Differential Stripping: Determination of the Amount of Topically Applied Substances Penetrated into the Hair Follicles

The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively.     

Mechanism of uptake and retention of F-18 BMS-747 158-02 in cardiomyocytes: a novel PET myocardial imaging agent

Background BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02 was studied in vivo in mice. Methods and Results Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC₅₀ of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC₅₀ of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%) and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC₅₀ value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t_1/2) uptake was very rapid (approximately 35 seconds), and washout t_1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02 had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization and demonstrated sustained myocardial uptake through 55 minutes. Conclusions F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake and slow washout. These characteristics allow fast and sustained accumulation in the heart.     

Cabergoline compared to levodopa in the treatment of patients with severe restless legs syndrome: results from a multi-center, randomized, active controlled trial.

We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline.     

Pressure stability of nasal CPAP and bilevel devices

Summary Question of the study   Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods   The CPAP devices were set to a pressure level of 9.8  hPa (10  cm H₂O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results   Mean CPAP pressures differed between the devices (9.9 – 10.6  hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8  hPa and increased during expiration to 11.1 – 11.7  hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19  hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16  hPa. Inspiratory pressures dropped to 8.5 – 4.5  hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions   Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated.     

The role of complement, C5a and its receptors in sepsis and multiorgan dysfunction syndrome.

Sepsis continues to be a major clinical problem that is difficult to treat, as the pathophysiology of the disease is still unclear. Despite promising experimental strategies, therapeutic interventions have been largely unsuccessful. There is now increasing evidence that the disturbance of innate immunity during sepsis and multiorgan dysfunction syndrome (MODS) may be linked to uncontrolled activation of the complement system. Especially, the powerful anaphylatoxin C5a seems to play a key role in the development of immune paralysis. In this review, we describe our present understanding of the role of complement in the inflammatory response during sepsis and MODS.     

Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial.

Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function.     

Statistical properties of the allelic and genotypic transmission/disequilibrium test for multiallelic markers

The transmission/disequilibrium test (TDT) is extended in two ways for a multiallelic marker: (1) to compare transmitted and nontransmitted alleles from a single heterozygous parent and (2) to compare genotypes formed by the two transmitted alleles and genotypes formed by the two nontransmitted alleles using the information on both parents, heterozygous or not, simultaneously. © 1995 Wiley-Liss, Inc.     

Interleukin-4 as a potent down-regulator for human alveolar macrophages capable of producing tumour necrosis factor-alpha and interleukin-1.

The effects of recombinant human interleukin-4 (IL-4) on the production of interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF alpha) by human alveolar macrophages (AM) and autologous peripheral blood monocytes (PBM) in response to lipopolysaccharide (LPS) were examined. AM and PBM were obtained by bronchoalveolar lavage and centrifugal elutriation, respectively, from healthy donors. The production of IL-1 (alpha and beta) and TNF alpha by human AM and PBM were quantitated by enzyme immunoassays (EIA). When activated with LPS, AM secreted much more TNF alpha, but less IL-1 beta than PBM. The production of IL-1 (alpha and beta) by activated AM and autologous PBM was suppressed dose-dependently by IL-4. The inhibitory effect of IL-4 was greatest when it was added to AM or PBM simultaneously with LPS or within 3 h after LPS. The suppressive effect of IL-4 was completely neutralized by pretreatment with rabbit anti-IL-4 antiserum. IL-4 also suppressed the production of IL-1 and TNF alpha by monocyte-derived macrophages. As measured by thymocyte co-stimulation assay, the production of cell-associated IL-1 was inhibited by coculture of AM plus LPS with IL-4. Northern blot analysis showed suppression by IL-4 of expression of messenger ribonucleic acid (mRNA) for IL-1 and TNF alpha in LPS-stimulated AM. We conclude that IL-4 is a potent down-regulator for human alveolar macrophages capable of producing IL-1 and TNF alpha.