Biomedical subjects

A Volpe

Publications and source records attributed to A Volpe.

At least 181 records · Page 10Linked to original sources

PubMed1993

[The role of tomography (X-ray and magnetic resonance) in the diagnosis and determination of the extension of tumors in the roof of the third ventricle].

We describe the CT scan and MR appearance of neoplastic lesions affecting the roof of the third ventricle. The neoplastic lesions of this region may be of neuroepithelial origin (sub-ependymoma, colloid cyst), meningeal cell origin (meningiomas), metastatic or primary localization of lymphoproliferative tumors (lymphomas) and dysembryogenetic origin (epidermoid tumor). CT scan and MR imaging are useful techniques for diagnosis and planning of surgical or medical treatment. The primary role of these imaging techniques, is discussed in the quantification of extension, biologic malignancy and anatomical relationships between pathologic lesion and normal nervous tissue.

Cerebral Ventricle Neoplasms↗

PubMed1993

[Role of magnetic resonance in the evaluation of testicular diseases].

The above paper was intended to evaluate the usefulness of MRI in the study of pathologies involving the testis, on the basis of the authors' experience and of the relevant literature. Pathologies considered included cryptorchidism, torsion of the spermatic cord, epididymitis, orchitis, and testicular tumors. MRI proved very useful in cryptorchidism, thanks to the multiple planes and good contrast resolution between different tissues. It also yields valuable information allowing to distinguish between malignant transformation of the retained testicle and its fibrotic involution. In malignant pathologies, MRI is useful for differential diagnosis between seminomatous and non-seminomatous tissues, while for purposes of staging its accuracy is only 36% but is nevertheless superior to that of U.S. (45%). In the case of other pathologies, MRI findings are non specific, and the technique should therefore be employed only when U.S. findings are unsatisfactory.

Diagnosis, Differential↗

PubMed1993

[Current role of computerized tomography and prospectives of the use of magnetic resonance in the diagnosis of aortic abdominal aneurysms and evaluation of their complications].

In this work we discussed the role of conventional radiology, ultrasonography (US), angiographic study, CT scan and MR imaging in the diagnosis of abdominal aortic aneurysms and their complications. US is the most suitable technique for screening and follow-up study of aortic aneurysms. Unfortunately it is not so reliable in the study of visceral arteries and in fat patients. Aortic angiography is the most useful method for the study of visceral arterial branches, but it does not show the phlogistic changes as well as the peripheral thrombotic alterations within the lesion. TC scan is also a useful technique in the study of aortic aneurysm, although it is not so accurate in detecting the visceral arterial branches. Finally, we think that MR imaging is the most reliable method for the diagnosis of aortic aneurysm. Movement artifact and lack of information due to the poor visualization of calcifications are still the principal limits of this technique.

Aortic Aneurysm, Abdominal↗

PubMed1993

[Diagnostic imaging in the evaluation of masses developing in the cerebral ventricles].

CT scan and MR imaging of intraventricular masses are discussed in this work. The lesions affecting this region may be of neoplastic, vascular or phlogistic origin. CT scan and MR imaging are useful for diagnosis and management of these lesions. Intraventricular masses are well documented by high resolution CT scan after administration of endo-rachideal metrizamide, during ventriculographic studies. This technique gives important informations about peripheral relationship of intraventricular masses with increased liquoral fluid. MR imaging is also available for characterizing pathologic tissues, and for detecting the anatomic relationships between pathologic and normal structures.

Astrocytoma↗

PubMed1993

[Comparison of magnetic resonance and other imaging methods in the diagnosis of diseases of the seminal vesicles].

The aim of this work was to evaluate the usefulness of MR imaging in the diagnostic study of seminal vesicles and to emphasize the relationships between this technique, CT scan and trans-rectal ultrasonography (TR-US). We discussed pathological findings due to congenital anomalies, phlogistic or neoplastic lesions and iatrogenic changes of normal tissues. MR imaging and TR-US seem to be the most reliable techniques for typing pathological tissues and for grading the extension of neoplatic masses arising from bladder, prostate, and rectum, involving seminal vesicles.

Diagnostic Imaging↗

PubMed1993

[Aortic dissection: the role of diagnostic imaging, with special reference to magnetic resonance imaging and its implications in the pathogenesis].

