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Biomedical subjects

A Moretti

Publications and source records attributed to A Moretti.

At least 109 records · Page 6Linked to original sources
PubMed1995

[Widened forwarding total laryngectomy ("squared laryngectomy"). Hints of surgical techniques and personal experience].

Primitive T4 laryngeal neoplasms with anterior invasion and neoplasm recurring after partial and subtotal intervention often invade the soft prelaryngeal tissues and in these cases the neoplastic illness can be no longer be controlled be "organ surgery". The widened forwarding total laryngectomy, "squared" or "carrè" laryngectomy according to some Authors of French School, is a surgical procedure not "on an organ" but "in an area" or "region" which proposes to delete, in one step, the larynx, the bone hyoid, the fasciae and the prelaryngeal muscles, the thyroid gland and, if necessary, a more or less large quantity of anterior cervical skin. If the removal involves a vast cutaneous area, it is necessary to mend the loss of substance by wrapping around a miocutaneous flap of pectoralis mayor muscle. In the last five years, 4 male patients, between 48 and 73 years, were treated with widened forwarding total laryngectomy. They were all carriers of epidermoid laryngeal carcinomas with various degrees of differentation: primitive in one patients, recidivist after performance of partial (cordectomy) and subtotal (two Labayle) surgery in the other three patients. In the only case of T4 primitive laryngeal neoplasm it was necessary to carry out a functional neck dissection bilaterally. Loss of substance always required the use of a miocutaneous flap of pectoralis mayor muscle except in one patient in which the removal of the prelaryngeal tissues was limited and therefore it was possible to make a direct seam. We always completely removed the thyroid gland, the prelaryngeal muscular system and skin of the preceding stomy (in the Labayle) sparing, on the other hand, the hyoid bone. Only one patient, who died due to recurrence a year after surgery, underwent complemental percutaneous radiotherapy. At present, three patients are alive and NED: one after 5 years, the others are in excellent conditions although the follow-up is still brief. According to our experience, we can affirm that in selected cases, after an accurate general evaluation of the patient (exclusion of distant metastases, preparation from a metabolic and psychological point of view) a widened forwarding total laryngectomy is a valid procedure since surgery (together with other complementary therapies), is still today the best treatment in forms with anterior evolution.

Aged↗
PubMed1994

Studies on lipid peroxidation in the rat brain.

The aim of this study was to set up a simple procedure for assessing lipid peroxidation (L.P.) and testing the activity of antioxidant compounds. L.P. was determined in rat brain homogenates by measuring the endogenous and stimulated accumulation of malonaldehyde (MDA). MDA was assayed by an HPLC method. Homogenates spontaneously formed appreciable amounts of MDA. The addition of increasing concentrations of FeCl2 resulted in a linear accumulation of MDA, up to 16.6-fold at 50 microM. An organic form of iron (Fe-saccharate) was less active on MDA formation (11.4-fold increase at 100 microM). The addition of xanthine-xanthine oxidase resulted in only a 2.4-fold increase in MDA formation. Various antioxidant or chelating compounds effectively inhibited L.P., with IC50 between 0.1 microM (phenoxazine) and 4-50 microM (alpha-tocopherol). Their potencies depended on the iron concentration and time of preincubation with the homogenates. In conclusion, this is a simple and reliable procedure for studying L.P. and inhibiting agents, provided that the experimental conditions are carefully assessed.

Allopurinol↗
PubMed1994

Chorea due to hyperthyroidism in old age. A case report.

The authors discuss the case of an elderly female patient with thyrotoxicosis and chorea. T3 and T4 serum values were high. Since the chorea disappeared with euthyroidism but reappeared whenever there was a further increase in T3 and T4, its relationship on hyperthyroidism and its reversibility are clearly demonstrated. The chorea therefore appears to be another clinical condition present in hyperthyroidism.

Aged↗
PubMed1994

Three novel types of voltage-dependent calcium channels in rat cerebellar neurons.

