PubMed Health⌕ Search

Biomedical subjects

R Vinci

Publications and source records attributed to R Vinci.

At least 19 recordsLinked to original sources
PubMed2006

Double-contrast MRI (DC-MRI) in the study of the cirrhotic liver: utility of administering Gd-DTPA as a complement to examinations in which SPIO liver uptake and distribution alterations (SPIO-LUDA) are present and in the identification and characterisation of focal lesions.

PURPOSE: The aim of this study was to compare the performance of double-contrast magnetic resonance imaging (DC-MRI) with the sequential use of superparamagnetic iron oxide (SPIO) and gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) contrast agents compared with unenhanced MRI and SPIO-enhanced MRI (SPIO-MRI) in the study of the cirrhotic liver. Special attention was paid to cases in which alterations of liver uptake and distribution of the SPIO contrast medium [SPIO-liver uptake and distribution alterations (SPIO-LUDA)] could lead to diagnostic errors at SPIO-MRI. MATERIALS AND METHODS: We used DC-MRI to study 67 patients suffering from hepatic cirrhosis and on a waiting list for liver transplant. The study was performed with a 1.5-Tesla device and characterised by three phases: the first phase without contrast material (unenhanced MRI), the second after the administration of ferumoxides (SPIO-MRI), and the third, a double-contrast study following the injection of a bolus of paramagnetic contrast material (DC-MRI). The sensitivity of unenhanced MRI, SPIO-MRI and DC-MRI in identifying and characterising hepatic focal lesions was assessed, together with the diagnostic increment of one technique with respect to the others. The gold standard was histological confirmation in 38 cases and clinical-radiological follow-up in all cases. Liver function, kidney function, blood tests and urinalysis were performed in all patients 24-48 h before and after the MRI examination. RESULTS: In 14/67 cases (20.8%), SPIO-LUDA were present, which posed a limitation to the SPIO-MRI examination. Focal lesions were absent in 44 patients, and the action of the ferumoxides was reduced by the presence of SPIO-LUDA in nine cases. There were five cases of confluent fibrosis, two of decompensated cirrhosis, one of vascular thrombosis, and one of scarring in a patient who had undergone hepatic resection for hepatocellular carcinoma (HCC). In all these cases, completion of the MR examination with the DC technique clarified the MR picture, confirming the absence of focal lesions. Twenty-three patients had a total of 68 lesions, which consisted of 37 dysplastic nodules (DN), 19 HCC nodules, two relapses of HCC following chemoembolisation, two HCC associated with portal thrombosis, one cancer-cirrhosis, two angiomas and five small cysts. SPIO-LUDA were present in five patients, thus limiting the identification, characterisation or assessment of the real size of the lesions. SPIO-LUDA were the result of vascular thrombosis in one case and fibrosis in four cases. In all of these cases, DC-MRI proved useful for diagnosis. The sensitivity of unenhanced MRI, SPIO-MRI and DC-MRI for lesion detection was 57.3%, 67.6% and 75%, respectively. The results obtained in the characterisation of the lesions were 20.5%, 63.2% and 73.5% for unenhanced MRI, SPIO-MRI and DC-MRI, respectively. The diagnostic increment of SPIO-MRI over unenhanced MRI for lesion identification and characterisation was 9% and 42.7%, respectively, whereas the diagnostic increment of DC-MRI over SPIO-MRI was 7.4% and 10.3%, respectively. CONCLUSIONS: In our study, the combined use of two contrast agents, negative and positive, provided greater diagnostic confidence and caused no side effects in the patients.

Contrast Media↗
PubMed2001

Improved high-performance liquid chromatographic method to estimate aminosugars and its application to glycosaminoglycan determination in plasma and serum.

