PubMed Health⌕ Search

Biomedical subjects

S Motta

Publications and source records attributed to S Motta.

At least 19 recordsLinked to original sources
PubMed2006

Formation of self-organized nanoparticles by lecithin/chitosan ionic interaction.

In this work the production of auto-assembled nanoparticles obtained by the mixing of chitosan and lecithin is presented. The size and surface charge of the nanoparticles were studied as function of the weight ratio between components, the viscosity of the polysaccharide and the pH of the colloidal suspension. In order to elucidate the structure of nanoparticles, micro-FT-IR and elastic neutron scattering experiments have been performed. Results evidenced a strong electrostatic interaction between components and a structure that is neither that of homogeneous spheres nor of coated unilamellar vesicles. Preliminary encapsulation experiments with progesterone, as model lipophilic drug, showed good encapsulation efficiencies.

Algorithms↗
PubMed2005

Modeling and simulation of cancer immunoprevention vaccine.

UNLABELLED: We present an in silico model that simulates the immune system responses to tumor cells in naive and vaccinated mice. We have demonstrated the ability of this model to accurately reproduce the experimental results. MOTIVATION: In vivo experiments on HER-2/neu mice have shown the effectiveness of Triplex vaccine in the protection of mice from mammary carcinoma. Full protection was conferred using chronic (prophylactic) vaccination protocol while therapeutic vaccination was less efficient. Our in silico model was able to closely reproduce the effects of various vaccination protocols. This model is the first step towards the development of in silico experiments searching for optimal vaccination protocols. RESULTS: In silico experiments carried out on two large statistical samples of virtual mice showed very good agreements with in vivo experiments for all experimental vaccination protocols. They also show, as supported by in vivo experiments, that the humoral response is fundamental in controlling the tumor growth and therefore suggest the selection and timing of experiments for measuring the activity of T cells. CONTACT: francesco@dmi.unict.it SUPPLEMENTARY INFORMATION: http://www.dmi.unict.it/CIG/suppdata_bioinf.html.

Animals↗
PubMed2003

[Comparative compositional mapping of chicken and quail chromosomes].

The distribution of various isochore families on mitotic chromosomes of domestic chicken and Japanese quail was studied by the method of fluorescence in situ DNA--DNA hybridization (FISH). DNA of various isochore families was shown to be distributed irregularly and similarly on chromosomes of domestic chicken and Japanese quail. The GC-rich isochore families (H2, H3, and H4) hybridized mainly to microchromosomes and a majority of macrochromosome telomeric regions. In chicken, an intense fluorescence was also in a structural heterochromatin region of the Z chromosome long arm. In some regions of the quail macrochromosome arms, hybridization was also with isochore families H3 and H4. On macrochromosomes of both species, the pattern of hybridization with isochores of the H2 and H3 families resembled R-banding. The light isochores (L1 and L2 families) are mostly detected within macrochromosome internal regions corresponding to G bands, whereas microchromosomes lack light isochores. Although mammalian and avian karyotypes differ significantly in organization, the isochore distribution in genomes of these two lineages of the warm-blooded animals is similar in principle. On macrochromosomes of the two avian species studied, a pattern of isochore distribution resembled that of mammalian chromosomes. The main specific feature of the avian genome, a great number of microchromosomes (about 30% of the genome), determines a compositional specialization of the latter. This suggests the existence of not only structural but also functional compartmentalization of the avian genome.

Animals↗
PubMed2001

Aerodynamic findings in esophageal voice.

