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L Palombini

Publications and source records attributed to L Palombini.

At least 19 recordsLinked to original sources
PubMed2006

Accumulation of p27(kip1) is associated with cyclin D3 overexpression in the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma.

BACKGROUND: The down regulation of protein p27(kip1) (p27) in most cases of thyroid cancer has relevant diagnostic and prognostic implications. However, the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma expresses more p27 than benign oxyphilic lesions do. AIM: To evaluate the mechanism underlying this difference in expression of p27. METHODS: Because high levels of cyclin D3 lead to p27 accumulation in cell lines and clinical samples of thyroid cancer, the immunocytochemical pattern of cyclin D3 in oxyphilic (n = 47) and non-oxyphilic (n = 70) thyroid neoplasms was investigated. RESULTS: In the whole study sample, there was a significant correlation between p27 and cyclin D3 expression (Spearman's r: 0.64; p<0.001). The expression of cyclin D3 and p27 was significantly higher in the oxyphilic variant of follicular carcinomas than in non-oxyphilic carcinomas (p<0.001). In the former, cyclin D3 overexpression and p27 accumulation were observed in a median of 75% and 55% of cells, respectively. In co-immunoprecipitation experiments, the level of p27-bound cyclin D3 was much higher in oxyphilic neoplasias than in normal thyroids and other thyroid tumours. CONCLUSION: These results show that increased p27 expression in the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma results from cyclin D3 overexpression.

Adenocarcinoma, Follicular↗
PubMed2006

Stroke and treatment with nasal CPAP.

Stroke patients present a high prevalence of obstructive sleep apnea (OSA) and those with OSA have a higher mortality after 1 year and poorer functional outcome compared with others. The aim of this study was to prospectively evaluate the acceptance of nasal continuous positive airway pressure (CPAP) by recent stroke patients with OSA. Recruitment of non-comatose stroke patients with sufficient consciousness for diagnostic evaluation of OSA was performed and they were treated at home with nasal CPAP after hospital calibration and training on the usage of CPAP. Initial evaluation and regular follow-up of the home trial of auto-CPAP was carried out for a duration of 8 weeks. Of 50 initially recruited patients, 32 (100%) responded to the minimum cognitive criteria but seven patients (22%) only used nasal CPAP for 8 weeks. Subject dropout was related to difficulties with CPAP usage as perceived by patient and family members, facial weakness, motor impairment and increase difficulties and discomfort with usage of full-face mask. The majority of OSA stroke patients rejected CPAP treatment. Better education and support of patients and families, and special training sessions in rehabilitation services, will be needed to improve compliance.

Aged↗
PubMed2005

UbcH10 overexpression may represent a marker of anaplastic thyroid carcinomas.

The hybridisation of an Affymetrix HG_U95Av2 oligonucleotide array with RNAs extracted from six human thyroid carcinoma cell lines and a normal human thyroid primary cell culture led us to the identification of the UbcH10 gene that was upregulated by 150-fold in all of the carcinoma cell lines in comparison to the primary culture cells of human normal thyroid origin. Immunohistochemical studies performed on paraffin-embedded tissue sections showed abundant UbcH10 levels in thyroid anaplastic carcinoma samples, whereas no detectable UbcH10 expression was observed in normal thyroid tissues, in adenomas and goiters. Papillary and follicular carcinomas were only weakly positive. These results were further confirmed by RT-PCR and Western blot analyses. The block of UbcH10 protein synthesis induced by RNA interference significantly reduced the growth rate of thyroid carcinoma cell lines. Taken together, these results would indicate that UbcH10 overexpression is involved in thyroid cell proliferation, and may represent a marker of thyroid anaplastic carcinomas.

Animals↗
PubMed2003

p27 Kip1 protein expression in Hashimoto's thyroiditis.

