Intravenous cidofovir treatment for recalcitrant warts in the setting of a patient with myelodysplastic syndrome

Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.     

Cyclodextrin formulation of dorzolamide and its distribution in the eye after topical administration.

Due to limited aqueous solubility of dorzolamide at physiologic pH, the pH of Trusopt eye drops (cont. 2% dorzolamide) has to be kept at about 5.65, and to increase the topical bioavailability of the drug from Trusopt the contact time of the drug with the eye surface is increased by increasing the viscosity of the eye drops to 100 cps. This low pH and high viscosity can lead to local irritation. In this study, dorzolamide hydrochloride was formulated as 2% and 4% low viscosity solutions (viscosity 3 to 5 cps) containing randomly methylated beta-cyclodextrin at pH 7.45. These formulations were evaluated in rabbits. The animals were sacrificed at various time points after topical administration of the drug and the dorzolamide concentration determined in the different parts of the eye. Trusopt was used as a reference standard. The topical availability of dorzolamide from the cyclodextrin-containing eye drops appeared to be comparable to that from Trusopt and the drug reached retina and optic nerve to give measurable concentrations for at least 8 h after administration of the eye drops.     

Olfactory Absorption of Insulin to the Brain

A vast number of potent neuropharmaceuticals, many of which are peptides, are excluded from entry into the brain because of the highly selective blood-brain barrier. The fact that a number of drugs have been shown to be transported directly to the central nervous system following application to the olfactory region of the nose is therefore of major interest. In the present study, the feasibility of delivering peptides to the brain via the olfactory route was assessed using insulin as a model peptide. Systemic hyperinsulinemia induced by subcutaneous injection did not significantly reduce the amount of ¹²⁵I-insulin transported from the nose to the brain in vivo, which suggests that the impact of systemic absorption on drug transport is minimal. A linear relationship was seen between insulin accumulation in the brain and the dose applied, without any relevant saturation. Contrary to what was expected, both systemic and olfactory absorption of insulin was enhanced when the pH of the medium was near the isoelectric point. The amount absorbed to the brain was found to be linearly related to the net charge of the molecule (r = -0.61; n = 20). It was concluded that insulin gains access to the central nervous system from the olfactory region of the nose by a nonspecific pathway. The olfactory route may therefore become an important means to deliver peptides to the brain.     

Intraaortic balloon tamponade during hemorrhagic shock in sheep

Two groups (n = 10 in each) of adult sheep were exposed to hemorrhagic shock resulting in mean arterial pressure (MAP) below 25 mmHg for 10 min. Following that, group A received crystalloids (8% of body wt) during one hr together with supraceliac intraaortic balloon tamponade during the first 30 min, while group B (controls) received crystalloids only. The central circulation was rapidly restored in group A, as indicated by increased MAP and increased systemic vascular resistance (SVR). After deflation of the balloon MAP dropped to the same value as in the control group, while cardiac index increased gradually with volume replacement and was significantly higher at the end of the resuscitation period (60 min) than in the control group (P less than 0.05). Despite a more rapid restoration of central hemodynamics in group A, lactic acidosis was more severe, acute renal failure and neurological complications more frequent, and mortality higher than in the control group. It was concluded that continuous supraceliac aortic occlusion for 30 min had deleterious effects on organs dependent on aortic blood flow distal to the aortic tamponade and may contribute to the development of multiple organ failure after resuscitation from hemorrhagic shock. Further studies are needed to evaluate the effects of intermittent intraaortic balloon tamponade in hemorrhagic shock.     

Glial cell line-derived neurotrophic factor-dependent recruitment of Ret into lipid rafts enhances signaling by partitioning Ret from proteasome-dependent degradation

The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.     

Late side-effects with cosmetic relevance following soft X-ray therapy of cutaneous neoplasias

Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.     

The volume-deficient orbit: clinical characteristics, surgical management, and results after extraperiorbital implantation of Silastic block.

The surgical techniques and results after extraperiorbital implantation of Silastic on the orbital floor of 70 patients are reviewed. In 11 patients the implant was through a subciliary approach and in 59 through an inferolateral cantholysis. The inferolateral cantholysis, a simplification of the McCord and Moses approach to the orbital floor, is particularly suited to this application. The implanted Silastic was retained in 66 patients, with an average follow up of 3.5 years (range less than 1 to 9.5 years), though six required surgery to debulk the anterior end of the implant. Further surgery was required in 27 patients, this generally being to correct the position of either the upper or the lower lid. Volume enhancement was effective in most cases, there being a significant reduction in the degree of recession of the prosthesis and the depth of the unsightly sunken sulci of the upper and lower lids. The mobility of the orbital contents, the prosthesis, and the upper lid was not improved.     

HYPOKALEMIA IN THE ELDERLY: IS IT ALWAYS DIURETIC-INDUCED?

SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin.