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Biomedical subjects

F Colombo

Publications and source records attributed to F Colombo.

At least 19 recordsLinked to original sources
PubMed2006

Animal model for liver cell banking from non-heart beating donors after prolonged ischaemia time.

BACKGROUND AND AIM: Although there is a growing interest on the use of non-heart beating donors to enlarge the liver donor pool, livers with prolonged warm ischaemia time are not currently considered for organ transplantation. We hypothesised that these organs may represent a source of hepatocytes for cell transplantation and/or use in bioartificial liver devices. Thus, we investigated if prolonged ischaemia could influence the recovery and viability of functional hepatocytes dissociated from rat livers. METHODS: Hepatocytes were isolated from the liver within 15 min after death (t=15 min) and after 4, 8 and 12h of ischaemia. Cells were either maintained in culture or cryopreserved. In all products, we evaluated cell recovery and viability, hepatocyte markers and cellular functions, including albumin and urea production. RESULTS: The number of cells per gram of tissue was similar at 15 min, 4 and 8h, while it was significantly decreased at 12h. About 0.2 x 10(6) viable cells expressing hepatocyte markers and producing albumin and urea were isolated up to 8h of ischaemia per gram of tissue. CONCLUSIONS: Recovery of viable and functional hepatocytes seems possible after prolonged ischaemia time. These data warrant the evaluation of hepatocyte isolation from human livers of non-heart beating donors.

Animals↗
PubMed2006

Clinical trials of gene therapy, virotherapy, and immunotherapy for malignant gliomas.

Despite advances in surgical and adjuvant therapy, the prognosis for malignant gliomas remains dismal. This gloomy scenario has been recently brightened by the increasing understanding of the genetic and biological mechanisms at the basis of brain tumor development. These findings are being translated into innovative therapeutic approaches, including gene therapy, virotherapy, and vaccination, some of which have already been experimented in clinical trials. The advantages and disadvantages of all these different therapeutic modalities for malignant gliomas will be critically discussed, providing perspective for future investigations.

Adenoviridae↗
PubMed2006

Investigation of Campylobacter in reared game birds.

A total of 103 pooled samples of neck skin and meat from pigeons for the table and neck skin of pheasant were analyzed bacteriologically to determine the presence of Campylobacter. Colonies suspected of being Campylobacter were grown from 15.8% of pigeon neck skin samples, 12.5% of pigeon meat samples, and 50% of pheasant neck skin samples after culturing, and in 6.9% of pigeon neck skin samples (4 x 10(2) to 2 x 10(3) CFU/g) assessed quantitatively without preculturing. PCR confirmed the presence of Campylobacter spp. in 5.26 and 3.44% of samples of pigeon neck skin and meat, respectively. Species identified from pigeon neck skin samples by PCR were C. jejuni (3 of 3) and C. coli (1 of 3); no C. lari was identified. No species were identified by PCR in pheasant neck skin. We conclude that the small number of Campylobacter-positive pigeon samples presents a low risk of Campylobacter infection to Italian consumers, particularly since pigeon is always well cooked before consumption, although there is always the possibility of cross-contamination with raw or insufficiently cooked foods particularly during food preparation.

Animals↗
PubMed2005

Micro-endoscopic-discectomy (MED) for far lateral disc herniation in the lumbar spine. Technical note.

This study describes a new experience of the authors in the treatment of extraforaminal disc herniation via the micro-endoscopic far lateral approach to establish a less traumatic approach to extraforaminal disc herniation with less stay in hospital and less cost. Seventeen patients who underwent surgery for extraforaminal disc herniation were analysed and long-term follow up was done revisiting all of them in hospital. The results of surgical decompression via the micro-endoscopic far lateral approach were good in all patients with minimal discomfort. There was complete resolution of leg pain presented. Dysesthesia subsided after 2-3 weeks. Extraforaminal disc herniation can be diagnosed with the aid of CT scan and MRI. The minimally invasive surgical treatment via the micro-endoscopic far lateral approach, in our initial experience, has a high rate of succes.

Diskectomy↗
PubMed2005

CT-3D rotational angiography automatic registration: a sensitivity analysis.

