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P Bruno

Publications and source records attributed to P Bruno.

At least 37 records · Page 2Linked to original sources
PubMed2001

Aortic root remodeling with the "cuff" technique for stentless valve implantation.

Aortic root and sinotubular junction dilatation and aneurysm of ascending aorta are considered relative contra-indications to implantation of a stentless valve prosthesis, because the modified aortic geometry leads to aortic incompetence and early failure of the prosthesis. Aortic root reconstruction can be performed according to various techniques. We present a surgical technique in which a tubular graft, replacing an ascending aortic aneurysm, allows sinotubular remodeling and satisfactory implantation of a stentless prosthesis. The native aorta is inserted into the vascular prosthesis at the level of the sinotubular junction which is wrapped in order to prevent commissure spreading. Sizing of the vascular and valve prosthesis is made according to annular diameter. Since October 1999, 6 patients have been operated using this technique with good results.

Aortic Aneurysm, Thoracic↗
PubMed2001

An immunofluorescence technique for staining ciliated protozoans: highlighting cytoplasmic microtubular arrays and stages of micronuclear meiosis.

Ciliated protozoans represent useful organisms for studying the processes involved in the induction and progression of meiosis. In this short report we describe a technique that has allowed us to examine different meiosis phases during the sexual reproduction of Blepharisma japonicum. In order to visualize the phases of meiosis, sexually reproducing pairs were stained by an enhanced technique of anti-tubuline indirect immunofluorescence. Meiotic micronuclei, particularly those showing metaphase spindles, were clearly highlighted. The technique also heavily decorates the main microtubular cytoplasmic arrays in Blepharisma.

Animals↗
PubMed2001

Catastrophic consequences of a free floating thrombus in ascending aorta.

Floating masses in ascending aorta are an uncommon source of embolism. We report the case of a 46-year-old woman, smoker, on synthetic progestagen, with no previous history of thrombotic events, who was admitted to our emergency department for an acute anterior myocardial infarction. Coronary angiogram showed occlusion of left main coronary trunk. Recanalization of the artery was obtained. Ascending aorta angiogram revealed a free floating mass attached to the aortic wall without evidence of aortic dissection. Transesophageal echocardiography confirmed the presence of a pedunculated mobile mass attached to the aortic wall superior to the left coronary ostium. The patient underwent urgent surgery. Intraoperatively a floating thrombus was localized in the posterior wall of ascending aorta. At macroscopical examination aortic wall and leaflets were normal. Post-operative low cardiac output refractory to inotropic drugs and intraaortic balloon counterpulsation required a circulatory assist device. Consequences for the patient were catastrophic in terms of outcome.

Aorta↗
PubMed2001

Associations of PKC isoforms with the cytoskeleton of B16F10 melanoma cells.

Although PKC plays a major role in regulating the morphology and function of the cytoskeleton, little is known about in situ associations of specific isoforms with the cytoskeleton. We demonstrate that seven PKC isoforms are expressed in B16F10 melanoma cells and show different levels of induction by serum. Using cell cytoskeleton preparations (CSKs), confocal microscopy, and immunocytochemistry, all isoforms show specific patterns of localization to focal contact-like structures (alpha, delta), very small cytoplasmic granules/vesicles (all isoforms), dense ordered arrays of small granules in the perinuclear region (alpha, delta), granules/vesicles associated with a homogeneous framework in the cytoplasm adjacent to the nucleus (gamma), or irregular-shaped patches of granules at or near the nuclear perimeter (eta, theta). In addition, several isoforms are present as cytoplasmic granules/ vesicles in linear or curvilinear arrays (alpha, delta, epsilon, theta). When isoform localization is examined using 3.7% formaldehyde or methanol:acetone, the patterns of localization in CSKs are often difficult or impossible to detect, and many are described here for the first time. Double-labeling experiments with CSK demonstrate that PKC actin co-localizes with punctate alpha-rich particles above the nucleus, granules of epsilon throughout the cytoplasm, and with theta in irregular-shaped aggregates associated with the nucleus. Vimentin co-localizes with perinuclear granules of delta and beta(2), and alpha-tubulin co-localizes with theta in structures at or near the nuclear surface and in microtubules associated with the microtubule organizing center (MTOC). In summary, the present study demonstrates that seven PKC isoforms are endogenously expressed in B16F10 melanoma cells. These isoforms show various levels of induction by serum and specific patterns of association with various components of the detergent-resistant cell cytoskeleton.

Acetone↗
PubMed2000

Oscillatory curie temperature of two-dimensional ferromagnets.

The effective exchange interactions of magnetic overlayers Fe/Cu(001) and Co/Cu(001) covered by a Cu-cap layer of varying thickness were calculated in real space from first principles. The effective two-dimensional Heisenberg Hamiltonian was constructed and used to estimate magnon dispersion laws, spin-wave stiffness constants, and overlayer Curie temperatures within the mean-field and random-phase approximations. Overlayer Curie temperature oscillates as a function of the cap-layer thickness in a qualitative agreement with a recent experiment.

