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Biomedical subjects

G Napoli

Publications and source records attributed to G Napoli.

At least 19 recordsLinked to original sources
PubMed2005

Reexamination of the Helfrich-Hurault effect in smectic-A liquid crystals.

The Helfrich-Hurault effect is a phase transition that occurs in samples of cholesteric or smectic liquid crystals subject to external electric or magnetic fields. In this paper we analyze the Helfrich-Hurault effect of smectic-A liquid crystals in an electrostatic field taking into account the complete electromechanical coupling. A comparison is made with the results already obtained for the partially coupled case where one takes into account only the effect of the field on the crystal configuration and considering that field unaffected.

Journal Article↗
PubMed2005

The dilemma of the negative skin test reactors with a history of venom anaphylaxis: will this always be the case?

The loss of sensitization over time, the involvement of a different pathogenetic mechanism and the poor sensitivity of diagnostic tests have been included among the causes of a non IgE-mediated anaphylaxis triggered by an insect sting. To provide further insight into this topic we describe the case of a patient suffering from urticaria pigmentosa, anaphylactic shock due to a Vespid sting and monosensitive to Polistes dominulus venom, who was previous diagnosed with non-IgE mediated insect sting anaphylaxis in subjects with urticaria pigmentosa. Therefore ultra-rush specific immunotherapy using an acqueous Polistes dominulus venom extract was performed over two mornings until a total dose of 100mcg was reached without any side effects. Presently the patient is undergoing maintenance therapy with a depot Polistes dominulus venom extract at 4-weekly intervals and is free of side effects. In conclusion, despite the high cross-reactivity among the venoms of the various species of Polistes, recent evidence of a selective specificity unique to European Polistes allergens raises the problem of the need to make the American Polistes venom as well as that of Polistes dominulus (a very common insect in Europe) available both for diagnostic and therapeutic purposes. Besides the fact that the presence of urticaria pigmentosa alone could have explained the anaphylactic reaction to the aspecific stimulation triggered by the venom, this case history also demonstrates that omitting to perform skin tests for Polistes dominulus venom would have led to the same misdiagnosis of non IgE-mediated anaphylaxis and served only to further delay commencing specific immunotherapy.

Adult↗
PubMed2003

European hornet (Vespa crabro) sting: a new risk factor for life-threatening reaction in hymenoptera allergic patients?

BACKGROUND: Severity of a previous reaction, adult age, male gender and honeybee sting are risk factors for severe systemic reactions after hymenoptera stings. The aim of the study was to assess the association between the Vespa crabro sting and severe systemic reactions. METHODS: One hundred fifty seven hymenoptera allergic patients with a positive case history for systemic reactions were selected on the basis of unequivocal identification of the stinging insect. In 97 patients the culprit insect was Vespula spp., in 35 was Vespa crabro in the remaining 25 patients was Apis mellifera. The relative risk for a life-threatening reactions after a sting was evaluated for each hymenoptera species. RESULTS: While the percentage of life-threatening reactions was similar both in Apis mellifera (24%) and in Vespula spp. Allergic patients groups (27.8%), a very high prevalence (81.2%) was documented in Vespa crabro allergic patients group. The relative risk for life-threatening reactions after a Vespa crabro sting was about three times higher (RR = 2.74--CI 95% 1.93-3.89--R < 0.0001) than it was for a honeybee or yellow jacket sting. The increase of the risk for life-threatening reactions after a Vespa crabro sting was independent from the age of patients. CONCLUSION: Vespa crabro sting seems to be a new risk factor for life-threatening reactions after hymenoptera sting.

Adult↗
PubMed2002

Benzydamine: an alternative nonsteroidal anti-inflammatory drug in patients with nimesulide-induced urticaria.

