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Biomedical subjects

M Castellano

Publications and source records attributed to M Castellano.

At least 19 recordsLinked to original sources
PubMed2007

Aggressiveness and outcome of papillary thyroid carcinoma (PTC) versus microcarcinoma (PMC): a mono-institutional experience.

BACKGROUND: Papillary thyroid carcinoma (PTC) represents 70%-75% of well-differentiated thyroid cancers. Although most reports have shown that papillary thyroid microcarcinomas (PMC) follow an indolent course, a few series have demonstrated that a significant number of them are associated with extrathyroidal extension and nodal or distant metastases. METHODS: Four hundred eighty-four patients with papillary thyroid cancer (102, PMC; 382, PTC) were enrolled in this study. The median follow-up was 102 months. RESULTS: No difference between PTC and PMC patients was observed for age, gender, multifocality, extrathyroidal extension, and lymph nodes metastasis. The prevalence of nodal involvement developing during the follow-up period was significantly higher in PMC than PTC (58.8% vs. 38.5%, P = 0.002). An unfavorable clinical course occurred in 96 subjects (21.8%). Logistic analysis showed that the strongest association with the worst prognosis was found for age and TNM stage III (P < 0.001). Analysis also confirmed that the presence of intranodular vascularity is a predictor of unfavorable outcome (P = 0.044). CONCLUSIONS: We suggest always performing a total thyroidectomy followed by radiometabolic therapy in papillary carcinomas independent of their size. If the choice in PMCs should be more conservative (hemithyroidectomy), we purpose to limit this procedure to the cancers without Doppler features suggesting intranodular vascular pattern.

Adult↗
PubMed2006

The predictive value of ultrasound findings in the management of thyroid nodules.

BACKGROUND: Thyroid nodules are a common medical problem, but whether fine-needle aspiration cytology (FNAC) is mandated for smaller non-palpable nodules, is controversial. AIM: To evaluate whether ultrasonographic features of thyroid nodules are associated with histological malignancy, and to identify useful criteria for clinical decision-making. DESIGN: Prospective observational study. METHODS: From January 1991 to September 2004, 5198 patients were referred to our hospital for ultrasound evaluation of thyroid nodules. Overall, 7455 nodules (diameters from 6 to 100 mm) were examined; 2865 (38.4%) were <10 mm in diameter. All patients with suspicious or malignant cytology underwent surgery. RESULTS: Of the 349 nodules undergoing surgery, 284 were malignant. The prevalence of cancer was slightly higher in nodules>or=10 mm in diameter vs. those<10 mm (5.5% vs. 3.0%, p<0.01). However, histological type and local aggressiveness were largely independent of nodule size. Microcalcifications (72.2% vs. 28.7%; p<0.001; OR 6.4, 95%CI 4.9-8.4), blurred margins (52.8% vs. 18.8%; p<0.001; OR 4.8, 95%CI 3.8-6.1), solid hypoechoic appearance (80.6% vs. 52.4%; p<0.001; OR 3.8, 95%CI 2.8-5.1), size>or=10 mm (77.4% vs. 64.9%; p<0.001; OR 1.9, 95%CI 1.4-2.5) and intranodular vascular pattern type 2 (61.6% vs. 49.7%; p<0.001; OR 1.6, 95%CI 1.2-2.0) were all significantly more frequent in malignant than in benign nodules. These associations were similar when large and small nodules were analysed separately. DISCUSSION: No single parameter, including nodule size, satisfactorily identifies a subset of patients to be electively investigated by FNAC, although several may be useful in this regard.

Biopsy, Fine-Needle↗
PubMed2006

Ectopic lingual thyroid tissue and acquired hypothyroidism: case report.

Ectopic thyroid tissue with thyroid gland in its normal location is an extremely rare phenomenon. We present a case of a 38-year-old woman who was referred to our hospital with symptoms of hypothyroidism. Thyroid hormone measurement revealed clinical hypothyroidism with elevated anti-thyroid antibodies, neck ultrasonography showed a small tissue with the characteristic of Hashimoto thyroiditis, while the scintigraphy demonstrated only a lingual thyroid. Treatment consisted in L-thyroxine replacement to the euthyroid state. We reviewed the literature with respect to the embryological background and the clinical management of such cases.

Choristoma↗
PubMed2006

A completely automated CAD system for mass detection in a large mammographic database.

Mass localization plays a crucial role in computer-aided detection (CAD) systems for the classification of suspicious regions in mammograms. In this article we present a completely automated classification system for the detection of masses in digitized mammographic images. The tool system we discuss consists in three processing levels: (a) Image segmentation for the localization of regions of interest (ROIs). This step relies on an iterative dynamical threshold algorithm able to select iso-intensity closed contours around gray level maxima of the mammogram. (b) ROI characterization by means of textural features computed from the gray tone spatial dependence matrix (GTSDM), containing second-order spatial statistics information on the pixel gray level intensity. As the images under study were recorded in different centers and with different machine settings, eight GTSDM features were selected so as to be invariant under monotonic transformation. In this way, the images do not need to be normalized, as the adopted features depend on the texture only, rather than on the gray tone levels, too. (c) ROI classification by means of a neural network, with supervision provided by the radiologist's diagnosis. The CAD system was evaluated on a large database of 3369 mammographic images [2307 negative, 1062 pathological (or positive), containing at least one confirmed mass, as diagnosed by an expert radiologist]. To assess the performance of the system, receiver operating characteristic (ROC) and free-response ROC analysis were employed. The area under the ROC curve was found to be Az = 0.783 +/- 0.008 for the ROI-based classification. When evaluating the accuracy of the CAD against the radiologist-drawn boundaries, 4.23 false positives per image are found at 80% of mass sensitivity.

Algorithms↗
PubMed2006

Genetic mutation screening in an italian cohort of nonsyndromic pheochromocytoma/paraganglioma patients.

To assess the prevalence of genetic mutations in nonsyndromic pheochromocytoma/paraganglioma (PHEO/PGL) patients we have performed a systematic search for mutations in the succinate dehydrogenase (SDH) B, C, and D subunits, von Hippel-Lindau (VHL), and RET genes by direct bidirectional sequencing. Patients were selected from the medical records of hypertension centers. After exclusion of syndromic patients, 45 patients with familial (F+, n=3) and sporadic (F-, n=42) cases of isolated PHEO/PGL were considered. They included 35 patients with PHEO, 7 with PGL, and 3 with head/neck PGL (hnPGL). Three patients with PHEO (2F-, 1F+) presented VHL mutations (P86A, G93C, and R167W), six with PGL (4F-, 2F+) were positive for SDH or VHL mutations (SDHB R230G in two patients, SDHB S8F, R46Q, R90Q, and VHL P81L in one subject each), and one with hnPGL carried the SDHD 348-351delGACT mutation. We have also detected missense (SDHB S163P, SDHD H50R and G12S), synonymous (SDHB A6A, SDHD S68S), and intronic mutations that have been considered nonpathological polymorphic variants. No mutation was found in SDHC or RET genes. Our data indicate that germline mutations of VHL and SDH subunits are not infrequent in familial as well as in sporadic cases of nonsyndromic PHEO/PGL (overall, 12 of 45 probands, 22%). Accordingly, screening for such mutations seems to be justified. However, a more precise characterization of the functional relevance of any observed sequence variant and of other genetic and environmental determinants of neoplastic transformation is essential in order to plan appropriate protocols for family screening and follow-up.

Adrenal Gland Neoplasms↗
PubMed2005

Cost-effectiveness of fine-needle-aspiration cytology of thyroid nodules with intranodular vascular pattern using two different needle types.

OBJECTIVE: To compare the cytological findings of hypoechoic thyroid nodules with intranodular vascular pattern (pattern II) obtained by two different needles (Neolus 25 gauge, Chemil, Wenzhou, China vs Yale Spinal 25 gauge, Becton Dickinson, Madrid, Spain) in euthyroid patients and to evaluate their cost-effectiveness. METHODS: From January 2001 to December 2003, 480 euthyroid patients with a hypoechoic thyroid nodule pattern II were referred for US-FNAC. The nodules were alternatively evaluated by Neolus or by Yale Spinal with the stylet (YS+) or without the stylet (YS-), in order to evaluate if the cytological results could be due to the presence of the stylet or to the different length of the two needles. For each nodule two passes were performed and the material was obtained by capillary action. Material was smeared on slides, fixed, and stained by Papanicolaou techniques. Cytological specimens were evaluated in blind by the same experienced cytopathologist. RESULTS: Inadequate cytological specimens because of blood contamination were present in 30 (18.7%) samples by Neolus needle and in 22 (13.8%) by YS- compared to only 5 (3.1%) by YS+. In 6 (20%) cases of the 30 repeated US-FNAC by Neolus and in 4 (18%) of the 22 US-FNAC by YS-, material remained inadequate for diagnosis because of blood contamination. All the five repeated samples obtained by YS+ became adequate for diagnosis and resulted benign nodules. Direct costs of US-FNAC procedure are currently 72.30 Euro including cytological examination. The cost of Neolus and Yale needles is 0.19 Euro and 3.0 Euro, respectively. The estimated total cost to obtain a cytological diagnosis by a Neolus needle (160 + 30 repeated US-FNAC) was 13809.2 Euro vs 12919.5 Euro by Yale Spinal needle (160 + 5 repeated US-FNAC). CONCLUSION: This study demonstrates that the use of Yale Spinal needles greatly reduces inadequate cytological specimens, and therefore limits both direct and indirect costs.

Biopsy, Fine-Needle↗
PubMed2004

Treatment of severe chronic venous insufficiency using the subfascial endoscopic perforator vein procedure.

BACKGROUND: Before 1985, corrective surgical procedures for patients with chronic venous insufficiency and venous ulcers were performed using long incisions through diseased skin and subcutaneous tissues. The procedure, involving ligation of incompetent perforator veins, known as "the Linton operation," often was complicated by wound infections and poor healing. This changed in 1985 when G. Hauer demonstrated a new surgical technique for direct visual identification of the incompetent perforator veins using an endoscope in the subfascial space. This seminal contribution marked the advent of subfascial endoscopic perforator vein surgery (SEPS). METHODS: From 1996 to 2004, the authors group prospectively collected data on 110 patients with chronic venous insufficiency who underwent a SEPS procedure. Preoperative assessment of the limb's vascular status consisted of color-flow duplex ultrasound imaging and ascending and descending phlebography to locate vein valve incompetence, along with venous mapping. The ages of the patients ranged from 42 to 82 years (mean, 60 years). A total of 128 limbs underwent the SEPS procedure in the cohort of 110 patients. According to CEAP classification for venous limb disease, 60 limbs belonged to group C5 (skin changes, pigmentation, venous eczema, lipodermatosclerosis, healed ulcer) and 68limbs to group C6 (skin changes and active ulceration). RESULTS: The 110 patients underwent 128 SEPS procedures without significant morbidity. Of the 68 limbs in class C6, 54 showed ulcer healing within the follow-up period of 12 weeks. The remaining 14 limbs in class C6 achieved ulcer healing within 24 weeks. In this latter group, 10 patients had venous ulcers larger than 4 cm in diameter. These patients underwent a split-thickness skin graft at the time the SEPS procedure was performed. The grafts remained healed during a 2-year follow-up period. CONCLUSIONS: This study demonstrated the effectiveness of the SEPS procedure when incorporated into the overall treatment strategy for patients with chronic venous insufficiency. Minimal postoperative complications accompanied by ulcer healing and relief of lower extremity symptoms were achieved for all the patients, underscoring the important role of incompetent perforator veins in the formation of chronic venous insufficiency.

Adult↗
PubMed2004

Modification of cellulose fibres with organosilanes: Under what conditions does coupling occur?

Different cellulose substrates and organosolv lignin were treated heterogeneously with organic solutions of trialkoxysilanes bearing variable function on the forth substituent. It was shown unambiguously for the first time that Si-OR does not react with the hydroxy groups of cellulose even at high temperature, whereas it condenses with the phenolic OH of lignin. The addition of moisture to these systems induces the partial hydrolysis of the siloxane moieties and the ensuing silanol groups can then react with the cellulose OH, but only at high temperature. Using the latter systems and a siloxane bearing a polymerizable function, it was possible to attach poly(methylmethacrylate) chains to the surface of cellulose fibres through a two-step procedure.

Journal Article↗
PubMed2004

The role of personality disorders on drug dependence treatment outcomes following inpatient detoxification.

AIMS: The present 6 month follow-up study was conducted to investigate the possible influence of comorbid personality disorders on drug treatment, as well as associated psychopathology and HIV-related risk behaviors outcomes. SUBJECTS AND METHODS: Data were collected initially from a consecutive sample of 74 patients with a diagnosis of opiate abuse or dependence, admitted for inpatient detoxification. RESULT: During intake, 80.9% of patients reported at least one HIV-related risk behavior in the previous 6 months. Not using condoms during sexual intercourse was the most common and the only risk behavior that showed a statistically significant reduction over the follow-up period. A total of 58.1% of subjects had at least one personality disorder (PD). Borderline PD was the most prevalent. However, antisocial PD was the only PD that influenced substance use outcomes. The presence of this diagnosis increased the chance of worse opiate use outcomes, but decreased likelihood of not using condoms. Patients with low obsessive-compulsive PD dimensional scores showed a significant increase in the number of risk behaviors. However, these influences were only seen at the 3-month follow-up assessment. CONCLUSIONS: These results suggest that personality disorders need to be considered when planning effective interventions for opiate dependent individuals and when preparing and evaluating HIV risk-reduction interventions, particularly for the more severe substance dependent patients.

Adult↗
PubMed2003

Search for the prewave zone effect in transition radiation.

Results of the first experimental search for the effect of the prewave zone in near-infrared transition radiation are presented. A substantial difference in the spatial distribution of transition relation for two different wavelengths (450 nm and 1600 nm) was observed. Experimental data are in a good, though not complete, agreement with the theory.

Journal Article↗
PubMed2003

Circulating adhesion molecules and carotid artery structural changes in patients with noninsulin-dependent diabetes mellitus.

Hypertension and non insulin-dependent diabetes mellitus (NIDDM) are well-known risk factors for atherosclerotic disease. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) may exert a relevant role in the pathogenesis of atherosclerosis; their prognostic relevance has been recently demonstrated. The aim of the study was to investigate possible inter-relation between circulating adhesion molecule levels, carotid artery structure and endothelial function in 15 patients with NIDDM, as well as in 15 patients with both NIDDM and essential hypertension (NIDDM+EH) compared with 15 normal subjects (NS) and 15 euglycaemic patients with EH, matched for age, sex and body weight. All subjects were submitted to a biopsy of the gluteal subcutaneous fat. Small arteries were dissected and mounted on a micromyograph, and the media-to-lumen (M/L) ratio was then calculated. Carotid artery structure was investigated by Doppler ultrasound. Endothelial function was evaluated by investigation of the flow-mediated dilatation (FMD) of the brachial artery. ICAM-1 and VCAM-1 plasma levels were measured by ELISA. ICAM-1 and VCAM-1 plasma levels were significantly greater and FMD smaller in EH, NIDDM and NIDDM+EH than in NS, but no difference was observed among the three pathological groups. Carotid artery structural changes were more pronounced in NIDDM+EH. No significant difference was observed among NIDDM, EH and NS. The M/L ratio of subcutaneous small resistance arteries was significantly greater in NIDDM+EH than in NIDDM or EH. NS had a smaller M/L ratio than the other groups. Significant correlations were observed between ICAM-1 plasma levels and indices of carotid artery structure in diabetic patients. However, the relations were close only in NIDDM+EH. In conclusion, our data suggest that NIDDM+EH may present more pronounced vascular structural alterations than NIDDM, and that adhesion molecules plasma levels are closely inter-related with carotid artery structural alterations, at least in NIDDM+EH, but not with M/L ratio of small resistance arteries.