An improved isocratic high-performance liquid chromatography (HPLC) method for the analysis of L-(-)-fucose. D-(+)-galactosamine, D-(+)-glucosamine, D-(+)-galactose, obtained by hydrolysis of glycosaminoglycans (GAGs) and D-(+)-glucose and D-(+)-mannose is described. The presence in circulation of GAGs, acid polysaccharide sequences of alternate monosaccharide units, aminosugar and uronic acid (galactose in keratan sulfate), has been measured in terms of their sugar components. To evaluate concentration of these circulating sugars we considered blood samples obtained from healthy humans. Plasma or serum was filtered through weak anion-exchange Ecteola-cellulose either untreated or after mild alkaline treatment. GAGs adhering to resin were recovered by salt elution, and desalted on Bio-Gel P-2 resin. GAG fractionation by charge was carried out on a strong anion exchanger. GAG composition was evaluated in terms of galactose and aminosugars, measured in HPLC by the proposed procedure using anion-exchange resin and pulsed amperometric detection. The mobile phase consisted of 0.02 M NaOH and elution was carried out at flow-rate of 1.0 ml/min. The amperometric detector was set as follows: t1 (0.5 s), E1 (+0.1 V); t2 (0.09 s), E2 (+0.6 V); t3 (0.05 s), E3 (-0.6 V). The analysis required 14 min. Calibration standard curves for the six analytes were linear from 0.25 to 40 microM. RSD values for intra- and inter-day variabilities were < or = 5.3% at concentrations between 0.25 and 40 microM. Accuracy, expressed as percentage error, ranged from - 16 to 14%. The method was specific and sensitive with quantitation limits of 1 pmol for L-(-)-fucose, D-galactosamine and D-glucosamine, 3 pmol for D-(+)-galactose and D-(+)-glucose and 5 pmol for D-(+)-mannose. The results of the assay showed higher GAG concentrations in serum than in plasma.

Amino Sugars↗
PubMed2000

Abdominal wall hernias: imaging with spiral CT.

Computed tomography is an accurate method of identifying the various types of abdominal wall hernias, especially if they are clinically occult, and of distinguishing them from other diseases such as hematomas, abscesses and neoplasia. In this study we examined the CT images of 94 patients affected by abdominal wall hernias observed over a period of 6 years. Computed tomography clearly demonstrates the anatomical site of the hernial sac, the content and any occlusive bowel complications due to incarceration or strangulation. Clinical diagnosis of external hernias is particularly difficult in obese patients or in those with laparotic scars. In these cases abdominal imaging is essential for a correct preoperative diagnosis and to determine the most effective treatment.

Aged↗
PubMed2000

Dismantling and reassembling of the facial skeleton in tumor surgery of the craniomaxillofacial area. History, surgical anatomy, and notes of surgical technique: Part 1.

In recent years, access osteotomies have been suggested to reach areas of the craniofacial skeleton that hitherto would not have been easily resectable. Some techniques of disassembling of the facial skeleton have been described in the past. In some cases, however, when the bony fragments were not pedicled to the soft tissue, reabsorption was noted. For this reason, new dismantling techniques with adequate blood supply to the bony fragments have been developed. Apart from the maxillo cheek flap, other composite flaps have been described. These flaps may be combined if necessary in selected cases. An overview of the surgical anatomy and surgical strategies will be presented. These reported techniques may be considered a major step forward in the treatment of deeply localized tumors in the craniomaxillofacial area.

Cheek↗
PubMed2000

[Renal arteriovenous fistulas after renal biopsy. Percutaneous embolization].

PURPOSE: We report our experience relative to transcatheter percutaneous embolization of post-biopsy renal intraparenchymal arteriovenous fistulas in patients with chronic renal insufficiency. MATERIAL AND METHODS: We observed 5 patients affected with post-bioptic fistulas for possible embolization. In three cases the symptoms were represented by intermittent macro-microhematuria; one patient had hypertension of nephrovascular origin and one patient was asymptomatic. In all cases we performed angiography and it was possible to catheterize the peripheral afferent branch of the fistula with a superselective technique using a hydrophilic guide of 0.035 F and a hydrophilic Cobra catheter of 4-5 F. The occlusion was obtained by the positioning of Granturco metal coils: in 1 case we adapted a coil of 3 mm diameter and 1 cm length; in 3 cases 2 coils of 3 mm and in 1 case 2 coils of 3 mm and 1 coil of 5 mm diameter and 1 cm length were necessary. The success of the procedure was always checked with an immediate angiogram and color Doppler US after 48 hrs. RESULTS: The diagnosis of arteriovenous fistulas was always confirmed by a preliminary angiography that demonstrated the normal anatomic disposition of the renal arteries except in one case in which the fistula was fed by a peripheral branch originating from an inferior polar artery. All the lesions were localized in the inferior pole, the site of biopsy, and ranged from 3 mm to 2.5 cm in diameter. We never had any difficulties in the positioning and placement of the coils. The arterial occlusion and exclusion of the fistula was accomplished in all cases. The induced parenchymal loss ranged from 10 to 30% of the renal volume. There was a complete disappearance of symptoms in 3 of the patients, with hematuria without any modification of the blood pressure values in the patient with hypertension. Considering the patient status renal function did not worsen after the embolization. Each patient was followed-up with color Doppler US every two months. CONCLUSIONS: The intrarenal arteriovenous fistula represents a relative frequent complication of renal needle biopsy in patients with arterial hypertension and nephroangiosclerosis as risk factors. Embolization is a valid alternative therapeutic option to surgical treatments. The use of small size catheters permits the successful embolization also of peripheral lesions, reducing the induced parenchymal ischemia. We believe that among the embolization material available metal coils represent a valid solution as they are easily positioned and permit definitive occlusion without any risks of systemic venous microembolization.

