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P Rubini

Publications and source records attributed to P Rubini.

At least 19 recordsLinked to original sources
PubMed2005

A multi-approach study of the interaction of the Cu(II) and Ni(II) ions with alanylglycylhistamine, a mimicking pseudopeptide of the serum albumine N-terminal residue.

The protonation equilibria of alanylglycylhistamine (Ala-Gly-Ha) and the complexation of this ligand with Cu(II) and Ni(II) have been studied by pH-potentiometry, 1H and 14N NMR spectroscopy, electrospray ionization mass spectrometry (ESI-MS), circular dichroism (CD), UV-Vis spectrophotometry and electron paramagnetic resonance (EPR). From pH approximately 2-12, the following complexes: MLH, MLH(-1), MLH(-2) and MLH(-3) are successively formed in aqueous solutions, the ligand under its neutral form being noted L. At physiological pH, the MLH(-2) complex is predominant. The coordination in this complex is assumed by one amino, two deprotonated peptide and one imidazole nitrogen atoms. The ESI-MS study confirmed the formation of the MLH(-1), MLH(-2) and MLH(-3) complexes. The structure of MLH(-2) was determined by single crystal X-ray analysis. CD and UV-Vis techniques allowed us to propose that the imidazole-N3 nitrogen acts as the anchor group for the coordination to the metal(II) ions rather than the amino group. At high pH values, the further deprotonation of the N-H imidazole group, leading to the formation of MLH(-3), occurs, as revealed by 1H NMR spectroscopy.

Circular Dichroism↗
PubMed2004

Somatic and axonal effects of ATP via P2X2 but not P2X7 receptors in rat thoracolumbar sympathetic neurones.

Excitatory ATP responses in rat cultured thoracolumbar sympathetic neurones are mediated by somatic P2X(2) receptors. The present study investigated a possible role of axonal P2X(2) as well as P2X(7) receptors on the same preparation. Confocal laser scanning microscopy demonstrated P2X(2) and P2X(7) immunoreactivity along the axons as well as P2X(7) immunoreactivity surrounding the cell nuclei. P2X(7) mRNA expression was detected in individual neurones using a single-cell RT-PCR approach. Adenosine triphosphate (ATP) caused a significant increase in axonal Ca(2+) concentration which was dependent on external Ca(2+) but insensitive to depletion of the cellular Ca(2+) pools by cyclopiazonic acid. Pyridoxal-phosphate-6-azophenyl-2',4'-disulfonate (PPADS; 30 micro m) virtually abolished the ATP response, whereas brilliant blue G (0.1 micro m), a selective P2X(7) receptor antagonist, had no effect. Dibenzoyl-ATP (BzATP; 100 micro m) induced a much smaller increase in axonal [Ca(2+)] concentration than ATP at equimolar concentrations. The response to BzATP was distinctly reduced by PPADS but not by brilliant blue G. The overall pharmacological profile of the axonal P2X receptors resembled closely that of the somatic P2X(2) receptors. In conclusion, the present data suggest the occurrence of axonal excitatory P2X(2) receptors in thoracolumbar sympathetic neurones. However, the functional significance of axonal and (peri)-nuclear P2X(7) receptors has still to be proven.

Adenosine Triphosphate↗
PubMed2003

Interactions of aluminium(III) with glycerolphosphates and glycerophosphorylcholine.

The complexation of aluminium(III) with glycerol-1-phosphate (G1P) and glycerol-2-phosphate (G2P) in aqueous solutions has been studied as a function of pH, by pH-potentiometry, 31P NMR spectroscopy and ESI mass spectrometry. Various mononuclear complexes (MLH(2)(3+), MLH(2+), ML(+), ML(2)H, ML(2)(-)) and polynuclear species (M(3)L(3)H(-1)(2+), M(3)L(2)H(-n)((n-5)-) with n=5, 6, 7, M(2)L(2)H(-1)(+) ) are formed in the system where the full protonated ligands are noted LH(2). NMR experiments clearly show that G1P and G2P already interact with Al(III) at pH 1. The potentiometric results are confirmed by ESI measurements and 31P NMR studies. No metal ion-induced deprotonation and coordination of the alcoholic-OH functions seem to occur during the complexation. The situation is very different for the glycerophosphorylcholine ligand (GPC identical with LH). Only the complex ML(3+) is formed in aqueous solution with a relatively low formation constant (K=5 at 37 degrees C). This species is clearly identified in 31P and 27Al NMR spectra. The complexation study as a function of the temperature allowed us to determine the thermodynamic parameters of the complex formation. The complexation is not governed by the reaction enthalpy that is found to be positive but by the entropy that is largely positive.

