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Biomedical subjects

M Massa

Publications and source records attributed to M Massa.

At least 19 recordsLinked to original sources
PubMed2006

Laparoscopic donor nephrectomy: short learning curve.

INTRODUCTION: The learning curve of laparoscopic donor nephrectomy (LDN) may represent a great technical challenge at centers with low volume of living donors. The number of LDNs required to overcome the learning curve is still unclear. Here we report the modality of approach to LDN at a low-volume living donor transplant center. MATERIALS AND METHODS: We reviewed the records of two groups of donors operated by two different surgeons between January 2002 and October 2005. We compared donor hospital stay, operative time, presence of multiple renal arteries, blood loss, operative details, and complications. RESULTS: The first six operations (group A) were performed by a well-trained laparoscopic surgeon (A.P.) with a consolidated experience in the LDN procedure, attended by our training surgeon (R.D.V.) who conducted the other six cases (group B). No conversion to an open procedure was necessary and there were no major minor complications. Mean operative time was 267.5 (+/-55.9) minutes in group A and 300 (+/-43.4) minutes in group B (P = .28). Mean warm ischemia time was 125 (+/-61.6) seconds in group A and 189.2 (+/-18.6) seconds in group B (P = .035). Mean hospital stay was 5.3 days in group A and 5.6 days in group B. CONCLUSIONS: LDN can be performed safely and efficiently in transplant centers with initial experience. A collaborative approach to this difficult procedure with a surgeon skilled in donor nephrectomy minimizes the risk to the donor and reduces the learning curve.

Female↗
PubMed2005

Successful solitary pancreas transplantation with portal-enteric drainage following unsuccessful islet cell transplantation.

BACKGROUND: There are no data regarding the outcome of solitary pancreas transplantation (SPT) with portal venous drainage (PVD) following unsuccessful islet transplantation (ITx) after multiple islet injections into the portal vein. We herein describe the outcome of three SPTs with PVD performed after failed ITx. METHODS: Between October 2002 and December 2003, three SPTs with PVD were performed following unsuccessful ITx with multiple intraportal islet injections (mean 2.3 injections: range 2 to 3 injections) in two women and one man, aged 26, 49, and 60 years. Panel reactive antibody titer was 0% in all recipients. Immunosuppression was based on induction with either basiliximab (n = 2) or thymoglobulin (n = 1); maintenance therapy included steroids, mycophenolate mofetil, and tacrolimus. During the recipient operation, the absence of venous hypertension was established by direct measurement of portal pressure, before making the final decision to drain the pancreas into the portal vein. RESULTS: Portal pressures were 16 cm H2O, 14 cm H2O, and 13 cm H2O. Pancreas grafts were reperfused after a period of cold preservation of 638, 695, and 835 minutes, respectively. All grafts showed immediate endocrine function, maintaining their recipients insulin-independent for longest follow-ups of 8, 21, and 23 months, respectively. One recipient developed a nonocclusive venous thrombus that resolved with intravenous heparin infusion. CONCLUSIONS: Our experience showed that unsuccessful ITx with multiple intraportal injections does not necessarily preclude the possibility of subsequent successful SPT with PVD. Further experience is needed to define contraindications and possible complications of SPT with PVD following ITx.

Blood Pressure↗
PubMed2003

High circulating levels of biologically inactive IL-6/SIL-6 receptor complexes in systemic juvenile idiopathic arthritis: evidence for serum factors interfering with the binding to gp130.

