molecular mechanisms, acting to maintain tissue homeostasis. A wide range of natural molecules and compounds, known as nutraceuticals or functional foods, are widely used for their therapeutic or preventive effects. These natural and synthetic molecules exert their action via epigenetic modulations of a specific molecular differentiation program and gene expression of lineage-specific markers. Within this context, unraveling the cellular mechanisms involved in the activation and differentiation of the adipose resident stem cells, could help in identifying innovative and preventive tools to counteract obesity and its related diseases. The aim of this project was to evaluate cell behavior in the presence of conditioned media, drugs or natural molecules, in the attempt to counteract the molecular mechanisms involved in inflammatory-associated adipogenesis. Understanding the molecular mechanisms involved in the decision of this fate could lead to the development of drugs capable of influencing stem cell behavior, for future in vivo clinical applications
Soil remediation of Lebanese contaminated soils using organic sorbents
No full textThe studies on the influence of organic-based sorbents on the mobility of potentially toxic elements (PTE) in contaminated soils have been constantly growing in the last decades. However, given the variety of PTE and pollution status, as well as the diversity of factors governing the fate of PTE in soil, to date it is still hard to foresee the amendment effectiveness in a specific soil environment. The aim of this PhD thesis was therefore to assess the influence of biochar, compost and their combination on the mobility, (phyto)toxicity and bioavailability of several PTE (i.e. Sb, As, Ni, Cr and Zn) present in different polluted soils of Lebanon.
The addition of compost, biochar and their combination generally reduced labile PTE pools (i.e. readily soluble) and increased their residual (non-extractable) fractions. The amendments also changed the C-source utilization potential of the soil microbial community as revealed by the Biolog community level physiological profile. At the same time, soil dehydrogenase, β-glucosidase and urease were significantly enhanced in amended soils while the growth of Capsicum annuum L. and Triticum aestivum L. (in a selected polluted soil) was significantly enhanced and PTE uptake significantly reduced.
Overall, the results obtained indicated that biochar and compost could be useful to stabilise PTE in contaminated soils, to stimulate soil microbial activity and functionality and to improve plant growth
Ambiente, risorse, territorio e spopolamento in aree di montagna: l’Unione dei Comuni Barbagia e la Serra de Sicó
No full textThis study, whose main goal is to describe those ongoing processes of depopulation taking place in inland areas – both rural and mountainous ones – made it possible to observe how human activities characterizes a territory and how variable are those peculiarities (both material and immaterial ones) that lends originality to it.
We decided to conduct this study focusing on two geographic realities that, although they could be considered – from a certain point of view – heterogeneous, share some common features: one of our study target areas is located in Sardinia (i.e. the Unione dei Comuni Barbagia), the other one is located in the Portuguese Região Centro (i.e. the Serra de Sicó).
The main goal of this study is to examine the effects of depopulation on the territory while furthering our understanding of cultural identities and – especially – of the processes of their construction and reconstruction that take place as a consequence of territorial abandonment. At the same time, we will focus our attention on the fact that local development must arise out of territorial needs and inhabitants’ identities
Effect of rearing systems on the production, reproduction and welfare of small ruminants in Lebanon
Full text linkIn Lebanon, small ruminants hold a key role in the economy of marginal regions and contribute to the income of the population involved in pastoral activities. The production does not meet the national growing demand for milk and meat, thus Lebanon depends on importation to satisfy the needs of the population. The aim of the thesis is to identify the principle rearing systems available in Lebanon and to optimize the small ruminant’s production and reproduction according to those systems. The welfare notion will be studied in order to evaluate its impact on animal productivity and to aware farmers of welfare importance in their management strategy.
