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Biomedical subjects

A Corradi

Publications and source records attributed to A Corradi.

At least 19 recordsLinked to original sources
PubMed2005

Glass-ceramics obtained by the recycling of end of life cathode ray tubes glasses.

This work is concerned with open-loop recycling of end of life Cathode Ray Tubes glass (an unsolved problem when considering that in Europe almost 90% of EOL electronic goods is disposed of in landfills), focusing on the development of glass-ceramics from panel or funnel glass with dolomite and alumina, and the evaluation of the tendency towards crystallisation with particular attention on composition and thermal treatment. Glasses were melted at a temperature of about 1500 degrees C and transformed into glass-ceramics by different thermal treatments (900 degrees C to approximately 1100 degrees C temperature range and 0.5 to approximately 8h soaking time). By using the evaluation of thermal, mineralogical and microstructural data it has been pointed out that a good degree of crystallisation is reached at about 1000 degrees C and with a high proportion of waste glass (50-75%) if 40-45% of CaO and MgO bearer (dolomite) is introduced. In this way alkaline and alkaline-earth silicate and aluminosilicate mainly develop probably with a surface mechanism.

Ceramics↗
PubMed2005

Isolation, purification, and heterogeneity of human lymphatic endothelial cells from different tissues.

Relatively few attempts have been made in the past to isolate and expand lymphatic endothelial cells (LECs). Recently this task has become feasible thanks to the identification of new lymphatic markers such as Podoplanin, Lyve-1, Prox-1 and D2-40. Using a two-step purification method based on the sorting of endothelial cells with Ulex Europaeus Agglutinin 1-coated beads followed by purification with monoclonal antibody D2-40, we were able to purify and in vitro expand human derived LECs from tissues such as lymph node, spleen, thymus, palatine tonsil and iliac lymphatic vessels. The isolated LECs were expanded on collagen type 1 and fibronectin coated flasks for up to 8-10 passages and then analyzed for phenotypic and functional properties. LECs were able to form a capillary like network, when seeded on Cultrex BME, indicating their capability to form lymphatic vessels in vitro. Comparative studies were performed, and we found that specific lymphatic and vascular markers were differentially expressed by LECs prepared from different sources, clearly demonstrating the phenotypic heterogeneity of LECs from different organs and different segments of the lymphatic vasculature. We here propose a new technique to make available ready sources of abundant well-characterized human LECs to examine normal profiles and behavior to compare with abnormal conditions.

Biomarkers↗
PubMed2004

Ezrin gene, coding for a membrane-cytoskeleton linker protein, is regionally expressed in the developing mouse neuroepithelium.

Ezrin is a member of the Ezrin, Radixin, Moesin (ERM) proteins family that are proposed to act as linkers between the cytoskeleton and plasma membrane. Ezrin regulates cell-cell and cell-matrix interactions playing a role in the regulation of cellular adhesion, movement and morphology in epithelia. Alterations in the expression of Ezrin and other members of ERM family have also been observed in brain tumours. Here we report the expression pattern of Ezrin during mouse neural development, from early stages to postnatal stages. In young and middle gestation embryos, Ezrin is expressed in the roof plate of the neural tube, in the presumptive domain of the choroidal plexus, and in some precise domains of ventricular epithelium. These domains are distributed in basal and alar neuroepithelial regions, some of them in relation to the expression of cadherins. At later gestation and postnatal stages, Ezrin expression is maintained on the mature choroidal plexus and is weakly detected in the proliferative regions of the mature brain.

Animals↗
PubMed2004

Ultrasonography and cystic hyperplasia-pyometra complex in the bitch.

Cystic endometrial hyperplasia-pyometra complex is the most frequent and important endometrial disorder encountered in bitches. The pathogenesis of the disease is related to the activity of progesterone [Feldman and Nelson, Canine and Feline Endocrinology and Reproduction (1996) W.B. Saunders, Philadelphia]. Cystic endometrial hyperplasia (CEH) is an abnormal response of the bitch's uterus to ovarian hormones [De Bosschere et al. Theriogenology (2001) 55, 1509]. CEH is considered by many authors to be an exaggerated response of the uterus to chronic progestational stimulation during the luteal phase of the oestrous cycle, causing an abnormal accumulation of fluid within the endometrial glands and uterine lumen (De Bosschere et al. 2001). The resulting lesions of pyometra are due to the interaction between bacteria and hormones. The aim of this study was to evaluate if transabdominal uterine ultrasonography can be a useful and reliable diagnostic method to confirm Dow's [Veterinary Record (1958) 70, 1102] and De Bosschere's histopathological classification of CEH-pyometra complex. The study was carried out on 45 bitches with pyometra, 10 purebreds and 35 crossbreeds, 1-15 years old, 20% of which had whelped at least once. None of these animals had received exogenous oestrogen or progesterone treatment. On admission the 45 animals were in the luteal phase of the oestrus cycle. Clinical signs, blood parameters, uterine ultrasonography, bacterial swabs and uterine histopathological results were recorded. Results suggest that ultrasonographic examination is a useful and reliable tool for the diagnosis of cystic endometrial hyperplasia.

