PubMed Health⌕ Search

Biomedical subjects

L Ferrante

Publications and source records attributed to L Ferrante.

At least 37 records · Page 2Linked to original sources

Twenty-four hour heart period variability in systemic sclerosis.

OBJECTIVE: In patients with systemic sclerosis (SSc), an autonomic dysfunction has been implicated in the pathogenesis of Raynaud's phenomenon and gastrointestinal symptoms. To evaluate cardiovascular autonomic function we analyzed the heart rate variability (HRV) on 24 h electrocardiogram recordings. METHODS: In 50 patients diagnosed with SSc and 24 control subjects HRV was analyzed for both frequency and time domain. RESULTS: Frequency domain analysis showed reduction of low frequency and high frequency values in the patients with SSc compared to controls (5.52 +/- 0.74 vs 6.04 +/- 0.78 In(ms2), p = 0.007; and 4.17 +/- 0.97 vs 4.74 +/- 0.97 In(ms2), p = 0.021, respectively). Analysis in time domain showed no significant differences in any variable between groups. There were no significant differences between the diffuse and the limited form of SSc. Number of ventricular ectopic beats, prevalence of frequent ventricular ectopy, and supraventricular tachycardia episodes were increased in the patients with SSc compared to controls. CONCLUSION: Spectral analysis of heart period variability suggests cardiovascular autonomic dysfunction in patients with SSc. Better understanding of this complication could help delineate new strategies for the treatment of SSc.

Adult↗

On-line solid-phase extraction of ceftazidime in serum and determination by high-performance liquid chromatography.

A column-switching high-performance liquid chromatographic assay is described for the determination of ceftazidime (a third-generation cephalosporin) in human serum. The method does not require prior sample pretreatment. Serum is directly injected in a first chromatographic column for sample clean-up and extraction. Thereafter, using an on-line column-switching system, the drug is quantitatively transferred and separated on a second, analytical column followed by determination using ultraviolet absorption at 258 nm. The technique allows direct, rapid, precise, and simple determination of ceftazidime in serum over the range of 1-250 micrograms/ml using 12.5 microliters of serum. This method was applied to study the pharmacokinetics of the drug in patients undergoing vascular surgery.

Ceftazidime↗

Pediatric cystic meningioma: report of three cases.

Three cases of pediatric cystic meningioma are reported. In a review of the literature the authors stress the importance and difficulty of accurate preoperative diagnosis. Cystic meningioma in pediatric patients differs from that in adults in the following respects: higher incidence, predilection for males, shorter clinical history, less specific neuroradiological diagnosis, frequent absence of a dural attachment, prevalence of Nauta type II cystic meningioma, and high incidence of the fibroblastic histotype.

Adolescent↗

Glossopharyngeal neuralgia with cardiac syncope.

Glossopharyngeal Neuralgia is an uncommon craniofacial pain syndrome that is occasionally associated with cardiac syncope. Involvement of the glossopharyngeal nerve may be painless or may be marked by true episodic neuralgia, and this justifies the term neuralgia reported here. We present 5 cases of this uncommon syndrome, of a total of 15 observed cases of glossopharyngeal neuralgia, successfully treated by section of the rootlets of Cranial Nerves IX and X or by microvascular decompression in the posterior cranial fossa. We also analyze the relevant literature and discuss the pathogenesis and treatment of the syndrome.

Cranial Fossa, Posterior↗

Intracranial meningiomas in the 9th decade of life: a retrospective study of 17 surgical cases.

The general availability of cerebral computed tomographic and magnetic resonance imaging scans makes the observation of symptomatic intracranial meningiomas in very elderly patients (aged 80 yr or more) relatively frequent. A few authors have reported on patients who have undergone surgery for intracranial meningiomas in their 9th decade of life, without providing indications regarding the surgical criteria and the prognostic factors. We report on a series of 17 patients who have received surgery for intracranial meningiomas in their 9th decade of life, with the goal of determining some surgical criteria for general physicians and neurosurgeons. Patients with severe systemic disease and definite functional limitations (American Society of Anesthesiology Class III) had a major postoperative morbidity (P = 0.020) and mortality (P = 0.005), especially if they scored low (< 70) on the preoperative Karnofsky Rating Scale (P = 0.010). The risk of postoperative morbidity was higher when the maximum diameter of the tumor was > 5 cm (P = 0.031).

