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Biomedical subjects

D Antonelli

Publications and source records attributed to D Antonelli.

At least 19 recordsLinked to original sources
PubMed2005

T cell repertoire in patients with stable scleroderma.

At onset of systemic sclerosis (SSc), T cells have been found to oligoclonally expand in the skin, presumably in response to auto-antigens, but the T cell repertoire has not been evaluated at a later stage. To determine whether a perpetuating immune response contributes to the pathogenesis of stable SSc, the T cell repertoire was analysed in patients with diffuse (d) or limited (l) SSc, and compared to patients with primary Raynaud's phenomenon (RP) or healthy volunteers (Ctrl). The T cell repertoire (total, CD4 or CD8 sorted blood T cells) was analysed by qualitative and quantitative immunoscope (14 BV families analysed) in 11 untreated dSSc and 11 untreated lSSc, 10 RP and 11 Ctrl. To better detect in vivo activated cells, repertoire analysis was also performed on sorted CD4 T cells after in vitro culture with IL-2. In parallel, 6 skin biopsies from SSc patients were analysed. After 7-8 years of disease evolution, SSc patients did not show detectable clonal T cell expansions in the skin, even after tentative expansion from the biopsy with IL-2. Total T cell, sorted CD4 and CD8 T cell repertoires from the blood of patients with SSc did not show significant perturbation as compared to patients with RP and Ctrl. After IL-2 culture for 7 days, blood CD4 T cells from the patients did not preferentially expand as compared to RP and Ctrl. These findings suggest that antigen-driven immune responses may play a lesser role in established SSc than at disease onset.

CD4-Positive T-Lymphocytes↗
PubMed2001

Synthesis and electronic properties of low-dimensional bis(benzene) vanadium reduced mesoporous niobium oxide composites.

The first bis(benzene) vanadium mesoporous niobium oxide composite was synthesized and characterized. The XRD pattern of this material shows a peak (100) centered at 45 A, identical to that of starting material. The nitrogen adsorption and desorption analyses of this material exhibit a slight decrease of BET surface area from 580 m(2) g(-1) to 467 m(2) g(-1) and a concomitant decrease in pore size and volume from 28 A and 0.500 cm(3) g(-1) to 25 A and 0.363 cm(3) g(-1), respectively. The powder EPR spectrum shows eight lines which can be assigned to (51)V from bis(benzene) vanadium as well as other resonances that can be assigned to the corresponding cation. The presence of two or more organometallic vanadium species was further confirmed by UV, (1)H-MAS NMR, and XPS methods. Broadened and shifted Nb 3/2, 5/2 peaks were also observed, providing further evidence that the mesoporous transition metal oxide framework was reduced by the organometallic. SQUID magnetometer measurements on this material show paramagnetic behavior with a small contribution of spin glass behavior. The conductivity of this material was 10(-4) ohm(-1) cm(-1), significantly greater than that measured for the analogous bis(benzene) chromium composite previously studied. Since alkali-metal reduced mesoporous niobium oxide materials are insulating, this conductivity was attributed to the low-dimensional bis-arene vanadium phase in the pores and rationalized according to the balance between the Hubbard potential and the bandwidth estimated for the relevant organometallic species. A bis-1,3,5-tri-tert-butylbenzene yttrium composite was also synthesized; however, complete loss of ligand upon reduction of the mesostructure was observed, indicating that this dopant behaves more like an alkali naphthalene reagent in its reactions with mesoporous niobium oxide than other bis(arene) complexes investigated by our group.

Journal Article↗
PubMed2001

Lead insertion by supraclavicular approach of the subclavian vein puncture.

Total occlusion of the left subclavian vein was diagnosed in a 76-year-old patient, 6 years after implantation of an ICD with VVI pacing backup. Replacement of the ICD included upgrading of the ICD system because of the presence of pacemaker syndrome when the patient was VVI paced. Insertion of an atrial lead through the ipsilateral vein system was made possible by using the supraclavicular approach of the subclavian, enabling puncturing of the left subclavian vein medially to the obstruction.

Aged↗
PubMed2001

Acute loss of capture due to flecainide acetate.

Antiarrhythmic drugs increase pacing threshold, but this is rarely of clinical significance. Administration of flecainide acetate in a 75-year-old woman with an implanted AAIR pacemaker because of sick sinus syndrome caused an abrupt rise of pacing threshold and failure of pacing. Pacing threshold returned to the normal value a few days after flecainide treatment was stopped.

Acute Disease↗
PubMed2000

Enoxaparin associated with hugh abdominal wall hematomas: a report of two cases.

Enoxaparin is a low-molecular-weight heparin used for prophylaxis against deep venous thrombosis. Indications include hip and knee replacement surgery, risk of deep venous thrombosis during abdominal surgery, and prevention of ischemic complications of unstable angina and non-Q-wave myocardial infarction. Its efficacy in the prevention of the above complications has been previously studied; however, the liberal use of enoxaparin is not without incident. Complications of enoxaparin include hemorrhage, thrombocytopenia, and local reactions. Since 1993 there have been more than 40 reports of epidural or spinal hematoma formation with the concurrent use of enoxaparin and spinal/epidural anesthesia or spinal puncture. Herein reported are two cases of abdominal wall hematomas in patients receiving prophylaxis with enoxaparin. Both patients sustained an unexplained fall in the hematocrit and abdominal pain. A CT scan confirmed the diagnosis. One patient recovered uneventfully; however, the other patient, on chronic hemodialysis, became hemodynamically unstable and hyperkalemic and sustained a fatal cardiac arrhythmia. An extensive review of the literature revealed no similar cases of abdominal wall hematomas associated with enoxaparin although other complications, including spinal and epidural hematomas, psoas hematomas, and skin necrosis have been reported. The extended use of enoxaparin as an anticoagulant requires the physician to be vigilant of these rare complications. Bleeding can occur at any site during therapy with enoxaparin. An unexplained fall in the hematocrit or blood pressure should lead to a search for a bleeding site.

Abdominal Muscles↗
PubMed1999

[Propafenone dose for emergency room conversion of paroxysmal atrial fibrillation].

Paroxysmal atrial fibrillation (AF), a frequent cause of repeated hospitalization, is effectively treated with propafenone. The time to conversion to sinus rhythm is a consideration when managing AF in the emergency room. We investigated the conversion rates of paroxysmal AF by 3 different oral propafenone (P) regimens, in terms of time to conversion. 188 patients with onset of AF within 48 hours were treated with propafenone (P): 48 received 600 mg as a first oral dose followed after 8 hrs by 150 mg (Group A); 82 received 300 mg as a first dose, followed by the same dose 3 and again 8 hrs later (B); 58 received 150 mg every 3 hrs, up to a total dose of 600 mg (C). P was stopped when sinus rhythm was achieved. Rates of conversion to sinus rhythm after 3 hrs in the 3 groups were: 46%, 41% and 26% respectively; after 8 hrs: 77%, 78% and 70%; and after 12 hrs: 81%, 84% and 76%. Treatment was discontinued in 8. There was excessive QRS widening (> 25% of the basal value) in 1 in group A, 1 in group B and 2 in group C; wide-QRS tachycardia occurred in 4 in group B. In Group A there was a higher rate of early successful conversion, with a lower incidence of side-effects than with the other regimens.

Administration, Oral↗
PubMed1999

Failure of left-sided implantable cardioverter defibrillator implantation due to absence of left brachiocephalic vein.

Implantation of an implantable cardioverter defibrillator by the transvenous approach was impossible from the left side in a patient with on absence of the left brachiocephalic vein; the left subclavian vein was connected by a large left superior intercostal vein to the accessory hemiazygos vein that joined the azygos vein; then the blood flowed into the superior vena cava. Implantation was successfully attempted using the right-sided venous access.

Aged↗
PubMed1999

Large bowel obstruction due to intrauterine device: associated pelvic inflammatory disease.

Pelvic actinomycosis associated with the use of intrauterine contraceptive devices (IUDs) can mimic pelvic malignancy. Recognizing this rare, but not uncommon complication of IUD use can spare a patient from an extensive surgical procedure. If recognized preoperatively, a simple regimen of antibiotics can be curative; however, if symptomatic, a limited surgical procedure is warranted. We present the case of a 55-year-old woman with a slow, indolent course of partial large bowel obstruction and a history of IUD use for over 20 years. A preoperative CT scan revealed a frozen pelvis mimicking a pelvic malignancy. Exploratory laparotomy revealed a firm, indurated, fibrotic reaction in the pelvis involving the uterus, adnexa, and sigmoid colon. A diverting loop colostomy was performed, and pathology revealed sulfur granules from the extracted IUD that grew Actinomyces. The patient was treated with the appropriate antibiotics, and during the takedown of the colostomy 6 months later the pelvic inflammation was completely resolved. An extensive review of the literature involving actinomycotic abscesses associated with IUD use reveals a limited number of studies reported in the general surgical literature. It behooves the general surgeon to be aware of this unusual case so that the appropriate consultation and treatment can be performed with limited morbidity to the patient.

Actinomycosis↗
PubMed1998

Insulation lead failure: is it a matter of insulation coating, venous approach, or both?

Lead insulation material and implant route have a major impact on lead reliability and durability. We compare the incidence of lead insulation failure resulting from both the venous approach and insulation type. Two hundred ninety consecutive leads were followed for a mean period of 57 +/- 30 months; leads with < 1 year follow-up were excluded. There were 116 Silicone Rubber insulated leads and 174 with polyurethane (151 Pellethane 80A and 23 Pellethane 55D) insulation; 279 leads were bipolar and 11 unipolar; 274 leads were implanted in the ventricle and 66 in the atrium. The venous route was the subclavian vein for 170 leads (58%) and the cephalic vein for 120 leads (42%). Insulation failure was diagnosed when a single sign of oversensing, undersensing, failure to capture, early pulse battery depletion, and lead impedance < 250 omega was present. Measurement of lead impedance was performed intraoperatively at implantation and during lead revision or pulse generator replacement. Lead failure caused by conductor coil fracture was not considered. There were 13 lead insulation failures, all among leads with polyurethane insulation (12 Pellethane 80A and 1 Pellethane 55D). Eleven failures (10%) occurred when the subclavian vein and 2 (3%) when the cephalic vein approach was used. The cumulative survival rate of polyurethane and silicone rubber insulated leads was 88.7% and 100%, respectively (P = 0.02); the cumulative survival rate of polyurethane insulated leads was 83.2% when the subclavian vein and 95.1% when the cephalic vein were used (P = 0.03). The mean time to polyurethane lead failure when the subclavian vein approach was used was 54 +/- 17 months and when the cephalic route was 73 +/- 4 months (P < 0.02). By multivariate analysis, the route of entry was found to be a significant variable related to polyurethane insulated lead failure (P < 0.05). At lead revision failure to capture was present in 7, oversensing in 4, and undersensing in 2 instances; impedance was < 250 omega in all cases. Pellethane 80A insulated leads are prone to insulation failure, but more when the subclavian vein is used, rather than the cephalic vein.

Aged↗
PubMed1997

Implantation of dual chamber pacemaker in a patient with persistent left superior vena cava.

A 35-year-old patient underwent permanent pacemaker implantation because of symptomatic sinus bradycardia. During the procedure, persistent left superior vena cava was found. The ventricular lead crossed the tricuspid valve only after curving the stylet to form a loop in the right atrium (RA); subsequently, the curved stylet was changed to a straight one and the lead was positioned and screwed into the right ventricular apex. The atrial lead positioning was possible when the stylet was slightly curved and the lead could reach the anterior wall of the RA. At 18 months, a follow-up revealed normal pacemaker function and stable lead position.

