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F Mosca

Publications and source records attributed to F Mosca.

At least 19 recordsLinked to original sources
PubMed2002

Grasping and dissecting instrument for hand-assisted laparoscopic surgery: development and early clinical experience.

BACKGROUND: The operative potential of hand-assisted laparoscopic surgery (HALS) could be enhanced by the introduction of a new generation of assisting instruments. These tools will have to meet specific requirements of shape, function, and safety of use. METHODS: Problems related to the working environment of HALS and deriving projectual restrictions of HALS instruments were analyzed in order to develop and manufacture a working prototype with grasping and dissecting properties to assist during HALS procedures. The resulting instrument was mechanically and clinically tested in 22 HALS procedures. RESULTS: The additional benefit of the new device was particularly appreciated during dissection and isolation of vascular pedicles (nephrectomies and splenectomies). It was shown to be safe and effective in providing the additional assistance it was designed for. CONCLUSION: The described grasping and dissecting instrument for HALS is of great value in assisting the surgeon during fine dissection, as required in selected procedures. New generation of HALS instruments should comply with the functional and safety issues analyzed in this report.

Equipment Design↗
PubMed2002

Inhibition of mycophenolic acid glucuronidation by niflumic acid in human liver microsomes.

OBJECTIVES: The first aim of this investigation was to study the variability of mycophenolic acid (MPA) glucuronidation rate in human liver. The second aim was to study the inhibition type of niflumic acid (NA) for MPA glucuronidation in human liver. The third aim was to study the variability of the IC(50) value of NA for MPA glucuronidation in human liver. METHODS: The rate of MPA glucuronidation was measured by employing an assay based on uridine 5'-diphosphate-[U-(14)C]-glucuronic acid (UDPGA), and MPA glucuronide was isolated by means of thin-layer chromatography. The necessary concentration for UDPGA and MPA was 1 mM. The rate of MPA glucuronidation was measured in 50 human liver samples. The inhibition type of NA for MPA glucuronidation was studied in 5 human liver samples. The NA IC(50) value was measured in 27 human liver samples using six concentrations of NA ranging from 1.05 microM to 34 microM. RESULTS: MPA glucuronidation rate was positively skewed, was not gender regulated and did not correlate with the liver donor's age. The rate of MPA glucuronidation varied 4.8-fold within the 5th and 95th percentiles, with a mean+/-SD and a median of 2.8+/-1.0 nmol/min/mg and 2.5 nmol/min/mg, respectively. The inhibition type of NA for MPA glucuronidation was mixed non-competitive. The Ki value of NA (mean+/-SD) was 15+/-10 microM and, in non-inhibited samples, the K(m) value for MPA was 0.41+/-0.06 mM. The distribution of NA IC(50) value varied 3.3-fold within the 5th and 95th percentiles with a mean+/-SD and a median of 5.6+/-2.1 microM and 5.2 microM, respectively. The distribution of NA IC(50) value did not deviate significantly from normality. CONCLUSION: The range of hepatic rate of MPA glucuronidation is narrow relative to those of ethinyloestradiol, testosterone and zidovudine glucuronidation obtained from literature. The Ki value of NA is one order of magnitude lower than the K(m) for MPA in non-inhibited samples. This indicates that the inhibitor affinity for glucuronosyl transferase is greater than that of the substrate. The range of variation of NA IC(50) values is narrow.

Adult↗
PubMed2002

Coenzyme Q10 levels in idiopathic and varicocele-associated asthenozoospermia.

Levels of coenzyme Q10 (CoQ10) and of its reduced and oxidized forms (ubiquinol, QH2, and ubiquinone, Qox) have been determined in sperm cells and seminal plasma of idiopathic (IDA) and varicocele-associated (VARA) asthenozoospermic patients and of controls. The results have shown significantly lower levels of coenzyme Q10 and of its reduced form, QH2, in semen samples from patients with asthenospermia; furthermore, the coenzyme Q10 content was mainly associated with spermatozoa. Interestingly, sperm cells from IDA patients exhibited significantly lower levels of CoQ10 and QH2 when compared to VARA ones. The QH2/Qox ratio was significantly lower in sperm cells from IDA patients and in seminal plasma from IDA and VARA patients when compared with the control group. The present data suggest that the QH2/Qox ratio may be an index of oxidative stress and its reduction, a risk factor for semen quality. Therefore, the present data could suggest that sperm cells, characterized by low motility and abnormal morphology, have low levels of coenzyme Q10. As a consequence, they could be less capable in dealing with oxidative stress which could lead to a reduced QH2/Qox ratio. Furthermore, the significantly lower levels of CoQ10 and QH2 levels in sperm cells from IDA patients, when compared to VARA ones, enable us to hypothesize a pathogenetic role of antioxidant impairment, at least as a cofactor, in idiopathic forms of asthenozoospermia.