BACKGROUND: Cutaneous adverse reactions to nonsteroidal anti-inflammatory drugs (NSAIDs), in particular urticaria/angiedema syndrome, represent a frequent problem in clinical practice. To date laboratory tests for the diagnosis of these adverse reactions are not available. A patient with an adverse drug reaction to NSAIDs needs an alternative drug to assume if necessary. Nimesulide is a highly prescribed nonsteroidal anti-inflammatory drug (NSAID) world-wide. It is also described as one of the most tolerated NSAID. In this paper we present data on the tolerability of benzydamine in nimesulide-sensitive patients. PATIENTS AND METHODS: One hundred and thirty-seven patients with nimesulide-induced urticaria were submitted to a single-blind, placebo-controlled peroral challenge with increasing doses of benzydamine. RESULTS: One hundred and thirty-four out of 137 (98%) patients tolerated benzydamine without adverse effects, only three (2%) experienced immediate systemic urticaria (1 at the first dose and 2 at the second dose). CONCLUSION: Benzydamine is a well tolerated drug in patients with nimesulide-induced urticaria and it may represent a valid alternative NSAID in nimesulide-sensitive patients.

Acetaminophen↗
PubMed2001

Usefulness of transesophageal echocardiographic monitoring to improve the outcome of stent-graft treatment of thoracic aortic aneurysms.

The stent-graft procedure is becoming an alternative to surgery for treatment of many diseases of the descending thoracic aorta. This study evaluated the role of transesophageal echocardiography (TEE), used in combination with fluoroscopy and angiography, in monitoring the outcome of stent-graft placement. Twenty-two consecutive patients were submitted to stent-graft positioning in the descending aorta for various pathologies (7 patients had type B aortic dissections, 6 had thoracic aneurysms, 2 had thoraco-abdominal aneurysms, and 7 had post-traumatic aortic aneurysms). Before stent-graft deployment, TEE changed the proximal site of stent positioning initially identified by angiography in 33% of patients (5 of 15) with aortic aneurysms because of calcifications or atheromas that could interfere with stent adhesion to the aortic wall and that were not seen on angiography. In 28% of patients (2 of 7) with aortic dissection, TEE showed the guidewire in the false lumen, allowing an immediate repositioning. After stent-graft deployment, color Doppler TEE showed a perigraft leak in 7 patients, whereas angiography detected a perigraft leak in only 2 patients (p = 0.02). In 4 of these patients, further balloon expansions resulted in resolution of the leak. In the remaining 3 patients, additional stent-graft positioning was necessary. Considering the total patient cohort, TEE yielded relevant information, resulting in procedure changes in 59% (13 of 22). In conclusion, TEE provided additional information with respect to angiography in all phases of stent-graft treatment, improving immediate outcome and reducing complications.

Adult↗
PubMed2001

The incremental challenge test in the diagnosis of adverse reactions to local anesthetics.

OBJECTIVE: The aim of this study was to assess the reliability of a diagnostic protocol, the incremental challenge test (ICT), for patients with and without a history of adverse reactions to local anesthetics (LAs) or other drugs, to select an LA that could be safely used. STUDY DESIGN: The ICT was performed on 432 subjects, 314 female and 118 male. Four hundred thirty-two challenges were carried out with LAs that were free of adrenaline and preservatives. Chi-square analysis was performed to evaluate the existence of different predispositions to ICT positivity among subjects of the 4 categories studied. RESULTS: Four hundred fifteen tests were completed with no clinical events occurring. The analysis did not show any significant difference (chi-square = 6.17; P >.05). CONCLUSIONS: Our results confirm that immunoglobulin E-mediated reactions to LAs are uncommon and that the ICT offers safety and specificity in diagnosing adverse reactions to LAs, allowing for the selection of a safe and reliable LA.

Adolescent↗
PubMed2001

[Non-surgical treatment of aortic aneurysms and dissections: indications, strategies and outcome].

