Search PubMed⌕ Search

Biomedical subjects

F Ottaviani

Publications and source records attributed to F Ottaviani.

At least 19 recordsLinked to original sources
PubMed1992

Innervation of the paralyzed laryngeal muscles by phrenic motoneurons. A quantitative study by light and electron microscopy.

In the cat, inspiratory opening of the paralyzed glottis recovered after unilateral or bilateral reinnervation of the posterior cricoarytenoid (PCA) muscles by phrenic axons. The morphometric analysis of the regenerated recurrent laryngeal nerves (RLNs), showed that proliferation was abundant; 4 months after the nerve anastomosis, more than 500 myelinated axonal branches repopulated the RLNs. The mean diameter of motor axons (3.5 to 5.0 microns) was lower than in normal phrenic and RLN (8 to 10 microns), and the mean internode length was about half that of the normal RLN. Histochemical examination of the PCA muscle revealed that muscle fiber composition (44% type I and 56% type II muscle fiber) was fairly similar to that of normal PCA. The contraction time of the reinnervated muscles was as long as 60 msec at the time of movement recovery, but it shortened to 25 to 30 msec when the reinnervation time increased. These anatomical and functional results support the choice of the phrenic nerve for laryngeal reinnervation.

Adenosine Triphosphatases↗
PubMed1991

Interference of cephalosporins with immune response: effects of cefonicid on human T-helper cells.

To determine the immunosuppressive effect(s) of cephalosporin cefonicid (CEFO) on human T-helper cells (Th), we exposed human peripheral blood mononuclear cells (PBMC) to various concentrations of CEFO during in vitro stimulation with a panel of T-lymphocyte stimulators that activate different Th/antigen presenting cell (APC) pathways. We evaluated the proliferation and IL-2 production induced by influenza virus (FLU), allogeneic lymphocytes (ALLO), xenogeneic mouse splenocytes (XENO) or phytohemagglutinin (PHA). The proliferative responses to FLU and XENO were much more depressed by CEFO than those to ALLO or PHA. After 7 days of culture with the highest dose of CEFO tested (200 mg/l) the stimulation index (stimulated/unstimulated culture) was near to 0 in FLU and XENO treated cultures, indicating that the response against these antigens was completely abrogated. The responses to ALLO and PHA were also impaired, but not abrogated (stimulation index greater than 1). Since FLU and XENO utilize the CD4+ Th/self-APC pathway our data suggested that this pathway was extremely sensitive to CEFO-induced inhibition both when the response requires memory Th cells (FLU) and virgin Th cells (XENO). The incubation with CEFO (200 mg/l) reduced the IL-2 production by XENO, FLU and ALLO to less than 20% of control cultures, while paradoxically increases to 120% the production by PHA.

Antigens↗
PubMed1990

Vocalization-related stapedius muscle activity in different age chickens (Gallus gallus), and its role in vocal development.

The stapedius muscle activity associated with vocalization was analyzed in young and adult roosters. Our results show that remarkable differences in the behavior of vocalization-related stapedius muscle activity exist between these two ages. Unlike young roosters, electrical stimulation in the midbrain of adult cocks yields vocalizations associated with stapedius muscle EMG responses that always show a higher threshold and a longer latency than those of the vocalization induced. Moreover, the maximal amplitude of the stapedius muscle EMG response is consistently lower than that detected in young roosters, despite the fact that the maximal vocalization amplitude of the adult birds is much higher. On the whole our results demonstrate that vocalization-related stapedius muscle activity is strongly reduced in adulthood. The possibility that stapedius muscle may play a role during the vocal development was verified by comparing the crow of normal roosters with that of cocks from which the stapedius muscle had been removed shortly after hatching. Strong differences exist in the amplitude/frequency distribution of the crowing of normal and stapedectomized roosters, suggesting that the stapedius muscle exerts an important role in auditory feedback modulation, and that this feedback is used for normal vocal development.

Aging↗
PubMed1990

Marijuana smoking as a possible cause of tongue carcinoma in young patients.