Journal Article↗
PubMed2000

Analysis of heavy metals in atmospheric particulate by ion chromatography.

Cu, Ni, Zn, Co, Fe+2, Mn, Cd, Fe+3 and Pb are easily separated and detected in isocratic mode by ion chromatography with post-column derivatization using a bifunctional ion-exchange column and an eluent formed by oxalic acid (28 mM) and sodium nitrate (250 mM). The separation is optimised by using a suggested sample solution containing a given concentration of chloride. Detection limits were 10-15 ppb for all the metals except for cadmium and lead, for which detection limits of 30 and 60 ppb were found, respectively. The method was tested on an atmospheric particulate certified sample. The measured values were in good agreement with certified values. Real samples of atmospheric particulate from industrial and urban sites were analysed and the results are discussed.

Air Pollutants↗
PubMed2000

Detection of spirochaetes of Borrelia burgdorferi complexe in the skin of cervids by PCR and culture.

To determine whether deer may play a role in the cycle of the Lyme disease spirochete Borrelia burgdorferi, we sought evidence for the presence of the pathogen in skin of deer and roe deer. Biopsies of 2 mm3 were taken at four different levels from nail to tarsus. A total of 50 animals (200 biopsies) were shot in the Lyme disease foci of Rambouillet during the hunting season 1995-1996 and 1996-1997, from the beginning of November to the end of February. Borrelia burgdorferi s.l. DNA was detected by PCR in 18 biopsies from 14 animals (28%). Borrelia burgdorferi s.str. was predominant (50%), followed by B. garinii (30%) and B. afzelii (10%). Multiple infections were detected in four animals: same species at different levels or two different species from the same biopsy or from different biopsies from the same foot. A total of 125 biopsies were cultivated on BSKH medium. Cultures at 160 days revealed immobile spiralled forms in 10 cultures. One, from a deer killed at the end of December, was confirmed by PCR as B. burgdorferi s.str. These results, frequency of detection of spirochetes by PCR in the skin, multiple infections and alive spirochetes in biopsies taken out side the season of activity of ticks strongly suggest an affinity of Lyme disease spirochetes for skin of cervids.

Animals↗
PubMed2000

Analysis of polycyclic aromatic hydrocarbons in the atmospheric particulate: focused microwaves for a faster extraction method.

In this paper, improvements obtained by using focused microwaves for extraction, in the analysis of polycyclic aromatic hydrocarbons (PAHs) adsorbed on particulate matter, are discussed. The method was tested on the following PAHs, which are considered to be among the most harmful with regard to carcinogenicity: benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenzo[a,h]anthracene. The extraction of PAHs and concentration of the sample can be performed in 3 h with a recovery of at least 70% and a maximum standard deviation of 4%. These steps are followed by clean-up on a SPE (solid-phase extraction) cartridge and analysis by GC-MS. Real samples collected in the urban area of Bari were analysed according to the proposed procedure.

Air Pollution↗
PubMed2000

Accuracy of EEG dipole source localisation in presence of brain lesions.

Inverse solution techniques based on electroencephalographic (EEG) measurements are a powerful mean of gaining knowledge about brain functioning, being used to estimate location, orientation and strength of neural electrical sources of brain activity. A model of the head, a model of the source and an electric-field computational method are necessary to describe the EEG problem mathematically. Volume conductor models commonly used to describe the EEG neglect the presence of brain lesions. We evaluated the need of considering brain lesions in head models for precise mapping of neural activity nearby the lesion, as it is requested for neurosurgical preoperative planning. A systematic evaluation of the effects of neglecting brain lesions in EEG dipole source localisation accuracy has been performed by computer simulations for different pathologic conditions, source types and source positions. Simulations of EEG measurements were carried out using a modified eccentric-spheres model of the head in which an eccentric bubble approximates effects of actual brain lesions. A three concentric spheres model has been used in the inverse dipole fitting procedure to quantify source localisation errors caused by ignoring the presence of lesions in the head model. 64 different situations have been analysed. Source reconstruction errors resulted negligible only for some relative positions of source, lesion and electrodes. The largest errors, up to 2.5 cm, have been found for a lesion placed between source and electrodes and for a source internal to the lesion (not circumscribed tumours). We conclude that source localisation process is largely affected by a nearby lesion and thus electrical mapping of brain activity must be performed embedding brain lesions in the head model.

Brain Diseases↗
PubMed2000

Necrotizing granulomata of the aortic valve in Wegener's disease.

Wegener's disease is an inflammatory disease of unknown etiology, characterized by a granulomatous-necrotizing general vasculitis. Cardiac involvement in the form of aortic pathology is not frequent. We report a case of Wegener's granulomatosis which required prosthetic aortic valve replacement for aortic valve insufficiency. Microscopic examination of the valve demonstrated histopathology typical of Wegener's disease.

Aortic Valve↗
PubMed2000

[Platysma myocutaneous flap in oral cavity reconstruction].

