Biomedical subjects

D Fontana

Publications and source records attributed to D Fontana.

At least 55 records · Page 3Linked to original sources

PubMed1997

Pamidronate administration improves the secondary hyperparathyroidism due to "Bone Hunger Syndrome" in a patient with osteoblastic metastases from prostate cancer.

BACKGROUND: The so-called Bone Hunger Syndrome is a metabolic derangement that sometimes complicates the natural history of prostate cancer patients with osteoblastic bone metastases. An excessive bone formation leads to calcium entrapment in bone and the subsequent increase of parathyroid hormone (PTH) levels, in response to calcium demand. PTH elevation stimulates the osteoclasts in sites distant from those involving the tumor, leading to osteomalacia. METHODS: PTH and markers of bone turnover were monitored every 3 weeks, from the start of pamidronate treatment in a prostate cancer patient with progressive disease, to luteinizing hormone releasing hormone analog (LHRH-A) administration, developing hyperparathyroidism, hypophosphatemia, and albumin corrected serum calcium close to the lower limit of normality. Serum bone alkaline phosphatase (BALP), assessed by two different methods: electrophoretic and immunoradiometric, and urinary levels of markers of bone collagen breakdown were also remarkably elevated. RESULTS: As a consequence of pamidronate infusion (60 mg e.v. every 3 weeks for a total of four times), BALP and PTH decreased consistently, serum calcium and phosphorus returned within the normal range, while markers of collagen resorption showed a significant decrease at the 9th week, preceded by a transient rise. CONCLUSIONS: This case report indicates that bisphosphonates could inhibit both osteoclast activity. The anti-osteoblastic effect is mainly responsible for the improvement of the pretreatment calcium imbalance of our patient towards hypocalcemia and the consequent hyperparathyroidism.

Aged↗

PubMed1997

Insulin modulation of an endothelial nitric oxide component present in the alpha2- and beta-adrenergic responses in human forearm.

We explored in 51 normal subjects, distributed in various series of experiments, whether endothelium nitric oxide may play a role in insulin modulation of alpha2- and beta-adrenergic- evoked vascular responses. In particular, we examined the forearm blood flow response (FBF, ml.min-1.dl-1) to intrabrachial infusion of BHT-933 (0.5, 1, and 2 microg.min-1.dl-1) or isoproterenol (1, 3, and 6 ng. min-1.dl-1) in control conditions, during intrabrachial infusion of insulin alone (0.05 mU.kg-1.min-1) and associated with l-N-monomethylarginine (L-NMMA) (0.05 microg.min-1.dl-1), a nitric oxide synthase inhibitor. In control conditions both BHT-933 and isoproterenol induced a dose-dependent vascular response. Local hyperinsulinemia (deep venous plasma insulin 68.5+/-4 microU/ml) did not change basal FBF whereas attenuated BHT-933 vasoconstriction and enhanced isoproterenol vasodilation. L-NMMA reduced basal FBF and abolished the insulin effect on BHT-933 and isoproterenol response. To clarify whether a nitric oxide component is included in alpha2- and beta-adrenergic response and may be responsible for insulin vascular effect, we further examined BHT-933 and isoproterenol responses during nitric oxide inhibition. Interestingly, L-NMMA potentiated the BHT-933 vasoconstriction and attenuated the isoproterenol vasodilation and, in these conditions, insulin was no more able to exhibit its vascular effects. Finally, to rule out the possibility that the conteracting effect of L-NMMA may not be specifically related to insulin action, dose-response curves to phenylephrine (0.5, 1, and 2 microg.min-1.dl-1) or sodium nitroprusside (1, 2, and 4 microg.min-1.dl-1) were also performed. Both insulin and L-NMMA were unable to alter the phenylephrine-induced vasoconstriction and the sodium nitroprusside vasodilation. In conclusion, our data demonstrate an endothelial nitric oxide component in the alpha2- and beta-adrenergic vascular responses which is the target of the insulin vascular action.

Adrenergic alpha-Agonists↗

PubMed1997

Alterations in striatal dopamine overflow during rotational behavior induced by amphetamine, phencyclidine, and MK-801.

Rats lesioned unilaterally in the medial forebrain bundle with 6-OHDA rotated ipsilateral to the lesion following injections of amphetamine, phencyclidine (PCP), and MK-801. Concurrent measurement of striatal dopamine (DA) in the intact striatum with in vivo microdialysis revealed a dissociation between rotational behavior and alterations in DA overflow induced by the three drugs. Amphetamine produced robust ipsilateral rotational behavior and a substantial elevation in striatal DA (approximately 130% increase at asymptote). PCP produced comparable increases in rotational behavior, but only approximately 30% increase in striatal DA. MK-801 also had a comparable behavioral effect but failed to alter DA overflow in the intact striatum. Since MK-801, a noncompetitive NMDA antagonist which does not enhance extracellular dopamine in the striatum, is able to produce ipsilateral rotational behavior in rats with unilateral nigrostriatal lesions, it is likely that the effects of PCP may also be determined predominantly through NMDA blockade in this model.