Adult↗
PubMed1997

Deglutition syncope associated with carotid sinus hypersensitivity.

A 78-year-old patient complained of syncope, near syncope, and dizziness when eating; complete atrioventricular block, with ventricular asystole for 3.6 seconds, was recorded on continuous electrocardiographic monitoring. Left and right carotid sinus massage produces sinus arrest and ventricular asystole lasting 6.4 and 4.8 seconds, respectively. These phenomena were prevented by atropine administration. The symptoms were completely relieved by permanent pacing, but the patient died 6 months later because of large cell undifferentiated carcinoma of the lower third of the esophagus.

Aged↗
PubMed1997

[Conservative therapy in renal carcinoma: follow-up].

Due to the increasing use of sophisticated imaging techniques, up to 30% of diagnosed renal cell carcinoma (RCC) are asymptomatic and diagnosed incidentally. Getting the cue from our personal survey of conservative renal surgery for renal cell carcinoma with a cancer specific survival of 95.5% after a mean follow up of 32.7 months, a review of the literature is illustrated: numerous studies have documented the technical success rate with this approach as well as long term disease free survival, comparable to that obtained by radical nephrectomy, in patients with unilateral, small, low stage tumors and normal opposite kidney. Patient selection is of extreme importance in case of partial resection in the presence of a normal contralateral kidney. The tumor must be < 3-4 cm, solitary, well delineated on CT, without invasion of the perinephric far or pyelocaliceal system (T1 and T2), easily resectable with at least 1 cm of healthy parenchyma. Only well informed patients who agree on a careful follow up after surgery can be candidates for kidney sparing surgery. In case of imperative surgery the follow up must be strict and personified for every single patient. Those patients who underwent a partial nephrectomy in presence of a normal contralateral kidney should be monitored with a conventional follow up monitored in order to detect an eventual local recurrence: 12 monthly ultrasonography and contrast enhanced CT scan alternately every 6 months for the first five years after surgery and then lifelong once a year by echography and/or CT scan.

Adult↗
PubMed1997

Variation in nocturnal urinary excretion of melatonin in a group of patients older than 55 years suffering from urogenital tract disorders.

Melatonin (MLT) is directly or indirectly related to cell growth (both of normal and neoplastic cells), to the immune system stimulation and to the endocrine system modulation. This controlled study was carried out to evaluate urinary excretion of MLT in patients suffering from urogenital tract disorders. Eighty-one patients affected by urogenital disorders were divided in two groups (neoplastic and non-neoplastic) and urinary excretion of MLT was evaluated. Mean diurnal (from 8 a.m. to p.m.) urinary excretion of MLT was 4.97 + 6.08 pg/12 h in non-oncologic patients and 4.82 + 6.21 pg/12 h in oncologic patients (p = 0.50). Mean nocturnal (from 8 p.m. at 8 a.m.) urinary excretion of MLT was 11.97 + 9.34 pg/12 h in non-oncologic patients while in oncologic patients it was 7.86 + 8.95 pg/12 h. Statistically significant variation in nocturnal urinary excretion of melatonin was observed in oncologic patients (p = 0.022) versus non oncologic patients.

Aged↗
PubMed1996

Is laparoscopy a worthy method to treat varicocele? Comparison between 160 cases of two-port laparoscopic and 120 cases of open inguinal spermatic vein ligation.

Because it is still a puzzling debate whether ligation of a unilateral varicose spermatic vein is worth performing by laparoscopy, even with the two-port technique, we conducted a study in which 280 patients with palpable left varicoceles were treated with spermatic vein ligation either by open surgery (120 patients) or by laparoscopy (160 patients). The inclusion criteria were the same for each group, and the two groups were homogeneous in preoperative clinical features and patient characteristics. The clinical outcomes were compared 6 months after surgery, and the costs of each treatment were analyzed. The procedures showed the same effectiveness and intraoperative safety. Open surgery scored a shorter operating time, whereas hospitalization was significantly shorter in the laparoscopic group. Postoperative complications occurred more frequently in the open surgery than in the laparoscopic group (7.5% and 0.6%, respectively). Of the patients treated, 197 were eligible for seminal analysis: 82 and 115 in the open surgery and laparoscopic groups, respectively. Significant improvement in seminal analysis was recorded in both groups, whereas no difference was found between the groups. Laparoscopy costs about 60% more than open surgery. It can thus be concluded that laparoscopy is not a worthy method to treat unilateral varicocele.