Preprocessing, binning and dataset subsampling are investigated with regard to simultaneous maximisation of the speed, accuracy and robustness of CT-3D rotational angiography (3DRA) registration. Clinical diagnosis and treatment can both take advantage of this integration, because 3DRA allows the shape of vessel structures to be evaluated three-dimensionally with respect to standard 2D projective angiography. The method for optimising preprocessing, binning and subsampling consisted of independent variation of the corresponding parameters to maximise robustness and speed while maintaining subvoxel accuracy; the latter was computed as the sum of the mean squared errors initially present in the registrations with the errors relative to both binning and subsampling. The results suggest the choice of 256 bins, steps between 14 mm (coarse optimisation) and 2.5 mm (fine optimisation) and bone segmentation by threshold, for binning, subsampling and preprocessing, respectively. The application of this parameter set-up to 50 CT-3DRA registrations resulted in a saving, on average, of 40% of the time with respect to the method previously used, while registration error was maintained within 2 mm (1.97 mm, 90% confidence interval) and robustness was increased, so that no manual initial realignment was needed in 48 registrations. Validation by the registration of images acquired for a head phantom showed subvoxel residual errors. In conclusion, the proposed procedure can be considered a satisfactory strategy to optimise CT-3DRA registration.

Angiography↗
PubMed2005

Long-term prognostic impact of repeated measurements over 1 year of pulse pressure and systolic blood pressure in the elderly.

Systolic blood pressure (SBP) and pulse pressure (PP) have been identified in western industrialized countries as major predictors of cardiovascular events in the elderly on the basis of measurements taken at a single visit. Considering the wide variability of blood pressure (BP) in older people, this study set out to assess the prognostic significance of measurements of SBP and PP taken over several months according to a monitoring scheme mimicking routine care. A total of 444 Italian general practitioners enrolled a cohort of 3858 unselected elderly outpatients and followed them up for 10 years. BP was recorded at recruitment, 1 week later and at quarterly visits during the first year. The average BP of these six visits was used to define the patient's BP status. During the 10-year follow-up, 1561 participants died, 709 from cardiovascular diseases. Proportional hazard regression analysis, adjusted for all main prognostic factors including antihypertensive treatment, showed that for each 10-mmHg increment in SBP and PP there were, respectively, 5 and 9% increases in risk for total mortality (TM) and 9 and 13% increases in risk for cardiovascular mortality (CVM) (all P < 0.01). However, including both SBP and PP in the model, only PP showed an independent, significant relationship with TM and CVM. In conclusion, prognostic information based on repeated measurements of PP is stronger than that given by SBP and consequently should be recommended in the definition of cardiovascular risk in the elderly.

Aged↗
PubMed2004

Cytosolic sialidase Neu2 upregulation during PC12 cells differentiation.

The cytosolic sialidase Neu2 is known to be involved in myoblast differentiation. Here, we observed a Neu2 transcriptional induction during nerve growth factor, fibroblast growth factor 2 and epidermal growth factor treatments of PC12 cells, a favored model to study neuronal differentiation. The expression analysis of Neu2 deleted promoter revealed a remarkable increase of luciferase activity in treated PC12 cells, suggesting that in this cell line the Neu2 transcriptional levels are highly regulated. The enzymatic activity of cytosolic sialidase Neu2 was found to increase transiently only during differentiation, whereas was undetectable in untreated PC12 cells. These data suggest a possible involvement of cytosolic sialidase Neu2 in differentiation of PC12 cells.

Animals↗
PubMed2004

An unusual case with relapsing neuromyelitis optica associated with undifferentiated connective tissue disease.

A case is presented with attacks of optic neuritis followed by severe myelitis 15 years later, in coincidence with a severe stressful life event. This female patient was also affected by undifferentiated connective tissue disease. This case presents some unusual and atypical findings such as: the association of a relapsing neuromyelitis optica with an undifferentiated connective tissue disease, a very long interval between optic neuritis and myelitis, and the important role of a stressful event in developing a relapse.

Female↗
PubMed2004

A preliminary trial using multi-target polymerase chain reaction (multiplex PCR) and restriction fragment length polymorphism (PCR-RFLP) on the same feedstuffs to detect tissues of animal origin.

