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S Motta

Publications and source records attributed to S Motta.

At least 37 records · Page 2Linked to original sources
PubMed1996

Genomic localization of the human gene encoding Dr1, a negative modulator of transcription of class II and class III genes.

Dr1 is a nuclear protein of 19 kDa that exists in the nucleoplasm as a homotetramer. By binding to TBP (the DNA-binding subunit of TFIID, and also a subunit of SL1 and TFIIIB), the protein blocks class II and class III preinitiation complex assembly, thus repressing the activity of the corresponding promoters. Since transcription of class I genes is unaffected by Dr1. it has been proposed that the protein may coordinate the expression of class I, class II and class III genes. By somatic cell genetics and fluorescence in situ hybridization, we have localized the gene (DR1), present in the genome of higher eukaryotes as a single copy, to human chromosome region 1p21-->p13. The nucleotide sequence conservation of the coding segment of the gene, as determined by Noah's ark blot analysis, and its ubiquitous transcription suggest that Dr1 has an important biological role, which could be related to the negative control of cell proliferation.

Animals↗
PubMed1996

Aerodynamic study of velopharyngeal insufficiency before and after logopedic treatment.

The aerodynamic bases of articulatory defects which characterize velopharyngeal insufficiency are not yet well defined. The purpose of our investigation has been to establish the type and the severity of aerodynamic alterations correlated with this syndrome before and after logopedic treatment; thus we have exposed the phoneme magnitude of pi:/, produced by 20 control individuals and by 12 patients with velopharyngeal insufficiency, to an aerodynamic study by means of a computerized system (Aerophone II, FJ Electronics) able to record, at the same time, phonatory airflow, intraoral pressure, and sound intensity. The data collected were subjected to statistical analysis by using Student's t test. The results obtained before logopedic treatment documented: (1) a remarkable articulatory distortion during the implosion of magnitude of p by a two-phasic pressure wave with a reduced amplitude compared to the one registered in control group subjects (7.3 +/- 2.8 cm H2O vs. 10.9 +/- 2.7 cm H2O; mean +/- SD; p < 0.01); (2) the presence of a nasal airflow in this same phase (0.13 +/- 0.07 liters/s); (3) peak airflow relative to the explosion of magnitude of p inferior to the one recorded in the control group (0.41 +/- 0.08 liters/s vs. 0.57 +/- 0.11 liters/s; p < 0.01); (4) a mean ratio between the duration of the implosive phase of magnitude of p and that of whole articulatory cycle inferior to the value recorded in the control group (34.8 +/- 2.6% vs. 39.2 +/- 2.3%; p < 0.01). At the end of logopedic treatment the aerodynamic investigation allowed to correlate the improvement of the speech defects due to rehabilitation to precise aerodynamic data: (1) a monophasic pressure wave with a peak (14.9 +/- 4.7 cm H2O) that is higher than the one observed in the control group (p < 0.01) and the one observed in the control group (p < 0.01) and the one observed in patients before therapy (p < 0.01); (2) a significant reduction of the nasal airflow recorded before logopedic treatment (0.04 +/- 0.04 liters/s; p < 0.01); (3) a remarkable increase in peak airflow compared to the one recorded before logopedic treatment (0.93 +/- 0.25 liters/s; p < 0.01); (4) a further reduction of the mean percentage ratio between the duration of the implosive phase of magnitude of p and that of the whole articulatory cycle (29.2 +/- 2.0%; p < 0.01) as compared to the one recorded before logopedic treatment. The results of our investigation underline how many different aerodynamic factors are involved in the pathogenesis of articulatory defects of speech related to velopharyngeal insufficiency, and how they reciprocally interfere; furthermore, our data indicate that logopedic treatment does not always restore physiological conditions, but often facilitates the realization of particular articulatory strategies which are not found in normal conditions.

Child↗
PubMed1996

[The small fenestra vs large stapedectomy: comparative evaluation of failures and complications].