The aim of this work was to evaluate the usefulness of angiography, CT scan and MR imaging in the diagnosis of aortic dissection, on the basis of the authors' experience and literature review. Angiographic study is still considered the first choice technique in the diagnosis of aortic dissection, although it is considered not completely safe. CT scan allows to note the early thickening of the vessel walls (due to intraparietal bleeding) and the presence of calcifications in the thrombosed portion of the lesion. MR study allows multiplanar study of the lesions without contrast medium, and best visualization of subendothelial bleeding in dissections without intimal lesion.

Aortic Dissection↗

PubMed1993

Isolation and identification of rotaviruses as aetiological agents of neonatal diarrhoea in kids. Electrophoretical characterization by PAGE.

Six strains of cytopathogenic enteric virus for the continuous cell line MA-104 were isolated from samples of the diarrhoeic stools of kids (Capra hyrcus) with acute enteritis. The samples were obtained from two stock farms (RM and SI) in central Italy. Four viruses from the RM stock were identified as rotaviruses of the antigenic group A by the Elisa test performed with SA-11 antirotavirus monoclonal antibodies and the direct immunofluorescence test with IgG bovine antirotavirus. Electrophoretical analysis of the viral dsRNA in these strains showed a pattern of eleven bands arranged in the typical "long pattern" of rotavirus group A. Two electrophoretical variants were identified in two separate cases of neonatal diarrhoea in the RM stock over a period of one year. The other two strains, one isolated in the RM stock and the other in the SI stock, gave negative results in serological tests for antigenic group A rotavirus and showed a double chain RNA consisting of 9-10 segments, unrelated to rotavirus or pararotavirus.

Animals↗

PubMed1992

Long-term immunogenicity safety and efficacy of a recombinant hepatitis B vaccine in healthy adults.

Two hundred healthy adults seronegative for HBV markers received three 10 or 20 mcg injections of a vaccine formulated from HBsAg produced by a recombinant strain of the yeast Saccharomyces cerevisiae. The vaccine was administered intramuscularly at 0, 1, and 6 months in the deltoid region. The seroconversion rates, expressed in GMT/IU/1 were determined at 1, 2, 6, 7, 12, 24, 36 and 48 months following the initial injection. No severe or serious adverse reactions attributable to the HB vaccines were observed in any subject. The seroconversion rates following the 20 mcg dose of recombinant vaccine were always higher than those observed after the 10 mcg dose, but the differences were not statistically significant. Also the GMT values were lower after the 10 mcg dose of vaccine. Females showed a higher anti-HBs response than males; an age-dependent effect was observed in the anti-HBs response as regards both the percentage of responders and the antibody concentrations in the serum. No adverse reactions to the vaccine were observed. The rDNA vaccine did not induce a response to yeast-derived impurities and did not increase anti-yeast IgE antibody titres. The results of this study have shown that the Amgen rDNA vaccine is safe and clinically well tolerated, and that it provides protection against infection and disease. A vaccination dose of 20 mcg appears more advantageous for healthy adult subjects.

Adolescent↗

PubMed1992

Efficacy of hormone replacement therapy in postmenopausal women with oral discomfort.

The increase in incidence of oral discomfort among women in a menopause is probably due to hormone modifications. This study evaluated the efficacy of hormone replacement therapy in 27 postmenopausal patients, aged 48 to 58 years, with oral discomfort and no local irritants and in 47 postmenopausal women with no oral discomfort. Patients were treated with conjugated estrogens for 21 days and medroxyprogesterone acetate from day 12 through day 21. Hormone-replacement therapy had no effect on oral cytology in the 40 symptom-free postmenopausal women compared with a group of 47 postmenopausal women who had no oral symptoms and were not treated. Hormone-replacement therapy relieved symptoms and improved oral cytohormonal features in 15 of 27 patients with symptoms. Nuclear estrogen receptors were found by immunohistochemical assay in 8 of 10 randomly selected patients with symptoms who responded to hormone-replacement therapy, but not in 2 patients who did not benefit from hormone-replacement therapy. Estrogen receptors were also found in 6 of 10 fertile women with no oral disease. Our results suggest that oral discomfort may be related to steroid hormone withdrawal only in some postmenopausal women and that replacement therapy may improve the clinical picture and cytologic features in this group of patients. Immunohistochemical identification of estrogen receptors may help to identify patients for whom hormone-replacement therapy may be beneficial.