PURPOSE: The endovascular treatment of the thoracic aorta is an effective alternative to open surgical repair and offers a therapeutic option even to patients at high risk for surgery. Our experience in the treatment of different diseases of descending thoracic aorta is reported. MATERIAL AND METHODS: Between July 1997 and January 2001, 50 patients were selected for endovascular treatment: 36/50 patients presented high risk for conventional surgery. Six patients presented clinical and imaging features suggesting impending rupture and were treated on emergency basis. The stent-graft prosthesis was individually manufactured or selected on the basis of spiral CT or MRI measurements. RESULTS: Endovascular stent positioning and deployment was technically successful in 49 cases. In one patient the tortuosity of the aortic arch prevented graft deployment. Complete aneurysm exclusion was achieved in 48 cases as assessed by post-procedure angiography and TEE. One proximal endoleak was noted and surgical conversion was performed 40 days later. There were no intraoperative mortality or complications. One patient presented extension of dissection at the 8th postoperative day and required of surgical repair. CT scan showed an endoleak in 4 cases that sealed spontaneously in three cases while the fourth case was treated by graft extension. In the long term two secondary endoleak were observed (12 and 24 months after the procedure). CONCLUSIONS: Endovascular stent-graft repair provides a less invasive opportunity to patients affected by thoracic aortic disease. Careful cases selection is the first postulate for the efficacy and safety of the procedure.

Aortic Dissection↗
PubMed2000

Evolution of aortic dissection after surgical repair.

Patients after aortic dissection repair still have long-term unfavorable prognosis and need careful monitoring. The purpose of this study was to analyze the evolution of aortic dissection after surgical repair in correlation to anatomic changes emerging from systematic magnetic resonance imaging (MRI) follow-up. Between January 1992 and June 1998, 70 patients underwent surgery for type A aortic dissection. Fifty-eight patients were discharged from the hospital (17% operative mortality) and were followed by serial MRI for 12 to 90 months after surgery. In all, 436 postoperative MRI examinations were analyzed. In 13 patients (22.5%) no residual intimal flap was identified, whereas 45 patients (77.5%) presented with distal dissection, with a partial thrombosis of the false lumen in 24. The yearly aortic growth rate was maximum in the descending aortic segment (0.37 +/- 0.43 cm) and was significantly higher in the absence of thrombus in the false lumen (0.56 +/- 0.57 cm) (p <0.05). There were 4 sudden deaths, with documented aortic rupture in 2. Sixteen patients underwent reoperation for expanding aortic diameter. In all but 1 patient, a residual dissection was present (in 13 without any thrombosis of the false lumen). Close MRI follow-up in patients after dissection surgical repair can identify the progression of aortic pathology, providing effective prevention of aortic rupture and timely reoperation. Thrombosis of the false lumen appears to be a protective factor against aortic dilation.

Adult↗
PubMed2000

Primary endoleakage in endovascular treatment of the thoracic aorta: importance of intraoperative transesophageal echocardiography.

OBJECTIVES: Endovascular treatment of the thoracic aorta has developed as an efficacious alternative to open surgical repair. However, despite the high primary success rate, perigraft leakage constitutes the major concern in long-term follow-up. Endoleaks are widely reported both in abdominal and thoracic endovascular series and are usually identified by intraoperative angiography. Transesophageal echocardiography is a sensitive imaging technique in the evaluation of aortic diseases, widely used to monitor cardiac surgery. The aim of this study was to evaluate the efficacy of transesophageal echocardiography in leakage detection during endovascular stent procedures of the thoracic aorta. METHODS: Intraoperative transesophageal echocardiography was used in conjunction with angiography in 25 patients subjected to endovascular stent treatment of the descending thoracic aorta. Spiral computed tomographic scanning was performed before discharge and 3, 6, and 12 months after treatment. RESULTS: Information from transesophageal echocardiography was relevant in the selection of the landing zone in 62% of cases. In 8 patients, transesophageal echocardiography with color Doppler sonography showed a perigraft leak, 6 of which were not visible on angiography, suggesting the need for further balloon expansion or graft extension. Postoperative computed tomographic scanning in the 25 patients showed 1 endoleak, which sealed spontaneously. At 3 months, computed tomographic examination confirmed the absence of perigraft leakage in all patients. CONCLUSIONS: During implantation of a stent-graft in the descending thoracic aorta, transesophageal echocardiography provides information in addition to that provided by angiography, improving immediate and late procedural results.