Adult↗
PubMed1999

[Vascular complications in intestinal obstructions. The role of computed tomography].

INTRODUCTION: We investigated CT capabilities in showing vascular complications (ischemia, infarction) secondary to intestinal obstruction. SUBJECTS AND METHODS: 32 patients with small bowel obstruction, subdivided in two groups, were examined with CT. The first group consisted of 12 patients with small bowel obstruction complicated by ischemic injury. It was due to loop strangulation in 10 cases and loop distension secondary to colon carcinoma in 2 cases. At surgery the loop strangulation was caused by adhesions in 9 cases and by jejunal hernia in 1 case. Vascular complications were segmentary small bowel infarction in 7 cases, colonic infarction in 2 cases and ischemia, which was resolved after loop debridement, in 3 cases. The second group consisted of 20 patients with intestinal occlusion due to adhesions complicated by a closed loop in 4 cases. All patients were examined with(out) i.v. contrast agent administration. Filling of the intestinal loops by oral contrast agent was never performed. RESULTS: CT identified the vascular injury secondary to intestinal obstruction in 11/12 patients (91%). In one case it was not possible to diagnose mild ischemia, which was found of surgery. CT findings were: loops distention in all the cases; wall thickening in 11 cases with intramural gas in 8 cases and slight contrast enhancement in 1 case; ascites in 2 cases; mesenteric edema in 9 cases; gas at the mesenteric root in 1 case. In the control group, small bowel obstruction was diagnosed with CT in all cases based on the presence of distended loops up to the occlusion site. Parietal alterations above the lesion were never found. CONCLUSION: CT is a sensitive tool for diagnosing small bowel obstruction and for assessing the site and cause of obstruction. CT plays a pivotal diagnostic role in vascular complications, giving very important indications for a correct treatment.

Humans↗
PubMed1998

Increased concentration of circulating acid glycosaminoglycans in chronic lymphocytic leukaemia and essential thrombocythaemia.

To verify whether the increase in the number of circulating blood cells that synthesize glycosaminoglycans, B-lymphocytes or platelets, in proliferative disorders, may be associated with changes in the circulation of acid glycosaminoglycans, the serum and plasma concentrations of these polysaccharides have been measured in terms of their sugar components, following isolation and purification by chromatographic methods, in patients with chronic lymphocytic leukaemia or with essential thrombocythaemia and in healthy controls. In the patients, the concentrations of total circulating glycosaminoglycans and of both glucosamine-containing and galactosamine-containing serum glycosaminoglycans were significantly higher than in controls. These concentrations did not significantly correlate with the number of lymphocytes in patients with chronic lymphocytic leukaemia and of platelets in patients with essential thrombocythaemia. Analytical data suggest that excess glycosaminoglycans are mainly composed of chondroitin sulphate molecules and contain heparan sulphate structures.

Adult↗
PubMed1998

[Computerized tomography findings in intestinal carcinoid].

