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Intra-articular pressure determination in horse
Get PDFThe aim of the present study is to evaluate the intra-articular pressure in horses with distal forelimbs chronic lameness in order to obtain indication about the\ud
diagnostic significance of pressure variations. Fifty-six distal interphalangeal (DIP) joint of the forelimbs of 36 horses were investigated by a clinical and radiographic examination and by measuring the pressure with a hand held digital manometer. Forty coffin joints of sound horses were used as a control. The pick pressure was registered for each articulation. The middle pressure measured with the sound horse bearing weight on both limbs was 36.8 mmHg +/-16.0 and 69.6 mmHg +/- 27.3 when the contralateral was lift up. For the diseased horse the middle pressure measured in the two position was 66.5 mmHg +/-7.6 and 132.8 mmHg +/- 43.3 respectively. This result indicates that intra-articular pressure values of the coffin joint are higher in horses with a painful condition of the distal portion of the fore foot.\ud
Anyway, our ranges resulted higher than whose indicated in other reports.\ud
No correlation have been found between articular pressure and kind of radiographic changes of the DIP joint or of the distal sesamoid bone.\ud
Pressure measurement could be considered a useful aid to localize a pathologic condition involving the DIP joint or the navicular bone, but the technique shows some limitation: it seems to be more reliable for diagnosis with both limbs weight bearing because low specificity arises with the contralateral lifted up.\ud
No weight, breed or attitude differences were detected among sound horses. No complications have been reported neither during the examinations nor through the follow-up .\ud
Pressure measurement is an easy, safe, useful and relatively cheap procedure that doesn’t need of the horse hospitalization
Gli archivi istituzionali ad accesso aperto delle università italiane. Un'indagine
No full textLa scienza e' “conoscenza pubblica” e tale e' solo se viene condivisa: la comunicazione, o pubblicita' del sapere, assume, percio', una funzione essenziale e costitutiva per il progresso. «Il principio basilare della scienza e' che i risultati della ricerca devono essere resi pubblici, le scoperte [degli scienziati] non possono essere considerate come appartenenti alla conoscenza scientifica finche' non sono state riferite e registrate in modo permanente». Da cio' deriva che ricerca scientifica e pubblicazione dei suoi risultati - da intendersi in senso lato - sono due attivita' che vanno di pari passo e che si presuppongono a vicenda: tutta la ricerca poggia sulle fondamenta costituite dai risultati certificati della ricerca passata, per fungere poi essa stessa da base per le ricerche future.\ud
Il tradizionale modello di circolazione del sapere, pero', e' entrato in crisi; occorre pertanto analizzarlo nella sua evoluzione storica, per comprendere quali sono state le\ud
deformazioni, che hanno portato alla sua instabilita', e per individuare le opportunita' di cambiamento che ogni crisi porta con se': alla trattazione di questi argomenti e' dedicato l’intero primo capitolo.\ud
Nel secondo l’attenzione si spostera', poi, su una delle due strategie previste dal Movimento per l’Accesso Aperto alla letteratura scientifica (Open Access Movement), mediante le quali mira a riportare il sistema della comunicazione scientifica alla sua originaria funzione, cioe' garantire la massima diffusione delle idee e dei risultati della ricerca il piu' rapidamente possibile e senza alcuna limitazione. L analisi si concentrera',\ud
quindi, nello specifico, sul modello degli archivi ad accesso aperto (open archives), che prevede l’auto-archiviazione da parte degli stessi autori dei prodotti della loro ricerca e il loro collocamento in rete secondo criteri tecnici e legali ben definiti, che ne garantiscono la disponibilita'. In particolare ci si occuperà di archivi aperti istituzionali, per i quali verra' proposto un piano operativo per la loro realizzazione.\ud
Nel terzo capitolo si cerchera' di fare un bilancio della situazione italiana con un taglio prevalentemente storico, che ricostruisca gli eventi e riassuma le prese di posizione assunte a livello istituzionale che hanno inserito l’Italia a pieno titolo nel contesto internazionale. A questa ricostruzione seguiranno alcune brevi considerazioni sulle iniziative intraprese a sostegno dell’Open Access – riviste open access, open archives e university press.\ud