Adult↗
PubMed2000

Phase I/II study of gemcitabine plus vinorelbine as first-line chemotherapy of non-small-cell lung cancer.

PURPOSE: To determine the maximum-tolerated dose of gemcitabine when combined with a fixed dose of vinorelbine in the treatment of non-small-cell lung cancer (NSCLC) and to evaluate in a phase II trial the activity of this combination. PATIENTS AND METHODS: Sixty-eight patients with stage IIIB/IV NSCLC were treated with vinorelbine at fixed dose of 30 mg/m(2) intravenously and gemcitabine at increasing dose levels from 800 to 1,500 mg/m(2) intravenously on days 1 and 8 every 3 weeks. RESULTS: In phase I, dose-limiting toxicity occurred at the dosage of 1,500 mg/m(2) gemcitabine, with three of five patients developing grade 4 thrombocytopenia. In phase II, with gemcitabine at 1,200 mg/m(2), 19 (36%) of 52 assessable patients responded. Objective response was observed in 11 (39%) of 28 patients with stage IIIB disease and in eight (33%) of 24 patients with stage IV. The median time to progression was 29 weeks (range, 2 to 41 weeks; 35 weeks and 16 weeks for stages IIIB and IV, respectively), and median survival was 54 weeks (range, 2 to 84+ weeks; 63 weeks and 42 weeks for stages IIIB and IV, respectively). One-year survival was 64% for patients with stage IIIB disease and 29% for those with stage IV. Clinical benefit response was observed in 29 (59%) of 49 assessable patients. Grade 4 leukopenia and thrombocytopenia were uncommon (6% and 8% of cases, respectively); however, grade 3/4 leukothrombocytopenia occurred more frequently in patients aged more than 70 years (52% and 24%, respectively). CONCLUSION: The combination of vinorelbine and gemcitabine is effective and tolerable in the treatment of NSCLC, thus deserving randomized trials with cisplatin combination regimens.

Adult↗
PubMed2000

Magnetic resonance imaging evaluation of aortic elastic properties as early expression of Marfan syndrome.

In Marfan syndrome, early identification and treatment of aortic involvement could improve prognosis, but clinical diagnosis may be difficult at a young age, before aortic dilation occurs. The aim of this study was to evaluate biomechanical aortic properties in Marfan patients and in their relatives to identify an early index of aortic involvement. A magnetic resonance imaging (MRI) morphologic and functional study of the thoracic aorta was performed in 20 Marfan patients, 15 family members, and 14 healthy volunteers as a control group. The aorta was imaged in the oblique sagittal plane by spin-echo sequence. A high-resolution gradient-echo sequence was then applied in the axial plane at the level of ascending supravalvular aorta to evaluate aortic distensibility. Aortic distensibility (mm Hg(-1) was significantly different in the three groups (ANOVA, p = 0.0001). Aortic distensibility was sensibly reduced in Marfan patients (0.0085 +/- 0.006 vs. 0.025 +/- 0.006 control group, p < 0.05). No significant correlation was found between aortic area and distensibility. Aortic distensibility was reduced also in family members (0.016 +/- 0.011 vs. 0.025 +/- 0.006 control group, p < 0.05). Among them, 4 subjects showed aortic diameters to the upper limit of the normal range, whereas the other 11 presented normal aortic diameters. Intraobserver and interobserver reproducibility for diastolic measurement was 1.2% and 0.4%, respectively, and 1.1% and 0.3%, respectively, for systolic measurement. MRI is an accurate technique in detecting abnormal aortic elastic properties in Marfan patients. Abnormal ascending aorta distensibility may constitute an index of early aortic involvement before dilation occurs.

Adolescent↗
PubMed1999

[Endovascular treatment in diseases of the thoracic aorta].