Aged↗

[Planar determination of the aortic valve area with transesophageal echocardiography with multiplanar probe in patients with aortic stenosis and insufficiency. Comparison with transthoracic Doppler echocardiography].

BACKGROUND: The simple determination of transaortic pressure gradient does not accurately assess the severity of an aortic valve stenosis. Thus, estimating the aortic valve area (AVA) is vital for clinical decision-making. Cardiac catheterization has been considered the "gold-standard" for the quantification of the stenotic valve area, but this technique may underestimate the actual valve area when aortic regurgitation is associated. Doppler transthoracic echocardiography (TTE) with the continuity equation method is usually employed for AVA estimation. Recently, in pure aortic stenosis, transesophageal echocardiography (TEE) has provided AVA values well-correlated to hemodynamic invasive results. METHODS: In this study, we correlated AVA values by TTE and multiplane TEE in 18 patients with combined aortic valve stenosis and regurgitation. RESULTS: The mean values of AVA by TEE and TTE were 0.74 +/- 0.12 and 0.68 +/- 0.55 cm2, respectively (p = NS). TEE-derived AVA correlated well to TTE-derived AVA (r = 0.816; p < 0.0001). Critical aortic stenosis was predicted by TEE with 100% sensitivity and specificity. Total time of examination was significantly longer for TTE (p < 0.00001). CONCLUSIONS: In conclusion, direct planimetry by multiplane TEE is a reliable method for AVA determination in aortic stenoinsufficiency. For this purpose, when the technical quality of TTE study is poor or when the patient is critically ill and does not tolerate a longer lasting TTE, multiplane TEE should be considered.

Adult↗

A Bayesian approach to drug disposition evaluation: application to teicoplanin.

We suggest a Bayesian method in order to evaluate the disposition kinetics of the drug plasma concentrations after intravenous (i.v.) and/or after extravascular administration of the drug in the same subject pooled with information obtained taking into account previous pharmacokinetics of the drug. This approach was applied to the investigation of teicoplanin pharmacokinetics after 200 mg i.v. administration to 10 healthy subjects.

Adult↗

Spinal cord ischemia diagnosed by MRI. Case report and review of the literature.

The purpose of this paper is to report a case of medullary ischemia diagnosed by MRI and to determine any MRI characteristics that may be useful for the diagnosis in the light of the published data. The patient was a 60 year-old male with hypertension and diabetes, referred to us for flaccid paraparesis and sphincter disorders of acute onset. Physical examination revealed, beside flaccid paraparesis, both superficial and deep hypoesthesia at L1 level and greater on the right. MRI showed a small area of signal hyperintensity on T2 weighted images and in proton density localized in the posterior part of the spinal cord at the level of T12 body. The patient was treated with oral antidiabetic, antiaggregant and antihypertensive drugs as well as neuromotor rehabilitation, and his clinical conditions improved; a control MRI, six months later, showed disappearance of the previous finding and only mild medullary atrophy at the level of the lesion. Medullary ischemia has been observed in a variety of pathological conditions (inflammatory, neoplastic, traumatic degenerative and iatrogenic), and most frequently involves the dorsal portion of the spinal cord. Four clinical-pathological manifestations of medullary ischemia have been described: infarction from occlusion of the anterior spinal artery; "patchy" or "lacunae infarction"; "transverse ischemic infarction"; selective ischemia in the regions of the posterior spinal arteries. A review of the literature yielded 61 cases of spinal ischemia diagnosed by MRI for a total number of 80 MRI scans, 12 of which were long-term controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗

Crossed aphasia. An update.

