1,721,145 research outputs found
Il ruolo della chemioipertermia nel carcinoma del colon-retto
No full textLa carcinosi peritoneale rappresenta una delle principali modalità di diffusione del carcinoma del colon-retto.
Le metodiche chirurgiche tradizionali, così come i trattamenti chemioterapici convenzionali, hanno dimostrato una efficacia molto limitata, con sopravvivenze mediane che raramente superano i 6-8 mesi. Negli ultimi anni è stato
proposto da più Autori un trattamento aggressivo che si basa sulla chirurgia citoriduttiva, con asportazione più o
meno estesa del peritoneo interessato dalla malattia, associata alla perfusione intraaddominale di farmaci chemioterapici in ipertermia. Diversi studi hanno dimostrato l’efficacia di questa metodica soprattutto nei pazienti nei
quali è stato possibile ottenere una citoriduzione completa o con minimo residuo tumorale, con sopravvivenze a
cinque anni che si avvicinano al 20%. La chemioipertermia intraperitoneale, in effetti, sembra agire prevalentemente
sulla microdisseminazione peritoneale della malattia. Sulla base di questo principio, è stato da noi proposto l’utilizzo
di questa procedura a scopo adiuvante, per prevenire la recidiva peritoneale nei pazienti a rischio (citologia
peritoneale positiva). Il trattamento si associa ad un rischio molto elevato di complicanze post-operatorie, e necessita
pertanto di una adeguata selezione dei pazienti e deve essere effettuato esclusivamente in Centri specializzati
Evaluating physical pre-treatment methods for improving insect chitin hydrolysis using Streptomyces griseus chitinase
No full textChitin and particularly its derivatives, chitosan and chitoligosaccharides (COS), are gaining interest as highly functional biopolymers with many applications. Chitin, the main component of the exoskeleton of crustaceans and insects, has a resistant structure that makes access to chitinolytic enzymes extremely difficult, thus limiting the possibility of obtaining COS. Therefore, several pre-treatments have been investigated to interfere with the crystalline organisation of chitin and improve its enzymatic hydrolysis. This study tested different physical pre-treatment methods (ultrasonication, mechanochemical milling, and the use of pulsed electric fields) on different insect species (Hermetia illucens, Acheta domesticus, and Tenebrio molitor) compared to shrimp shells, aiming to intensify COS formation through the hydrolysis of the whole insects with chitinase from Streptomyces griseus. The findings of this study highlighted the importance of pre-treatments in enhancing the enzymatic hydrolysis of chitin and suggested the potential of insect-derived chitin as a sustainable source for COS production. In particular, different insect species produced different amounts of N-acetylglucosamine and N,N’-diacetylglucosamine, and mechanochemical pre-treatment on Hermetia illucens was the most effective. Additionally, this insect also had a lower degree of acetylation, calculated by 1H NMR, than the other species, indicating a possible influence on enzyme activity
National guidelines and evidence based medicine
No full textIn the international scenario of evidenced based medicine oncologic treatments are crucially involved, since clinical trials are of utmost importance in oncology and levels of recommendations are their direct consequence. As for the majority of cancers, the result of evidence based medicine in gastric cancer field is very often a guide-lines document. Such a consensus file is mostly reached within national associations of specialists dedicated to the treatment of gastric cancer. The aim of our web round table is to try to compare many of these national guide-lines, contacting their own Authors and to have a feed-back for all the users of them on how much these guide-lines are useful and followed in every single country. Our objective would like to be not a scientific discussion on the single topics expressed in the guide-lines, but how such guide-lines were defined, how much evidence based medicine was crucial in this definition and if it could be possible to extend this way of take steps from a national setting to an international scale
It is time for a proper staging system for adenocarcinoma of the gastroesophageal junction.
No full textAbstract not availabl
Black soldier fly as a New chitin source: Extraction, purification and molecular/structural characterization
Full text linkBlack Soldier Fly (BSF) represents a potential chitin source that has not been fully explored in terms of characterization, extraction, and purification. In this study, different chemical and enzymatic protocols with or without pre-treatment (ultrasonication and mechanochemical milling) for chitin extraction were tested. Chitin was then accurately quantified and characterized from a molecular and structural point of view by UPLC-MS, XRD, and ESEM, and compared with chitin from shrimp shells. BSF chitin was more recalcitrant than shrimp chitin during extraction and purification, due to the strong binding of chitin to proteins. Indeed, the purity of shrimp chitin was 88.3g/100g of extract, while BSF chitin purity was 47.6–79.9g/100g. Furthermore, the chitin-bound proteins had a defined amino acid composition; their binding was also confirmed by structural characterization. Therefore, the efficiency of each step of the extraction process needs to be critically evaluated to adapt the methods used for crustaceans to insect biomass
Development of a protocol for fractionating and characterising fibres from lignocellulosic food waste
No full textThis study aims to explore an advanced protocol for characterising dietary fibre (DF) fractions to meet the growing demand for accurate and reliable data. Although current enzymatic-gravimetric approaches, e.g., AOAC and Van Soest analysis, provide information about soluble and insoluble DF quantification, they present limitations related to the lack of fractions characterisation. To overcome these limitations, the proposed protocol integrates the official AOAC 991.43 method with the sequential fibre fractionation by exploiting the different resistance of the fibre fractions to acid hydrolysis treatments (TFA and H2SO4), utilising hazelnut shells as a case-study. Each hydrolysed fraction was quantified and characterised through GC–MS analysis of monosaccharides. The data obtained for hemicellulose, cellulose, and lignin fractions were then discussed and compared with the Van Soest method. This approach yields a comprehensive procedure applicable to different food and nutraceutical products, emphasising the importance of DF characterisation for a deeper understanding of their bio-functional properties
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