Carotid Arteries↗
PubMed2002

Generation of GW radiation pulses from a VUV free-electron laser operating in the femtosecond regime.

Experimental results are presented from vacuum-ultraviolet free-electron laser (FEL) operating in the self-amplified spontaneous emission (SASE) mode. The generation of ultrashort radiation pulses became possible due to specific tailoring of the bunch charge distribution. A complete characterization of the linear and nonlinear modes of the SASE FEL operation was performed. At saturation the FEL produces ultrashort pulses (30-100 fs FWHM) with a peak radiation power in the GW level and with full transverse coherence. The wavelength was tuned in the range of 95-105 nm.

Journal Article↗
PubMed2002

Loss of p16 expression is associated with histological features of melanoma invasion.

While mutations of CDKN2A are associated with melanoma predisposition, the precise role of its gene product p16 in the development of sporadic melanoma is less clearly understood. We sought to determine the prevalence of p16 expression using immunohistochemical analysis in a population-based sample of melanoma tumours, and also to identify histological, phenotypic and environmental factors associated with the presence or absence of p16 expression. We conducted face-to-face interviews with 108 patients newly diagnosed with melanoma to ascertain their history of sun exposure, and recorded various phenotypic parameters. Paraffin sections of tumours from these patients were stained with an anti-p16 monoclonal antibody following antigen retrieval. Overall, 52 (48%) tumours expressed p16; nodular melanomas had significantly lower levels of p16 immunoreactivity than superficial spreading melanomas (P = 0.015). While no association was found between p16 expression and host phenotype, loss of p16 staining was associated with thicker lesions (p = 0.084) and a high mitotic index (P = 0.013). Taken together, these findings are consistent with loss of p16 being a late event in the progression of sporadic primary melanomas, being associated with tumours of a more aggressive nature.

Aged↗
PubMed2001

Measurements of coherent diffraction radiation and its application for bunch length diagnostics in particle accelerators.

Measurements of coherent diffraction radiation from a slit of variable width generated by short electron bunches were performed in millimeter and submillimeter ranges. Experimental data are compared with the transition radiation case and theoretical predictions. A more realistic description than the conventional theory is necessary to account for the data correctly. No noticeable difference in the estimated bunch length was observed using diffraction radiation in a wide range of slit widths and transition radiation.

Journal Article↗
PubMed2001

The effects of dihydropyridine and phenylalkylamine calcium antagonist classes on autonomic function in hypertension: the VAMPHYRE study.

The aim of the present study was to compare the effects of a long-acting dihydropyridine (amlodipine) and a nondihydropyridine (verapamil) on autonomic function in patients with mild to moderate hypertension. A total of 145 patients with a diastolic blood pressure (BP) between 95 and 110 mm Hg received 8 weeks of verapamil sustained release (240 mg) and amlodipine (5 mg) in a prospective randomized, double blind, cross-over study, both after 4 weeks of placebo. The 24-h autonomic balance was measured by analysis of 24-h heart rate variability and short-term autonomic control of BP by baroreflex sensitivity measurements. Plasma norepinephrine was sampled at rest. Blood pressure was equally reduced from 153/100 mm Hg to 139/91 mm Hg with verapamil and 138/91 mm Hg with amlodipine, P = .50/.59. The low- to high-frequency ratio (LF/HF), reflecting sympathovagal balance, was higher with amlodipine than with verapamil (4.66 v 4.10; P = .001). Baroreflex function was improved by both treatments; however, baroreflex sensitivity (BRS) was significantly higher with verapamil than with amlodipine (8.47 v 8.06 msec/mm Hg; P = .01). Plasma norepinephrine (NE) level was higher with amlodipine than with verapamil (1.59 v 1.32 nmol/L; P < .0001). Amlodipine induces a shift in sympathovagal balance, as measured by heart rate variability indices and plasma NE, toward sympathetic predominance compared with vagal predominance with verapamil. Short-term autonomic control of BP, as assessed by BRS, is more effectively improved by verapamil than by amlodipine. These contrasting effects on autonomic function suggest that the nondihydropyridine calcium antagonist verapamil may have additional beneficial effects beyond lowering BP compared with the dihydropyridine amlodipine.

