Biomedical subjects

R Donzelli

Publications and source records attributed to R Donzelli.

41 records · Page 3Linked to original sources

PubMed1978

[The pseudo-vascular syndrome of intracrânial metastases (author's transl)].

Our statistic consist of 162 cases of metastatic tumors of the brain (M.T.B.), of which 120 verified under surgery or at autopsy, and 42 diagnosed in the pre-operative phase and not undergone surgery. The pseudo-vascular form has been found in 58 cases (36%). If we only consider the supratentorial localizations, this percentage rises to 43,5%. This onset of symptomatology is quite predominant in males (52 cases 42%) compared to females (6 cases: 16%). The MTBs that in our statistics produce a greater frequence of pseudo-vascular forms are the MTBs of melanomas (66%), those of unknown origin (42%) and those of pulmonary origin (35%). These neoplasms are distinctly more frequent in males. On the contrary the mammary metastases responsible for most of the female MTBs originate to a pseudo-vascular form in only 22% of the cases. The etio-pathogenetic mechanism is double; it may be the manifestation either of arterial occlusion by neoplastic cells (embolia neoplastica attiva) or of disruption of the vascular wall and hemorrhage. As far as the diagnosis is concerned this syndrome can be quite easily recognised only when an extraneuraxial tumor is found, especially with a marked neuraxial tropism.

Adult↗

PubMedDate not supplied

Action of glucomannans on complaints in patients affected with chronic constipation: a multicentric clinical evaluation.

Chronic constipation is a very frequent disease in western countries but fibres can often solve the problem. In the present study, authors tested the efficacy and the acceptability of glucomannans, hydrophylic carbohydrates with a high degree of viscosity, in 93 patients affected with chronic constipation. The multicentric, open and non-controlled study was divided into an initial phase (treatment with 1g of glucomannans t.i.d. for 1 month) and a maintenance phase (1g b.i.d. for one month). We evaluated both objective parameters (number of days per week with bowel movements and number of enemas) and abdominal symptoms. After one month all assessed parameters showed a statistically significant improvement lasting through the second month. Glucomannans were well accepted and devoid of relevant side-effects. In conclusion, considering their efficacy and tolerability, they can be proposed as an ideal therapeutic tool in the management of chronic constipation symptoms.

Adult↗

PubMedDate not supplied

Paramedian hourglass epidermoid cysts extending in the middle and posterior cranial fossa.

Four cases of large paramedian hourglass epidermoid tumors extending both in the middle and posterior cranial fossa are reported and other 16 cases from the literature are reviewed. The length of the clinical history and the triviality of neurological symptoms in spite of the size of the tumor are emphasized. CT scanning well documents the extension of these epidermoids and usually consents to differentiate them from the arachnoid cysts. The subtemporal transtentorial approach is more advisable, although a two-stage operation by subtemporal and suboccipital route can be necessary in some cases. Nevertheless the difficulties and the risk of the surgical treatment make very hard the complete removal of the tumor in most cases.

Adult↗

PubMedDate not supplied

Experimental model of nervous anastomosis between intercostal and lumbar nerves in the rabbit.

The authors propose a new experimental model of nervous anastomosis between intercostal and lumbar nerves in rabbit with the purpose of providing a technique to by-pass a spinal lesion. Before carrying out the surgical experiments, an histological study has been performed on the donor and receiver nerves which demonstrated the great difference in number of nervous fiber between these two nerves. The purpose of the method is thus to reinnerve a lumbar nerve by means of two intercostal nerves. Histological controls are performed on the 120th day.

Animals↗

PubMedDate not supplied

Light and laser scanning microscopy analysis of hydroxyapatite used in periodontal osseous defects in man: evidence of a different resorption pattern in bone and soft tissues.

Hydroxyapatite (HA) is a highly biocompatible material that recently has been shown to undergo biodegradation. The mechanisms of this phenomenon are unclear, and humoral and cellular events have been thought to be implicated. In the present study HA particles were put into infraosseous defects on teeth that were to be extracted for prosthetic reasons and then retrieved after a 1-year period. The specimens were processed with the cutting grinding system. Results show a very sharp difference of the biodegradation processes, related to the tissues that surround the HA particles. HA in tight contact with mineralized bone showed no evidence of degradation or resorption, while on the contrary, in the areas where bone loose connective tissue was present, it was possible to observe HA crystals detached and scattered in cells cytoplasm or extracellular fluids. This dissolution and resorption phenomenon were observed also by Laser Scanning Microscope (LSM) in fluorescent mode. These differences in degrees of degradation between bone and loose connective tissue could be due to the small amount of interstitial fluid present in mineralized bone and the greater flow of fluid through connective tissue.

Biodegradation, Environmental↗