The aim of this article is to present an update of a rare but interesting problem: "crossed aphasia". This term indicates the presence of aphasia after unilateral cerebral lesion of the hemisphere ipsilateral to the patient's dominant hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and neurophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder.

Aged↗

Fourth ventricle ependymomas. A study of 20 cases with survival analysis.

Twenty patients with fourth ventricle ependymoma were treated surgically at our Neurosurgery Division between January 1976 and December 1990. Ependymoblastomas and mixed gliomas operated on in the same period have not been considered. A statistical analysis of our cases and a review of the largest published series show that favourable prognostic factors are: age over 16, post-operative radiotherapy to the posterior cranial fossa and a good Karnofsky performance status (KPS) after operation. The 5-year survival rate of patients under 16 was 20%, in comparison with 60% of adults (p = 0.013). Post-operative radiotherapy to the posterior cranial fossa improved the survival markedly (5-year survival rate 68%, versus 18% without treatment; p = 0.011). The differences of survival are also significant according to a multivariate analysis (p = 0.038). Patients with a post-operative KPS over 70 had a 5-year survival rate of 61% as against 17% of the group with a worse clinical condition (p = 0.032); the multivariate analysis confirmed also that this difference was significant (p = 0.046). Pre-operative symptoms and signs, and KPS, histological grade and extent of surgical removal seem to influence the prognosis, even if the differences of survival are not statistically significant. The statistical relevance of postoperative residual tumour on CT or MRI was brought out on multivariate analysis (p = 0.044).

Adolescent↗

The role of intraoperative ultrasound imaging in the surgical removal of intramedullary cavernous angiomas.

Five intramedullary cavernous angiomas were surgically removed after being localized by intraoperative ultrasound imaging. Two patients were men, and three were women; in three patients, the symptoms had an acute onset, whereas in the other two, it was gradual. The vascular malformation was localized in the dorsal tract in three patients and in the cervical tract in two. Intraoperative ultrasound imaging visualized the lesion, which appeared hyperechogenous in all cases, and showed its relationship with the surrounding anatomical structures. Surgical removal was always total and was confirmed by both intraoperative echography and postoperative magnetic resonance imaging. In our experience, intraoperative ultrasound imaging was useful for localizing intramedullary cavernous angiomas, especially in cases where the lesion did not appear on the posterior surface of the spinal cord. In this way, it was possible to limit posterior myelotomy and confirm radical tumor removal intraoperatively.

Adult↗

A stochastic model for cell debris in flow cytometry.

An important problem in analyzing flow cytometry DNA measurements, especially for tumor samples, is the presence of background noise, mainly resulting from cellular debris. Several models have been proposed for subtracting this contribution from DNA content histograms. In the present paper we propose a model for background debris distribution based on a specific mechanism for the DNA fragmentation process of the cell nucleus. In particular, we suggest that the fragmentation is more likely to occur in the sites which are closer to the end points of the DNA chain. This accounts for the observed higher frequency of small-sized fragments in experimental DNA distribution. The proposed model depends on two parameters describing the intensity and the shape of the background. It has been successfully validated against four series of experimental data of DNA distribution with increasing level of background.

Cell Fractionation↗

Non-traumatic brain abscess.

Between 1953 and 1989 eighty cases of non-traumatic brain abscess were treated in our department. We have re-examined the clinical and neuroradiological features of this pathological process and present our therapeutic approach and results. We believe that the optimal treatment for brain abscess consists of surgical removal. The prognosis for these lesions has undergone a marked improvement over the last two decades in response to neuroradiological, microbiological and surgical advances. The most influential prognostic factor seems to be preoperative clinical status.

Adolescent↗

Management of intramedullary tumours in children.

Clinical presentation, diagnosis, surgical technique and results of 25 cases of intramedullary tumours in patients under 16 years of age are analyzed. Pre-operative spinal deformity was present in 9 patients. Surgery was performed in all. After multilaminectomy with preservation of the intervertebral joints, total removal of the lesion was achieved in 11 patients and subtotal removal in 14 others. After surgery, external immobilization lasting an average period of 5 years was instituted in all patients. Postoperative radiation therapy was performed in 11 cases (5 "high grade" astrocytomas, 5 ependymomas, 1 glioblastoma). There were 11 recurrences: 4 of which (2 ependymomas and 2 "low grade" astrocytomas) were treated surgically, 7 (5 "high grade" astrocytomas, 1 glioblastoma, 1 oligodendroglioma) with palliative radiation treatment. Six patients eventually developed postlaminectomy spinal deformities as diagnosed roentgenographically 6 to 50 months postoperatively. Of the 16 patients still alive, 7 did not present relevant neurological deficit, 1 presented a monoparesis, while the other 8 presented invalidating deficits. Surgical treatment did not differ from that employed in the intramedullary tumours in the adult: radical resection is indeed the optimal therapeutic origin. The risk of radiation therapy are greater in children: it is crucial to limit radiation therapy to only some histotypes. The incidence of spinal column deformity after multilevel laminectomy is greater in young patients. It is advisable to implement prevention of spinal deformities by postoperative external immobilization and constant follow-up so as to detect early changes of spinal stability.

Adolescent↗

The freezing and thawing of water in poultry meat and vegetables irradiated by electrons at doses of 0.1-4 kGy.

Poultry meat and some vegetables, irradiated by 5 MeV electrons (0.1-4 kGy), were analysed by differential scanning calorimetry, from 24 h after irradiation. The temperature and enthalpy transitions of the water contained in the irradiated samples were measured and compared with those of unirradiated samples. We analysed 18 meat and 10 vegetable samples for each irradiation dose together with a similar number of unirradiated controls. The mean supercooling temperatures of water in the irradiated poultry meat samples and in some vegetables are significantly lower than those of controls. Moreover, the freezing enthalpies of the irradiated poultry breast are significantly lower than those of controls, while they are unchanged in the other cases. The mean ice melting temperatures and enthalpies are similar for all samples. The amount of the lowering of the water-ice transition depends on the nature of the sample and is highest in poultry breast and lowest in vegetables.

Electrons↗

Repair of two unruptured intracranial aneurysms in the presence of coarctation of the aorta-anesthetic implications and management.

A case of two incidental familial intracranial aneurysms associated with asymptomatic coarctation of the aorta is reported. Priority was assigned to aneurysm surgery, which was accomplished by means of two distinct procedures, both requiring moderate, deliberate hypotension. Invasive monitoring always included radial and femoral as well as pulmonary artery pressures, together with mixed venous oximetry and thermodilution cardiac outputs. Spinal somatosensory-evoked potentials were also continuously registered, to prevent spinal cord ischemia. In fact, even moderate hypotension may critically reduce perfusion in the lower, already hypotensive district, because of coarctation.

Adult↗

Pharmacokinetics of fluconazole in normal volunteers.

The pharmacokinetic profile of fluconazole, after 100 mg i.v. infusion or oral administration of a single 50 mg or 150 mg dose, was investigated in 18 healthy volunteers. At a dose of 100 mg i.v., the half-life (t1/2 beta) was 29.73 +/- 8.05h. The mean residence time in the plasma was 27.56 +/- 5.98 h. The post-distributive volume V beta = 52.16 +/- 9.83 l, approximating that of total body water. Renal excretion accounted for 61.64 +/- 8.80% of the drug elimination after 48 h, with renal clearance Clr = 12.91 +/- 2.83 ml/min. Plasma clearance (Clp) was 21.03 +/- 5.07 ml/min. At oral doses of 50 and 150 mg the distribution and elimination of fluconazole resembled that following i.v. infusion. The peak levels in plasma at 2.5 h were 0.93 +/- 0.13 and 2.69 +/- 0.43 micrograms/ml, respectively. The large distribution volume, the long half-life and mean residence times, combined with a rapid absorption after oral administration, suggest that fluconazole will be effective at a wide range of body sites.

Administration, Oral↗