OBJECTIVE: To define the perceptive and aerodynamic characteristics of esophageal voice in relation to different rehabilitation modalities. DESIGN: Cross-sectional study comparing perceptive and aerodynamic variables in 3 subject groups. SETTING: Referral center. SUBJECTS: A total of 19 subjects who underwent total laryngectomy were divided into groups A and B. Group A consisted of 13 subjects (who required speech therapy)-8 good speakers (subset A(1) who were >80% intelligible) and 5 mediocre speakers (subset A(2) who were <70% intelligible). Group B consisted of 6 subjects with a tracheoesophageal prosthesis (who were >90% intelligible). MAIN OUTCOME MEASURES: Perceptive variables included phonatory pauses and stomal noise. Aerodynamic variables included maximum phonation time, phonatory flow, phonatory volume, postphonatory volume, intensity, and articulatory pressure. RESULTS: Phonatory pauses and stomal noise statistically differentiated group A from group B and good speakers from mediocre speakers. Phonation time, phonatory volume, and phonatory flow were statistically higher in group B subjects compared with group A subjects. Postphonatory volume was significantly higher in group A. Intraoral pressure and postphonatory volume were statistically higher in subset A(2) subjects compared with subset A(1) subjects while maximum phonation time was significantly higher in subset A(1) subjects compared with subset A(2) subjects. CONCLUSIONS: In subset A(1) subjects a positive ratio between phonatory volume and phonatory flow was maintained with an adequate phonation time. In subset A(2) subjects a reduced phonatory volume was associated with a more rapid dispersion of phonatory flow, lower duration of phonation, and frequent pauses; stomal noise and consonant hyperarticulation worsened the voice performance in this group. In group B subjects the positive ratio between phonatory volume and phonatory flow represented the prerequisite of speech without frequent pauses.

Cross-Sectional Studies↗
PubMed2001

Compositional mapping of chicken chromosomes and identification of the gene-richest regions.

'Compositional chromosomal mapping', namely the assessment of the GC level of chromosomal bands, led to the identification, in the human chromosomes, of the GC-richest H3+ bands and of the GC-poorest L1+ bands, which were so called on the basis of the isochore family predominantly present in the bands. The isochore organization of the avian genome is very similar to those of most mammals, the only difference being the presence of an additional, GC-richest, H4 isochore family. In contrast, the avian karyotypes are very different from those of mammals, being characterized, in most species, by few macrochromosomes and by a large number of microchromosomes. The 'compositional mapping' of chicken mitotic and meiotic chromosomes by in-situ hybridization of isochore families showed that the chicken GC-richest isochores are localized not only on a large number of microchromosomes but also on almost all telomeric bands of macrochromosomes. On the other hand, the GC-poorest isochores are generally localized on the internal regions of macrochromosomes and are almost absent in microchromosomes. Thus, the distinct localization of the GC-richest and the GC-poorest bands observed on human chromosomes appears to be a general feature of chromosomes from warm-blooded vertebrates.

Animals↗
PubMed2001

Occult lymph node metastases in supraglottic cancers of the larynx.

Occult cervical lymph node metastases may often be associated with cancers of the supraglottic larynx. The aims of this investigation were: (1) to determine the incidence of occult lymph node metastases in patients with cancer of the larynx; (2) to assess whether the presence of such metastases was related to the extent of the primary tumor (T) and its grading (G); and (3) to discuss which therapeutic approach should be followed in treating clinically occult lymph node metastases. Our investigation included 97 patients who underwent supraglottic horizontal laryngectomy and elective cervical lymph node dissection. The incidence of occult lymph node metastases in the series considered was 27%. Based on the preoperative staging of the tumor, 14% of the cases had metastatically involved lymph nodes in the T1 tumors, 21% in the T2 tumors, 35% in the T3, and 75% in the T4. In the statistical analysis, a significant difference was shown to exist when T1 + T2 and T3 + T4 (P = 0.04) were compared. In terms of grading, occult metastases were found in 16% of the G1 tumors, 27% of the G2, and 42% of the G3. The statistical analysis demonstrated a significant difference between G1 and G3. In brief, the incidence of occult metastases was higher for the less differentiated tumors and for the ones with a higher T value; the effects of both factors are combined thereby increasing the rate of occult metastases (P = 0.05).

Adult↗
PubMed2001

[Microlaryngoscopy treatment of laryngeal dysplasia with CO2 laser].