We previously demonstrated that high levels of IL-6/sIL-6R complexes are present in sera of patients with systemic juvenile idiopathic arthritis (s-JIA) and that the amount of IL-6 estimated in the IL-6/sIL-6R complexes is markedly higher than that measured by the B9 assay. Here, we show that two additional bioassays, employing human myeloma XG-1 cells and human hepatoma Hep3B cells, detected serum IL-6 levels similar to those measured by the B9 assay and approximately 10-fold lower than the IL-6 levels estimated to be present in the IL-6/sIL-6R complex. Using an assay for the measurement of the amount of circulating IL-6 complexed with the sIL-6R and available for binding to gp130 (gp130 binding activity), we show that the IL-6/gp130 binding activity is similar to that detected by the bioassays and again significantly lower than that estimated to be present in the IL-6/sIL-6R complex. Addition of recombinant human IL-6 (rhIL-6) to sera of patients or controls results in a markedly lower increase in the gp130 binding activity in patients than in controls. Moreover, sera from s-JIA patients inhibited in a dose dependent manner the gp130 binding activity assay. These results show that sera from patients with s-JIA contain a factor, or factors, that inhibit(s) the binding of the IL-6/sIL-6R complex to gp130. This inhibitory activity does not appear to be due to soluble gp130, C-reactive protein or autoantibodies to IL-6.

Adolescent↗
PubMed2000

Conformational dynamics of the beta2-microglobulin C terminal in the cell-membrane-anchored major histocompatibility complex type I.

We have recently described an anti-beta2-microglobulin (beta2-m) monoclonal antibody (mAb 14H3) capable of recognizing the epitope 92-99 of the protein in the monomeric native state as well as in the fibrillar polymeric state, but not in the major histocompatibility complex type I (MHCI) anchored to the cell membrane. In the present study, we investigated the molecular basis for the inaccessibility of the C-terminal end of beta2-m in the MHCI complex, and demonstrated that mAb 14H3 binds the soluble fraction of the MHCI complex with a Kd of 0.3 microM. An interaction between the complex and the membrane protects beta2-m from immunological recognition at the MHCI level. This protection from antibody recognition can be weakened by procedures such as heat shock or gamma irradiation that perturb the membrane structure and commit the cell to the apoptotic pathway. mAb 14H3 can recognize MHCI in a transient state that most likely precedes beta2-m shedding and may be proposed as a useful tool for dynamic analysis of MHCI conformational modifications.

Antibodies, Monoclonal↗
PubMed2000

Circulating levels of soluble E-selectin, P-selectin and intercellular adhesion molecule-1 in patients with juvenile idiopathic arthritis.

OBJECTIVE: To measure circulating levels of soluble E-selectin (sE-selectin), sP-selectin, and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with active juvenile idiopathic arthritides (JIA), and to evaluate their correlation with disease activity variables and cytokine levels. METHODS: Serum levels of sE-selectin, sP-selectin, and sICAM-1 were measured by ELISA in 42 patients with JIA and in 15 healthy controls. RESULTS: Circulating levels of sE-selectin and sICAM-1, but not sP-selectin, were significantly elevated in patients with active systemic JIA. In patients with active polyarticular or pauciarticular JIA serum levels of sE-selectin. sP-selectin, and sICAM-1 were comparable to those of controls. In patients with systemic JIA, levels of sE-selectin and sICAM-1 were significantly correlated with levels of soluble tumor necrosis factor receptor 2 (sTNFR2), but not with those of interleukin 6 (IL-6) or IL-1beta. CONCLUSION: Patients with active systemic JIA have elevated circulating levels of sE-selectin and sICAM-1. The correlation with sTNFR2, together with previous data on the TNF system in systemic JIA. suggests that TNF activated endothelial cells are the source of sE-selectin and sICAM-1 in this disease.

Adolescent↗
PubMed1998

p53 exon 7 mutations as a predictor of poor prognosis in patients with colorectal cancer.

We have studied 61 resected colorectal adenocarcinomas in order to investigate p53 mutations as a prognostic factor for this pathology. Mutations in exons 5-9 of the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique followed by sequencing. Our data indicate that p53 exon 7 mutations were prevalent in the latest stages of colorectal carcinogenesis and patients bearing this alteration had the worst prognosis. Therefore, according to our results, mutations affecting exon 7 of the p53 gene could be considered as a useful marker of biological aggressiveness for colorectal cancer.