Amphetamine↗

PubMed1997

Rapid identification of Mycobacterium tuberculosis complex on urine samples by Gen-Probe amplification test.

The aim of the study was to evaluate the applicability to urine samples of the Amplified Mycobacterium tuberculosis Direct Detection Test (AMTD), which is currently used to identify this organism in respiratory specimens within a few hours. The study was performed on 95 patients, comprising 35 subjects with a high index of suspicion for active tuberculosis of the urinary tract and 60 subjects with evidence of non-mycobacterial disease. One urine specimen from each subject was examined by microscopy, culture and AMTD. AMTD was positive in 38 specimens and negative in 57. Assuming culture as the reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 91.93%, 86.84% and 100%, respectively. Reassessing the discrepancies between AMTD and culture by review of patients' charts, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 93.44%, 89.47% and 100%. The results of the study as well as the characteristics of AMTD encourage its use for the rapid recognition of urinary tract tuberculosis, although its findings should be interpreted cautiously when the clinical picture is not consistent with an active tuberculosis.

Adult↗

PubMed1997

Molecular biology in uro-oncology: clinical application. Prognostic factors in bladder cancer.

In the bladder cancer the most important prognostic factors are the stage, the grade, the presence or absence of lymph nodal metastasis, the response to therapy with B. C. G. etc.... In any case, even in the context of the same clinical stage, it is not possible to correctly evaluate the evolution of the disease. The Author did a literature revision and got a personal contribution about the effective utility of same biological prognostic factors. In a study about superficial bladder tumor using monoclonal antibody MIB-1 (Ki-67) a correlation between proliferation index (P.I.) and grade was noted. In particular the presence of a P.I. above 40% correlated with greater precocity and frequency of recurrences. A similar study showed that the expression of protein p21 correlated with a greater precociousness and with recurrence frequency. In conclusion, we have also carried out an evaluative study on the expression of oncosuppressor gene p53. In superficial bladder cancer this study showed up a correlation between the expression of protein p53 and a greater precociousness and frequency of recurrences.

Biomarkers, Tumor↗

PubMed1996

Changes in control beliefs in Portuguese primary school pupils as a consequence of the employment of self-assessment strategies.

Previous findings suggest that a move towards internality in control beliefs is positively associated with academic success. The present study set out to explore the extent to which the use of self-assessment techniques by Portuguese primary school children is positively associated with increased internality, and to establish whether the presence of these techniques together with enhanced internality correlate with improved academic (mathematical) performance. A sample of Portuguese primary school teachers was coached in how to teach self-assessment techniques to their children, and these children were then monitored by the researchers over an eight-month period. Results on the Control, Agency and Means-End Interview Questionnaire (Skinner, Chapman & Baltes, 1988a, 1988b) indicated that at the end of the experimental period the children showed significantly less dependence upon external sources of control (perceived externality), and upon luck and unknown control as explanations for school academic events when compared to a matched control group of children who were not using pupil self-assessment. In addition, the children regularly using self-assessment strategies significantly increased their relative internality over the period concerned, and showed significant improvements in academic performance (as measured by mathematics scores) relative to the control group.

Achievement↗

PubMed1996

Evaluation of c-ras oncogene product (p21) in superficial bladder cancer.

OBJECTIVES: The aim of our study is the evaluation of the prognostic importance of p21 protein in superficial bladder cancer. METHODS: One hundred and fourteen patients with an initial diagnosis of monofocal bladder cancer (stage Ta-T1) following TUR were investigated. On the tissue removed by TUR, besides the usual pathological evaluation, an immuno-histochemical investigation was carried out in order to ascertain the presence of c-ras oncogene product (protein p21). The actuarial curves concerning the time free from the first recurrence were computed, comparing different subgroups in regard to protein p21 presence, grade and stage of the tumour. RESULTS: The analysis of the results shows the importance of tumour stage as a predictor of recurrence, as well as that of the presence of c-ras products. This last factor increases the risk of recurrence almost 2-fold, in the same time lag, for c-ras-positive patients (p < 0.001). The prognostic significance of c-ras is independent of stage. CONCLUSION: Our data underline the possibility of acquiring important information on the prognosis of superficial bladder cancer patients, pointing out the significance of c-ras oncogene product.