A preliminary study using multi-target polymerase chain reaction (multiplex PCR) and restriction fragment length polymorphism (PCR-RFLP) was done on the same feedstuffs to detect animal tissues. The results of the two methods differ somewhat: PCR-RFLP did not detect any signal in any sample, but multiplex PCR detected a signal in one sample. These findings could be a basis for further investigations.

Animal Feed↗
PubMed2004

Visceral leishmaniasis complicating a connective tissue disease: three case reports from Italy.

We report the occurrence of visceral leishmaniasis in three patients coming from the northern part of Italy treated with immunosuppressive drugs for different rheumatic conditions. This paper highlights the importance of adequate work-up in those patients presenting with serious clinical manifestations that can complicate, exacerbate or mimic a systemic connective tissue disorder. A prompt diagnosis is very important because visceral leishmaniasis has a high mortality and, if untreated, can be fatal.

Adult↗
PubMed2003

Overexpression of cytosolic sialidase Neu2 induces myoblast differentiation in C2C12 cells.

Cytosolic sialidase Neu2 has been implicated in myoblast differentiation. Here we observed a significant upregulation of Neu2 expression during differentiation of murine C2C12 myoblasts. This was evidenced both as an increase in Neu2 mRNA steady-state levels and in the cytosolic sialidase enzymatic activity. To understand the biological significance of Neu2 upregulation in myoblast differentiation, C2C12 cells were stably transfected with the rat cytosolic sialidase Neu2 cDNA. Neu2 overexpressing clones were characterized by a marked decrement of cell proliferation and by the capacity to undergo spontaneous myoblast differentiation also when maintained under standard growth conditions. This was evidenced by the formation of myogenin-positive myotubes and by a significant decrease in the nuclear levels of cyclin D1 protein. No differentiation was on the contrary observed in parental and mock-transfected cells under the same experimental conditions. The results indicate that Neu2 upregulation per se is sufficient to trigger myoblast differentiation in C2C12 cells.

Animals↗
PubMed2001

Cytokine profiles in drug-naive schizophrenic patients.

A large body of evidence concerning immunological abnormalities in schizophrenic patients seems to suggest a role of the immune system in the multifactorial pathogenesis of schizophrenia. We investigated the production of various cytokines [interleukin (IL)-2, IL-4, IL-10, interferon (INF)-gamma] in drug-free (n=26) and drug-naive (n=7) schizophrenic patients and in healthy controls (n=33). Production of IL-2 and INF-gamma was significantly higher (respectively P=0.021 and P=0.001) in patients than in controls. These findings provide further evidence that immunological abnormalities are present in some schizophrenic patients.

Adult↗
PubMed2001

Computer-assisted evaluation of isoelectric focusing patterns in electrophoretic gels: identification of smoothhounds (Mustelus mustelus, Mustelus asterias) and comparison with lower value shark species.

In this work, the most commercially important Selachian species, smoothhound (Mustelus mustelus) and starry smoothhound (Mustelus asterias), have been identified by polyacrylamide isoelectric focusing (IEF-PAGE), along with several shark species of minor commercial value. In Italy, these two smoothhound species are commonly subjected to fraudulent substitution with lesser valued sharks. After the electrophoretic runs, the band patterns of the two Mustelus species were compared with those of dogfish (Scyliorhinus canicula), spurdog (Squalus acanthias), blue shark (Prionace glauca) and black-mouthed dogfish (Galeus melanostomus), both visually and with gel analysis software. The actual isoelectric points were then submitted to cluster analysis to differentiate the single species, despite the possible occurrence of electrophoretic variations or protein polymorphism. Every shark showed species-specific band patterns and could therefore be well differentiated, as confirmed by statistical analysis.