Il capitolo conclusivo, infine, e' dedicato all’illustrazione dei risultati dell’indagine condotta sugli archivi istituzionali ad accesso aperto delle universita' italiane. Lo scopo e' stato quello di verificare quanto di effettivamente concreto sia seguito alle dichiarazioni formali espresse dalla comunita' accademica italiana a sostegno dell’open access. Per farlo si e' utilizzato lo strumento del questionario, nel\ud
tentativo di mettere in luce i progressi ottenuti, le criticita' incontrate e i possibili sviluppi
Microbial and enzymatic biodegradability of composite materials from fiber glass acrylic filters
No full textBio-degradability of composite materials from fibre glass acrylic filters which are utilized in air conditioners can provide the basic information to recycling process in manufacturing. The filters of out of quality control were required to recycle for getting glass fibre which was imported to Italy. Current running method is burning at high temperature (800ْC) to remove the organic composites materials. Five fungal species and two strains of bacteria were utilized. They were Trichoderma harzianum (2 strains), Trichoderma koninggi, Penicillin spp, Aspergillus niger, Pseudomonas aeruginosa, and Pseudomonas fluorescens. Pre-sterilized filters were incubated in NSAM agar medium and M-3 biodegradation medium at 28°C for 21 days. Biodegradability was monitored by rating scale of microbial colonization, gravimetric measurement, and weight losses of filters coupons and by Scanning Electron Microscopy analysis. Among the species under investigation, Trichoderma harzianum MYA198 showed the best performance in both results of weight loss measurement, (up to 70%) and direct visualization by SEM. The degradation was analysed by total carbon analysis of degraded filters and esterase activity assay, using ρ-nitrophenyl acetate. Our results clearly indicate that cells grown in the presence of shredded filters as carbon sources display a greater hydrolytic activity compared to control.\ud
\u
EFFECT OF N-ACYLETHANOLAMIDES ON PLASMA LIPID\ud PEROXIDATION AND PARAOXONASE ACTIVITY: AN IN VITRO STUDY
No full textN-acylethanolamides (NAEs) are naturally occurring hydrophobic molecules, present in mammalian tissues and biological fluids, such as plasma. Previous studies showed\ud
that some of these molecules have protective properties against oxidative stress in some cell models. The present study was designed to determine whether NAEs, differing for acyl chain length and unsaturation, can have a protective effect on the oxidative susceptibility of plasma lipids, that is considered a factor contributing to atherogenic risk. To study the effect of three different NAEs on free-radical induced damage of plasma lipids, conjugated dienes and lipid hydroperoxides formation was investigated by incubating unfractionated plasma with radical generators (Cu2+ and/or AAPH). Moreover, the effect of these NAEs on the in vitro induced oxidative degradation of PON1 activity was measured, in unfractionated plasma. PON1, an enzyme associated with plasma high density lipoproteins, plays an important role against oxidative damage of lipoproteins and in protection against atherosclerosis.\ud
Results obtained demonstrated that the NAEs used oleoylethanolamide, palmitoylethanolamide and anandamide) elicited a significant protection against both AAPH and copper-induced plasma lipid hydroperoxides increase or oxidative decrease of PON1 activity. The protective effect was shown also on the conjugated dienes formation induced by incubation of diluted plasma with CuSO4. Among the three NAEs used, the largest protective effect was shown by 1 µM anandamide (AEA) that induced a 32.6% decrease of lipid hydroperoxides concentration, with respect to control sample, in undiluted plasma incubated with 20 µM CuSO4.\ud
Our results suggest a possible protective role of NAEs in the pathogenesis of diseases associated with oxidative stress
The complete sequence of the iceman's mitochondrial DNA
No full textThe so-called Tyrolean Iceman or Similaun Man or Ötzi is perhaps the most famous human mummy in the world. The body was discovered on 19th September 1991 on the Eastern Alps at 3270 m above sea level, near the austro-italian border. Radiocarbon dating of the remains, performed soon after the\ud