Repairing soft oral tissues which have been removed for oncological reasons is as dauting as it is important. Currently there are many, often sophisticated, methods available but any search for the best possible results must also cause the least patient trauma. The pedicled myocutaneous platysma flap is not new to oral cavity reconstruction although it is not very widespread. We have occasionally used this surgical anatomy, the cases are presented. This flap was performed in 10 cases and proved quite effective; there was no case of total failure as indicated by an orocutaneous fistula. Cutaneous necrosis, partial or total, was seen in 4 cases although it did healed by second intention. The other reconstructive methods are then discussed along with the indications and contraindications as well as some technical insight. One can conclude that the myocutaneous platysma flap is a relatively simple, highly versatile solution although reliability is not the best. The Authors conclude that it is advisable for the surgeon to include the myocutaneous platysma flap as part of his therapeutic arsenal.

Carcinoma, Squamous Cell↗
PubMed1999

Patent side branches do not affect coronary blood flow in internal thoracic artery-left anterior descending anastomosis: an experimental study.

BACKGROUND: It has been reported that large side branches of internal thoracic artery grafts may steal flow from the coronary circulation. Material an. METHODS: To assess the importance of the side branches, we measured the proximal and distal flow and pressures (mean subclavian artery pressure and mean arterial anastomotic pressure) at baseline and during infusion of adenosine (0.5 mg/kg/min) in 10 Landrace pigs in which an internal thoracic artery-left anterior descending anastomosis was constructed without interruption of the side branches. The difference between proximal and distal flow was considered to represent the blood flow of the internal thoracic artery side branches. Measurements were then repeated after surgical occlusion of all the side branches. RESULTS: At baseline, blood flow of the side branches represented 18% of the total flow in the proximal internal thoracic artery, and this percentage remained constant under the infusion of adenosine, which caused a 220% increase of the cardiac index and a 368% increase of the proximal flow. The infusion reduced the gradient along the left internal thoracic artery (mean subclavian artery pressure-mean arterial anastomotic pressure) from 15 to 10 mm Hg (P =.02) as the result of a lower mean subclavian artery pressure, although the mean arterial anastomotic pressure remained constant. Interruption of all the side branches resulted in a small and not significant increase in distal flow even after adenosine infusion. CONCLUSION: These observations suggest that blood flow in the side branches is minimal either at baseline and under combined systemic and coronary vasodilation. Clinically significant flow steal from the coronary circulation to the internal thoracic artery side branches seems then unlikely.

Anastomosis, Surgical↗
PubMed1999

Do internal mammary artery side-branches have the potential for haemodynamically significant flow steal?

OBJECTIVE: To evaluate the potential for flow steal of the internal mammary artery (IMA) side-branches at rest and in case of dilatation of their vascular bed (as probably occurs during physical exercise). METHODS: Transthoracic echo-Doppler evaluation of IMA flow was performed preoperatively in 40 patients undergoing myocardial revascularization. IMA flow was measured at rest and in condition of peripheral vasodilatation (obtained using forced ventilation for 2 min, dypiridamole 0.84 mg/kg endovenous (e.v.), xantinole nicotinate 500 mg e.v., nifedipine 20 mg sublingual (s.l.)). RESULTS: IMA mean peak systolic velocity increased 23% after forced ventilation (from 67 to 83 cm/s), 6% after dypiridamole (from 75 to 80 cm/s), 30% after xantinole infusion (from 62 to 81 cm/s) and 23% after nifedipine administration (from 60 to 74 cm/s). IMA flow increased 17.7% after forced ventilation (from 39.5 to 46.5 ml/min), 4.8% after dypiridamole (from 39.2 to 41.1 ml/min), 20.2% after xantinole infusion (from 41.4 to 49.8 ml/min) and 16.5% after nifedipine administration (from 41.6 to 48.5 ml/min). CONCLUSIONS: The limited functional flow reserve of the in situ IMA, even after pure muscular vasodilatation, seems to minimize the possibility of significant flow steal from patent IMA graft collaterals.

Aged↗
PubMed1999

Perioperative management of a patient with Werlhof disease undergoing myocardial revascularization.

We herein report the case of a patient with idiopathic thrombocytopenic purpura (Werlhof disease) and coronary artery disease undergoing myocardial revascularization. The use of monomeric immunoglobulins, corticosteroids, platelets transfusion, use of a cell saver, normothermic cardiopulmonary bypass, aprotinine and homologous blood transfusion were combined in order to minimize the risk of bleeding complications in the postoperative period.

Aged↗
PubMed1999

Internal mammary artery grafts and competitive flow. Controversies persist.

We report one case in which chronic native competitive flow from an almost normal target coronary artery did not influence IMA graft patency. This patient underwent control postoperative angiography 11 months after surgery and the mammary artery-left anterior descending graft was found to be normofunctioning despite the fact that the coronary artery showed no residual stenosis.

Coronary Angiography↗