AIMS: Hashimoto's thyroiditis (HT) is an autoimmune disease in which both proliferation and apoptosis are enhanced. p27(Kip1) protein protects tissues from disease mechanisms that involve excessive cell proliferation and apoptosis. This study investigated whether there is loss of p27(Kip1) expression in HT and whether p27(Kip1) immunoreactivity has any relation to the proliferative indicator Ki-67. Because p27(Kip1) is regulated through either degradation, mediated by the S phase kinase associated protein 2 (Skp2), or sequestration, via D3 cyclin, the expression of these proteins was also investigated. METHODS: Immunohistochemistry was used to assess p27(Kip1), Ki-67, Skp2, and cyclin D3 expression in 19 cases of HT and in 10 normal thyroids. The results were evaluated by image analysis and reported as labelling indices (LIs) in both groups. RESULTS: The p27(Kip1) LI was lower in HT than in normal thyroid (28% v 75%; p < 0.001), whereas Ki-67 (1.13% v 0.13%), Skp2 (0.74% v 0.15%), and cyclin D3 (1.56% v 0.00%) LIs were higher in HT than in normal thyroids (p < 0.001). There was no correlation between p27(Kip1) and the expression of Ki-67, Skp2, and cyclin D3. CONCLUSIONS: p27(Kip1) downregulation is not exclusive to tumours but occurs also in HT, independently of the proliferative status and of changes in Skp2 and cyclin D3 expression. Further investigation is required to understand the mechanisms leading to p27 deregulation because these observations suggest that the regulation of p27(Kip1) expression in epithelial thyroid cells may play a role in HT pathogenesis.

Biomarkers↗
PubMed2001

Follicular variant of papillary carcinoma: cytologic findings on FNAB samples-experience with 16 cases.

Between January 1, 1992 and December 31, 1997, a cytopathological diagnosis of follicular variant of papillary thyroid carcinoma (FVPC) was made on a series of 16 out of 18 patients with palpable nodules who underwent fine-needle aspiration biopsy (FNAB) in our Department. The results of aspiration biopsy were followed by histopathological examination of the surgically excised tissues. There were three false-negative aspirations (16.6%), of which two were probably bound to fine-needle sampling and one due to a mixture of benign and malignant cells which had originally gone unrecognized. The accuracy of the cytopathologic diagnosis in this variant was 88.8%. An analysis of the diagnostic cytopathological criteria was performed, which demonstrated the importance of both architectural features (monolayered and branching sheets, microacinar structures, and their combinations) and nuclear features (presence of nuclear grooves). Background -bound features were mainly represented by dense, nonfilamentous colloid. The cytopathologic findings in FVPC were compared to those found in a series of 10 usual papillary carcinomas (UPC) and 10 follicular neoplasms (FN). These latter had originally been diagnosed by FNAB and were subsequently classified histologically as follicular adenoma (n = 6), follicular carcinoma (n = 3), or adenomatoid colloid nodule (n = 1). Statistical evaluation was performed on the cytopathological findings in the three classes of lesions (FVPC, UPC, and FN) as to their presence and relative frequency or absence by using a nonparametric one-way ANOVA (Kruskall-Wallis) and, where necessary, a Mann-Whitney U test. Papillary cellular fragments and multinucleated giant cells (P < 0.005), nonfilamentous dense colloid, squamoid cells, and syncytia were significantly more represented in UPC than in FVPC (P < 0.05), while histiocytes were significantly more frequent in FVPC (P < 0.005). Other nuclear and/or background features were significant only in the distinction between papillary carcinomas as a group and FN. The cytological differential diagnosis of the FVPC is briefly discussed with relevance to the possible pitfalls caused by its peculiar cyto- and histomorphology.

Adult↗
PubMed2001

Cervical positioning for reduction of sleep-disordered breathing in mild-to-moderate OSAS.