The experimental work started by the elaboration of a detailed questionnaire to be filled at the 517 farms representing the seven Lebanese districts. This survey was structured to collect informations related to the farm and the farmers, the production parameters, the reproduction parameters, the hygiene and the animal welfare. Results showed three different clusters representing the small ruminants systems in Lebanon and indicated on this thesis as “intensive system” 5 farms with a herd size of 740 ± 707 head, “semi-intensive system” 246 farms with a herd size of 145 ± 109 head and “extensive system” 266 farms with a herd size of 200 ± 152 head. Results concerning the effect of rearing systems on the reproduction of sheep and goats in Lebanon showed a weight at birth of kids and lambs varying from 3.9 Kg to 5.4kg between the different rearing systems. Prolificacy was 1.11 and 1.27 in the extensive system, 1.28 and 1.40 in the semi-intensive system and 1.79 and 1.77 in the intensive system for sheep and goats respectively. Fertility recorded 88%, 85 and 80% in the intensive, semi-intensive and extensive systems respectively. First lambing occurred at 12 months in the intensive system, 20 months in the semi-intensive and 21 months in the extensive for both sheep and goats. The average milk yield of ewes in intensive flock was 336.7 l/year, ewe in semi-intensive and extensive system produced 163.5l/year and 129.9l/year respectively (p<0.005). Flocks raised in the Bekaa district showed the lowest milk production compared to the other districts in the three rearing systems, significantly in the intensive and extensive systems. Goats raised in intensive system showed high annual milk yield 587.5 L/year. Annual milk production was significantly (p<0.005) affected by the rearing system with goats raised under semi-intensive system producing more milk (198.7 L/year) than those raised in the extensive system (133 L/year).
Animal welfare was studied in six semi-intensive and extensive farms to evaluate the effect of different stressors on the animals: environmental, physical, nutritional, management, pathological and psychogenic stressors. Cardinal physiological parameters were within the normal range for the small ruminants raised in semi–intensive systems during both winter and summer periods. The extensive system results, showed a high values of the pulse rate and the breathing score (107.55 ± 3.67 and 1.38 ± 0.49 respectively) during the summer period at noon when goats and sheep were exposed to high temperatures in direct sunlight. Sheep and goat houses were often inadequate in terms of design, materials and size. During May, small ruminants raised in both extensive and semi-intensive system, showed the higher body score condition (3.45 and 3.3 respectively). In extensive system, BCS declined during the summer period to reach a 2.4 score in September. While in semi-intensive system BCS maintained the same score during July and decreased to a score of 2.8 in September. BCS increased in November (around 3.15) for both systems and decreased again during January and March with a more expressive trend in the extensive system. Dehorning is practiced in a limited way in both semi-intensive and extensive system (7% and 10% respectively when needed).
The third experiment focused on the Bio molecular Study of the Melatonin receptors. 338 blood samples from 9 farms of local multiparous sheep (n=164) and goats (n=174) with a regular cycle, similar body condition score and similar average productivity, were collected using 2.5ml EDTA tubes in duplicate and directly refrigerated. Samples were frozen and transmitted with dry ice to the veterinary department in Sassari for DNA extraction and PCR analysis. Data concerning production and reproduction of the sampled animals were recorded. In all the analyzed sheep samples amplification products resulted in a single fragment of 824-bp in length that correspond to the entire MTNR1A exon II. Also in goat samples PCR evidenced a single band of 824-bp in length, corresponding to the MTNR1A exon II, according to the newest goat reference sequence ARS1 - Capra hircus melatonin receptor type 1A gene – GenBank assembly accession number: GCA_001704415.1. The allelic and genotypic frequency at the position g.17355458C>T found in the Awassi sheep showed a high frequency of the C allele and of the genotype C/C. The two most representative SNPs of the MTNR1A gene in the Awassi breed did not show any association with reproductive seasonality. The very limited variability found between the two breeds of goats analyzed in this research, does not make it possible to investigate the relationship between melatonin receptor polymorphism and reproductive seasonality.
To work in a sustainable perspective, it is highly suggested to keep the entity of each system with improving the zootechnical and welfare operations to valorize the natural rangelands and benefit from the native breeds characteristics and potentials
Characterization of local tomato varieties (Solanum lycopersicum L.) to promote their valorization and identify new production paths
No full textThe conservation and characterization of landraces play key role in the preservation of agrobiodiversity. In particular, they can contribute to food security and improve food nutrition, their use in local markets can provide to the sustainability of rural communities and satisfy both farmers and consumer demands.
Accordingly, in the present study a collection of tomato (Solanum lycopersicum L.) Sardinian landraces were characterized and assessed in comparison to vintage and modern varieties for evaluating: a) the response of the local varieties to the greenhouse conditions during the autumn/winter season and adopting modern horticultural techniques; b) the diversity of the collection based on morpho-phenological, metabolic and genetic data; c) their response to storage and the changes in their quality characteristics; d) the willingness to pay of consumers for local tomato varieties rather than commercial varieties.
