Nuclear magnetic resonance and its biological problems

Among the main reasons for the interest aroused by the production of images by nuclear magnetic resonance, the successes obtained by TC and the possibility of avoiding the use of ionizing radiations in the new procedure are well worth mentioning. This possibility had induced operators to consider the possible effects of an examination with nuclear magnetic resonance "a priori" unimportant or only noticeable as regards a subjective symptomatology of scarce importance and, at most they advise a few general precautionary measures in the selection of patients. The separate study of the effects of individual forms of energy which act in nuclear magnetic resonance has, however, shown the utility of extending research of tests in wider physiopathological fields and deepening studies of molecular biology, even though results to date appear reassuring.     

Does primary melanoma of the bladder exist?

Primary melanoma of the urinary bladder is a rare neoplasm to which very strict diagnostic criteria apply. Although reports of previous cases exist, these criteria have yet to be met. We report a case of a young lady from whom a malignant melanoma of the bladder was resected. This was presumed to be primary as detailed investigation failed to find any other site from which metastases could have originated. We discuss the diagnostic criteria of this entity and stress the difficulty in conclusively demonstrating that, despite some of these criteria being met, a lesion such as this is primary in origin. This case could be the longest surviving patient with primary melanoma of the bladder, however we will never be able to prove that spontaneous regression of an undiagnosed extravesical primary malignant melanoma did not occur.     

The importance of angiogenesis in ovarian cancer

Advanced stage ovarian cancer has a high rate of recurrence even after surgery followed by chemotherapy combining carboplatin and a taxane. New strategies are currently under way to combat this situation and one of the most promising ones is based on the knowledge that angiogenesis, the mechanism of formation of new blood vessels coupled with the degradation of the extracellular matrix for metalloproteinases, could be crucial in the development of this tumor. The principal molecule implicated in angiogenesis process of ovarian cancer is the vascular endothelial growth factor (VEGF). Several studies are now in progress to clarify its role as a diagnostic tool or its therapeutic implication. Presently, there is no indication for the use of VEGF in a preliminary diagnosis seeing that an increase in levels can be seen in both benign and malignant ovarian conditions. VEGF is also responsible for an increase in vascular permeability and is directly related to symptoms such as ascites and pleural effusion, both of which are frequent in ovarian cancer. Several papers have analised the role of VEGF as a prognostic factor and some of them do confirm VEGF as an independent prognostic factor in ovarian cancer. VEGF and the metalloproteinase system coupled with angiogenesis are currently being evaluated as therapeutic targets but no positive results have yet to be seen in this field.      

High-resolution US of non-traumatic recurrent dislocation of the peroneal tendons: a case report

We report the case of a young girl with recurrent sharp pain in the outer aspect of the ankle. She had no previous trauma. High-resolution US (HRUS) showed a complete intermittent dislocation of the peroneal tendons. Post-traumatic chronic peroneal instability is quite common, whereas complete dislocation is rare. HRUS is an important adjunct to clinical examination and radiographic evaluation of patients with musculoskeletal disorders of the foot and ankle [1]. This paper reports its value in non-traumatic recurrent dislocation of the peroneal tendons. Received: 23 May 1997 Accepted: 1 December 1997     

Pulmonary lymphangiectasia revisited

PURPOSE: Pulmonary lymphangiectasia (PL) is a rare, poorly documented disease characterized by abnormal pulmonary lymphatics. Although case reports are published, little is known about survivors past the neonatal period. METHODS: This is a retrospective review of histologically proven PL in fetuses, infants, and long term survivors since 1965. RESULTS: Eleven children (8 boys, 3 girls) and 8 aborted fetuses (7 male, 1 female) were identified. The fetuses weighed 463.4 g (177 to 681 g). Six were aborted between 19 to 24 weeks of gestation for multiple malformations or anencephaly, and 2 spontaneously aborted: one with PL only, the other with twin-twin transfusion syndrome. Clinical PL was diagnosed between 0 and 11 months of age. Six children died (2 neonatal, 4 within 10 days), 5 survived. Two deaths occurred after cardiac surgery. Among survivors, the symptomatology and frequency of admissions diminished over time. Symptoms included progressive respiratory distress, chronic cough, recurrent pneumonia, bronchial asthma, and choking. One child with bilateral chylothorax was later diagnosed with Noonan syndrome; 2 patients had minor cardiac malformations. Rapid deterioration occurred with mild respiratory infections with only supportive treatment available. Chest x-ray showed marked hyperinflation with interstitial infiltrate. CONCLUSIONS: This is the first long-term study of primary PL and will help counsel parents. Although fatal in the neonatal period, survival is possible if diagnosed past the neonatal period and improvement is expected.     

Management of jugular paragangliomas: the Gruppo Otologico experience.

OBJECTIVE: The objective of this study was to review the outcome of surgical management in patients of jugular paragangliomas. STUDY DESIGN: We conducted a retrospective case review. SETTING: Tertiary care otology and skull base center. MATERIALS AND METHODS: Fifty-five patients with the diagnosis of a jugular paraganglioma (Fisch Class C and D Glomus Jugulare) were managed over a period of 15 years. All patients with adequate follow up and complete records (53 cases) were reviewed with emphasis on the results of surgical management and the factors influencing them. INTERVENTION: All 53 patients were managed with a view to surgically extirpate the tumor. The primary approach was the infratemporal fossa approach-Type A used in the majority of the patients. In eight cases, the procedure was staged owing to the presence of large intracranial extension. Three patients required additional procedures to ameliorate the after-effects of lower cranial nerve resection. RESULTS: Gross total tumor removal was achieved in 49 patients. There were five cases of recurrence. Coupled with the residual tumors in five patients, the surgical control achieved was 83%. There was no perioperative mortality. There were two cases of postoperative cerebrospinal fluid leak, both of which required surgical exploration and closure. The facial nerve was resected in seven patients. The overall preservation rate of clinically uninvolved lower cranial nerves was 75%. CONCLUSIONS: The low level of complications along with a high surgical control achieved makes surgery the primary mode of treatment in the vast majority of these tumors, regardless of the size and location.     

Development of cultured rabbit corneal epithelium for drug permeation studies: a comparison with excised rabbit cornea.

The aim of this study was to prepare and test an artificial corneal epithelium (reconstituted rabbit corneal epithelium, RRCE) exhibiting barrier characteristics and paracellular permeability similar to those of native rabbit cornea. The RRCE was obtained from a rabbit corneal epithelium (RCE) cell line grown for 8 days in submerged culture, then for 7 days in air-interface conditions on Snapwell polyester membranes. Permeation studies on the RRCE were carried out in comparison with rabbit excised corneas in vitro, using timolol maleate (TM) as the test drug, alone and in association with the following ocular permeation enhancers: benzalkonium chloride, ethylene-diaminetetraacetic acid sodium salt, polyethoxylated castor oil, polyoxyethylene stearyl ether, sodium deoxycholate, and escin. The integrity of the RRCE was assessed by measuring the transepithelial electrical resistance (TEER) during culture time and after every permeation experiment. When TM was tested alone, the permeation parameters (apparent permeability coefficient, lag time) obtained with the RRCE were similar to those of excised rabbit corneas. The artificial epithelium, however, was less sensitive than native cornea to the effect of permeation enhancers.