PubMed Health⌕ Search

Biomedical subjects

R Viola

Publications and source records attributed to R Viola.

28 records · Page 2Linked to original sources
PubMed1993

Regional and systemic prophylaxis with teicoplanin in monolateral and bilateral total knee replacement procedures: study of pharmacokinetics and tissue penetration.

Twenty-four patients undergoing monolateral or bilateral total knee replacement (TKR) procedures were randomized to receive teicoplanin (T) either systemically or regionally. Subjects scheduled for systemic prophylaxis and undergoing monolateral (six patients) or bilateral (five patients) TKR received a single 800-mg dose of T in 100 ml of saline as a 5-min infusion into a forearm vein 2.5 h before surgery. For regional prophylaxis, patients undergoing monolateral surgery (eight subjects) received 400 mg of T in 100 ml of saline as a 5-min infusion into a foot vein of the leg to be operated on immediately after the tourniquet was inflated. For the five patients scheduled for bilateral operation and regional prophylaxis, the administration of T was also repeated for the second knee operation. The tourniquet, as the standard TKR surgical technique, was inflated to 400 mm Hg (c. 50 kPa) in all 24 patients immediately before the beginning of surgery and kept in place for the duration of the operation. Samples of serum, bone, skin, synovia, and subcutaneous tissue were collected at timed intervals during surgery. They were microbiologically assayed for T by using Bacillus subtilis as the test organism. Overall, the mean T concentrations obtained with regional route prophylaxis were found to be 2 to 10 times higher than those achieved following systemic prophylaxis. Moreover, peak levels in different tissues after regional prophylaxis were significantly higher (P < 0.05). None of the patients experienced adverse effects due to regional or systemic T administration; no prosthetic or wound infections were observed in the follow-up period (from 12 to 26 months).

Aged↗
PubMed1991

Fluoride-Induced Inhibition of Starch Biosynthesis in Developing Potato, Solanum tuberosum L., Tubers Is Associated with Pyrophosphate Accumulation.

Pretreatment of discs excised from developing tubers of potato (Solanum tuberosum L.) with 10 millimolar sodium fluoride induced a transient increase in 3-phosphoglycerate content. This was followed by increases in triose-phosphate, fructose 1,6-bisphosphate and hexose-phosphate (glucose 6-phosphate + fructose 6-phosphate + glucose 1-phosphate). The effect of fluoride is attributed to an inhibition of glycolysis and a stimulation of triose-phosphate recycling (the latter confirmed by the pattern of (13)C-labeling [NMR] in sucrose when tissue was supplied with [2-(13)C]glucose). Fluoride inhibited the incorporation of [U-(14)C] glucose, [U-(14)C]sucrose, [U-(14)C]glucose 1-phosphate, and [U-(14)C] glycerol into starch. The incorporation of [U-(14)C]ADPglucose was unaffected. Inhibition of starch biosynthesis was accompanied by an almost proportional increase in the incorporation of (14)C into sucrose. The inhibition of starch synthesis was accompanied by a 10-fold increase in tissue pyrophosphate (PPi) content. Although the subcellular localization of PPi was not determined, a hypothesis is presented that argues that the PPi accumulates in the amyloplast due to inhibition of alkaline inorganic pyrophosphatase by fluoride ions.

Journal Article↗
PubMed1991

Aldosterone-secreting adenoma and dysautonomic failure: the challenging association of 2 extreme conditions.

This is the first published report describing the association between primary aldosteronism and chronic idiopathic orthostatic hypotension. The clinical history of a 57 year old man with incapacitating postural hypotension and severely symptomatic supine hypertension, is described. A possible occupational etiology of postural hypotension, with regard to a prolonged exposure to cutting oils, is considered. The intriguing pathophysiologic aspects of this unique association are discussed. The Authors suggest that, although supine hypertension is common in chronic idiopathic orthostatic hypotension, a careful examination of the adrenal glands is advisable in these patients, to rule out the presence of an associated adrenal adenoma.

Adenoma↗
PubMed1990

Immunohistochemical study of neuropeptide Y-containing nerve fibers in the human clitoris and penis.

The occurrence and distribution of neuropeptide Y in the human clitoris and penis was investigated by light immunohistochemistry. Neuropeptide Y-containing nerve fibers were detected in the tunicae of arteries and veins as well as among trabecular smooth muscle. The distribution pattern of the peptide was similar in both organs although a higher density of immunoreactive nerve fibers was detected in the penis. The immunolocalization of neuropeptide Y was also compared with that of neuron-specific enolase, a neuronal marker which labels the entire nerve network. It is suggested that neuropeptide Y is involved in the physiology of the penis and the clitoris, affecting vascular and nonvascular smooth muscle activity.

Adolescent↗
PubMed1990

[Hypomagnesemic coma in heart failure: description of a case].

The case of a patient developing hypomagnesemic encephalopathy and coma secondary to intensive treatment for severe cardiac failure, is reported. Following an early improvement of symptoms and signs of cardiac failure, a rapidly developing neurologic disorder appeared. This was characterized by insomnia, agitation, mental derangement and, finally, sopor and I-II degree coma. Serum magnesium concentration was 1.0 mEq/l. Magnesium sulfate iv infusion was followed by a immediate and complete recovery from the neurological disorder. Patients with cardiac failure undergoing prolonged intensive therapy are prone to develop hypomagnesemia. This electrolyte alteration may be responsible for symptoms and signs of central nervous system involvement (metabolic encephalopathy) that need to be differentiated from those of organic origin.

Coma↗
PubMedDate not supplied

Combined MR-relaxation and MR-cryoporometry in the study of bone microstructure.

MR-Relaxation (MRR) of 1H nuclei and MR-Cryoporometry (MRC) are combined to assess their feasibility and their potential in the study of bone microstructure. In principle, both techniques are able to give information on the structure of the pore space confining the fluids. Cow femur samples were carefully cored and cleaned in order to remove the natural fluids inside. For MRR analysis quasi-continuous distributions of T(1) and T(2) were obtained on samples fully saturated with water. Cyclohexane was used as a saturating fluid for MRC analysis. All T(1) and T(2) quasi-continuous distributions of water confined in bone samples are more than three decades wide, showing sufficient details to differentiate the samples. Pore size distributions obtained by MRC also differentiate the samples showing different characteristics of the pore space structure in the range of the highest sensitivity of the method (typically 3 to 100 nm, mesopore range). In particular, in samples where MRR shows a large fraction of signal with relaxation times below 10(2) ms, MRC indicates a large fraction of pore volume with pore sizes in the mesopore range.

Animals↗
PubMedDate not supplied

Three cases of patella fracture in 1,320 anterior cruciate ligament reconstructions with bone-patellar tendon-bone autograft.

Between September 1992 and December 1996 we reviewed three transverse displaced fractures of the patella occuring in 1,320 ACL reconstructions using bone-patellar tendon-bone autograft. All the patients suffered local injury to the donor knee between 8 and 12 weeks postoperatively. Immediate rigid fixation using single or double anterior tension band allowed early mobilization and full weight bearing. Between 6 and 9 months after fracture, the screws and the wire were removed and the grafts tested. Results of the pivot shift and Lachman test under anesthesia were negative and arthroscopic visualisation showed the graft to be intact. Postoperative assessment included the Lysholm and Tegner scales, the International Knee Documentation Committee Evaluation form (IKDC), KT-1000 arthrometer, and isokinetic dynamometer strength testing. No significant differences in the final outcome were noted between reconstructions complicated by patellar fracture and normal ACL reconstructions.

Adult↗