The Authors discuss post-operative failures and complications detected in their case-report of 1857 patients, operated for otosclerotic disease between 1982 and 1993 (399 large fenestra and 1458 small fenestra stapedotomies), with reference to the data from international literature. Their study reveals that the most frequent clinical event caused by complications arising is still hypoacusia of various degree, both conductive (2.7%) and sensorineural (6.6%); more precisely, conductive hearing loss points to revision surgery, while sensorineural lesions, often limited to high frequencies (5.7%), may unfortunately take the form of anacousia (0.9%). Some extra-auditory complications (temporary facial paralysis, ear drum perforation, disgeusia, tinnitus) are also present with relative frequency in stapes surgery (4.2%); among them, however, only impairment or appearance of tinnitus (0.6%) turn out to be a persistent disorder. Analysis of the results underlines that the complications rate is higher in the case of coexisting morphological anomalies (such as stenosis of the external ear canal, disjointing or amputation of the incus, difficulty in approaching the oval window, reobliteration of the oval window, facial nerve prolapse) or when intraoperative problems arise (excessive bleeding, profuse perylymph flow), which make the operation more difficult to perform. The data obtained in this study show that stapedotomy (using a 0.6 mm diameter prosthesis), gives a significantly lower rate of sensorineural complications (4.1%), than platinectomy (15.6%), because of the reduction of labirinthine traumatism. Lastly, the Authors performed 64 revision operations, evaluating intraoperative findings and hearing recovery rate. Causes of failure most frequently detected during revision surgery were: incus necrosis (24.6%) and prosthesis displacement (21.3%) with possible reobliteration of the oval window (23%); however it has not always been possible to detect pathogenesis of a postoperative conductive hearing loss. All things considered, results of revision surgery seem to be less satisfactory (56% improvements, 4.9% severe sensorineural hearing loss) than those obtained after the first operation.

Humans↗
PubMed1996

[Stapedotomy vs stapedectomy. Comparison of hearing results].

The Authors investigated 200 patients, selected at random from an operative case-report of 1857 subjects, in order to evaluate hearing results of stapes surgery and to compare the recovery obtained using both small (0.7 mm footplate hole) and large fenestra stapedectomy. More precisely, after 1 week and 6 months, they examined audiological findings (air, bone conduction and cochlear reserve) before performing the operation in order to evaluate the following problems: persisting conductive gap at low frequencies, sensorineural hearing loss at high frequencies, prognosis in advanced stages (compromised pre-operative bone conduction), preservation of hearing over time. Firstly, data from our research indicate extremely successful results in stapes surgery; in particular, hearing improvement seems to be more frequent for middle-low tones (in 98% of patients), due to the higher rate of sensorineural deficit at high frequencies, which are however characterized by a more complete closure of the conductive gap. However with stapedotomy better hearing recovery is obtained and in a greater number of patients with a lower evidence of bone conduction impairment. Such an advantage increases even further from the time of surgery (p significant after 6 months on every frequency) and particularly in cases where disease is advanced.

Adult↗
PubMed1995

Evaluation of cytogenetic effects of a naturally occurring non-ice-nucleation Pseudomonas fluorescens strain in Chinese hamster ovary (CHO) cells.

One of the main methods for eliminating ice-nucleation-active (INA+) bacteria the micro-organisms responsible for frost injuries to plants at mild freezing temperatures, is the use, as competitors, of other naturally occurring non-nucleating strains (non-INA). In the present article we investigated the cytogenetic effects of a naturally occurring non-INA strain of Pseudomonas fluorescens (MS 1640 R3), evaluating the induction of chromosomal aberrations and sister chromatid exchanges (SCEs) in Chinese hamster ovary (CHO) cells in the absence and presence of rat S9 metabolism. The results obtained did not show any increase in either chromosomal aberrations or SCEs, both in the absence and presence of rat S9 metabolism when used as i) intact bacteria cells, ii) sonicated bacteria (i.e., potential endotoxins), or iii) metabolic bacterial products (i.e., potential exotoxins) released in the growth medium.