INTRODUCTION: We studied the CT patterns of abdominal carcinoid tumors. MATERIAL AND METHODS: Eight patients with carcinoid tumors were examined with CT. The tumors were in the ileum (2 patients), duodenum (1), colon (1), and mesentery (4). Pathologic confirmation was obtained at surgery in all patients. The symptoms were the carcinoid syndrome in 2 patients, abdominal pain in 4, jaundice in 1 patient and a right lower quadrant mass in 1. All patients were examined with(out) i.v. contrast agent administration; 6 patients received oral contrast material and 2 were submitted to water enema, to enhance visualization of the distal ileum and colon. RESULTS: CT identified the tumor in all patients but correctly defined its site in 7 cases only. CT showed a small mass in the distal common bile duct in 1 case, which postoperative histology diagnosed as a malignant carcinoid tumor of the duodenum. The CT findings of carcinoid tumors were a rounded mesenteric mass displacing bowel loops in 4 cases, an infiltrating colonic tumor in 1 case, an apparently intracholedochal mass in 1, a large necrotic mesenteric mass in 1 case. CT showed lymph node involvement in 2 cases, but no liver metastases were found. A carcinoid tumor was diagnosed in 4 patients based on the typical CT finding of a mesenteric mass with radiating soft-tissue density bands resulting in a stellate pattern. No preoperative diagnosis was possible in some other cases because the CT patterns were aspecific and mimicked those of other lesions, namely of tumor of the distal common bile duct, adenocarcinoma of the right colon, submucosal tumor of the distal ileum, large necrotic mesenteric mass. CONCLUSIONS: CT is a useful tool in the detection of carcinoid tumors. The correct diagnosis can be made based on the characteristic CT finding of a rounded mesenteric mass. In our experience, however, carcinoid tumors may present with other CT patterns mimicking those of other tumors.

Aged↗
PubMed1997

[Blood flow assessment with Doppler color ultrasonography in primary and secondary tumors of the liver].

Our study was aimed at measuring hemodynamic changes in liver perfusion in patients with HCC and hepatic metastases using color Doppler US, a noninvasive investigation technique. Eighty-seven patients were examined: 14 of them had HCC and 34 had metastases; the control group consisted of 39 people. Blood flow was measured in the common hepatic artery and portal vein and the ratio of hepatic arterial to total liver blood flow (HPI = hepatic perfusion index) and the ratio of hepatic arterial to portal venous blood flow (A/V ratio) were calculated. HPI and A/V values were changed in HCC patients (HPI = 0.23, range: 0.16-0.35; A/V = 0.32, range: 0.19-0.55) as a consequence of reduced portal venous blood flow (9.76 +/- 2.51 cm3/s) and of increased hepatic arterial flow (2.78 +/- 0.46 cm3/s). HPI and A/V values were significantly changed also in the patients with hepatic metastases (HPI = 0.24, range: 0.11-0.38; A/V = 0.34, range: 0.12-0.61) compared with the control group. These changes were correlated with increased hepatic arterial blood flow (3.16 +/- 1.35 cm3/s) and decreased portal venous blood flow (10.39 +/- 3.81 cm3/s). These results prove the role of color Doppler US in the study of primary liver cancer and metastases. Additional examinations are nevertheless necessary to assess the diagnostic value of color Doppler US in the early detection of and discrimination between benign and malignant tumors.

Adolescent↗
PubMed1996

Parents and procedures: a randomized controlled trial.

INTRODUCTION: Previous work has shown that parents prefer to be present when their children undergo common invasive procedures, although physicians are ambivalent about parental presence. PURPOSE: To determine the effect of a parent-focused intervention on the pain and performance of the procedure, anxiety of parents and clinicians, and parental satisfaction with care. POPULATION: Children younger than 3 years old undergoing venipuncture, intravenous cannulation, or uretheral catheterization. SETTING: Pediatric emergency department of Boston City Hospital. DESIGN: Randomized controlled trial with three groups; parents present and given instructions on how to help their children; parents present, but no instructions given; and parents not present. INTERVENTION: The parents were instructed to touch, talk to, and maintain eye contact during the procedure. RESULTS: A total of 431 parents was randomized to the intervention (N = 153), present (N = 147), and not present (N = 131) groups. The groups were equivalent with respect to measured sociodemographic variables and parents' previous experience in the pediatric emergency department. No differences emerged with respect to pain (3-point scale measured by parent and clinician, and analysis of cry); performance of the procedure (number of attempts, completion of procedure by first clinician, time); clinician anxiety; or parental satisfaction with care. Parents who were present were more likely to rate the pain of the children as extreme/severe (52%) in comparison to clinicians (15%, kappa .07, poor agreement) and were significantly less anxious than parents who were not present. CONCLUSION: Overall, the intervention was not effective in reducing the pain of routine procedures. Parental presence did not negatively affect performance of the procedure or increase clinician anxiety. Parents who were present were less anxious than those who were not present. CLINICAL IMPLICATION: In general, parents have indicated that they want to be present when their children undergo procedures. The results of this study challenge the traditional belief that parental presence negatively affects our ability to successfully complete procedures. We should encourage parents who want to be present to stay during procedures.