A case of T1N0M0 carcinoma of the tongue in a male 23-year-old 'regular' marijuana smoker is described. Hemiglossectomy and complete bilateral neck dissection were carried out. No post-operative radiotherapy was given as the resection margins were histologically negative. The tumour recurred one year later in the left cervical region involving the mandible and surgery was again performed, but after three months, neck disease was still evident. The case described case implies the introduction of marijuana as a possible new risk factor in the development of oral cavity tumours. Resection of the primary lesion has to be as wide as possible even in T1 cases, due to the aggressive biological behaviour of such tumours in young subjects.

Adult↗
PubMed1990

Auditory brainstem responses in the aged.

The auditory brainstem responses (ABR) in a group of 74 aged subjects (60-80 years), affected by presbycusis were evaluated for presence of a retrocochlear involvement. The comparison of results from subjects with presbycusis with those from normally-hearing elderly subjects, and young subjects, affected by a cochlear sloping hearing loss, revealed that the latency increase of ABR observed in presbycusis is mainly correlated to the audiometric shape of the hearing loss and not to age per se.

Acoustic Impedance Tests↗
PubMed1990

Auditory steady-state responses in the rabbit.

The authors have studied auditory brainstem (ABRs), middle latency (MLRs) and steady-state potentials (SSRs) in 15 adult male rabbits weighing between 2.5 and 3 kg in order to verify if SSRs are due to a mere superimposition of ABRs and MLRs or to a resonance phenomenon. Ten of them were awake while 5 were studied under urethane anesthesia. Acoustic stimuli consisted in 0.1-ms square-wave pulses delivered at presentation rates ranging between 1 and 80/s at a stimulus intensity of 80 dB p.e. SPL. Our data show that reliable auditory SSRs can be obtained in the rabbit at a presentation rate of 30 stimuli/s, probably due to the superimposition of ABRs and MLR Pb waves which show an interwave interval of about 35 ms. The nonlinear aspects which can be detected are probably due to the effect of decreasing interstimulus intervals on the duration and amplitude of the Pb wave. It can then be concluded that SSRs in the rabbit are due more to a superimposition of ABR and MLR waves than to a resonance phenomenon.

Acoustic Stimulation↗
PubMed1990

40-Hz steady-state responses in newborns and in children.

The authors investigated the 40-Hz steady-state responses (SSR) in 32 full-term newborns and in 10 normal children (5-8 years old), using 500-Hz tone bursts. The 40-Hz SSR threshold is located at about 50 and 30 dB nHL in newborns and older children, respectively. The latencies of both P1 and N1 waves decreased significantly with age, while the amplitudes increased. No significant latency and amplitude intersex differences have been observed. Moreover, with age, the 40-Hz SSR became more stable, their test-retest replicability improved, and P1-N1 wave occurrence increased. The authors finally discuss the possible underlying mechanisms of these findings and conclude that the 40-Hz SSR are difficult to obtain and are scarcely reliable in defining the low-frequency threshold in newborns. The stability and reliability of the responses increase with age, and the electrophysiological and behavioral thresholds to low-frequency stimuli tend to overlap.

Audiometry, Evoked Response↗
PubMed1989

Recovery of inspiratory abduction of the paralyzed vocal cords after bilateral reinnervation of the cricoarytenoid muscles by one single branch of the phrenic nerve.

The aim of this study was to provide the bilateral reinnervation of the posterior cricoarytenoid (PCA) muscles by the superior root of the right phrenic nerve. In six adult cats, the right phrenic root was anastomosed to the distal stump of the transected recurrent laryngeal nerve (RLN) on the same side. The RLN adductor branch was then cut and anastomosed to a nerve graft whose end was carried contralaterally and sutured to the left RLN or to the left PCA muscle. The phrenic fibers regrowing along the RLN abductor branch reinnervated the right PCA muscle and restored the inspiratory abduction of the right vocal cord in all the animals. In five of the six cats, the fibers regenerated through the RLN adductor branch and the graft reached the left PCA muscle and also restored the inspiratory opening of the larynx on the left side. Histological nerve examination revealed a fairly symmetrical distribution of the regenerated phrenic axons to the right and left PCA muscles.

Anastomosis, Surgical↗
PubMed1986

Auditory brain-stem (ABRs) and middle latency auditory responses (MLRs) in the prognosis of severely head-injured patients.