Animals↗
PubMed2003

Establishment and characterization of two new pig cell lines for use in virological diagnostic laboratories.

Two pig cell lines derived from kidney and trachea tissues and referred to as newborn swine kidney (NSK) and newborn pig trachea (NPTr) were established following serial culture of primary cells. They were characterized by an epithelial-like morphology, high capacity to replicate and stability of the cell monolayer for several days after seeding. Their modal chromosome number was modified in comparison to that of primary swine cells and they both displayed a transforming potential in vitro and displayed oncogenicity in nude mice. Infection with pig endogenous retroviruses was detected. Almost all the swine viruses tested, i.e., pseudorabies virus, pig parvovirus, hog cholera virus, transmissible gastroenteritis virus of swine, encephalomyocarditis virus, swine vesicular disease virus and the enteroviruses, except pig reproductive respiratory syndrome virus, were capable of replicating in the new cell lines with titres similar to the ones detected in the reference culture systems. Furthermore, all the selected influenza virus sub-types isolated from human, swine and avian species replicated with cytopathic effect in NSK and NPTr cells, whereas, of all the equine influenza viruses tested only the Miami and Suffolk sub-types replicated.

Animals↗
PubMed2002

Laparoscopic cholecystectomy by ultrasonic dissection without cystic duct and artery ligature.

BACKGROUND: Laparoscopic cholecystectomy (LC) is the gold standard treatment of gallstones. Nevertheless, there are some pitfalls due to the limits of current technology and the use of inappropriate ligature material, with a relevant risk of injuries and postoperative, mainly biliary, complications. Ultrasonically activated scissors may divide both vessels and cystic duct, with no need of further ligature, and possibly reduce the risk of thermal injuries. METHODS: A prospective nonrandomized clinical trial was started in 1999 to test harmonic shears (Ultracision, Ethicon Endo-Surgery, Cincinnati, OH, USA) in 461 consecutive patients undergoing LC in order to evaluate the theoretical benefits of ultrasonic dissection and the possible reduction in intraoperative bile duct injuries (BDIs) and postoperative complications. Patients were divided in two groups: in group 1 (HS; 331 patients) the operation was performed by Ultracision (including coagulation-division of cystic duct and artery); in group 2 (LOOP; 130 patients) the cystic duct, after coagulation-division by harmonic scissors, was further secured with an endo-loop. Both groups were further divided into two subgroups: expert and surgeon-in-training. The following categories of data were collected and analyzed: individual patient data, indication for laparoscopic cholecystectomy, surgical procedure data (associated procedures, intraoperative cholangiography, intraoperative complications, length of surgery, and conversion to open), and postoperative course data (postoperative morbidity, postoperative mortality, reinterventions, and postoperative hospital stay). Furthermore, biliary complications were analyzed as a single parameter comparing the incidence within groups and subgroups. Cumulative complications (intraoperative and postoperative) were also analyzed as a single parameter comparing their incidence in the series of each surgeon within the surgeon-in-training subgroup to the average results of the expert subgroup. Finally, length of surgery, postoperative complication rate, and length of postoperative hospital stay within subgroups were analyzed to evaluate the learning curve. RESULTS: Overall conversion rate was 0.87%. The mean operating time was 76.8 min (median, 70 min) in group 1 and 97.5 min (median 90 min) in group 2. BDI occurred in 1 case (0.32%) in the surgeon-in-training subgroup. Overall BDI rate was 0.22% (1/461). The overall incidence of postoperative bile leak was 2.7% (9 patients of subgroup 1 and 1 patient of subgroup 2). Clinical observation with spontaneous resolution occurred in 4 patients, and in 1 case the management consisted in an endoscopic biliary drainage; surgery was requested in the remaining cases. A laparoscopic approach was successfully attempted in all cases. Overall morbidity rate was 8.76% in group 1 and 13.84% in group 2. Rates of major complications, overall biliary complication, and postoperative bile leaks within the expert and surgeon-in-training subgroup differ significantly (p = 0.026, p = 0.03, and p = 0.049, respectively). There was 1 death (0.22%) due to sepsis that resulted from a small bowel injury by trocar insertion. Mean postoperative stay was 4.28 days for group 1 and 5.05 days for group 2. CONCLUSION: No significant difference was found in both patient groups regarding postoperative mortality and complications, biliary complications, and especially cystic duct leaks. A retrospective comparison of literature data showed that use of ultrasonic dissection during LC seems to reduce the risk of BDI. Nevertheless, a learning curve in the use of ultrasonic-activated devices is required: a significant differences in postoperative major complications and biliary complications between the expert and the surgeon-in-training subgroups was shown. Furthermore, ultrasonic scissors misuse may cause bowel injuries in patients with severe adhesions, and this could represent a possible limitation for surgical safety.