Burning Mouth Syndrome↗

PubMed1992

Studies on direct intraperitoneal insemination in the management of male factor, cervical factor, unexplained and immunological infertility.

One-hundred-and-twenty couples with male factor, cervical factor, unexplained or immunological infertility underwent direct intraperitoneal insemination (DIPI) of capacitated spermatozoa, combined with ovarian stimulation for a total of 254 cycles. Pregnancy occurred in 47 cycles, resulting in an overall pregnancy rate of 40.5% per patient (two pregnancies occurred in two patients) and a cycle fecundity of 18.5%. Of the patients, 23 have delivered live infants (one twins, 22 singletons), 15 (32%) miscarried and 9 have ongoing pregnancies. The cycle fecundity rates increased with increasing sperm concentration and total progressive motile count, both before and after sperm preparation (r = 0.8161, r = 0.8717 and r = 0.759, r = 0.795, respectively). However, there were two pregnancies where the inseminates had a count of 0.1 x 10(6) total motile spermatozoa. DIPI as an outpatient, in-vivo conception procedure offers encouraging results and is recommended before attempting more costly and invasive assisted reproduction techniques.

Female↗

PubMed1992

Effects of growth hormone administration in addition to gonadotrophins in normally ovulating women and polycystic ovary syndrome (PCO) patients.

Follicular fluid sex-steroids, insulin-like growth factor-I (IGF-I), IGF-I binding protein (IGF-I-BP) and epidermal growth factor were investigated in patients with polycystic ovaries and normally ovulating women, following ovulation induction with gonadotrophins or growth hormone plus gonadotrophins. Growth hormone supplementation enhanced the ovarian response to gonadotrophins, and significantly increased follicular fluid IGF-I in both groups, without affecting follicular fluid epidermal growth factor; growth hormone supplementation significantly decreased follicular fluid androstenedione in both groups.

Adult↗

PubMed1992

Hepatitis C virus in hemodialysis patients.

Anti-HCV prevalence in 284 hemodialysis patients was assessed using the Abbott HCV-EIA test. Anti-HCV positivity was found in 19.4% of patients, was higher in males than in females and progressively increased with age. A correlation between time of dialysis treatment, transfusions and ALT course was found. These data suggest that HCV infection is a very important risk in dialysis units.

Adolescent↗

PubMed1992

Immunogenicity and efficacy of anti-hepatitis B vaccines in hemodialysis patients.

The 7-year follow-up with plasma-derived and 2-year follow-up with r-DNA vaccines have indicated the safety, immunogenicity and persistence of a vaccine-induced antibody response in hemodialysis patients. The results of our study indicate that these subjects have a lower and often inadequate immunogenic response to the HB vaccine and that the r-DNA vaccine gives a better seroconversion rate than the plasma-derived vaccines.

Hepatitis B↗

PubMed1992

[A comparison between intraurethral echography, computed tomography and magnetic resonance in the staging of bladder tumors].

The purpose of our study was to assess the utility of CT and MRI in the staging of bladder carcinoma. The overall accuracy of MR is in the range of 66 to 85%. T2 weighted and post-Gadolinium T1 weighted images allow one to differentiate T1-T2 from T3a type of neoplasms. Perivesical fat invasion is well shown with T1w images while pelvic wall invasion is better seen on T2w--images. The overall accuracy of CT ranges from 64 to 92%. CT cannot distinguish stage T1 from stage T3a tumors CT is accurate for demonstrating perivesical fat invasion. In the assessment of lymph node metastases CT and MRI have low sensitivity but high accuracy. Trans-urethral sonography is more accurate than CT and MRI in the staging of parietal invasion and it permits the differentiation between T1, T2 and T3a stages even though the distinction between T2 and T3a type of tumors is not always possible. Trans-urethral sonography is not useful in assessing extravesical extension and lymph node metastases. In summary, trans-urethral sonography is the method of choice for evaluating parietal invasion. CT and MR are very accurate for evaluating perivesical fat invasion and are also quite accurate for evaluating lymph nodes. MRI is superior to CT in distinguishing tumors limited to superficial muscle from those that invade deep muscle. MRI can also be helpful in distinguishing the tumor from fibrosis and edema.