Auditory brain-stem responses (ABRs) were studied in 66 subjects with severe head trauma. Middle latency responses (MLRs) were also recorded in 22 of them. Patients were carefully selected to avoid conditions such as pre-existing or acute deafness, hypothermia or ethanol intoxication. In order to evaluate the usefulness of potentials in predicting recovery, patients were classified according to the Glasgow Coma Scale (GCS). ABR tracings were classified into 5 groups and MLR into 2 groups. The recovery was good in the presence of a type 1 ABR, poor in the presence of types 3, 4 and 5. Concerning type 2 ABR, the outcome is related to the MLR type, and to the presence of an electrophysiological improvement within the first 3 months following trauma. The reliability of ABR and MLR in predicting the outcome of severe head injury appears to be greater than other usually considered clinical and instrumental data (age, GCS, CT scan, EEG).

Adolescent↗
PubMed1976

[Determination of CPK isoenzymes by column chromatography (author's transl)].

The AA. have carried out in patients affected by proved myocardial infarct, by other cardiac diseases and by muscular dystrophy the following enzymes determinations: total CPK, total LDH, SGOT, SGPT, HBDH, CPK isoenzymes by column chromatography (Mercer's method) and LDH isoenzymes either by column chromatography (Mercer's method) and by electrophoretic separation. Some results concerning the appearance of the CK-MB isoenzymes during the acute period of the myocardial infarction are described.

Adult↗
PubMed1976

[Platelets aggregation employing ADP and cephalin. Comparative tests (author's transl)].

The AA. have carried out researches into the results of the platelets aggregation test (PAT) on 375 people by use of the Born method; they have employed ADP and a commercial available cephalin (Thrombofax, Ortho). In the first case the parameters taken into consideration are: the minimum dose of ADP able to cause a "double wave aggregation", the slope and the maximum increase in light transmission; in the second case the parameters considered are: the latency period, the maximum speed and the maximum amplitude. The normal values, in 75 persons, are: --6 +/- 2 X 10(-7)M (min dose wor "double wave"); --15,5 +/- 4,9 UT/min (slope); -- 46,3 +/- 6,8 UT (max increase in light transmission); regarding ADP aggregation. --90 +/- 40 sec (latency period); -- 30 +/- 15 UT/min (max speed); -- 52 +/- 4,63 UT (max amplitude); relating to Thrombofax aggregation. Analyses of PAT, by parallel using both aggregating agents, have been made on 260 women undergoina an oestrogen-progestative therapy, on 25 daibetic subjects and on 15 subjects undergoing an anti-aggregation oral therapy (Ageroplas, Serono, Roma). The AA. stress on the validity of ADP as an aggregation agent in routine tests, while Trombofax has revealed itself to be not very sensitive in all the cases with hyperaggregation. However it is to be noted that use of cephalin results interesting in tests made on subjects undergoing an anti-aggregation therapy, as the PAT parameters seen proportional to the quantity of the drug given to the patient, which is just the opposite of what happens with ADP.

Adenosine Diphosphate↗
PubMedDate not supplied

[The restoration of the vocal possibilities for the laryngectomized patient with a tracheoesophageal prosthesis].

The experience reported concerning vocal rehabilitation employing tracheoesophageal prostheses (TEP) in laryngectomized subjects at the University of Milan is based upon 149 patients who underwent procedures for total laryngectomy from November 1986 on in nearly all cases (137), a primary procedure was followed in order to insert a Blom Singer prosthesis. Some technical modifications in creating the fistula during the reconstruction phase of laryngectomy reduced the number of postoperative and local complications of the fistula. The men phoniatric rehabilitation time is 38 days from the procedure. The most important aspects affecting the length of rehabilitation are the presence of lower respiratory tract disorders and contemporaneous postoperative radiotherapy. The mean lifetime of the prostheses is 92 days, the main restricting factor being the care taken by the patient. Microbiological studies showed the virtually constant association between fungi and Pseudomonas sp. Nevertheless, infection of the fistula and forced removal of the prosthesis occurred only in 1 patient. Other complications were as follows: granulation tissue at the tracheal side of the fistula into the trachea or oesophagus, 6 and 1 respectively; enlargement of the fistula, 5; others, 15. Fifteen percent of the patients does not succeed in achieving a tracheoesophageal voice because of respiratory insufficiency, difficult neuromuscular control or psychological problems.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchi↗
PubMedDate not supplied

[Carotid body tumors: the clinical, diagnostic and therapeutic aspects].