With the aim of characterizing the functional and pharmacological properties of the different voltage-dependent Ca2+ channels expressed in a given type of CNS neuron, we obtained single Ca2+ channel recordings from rat cerebellar granule cells in primary culture. Our data show that three novel classes of voltage-dependent Ca2+ channels are coexpressed in cerebellar granule cells. They are pharmacologically distinct from dihydropyridine-sensitive L-type and omega-conotoxin-sensitive N-type channels, and their functional properties are different from those of P- and T-type channels. The three novel 21 pS G1-, 15 pS G2-, and 20 pS G3-type Ca2+ channels have similar inactivation properties. They show complete steady-state inactivation at -40 mV and their single-channel average currents have both sustained and decaying components. They differ in activation threshold (-40 mV for G2, -30 mV for G3, and -10 mV for G1, with 90 mM Ba2+ as charge carrier), mean open time (1.2 msec for G2, 1 msec for G3, 0.8 msec for G1), and single-channel currents (at 0 mV: 0.5 pA for G2, 0.8 pA for G3, and 1.4 pA for G1). Together with the previously characterized multiple L-type Ca2+ channels (Forti and Pietrobon, 1993), G1-, G2-, and G3-type channels constitute the large majority of Ca2+ channels of cerebellar granule cells in culture. The low activation threshold of G2-type channels and their inactivation properties suggest that they might be native counterparts of the recently expressed rat brain clone rbE-II (Soong et al., 1993).

Animals↗
PubMed1993

Interferon-alpha in mixed cryoglobulinemia patients: a randomized, crossover-controlled trial.

The effects of interferon-alpha (IFN-alpha) on clinical and serologic manifestations of mixed cryoglobulinemia (MC) were investigated by randomized, crossover-controlled trial in 26 patients. The trial alternated 6 months with and 6 months without IFN-alpha therapy (2 x 10(6) IU daily for a month, then every other day for 5 months). In 22 patients, pretreatment steroid dosage remained unchanged during the study. Six patients dropped out (three because of side effects), whereas another 20 patients experienced a significant improvement of purpura (P < .02) and serum transaminases (P < .005) during IFN-alpha treatment. The presence of clinical improvement was supported by the outcome measurements of several immunologic parameters. In particular, serum cryoglobulins were significantly reduced (P < .04) during IFN-alpha therapy. A rebound phenomenon of clinical and serologic parameters was observed after IFN-alpha discontinuation. In addition, no variations were recorded during 6 months without therapy. Hepatitis C virus (HCV) RNA was detected in 91% (20/22) of our MC patients; in 2/13 cases HCV RNA was no longer detectable in serum samples after IFN-alpha therapy. Thus, IFN-alpha could be considered as treatment for MC in patients with HCV seropositivity.

Alanine Transaminase↗
PubMed1993

Occurrence and toxicity of Fusarium subglutinans from Peruvian maize.

Twenty-five samples of maize kernels collected at harvest time from geographically different corn fields in Peru, were examined for the occurrence of toxigenic Fusarium species. The most frequently recovered species were F. subglutinans (48%), F. moniliforme (46%), and F. equiseti (5%). Other Fusarium species isolated (up to 1%) included F. graminearum, F. acuminatum, F. solani, F. oxysporum, and F. culmorum. Assays of Fusarium culture extracts using Artemia salina larvae, showed F. subglutinans as one of the most toxigenic species, and its toxicity was mostly correlated to the capability to produce beauvericin (BEA). All eight tested isolates of F. subglutinans grown on autoclaved corn kernels produced BEA (from 50 to 250 mg/kg) as well as moniliformin (M) (from 70 to 270 mg/Kg). This is the first report on BEA and M production by maize isolates of F. subglutinans from South America.

Animals↗
PubMed1993

Analysis of electroporation-induced genetic damages in V79/AP4 Chinese hamster cells.

Electroporation is a recent technique used to introduce exogenous DNA into eukaryotic cells. It is important to establish that the gene of interest is transferred into a functional, non-mutated recipient cell. V79/AP4 Chinese hamster cells were exposed to high-voltage pulsed electric fields and some biological and genetic effects were measured. The results showed that cytotoxicity was related in a dose-dependent manner to the number of applied pulses. Thioguanine-resistant colony-forming cells as well as chromosomal aberrations were also induced whereas ouabain resistants and sister-chromatid exchanges were not or slightly induced. Spontaneous and electroporation-induced clones that were phenotypically TGR/HATS were used to investigate the hprt locus. Molecular screening of the locus showed that the number of deleted exons was significantly higher in induced than in spontaneous TG-resistant clones, suggesting that the genetic damages induced by electroporation concern the loss of regions well over the size of the hprt locus.

Animals↗
PubMed1993

Precursors of established hypertension in borderline hypertensives. A two-year follow-up.