The objective of this study was to assess whether cervical positioning could improve mild to moderate cases of the obstructive sleep apnea syndrome (OSAS). Eighteen subjects recruited from a tertiary sleep disorders clinic population with mild to moderate cases of OSAS were evaluated using a custom-fitted cervical pillow designed to increase upper airway caliber by promoting head extension. The subjects used their usual pillows during two consecutive recorded baseline nights in our laboratory. They then used the cervical pillow for 5 days at home and returned for 2 consecutive recorded nights at our laboratory to use the cervical pillow. During the nights in our laboratory, the subjects completed questionnaires, were videotaped to record head and body position, and had full polysomnography. The subjects had a significant trend toward improvement in their respiratory disturbance indices with use of the cervical pillow, despite spending more time in the supine position and having similar amounts of REM sleep in the baseline and experimental conditions. They also had nonsignificant trends toward improvements in their sleep efficiency and subjective depth of their sleep as well as significantly fewer arousals and awakenings in the experimental compared with the baseline condition. We propose that cervical positioning (i.e., head extension) with a custom-fitted cervical pillow provides a simple, noninvasive, and comfortable means of reducing sleep-disordered breathing in patients with mild to moderate OSAS.

Adolescent↗
PubMed2001

Sleep and wakefulness in somnambulism: a spectral analysis study.

OBJECTIVE: The sleep structure and the dynamics of EEG slow-wave activity (SWA) were investigated in 12 young adults and age- and gender-matched controls. METHODS: Polysomnography was performed in subjects with well-documented chronic sleepwalking and in matched controls. Blinded visual scoring was performed using the international criteria from the Rechtschaffen and Kales atlas [A manual of standardized technology, techniques and scoring systems for sleep stages of human subjects. Los Angeles: UCLA Brain Information Service, Brain Research Institute, 1968.] and by determining the presence of microarousals as defined in the American Sleep Disorders Association (ASDA) atlas [Sleep 15 (1992) 173.]. An evaluation of SWA overnight was performed on total nocturnal sleep to determine if a difference existed between groups of subjects, since sleepwalking usually originates with slow-wave sleep. Investigation of the delta power in successive nonoverlapping 4-second windows in the 32 seconds just prior to EMG activity associated with a confusional arousal was also conducted. One central EEG lead was used for all analyses. RESULTS: Somnambulistic individuals experienced more disturbed sleep than controls during the first NREM-REM sleep cycle. They had a higher number of ASDA arousals and presented lower peak of SWA during the first cycle that led to a lower SWA decline overnight. When the investigation focused on the short segment immediately preceding a confusional arousal, they presented an important increase in the relative power of low delta (0.75-2 Hz) just prior to the confusional arousal. CONCLUSION: Sleepwalkers undergo disturbed nocturnal sleep at the beginning of the night. The increased power of low delta just prior to the confusional arousal experienced may not be related to Stages 3-4 NREM sleep. We hypothesize that it may be translated as a cortical reaction to brain activation.

Adult↗
PubMed2001

Variability of respiratory effort in relation to sleep stages in normal controls and upper airway resistance syndrome patients.

OBJECTIVE: Investigation of the role of sleep states on the respiratory effort of controls and subjects with upper airway resistance syndrome (UARS) using nasal cannula/pressure transducer system and esophageal manometry. PATIENTS AND METHODS: One night's monitoring of sleep and breathing, including the determination of peak end inspiratory esophageal pressure (respiratory effort) with esophageal manometry and flow limitation with nasal cannula. Analysis of the data, breath-by-breath, using visual inspection and a computerized program. Setting - a university sleep laboratory. Patients were nine men with UARS and nine control men matched for age, ethnicity, and body mass index. RESULTS: A modulation of respiratory effort by sleep state and stages is seen in all subjects, the lowest noted during REM sleep and the highest associated with Slow Wave Sleep. When total nocturnal breaths are investigated, a significant difference between peak end inspiratory esophageal pressure [(Pes)-considered as an index of respiratory effort] is noted between normal subjects and UARS. Two specific breathing patterns, seen primarily in UARS patients, are NREM sleep stage dependent. Crescendos (defined as more negative peak end inspiratory Pes with each successive abnormal breath) occur mostly during stages 1-2 NREM sleep, while segments consisting of regular and continuous, breath-after-breath, high respiratory efforts are associated with Slow Wave Sleep. Depending on sleep stage, visually scored arousal response displays differences in Pes negativity. The termination of the abnormal breathing pattern, always well defined with Pes, is not necessarily associated with a pattern of 'flow limitation' at the nasal cannula tracing, even when a visually scored EEG arousal is present. CONCLUSIONS: UARS patients have significantly more breaths, with more negative peak end inspiratory Pes, than do control subjects. The modulation of peak end inspiratory Pes (an index of respiratory effort) by sleep stage and state differs in UARS patients and control subjects. The nasal cannula/pressure transducer system may not detect all abnormal breathing pattern during sleep. As indicated by the visual sleep scoring, repetitive arousals may lead to more or less severe sleep fragmentation.

Journal Article↗
PubMed2001

Quantitative assessment of oxyphilic cell lesions of the thyroid gland on fine needle aspiration samples.

OBJECTIVE: To assess the possible contribution by a multiparametric quantitative approach to the cytologic diagnosis of oxyphilic cell (OC) thyroid lesions. STUDY DESIGN: Ten cases of chronic lymphocytic (Hashimoto) thyroiditis and 10 nodular goiters containing oxyphilic cells plus 20 cases of tumors subsequently classified as oxyphilic cell adenomas (10 cases) or oxyphilic cell well-differentiated carcinomas (10 cases) were evaluated. The study was performed on May-Grünwald-Giemsa-stained smears for planimetric measurements. The same smears were destained and Feulgen restained for densitometric measurements. The latter were performed using static cytometry equipment measuring 100 and 20-30 lymphocytes per case for the determination of integrated optical density (IOD). The following parameters were considered: nuclear area, perimeter, maximum diameter, form ELL, form PE, IOD, 5c exceeding rate (5cER) and visual classification of histograms as euploid, polyploid and aneuploid. RESULTS: Mean nuclear area of carcinomas was smaller than that of adenomas, goiter and thyroiditis. Nuclear area was larger in adenomas than in other benign lesions and carcinomas. All the other planimetric parameters were similar in the lesions examined. Four carcinomas and three adenomas were aneuploid, and all the rest were euploid. All the cases of thyroiditis and goiter were euploid or polyploid; four thyroiditis cases showed polyploid histograms and 5cER values > 1. CONCLUSION: Morphometric and densitometric procedures have a limited role in the discrimination of OC lesions, but small nuclear area values may be useful in distinguishing OC carcinoma from other lesions. The role of densitometry seems even more limited because aneuploid histograms may be found among adenomas and carcinomas. Further studies are needed to explain polyploidy and 5cER > 1 in Hashimoto thyroiditis.

Biopsy, Needle↗
PubMed2000

Radiofrequency (pacing and thermic effects) in the treatment of sleep-disordered breathing.

Radiofrequency, whether it is used for pacing or for its thermal liberation properties, has been investigated as a treatment for sleep-disordered breathing. Diaphragmatic pacing has a long history. The problems associated with pacing, which are related to patient selection, equipment failure, disturbances at the electrode/nerve interface, neuromuscular function failure, muscle fatigue, and the physiological consequences of stimulation, will have to be resolved with XIIth nerve stimulation. Radiofrequency thermal ablation has been applied on the tongue of an animal model. In man, turbinates, soft palate tissue and the base of tongue have been treated. These feasibility studies have demonstrated that obstructive sleep apnea syndrome and upper airway resistance syndrome can be completely controlled using radiofrequency thermal ablation in some subjects. These results can be obtained without complications related to speech, taste or swallowing. The treatment can be administered as an outpatient procedure, but many applications are needed, and treatment may span 6 months. Too high a level of radiofrequency will cause pain or otherwise avoidable complications. The determination of which patients will benefit most from these procedures will require further multi-center, placebo-controlled studies.

Ambulatory Care↗
PubMed2000

Upper airway resistance syndrome and its treatment.