Adolescent↗
PubMed2002

Use of municipal incinerator bottom ash as sintering promoter in industrial ceramics.

The use of glassy frits obtained from municipal incinerator bottom ash and glass cullet, as sintering promoters in the production process of porcelainized stoneware, was investigated. The emphasis was on studying the similarities and differences with respect to the standard body. The characterization involved the application of several techniques: chemical analysis, X-ray powder diffraction, linear shrinkage during firing, water absorption, bending strength and spot resistance test. The results show that, the addition of these glassy frits in the body improve the characteristics of water absorption and spot resistance which is related to the absence of surface porosity originated by the glassy phase. Moreover, addition of glassy frits to the porcelanized stoneware body does not change significantly its bending strength. In the firing conditions used there is a slight worsening in the tiles planarity, while there is a significant modification of the color, which becomes darker with respect to the base body.

Ceramics↗
PubMed2000

The response of pigs inoculated with a thymidine kinase-negative (TK-) pseudorabies virus to challenge infection with virulent virus.

12 Large-White-Landrace piglets were subdivided in four groups of 3 and housed in separate units. The piglets of three groups were inoculated with the 86/27V 6C2 thymidine kinase negative (TK-) mutant of pseudorabies virus (PRV), by different routes. A second inoculation with the same mutant was given to the pigs 21 days later. The animals of a fourth group were left as uninoculated controls. 21 days following the second inoculation with the TK- mutant all pigs were challenge infected with the virulent PRV. On post challenge day (PCD) 30 all pigs were killed and samples for virus detection and histology were taken from several organs. The inoculated TK- mutant of PRV did not induce any ill effects in the pigs except a transient febrile reaction in some animals. Virus was recovered from nasal swabbings from one pig 2 days after the first inoculation of the mutant. After challenge exposure with virulent PRV, the TK- mutant-inoculated pigs were apparently protected, whereas the control pigs all were severely affected and recovered very slowly over 3 weeks. Virus was isolated from the nasal swabbings from the TK- mutant-inoculated pigs on PCDs 2 and 4, whereas the nasal swabbings from the control piglets were all positive for virus from PCD 2 through PCD 10. DNA analysis of the virus recovered showed a pattern identical to that of the virulent PRV. Histologic lesions were found in the respiratory and the central nervous systems, however, the lesions in the TK- mutant-inoculated pigs were much milder compared to those registered for the control pigs. Virus was not isolated from any of the tissue samples that were tested, but viral DNA with sequences typical of PRV genome was detected by PCR in all samples of trigeminal ganglia from either the TK- mutant-inoculated pigs or from the controls.

Administration, Intranasal↗
PubMed2000

A study of the ability of a TK-negative and gI/gE-negative pseudorabies virus (PRV) mutant inoculated by different routes to protect pigs against PRV infection.

The capacity of a TK-negative (TK-) and gI/gE-negative (gI/gE-) pseudorabies virus (PRV) mutant to protect pigs against Aujeszky's disease carried out by experimental infection with a virulent PRV strain, was tested. There were three groups, each of four susceptible pigs which were inoculated twice by two different schedules. Group 1 received the modified virus by the intradermal (first inoculation)-intramuscular (second inoculation) routes; group 2 was treated by the intranasal (first inoculation)-intramuscular (second inoculation) routes. The third group was left untreated as the control. All of the pigs were challenged intranasally with a virulent PRV strain and they were subsequently injected with dexamethasone. Two pigs in each group were necropsied on days 5 and 15 after dexamethasone inoculation. The challenge exposure resulted in mild clinical signs, increase in growth and a shorter period of virus shedding in vaccinated pigs, whereas the control group showed severe signs of Aujeszky's disease. No difference in the titre of the virulent virus which was excreted by pigs of all three groups, was observed and all animals seroconverted. Both the mutant strain and the wild-type virus established a latent infection although only the latter was reactivated and shed. Slight lesions were observed in target tissues of the vaccinated animals and no significant differences were detected between the two inoculation schedules.