We performed exercise testing, 24-h ambulatory blood pressure monitoring and echocardiography in 37 selected patients with borderline hypertension (24 men and 13 women, mean age 39.8 years, range 23-50) in an attempt to detect early cardiovascular changes that could predict future established hypertension. All subjects were clinically reinvestigated after a mean period of 28 +/- 4 months. At entry 24/37 (65%) showed an exaggerated blood pressure response to exercise (systolic pressure > or = 220 mmHg and/or diastolic pressure > or = 105 mmHg) while 13 (35%) had a normal pressure response. Patients with exaggerated pressure response showed significantly higher left ventricular mass index in comparison to those with normal pressure response (98.1 +/- 10.7 vs. 84 +/- 13, respectively; P < 0.05). They also had higher, although not significantly different, average 24-h systolic and diastolic blood pressure levels. At follow up seven subjects (16%) were diagnosed as having established hypertension, while 30 (84%) remained borderline hypertensives. No subject was judged normotensive. All of the seven hypertensive subjects were a proportion (7/24 = 29%) of the group with exaggerated blood pressure response to exercise. Also, they were the eldest of the total group of borderlines (mean age 44 years) and had the highest left ventricular mass index (100.6 +/- 13 g/m2). Borderline hypertensives show a spectrum of cardiovascular changes that could be considered as a part of the hypertensive risk profile. However, there are no specific characteristics that reliably distinguish subjects prone to develop hypertension. Repeated clinical observations and correct measurements of resting blood pressure may have greater relevance in the management of patients with borderline hypertension.

Adult↗
PubMed1993

Gene amplification and gene deletion are induced at different rates in V79/AP4 Chinese hamster cells.

The effect of mitomycin C (MMC) treatment on gene amplification and gene deletion induction in a V79/AP4 Chinese hamster cell line was investigated. Spontaneous and induced cellular variants resistant to N-phosphonacetyl-L-aspartate (PALA), which selects for carbamyl-P-synthetase, aspartate transcarbamylase and dihydroorotase (CAD) gene amplification events, and to intermediate concentrations of 2,6-diaminopurine (DAP), which selects for adenine phosphoribosyl transferase (aprt) gene deletion events, were isolated. The molecular analysis of spontaneous and induced PALA- and DAP-resistant clones showed that while in the former the CAD gene was amplified, in the latter both mutations and deletions occurred at the aprt gene. These results indicate that MMC favored the rise of gene amplification rather than gene deletion events, and suggest that aberrant DNA replication processes were responsible for the observed gene amplification.

2-Aminopurine↗
PubMed1993

[Multiple primary malignant tumors of the larynx and lung].

The association of laryngeal and pulmonary neoplasms is one of the most frequent among multiple primary malignant tumors and represents an important problem in terms of prevention and diagnosis. The present study involves 22 cases of associated tumors observed from January 1st 1977 and December 31st 1992. All the patients involved were male, average age 62 years, who had been treated for laryngeal cancers, mostly laryngeal epidermoid carcinoma. Pulmonary cancers (simultaneous, synchronous, metachronous) were diagnosed in all these subjects and one patient presented 2 autonomous bronchial lesions which arose in different periods. Five patients out of 22 (23%) are still alive and with no evidence of disease (NED), 2 more patients are alive although not disease-free. After reporting some considerations regarding the neoplastic association involving the larynx and the lung as well as the increased risk of pulmonary neoplasm in those patients treated for supraglottic lesions, the authors emphasize the importance of personal and family history for cancer and suggest a classification of the risk to develop a second malignancy in these patients.

Adenocarcinoma↗
PubMed1993

[Parotid metastases of malignant tumors of the head].

Tumors of the head as well as other distant tumors may metastasize to the lymph nodes of the parotid gland. Metastases from head malignancies are much more frequent than those arising in distant organs. The authors report their experience in three cases of parotid lymph nodal metastases from head neoplasms: nasal septum carcinoma, left external auditory canal carcinoma and right suborbital skin melanoma. In two cases nodal metastases appeared after the treatment of the primary malignant tumor; in one case metastases were simultaneous to it. All patients were treated surgically (total parotidectomy with facial nerve preservation) and in two cases a submaxillary and functional neck dissection was carried out. Only one patient is alive and disease-free at three years from operation. The authors believe that total parotidectomy performed for nodal metastases involving the parotid gland is to be considered a true "parotid dissection", either "curative" or "prophylactic", depending on whether it is carried out when lymph nodes are palpable or not.

Aged↗
PubMed1993

[An algorithm for the analysis of the circadian profile of the arterial pressure in normotensive subjects].