Classification of laryngeal dysplasia, the most appropriate treatments and criteria for evaluation of the results is still a highly controversial issue. The objectives of the present study on the treatment of laryngeal dysplasia lesions are to: 1) evaluate the relative incidence of the various forms of dysplasia in relation to grading of the histopathological findings; 2) establish the prognosis for the various forms of dysplasia considered; 3) determine the results achieved by the author's treatment protocol according to the characteristics of the dysplasia; 4) critically evaluate the classifications of laryngeal dysplasia found in the literature in view of the results of the present study. The study involved 141 patients with vocal cord dysplasia (134 men, 7 women; mean age: 56.2 years) who had come under observation at the E.N.T. Dept. of the University of Naples "Federico II" between January 1981 and April 1998. In all cases the dysplasia was removed by CO2 laser microlaryngoscopy. Of the 141 patients 89 (63.2%) showed mild dysplasia, 14 (9.9%) moderate dysplasia, 20 (14.2%) severe dysplasia and 18 (12.7%) in situ carcinoma. The five-year survival rate showed an overall actuarial survival of 89.1% for all patients while the corrected actuarial survival was 98.5% and local disease control was 86.1%. In 17 cases (12%) the dysplasia lesion recurred, in 11 (7.8%) an infiltrating carcinoma arose. Recurrences in the dysplasia were encountered in 9% of the patients with mild lesions, 7.1% of those with moderate dysplasia, 15% of the subjects with the severe form and in 27.7% of those with in situ carcinoma. An infiltrating carcinoma arose in 5.6% of the cases of mild lesion, in 7.1% of the medium dysplasias, 5% of the severe forms and in 22.2% of those with in situ carcinoma. The recurrences and infiltrating carcinomas were successfully treated with endoscopic CO2 laser surgery. Only three cases (2.1%) required radical surgery (total laryngectomy): these were patients who had not quit smoking and who had not adhered to the planned follow-up. One of the latter patients died with widespread metastases of the laryngeal cancer. The significantly higher incidence of dysplasia recurrences (P = 0.028) and infiltrating carcinomas (P = 0.015) in those patients with in situ carcinoma shows that, when preparing classification and determining prognosis, these pathologies should be considered separately. Moreover, they require a particularly precise follow-up. In conclusion, the following observations can be drawn from the study: mild and moderate dysplasias are more frequent as compared to severe dysplasia and carcinoma in situ; carcinoma in situ should be distinguished for classification and prognosis from dysplasias, considering their different clinical course and evolution; CO2 laser surgery in these forms is a valid therapeutic approach for its precision, the achievable results, the reduced discomfort to patients and for its evident cost-effectiveness.

Adult↗
PubMed2000

Phenolphthalein induces chromosome aberrations in human and Chinese hamster liver cells (CHEL) cultured in vitro.

Phenolphthalein is a nonprescription laxative agent that has been widely used during this century. Recent studies in animal models have shown that phenolphthalein has carcinogenic activity. In order to assess cytogenetic effects on human cells in vitro, we tested phenolphthalein in a chromosome aberration assay in human embryo cells derived from amniotic fluid. Our results show that phenolphthalein induces a significant increase in the frequency of chromosome aberrations in human cells. The lowest dose level at which the clastogenic effect is evident is 23.2 microg/ml. Similar positive results were obtained in a Chinese hamster liver cell line, which is metabolically competent to activate different classes of promutagens and procarcinogens into biologically active metabolites. Instead, parallel experiments in Chinese hamster ovary cells did not show any clastogenic effect due to phenolphthalein. These latter data suggested that phenolphthalein acts as a promutagen and must be metabolically activated to exert its clastogenic effect. Teratogenesis Carcinog. Mutagen. 20:209-217, 2000.

Amniotic Fluid↗
PubMed2000

A multicenter trial of specific local nasal immunotherapy.

OBJECTIVE: To assess the efficacy and safety of specific local nasal immunotherapy (LNIT) in powder form in patients with allergic rhinitis, using subjective and objective parameters. STUDY DESIGN: A double-blind randomized multicenter trial of 102 patients with allergic rhinitis who were treated with specific LNIT for 8 consecutive months. METHODS: After identifying allergens with the skin prick test and sensitization threshold dose with the specific nasal provocation test, 102 patients were selected, of whom 55 were allergic to mites and 47 were allergic to Graminaceae or Parietaria pollen. The specific treatments were self-administered using an insufflator in two phases (phase 1: increasing doses; phase: 2, maintenance dose). Patients were evaluated before and after 32 weeks of treatment by subjective analysis of their self-reported symptoms and by objective analysis of nasal provocation test, nasal resistance by anterior rhinomanometry, and mucociliary clearance time. RESULTS: Clinical efficacy of LNIT for allergy to mites and pollens was confirmed by the differences in the symptoms score between the active group and the placebo group. The nasal provocation test results confirmed that this difference was statistically significant. The rhinomanometric analysis gave positive results for the treated group mainly in LNIT for mites. No differences in mucociliary clearance time were found. CONCLUSIONS: Specific LNIT is effective for allergic rhinitis and appears to offer considerable advantages over other hyposensitization methods. It can be done at home, patient compliance is good, and the treatment is safe.