Although upper airway resistance syndrome (UARS) is being recognized by a growing number of specialists, its prevalence remains unknown. UARS is associated with nocturnal and daytime complaints and oro-naso-maxillo-mandibular signs. Spectrum analysis of the nocturnal sleep EEG from the central leads indicates significant differences in absolute power in the 12-14 Hz and the 7-9 Hz bands of UARS patients compared to controls. The 0.5-2.0 Hz band also appears to be involved when analyses performed on matched controls are compared to results obtained in subjects treated with nasal CPAP. Several treatment avenues--nasal CPAP, dental devices, surgical procedures, and radiofrequency thermal ablation--have been used for the treatment of UARS. The number of subjects treated have been too low and the protocols too limited to arrive at appropriate outcome recommendations, but many of the approaches have shown positive results, suggesting the possibility of several treatment avenues.

Electroencephalography↗
PubMed2000

A clinical investigation of obstructive sleep apnea syndrome (OSAS) and upper airway resistance syndrome (UARS) patients.

Objective: (i) Evaluation of the clinical differences and similarities presented by patients diagnosed as OSAS and UARS subjects. (ii) Evaluation of the ability of a sleep disorders specialist to dissociate the two syndromes based upon clinical evaluation.Population: 314 subjects were included. They were referred to a sleep disorders clinic with complaints of loud snoring during a 3 month period.Method: The evaluation consisted of: (i) Clinical interview and evaluation. (ii) Administration of validated questionnaires (Sleep Disorders Questionnaire and Epworth Sleepiness Scale). (iii) Establishment of clinical diagnostic and results of polygraphic recording.Results: After clinical evaluation and polygraphic recordings (performed within 3 weeks of initial evaluation) patients were subdivided into two groups: 176 OSAS and 128 UARS. The misclassification of patients by specialists correlated with body mass index (BMI) measurement, with an over classification of patient as OSAS when a high BMI was noted and vice-versa for UARS. The only significant difference between OSAS and UARS patients was an older age and a wider neck circumference in the OSAS group than in UARS patients.Conclusion: Clinical presentation including daytime sleepiness complaint and ESS score is similar for patients with and without drop of oxygen saturation below 90% during sleep. There was always a male predominance within both syndromes, but more women were diagnosed with UARS than with OSAS.

Journal Article↗
PubMed2000

Cyclin-dependent kinase inhibitor p27(Kip1) expression in thyroid cells obtained by fine-needle aspiration biopsy: a preliminary report.

Recent studies on paraffin-embedded tissue have shown that the cyclin-dependent kinase inhibitor p27(Kip1) is expressed in normal thyroid cells, whereas it is downregulated in neoplastic cells. This prospective study was undertaken to assess whether p27(Kip1) staining may also be applied to fine-needle aspiration biopsy (FNAB) samples of the thyroid. We present here our preliminary results on 100 FNABs examined for p27(Kip1) expression. p27(Kip1) expression was assessed by immunocytochemistry; the technique was optimized on smears prepared from a normal thyreocyte cell line (TL5), which conspicuously expresses p27(Kip1), and then applied to FNAB samples prospectively collected from 80 cases of nodular goiter and 20 cases of thyroid neoplasms (10 papillary carcinomas and 10 follicular neoplasms). The TL5 cell culture smears showed that methanol fixation, followed by heat-induced antigen retrieval, is the most suitable technique for p27(Kip1) staining on cytological samples. The FNAB smears similarly treated showed high p27(Kip1) expression (75%) in goiter and a significantly lower expression (35%) in neoplasms (P < 0.0001). Our preliminary results show that: 1) p27(Kip1) protein expression can be reliably assessed on cytological samples; and 2) p27(Kip1) stains nonneoplastic and neoplastic samples in a different fashion, and thus is a useful tool in thyroid cytology.

Adenocarcinoma, Follicular↗
PubMed2000

A new rat model of small vessel stenting.

OBJECTIVES: Restenosis is the major complication of coronary angioplasty and stenting. In addition, the small vessel diameter represents a major limitation to the wide use of the technology. The aim of this study was to assess the feasibility and the vascular response of stent deployment in rat small vessels. METHODS: In 40 Wistar rats (500-550 g) a Nir stent crimped on a 1.5 mm Comet angioplasty balloon catheter was deployed at high pressure in the common carotid artery. Neointimal area, neointima/media ratio and the arterial dimension were assessed immediately and at 7, 14, 21, and 28 days after stenting. RESULTS: After stent deployment, the neointimal area and the neointima/media ratio increased progressively and peaked at 14 days (p < 0.05 vs 0 and 7 days). Alpha-actin-positive cells were found circumferentially organized on the lumen surface. At 21 and 28 days after stenting, the neointima and the neointima/media ratio were not statistically different compared with the results obtained fourteen days after stent deployment. No significant differences in the area of external elastic lamina were observed during the study period. In contrast, the internal lumen area was reduced significantly at 14, 21, and 28 days after the stent deployment. Subacute thrombosis rate after stent implantation was 26.5 %. CONCLUSIONS: The results of this study demonstrated that the balloon expandable stents can be safely placed into rat arteries and the reduction of the internal arterial lumen observed after stent deployment was only due to the neointima formation whereas remodeling did not occur.

Animals↗
PubMed1999

Validation of the sleep-EVAL system against clinical assessments of sleep disorders and polysomnographic data.

OBJECTIVES: To validate the Sleep-EVAL expert system, a computerized tool designed for the assessment of sleep disorders, against polysomnographic data and clinical assessments by sleep specialists. DESIGN: Patients were interviewed twice, once by a physician using Sleep-EVAL and again by a sleep specialist. Polysomnographic data were also recorded to ascertain diagnoses. Agreement between diagnoses generated by Sleep-EVAL and those formulated by sleep specialists was determined via the kappa statistic. SETTINGS: Sleep disorder centers at Stanford University (USA) and Regensburg University (Germany). PATIENTS: 105 patients aged 18 years or over. INTERVENTIONS: NA. RESULTS: Sleep-EVAL made an average of 1.32 diagnoses per patient, compared with 0.93 for the sleep specialists. Overall agreement on any sleep-breathing disorder was 96.9% (Kappa .94). More than half of the patients were diagnosed with obstructive sleep apnea syndrome (OSAS); the agreement rate for this specific diagnosis was 96.7% (Kappa .93). CONCLUSIONS: The findings indicate that the Sleep-EVAL system is a valid instrument for the recognition of major sleep disorders, particularly insomnia and OSAS.

Adult↗
PubMed1999

Epithelioid sarcoma: report of two cases diagnosed by fine-needle aspiration biopsy with immunocytochemical correlation.

Epithelioid sarcoma (ES) is an aggressive soft-tissue malignant tumor generally arising in the distal extremities of young adults. The microscopic diagnosis of ES is often difficult because of its rarity and its possible confusion with other malignant tumors or even with benign granulomatous processes. Two cases of ES and a recurrence of one of these tumors, diagnosed by fine-needle aspiration biopsy (FNAB), are reported. Cytologic smears were quite similar in both cases including the relapse, showing single or loosely arranged groups of medium to large atypical cells. Single cells had well-defined eosinophilic cytoplasms and one or more atypical, eccentrically located nuclei, resulting in a plasmacytoid appearance. Nuclei had fine granular chromatin and one or two large nucleoli. The cells sometimes palisaded along the edges of necrotic material. The immunocytochemical stains showed diffuse cytoplasmic positivity for cytokeratins (CAM 5.2) and both cytoplasmic and cell membrane positivity for vimentin, while S-100 protein and HMB 45 immunostaining were negative, thus supporting the cytological diagnosis of ES, which was subsequently proven on the surgical samples. Diagn. Cytopathol. 1999;21:405-408.

Adult↗