Adult↗
PubMed1995

Career choice in one general pediatric Title VII--supported residency.

The concern that there are too few generalist physicians and too many specialists is part of the ongoing health care debate. Medical educators have been challenged at the graduate and undergraduate levels to educate more generalists. While some question the actual effect of medical education on the choice of a generalist career, others strongly express the view that a generalist curriculum influences graduates to pursue a career in primary care. Residency training programs are largely based in hospitals, and pediatric practice is largely community based. The terms educational malpractice, educational mismatch, and, most recently, educational dysjunction have been used to describe the difference between the educational and practice experience.

Boston↗
PubMed1994

Intramuscular versus oral antibiotic therapy for the prevention of meningitis and other bacterial sequelae in young, febrile children at risk for occult bacteremia.

Because studies of the treatment of children with occult bacteremia have yielded conflicting results, we compared ceftriaxone with amoxicillin for therapy. Inclusion criteria were age 3 to 36 months, temperature > or = 39 degrees C, an acute febrile illness with no focal findings or with otitis media (6/10 centers), and culture of blood. Subjects were randomly assigned to receive either ceftriaxone, 50 mg/kg intramuscularly, or amoxicillin, 20 mg/kg/dose orally for six doses. Of 6733 patients enrolled, 195 had bacteremia and 192 were evaluable: 164 Streptococcus pneumoniae, 9 Haemophilus influenzae type b, 7 Salmonella, 2 Neisseria meningitidis, and 10 other. After treatment, three patients receiving amoxicillin had the same organism isolated from their blood (two H. influenzae type b, one Salmonella) and two from the spinal fluid (two H. influenzae type b), compared with none given ceftriaxone. Probable or definite infections occurred in three children treated with ceftriaxone and six given amoxicillin (adjusted odds ratio 0.43, 95% confidence interval 0.08 to 1.82, p = 0.31). The five children with definite bacterial infections (three meningitis, one pneumonia, one sepsis) received amoxicillin (adjusted odds ratio 0.00, 95% confidence interval 0.00 to 0.52, p = 0.02). Fever persisted less often with ceftriaxone (adjusted odds ratio 0.52, 95% confidence interval 0.28 to 0.94, p = 0.04). Although the difference in total infections was not significant, ceftriaxone eradicated bacteremia, prevented significantly more definite focal bacterial complications, and was associated with less persistent fever.

Administration, Oral↗
PubMed1992

Characteristics of the interactions between acid glycosaminoglycans and proteins in normal human plasma as revealed by the behaviour of the protein-polysaccharide complexes in ultrafiltration and chromatographic procedures.

Acid glycosaminoglycans were isolated from normal human plasma: (a) following fractionation of plasma (with protease inhibitors) on Sephadex G-200; (b) by ultrafiltration through membranes with retention of molecules above 50 kDa, with and without previous addition of NaCl, Triton X-100, urea, or guanidine HCl; (c) by filtering on Ecteola-cellulose either untreated plasma or after treatment with NaCl, urea, Triton X-100, papain or NaOH. More than 95% of plasma glycosaminoglycans interact with plasma proteins to give complexes that exhibit reproducible behaviour on Sephadex G-200 and are retained by ultrafiltration membranes, which the 12-20 kDa polysaccharide chains do filter. High charge plasma glycosaminoglycans show ionic interactions with proteins, while low charge glycosaminoglycan interactions are resistant to Ecteola charged groups, to 0.5% Triton and 4 M urea, while not to 4 M guanidine HC1. Some glycosaminoglycan-protein complexes appear resistant to proteolysis, suggesting that they may originate from lymphocytes. The simple method utilized for plasma GAG measurement may represent an useful tool in clinical practice.

Blood Proteins↗