Coenzymes↗
PubMed2001

Hand-assisted laparoscopic low anterior resection: initial experience with a new procedure.

BACKGROUND: Laparoscopic low anterior resection for rectal cancer has never gained wide acceptance among general surgeons, mainly due to the technical difficulties encountered during pelvic dissection. It has therefore been stated that these patients should undergo open rather than laparoscopic surgery. Hand-assisted laparoscopic surgery (HALS) is a new technique that has the potential to overcome many of the existing limitations of pure laparoscopy. In the treatment of rectal cancer, HALS could reproduce an operative setting similar to that of the open approach. METHODS: To assess the technical feasibility of hand-assisted laparoscopic low anterior resection for rectal cancer and evaluate potential benefits and drawbacks of this new procedure, a pilot study was conducted at a university hospital on 16 consecutive patients during a 12-month period. Only patients with extraperitoneal rectal cancer were included in this series. Patients' clinical data, operative time, conversion rate, complications, and early outcome measures were prospectively examined. RESULTS: There were 9 men and 7 women. The average +/- SD operation time was 238 +/- 38 min. Conversion to open surgery was never required. Ten of 16 patients were off pain medication on the third postoperative day. Eight were able to walk the day after surgery. Three minor postoperative complications were recorded. Mean postoperative stay for patients without complications was 5.6 +/- 1.4 days. CONCLUSION: From a technical standpoint, the reported hand-assisted procedure makes pelvic dissection during laparoscopic low anterior resection almost equivalent to the laparotomic operation. The incision for hand access that is needed with this technique does not seem to compromise the quick recovery of patients undergoing purely laparoscopic procedures.

Aged↗
PubMed2001

Kidney preservation with university of Wisconsin and Celsior solution: a prospective multicenter randomized study.

BACKGROUND: Although the University of Wisconsin (U.W.) solution continues to be the most commonly used for intra-abdominal organs, a new solution, Celsior, already used for heart and lungs, has been proposed for kidney and liver preservation. The aim of this research was to assess the effect of Celsior as compared with U.W. on immediate graft function and a 2-year follow-up of kidney transplants. METHODS: A prospective multicenter randomized study was designed to evaluate the efficacy of the Celsior solution in the clinical preservation of the kidney. In this report, we present the data collected as of September 2000. One hundred donors were included in the trial resulting in 187 renal transplants. Ninety-nine kidneys were stored in Celsior solution and 88 in U.W. solution. The groups were comparable with regard to donor and recipient characteristics. RESULTS: Delayed graft function occurred in 31.3% of the Celsior group and in 33.9% of the U.W. group (P=n.s.). Mean serum creatinine levels and mean daily urinary output were also comparable. Two year graft survival in kidneys preserved with Celsior was 84% as compared with 75% for U.W.-preserved kidneys without any significant statistical difference. CONCLUSIONS: Our data show that the preservation of kidneys in Celsior solution in a clinical setting is equivalent to that of U.W. solution. When using Celsior during multiple-organ donor harvesting it would be possible to perform an in situ flush of all intra-abdominal and intrathoracic organs with a single cold storage solution.

Adenosine↗
PubMed2001

Inhibition of protein farnesylation enhances the chemotherapeutic efficacy of the novel geranylgeranyltransferase inhibitor BAL9611 in human colon cancer cells.

Proteins belonging to the ras superfamily are involved in cell proliferation of normal and neoplastic tissues. To be biologically active, they require post-translational isoprenylation by farnesyl-transferase and geranylgeranyl-transferase. Enzyme inhibition by drugs may thus represent a promising approach to the treatment of cancer. Therefore, the combined effect of BAL9611, a novel inhibitor of geranylgeranylation, and manumycin, a farnesyl-transferase inhibitor, was evaluated on the SW620 human colon cancer cell line which harbours a mutated K-ras gene. BAL9611 and manumycin dose-dependently inhibited SW620 cell growth with 50% inhibitory concentration (IC(50)) of 0.47 +/- 0.03 and 5.24 +/- 1.41 microM (mean +/- SE), respectively. The isobologram analysis performed at the IC(50)level revealed that the combined treatment was highly synergistic with respect to cell growth inhibition. BAL9611 and manumycin were able to inhibit the geranylgeranylation of p21rhoA and farnesylation of p21ras; both drugs inhibited p42ERK2/MAPK phosphorylation, but their combination was more effective than either drug alone. Moreover, the enhanced inhibition of cell growth in vitro by the BAL9611-manumycin combination was also observed in vivo in CD nu/nu female mice xenografted with SW620 tumours. Finally, both drugs were able to induce cell death by apoptosis in vitro and in vivo, as demonstrated by perinuclear chromatin condensation, cytoplasm budding and nuclear fragmentation, and interoligonucleosomal DNA digestion. In conclusion, the inhibition of protein farnesylation enhances the chemotherapeutic effect of BAL9611 in vitro and in vivo in a synergistic fashion, as a result of the impairment of post-translational isoprenylation of proteins and phosphorylation of p42ERK2/MAPK, whose activation is associated with post-translational geranylgeranylation and farnesylation of p21rhoA and p21ras.