Results revealed that the collection is characterized by a high diversity for numerous morpho-phenological and quality traits, allowing to outline the main characteristics that are in a close relationship with the fruit nutritional and commercial value. Moreover, it emerged the consumers willingness to pay high premium prices for local tomato varieties. All these results could be useful to valorize these local tomato varieties in future breeding programs and to plan strategies to support their cultivation and commercialization in regional and national markets
Heterologous expression, bioreactor production and characterization of rKPKT: a ready-to-use antimicrobial compound of interest for the wine industry
No full textThe research activities here presented were carried out within the frame of “Programma Operativo Nazionale FSE-FESR Ricerca e Innovazione-Azione I.1-Dottorati innovativi con caratterizzazione Industriale” granted by the Italian Ministero dell‘Istruzione, dell’Università e della Ricerca (MIUR). This program aims at bridging the gap between University and industry by strengthening the collaboration among academic and industrial partners for the development of innovative solutions that contribute to the growth of specific productive sectors. The academic partners involved in the realization of this theses were the University of Sassari (Sassari, Italy) and the Brno Technical University (Brno, Czech Republic). The industrial partner was the Tenute Sella & Mosca S.p.A. This is the biggest winery in Sardinia (7,6 milioni bottles/year), strongly interested in searching for innovation of processes and products and in the technological transfer of innovation. In particular, this winery has been producing organic grapes for 4 years and is interested in the development of natural antimicrobials to be utilized in the wine industry.
Based on that, and on the expertise on killer toxin characterization and exploitation acquired by researchers in the Laboratory of Microbiology of the Department of Agraria (University of Sassari), the general objective of this research was to explore the biotechnological potential of yeast killer toxins to be used as natural antimicrobials for the control of wine spoilage yeasts. In fact, although the antimicrobial activity of yeast killer toxins has been known for more than 50 years and many different authors have hypothesized their exploitation in the food and wine industry, their biotechnological potential has never been really explored. Previous works carried out in the Laboratory of Microbiology of the Department of Agriculture of the University of Sassari have contributed to shed light on the properties, mode of action and genetic determinant of Kpkt, a killer toxin produced by the yeast Tetrapisispora phaffii that has an extensive antimicrobial activity on wine spoilage yeasts. Based on these works, it was hypothesized a future for this toxin as natural antimicrobial in the wine industry where it can partially substitute sulphur dioxide thus reducing the final amount of this antimicrobial in wine. For that, considering that T. phaffii produces rather low amount of Kpkt, previous works showed that Komagataella phaffii, formerly Pichia pastoris, can be a suitable host for the heterologous production of the toxin.
In this context, specific objectives of this research were: i) the development of further molecular tools for the production of recombinant (rKpkt) in K. phaffii; ii) the bioreactor production of rKpkt and its purification and characterization; iii) the production of a ready-to-use rKpkt containing preparation, and the evaluation of its effect on a variety of biological targets.
After a review of the literature regarding natural antimicrobials and killer toxins, and K. phaffii as a host for heterologous expression in the introduction (chapter 1), and the description of the aims of the PhD thesis (chapter 2), the research activities carried out in the three years program are reported as follows.
Chapter 3 regards the construction of new vectors for the heterologous production of rKpkt. For that, Kpkt coding sequence, optimized for the expression in K. phaffii, was cloned under the control of regulated (AOX1) or constitutive (PGK1) promoters and downstream of two different secretion signals (S. cerevisiae α-Factor and the T. phaffii native secretion signals). The resulting plasmids were transformed into K. phaffii strains GS115 and M12. Screening of transformants indicated that the integration of the expression cassette results in a low percentage of 2 recombinant clones showing killer activity. In fact, contrary to native Kpkt, recombinant version Kpkt (rKpkt) is toxic for K. phaffii GS115 and M12, while showing lower toxicity on recombinant killer clones.
Chapter 4 reports on the bioreactor production and characterization of rKpkt. For that cultivation of recombinant clone#17 (rc#17) and the production of rKpkt were scaled up from baffled flask to bioreactor and rKpkt purification was attempted by immobilized metal affinity chromatography. Moreover, after having confirmed that rKpkt maintains β-glucanase activity and shows a wider spectrum of action in respect to its native counterpart, its cytotoxic effect on human cells was evaluated. Results obtained showed that rKpkt has limited toxicity to HaCaT cell line for concentrations up to 18 AU/ml thus corroborating the great potential of this toxin as a natural antimicrobial for use in the food and beverages industries.
