Agents ameliorating or augmenting experimental gentamicin nephrotoxicity: some recent research.

Despite its nephrotoxic potential, the aminoglycoside antibiotic gentamicin (GM) is still considered to be an important agent against life-threatening infections. The goal of reducing or protecting against its nephrotoxicity has attracted much effort and attention during the last decade. This article reviews some of the literature published during the last decade on the effects of agents that ameliorate or augment GM nephrotoxicity. Notable among the ameliorating agents are antioxidant agents. These include different classes of compounds that include beta blockers (e.g. carvedilol), superoxide dismutase mimetic agents (e.g. M40403), hormones (e.g. melatonin), iron chelators (e.g. deferrioxamine), vitamins (vitamin C and E) and medicinal plants (e.g. garlic). Other ameliorating agents include antibiotics (e.g. ceftriaxone), antiplatelet drugs (e.g. trapidil) and Ca++ agents that may augment GM nephrotoxicity include cyclosporin and the Ca++-channel blocker verapamil.     

Gastrointestinal transit in mice treated with various extracts of date (Phoenix dactylifera L.).

Dates are commonly consumed, especially in the Middle East, but their effect on gastrointestinal transit (GIT) has not been quantified. The effect of water and ethanol extracts from date flesh and date pits on the GIT in mice was studied. Fasted unanaesthetized male mice received by gavage either the vehicle (0.02 m/kg), or the extracts at doses of 0.01, 0.02 or 0.04 ml/kg. Two separate groups received either clonidine (1 mg/kg) or yohimbine (2 mg/kg). Two hours later, all animals were given a test meal containing charcoal and gum arabic in water. Thirty min thereafter, they were killed and the distance the charcoal column had traveled along the small intestine was measured. Compared with the control, the animals that received the ethanol and water extracts of both date flesh and pits emptied, in a dose-dependent manner, more of their gastrointestinal content. The increase in the GIT ranged from 4 to 22%. However, water extract from dialyzed date flesh induced a dose-dependent decrease in GIT that ranged from 4 to 24%. Clonidine exerted a significant decrease (68%), and yohimbine a significant increase (30%) in the GIT. Depending on the method of extraction, the date extracts may exert an increase or a decrease in GIT.     

Structure and Behavior in Hydrophilic Matrix Sustained Release Dosage Forms: 4. Studies of Water Mobility and Diffusion Coefficients in the Gel Layer of HPMC Tablets Using NMR Imaging

Purpose. The purpose of this study was to characterise the water mobility in the gel layer of hydrating HPMC tablets. Water mobility in the gel layer of different HPMCs was studied. Methods. NMR imaging, a non-invasive technique, has been used to measure the spatial distribution of self-diffusion coefficient (SDC) and T₂ relaxation times across the gel layer. Results. It has been shown that there is a water mobility gradient across the gel layer of HPMC tablets. Although SDC and T₂ relaxation times in the outer parts of the gel layer approached that of free water, in the inner parts they decreased progressively. Water mobility and SDC in the gel layer of different HPMCs appeared to vary with degree of substitution of the polymer and the lowest values were obtained across the gel layer of K4M tablets. Conclusions. Water mobility varies across the gel layer of hydrating HPMC tablets and it is dependent on the degree of substitution of the polymer.     

Topical steroid use in the treatment of ocular alkali burns

BACKGROUND—Ocular alkali burns can be associated with a poor visual outcome. The release of collagenases and proteases after the injury leads to corneoscleral melting. The role of topical steroids in such patients is controversial as they have been postulated to exacerbate corneoscleral melting.
METHODS—30 patients were reviewed retrospectively after admission to King's College Hospital with alkali burns between 1990 and 1993. All patients were treated with an intense and prolonged regimen of topical steroids and topical and systemic vitamin C.
RESULTS—22 patients had mild injuries and eight had severe injuries as estimated by the Roper-Hall grading system. 23 patients were treated with topical steroids for > 10 days and 22 patients were treated with topical vitamin C for more than 10 days. One patient with a severe injury developed corneoscleral melting.
CONCLUSION—Prolonged treatment with topical steroids when used in conjunction with topical vitamin C is not associated with corneoscleral melting.

     

Nodus migrans: the case of the migrating knot.

Flow-directed pulmonary artery catheters provide important information regarding intravascular volume status, cardiac function and vascular resistance. We describe an unusual complication of pulmonary artery catheterization in which a knot formed at the distal end was torn away from the catheter body and migrated from its original position in the right subclavian vein to a distal branch of the right pulmonary artery. Careful attention to insertion and withdrawal techniques could prevent this potentially serious complication.     

Locked intramedullary nailing for complex non-union of the tibia

Ten patients with complex non-union of the tibia were treated by locked intramedullary nailing. These patients had scarred skin as a result of initial severe open fractures, multiple debridement or fasciotomies with external fixators and skin grafts applied. Seven of the patients also had previous osteomyelitis or pin track infections. Fully pain-free walking was achieved in all patients and radiological union in nine patients without the need for a bone graft. Four patients developed infection after nailing, of which three resolved with treatment.     

Comparison of CT-guided sclerotherapy with using 95% ethanol and 20% hypertonic saline for managing simple renal cyst.

OBJECTIVE: We wanted to compare the efficacies of 95% ethanol and 20% hypertonic saline (HS) sclerotherapies that were performed in a single session under CT guidance for the management of simple renal cysts. MATERIALS AND METHODS: A prospective series of 74 consecutive patients (average age: 57.6 +/- 8.1 years) with simple renal cysts were enrolled in this study. They were randomized into two groups and 95% ethanol or 20% HS, respectively, corresponding to 25% of the aspiration volume, was injected. Treatment success was determined six months later with follow-up clinical evaluation and performing ultrasonography. RESULTS: The sclerotherapy was accepted as technically successful without major complications in all except two patients who were excluded because of a communication between the simple renal cyst and the pelvicalyceal collecting system. Thirty-six patients in the ethanol group received sclerotherapy with 95% ethanol and 36 patients in the HS group underwent sclerotherapy with 20% HS. The complete regression ratio of the ethanol group was significantly higher (94% versus 72%, respectively) than that of the HS group. There was one patient with partial regression in each group. The failure ratio of the ethanol group was significantly lower (3% versus 25%, respectively) than that of the HS group. CONCLUSION: Ethanol sclerotherapy under CT guidance is a successful and safe procedure and it can be used for the treatment of simple renal cysts. Sclerotherapy with 95% ethanol is more effective than 20% HS sclerotherapy. Sclerotherapy with HS may be an option for patients preferring to undergo a less painful treatment procedure.