In this paper we proposed the use of a spectral analysis technique, the fast Fourier transform (FFT), for the evaluation of the normal circadian blood pressure rhythm. By means of this algorithm it is possible to separate the slower and reproducible variations of the blood pressure profile (probably due to endogenous rhythm) from the faster and random ones (due to psychophysical status of the subject). The FFT technique is used for the analysis of ambulatory blood pressure monitorings obtained in 66 normotensive subjects (38 males and 28 females, mean age 35 +/- 10 years). Taking into account the mean duration of pressure variations related to major daily activities (e.g. sleeping, eating, etc) it is proposed to consider the first 10 harmonics as those having the main influence on the circadian blood pressure rhythm. The amplitude of the first 10 harmonics of the whole sample was evaluated by using the chi 2 and the Kolmogorov tests, and the results confirmed the assumption of a normal distribution of the amplitudes. The 95% confidence interval of these harmonics was chosen as the criteria for defining a normal range for the circadian blood pressure rhythm. This approach was tested in a group of 4 hypertensive patients showing that alteration of the circadian blood pressure rhythm can be easily diagnosed.

Adolescent↗
PubMed1992

Comparison of anti-hepatitis C virus detection with ELISA assay and RIBA 4 in dialysis patients: our experience.

Hepatitis C virus (HCV) has been demonstrated to be the main cause of non-A, non-B hepatitis and the emergent infectious illness in dialysis units. At present, the anti-HCV 100 ELISA and an immunoblot assay in which 2 new antigens are included, are available. We have tested 110 patients on chronic dialysis with anti-C100 ELISA. Twenty-seven of them were anti-HCV positive. We tested the 27 anti-HCV-positive and 7 anti-HCV-negative patients with the RIBA 4 assay. The results were similar with both test.

Enzyme-Linked Immunosorbent Assay↗
PubMed1992

Radiation therapy maintenance. A successful in-house program.

With the development of complex equipment technologies in the medical care industry and particularly in radiation therapy, the costs required to keep equipment in proper operating condition are substantial. An "in-house" radiation therapy maintenance program can provide significant savings in equipment maintenance costs as compared to the cost of maintenance contracts. Additionally, the skills of the personnel providing this maintenance program can be used for ancillary areas of the therapy department.

Costs and Cost Analysis↗
PubMed1991

Antibodies to hepatitis C virus in patients with mixed cryoglobulinemia.

The prevalence of antibodies to hepatitis C virus (HCVAb) was investigated in 52 unselected patients with mixed cryoglobulinemia and in 84 patients with other systemic immunologic diseases. HCVAb were detected by an enzyme-linked immunosorbent assay, and their specificity was evaluated by a recombinant-based immunoblot assay. The presence of HBV-related markers was investigated in the same samples. HCVAb were found in 54% of mixed cryoglobulinemia patients, and the finding was confirmed by recombinant-based immunoblot assay in all cases. HCVAb and/or HBV markers were present in 70% of the patients. HCVAb seropositivity was significantly more frequent in mixed cryoglobulinemia patients with biopsy-proven liver involvement (P less than 0.01) and with increased serum transaminase levels (P less than 0.01). HCVAb were virtually absent in control patients with other immunologic diseases. These results support the notion that viral agents, i.e., HCV and possibly HBV, have a role in the pathogenesis of mixed cryoglobulinemia patients.

Adult↗
PubMed1991

[Thyroid gland and carcinoma of the hypopharyngeal-laryngeal region].

The thyroid gland harbours many diseases which require a surgical treatment; the gland may also be involved by some secondary malignant neoplasms. Such type of involvement by laryngeal and hypopharyngeal cancers is more often due to direct extension rather than metastases. In this paper the Authors report their experience of tumoral involvement of the thyroid gland in 35 patients with laryngeal or hypopharyngeal cancer observed from 1986 to 1990. All patients had an epidermoid carcinoma of the larynx or hypopharynx that required an hemithyroidectomy (always plus isthmectomy) or an isthmectomy associated to laryngectomy. On pathologic examination 5 thyroid specimens revealed tumoral involvement in patients with laryngeal neoplasms: 1 case of solitary metastasis and 4 cases of direct extension. In patients with hypopharyngeal lesions, on the contrary, the gland was, in all cases, undamaged. For this very interesting and uncommon finding the Authors agree with Harrison's proposal suggesting total thyroidectomy is necessary in case of subglottic lesions while in all the other laryngeal and hypopharyngeal lesions the homolateral lobe of the thyroid gland and the isthmus should be removed with the specimen also performing a frozen section examination of the contralateral lobe. In this study tumoral involvement of the thyroid gland appeared to be a very important negative prognostic factor and was higher in the subglottic and anterior commissure lesions.

Aged↗