Adult↗
PubMed2001

Contrasting effects of verapamil and amlodipine on cardiovascular stress responses in hypertension.

AIMS: To compare the effects of two long-acting calcium antagonists of different types on cardiovascular stress responses in hypertension. METHODS: One-hundred and forty-five patients with mild to moderate hypertension and a mean (+/- s.e.mean) age of 51 +/- 0.9 years received for 8 weeks the phenylalkylamine verapamil sustained release (240 mg) and the dihydropyridine amlodipine (5 mg) in a double-blind cross-over design, both after 4 weeks of placebo. Blood pressure, heart rate and plasma noradrenaline were monitored during 3 min of sustained isometric handgrip and 2 min of cold pressor. RESULTS: Blood pressure was equally reduced by both drugs. After 3 min handgrip, systolic blood pressure, heart rate and rate-pressure product were lower with verapamil compared with amlodipine. Verapamil attenuated the increases in systolic blood pressure (25 +/- 2 vs 30 +/- 2 mmHg, difference 4.6, 95% CI (1.0, 8.1), P < 0.01) and rate-pressure product (3.1 +/- 0.2 vs 3.6 +/- 0.3 x 10(3) mmHg x beats min(-1), difference 0.5, 95% CI (0.1, 0.9), P < 0.01) during handgrip compared with amlodipine. Similar results were observed during cold pressor. Plasma noradrenaline levels were lower with verapamil compared with amlodipine at rest and after both tests, but the increases in plasma noradrenaline were not significantly different. CONCLUSIONS: Verapamil is more effective in reducing blood pressure and rate-pressure product responses to stress compared with amlodipine. Although plasma noradrenaline is lower with verapamil at rest and after stress, the increase during stress is not different.

Adult↗
PubMed2001

Flow-mediated dilatation of the brachial artery and left ventricular geometry in hypertensive patients.

OBJECTIVES: In arterial hypertension, the spectrum of geometric patterns in the left ventricle may parallel the structural alterations detected in the carotid arteries and in subcutaneous small arteries. It has been also reported that hypertensive left ventricular hypertrophy (LVH) may be associated with endothelial dysfunction, as evaluated by the response of coronary or forearm vasculature to acetylcholine infusion. The aim of this study was to evaluate the flow-mediated vasodilatation (FMD) of the brachial artery, non-invasive estimate of endothelium-dependent vasodilatation according to left ventricular geometric adaptations in hypertensive patients. METHODS AND RESULTS: In 16 normotensive (nine males, seven females, aged 40-68 years) and in 78 hypertensive subjects (50 males, 28 females, aged 42-67 years), we performed an echocardiographic study for the measurement of left ventricular mass index (LVMI) and relative wall thickness (RWT); we measured to a high resolution the brachial artery diameter at rest, during reactive hyperaemia (5 min of brachial artery occlusion) and after sublingual glyceril trinitrate (GTN); brachial artery flow velocity was measured by pulsed Doppler. Twenty-six hypertensive patients had a normal LVMI (LVMI < 51 g/ m2.7) and geometry (RWT < 0.44), five had concentric remodelling (RWT > or = 0.44), and concentric and eccentric LVH were observed in 19 and 28 patients, respectively. FMD was reduced in hypertensive patients as compared with normotensive subjects (P< 0.01). No correlation was found between FMD and LVMI (r= -0.078) or RWT (r = 0.049); in addition, no difference in FMD was found among the left ventricular geometric patterns in hypertensive patients. CONCLUSIONS: In hypertensives, the presence of endothelial dysfunction is not associated with the LVH or with different left ventricular geometric patterns, suggesting that different and independent mechanisms may be responsible for the presence of LVH and of endothelial dysfunction.

Adult↗