Aluminum↗
PubMed2001

Gallbladder injury in blunt abdominal trauma.

A 36-year-old woman was admitted to the hospital for an abdominal blunt trauma. At ultrasound (US) and computed tomography (CT), a gallbladder lesion was suspected, along with a tear of the liver. The patient was submitted to a diagnostic laparoscopy. The gallbladder was partially avulsed and bile was infiltrated in the hepatoduodenal ligament. Intraoperative cholangiography and Kocher's maneuver excluded other lesions. Laparoscopic cholecystectomy was performed, but due to severe hemorrhage from the liver tear, the operation was converted to an open procedure. Gallbladder lesions in blunt trauma are rare occurrences, but they are often associated with other organ injuries. US and CT scan are valuable for their diagnosis, but if a lesion is suspected, diagnostic laparoscopy is advisable in stable patients. It should be accompanied by a cystic duct cholangiography and a Kocher's maneuver to evaluate the integrity of the biliary tree. Laparoscopic cholecystectomy is generally feasible. Associated lesions require laparotomy when they are not amenable to laparoscopic treatment.

Abdominal Injuries↗
PubMed2001

Potentiometric and spectroscopic studies on the dimethyltin(IV) complexes of 2-hydroxyhippuric acid.

Equilibrium and spectroscopic (1H, 13C NMR and 119Sn Mössbauer) studies in aqueous solution are reported for dimethyltin(IV) complexes of 2-hydroxyhippuric acid (Sal-Gly). Below pH 4, oxygen-coordinated complexes MLH and ML are formed. In the pH range 5-8.5, the species MLH(-1), predominates at any metal-to-ligand ratio. The ligand exchange of this species is slow on the NMR time scale, which allows its structural characterization by NMR spectroscopy: the coordination polyhedron around the tin atom is distorted trigonal bipyramidal, with tridentate [O-,N-,COO-] coordination of Sal-Gly, involving two equatorial methyl groups. The NMR results reveal that the main cause of the distortion of the polyhedron is the large CH3-Sn-CH3 angle of 136+/-4 degrees. The presented results supplement the data available on the dimethyltin(IV)-promoted amide deprotonation of peptides, and provide further arguments for the fundamental role of the carboxylate as an anchoring group in this process.

Electrochemistry↗
PubMed2001

Complexes of aluminium(III) with glucose-6-phosphate in aqueous solutions.

The interaction of aluminium(III) with glucose-6-phosphate (GP: LH2) in aqueous solutions has been studied from pH 1 to pH 8, by pH-potentiometry and multinuclear (31P, 27Al, 13C) NMR spectroscopy. Various mononuclear species (MLH2, MLH, ML, ML2H, ML2 and MLH(-3)) and dinuclear complexes M2L2H-n (n=1-4) are formed in the system. NMR clearly indicates that GP is already bound to Al(III) at pH 1. The potentiometric speciation results are confirmed and completed by spectroscopic experiments. Many peaks are observed in the 31P NMR spectra suggesting the formation of isomeric species. An attempt to assign the signals to the corresponding complexes is made, allowing a discussion about their structure. Interestingly enough no metal ion-induced deprotonation and coordination of the alcoholic-OH functions have been observed.

Aluminum↗
PubMed2001

[Inflammatory abdominal aortic aneurysms].

The authors present a review of the literature on inflammatory abdominal aortic aneurysms. These aneurysms represent from 3 to 10% of all abdominal aortic aneurysms. Progress has occurred in the technical approach to these aneurysms, and operative morbidity and mortality have been remarkably reduced. However, the pathogenesis remains poorly understood. Early reports have considered the inflammatory aneurysm as a distinct clinical and pathological entity, whereas recent evidences suggest a common etiopathogenetic mechanism for both atherosclerotic and inflammatory aneurysms. Finally, genetic and environmental factors, such as tobacco use, may predispose certain persons to the development of non-inflammatory aneurysms and others to a wide spectrum of inflammatory reactions until inflammatory aneurysms development. The most common clinical features of these aneurysms are represented by symptoms, such as abdominal or back pain, obstructive uropathy and by an elevated erythrocyte sedimentation rate. Computed tomography (CT) allows a specific diagnosis by the typical image of soft tissue surrounding the aortic wall enhancing with contrast administration. Ultrasonography is less sensitive whereas nuclear magnetic resonance (RNM) is a promising technique. Excretory urography may suggest the diagnosis by demonstration of ureter entrapment. Surgical therapy, by a technique of limited dissection represents the definitive treatment. Evolution of fibrosis after surgery is still debated because some studies have reported complete regression of inflammation and other partial regression or persistence of fibrotic process. At present, endovascular treatment of these aneurysms is occasionally reported, although preliminary results appear satisfactory.