Actuarial Analysis↗

PubMed1996

[An unusual association: Jaffe-Linchtenstein syndrome, arcuate ligament syndrome and hepatic adenoma].

A case of a woman affected by an unusual association of rare diseases, is presented. The patient was referred to our department for acute anaemia. Preoperative investigations revealed that the patient was affected by fibrous polyostotic dysplasia, so called Jaffè-Lichtenstein syndrome. The presence of skin brown spot and endocrine disorders requiring pill administration, allows to classify the patient as carrier of Albright syndrome. Moreover, the angiography pointed out a celiac trunc stenosis (Dunbar syndrome). The long-standing administration of the pill could be the cause of bleeding adenoma. The patient underwent hepatic resection. We did not treat the Dunbar syndrome because of poor symptoms. From literature, we review some opinions on the fibrous dysplasia of the bone.

Adenoma↗

PubMed1996

[Usefulness of transvaginal echography in the study of organic pathology of the female urethra].

The Authors describe their experience about the use of vaginal ultrasound in the diagnosis of some organic disease of the female urethra. The ultrasonography was performed with the 5 Mhz endocavitary probe and patients in lithotomy position and filled bladder. With this method has been possible value the urethral and peri-urethral echostructure and urethral calibre during micturition. the Authors visualized 20 urethral diverticula, 6 stenosis, 2 carcinomas and 1 leiomyoma. They show the great reliability of this investigation and argue that it may be present as a first instrumental approach in the clinical suspicion of an organic pathology of the female urethra.

Female↗

PubMed1996

[Transvaginal echography in the study of urinary stress incontinence].

Hypermobility of the bladder neck in response to increased intraabdominal pressure is one cause of stress urinary incontinence in women. Vaginal ultrasound (u.s.) is reliable and minimally invasive method for demonstrating bladder neck hypermobility. The Authors studied 50 women with S.U.I. and 40 with no history of S.U.I. measuring the distance from the bladder neck to the midline of the symphysis pubis (P.V.) and the angle between the BP line and the midline of the symphysis pubis (A.I.U.). The continent women were characterized by a median A.I.U. of 70 degrees and mean B.P. of 25.6 mm, at rest, a median A.I.U. of 80 degrees and a mean B.P. of 20 mm. at stress. The incontinent women were characterized by a median A.I.U. of 80 degrees and mean P.V. of 22.5 mm. at rest, and a median A.I.U. of 95 degrees and mean P.V. of 10 mm. at stress. There is a significant difference between the two groups. The Authors recommend the vaginal u.s. as reliable, practical, economical and patient accepted method to study the bladder neck mobility.

Female↗

PubMed1996

[Treatment of a solitary renal cyst using percutaneous drainage and repeat alcoholization].

The Authors report their results on the treatment of simple voluminous renal cyst with percutaneous drainage and three times repeated sclerosis with pure alcohol every 24 hours. After a mean follow-up of 28 months They report a 96% of success with only two recurrences. Since the fair results and low invasiveness of the method, the Authors propose the repeated alcoholization in the treatment of simple voluminous renal cysts.

Combined Modality Therapy↗

PubMed1996

[Echographic aspects of renal tuberculosis].

In this study the Authors examine the utility of the ultrasonographic investigation in the preoperative evaluation of 22 patients submitted to nephrectomy for tubercular lesions, comparing the informations obtained from this procedure with the histologic report. The renal ultrasonography execute with a Toshiba 3.5 Mhz probe, has been utilized to value morphology, volume, parenchymal echostructure and hydronephrosis. According to the Author's series, the ultrasonography has shown a 100% sensitivity permitting to well value the presence of parenchymal lesions and hydronephrosis. As regards the tubercular renal injuries the ultrasonography is non-specific because it does not allow to have pathognomonic images. The results obtained from the U.S. are overlapping to the Results Related from the literature for abdominal CT. The Authors argue that U.S., rapid and economical investigation is an efficient complement to the urography for an exhaustive preoperative evaluation of patients suffering from renal Tuberculosis.

Humans↗

PubMed1995

[Psychosexual interventions combined with biologic therapy of erectile dysfunction].

The authors, beginning from che concept of erectile disorder with mixed pathogenesis, describe its clinical dimension. The psychic variables which prevent the use of biologic-andrologic therapy (FIC, penis prosthesis) are then considered: 1) psycho-sexual difficulties before the onset of the organic lesion; 2) the partner's relationship with the biologic-andrologic therapy; 3) the patients' relationship with the biologic therapy. A model of intervention (Group Psycho-sexologic Intervention) on the psychic variables interfering with the use of the biologic-andrologic therapy is then described. The authors end by considering the psychological impact and the possible psychoiatrogenicity of biologic-andrologic therapies.