Aged↗
PubMed1997

Soluble tumour necrosis factor receptor levels reflect coagulation abnormalities in systemic juvenile chronic arthritis.

The objective was to evaluate tumour necrosis factor (TNF) status in patients with systemic juvenile chronic arthritis (s-JCA). Plasma levels of TNF-alpha, and serum levels of soluble TNF receptor 1 and 2 (sTNFR1 and sTNFR2) were measured using specific immunoassays in 20 patients with s-JCA, 10 with polyarticular JCA and 15 with pauciarticular JCA, and in 20 controls comparable for age. In patients with active s-JCA, circulating levels of TNF-alpha, sTNFR1 and sTNFR2 were significantly (P < 0.001) higher than those of controls. The levels of sTNFR1 and sTNFR2, but not those of TNF-alpha, were associated with the persistence and severity of systemic symptoms and were significantly correlated with prolongation of partial thromboplastin time and decrease in prothrombin activity. In two patients evaluated during a s-JCA-associated macrophage activation syndrome, a marked increase in sTNFR1 and sTNFR2 was found. Our results suggest that in s-JCA, TNF is involved in systemic manifestations, in the subclinical coagulation abnormalities, and in the development of the macrophage activation syndrome.

Adolescent↗
PubMed1997

Differences in synovial fluid cytokine levels between juvenile and adult rheumatoid arthritis.

OBJECTIVE: To evaluate quantitative or qualitative differences in synovial fluid (SF) cytokine levels among patients with systemic juvenile rheumatoid arthritis (JRA), antinuclear antibody positive pauciarticular JRA, or adult RA. METHODS: SF levels of interleukin 1alpha (IL-1alpha), IL-1beta, IL-1 receptor antagonist (IL-1Ra) IL-11, tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptor 1 (sTNFR1), leukemia inhibitory factor (LIF), all measured by immunoassays, and of IL-6, measured with a bioassay using B9 cells, were evaluated in 11 patients with systemic JRA, 24 with pauciarticular JRA, and 22 adult patients with RA. RESULTS: SF IL-6 levels were significantly higher in patients with systemic JRA than patients with pauciarticular JRA (p = 0.003) or RA (p = 0.002). IL-1alpha was detectable in 12/24 SF samples from pauciarticular JRA, in 2/22 SF from RA, and in no sample from systemic JRA (p = 0.004 vs RA; p = 0.005 vs systemic JRA). SF IL-11 levels were significantly higher in patients with RA than patients with systemic JRA (p = 0.012) or pauciarticular JRA (p = 0.005). We found no significant differences in SF levels of IL-1beta, IL-1Ra, TNF-alpha, sTNFR1, or LIF. CONCLUSION: In systemic JRA, SF levels of IL-6 are significantly higher than in pauciarticular JRA or in RA; IL-1alpha is present in a significant proportion of patients with pauciarticular JRA, but not in those with RA or systemic JRA.

Adolescent↗
PubMed1997

Membrane CD22 defines circulating myeloma-related cells as mature or later B cells.