The authors discuss the epidemiology, histology, symptomatology, diagnosis and therapy of carotid body tumors, basing their discussion on three personal observations and on a case of cervical dermatocyst which showed clinical and radiological data consistent with diagnosis of a glomus tumor. Chemodectomas of the neck are more often seen in the carotid body and are considered histologically benign, although they might induce local or distant metastases. Clinical presentation is often non-specific and may only consist in a slowly growing mass in the higher jugular-carotid region. Among the various imaging techniques (CT, MR), supra-aortic selective angiography, including digital subtraction techniques, is now considered the most reliable tool, while ultrasonography and gammagraphy with 99mTc-gluconate or 131I-MBG are recommended for screening and family testing purposes. Biopsy is to be avoided as it is very likely to cause massive bleeding and because of the high percentage of false negatives. Surgery is the choice treatment, and lateral cervicotomy is the recommended approach for exeresis of the mass, while radiotherapy should be planned in patients with precise contra-indications for surgery and when the tumor mass has already reached the skull base. Pre-operatory selective embolization is still controversial.

Adult↗
PubMedDate not supplied

[Ectopic thyroid gland].

Based upon the observation of four cases of ectopic lingual thyroid the authors discuss the etiopathogenetic, clinical-diagnostic and therapeutic aspects of this pathology. The clinical characteristics of the mass, scintigraphy, echography and CT scan of the neck, the T3, T4, TSH doses in the blood and fine needle aspiration of the mass have made adequate appraisal of its possible nature and have led to the identification of the presence of thyroid tissue in other sites. In regard to therapy, the authors believe that surgery is compulsory for patients showing clinical signs of upper airway obstruction despite suppressive therapy or when the lesion shows signs of malignant degeneration. After having mentioned the more commonly employed surgical approaches, emphasis is placed on median pharyngotomy as it permits the best visualization of the region, a careful excision of the mass and a valid control over bleeding. In most cases a tracheotomy proves unnecessary. The post surgical hormonal situation suggests the opportunity of a possible substitutive therapy with synthetic hormones or thyroid derivatives.

Adolescent↗
PubMedDate not supplied

[Brain mapping of middle latency auditory potentials in normal subjects].

The MLRs of 20 normal hearing adults were recorded by cerebral mapping. In regard to the Pa and Na waves, it is suggested that two different generation sites exist because of the different spatio-temporal distribution of the waves over the scalp. It is demonstrated that amplitudes measured by the "grand average" technique are constantly lower than those obtained with the manual determination, and they conclude that manual determination represents the most reliable method in order to calculate waves amplitude. Finally, it is suggested that, due to the different generation sites for Pa and Na waves and to the uneven distribution of the Na wave over the scalp, Pa amplitude should be measured from the baseline and not from the Na negative deflection. Moreover, in 14 cases, when one ear was stimulated the Pa wave obtained at most recording points was significantly larger than the one recorded contralaterally.

Acoustic Impedance Tests↗
PubMedDate not supplied

[Infantile autism].

Explore the source record for details and available documents.

Autistic Disorder↗
PubMedDate not supplied

[Influence of static stimulation of cervical and otolithic receptors on posturographic parameters].

In the present work 30 normal adult subjects (20 males, 10 females; age range 25-40 years) having no signs or symptoms of vestibular involvement were studied in order to verify whether posturographic parameters could be influenced by the static stimulation of cervical and otolithic receptors. The posturographic evaluation was carried out using a stabilometric platform (Bertec) with the subject standing and the head in one of the following positions: median position, turned left (45 degrees), turned right (45 degrees), tilted left (40 degrees), tilted right (40 degrees), with eyes both opened and closed. The data obtained indicate that wide standard deviations exist in the observed parameters and no significant changes were observed with the head turned either to the right or left nor with the head tilted in either direction. Moreover, the posturographic data obtained with eyes open were slightly reduced in comparison to those obtained with the eyes closed. One can, thus, conclude that neither cervical nor otolithic inputs influence posturographic parameters under static conditions, while visual inputs modify significantly posturographic data, except the coordinates of the foot center of pressure.

Adult↗