Diagnosis, Differential↗

PubMed1992

[Computed tomography and magnetic resonance in the TNM staging of pulmonary carcinoma].

On the basis of a review of the literature and of the authors' personal experience, the usefulness was evaluated of CT and MR for the staging of lung carcinoma. Neither method was found to be useful for diagnosis; as to staging, neither is capable to distinguish between simple adhesion and infiltration of adjacent structures by the tumor. As compared to CT, MR has the advantage of showing many layers and better contrast resolution but spatial resolution is poorer. MR was superior to CT for the study of hilar lesions (easily differentiated from vessels) and for those involving the upper pulmonary sulcus. The accuracy of evaluation of the N parameter was the same for both methods whereas for the M parameter RM was more accurate than CT. Considering the wide margins for technological improvement of MR, a more important role for this method compared to CT can be hypothesized.

Carcinoma↗

PubMed1992

Prevalence and incidence of hepatitis C virus (HCV) in hemodialysis patients: study of risk factors.

The prevalence of antibodies against hepatitis C virus (HCV) was assessed in 246 hemodialysis patients who attended a dialysis unit in Bari, using a recombinant enzyme immunoassay test (Abbot Lab.). Fifty-six (22.8%) sera were reactive to anti-HCV. The reactivity was confirmed in 46 specimens (18.7%) using the Abbott EIA HCV neutralization test. The anti-HCV prevalence was higher in males than in females and increased with age, duration of dialysis and number of transfusions. Moreover, a correlation between the presence of anti-HCV and the persistent increase of ALT was noted. The HCV-infection attack rate was calculated using the frozen sera collected from 1984 to 1990: the incidence of infection in the first year was 6.1%, and in following years 4.6%, 4.9%, 3.1%, 2.1% and 2.2%, respectively.

Adult↗

PubMed1992

Sperm retrieval for direct intraperitoneal insemination in a diabetic with retrograde ejaculation. A case report.

Retrograde ejaculation is an uncommon form of male infertility. It may occur in diabetics from neuropathy involving the sympathetic fibers innervating the bladder neck. Treatment of infertility in these cases is with artificial homologous insemination. Several techniques for semen recovery from the bladder have been proposed. This paper describes a case of twin pregnancy following direct intraperitoneal insemination (DIPI) of semen retrieved from a diabetic man with retrograde ejaculation. Retrieval of semen was performed in this case by spontaneous voiding of urine after the introduction of a suitable medium into the bladder and before ejaculation. The quality of the semen was examined after spontaneous urination before DIPI. The poor quality of the spermatozoa induced us to introduce into the bladder a suitable medium before ejaculation and sperm recovery.

Administration, Intravesical↗

PubMed1991

Follicular fluid steroid and epidermal growth factor content, and in vitro estrogen release by granulosa-luteal cells from patients with polycystic ovaries in an IVF/ET program.

The follicular fluid (FF) content of androgens, estrogens and epidermal growth factor (EGF) has been evaluated in a group of patients with policystic ovary disease (PCO) and in one of normally-ovulating infertile women (NOW) in an IVF/ET program. The in vitro response to follicle-stimulating hormone (FSH) has been also evaluated in granulosa luteal cells from the same patients. PCO patients showed significantly higher FF androstenedione (delta 4) and testosterone (T) and similar FF estrone (E1) and 17 beta-estradiol (E2) levels compared to controls. In vitro production of E1 and E2 by granulosa luteal cells from PCO patients and from controls were overlapping and their response to FSH was similar. These data indicate a normal intrinsic potential aromatase activity in ovaries from PCO patients stimulated with gonadotropins and suggest that PCOs do not derive from inherent ovarian aromatase deficiency. Increased FF androgen content following gonadotropin stimulation may result from theca cell hyperactivity and androgen accumulation in the follicular antrum of rescued hyperandrogenic follicles as well as from inhibitory factors that may inhibit aromatase activation in vivo, partially counteracting the effect of gonadotropins. FF EGF levels were significantly higher in the group of PCO patients compared to those of NOW. EGF may play a role in blunting the in vivo response of granulosa cells to gonadotropins.

Androstenedione↗