Circulating clonally related earlier cells are present in multiple myeloma (MM) and may be involved in the dissemination of this disease, its recurrence, and chemoresistance. The nature, stage of differentiation, and size of this cell population remain uncertain. Unlike other B-cell markers, CD22 membrane expression is limited to the late differentiation stages comprised between mature B cells (CD22+) and plasma cells (PC; CD22-) and may thus be useful in delimiting the maturational state of circulating early myeloma cells. Peripheral blood clone-related cells were detected by anti-idiotypic (Id) monoclonal antibodies and found to express CD22 (92% to 95%), monotypic light and heavy chain (100%), and CD38 (45%), whereas bone marrow PC were CD22-negative. CD22 expression was also documented on functional myeloma PC precursors, defined as peripheral blood cells capable of in vitro cytokine-driven monotypic PC differentiation, because up to approximately 70% inhibition of this process was obtained in 10 myeloma patients through the use of biospecific antibodies (BsAb) that deliver the plant toxin saporin to CD22+ cells. As further evidence of CD22 on circulating abnormal cells, it was found that in the only patient analyzed for DNA content, a portion of the peripheral blood CD22+ cells killed were hyperdiploid. Collectively, these findings indicate that most peripheral blood myeloma PC precursors are mature or later B cells presenting membrane CD22. The pattern of CD22 expression suggests the existence in MM of a differentiation process analogous to the normal antigenic response, in which CD22+ B cells migrate to the bone marrow and lose CD22 with PC differentiation. In addition, the sensitivity of myeloma PC precursors to the cytotoxic effects of the anti-CD22 BsAb and the possibility of interfering with their differentiation have potential therapeutic relevance.

Amyloidosis↗
PubMed1996

The AGROBOT project.

The aim of this paper is to illustrate the AGROBOT project. This project was initiated to develop a complete robotic system for the production cycle of tomato plants in a greenhouse environment. The robot architecture is based on a vehicle carrying the picking arm (a six degrees of freedom anthropomorphic arm with a gripper/hand), the head with the two micro cameras (for the color stereoscopic vision system) and the VME rack for the complete control of the system. The head was purposely developed to permit complete visibility of the overall area. The vision system drives the head to point the path during navigation or to explore the plants looking for the work objects. The robot will be able to navigate between rows of plants, stop near each plant and identify the relevant objects (fruits or flowers) so as to be able to pick ripe tomatoes or spray anticryptogamic substances on flowers. Due to its flexible architecture, the system can be suited to operate on other kinds of cultivation or could be modified to perform other kinds of operations such as transplanting or packaging. Also the field of action could be different from greenhouses: changing from a wheeled locomotion system to a tracked system, the robot will be able to operate on particularly irregular surfaces. These features make this robotic system particularly adapted to replace human from tiring and harmful tasks or operating within adverse environment.

Agriculture↗
PubMed1996

Clinical strain of Staphylococcus aureus inactivates and causes efflux of macrolides.

Searching through a collection of 124 Staphylococcus aureus clinical strains, we found one isolate, strain 01A1032, that inactivates 14- and 16-membered macrolides. The products of inactivation were purified from supernatant fluids of cultures exposed to erythromycin for 3 h and were found to be identical to products of inactivation from Escherichia coli strains that encode either an EreA or EreB esterase. Further, strain 01A1032 was shown to be resistant to azithromycin, a 15-membered macrolide, by an alternate mechanism, efflux. Thus, strain 01A1032 harbors determinants encoding an esterase activity that hydrolyzes 14- and 16-membered macrolides and a macrolide efflux system.

Anti-Bacterial Agents↗
PubMed1995

Lack of temporal association of iridocyclitis with IgG reactivities to core histones and nucleosome subparticles in pauciarticular juvenile chronic arthritis.

This study aimed to measure IgG reactivities to DNA-free nucleosome subparticles (H2AH2B, H3H4) and nucleosome subparticles (H2AH2B-DNA, H3H4-DNA) and to evaluate the temporal relation of these reactivities, as well as those to single core histones, with iridocyclitis (IC) in patients with antinuclear antibody positive (ANA+) pauciarticular juvenile chronic arthritis (JCA). Reactivities to nuclear substrates were determined by enzymatic immunoassays in 120 sera from 45 children with ANA+ pauciarticular JCA. Significantly elevated IgG levels to H3 and H4, to DNA-free nucleosome subparticles, and to the nucleosome subparticle H3H4-DNA were present in patients with ANA+ pauciarticular JCA; no evidence of recognition of conformational epitopes was found. In both horizontal and follow-up studies, no relation between the reactivities studied and the development, presence, or history of IC was found. Our results show the absence of a relation of antibodies to histone molecules or to nucleosome subparticles with IC in patients with ANA+ pauciarticular JCA.