Aortic Aneurysm, Abdominal↗
PubMed2001

[Prevalence of atherosclerosis in renal transplant recipients].

BACKGROUND: Cardiovascular diseases are a major cause of morbidity and mortality after kidney transplantation. Renal transplant recipients have in fact accelerated atherosclerosis because of prolonged hemodialysis, arterial hypertension, dyslipidemia and other vascular risk factors. Studies concerning carotid and lower limb atherosclerotic changes in renal transplanted patients are at present scant. METHODS: In the present study the prevalence of carotid and iliac-femoro-popliteal atherosclerosis was evaluated by color flow Doppler in 99 patients 64 +/- 41 DS months after renal transplantation. Statistical analysis was used to correlate the presence and grade of atherosclerotic lesions with vascular risk factors and other clinical-laboratoristic parameters of the patients. RESULTS: The overall incidence of atherosclerotic lesions in the population studied was 54.5%; 46.5% of patients presented atherosclerotic plaques at carotid district, 43.4% at lower limb arteries and 35.4% at both districts. Two of these patients were symptomatic; one patient affected by claudicatio intermittens was submitted to conservative therapy, whereas another patient with abdominal aortic aneurysm underwent to surgical treatment. Univariate analysis showed a significant difference between males and females for lower limb atherosclerotic lesions (p=0.0013), whereas no correlation was found between carotid lesions and sex, or between smoke and atherosclerosis. Significant correlations were found by multiple correlations analisys between: the grade of atherosclerotic lesions in both districts and the patient age (p<0.0001); the grade of carotid atherosclerotic plaques and duration of pretransplantation dialysis (p<0.01); the grade of lower limb atherosclerosis and respectively glicemic (p<0.01), hematocrit (p<0.01), potassium (p<0.002) values, systolic blood pressure (p<0.02). CONCLUSIONS: Relevant rates of renal transplant recipients have carotid and peripheral atherosclerotic lesions. The study of aorto-iliac and lower extremity vascular atherosclerosis have important implications for the transplanted kidney functionality. Color flow Doppler represents a sensitive method for the follow-up examination of these patients.

Adult↗
PubMed2000

The radial artery: which place in coronary operation?

Previous long-term studies have shown unsatisfactory patency of saphenous vein grafts, compared with internal mammary artery grafts. Recently, the use of the radial artery as a coronary artery bypass graft has enjoyed a revival, on the basis of the belief that it will help improving long-term results of coronary operations. The recent report of encouraging 5-year patency rates, supports its continued use as a bypass graft. In this paper, we review the current knowledge about the radial artery as a bypass graft, with special emphasis on the clinical results.

Coronary Artery Bypass↗
PubMed2000

Coronary and major vascular disease: aggressive screening and priority-based therapy.

It is well know that atherosclerosis can simultaneously affect different vascular subsystems, and patients with diffuse atherosclerosis can be a major management problem both for preoperative evaluation and for intraoperative management. The authors have conducted a prospective study to evaluate the prevalence of coronary artery disease in arteriopathic patients, and vice versa, to assess the effectiveness of aggressive screening together with a priority-based approach. Study 1 consisted of 1,000 consecutive non-emergent patients who were affected by abdominal aortic or carotid disease and were screened for the presence of coronary artery disease before surgery with a newly developed clinical risk assessment. They were stratified into three risk categories with different preoperative evaluation strategies. When coronary artery disease was concomitantly demonstrated in these patients, the choice of surgical method was based on priorities, and the use of combined surgical procedures as required. In study 2, 1,000 consecutive patients that required coronary angiography for suspected coronary artery disease were screened for the presence of carotid or abdominal aortic pathology, directly in the cardiac catheter laboratory during coronary angiography, by obtaining views of the aortic arch and abdominal aorta. Surgical approaches paralleled those of study 1. The results for study 1 showed that 720 patients (72%) were affected by abdominal aortic disease, 238 (24%) by carotid disease and 42 (4%) by both pathologies. Significant coronary artery disease was found in 152 patients (15%), of these 123 (81.5%) were affected by abdominal aortic disease and 29 (18.5%) by carotid artery disease. Abdominal aortic surgery was performed directly or after myocardial revascularization, with an overall mortality rate of 4/718 (0.6%), and a perioperative myocardial infarction rate of 10/718 (1.4%). For patients with carotid artery disease, the completed screening and possible therapy for coronary artery disease resulted in an in-hospital mortality rate of 2/238 (0.8%), and a perioperative myocardial infarction rate of 2/238 (0.8%). There were no significant differences in these rates between patients with or without coronary artery disease. Results for study 2 showed that of the 1000 consecutive patients enrolled for suspicion of coronary artery disease, 767 (77%) were affected by significant coronary artery disease. Among these, 38 (4.9%) had a surgically correctable aortic disease and 31 (4%) a surgically correctable carotid disease, which was monolateral and bilateral in 22 (74%) and nine (26%) patients, respectively, and four (0.5%) were diagnosed with both pathologies. These arteriopathic patients were treated for their coronary and vascular disease with no in-hospital mortality nor perioperative myocardial infarction. In patients with multiple vascular involvement, both coronary and vascular surgery can be performed with low risk when aggressive screening and priority-based therapy are adopted.