PURPOSE: To determine whether endovascular treatment of thoracic aorta conditions can be an effective alternative approach to surgical repair. MATERIAL AND METHODS: July 1997 to February 1999, eighteen patients (16 men and 2 women; 58.6 +/- 14.8 years) presenting with different kinds of descending aorta conditions were selected for the endovascular treatment. All patients exhibited severe comorbid pulmonary and/or cardiovascular medical conditions which increased surgical risk. All implants were performed in the operating room under fluoroscopic and TEE guidance. Clinical and imaging follow-up was performed 1, 3, 6 and 12 months later. RESULTS: The endovascular treatment was successful in 17 cases. No deaths or major complications occurred. No leakage was evident at post-procedure angiography. The patients were discharged after 6 +/- 4 days. MRI or CT study performed before hospital discharge showed aneurysms exclusion in 16 patients. In the four cases of dissection, thrombosis of the false lumen was evident since the first follow-up study. In the group of patients (11 cases) with 6 months follow-up, the diameters of stented aortic segments decreased. No late leakage was observed and thrombosis was complete in all cases. DISCUSSION: The natural history of aortic aneurysms and dissection is progressive toward dilation and aortic rupture. Surgery of descending thoracic aorta is burdened with a mortality of 8-12% in elective cases and over 50% in emergency cases or aortic dissection. The endovascular treatment of aortic conditions was introduced in clinical practice in 1991 and literature data show that it is effective, with lower mortality and morbidity rates than surgical treatment. CONCLUSION: Our results stress the feasibility and effectiveness of endovascular procedure in the treatment of complex thoracic aorta conditions even in high risk patients. Thus, endovascular treatment of thoracic aorta can be considered an effective alternative approach to conventional surgery.

Adult↗
PubMed1998

Evolution of post-traumatic aortic aneurysm in the subacute phase: magnetic resonance imaging follow-up as a support of the surgical timing.

OBJECTIVES: A recent surgical series documented that in traumatic aortic rupture (TAR) a surgical repair postponed to the treatment of associated lesions reduced operative and overall mortality. Nevertheless some isolated cases may develop to free rupture. Until now, no imaging follow-up studies of post-traumatic aortic lesions have been reported in the early stage. The aim of this study is to analyze the behaviour of traumatic aortic ruptures in the subacute phase, in order to detect the morphological characteristics of unstable post-traumatic aneurysms. METHODS: Twenty-five consecutive patients affected by traumatic aortic rupture (one intimal hemorrhage, 19 partial lesions and five circumferential lesions) were admitted to the department of cardiac surgery. Magnetic resonance imaging (MRI) was the imaging method used to confirm the diagnosis. No one was operated on during the acute phase. All patients were treated with beta-blockers and vasodilators as well as limited fluid administration. Delayed surgery was carried out in 18 patients at 243 days (+/-127), after the resolution of associated lesions. A scheduled MRI follow-up was performed at 7, 15 and 30 days and immediately before the operation. The parameters examined were increase of post-traumatic aneurysm, increase of periaortic hematoma and modification of the thoracic associated lesions. RESULTS: At 30 days a 3.0 +/- 3.7 mm median increase of the aneurysm was observed, while in the subsequent period the lesions became substantially stable, resulting in a 4.4 +/- 3.6 mm increment at the end of the follow-up. The circumferential lesions presented a higher increment with respect to the partial lesions. In three cases an augmentation of 6, 7 and 12 mm was detected and surgical repair was anticipated. In 13 cases a periadventitial hematoma surrounding the aortic aneurysm decreased through the time. One case of intimal hemorrhage healed spontaneously, with no aneurysm formation. Thoracic associated lesions (pleural and pericardial effusions, rib fractures, lung focal contusions and two cases of ARDS) resolved at 30-60 days. CONCLUSIONS: Despite common knowledge, considering TAR highly evolutive in the acute and subacute phase, this study demonstrated that this pathological entity is relatively stable if a proper pharmacological treatment is administrated. MRI follow-up is recommended in order to detect isolated cases of unstable aneurysm.

Aorta, Thoracic↗