Alkyl and Aryl Transferases↗
PubMed2001

Bcl-2 expression in pancreas development and pancreatic cancer progression.

Apoptosis is important for both tissue development and differentiation; its deregulation may contribute to tumourigenesis. In order to clarify the role of Bcl-2, an apoptosis-inhibiting protein, in pancreatic morphogenesis and tumour progression, its immunohistochemical expression was evaluated in 12 samples of fetal pancreas, in 10 samples of adult pancreas with ductal hyperplastic lesions, in 120 cases of primary pancreatic ductal adenocarcinoma, and in 43 synchronous metastatic lymph nodes. To evaluate the role of apoptosis in pancreatic cancer, p53 expression was also studied in tumour samples. Bcl-2 cytoplasmic acinar and ductal immunostaining was found in all fetal and adult tissue samples; ductal hyperplastic lesions were constantly negative. Thirty out of 120 (25%) tumours and 3 out of 43 (7%) lymph nodes expressed Bcl-2, whereas 67 out of 120 (56%) expressed nuclear p53. Well-differentiated tumours (G1) were more frequently Bcl-2-positive (p=0.002); furthermore, there was an inverse correlation between Bcl-2 and p53 expression in primary tumours (p=0.02). Neither Bcl-2 nor p53 influenced patients' prognosis, which was instead affected by N (p=0.02) and M (p<0.0001) status and stage of the disease (p=0.002). It is concluded that Bcl-2 regulates pancreatic morphogenesis and tissue homeostasis from early fetal to adult life and can be considered a phenotypic marker of normal exocrine pancreas. On the other hand, the lack of expression in preneoplastic lesions and the low positivity found in primary tumours and lymph node metastases suggest that Bcl-2 does not play a centralrole in pancreatic tumourigenesis and cancer progression.

Adenocarcinoma↗
PubMed2001

Surgical endarterectomy for suprarenal iliac artery stenosis in renal allograft recipient.

Aortoiliac surgery performed in renal transplant recipients carries the risk of inducing a prolonged period of ischemia that can threaten organ survival. Recently, endovascular techniques have been increasingly applied but the rate of complications and recurrences remains significant. We report the case of a kidney heterotopic allotransplant recipient who presented with a history of new-onset arterial hypertension, right lower limb claudication, and allograft dysfunction related to a long, eccentric, and ulcerated plaque causing hemodynamic stenosis of suprarenal iliac artery that was successfully managed with surgical endarterectomy. Despite new advances in less invasive procedures such as transluminal angioplasty and stent implantation, surgical endarterectomy of suprarenal iliac artery may be safely performed in selected heterotopic kidney transplant recipients. It allows for complete removal of the plaque, with better long-term results, and does not preclude subsequent endovascular or surgical procedures; therefore it should be considered a therapeutic option in this clinical setting.

Arterial Occlusive Diseases↗
PubMed2001

Detection of biliary complications after orthotopic liver transplantation with MR cholangiography.

To assess the diagnostic value of magnetic resonance cholangiography (MRC) when evaluating biliary complications in the follow-up of liver transplant patients. One hundred and thirteen patients prospectively underwent MR imaging and MR cholangiography at 1.5-T unit after orthotopic liver transplantation (OLT). After the acquisition of axial T1- and T2-weighted sequences, MRC involved a coronal, non breath-hold, respiratory-triggered, fat-suppressed, two-dimensional, thin-slab, heavily T2-weighted fast spin-echo sequence, and coronal breath-hold, thick-slab, single-shot T2-weighted sequences. The images and maximum intensity projections were evaluated by two readers in order to determine biliary anatomy and the presence of complications, whose final diagnosis was based on endoscopic retrograde cholangiography (ERC) in 50 patients, percutaneous trans-hepatic cholangiography (PTC) in five, and by integrating clinical follow-up with ultrasound and MR findings in 58 cases. MRC had a sensitivity of 93%, a specificity of 92%, a positive predictive value of 86%, a negative predictive value of 96%, and a global diagnostic accuracy of 93% in detecting all types of biliary complications in OLT patients. MRC is a reliable technique for detecting post-OLT biliary complications. We now restrict the use of ERC to patients for whom therapeutic procedures are advocated or whose MRC results are equivocal.

Adult↗
PubMed2001

Modulation of beta2 integrin phenotype, adhesion, chemotaxis, and oxidative burst of neutrophils by cyclosporine.