Animals↗
PubMed1995

Regional localization of the human EGF-like growth factor CRIPTO gene (TDGF-1) to chromosome 3p21.

The CRIPTO gene encodes a novel human growth factor structurally related to epidermal growth factor. We localized the CRIPTO gene to chromosome 3p21 by fluorescence in situ hybridization with a cosmid clone containing 40 kb of the CRIPTO genomic region (TDGF-1). To suppress hybridization to CRIPTO-related sequences, present in multiple copies in the human genome, hybridization was carried out in the presence of unlabeled CRIPTO cDNA in excess over the probe. Our finding confirms the provisional mapping of the CRIPTO gene to chromosome 3, and assigns it precisely to a chromosomal region involved in several rearrangements occurring in malignancy.

Chromosome Mapping↗
PubMed1995

Genetic characterization of general transcription factors TFIIF and TFIIB of Homo sapiens sapiens.

Analysis of loci GTF2F1 and GTF2B, encoding Rap 74 (a subunit of TFIIF) and TFIIB, respectively, showed that they are present in a single copy in the human genome and are localized at 19p13.3 and 1p22, respectively. By using as probe a cDNA for Rap 30 (the other subunit of TFIIF), we localized the GTF2F2 locus to 13q14; the same probe also detected a cross-hybridizing sequence at 4q31 whose functional importance remains to be elucidated. These data and those previously published by our group demonstrate that genes coding for class II general transcription factors with reported sequence similarity to bacterial sigma proteins are scattered in different regions of the human genome, with no evidence of clustering. This dispersion and the identification of homologs of both TBP and TFIIB in Archaea suggest an early evolutionary origin of the general transcription apparatus of contemporary eukaryotes.

Animals↗
PubMed1995

[The treatment of allergic vasomotor rhinitis: diagnostic problems and local immunotherapy].

Treatment of allergic vasomotor rhinitis is to be regarded with the factors that modify the symptomatology. In fact must be considered the morphological changes (septum deviation, adenoids, turbinates hypertrophy, polyps) infections (bacteria, chlamydiae, micetes) and specific allergens. Identification of allergens and sensitization threshold is to be studied; then specific hyposensitization will be assessed. In the present study, 68 subjects having nasal reactivity have been observed and underwent to different ways of treatment: 18 with permanent stenosis identified by rhinomanometry and not modified with vasoconstrictors were operated; 25 of the 50 patients with normal nasal cavities showed contemporary infections: after a specific antimicrobic or antimycotic treatment, a clear improvement was obtained documented by rhinomanometry before and after nasal stimulations. The 50 patients with normal morphology underwent a local hyposensitization against the allergens. As a matter of fact: a) in all cases a clear improvement was obtained in phase of increasing; b) after one year of maintainance just 13 over 50 (26%) returned to previous conditions. The Authors remark how local immunotherapy by the nasal way give good possibilities in a high percentage of cases in the following conditions: correct clinical evaluation, especially concerning the identification of factors determining vasomotor rhinitis; employment of precise techniques for diagnosis; observation of clinical data and results turning out from instrumental investigations, especially concerning the nasal provocation test evaluated by rhinomanometry.

Humans↗
PubMed1995

[The use of hearing aids in children with profound deafness. Methodology and results].

The early application of hearing aids in children with severe and profound hearing loss is rather an hard problem that has to be solved, according to the Authors, by taking care of several factors. Usually, as far as these patients concern, two kinds of hearings aids are used. The first one emphasizes all the frequencies in the same way, including low tones that, in the early ages, are very important for improving prosodic pattern, occlusive and liquid phonemas, primary words and sentences. The second type, emphasizing only medium and high frequencies, is useful for discrimination processes. The Authors suggest to applicate the hearing aids in these patients, following a behavior be themselves named "dynamic application". In the first phase the Authors use hearing aids emphasizing also low tones; in the second one they modify the device, according more precise data turning out form audiometric evaluation and speech therapy. The results concerning a research on 27 children with profound hearing loss are debated; the application of hearing aids occurred in early age and the speech therapy followed the same criteria for all patients. The subjects were divided in two groups, homogeneous for age, degree of hearing loss and social environment. For the 12 children of groups A the "dynamic application" was used. For the 15 patients of group B the traditional strategy, using only devices for the amplification of medium and high tones, was applied. The best results concerning voice intonation and learning occlusive phonemas were obtained in group A subjects. The Authors, introducing their results and discussion, compare them with references data. In conclusion, the "dynamic application" is effective because of the better results in speech therapy and also because its ratio permits the application of hearing aids in children with hearing loss of different degrees, especially in the most difficult cases.