Angioplasty, Balloon, Coronary↗
PubMed2000

[Diagnosis and treatment of pheochromocytoma].

Early detection of a pheochromocytoma is necessary to avoid the cardiovascular complications of hypertension and to recognize the 10% of malignant neoplasms. Hypertensive changes, particularly hypertensive spikes and stable hypertension are the most common clinical features. A pheochromocytoma must be suspected in presence of various symptoms of which cephalea, tachycardia, diaphoresis are the most frequently encountered. Plasma catecholamines and 24-hours urine metabolites measurements have 60-100% and 72-99% sensitivity respectively. Radiologic procedures commonly used to locate a pheochromocytoma include CT and RM: they achieve 100% sensitivity for unilateral adrenal lesions and respectively 64% and 88% sensitivity for extra-adrenal lesions. Scintigraphic localization with MIBG provides functional informations and is recommended for follow-up of the recurrent or metastatic pheochromocytoma. Preoperative medical treatment using alpha and beta blocking agents or calcium channel blockers has contributed to reduce perioperative morbidity and mortality. Anterior transabdominal approach is advocated as the standard operative procedure; this approach allows ready access to any site where tumors are obviously present and permits thorough exploration of the abdominal cavity for additional contralateral adrenal or extra-adrenal lesions. An accurate preoperative localization of a sporadic, unilateral, of less than 7-10 cm, benign neoplasm constitutes the indication for the laparoscopic adrenalectomy. Pheochromocytoma-free survival were 92% and 80% at 5 and 10 years respectively; in living patients without recurrence, hypertension-free survival was 74% and 45% at 5 and 10 years respectively. Extra-adrenal pheochromocytomas are frequently malignant (36%) and are associated with a high incidence of persistent or recurrent disease (32%).

Adrenal Gland Neoplasms↗
PubMed1999

[Assessment and treatment of incidentally discovered adrenal tumors].

An incidentally discovered adrenal mass involves two main questions: the first is the evaluation of the hormonal activity of incidentalomas, that by definition are considered clinically silent. The second problem is to establish preoperatively the biologic behaviour of the masses, whether they are benign or malignant. An essential endocrinological screening of these masses includes the 24 hour urine VMA determination, serum potassium level, and a 1 mg overnight dexamethasone suppression test. Furthermore, the recent observation of a possible partial deficit of 21-hydroxylase suggests the advantage of 17-hydroxyprogesterone dosage after ACTH stimulation. At present no biochemical or radiologic markers can reliably distinguish benign from malignant masses. For this reason the association of imaging study with scintigraphy seems to be helpful, providing "concordant" or "discordant" patterns with CT images. As regard to therapeutic indications, the resection of all hypersecretive masses, proved malignant or increased in diameter tumors is suggested. As regards to biochemically silent lesions, the tumor size has been deemed to be the most helpful determinant of the nature although controversy remains over the size cutoff below which the masses can safely be presumed to be benign and therefore observed. The threshold to proceed surgically has been based on the perceived risk of cancer balanced against the operative risk. However it seems reasonable to recommend excision or surgical exploration for hormonally silent tumors greater than 3 cm, particularly in younger patients. According to personal opinion the laparoscopic approach might represent the gold standard in the treatment of incidentally discovered adrenal masses.

Adrenal Gland Neoplasms↗
PubMed1998

[Uninodular bronchioalveolar carcinoma. Apropos of 10 operated cases].