Administration, Intranasal↗
PubMed1999

A computer-driven approach to PCR-based differential screening, alternative to differential display.

MOTIVATION: Polymerase chain reaction (PCR)-based RNA fingerprinting is a powerful tool for the isolation of differentially expressed genes in studies of neoplasia, differentiation or development. Arbitrarily primed RNA fingerprinting is capable of targeting coding regions of genes, as opposed to differential display techniques, which target 3' non-coding cDNA. In order to be of general use and to permit a systematic survey of differential gene expression, RNA fingerprinting has to be standardized and a number of highly efficient and selective arbitrary primers must be identified. RESULTS: We have applied a rational approach to generate a representative panel of high-efficiency oligonucleotides for RNA fingerprinting studies, which display marked affinity for coding portions of known genes and, as shown by preliminary results, of novel ones. The choice of oligonucleotides was driven by computer simulations of RNA fingerprinting reverse transcriptase (RT)-PCR experiments, performed on two custom-generated, non-redundant nucleotide databases, each containing the complete collection of deposited human or murine cDNAs. The simulation approach and experimental protocol proposed here permit the efficient isolation of coding cDNA fragments from differentially expressed genes. AVAILABILITY: Freely available on request from the authors. CONTACT: fesce.riccardo@hsr.it

Base Composition↗
PubMed1999

Experimental tracheal transplantation using a cryopreserved aortic allograft.

BACKGROUND: The tracheal reconstruction after wide resections remains a critical surgical problem. Our aim was to replace trachea with a tissue easy to vascularize, which allows a simple reconstruction and does not require an immunosuppressive regimen. MATERIALS AND METHODS: A segment of cryopreserved aorta was used in order to verify its adequacy as tracheal substitute. In phase 1, the thoracic aorta of 10 rabbits was excised, obtaining 20 segments that were cryopreserved. Ten segments were implanted in the omentum of 10 rabbits that were sacrificed on postoperative days 7, 14 and 21, and the grafts were examined histologically. In phase 2, a segment of cryopreserved aorta arranged with a silicone prosthesis was transplanted in 10 rabbits and wrapped with omentum. The animals were sacrificed on postoperative days 7, 14 and 21. RESULTS: In phase 1, the neovascularization of the grafts was present after 7 days, and after 14 days the fibroblasts invaded the lumen of the aorta. In phase 2, 8 rabbits survived and the histologic examination after 7, 14 and 21 days showed neovascularization, the absence of rejection and the proliferation of fibroblasts inside the lumen of the aorta; this growth has been restrained by an endoluminal prosthesis. CONCLUSIONS: Our study demonstrated that replacing the trachea with cryopreserved aorta is technically feasible and does not evoke immunologic reactions. It requires, however, a silicone tube inside the allograft to limit the colonization of fibroblasts.

Animals↗
PubMed1999

Preoperative plasma levels of prothrombin fragment 1 + 2 correlate with the risk of venous thrombosis after elective hip replacement.

Better preoperative identification of those patients at high risk of developing a deep vein thrombosis (DVT) after hip surgery could reduce the incidence of this postoperative complication, which still occurs despite prophylaxis. One hundred fifty-nine patients undergoing elective total hip replacement and given anticoagulant prophylaxis, were investigated, looking for the presence of a hypercoagulable state, that represents one element of Virchow's triad predisposing to DVT. Plasma levels of three markers of coagulation activation, namely prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin III complexes (TAT) and D-dimer were measured using ELISA procedures and were correlated with the results of the postoperative phlebography. A high correlation (p < 0.001) between the preoperative plasma levels of F1 + 2 and the risk of postoperative venous thromboembolism was detected. The performance of TAT and D-dimer levels in predicting DVT was lower. These findings support the hypothesis that preoperative measurement of coagulation activation markers might be useful in predicting DVT following a total hip replacement.

Adult↗