Administration, Intranasal↗
PubMed2000

Genomic localization of the human genes TAF1A, TAF1B and TAF1C, encoding TAF(I)48, TAF(I)63 and TAF(I)110 subunits of class I general transcription initiation factor SL1.

Human SL1 is a general transcription initiation factor (GTF) essential for RNA polymerase I to start rRNA synthesis at class I promoters. It is comprised of the TATA box-binding protein (TBP) and three TBP-associated factors (TAF(I)48, TAF(I)63 and TAF(I)110). We have determined that the human genes TAF1A, TAF1B and TAF1C, encoding these three TAF(I) polypeptides, are localized at lq42, 2p25 and 16q24, respectively. All three genes are present as single copies in the human genome and map to different chromosomes, as shown by somatic cell hybrid panel and radiation hybrid panel analysis and FISH. Two of these genes, TAF1C and TAF1B, are transcribed into multiple RNAs, as determined through Northern analysis of mRNA from various human organs and cell lines. If translated into different polypeptides, this could result in production of variant isoforms of SL1 with different activation potentials.

Alleles↗
PubMed2000

[Difficulties in the clinical, radiological and therapeutic evaluation of the initial stage of mucormycosis of the rhinosinus].

The initial diagnosis and subsequent treatment of rhino-orbital mucormycoses is quite difficult, particularly because the patient may find it difficult to accept aggressive therapeutic protocols, even when free of any endocranial involvement. The authors draw inspiration from a clinical case of rhino-orbital mucormycosis in a patient suffering from decompensated type I diabetes mellitus to discuss the main clinical-diagnostic and therapeutic aspects of this disorder. Timely medical-surgical treatment proves extremely important for prognosis, preventing the intracranial extension of the lesion which is the cause of death in 80% of such cases. As regards the diagnostic protocol, careful clinical, radiological monitoring with CT and NMR--in strict interdisciplinary cooperation between otorhinolaryngologist, radiologist, ophthalmologist, microbiologist and histopathologist--is especially important. Radical surgery, at times demolition, associated with correction of the metabolic decompensation, systemic therapy with Amphotericin B and localbi-weekly medication for three months constitutes the best therapeutic protocol for treatment of this disorder.

Adult↗
PubMed2000

[Prophylactic postoperative radiotherapy in the treatment of supraglottic tumors].

The appropriateness of treatment of supraglottic carcinoma with post-operative radiotherapy is still a controversial issue. The purpose of the present work has been to define the effectiveness of post-operative radiotherapy in the treatment of supraglottic carcinomas and to discuss, on the basis of the data reported in the literature, the usefulness of combined surgery-radiotherapy. The study involved 97 subjects suffering from spinocellular carcinoma of the laryngeal vestibule (95 males, 2 females; average age: 58; age range: 38-89 years) who underwent horizontal supraglottic laryngectomy together with bilateral laterocervical lymph node dissection. Of these patients 35 (36%, group A) had undergone a cycle of prophylactic radiotherapy (60-70 Gy in fractions of 2 Gy/die, administered with two side fields), after surgery. The remaining 62 cases (64%, group B) did not have any additional therapy after surgery. For both groups the overall actuarial survival and 5-year corrected survival rates were calculated; statistical significance was calculated using the Wicoxon test. For group A the overall actuarial survival and corrected actuarial survival rates were, respectively, 74% and 90%. For group B these rates were, respectively 61% and 80%. A statistical comparison of both parameters did not show any statistically significant difference (p = 0.2 and 0.4, respectively). In reference to tumor extension, established both on the basis of clinical (T) and surgical-anatompatholgical (pT) findings, no significant differences were encountered between the overall actuarial survival and corrected actuarial survival rates for the two groups of patients (p > 0.05). In NO patients significantly higher overall actuarial survival rate in those patients who underwent the combined surgery-radiotherapy treatment than in those treated with surgery alone (p = 0.01) was seen. This was not, however, confirmed by the corrected actuarial survival rates and comparative analysis of the groups for surgical staging of the lymph node metastases (p > 0.05). Most likely the different behavior seen in the two groups depends on possible errors in the clinical staging of N due to the presence of reactive lymphadenitis and micrometastases. In conclusion, the data derived from the present research indicate that post-operative radiotherapy, performed as prophylaxis in cases undergoing supraglottic laryngectomy does not yield any statistically significant improvement in prognosis. Therefore, the radiotherapy association should be ruled out in those patients where the oncological radicality of the surgery is reasonably certain. It can possibly be considered as integration to surgery, only in those cases where radicality is in doubt.