Acrylic Resins↗
PubMed2001

beta-Adrenergic stimulation of rat cardiac fibroblasts promotes protein synthesis via the activation of phosphatidylinositol 3-kinase.

beta -adrenergic agonists stimulate neonatal rat cardiac fibroblast growth, albeit the identity of the signaling event(s) remains equivocal. Isoproterenol (ISO) treatment increased intracellular cyclic AMP levels; however, cyclic AMP-elevating agents had no effect on protein synthesis. The tyrosine kinase inhibitor tyrphostin A25, and the inhibition of ras processing by the farnesyltransferase inhibitor BMS-191563 attenuated ISO-stimulated protein synthesis. Concomitant with increased protein synthesis, ISO stimulated extracellular signal-regulated protein kinase (ERK) and phosphatidylinositol 3-kinase (PI3-K) activity. The MEK1/2 inhibitor PD098059 abrogated ISO-stimulated ERK activity, albeit the increase in protein synthesis was unaffected. By contrast, LY294002 inhibited both ISO-stimulated PI3-K activity, and protein synthesis. ISO treatment did not increase the expression of transforming growth factor-beta(1)(TGF-beta(1)) mRNA, whereas a significant decrease in the steady-state mRNA level of TGF- beta(3)was observed. This latter effect was mimicked by cyclic AMP-elevating agents. Angiotensin II (AII) activation of the AT(1)receptor increased protein synthesis, but in contrast to ISO, the growth response was not inhibited by either tyrphostin A25 or BMS-191563, and was associated with the concomitant expression of both TGF-beta(1)and TGF-beta(3)mRNAs. Analogous to ISO, AII treatment increased ERK and PI3-K activity, and PI3-K was required for protein synthesis. These findings are the first to highlight the activation of PI3-K by a Gs(alpha)-coupled receptor, and its essential role in beta -adrenergic as well as AT(1)receptor-mediated protein synthesis in neonatal rat cardiac fibroblasts. However, despite the conserved role of PI3-K, additional disparate signaling pathways are recruited by ISO and AII, which may differentially influence fibroblast phenotype.

Adrenergic beta-Agonists↗
PubMed2001

Employ of a new device for intra-operative radiotherapy of intracranial tumours.

BACKGROUND: This paper presents the operating experience acquired during 18 months of use of the Photon Radiosurgery System manufactured by Photo-electron Corp. as an intra-operative radiation therapy device. The device is based on a miniature x-ray source that delivers low energy x-rays from the tip of a 3.2 mm thick needle-like probe. The interstitial stereotactic employ of the source has already been reported, while there is no evidence of the open-field intra-operative use in the literature. METHOD: Open field intra-operative radiation therapy (IORT) is possible inserting the probe into spherical applicators with diameters ranging from 1.5 to 5 cm. The applicators are made to fit the surgical cavity in order to provide uniform distance between the x-ray source and the tumour bed. Delivery of the prescribed dose takes typically 10 to 45 minutes. Radiation characteristics of the source were measured by means of ionization chambers and radiochromic films positioned in a water phantom. Operating procedures aimed at quality assurance and radiation safety were developed. IORT was administered to 14 patients affected by malignant intracranial tumours. Doses from 10 to 15 Gy at 5 mm depth from the tumour bed were delivered after tumour removal. FINDINGS: This preliminary experience does not afford any clinical evidence of IORT efficacy for intracranial lesions: it permits one however to state the feasibility and safety of the procedure. INTERPRETATION: This system could favour a rapid and significant increase of the experience of intra-operative irradiation in the treatment of CNS tumours. A role in the treatment of extracranial neoplasms can be also foreseen but needs to be more extensively investigated.

Adult↗
PubMed2001

Primary intraosseous cavernous hemangioma of the orbit.

PURPOSE: Primary orbital intraosseous hemangioma is a rare, benign neoplasm presenting most frequently in patients in their fourth or fifth decade of life. We describe an elderly patient affected by this tumor. METHODS: Case report. RESULTS: A 75-year-old man presented with a slowly growing, bony mass in the left orbital rim inferolaterally. He had a history of nephrectomy because of a renal carcinoma. Computed tomography showed a bony lesion with internal radiating trabeculations. A biopsy was performed. Histopathologically, the tumor was an intraosseous cavernous hemangioma. CONCLUSION: Primary intraosseous cavernous hemangioma of the orbit may infrequently affect elderly patients. One indication for surgical removal of these tumors in the absence of visual disturbances is to rule out metastatic disease in patients with a history of malignancy.

Aged↗