Adolescent↗
PubMed1996

[T1G3 of the bladder: our experience].

From June 1991 to June 1995 we treated 20 patients affected by T1 G3 TCC of the bladder, 18 men and 2 women, with a mean age of 65.1 years (46-71). In 11 patients the disease was monofocal, with diameter of the tumor under 3.5 cms; in 5 patients monofocal with diameter of the tumor over 3.5 cms; in 1 patient multifocal and in 3 patients complex (mono or multifocal associated with CIS). The 11 patients with monofocal disease under 3.5 cms were treated with TUR-B, the other 9 (all males) were submitted to radical cystectomy with OINB diversion as first choice treatment. The mean follow up (all patients) was 3.2 years (6 months-14 years). Out of the patients of the former group only 3 did not show any relapse, the other 8 showed multiple relapses or metachronous tumors: 5 were treated with TUR-B+BCG, 3 were cystectomized. The patients submitted to cystectomy as first choice treatment did not show any progression of the disease after a mean follow-up of 19.8 months.

Aged↗
PubMed1996

[100 orthotopic neobladders in men after cystectomy: a 5-year experience].

Urethral bladder substitution is traditionally suggested to good prognosis cystectomized patients. In our series this diversion was chosen for all but the salvage cystectomized men. Between the 1st of February 1991 and the 30th of April 1996, one hundred consecutive men underwent lower urinary tract reconstruction after radical cystoprostatectomy for bladder cancer. An orthotopic ileal neobladder was constructed (in 84 cases according to Kock's technique and in 16 to Studer's technique). Total early complication rate was 29% (29/100), including one perioperative death due to sepsis (mortality rate 1%). 13 patients required surgery (6 retroperitoneal hematomas, 2 wound dehiscences, 1 urinary fistula, 1 lymphocele, 1 rectal-neobladder fistula, 1 rectal-cutaneous fistula, 1 necrosis of the terminal ureter). The late complication rate was 19% (19/100); in 8 cases reparative surgery was required (1 mechanical ileus, 2 bladder neck stenoses, 3 stenoses of the ureteral anastomosis, 2 laparoceles). Four patients were lost at the follow-up; out of the 96 remaining patients only 85 were evaluable for continence: continence during the day was achieved in a period between there to six months in 78 patients (91.7%); night continence was achieved with planned awakenings in 60 patients (70.5%). Eight patients recovered potency, another 7 had successful intercourses after PGE1 intracavernous injection. Renal function based on creatinine value was mildly impaired in 5/78 evaluable patients (6.4%) (peak creatinine 2.8 mg%). In 29 patients tumour progression was observed (29%): 9 pelvic and 20 metastatic. Among the latter 2 urethral recurrences were observed (2%). Twenty-four patients died for metastatic cancer, one for primitive lung cancer, one patient for postoperative septic shock. Adjuvant chemotherapy was administered in 11 patients without complication with an indwelling catheter in the neobladder to avoid drug reabsorption. Four patients showed complete response (2 are alive after a mean of 12 months), 6 were non responders and 1 had a partial response. In our series the ileal neobladder is a feasible method of urinary diversion when urethral cancer involvement is ruled out. Early and late complications are proportionally decreasing with experience and overall continence is satisfactory. The fate of the neobladder depends on both the technique and patient's compliance. Only educated patients can cope successfully with neobladder diversion without major complications. All the patients operated for non salvage cystectomy deserve to be diverted with a continent urethral bladder substitution.

Adenocarcinoma↗