Adult↗
PubMed1999

The mouse aldehyde oxidase gene: molecular cloning, chromosomal mapping and functional characterization of the 5'-flanking region.

In this article, we report on the chromosome mapping and molecular cloning of the genetic locus encoding the mouse molybdo-iron/sulfur-flavoprotein aldehyde oxidase. The aldehyde oxidase locus maps to mouse chromosome 1 band C1-C2, as determined by fluorescence in situ hybridization experiments conducted on metaphase chromosomes. The gene is approximately 83 kb long and consists of 35 exons. The exon/intron boundaries are perfectly conserved relative to the corresponding human homolog and almost completely conserved relative to the mouse xanthine oxidoreductase gene. This further supports the concept that the aldehyde oxidase and xanthine oxidoreductase loci evolved from the same ancestral precursor by a gene duplication event. The position of a major transcription start site was defined by primer extension and RNase mapping analysis. The 5'-flanking region of the mouse aldehyde oxidase gene contains a functional and orientation-dependent promoter as well as several putative binding sites for known cell-specific and general transcription factors. Deletion analysis of the 5'-flanking region defines an approximately 470 bp DNA stretch which is necessary and sufficient for the transcription of the mouse aldehyde oxidase gene.

Aldehyde Oxidase↗
PubMed1998

Olfactory groove meningioma with paranasal sinus and nasal cavity extension: removal by combined subfrontal and nasal approach.

A very unusual case of olfactory groove meningioma with recurrence extending into the paranasal sinuses and nasal cavities, 15 years after the first transcranial operation, is described. The patient was successfully treated by a combined subfrontal and nasal approach. Large downward extension of an olfactory groove meningioma into the nasal cavities is a rare event, with no or isolated cases reported even in large series of these tumours. The nasal extent of these meningiomas is more often asymptomatic, although signs of sinus obstruction and epistaxis have been described. Although small paranasal sinus extensions of the meningioma may be removed by the transcranial route, a combined subfrontal and nasal approach is necessary in cases with large tumour masses extending into the nasal cavities, as in our own one.

Adult↗
PubMed1997

Fixity of vocal cords and laryngocele in acromegaly.

Acromegalic patients have a reduced life expectancy mainly due to cardio-, cerebrovascular and respiratory disorders and increased prevalence of neoplasias. Particularly, the pathogenesis of respiratory disorders in acromegalics is debated. Laryngeal abnormalities are not yet well clarified even if they are frequently involved in the occurrence of respiratory insufficiency. In this study, we report on a 65 year-old acromegalic male suffering from frequent and severe dyspnea attacks and clinical findings of respiratory upperway obstruction, besides the common acromegalic features. At the external examination of the larynx, a bilateral painless and soft mass, located in the laterocervical region under the hyoid bone, was detected. Fiberoptic laryngoscopy, showed bilateral swelling between the aryepiglottic fold and the false vocal cords, whose size increased during the expiration and the phonation, fixity of the vocal cords in paramedian position, with a marked reduction of the respiratory space and increase in arytenoid cartilage size and mucosal edema. Neck and mediastinum CT scan showed the presence of an air containing bilateral swelling, crossing the thyrohyoid membrane. Bilateral cricoarytenoidal joint chondrocalcification, associated to a mixed-type bilateral laryngocele, was diagnosed. Laryngoceles were both surgically removed and a left monolateral arytenoidectomy was performed, using fiberoptic microlaryngoscopy with CO2 laser. The clinical evaluation, one month later, confirmed the complete disappearance of dyspnea and a partial improvement of phonation. Three months later, laryngoscopy showed the bilateral restoration of vocal cords motility and a significant improvement of phonation. This case presents an uncommon and severe respiratory problem in acromegaly such as the fixity of vocal cords associated to laryngocele. Circulating GH and IGF-I hypersecretion caused edema and laxity of laryngeal mucosa as well as bilateral ankylosis of cricoarytenoidal joints. The use of CO2 laser technique via micro-laryngoscopy successfully resolved laryngeal abnormalities.

