PubMed Health⌕ Search

Biomedical subjects

G Cunin

Publications and source records attributed to G Cunin.

16 recordsLinked to original sources

Experimental vertebroplasty using osteoconductive granular material.

STUDY DESIGN: Osteoporotic human cadaveric thoracic vertebral bodies and vertebral bodies from mature sheep were used as model systems to assess coral resorption and new bone formation after injection of coral granules. OBJECTIVE: To evaluate the use of natural coral exoskeleton, an osteoconductive material, for the filling of vertebral bodies. SUMMARY OF BACKGROUND DATA: Percutaneous injection of polymethylmetacrylate (PMMA) is often proposed for prophylactically stabilizing osteoporotic vertebral bodies at risk for fracture or augmentation of vertebral bodies that have already fractured. Recently, the possibility of using osteoconductive materials in granular formulation was assessed in pilot studies. METHODS: As a first step, the possibility of injecting coral granules percutaneously within osteoporotic human cadaveric thoracic vertebral bodies was assessed. As a second step, cavities were drilled into vertebral bodies of 10 mature ewes and were either left empty (control group) or filled with coral alone (CC) or coral supplemented with fibrin sealant (CC+FS). Quantitative evaluation of coral resorption and new bone formation was made 2 months and 4 months after implantation. RESULTS: The distribution of coral granules injected into human cadaveric thoracic vertebral bodies was homogenous as assayed radiographically. In the experimental animal model, osteogenesis was increased in cavities filled with coral in comparison with cavities left empty at both 2 months and 4 months (P < 0.005 and P < 0.02, respectively). Surprisingly, supplementation of coral with a fibrin sealant had no positive influence on osteogenesis (P < 0.0008 at 2 months; P < 0.002 at 4 months). In addition, it led to an increase in coral resorption by as soon as 2 months (P < 0.0008). CONCLUSION: These results demonstrate the osteoconductivity of coral in granular form for vertebral filling. Interestingly, interconnectivity between adjacent bone trabeculae and newly formed bone was restored; however, its mechanical significance remains to be determined. Further investigations are needed to evaluate the efficacy of coral in osteopenic animals and in relieving pain.

Aged↗

Efficacy and safety of sumatriptan tablets (25 mg, 50 mg, and 100 mg) in the acute treatment of migraine: defining the optimum doses of oral sumatriptan.

That sumatriptan tablets are effective and well tolerated in the acute treatment of migraine has been established, but the relationship between dose and efficacy has not been adequately defined to date in clinical trials. This multinational double-blind trial (N = 1003) in which patients treated up to three migraine attacks with sumatriptan 25 mg, 50 mg, 100 mg, or placebo, with a second independently randomized dose for headache recurrence, evaluated the efficacy and tolerability of three doses of sumatriptan. The results demonstrate that all doses of sumatriptan were superior (P < 0.05) to placebo in reducing moderate or severe predose headache to mild or no headache 4 hours postdose for each of the three treated attacks; sumatriptan 50 mg and 100 mg were each superior (P < 0.05) to sumatriptan 25 mg 4 hours postdose for two of three attacks. Sumatriptan (all doses) was similarly effective at relieving nausea and photophobia or phonophobia or both and at reducing clinical disability. Headache recurrence was experienced by similar proportions of patients across treatment groups (35% to 48% after placebo; 26% to 39% after sumatriptan). Relief of recurrent headache 2 hours after the second dose of study medication occurred in greater percentages of patients using any dose of sumatriptan compared with patients using placebo to treat recurrence. The incidence of adverse events with 25-mg and 50-mg sumatriptan tablets was similar to the incidence with placebo and lower than the incidence with 100-mg sumatriptan tablets. These data provide the first demonstration from a large well-controlled clinical trial that both the 50- and 100-mg doses are more effective than the 25-mg dose and that the 50-mg dose is associated with a lower incidence of adverse events than the 100-mg dose.

Adolescent↗

Cerebral vasodilation after the thermocoagulation of the trigeminal ganglion in humans.

The resulting changes in the regional cerebral blood flow of 18 patients suffering from idiopathic trigeminal neuralgia and treated by selective thermocoagulation of the trigeminal ganglion were measured by xenon-133 emission tomography. One hour after thermal stimulation, there was an asymmetric increase (P < 0.05) in cerebral blood flow, with a 14.7% mean increase in the ipsilateral cerebral hemisphere (P < 0.001) and a 12.7% mean increase in the contralateral side (P < 0.01). The increase in regional cerebral blood flow was not uniform but was most marked in the ipsilateral middle cerebral artery territory (P < 0.001). There was a slight decrease in cerebellar blood flow, but the reduction in the ipsilateral cerebellar lobe was less than that in the contralateral lobe (P < 0.01). The topography of the most significant changes coincided with that of the innervation of the cerebral vessels by the trigeminal nerve. Several mechanisms are involved in the increase in regional cerebral blood flow, including overall nonspecific activation of the central nervous system and local mechanisms associated with the trigeminal-vascular system.

Adult↗

Levels of morphine and metabolites in CSF during respiratory depression after intraventricular morphine injection.

We report a case of respiratory depression after intracerebroventricular morphine administration of a dose inadvertently 10 times greater than the typical daily dose. At the time of the respiratory dysfunction, the concentrations of morphine and its metabolites in cerebrospinal fluid (CSF) and plasma samples were determined. On comparison of these results with previous clinical studies in which there was no respiratory depression, no relationship was found between the occurrence of respiratory depression and the concentration of morphine or its metabolites in the CSF. The occurrence and characteristics of respiratory depression may be related to the concentrations of morphine and its metabolites in bulbar tissue.

Adenocarcinoma↗

[Treatment of intractable pain in ORL cancer].

Numerous effective treatments are available to relieve the intractable pain of terminal E.N.T. cancers when aetiological therapies are no longer of any use. These treatments must be prescribed as a progressive therapeutic scale ranging from analgesics, and notably morphine which remains the basic drug, to the classical or stereotactic surgical operations. To these must now be added other routes of administration of morphine (e.g. intraventricularly) which in some cases give unexpected results.

Humans↗

[A neurosurgeon's point of view on lumbago].

Low back pain is an important health and economic problem which plagues a large segment of the population of industrialized countries. Etiologic theories based upon tissue damage, and therapeutic measures aimed at eliminating a presumed noxious stimulus are often not efficacious. There is considerable evidence that social and psychological factors play a major role in the symptom complex known as "Low Back pain".

Adult↗

[Effects of delayed-action tetracosactide on chronic pain].

Beta 1-24 corticotrophin was the object of an open trial in the "acute" treatment of chronic pain in 22 patients. The analgesic effect of the drug was assessed before and after two weeks of treatment by means of 3 subjective tests: visual analogue scale, numeric scale and Mac Gill pain questionnaire. The results were statistically significant (P less than 0.01). They confirmed that slow-release tetracosactide exerts a beneficial effect on the sensory-discriminative and affective-emotional components of pain. The drug may be prescribed for short periods (1 to 2 weeks) to patients with chronic pain refractory to the usual treatments. Its analgesic effect is immediate and enables a conventional treatment to be instituted.

Chronic Disease↗