Child↗
PubMed1995

[The treatment of benign laryngeal pathologies using CO2 laser in direct microlaryngoscopy with propofol-induced endovenous anesthesia in spontaneous respiration without intubation].

Direct microlaryngoscopy is an endoscopic technique with considerable diagnostic and surgical potentialities, which are increased when carbon-dioxide Laser is used, but often limited by the anaesthesiologic methods employed. In fact, the traditional anaesthesiologic technique, which uses small bore oral-tracheal tubes and provides good ventilation, has significant disadvantages: the tube often impedes surgical activity especially in the posterior regions of the larynx; stenoses of the larynx impede oral-thacheal intubation and thus require pre-operatory thacheotomy; administration of succinylcholine often induces diffused myalgia in the following 12-24 hours; administration of traditional narcotics always requires hospitalization. Jet-ventilation used by the Freach School as an alterative, while offering a more ample operatory space, is also accompanied by many disadvantages: vocal cords vibration; spray expulsion of smoke, blood, etc.; as with the traditional method, it cannot be employed in cases of laryngeal stenoses; succinylcholine often induces diffused myalgia; it cannot be used on out-patients. Introduction of Propofol, a new endovenous anaesthetic, the anaesthetologic pratice has permitted total endovenous anaesthesia to be achieved, in spontaneous respiration, without intubation. This method is indicated even in cases where the previously mentioned approaches are shown to be inadequate or impracticable. Narcosis with Propofol was used in 70 patients with benign laryngeal pathologies, belonging to the ASA risk classes I-II who underwent surgery via CO2 Laser during Microlaryngoscopy. The pharmacologic protocol of this narcosis require intravenous premedication with atropine and phentanyl, induction and continuation with Propofol and pharyngolaryngeal local anaesthesia with lidocaine spray. The advantages offered by this method are considerable: a completely free operative space; the possibility of being used in cases of laryngeal stenosis; a rapid return to consciousness; the absence of myalgia after surgery; the possibility of treating the disease on an out-patient basis. The absence of significant complications and the good results obtained lead us to propose this anaesthesiologic method as a valid alternative to anaesthesia by the traditional oral-tracheal intubation and to Jet ventilation.

Adult↗
PubMed1994

Localization of the human genes encoding the two subunits of general transcription factor TFIIE.

TFIIE is a general transcription factor for class II genes composed of two types of subunits, a large one of 56 kDa and a small of 34 kDa. By Southern analysis at high and at low stringency of a panel of mouse/human hybrid cell lines and by in situ chromosomal hybridization, we have demonstrated that both polypeptides are encoded by genes that are single copy in the human genome and are localized at 3q13-q21 and at 8p12, respectively. A TaqI RFLP (heterozygosity index of 0.07) was detected at the locus for the 56-kDa subunit.

Animals↗
PubMed1994

Physical mapping at 6q27 of the locus for the TATA box-binding protein, the DNA-binding subunit of TFIID and a component of SL1 and TFIIIB, strongly suggests that it is single copy in the human genome.