discovery, indicated an age of 5350-5100 years before present. One of the most interesting features of the find is the exceptional state of preservation of the body and of the pieces of equipment found nearby. This phenomenon is attributed to a spontaneous freeze-drying process. At the time of his death the man was approximately 46 years old and, according to the most recent forensic reconstructions, he was hit by an arrow in the left shoulder then finished off with a mace blow on the face.\ud
The first part of the thesis (Paper I-II) is focused on the determination of the mummy’s mitochondrial haplogroup. The European mitochondrial DNA is currently divided into nine (H, T, U, V, W, X, I, J, and K) main groups (haplogroups). The K haplogroup, in particular, is composed of two (K1 and K2) subclusters. The present study demonstrates that the Iceman’s mtDNA belongs to the K1 subcluster, yet it does not fit any of the three known branches (a, b, and c) into which the K1 subcluster is presently divided.\ud
In the second part (Paper III) the complete sequence of the mummy’s mitochondrial DNA is determined through a mixed procedure taking advantage of ordinary polymerase chain reaction (PCR) amplification and innovative 454 pyrosequencing technology. This part of the study has required to carry out 236 PCR amplifications and analyze over 42,000 sequences, generated by the pyrosequencing\ud
process. The results have revealed the presence of 30 transitions in the mummy’s mitochondrial genome compared to the Cambridge Reference sequence (CRS).\ud
The third part of the thesis (Paper IV) is devoted to the characterization of post-mortem damage in the Iceman’s mitochondrial DNA with a particular emphasis on the so-called Type 1 (A.G/T.C) and Type 2 (C.T/G.A) damage. The results demonstrate that Type 2 miscoding lesions represent the overwhelming majority (88%) of damage in the Iceman’s DNA. Type 1 miscoding lesions, on the other hand, are relatively rare and seem to arise from polymerase errors.\u
Oligomerization Dynamics of the E. coli Nucleoid Protein H-NS on its target DNA\ud
No full textFor many years H-NS has been considered as a DNA-binding protein without a sequence specificity, having a role of nucleoid structuring protein with a global effect on gene expression.\ud
The capacity of H-NS to repress a wide range of genes was attributed to its characteristic of recognizing and preferentially binding AT-reach sequences, and intrinsically curved DNA.\ud
Recently, quantitative analyses of the H-NS binding sites at the E. coli proU promoter, has demonstrated that H-NS recognizes a 10bp sequence with a high affinity. Moreover, comparing footprints results obtained by the binding of the isolated C-terminal domain of H-NS (responsible for the binding capacity) on five different target promoters (Stella S. Ph.D Thesis, 2005), and combining footprinting data from different sources, an H-NS binding motif has been found. The derived motif was used to predict potential binding sites, and these predictions were confirmed by following footprinting analyses.\ud
However the existence of specific binding sites for H-NS, only partially explains the silencing effect of H-NS on different promoters.\ud
A proposed model, to explain the mechanism by which H-NS silences extended regions of DNA, suggests that the protein nucleate at high-affinity sites located in the core promoter of target genes, and subsequently it spreads along secondary sites of lower affinity. In this way the protein\ud
occupies the promoter region and allows the formation of nucleoprotein complexes of higher order structure.\ud
In this project we wanted to analyze the fundamental steps of H-NS/DNA interactions from a dynamical point of view, to understand the molecular mechanisms leading the oligomerization of H-NS along its target DNA, in a temporal resolution. For this purpose we set up a series of\ud
quantitative time-resolved DNaseI footprinting assays.\ud
We used a KinTek quenched-flow apparatus, that allows the analysis of the association of a protein on its target, at increasing times of protein/DNA interaction.\ud
Since H-NS protein directly affects the expression of its own gene, as target DNA we used the natural hns promoter from E. coli. We also investigated the kinetics of H-NS binding upon a DNA fragment, where the isolated H-NS binding motif was introduced into a portion of the\ud
Tetracycline Resistance gene, for which H-NS has a general low affinity.\ud
Moreover we compared time-resolved data with equilibrium footprinting assays carried out using the isolated C-terminal domain, responsible for the DNA binding.\u
Actiones adiecticiae qualitatis: categoria dogmatica o nomen iuris?