Erectile Dysfunction↗

PubMed1995

[Italian centers that deliver treatment for male sexual dysfunction].

In agree with President and Committee of Andrological Italian Society (S.I.A.), authors have carried on a research to know: 1) main features of Italian Structures interested in male sexual dysfunction 2) actual trend in diagnosis and therapies of male sexual dysfunction, Authors report results and data about this research, particularly regarding new trends in therapia (therapy).

Delivery of Health Care↗

PubMed1995

[Penile prosthesis].

In this article the Authors, after describing the history of the penile prosthesis surgery and analyzing the technical progresses made in the last twenty years, offer their personal experience and data from the most recent literature about treatment of erectile dysfunction through the application af penile prosthesis, about the indications for the operation and the choice of the type of prosthesis. They also explain all the possible complications and eventual mechanical failures, which have considerably decreased in the last few years.

Erectile Dysfunction↗

PubMed1994

Mechanisms of rapid bone loss following cardiac transplantation.

Rapid bone loss after orthoptic cardiac transplantation (OHTX) is a major problem; however, the mechanisms are poorly understood. To investigate these mechanisms we measured biochemical and hormonal indices of bone turnover serially in 25 patients (21 men, 4 women) after OHTX. Serum osteocalcin was reduced immediately post-OHTX (2.2 +/- 0.5 ng/ml) but rose significantly by 6 and 12 months (14.1 +/- 2.5 and 15.7 +/- 2.2 respectively). Bone resorption indices (urinary hydroxyproline/creatinine and calcium/creatinine ratios) were increased immediately post-OHTX but fell by 6 months. Serum testosterone was reduced in males but recovered towards normal values by 6-12 months. Regression analysis showed lumbar bone loss was predicted independently by the change in both serum osteocalcin and testosterone. The data suggest that bone loss post-OHTX is due to a combination of accelerated turnover and hypogonadism.

Absorptiometry, Photon↗

PubMed1994

[Peptic ulcer: changing indications for gastric resection during the last 15 years].

In this study the authors want to underline the changing strategies for peptic ulcer disease. Considering the experience of two Surgery Departments in Piedmont, the G. Bosco Hospital of Turin and the S. Croce Hospital of Moncalieri, in the last 15 years, they observed a notable reduction of gastric resections owing to new drugs such as H2-antagonist and omeprazole in peptic ulcer therapy. The authors report, therefore, recent suggestions to gastric resection in the cases of complicated ulcer or not. Today pyloric stenosis due to chronic ulcer no longer operated and perforated ulcer is resected only when there is a great gastric hole, or a relapse perforation or a bleeding together to perforation. On the contrary hemorrhagic ulcer is operated when the bleeding is either notable, or relapse, or continuous, or untransfusible.

Histamine H2 Antagonists↗

PubMed1994

[Carotid vascular structural changes and left ventricular hypertrophy].

In the literature there are few studies evaluating carotid vascular atherosclerotic involvement in patients with essential arterial hypertension. Nowadays with new non-invasive methodological methods, such as Doppler-echotomography, it is possible to evaluate accurately structural vascular and cardiac changes. In this study we evaluated the relationship between carotid vascular structural changes and cardiac left ventricular mass index in 15 normotensive subjects and in 15 patients with essential hypertension. We performed a B-mode echotomography (7.5 MHz) of a common carotid in order to measure the diameter of the vessel and intima-media wall thickness. In the same subjects we determined echocardiographic left ventricular mass index and we measured arterial pressure by sphygmomanometric method. There was no statistical significant difference in the two groups except that in systolic, diastolic and mean arterial pressure (96 +/- 2 vs 123 +/- 2 mmHg, p < 0.01), left ventricular mass index (102 +/- 3 vs 118 +/- 3 g/m2, p < 0.01) and in the common carotid intima media wall thickness (0.91 +/- 0.01 vs 2.23 +/- 0.02 mm). In the normotensive subject mean arterial pressure correlated significantly with age (r = 0.699) and with common carotid arterial diameter (r = 0.523) (both p < 0.05). In hypertensive patients, on the contrary, mean arterial pressure correlated with left ventricular mass index (r = 0.523), carotid arterial diameter (r = 0.627) and common carotid intima media wall thickness (r = 0.847). These results demonstrate that in hypertensive patients cardiac abnormalities accompanied vascular structural changes.

Carotid Arteries↗