Chapter 5 regards the production of a lyophlized ready-to-use rKpkt preparation (LrKpkt) and the evaluation its effects in grape must and on a variety of biological targets. Results showed that LrKpkt maintains its killer activity for up to six months at 4 °C and it is easily soluble in sterile distilled water. When added to Cannonau and Vermentino grape musts LrKpkt inhibited the wild microflora, while showing limited or no effect on inoculated wine yeast starters. Moreover, besides being active on wine-related yeasts, LrKpkt exerted a strong microbicidal effects on a variety of bacterial species (lactic acid bacteria and food-borne pathogens). On the contrary, in accordance with its limited toxicity on HaCaT cell line, LrKpkt showed no lethal effect on Ceratitis capitata and Musca domestica, thus suggesting its low or null toxicity on multicellular eukaryotic model organisms. Indeed, additional studies are needed to further characterize LrKpkt. Nonetheless, the results here presented suggest that this ready-to-use antimicrobial compound may represent an interesting option for the management of microbial contaminations both in the wine and food industries. In chapter 6 challenges and perspectives on the topic treated are reported.
In conclusion, the results here presented report on Kpkt heterologous production in K. phaffii, the possibility of producing a ready-to-use antimicrobial compound containing rKpkt and its low or null toxicity on higher Eukaryotic cells. Considering that the scarcity of studies regarding the effects of killer toxins on human consumers represents a constraint to their utilization in the food and beverages industries, these results, although preliminary, represent a further step towards the biotechnological exploitation of yeast killer toxins
Società e cultura nelle comunità urbane latinofone nella Moesia Inferior tra Augusto e Diocleziano
No full textThis thesis is devoted to the phenomenon of urbanization and municipalization of Moesia Inferior, a Danubian province of the Roman Empire (today northern Bulgaria and Romanian Dobrudja). Through epigraphical and archaeological sources, this work analyzes the social, administrative and religious framework of six Latin-speaking cities founded along the Lower Danube: Oescus, Novae, Durostorum, Tropaeum Traiani, Troesmis, Noviodunum. The work consists of two main sections: after a first part dedicated to the history of the province, a second section is devoted to the cities. It has been possible to define the origin and the development of urban communities, their population, the social, political, and economic relations with Western Pontic Greek cities and other Danubian provinces, the relationship between Romans and indigenous people, the contribution of immigrants and soldiers, the influence of imperial officials and of local ruling class, the process of acculturation and latinization
Grain quality traits and bread-making characteristics of old and modern Italian durum wheat varieties grown under low input conditions in a Mediterranean environment
No full textFollowing the boom in durum wheat breeding, ancient wheats disappeared from the human diet and old durum wheat varieties were replaced by what is believed to be their better versions: higher yielding modern varieties grown in high input systems. Although breeders have worked intensely ever since to improve the quality of durum wheat traits, mainly gluten subunit alleles, in order to obtain a superior technological quality of the main durum wheat end products (first pasta and then bread), conflicts about predicting their quality still exist; this is because quality is neither governed by one trait alone nor conditioned by a single controllable factor. In the first chapter of the thesis we discussed the evolution of ancient to old and then modern durum wheat varieties in terms of agronomy, genetics, technological and end-product qualities. Moving from ancient to modern durum wheat varieties, grain yield increased, grain proteins concentration decreased, gluten strength and dough toughness improved ameliorating the quality of pasta but decreasing the durum wheat versatility.