No full textIl lavoro riprende la tematica “classica” delle actiones adiecticiae qualitatis, focalizzando un problema che è ancora al centro della discussione scientifica, quale l’origine e il significato del termine adiecticiae qualitatis. In equilibrio tra la prospettiva dogmatica e quella storica, l’Autore analizza il concetto di “adiettizietà” delle azioni a tutela dei terzi che contraevano con personae alieni iuris, rilevando come l’uso dell’etimo adiecticiae qualitatis sia assente nel pensiero giurisprudenziale romano e nasca in seno alla Scuola dei Glossatori sulla scorta di un’equivoca interpretazione di un testo paolino contenuto nei Digesta (D.14.1.5.1). Il confronto tra l’utilizzo del termine e i meccanismi che regolano la tutela adiettizia fa approdare la ricerca a una spiegazione etimologica alternativa delle actiones adiecticiae qualitatis, già elaborata dalla Pandettistica tedesca, in grado di sciogliere l’interrogativo posto nel titolo
Lewis acids in the preparation of the heterocyclic compounds: synthesis and characterization of the impurities of API
No full textThe work reported on this thesis is the result of a collaboration between the University of Camerino and the Pfizer of Ascoli Piceno.\ud
This collaboration includes, but was not limited to, the confirmation of molecular structure of reference standards. The Reference Standard’s Group supports manufacturing by certifying standards which are then used in the analysis and evaluation of a new lot of an active pharmaceutical drug. Due to the potential significant impact to manufacturing, in many cases a full study is needed to confirm the structure of the standards.\ud
Another interesting scientific aspect of this collaboration has been the synthesis of impurities. It is known that the impurities in an Active Pharmaceutical Ingredients (API) may arise from degradation of the API itself, which is related to the stability of the pure API during storage, and the manufacturing process, including the chemical synthesis. Process impurities include unreacted starting materials, chemical derivatives of impurities contained in starting materials, synthetic by-products, and degradation products. Then, impurities have to be monitored on the active pharmaceutical “parent” drug and a reference standard is often needed to determine the quantity of impurities and/or to confirm their structure without any doubt. The best approach to obtain an impurity is probably an synthetic approach which utilizes an alternative chemical pathway to get the desidered compound, and, given that it is estimated that more than 70% of all pharmaceutical products possess heterocyclic structural submits, our efforts have been focused on the development of new bond-forming reactions in the heterocyclic polyfunctionalized molecules.\ud
Parallelly, my thesis represents a contribution to the program of the research group of the Department of Organic Chemistry of the University of Camerino, that, for a long time, has focused the attention on the study of the catalytic activity of Lewis acids, such as TiCl4, and particularly the CeCl3. In fact, our research group has dedicated itself particularly to the study of new methodologies involving the use of CeCl3·7H2O-NaI system as a promoter that facilitates a variety of useful organic transformations. In many trials good results have been achieved and the procedures developed are characterized not only by the efficiency of the reactions, but also by selective processes, by a good stereochemical control, by reacting available and inexpensive reagents and in some cases from the possibility of recovering the cataliytic promoter system used through simple procedures of work-up. For this reason, we have explored the reactive possibilities of the CeCl3·7H2O-NaI system with the goal of developing some simple and efficient procedures for the synthesis of heterocyclic compounds that introduce biological activity or that can be used as building blocks for the synthesis of more complex molecules. Attention, furthermore, was focused on the use of the CeCl3·7H2O-NaI system on a silica gel surface under solvent-free conditions for the synthesis of molecules with interesting pharmacological properties.\u
Electrochemical and spectroscopical characterization of keggin type polyoxometalates: H3PW12O40 and H3PMo12O40\ud and their cesium and ammonium salts. Applications for hydrogen oxidation reaction
No full textThe purpose of this thesis is the study of Keggin polyoxometallates H3PW12O40,H3PMo12O40 and cesium and ammonium salts, used by our research group as catalysts for\ud
Polymer Electrolyte Membrane Fuel Cells (PEMFC).\ud
First we realized a preliminary study of electrochemical behavior of these compounds by different voltammetric techniques (cyclic voltammetry, differential pulse\ud
etc.) and then we used spectroelectrochemical methods in order to clarify their redox behaviour. Adsorption on electrodes surface was studied as well\ud
The acid may be used to modify the surface of Pt nanoparticles obtaining efficient catalyst for hydrogen oxidation reaction (HOR). However, because of the solubility of the acids in water the catalytic activity is time dependent and their utility as catalysts in fuel\ud
cells decreases. In order to overcome this problem, we decided to synthesize the cesium and ammonium salts that are water insoluble. The prepared salts have been characterized morphologically and electrochemically. One of these, Cs2.5H0.5PW12O40, is proposed as matrix for dispersion of platinum catalyst.\u
New Developments on CeCl3-Promoted Reactions in the\ud Synthesis of Heterocycles
No full textSynthetic chemistry is the science of constructing complex molecules from simpler ones, and one of the most important developments in this area of research is the total synthesis of biologically or pharmaceutically interesting molecules. In synthetic organic chemistry, the term total\ud