BACKGROUND: This study reports 10 cases of uninodular bronchiolo-alveolar carcinoma (BAC) operated on in the General Surgery and Organ Transplantation Institute of the University of Parma between January 1st 1981 and December 31st 1995. METHODS: Seven patients were males and three females, mean age was 65 (DS 11, range 37-75) and globally accounted for 6.4% of all surgically treated lung malignant tumors. RESULTS: Hospital mortality was null; one patient was treated with assisted ventilation four days after surgery for respiratory insufficiency. Actuarial survival at 36 and 60 months was 48% and 36% respectively; survival rates were not significantly different at log-rank test from squamous carcinoma (46.2% at 36 months, 35% at 60 months) and adenocarcinoma (50.5% at 36 months, 34.3% at 60 months). The analysis of other series of literature shows significantly higher survival rates at 5 years for BAC than for adenocarcinoma (55.6% vs 40%). CONCLUSIONS: Broader series are needed for statistical confrontation with other histological types by stage and grade. There is no evidence of peculiar prognostic or clinical features in this histological type of pulmonary malignancy, prognosis so far is in fact conditioned by the same factors of other non small cell lung carcinomas.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1998

[Carcinoid of the appendix. Observations on 4 cases].

Four cases of carcinoid tumors of the vermiform appendix are reported. Clinical presentation in 3 cases was suggestive of acute appendicitis and they were submitted to appendicectomy. The carcinoid tumor was discovered by the pathologist on specimen of appendix. The tumors's size, less than 2 cm, the absence of serosal involvement and lymphatics invasion suggested that simple appendicectomy was a satisfactory treatment for such patients. Occasionally clinical presentation of appendiceal carcinoid is characterized by symptoms of intestinal obstruction or intussusception, palpable mass, bleeding. In the fourth patient, that had symptoms consistent with ileal occlusion, we found at laparotomy a bulky tumor of the base of appendix infiltrating and obstructing the cecum and right colon, without liver metastases. A right hemicolectomy with end-to-end anastomosis was performed. Aggressive behaviour of this tumor was also revealed by the single pulmonary metastasis, finding very uncommon in carcinoid of appendix. This patient died postoperatively, at 25th day, of septic abdominal complications, secondary to anastomotic leak. The former patients at clinical and radiological (CT scan) follow-up performed at 3, 12, 36 months respectively, are still alive and disease free.

Adolescent↗
PubMed1997

[Hemorrhagic pseudocyst of the adrenal gland: a case report].

A case of haemorrhagic cyst of the adrenal gland (pseudocyst) is reported. The interest is related to the histologic and pathogenetic aspects which are still controversial. In this case the cyst may be explained as a consequence of an hamartomatous vascular anomaly or as a traumatic consequence: the histopathological finding characterized by the presence of irregular vascular channels in the outer fibrous wall of the cyst may suggest that haemorrhage occurred in a preexisting blood vascular anomaly, whereas the anamnestic information of a trauma in the past suggests a traumatic origin of the mass. Clinical findings were characterized by lumbar tension and pain without palpable mass; the specific diagnosis was made preoperatively by ultrasonography and CT scan of the abdomen. Left adrenalectomy was performed through an anterior extraperitoneal approach following a supraumbilical incision.

Adrenal Gland Diseases↗
PubMed1996

[Clinical suspicion and instrumental diagnosis of ruptured aneurysm of the abdominal aorta. Analysis of our experience].

The authors report their experience in the management of 54 patients who underwent emergency surgery for rupture of an abdominal aortic aneurysm, correlating results to time of diagnosis. The overall mortality rate was 55.5%. The extent and the site of bleeding, free blood in peritoneal cavity or retroperitoneal hematoma alone, were critical factors influencing survival and were correlated to early of diagnosis. Patients with small hematomas had no mortality; cases with more extensive hematomas had a mortality rate of 53%; in case of intraperitoneal bleeding the mortality rose to 73% (p = 0.001). The median times between symptoms' onset and surgical intervention was correlated with a significant value to extent of retroperitoneal hematoma (p = 0.003). This time is also significantly different in dead patients compared to survivors (p < 0.001). In patients with incorrect admitting diagnosis the mean times between onset of symptoms and surgical treatment was significantly different from time of correctly diagnosed patients (p < 0.001). Our findings emphasize the need for rapid recognition of prodromal symptoms of rupture and the earlier referral of patients with known abdominal aneurysm; we suggest that in an unstable patient with a suspected ruptured aneurysm immediate surgery should be performed without delay for confirmatory tests or full resuscitation.

Aged↗