Nowadays, old durum wheat cultivars are attracting renewed attention due to their interesting genetic diversity and their suitability to low input agricultural systems where the higher yield potential of modern cultivars cannot be achieved. Consumers interest in old varieties is also growing due to the desire to revert back to traditional and organic products perceived to be ‘safer’ and ‘healthier’ foods. Old durum wheat cultivars were used for bread-making since the beginning of its practice dating back to 500 BC and durum breads are still diffuse throughout the Mediterranean region and especially in the south of Italy. In the first experiment conducted, the agronomic and bread-making performances of fourteen old Italian durum wheat varieties grown under two low nitrogen inputs (46 and 86 kg ha-1) were determined and the relationships among grain, semolina, dough and bread quality parameters were established. The old varieties yielded similarly to the check modern variety Svevo under both nitrogen levels. Increasing nitrogen fertilization from 46 to 86 kg ha-1 did not increase grain yield or the mg of N in the grain, although grain protein percentage increased due to a decrease in grain weight and increase in gliadin content. Despite a resulting decrease in the gluten index, dough and bread quality improved at the higher N rate, highlighting the influential role of protein percentage and gliadin in bread quality. The genotypic variation in grain protein percentage among old varieties was more strongly associated with glutenin than with gliadin content. Variation in the gluten index was high (4-54), indeed it was the most variable semolina parameter, and proved to contribute the most to variation in bread quality. This variation was independent of the glutenin alleles (HMW 20, 20*, 7, 13+16, 6+8) and was linked to the quality of the grain in terms of grain weight and the associated mg of N per grain. Remarkably, two old varieties, namely Calabria and Cappelli, were able to produce both a good yield and high quality bread.
In the second experiment conducted, fourteen old and two modern durum wheat cultivars were analyzed in two field trials at two nitrogen (N) levels (46 and 86 Kg N ha-1) to assess the effect of grain number and N absorbed and translocated by the crops on grain protein percentage and whether the genotypic variation in grain N was associated with a variation in the quantitative ratios between the various protein fractions.
Mean grain yield was below 3 t ha-1 and strongly associated with the corresponding variation in the number of grains m-2 (GNO) (r = 0.93***). The greater amount of N present in the biomass of old cultivars at anthesis, due to their greater biomass (r = 0.87***), resulted in a greater N source for the growing grains (15-23 g m-2) compared with modern cultivars (13-16 g m-2) despite the greater post-anthesis N uptake of modern cultivars. In spite of this larger source, most old cultivars generally delivered a lower amount of N m-2 (4.1 - 8.5 g m-2) to their mature grains compared with modern cultivars (8.1-10.3 g m-2). Nevertheless, their lower GNO resulted in a greater amount of N in each grain, which was the main determinant of their higher grain protein percentage (r = 0.81***).
Genotypic variation in grain N content correlated with a variation in the content of all three protein fractions (albumins-globulins, gliadins and glutenins) but the strength of the correlation with gliadin and albumin-globulin was higher than that with the glutenins. Genotypic variation in gliadin and glutenin content was more tightly correlated with the variation in the sulphur-rich protein groups and subunits (alpha/beta, gamma and low molecular weight glutenin subunits) than with the sulphur-poor protein groups and subunits. The significant genotypic differences in the ratios GLI/GLU, Srich/Spoor and HMW/LMW were not influenced by the corresponding variation in grain N content, even when the slope of the regressions for the two terms of the ratios against the total, as in the case of HMW and LWM, were different. The final N content can only explain part of the variation in the quantitative ratios between fractions and components since genotypic differences other than grain N content also contribute to these variations
Different vineyard management practices: agronomic responses and consequences on must quality
Full text linkBackground and Aims
Global warming has repercussions on vine phenology and physiology, with consequences affecting yield and berry composition. In order to counteract negative effects, it is necessary to improve the knowledge on genetic aspects as well as vineyard management.
The aim of this study was to evaluate the responses of different Vitis genotypes to several agronomic practices, such as water management, the application of exogenous abscisic acid (ABA) as well as leaf removal, all of which influence the ripening process.
Methods and Results
Two experiments were carried out. In the first one, conducted in Sardinia (Italy), different strategies of water stress and exogenous ABA application were tested on three red grapevine cultivars. In the second trial, carried out in Australia, a leaf removal treatment, performed post-veraison, was compared with no defoliation treatment on two grapevine cultivars.
Conclusions
Water stress response is cultivar-dependent. No significant effect or interactions were observed by applying exogenous ABA.
Leaf defoliation above the bunch zone reduced sugar accumulation rate in the berries, causing a delay in harvest of 24 days, although observed only in one of the two investigated varieties.
Significant of study
This study points out the importance of the deep knowledge of the genetic background of each specific cultivar, highlighting how the different cultivation techniques can play a fundamental role in influencing the berry maturation