synthesis refers to the step-by-step design of the chemical synthesis of a molecule, usually a natural product, from relatively simple and hopefully cheap and commercially available starting materials.\ud
“There is excitement, adventure, and challenge, and there can be great art in organic synthesis” said Woodward in Perspectives in Organic Chemistry about total synthesis.\ud
While challenge and adventure are some of its exciting characteristics, organic synthesis is founded on the systematic study of a strategy and a tactic, and is achieved by a scrupulous retrosynthetic analysis.\ud
As a field, organic synthesis can be divided into two major areas: total synthesis and methods-oriented synthesis. The investigation, discovery, and development of new synthetic reactions, reagents, and catalysts are grouped under the second area, known as synthetic methodology.\ud
Total synthesis is almost always the synthesis of natural products because of the great importance of these compounds in biological, medicinal and pharmaceutical sciences. As Corey said: “Nature continues to be exceedingly generous to the synthetic chemist in providing ample opportunity for discovery and creative endeavor of highest magnitude and\ud
in surrounding him with an incredible variety of fascinating and complicated structures”; nature is a continuous source of molecules with intricate structures and pharmaceutical properties for the research chemist\ud
to reproduce in the laboratory.\ud
Even if in the classical era of organic synthesis the purpose of a total synthesis was to confirm the molecular structure of a natural product, now other reasons for total synthesis have arisen. Amongst the most important are: a) the challenge, often irresistible to those who appreciate\ud
and practice the art, of synthesizing a naturally occurring substance of novel architecture; b) the opportunity to discover and develop new synthetic chemistry that will solve not only the problem under consideration, but also problems of broader interest; c) the ability to make contributions in biology by providing not only the natural substance but also by making available designed molecules that may mimic or inhibit the action of the natural product.\ud
Every year many natural products are isolated from plants,\ud
microorganisms, etc. and the challenge for organic chemists is to study new approaches to make them quickly and efficiently, while pharmaceutical and medicinal chemists are interested in exploiting their biological and\ud
pharmaceutical properties.\ud
The Marcantoni research group has been interested in both fields of organic synthesis: the total synthesis and the development of new synthetic methodologies. In the past years, the Marcantoni group has focused their interest not only on the total synthesis of small biologically active molecules, and of useful building blocks for the synthesis of antibiotics and natural products;4 but also on the development of new methodologies involving the use of the CeCl3⋅7H2O Lewis acid, especially in combination with NaI, as a promoter system in carbon-carbon and carbonheteroatom\ud
bond forming reactions.\ud
This thesis work is borderline between these two fields of interest, as illustrated by the different nature of the projects it is comprised of the study of a new approach to the total synthesis of (+)-furanomycin, and the total synthesis of Climacostol, constitute the total synthesis portion of this work, while the syntheses of polyhydroxyalkyl furans and of alkyl 9H-\ud
β-Carboline-4-carboxylate are part of a broader study on the use of the CeCl3⋅7H2O-NaI combination as a promoter system in organic synthesis. [...]\ud
In the first project we developed a new strategy for the total synthesis of (+)-furanomycin involving the synthesis of a useful building block for the natural antibiotic by nucleophilic addition of an organocerium compound to the (R)-Garner-type aldehyde. In the second project, the Lewis acid CeCl3⋅7H2O was used in combination with NaI to promote the Knoevenagel condensation between sugars and 1,3-diones to give polyhydroxyalkyl furans. The third project focused on the use of the CeCl3⋅7H2O-NaI system to promote the Michael addition of indoles to nitroalkenes to then use\ud
the Michael adducts thereby obtained as building blocks in the synthesis of β-Carboline derivatives. (+)-Furanomycin, polyhydroxylalkyl furans, and β-\ud
Carbolines are all heterocyclic compounds. In particular, (+)-furanomycin and polyhydroxylalkyl furans are heterocyclic compounds containing a 2,5-\ud
dihydrofuran ring and a furan ring, respectively. In Chapter 1 are reported a few examples of molecules illustrating the widespread presence and importance of furan, dihydrofuran, and tetrahydrofuran moieties in the\ud
core structure of naturally occurring substances. The project on the total synthesis of Climacostol, a natural product of great interest for its biological and pharmaceutical properties, was initiated because, although a\ud
small molecule to date no efficient protocol for its total synthesis has been reported.\ud
The third project was carried out in the Ciufolini group at UBC. The Ciufolini group is skilful and experienced in the retrosynthetic analysis and in the total synthesis of big and complex molecular structures. Among the many research avenues pursued in the Ciufolini group, the work here\ud
presented was part of their project on the synthesis of tetrodotoxin. One key step in the Ciufolini approach to the total synthesis of the potent neurotoxin is an asymmetric Henry reaction and this work focused on the synthesis of the chiral ligand for the copper catalyst used in the\ud
asymmetric step.\ud
Since most of the natural products we are interested in contain heterocyclic rings a brief overview on the presence of heterocycles in nature is presented in Chapter 1, with an emphasis on the oxolane ring structure