The TATA box-binding protein (TBP) has a fundamental role in eukaryotic cell metabolism, since it is necessary for transcription of class I, class II, and class III genes; in fact, TBP is the DNA-binding subunit of TFIID and a component of SL1 and TFIIIB. Contrary to the previously hypothesized existence of a family of genes coding for DNA-binding proteins highly related to TBP, our experiments show that the segment coding for the evolutionarily well-conserved carboxyl-terminal domain, involved in DNA binding, is unique; accordingly, we conclude that the TBP locus itself, which we have localized to 6q27, is single copy in the human genome. On the other hand, a cDNA fragment coding for the evolutionarily variable amino-terminal domain detects multiple cross-hybridizing sequences in the genome of higher eukaryotes. We suggest that the common motif is represented by the long string of glutamine codons, which characterizes the amino-terminal segment of human TBP: in fact, other proteins involved in transcription, such as TAF II 110, Sp1, and some homeobox proteins, are known to contain glutamine-rich segments.

Animals↗
PubMed1994

Immunoactivity of pidotimod against episodes of recurrent tonsillitis in childhood.

The therapeutic efficacy of the synthetic immunostimulant pidotimod ((R)-3-[(S)-(5-oxo-2-pyrrolidinyl) carbonyl]-thiazolidine-4-carboxylic acid, PGT/1A, CAS 121808-62-6) was evaluated in a double-blind placebo-controlled study in parallel groups in the management of recurrences in 235 children with recurrent tonsillitis. The ambulant study provided for 15 days of treatment with two oral vials of pidotimod 400 mg or placebo daily, in accordance with a randomisation list, 60 days of treatment with one oral vial of pidotimod 400 mg or placebo daily, and a 90-day follow-up period. The total trial period was 165 days. In addition to evaluating the number of tonsillitis recurrences which occurred during the 75 days of treatment and the 90-day follow-up period, the number of days on which the principal symptoms of the illness were present and on which drugs such as antibiotics or anti-inflammatory agents were used concomitantly, as well as the number of days' absence from school, were analyzed. The findings showed that, taking the treatment phase and the three-month follow-up period together, pidotimod significantly reduces the incidence of inflammatory upper airways episodes. The very low incidence of adverse effects, which was the same as that in the placebo group, confirmed the excellent safety of the product.

Adjuvants, Immunologic↗
PubMed1994

Interlamellar lipid differences between normal and psoriatic stratum corneum.

Intercellular lipids of the stratum corneum are involved in permeability barrier integrity and function. In psoriasis, desquamation and permeability barrier homeostasis are modified; these observations are consistent with an alteration in stratum corneum lipid production. Therefore, in the present study, we determined and compared the total content of the three main intercellular lipids in psoriatic scales and normal human stratum corneum. Our results showed that the relative free fatty acid content decreased remarkably (46%) in psoriatic scales, compared with normal human stratum corneum. This decrease may reflect a general state of emergency of keratinocytes, in which free fatty acids can be employed.

Ceramides↗
PubMed1994

Abnormality of water barrier function in psoriasis. Role of ceramide fractions.

BACKGROUND AND DESIGN: In psoriasis the formation of the cornified layer is deranged and water flux is reportedly increased. We investigated three different forms of psoriasis: transepidermal water loss was measured on uninvolved skin and psoriatic plaques; lipids from plaques were extracted; and ceramide distribution in scale vs normal stratum corneum was compared. Moreover, the lipid biochemical results were compared with transepidermal water loss rates in the same lesions. To assess potential alteration in ceramide distribution, lipids from both psoriatic scale and normal stratum corneum were extracted by the Bligh-Dyer method, separated on high performance thin layer chromatography plates, and quantified by computerized densitometry. Water flux was measured as transepidermal water loss using an evaporimeter; results between uninvolved and involved psoriatic skin and age-matched control skin were statistically evaluated. RESULTS: In comparison with normal stratum corneum, psoriatic plaque ceramides showed a different distribution; in particular, ceramide 1 was significantly decreased. The increased transepidermal water loss values of psoriatic plaques vs control skin and between psoriatic involved vs uninvolved skin were significant. CONCLUSION: Our findings indicate that in psoriasis the altered ceramide distribution can be linked specifically to the defect in keratinocyte differentiation; the defect in skin barrier function may be attributed largely or in part to ceramide 1 reduction.

Ceramides↗