Adolescent↗
PubMed1995

Circulating levels of interleukin-6, interleukin-8, and tumor necrosis factor-alpha in children with autoimmune hepatitis.

Circulating levels of the proinflammatory cytokines interleukin-6 (IL-6), IL-8, and tumor necrosis factor-alpha (TNF-alpha) were measured in 13 children with autoimmune hepatitis (AIH) (seven with type 1 and six with type 2). In untreated children with type 1 AIH, TNF-alpha, IL-6, and IL-8 levels were elevated when compared to those of healthy controls (p < 0.005, p < 0.02, p = 0.06, respectively), whereas in children with type 2 AIH, cytokine levels were normal in all except one sample. A significant decrease in circulating IL-6, IL-8, and TNF-alpha was observed when patients were evaluated during a subsequent remission. We found no significant correlation of cytokine levels with alanine aminotransferase (ALT) activity, total serum gamma-globulins, or prothrombin activity. In patients with cirrhosis, serum IL-8 and IL-6 levels were higher (significantly in the case of IL-8) than those of patients without cirrhosis. In conclusion, activation of the in vivo production of the proinflammatory cytokines IL-6, IL-8, and TNF-alpha appears to be associated with type 1 but not with type 2 AIH.

Adolescent↗
PubMed1995

Elevated circulating interleukin-7 levels in patients with systemic juvenile rheumatoid arthritis.

OBJECTIVE: Since interleukin-7 (IL-7) has been shown to induce monocyte production of IL-1, IL-6, IL-8, and tumor necrosis factor-alpha, we investigated plasma and synovial fluid levels of IL-7 in patients with juvenile rheumatoid arthritis (JRA). METHODS: IL-7 levels were measured using an ELISA in 60 patients with JRA and in 25 patients with other rheumatic disorders (ORD). RESULTS: In patients with systemic JRA, but not in patients with polyarticular or pauciarticular JRA or with ORD, plasma IL-7 levels were significantly higher (p < 0.0001) than those of healthy controls. IL-7 was undetected in all synovial fluid tested. Among patients with systemic JRA, those with persistent systemic symptoms had IL-7 levels significantly higher (p < 0.01) than those of patients in which systemic symptoms subsided. CONCLUSION: Plasma IL-7 levels are elevated in patients with systemic JRA and are associated with the presence and severity of systemic symptoms.

Adolescent↗
PubMed1995

[Complications of elective hepatic resections. Analysis of risk factors].

In the last decades the hepatic surgery has been more and more employed thanks to improvement of the surgical technique and of the post-operative assistance which have brought the peroperative mortality of principal specialistic centres to less of 5%. The main post-operative complications which trouble the hepatic surgery, forming in same cases the cause of the death, are: hepatic insufficiency, haemorrhage, subphrenic abscess and the appearance of biliary fistulas. These complications are often connected and linked to the devitalization of a part of the residual parenchyma. We have made a retrospective study on a series of 214 hepatic resections, executed in election, to estimate the main pre and intra-operative risk factors. The operative mortality has been zero whereas the post-operative one is occurred in 4.2% of the cases with a morbidity of 27.5%. In our experience the meaning full factors to prefigure an operative risk are resulted: the associated pathologies like diabetes, cardiopathies, ipertension and bronchopathies; the length of the operation; the entity of the peroperative haematic loss and of the consequent transfusional therapy and eventually quality the residual parenchyma.

Adolescent↗
PubMed1994

Hypocomplementemic urticarial vasculitis syndrome with severe systemic manifestations.

We describe two children with clinical and laboratory features of hypocomplementemic urticarial vasculitis syndrome. Both patients had severe, life-threatening manifestations: rapidly progressive glomerulonephritis (patient 1) and pulmonary hemorrhage (patient 2). We conclude that this syndrome may be a potentially severe multisystem disease.

Adolescent↗