Acromegaly↗
PubMed1997

Compositional mapping of mouse chromosomes and identification of the gene-rich regions.

The mouse genome is a mosaic of isochores, consisting of long (> 300 kb), compositionally homogeneous DNA segments that can be divided into two GC-poor families, L1 and L2, representing 56% of the genome, and two GC-rich families, H1 and H2, representing 26% and 7% of the genome, respectively, the remaining 11% being formed by satellite and ribosomal DNAs. (GC is the molar fraction of guanine + cytosine in DNA.) The mouse genome differs from the human genome (which is representative of most mammalian genomes) because it shows a narrower compositional spectrum of isochores and it has a karyotype formed exclusively by acrocentric chromosomes. The chromosomal distribution of the four isochore families, as investigated here by in situ hybridization of single-copy sequences from compositional DNA fractions, has shown that G(lemsa) bands are essentially composed of GC-poor isochores, whereas R(everse) bands comprise three subsets of bands: R' bands, containing GC-poor isochores and GC-rich isochores of the H1 family, and T and T' bands, containing all H2 isochores (in addition to other isochores), the former containing a higher proportion of H2 isochores than the latter. Mouse T and T' bands are generally syntenic with, and are compositionally related to, human T and T' bands and have the highest gene concentrations. These findings indicate that the distribution of isochore families and genes in chromosomal bands is basically similar in mouse and in human genomes, in spite of their remarkable differences and their extremely large phylogenetic distance.

Animals↗
PubMed1997

T1-T2-T3 glottic tumors: fifteen years experience with CO2 laser.

This research aims at reporting the results of endoscopic treatment of glottic carcinomas by CO2 laser. The cases cited concern 516 patients with glottic T1-T2-T3 carcinomas. The patients have been divided into 5 groups: a) T1a: 194 patients with monolateral carcinoma involving the true vocal cord who underwent simple cordectomy; b) T2a: 104 patients with monolateral cordal carcinoma involving the ventricle and the false cord; c) T1b: 127 cases of monolateral or bilateral carcinoma involving the anterior commissure; d) these patients underwent bilateral cordectomy; T2b: 54 cases of monolateral or bilateral carcinomas involving the anterior commissure and extending to the hypoglottic or supraglottic region; in these patients a bilateral extended cordectomy was performed; e) T3: 37 selected cases of monolateral or bilateral cordal carcinoma with fixed vocal cord, fixity was due to the substantial size of the tumor or to the infiltration of the paraglottic space; these patients underwent a monolateral or bilateral extended cordectomy. The following are the results at 5 years: group a: overall observed survival rate (OSR) was 79% and the adjusted survival rate (ASR) 94.5%; group b: OSR 67% and ASR 77%; group c: OSR 88.4% and ASR 96.5%; group d: OSR 82% and ASR 90%; group e: OSR 55% and ASR 67%. The above data are evidence of the fact that our surgical techniques offer similar or better advantages in terms of survival rate compared to the traditional procedures. It must be noted that endoscopic surgery of glottic tumors carried out by CO2 laser offers relevant benefits when compared with traditional surgery: i) rapidity of operation and reduced surgical trauma; ii) the possibility of avoiding tracheotomy; iii) the respect of the integrity of the cartilaginous skeleton; iv) short postoperative course and low incidence of complication; v) better functional results; vi) a shorter stay in hospital with positive psychological effects on the patients and lower social costs.

Carcinoma, Squamous Cell↗