Cyclosporine (CsA) is an immunosuppressive drug widely used to prevent allograft rejection, but its action on neutrophil function is not well known. Neutrophils play an important role in tissue damage during allograft rejection; chemotactic recruitment, adhesion to endothelial cells and oxidative burst of neutrophils are early events during allograft rejection. The aim of this work was to evaluate the effect of CsA on beta2 integrins' surface expression, adhesion to human umbilical endothelial cells (HUVECs), chemotaxis and oxidative burst by neutrophils. For any neutrophil function studied, data obtained from activated neutrophils exposed to CsA were compared with those derived from untreated controls. Results show that CsA does not block neutrophil chemotaxis and does not reduce surface expression of CD11 complex and HUVECs' adhesion at all concentrations tested (15, 100 and 500 ng/mL) and at incubation times of 1, 2 and 4 h as compared to controls. On the other hand, the drug affects significantly the CD18 phenotype after two hours of treatment at the maximum concentration (500 ng/mL) (P < 0.05; ANOVA) and the oxidative burst after four hours (P < 0.01; ANOVA). This study provides evidence that in addition to the well-known CsA effects on lymphocyte functions, the drug affects some neutrophil functions with dose- and time-dependent modalities.

Antibodies, Monoclonal↗
PubMed2001

Animal models of fulminant hepatic failure: need to test liver support devices.

Fulminant hepatic failure is one of the most dramatic entities in clinical medicine, but experimental studies of its pathogenesis, evolution and treatment have, so far been limited by the lack of satisfactory animal models for testing new supportive treatment options. The variable aetiology, complex pathogenetic mechanisms and inconstant clinical evolution of human fulminant hepatic failure make it particularly difficult to establish an "ideal fulminant hepatic failure animal model" suitable for all studies: it is no longer mandatory to develop one single model serving all possible scientific needs, but the use of a specific model for a specific issue is more advisable. The currently available animal models of fulminant hepatic failure are the hepatotoxic, surgical and combined hepatotoxic and surgical models. From a general point of view, surgical models may be particularly appropriate for studying the consequences of hepatic necrosis on cerebral oedema. The anhepatic model is very useful for validating new supportive measures to bridge the period between the onset of fulminant hepatic failure and the time at which a suitable organ becomes available and, despite the many difficulties involved in their development, hepatotoxic models may still be useful for mimicking an acetaminophen overdose. The efficacy and reproducibility of a liver support system can be demonstrated by means of preclinical experimental models that mimic the specific application required in humans as closely as possible.

Acetaminophen↗
PubMed2001

Cryptic subtelomeric translocation t(2;16)(q37;q24) segregating in a family with unexplained stillbirths and a dysmorphic, slightly retarded child.

We here describe a submicroscopic translocation affecting the subtelomeric regions of chromosomes 2q and 16q, and segregating in a family with stillbirths, early pregnancy losses, and two dysmorphic and slightly retarded babies. FISH analysis showed a 46,XY,der(2)t(2;16)(q37.3;q24.3) in the propositus, and a balanced t(2;16) in his mother, her conceptus and maternal grandfather. FISH with YACs and BACs made it possible to map the 2q37 breakpoint precisely between the regions covered by y952E1 and y746H1, and the 16q breakpoint between the regions encompassed by bA 309g16 and bA 533d19. The contribution of 2q37.3 monosomy and 16q24.3 trisomy to the proband's phenotype is compared with that in reported patients with similar imbalances of either chromosome.

Chromosomes, Human, Pair 16↗
PubMed2001

Very early tracheal extubation without predetermined criteria in a liver transplant recipient population.

This study of all patients undergoing orthotopic liver transplantation (OLT) at our center between January 1997 and December 1999 evaluated the feasibility and safety of very early tracheal extubation without previous selection. Anesthetic management was the same in all cases, and tracheal extubation was performed on the basis of standardized criteria routinely adopted in operating rooms throughout the world, i.e., no residual curarization or anesthetic action, ability to swallow efficiently, and stable hemodynamics. One hundred sixty-nine patients underwent 181 OLTs during the study period. Tracheal extubation was performed within 3 hours of surgery in 115 cases, 8 hours in 19 cases, and 8 to 24 hours in 10 cases. In 36 cases, artificial ventilation was required for more than 24 hours or weaning was not possible. One patient died of primary graft nonfunction within 24 hours and was excluded from the analysis. The feasibility of early extubation was influenced by the amount of intraoperative transfused blood; efficacy of kidney, cardiac, and pulmonary function; and presence of encephalopathy (P <.001). No correlation was found with age or pre-OLT severity of hepatic disease, and the postoperative period was not compromised by early weaning. Very early extubation was feasible and safe in a large number of unselected transplant recipients, thus suggesting that the definition of early tracheal extubation should be changed from 8 to 3 hours after surgery.

Adult↗