New treatment of dry eye: the effect of calcium ointment through eyelid skin delivery.
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AIM: To demonstrate the efficacy of a petrolatum based calcium ointment applied to the lower lid skin in the management of dry eye. METHODS: In a controlled double masked study, the effects of water free petrolatum ointment containing calcium carbonate (10% w/w) on tear functional factors and ocular surface vital staining in dry eye patients were observed. Petrolatum without calcium carbonate served as control. Patients were instructed to place ointment to the lower lid skin twice a day. Evaluation of subjective complaints, fluorescein and rose bengal staining patterns, blink rate, tear evaporation and tear break up time (BUT) were performed before and 3 months after treatment. In order to demonstrate the movement of petrolatum from the skin to the tear film, petrolatum containing 1% sodium fluorescein was placed on the lower lid of four healthy volunteers, and the concentration of fluorescein in the tear film was followed up to 6 hours using an anterior fluorometer. RESULTS: Subjective symptoms significantly improved in both the calcium group (p=0.001) and control (p=0.012), while only the calcium group demonstrated a significant improvement in fluorescein (p=0.043), rose bengal (p=0.021) scores, and blink rate (p=0.004). Tear evaporation also significantly decreased in both the calcium group (p=0.0004) and control (0.043). BUT did not improve in either group. CONCLUSION: Petrolatum based calcium ointment significantly improved symptoms, tear dynamics, and ocular surface staining in dry eye patients. However, some of the therapeutic effects may be due to lipids in the petrolatum vehicle. Petrolatum applied to the lower lid skin is an effective drug delivery system for slowly releasing drugs to the ocular surface. (+info)
Three-dimensional odor tracking by Nautilus pompilius.
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The 'living fossil' Nautilus pompilius is thought to use olfaction as its primary sensory system during foraging, yet neither the organs responsible for olfaction nor the mechanisms or behaviors associated with odor tracking have been subjected to experimentation. Flume testing under dark conditions revealed that Nautilus could consistently detect and follow turbulent odor plumes to the source over distances up to 10 m, exhibiting two types of orientation behavior while sampling in three dimensions. The paired rhinophores were necessary for orientation behavior: when they were temporarily blocked either uni- or bilaterally, Nautilus detected odor but could not track the plume and locate the source. Animals that were tested post-blockage were able to track and locate the source. The role of the 90 thin tentacles remains enigmatic; they seemed to be able to detect odor, but they were not capable of guiding orientation behavior towards a distant odor source. Bilateral chemical sensing by rhinophores in three dimensions may have been the Umwelt of ammonites and belemnites before the evolution of complex eyes and fast locomotion in modern coleoids. (+info)
Efficacy of the inactivation of bacterial spores in white petrolatum and a hydrophilic ointment by gamma irradiation.
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To evaluate the possibilities of using gamma irradiation for the sterilization of ointments, the effect of irradiation on spores of Bacillus pumilus and Bacillus sphaericus in dry material and in two different kinds of ointments was studied. The results indicate that for sterilization purposes irradiation was less effective in white petrolatum as compared to irradiation in the dry state. No such protective effect was found in a hydrophilic ointment. Accordingly, the sterilization dose needed for the sterilization of an ointment can be decided upon only after inactivation experiments with suitable test organisms in the actual preparation. (+info)
Origin of the epidermal calcium gradient: regulation by barrier status and role of active vs passive mechanisms.
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Mammalian epidermis displays a characteristic calcium gradient, with low calcium levels in the lower, basal, and spinous epidermal layers, whereas calcium levels increase progressively towards the outer stratum granulosum, and declining again in the stratum corneum. As the calcium gradient disappears after acute permeability barrier disruption, and returns after 6 h in parallel with barrier recovery, barrier function (through restriction of transcutaneous water movement) could regulate the formation of the epidermal calcium gradient. Two types of experiments confirmed the role of barrier status in regulating the calcium gradient: (i) either a vapor-permeable membrane (Gore-Tex) or an emollient (Vaseline), applied after acute barrier disruption, immediately restored barrier function, while accelerating the return of the calcium gradient, and (ii) in contrast, applications of lovastatin, a cholesterol synthesis inhibitor, which delayed barrier recovery and retarded the return of the calcium gradient. We next asked whether the calcium gradient is formed/maintained by passive and/or active mechanisms. Previous studies have demonstrated that cold exposure (4 degrees C) blocks permeability barrier recovery after acute disruption. Here, we abrogated the barrier with tape-stripping, and then compared barrier recovery and restoration of the calcium gradient in hairless mice exposed to 4 degrees C external temperatures, with and without occlusion with Gore-Tex. Although low levels of returned calcium throughout the epidermis, acutely disrupted, unoccluded, cold-exposed sites showed neither barrier recovery nor reappearance of the calcium gradient at 5 h. In contrast, acutely disrupted, cold-exposed sites, covered with Gore-Tex, likewise displayed little barrier recovery, but the calcium gradient largely returned by 3 h. These results show that (i) barrier status regulates formation of the calcium gradient, and (ii) passive processes alone can account for the formation/maintenance of the calcium gradient. (+info)
Eradication of resident bacteria of normal human skin by antimicrobial ointment.
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The application of a topical triple-antibiotic ointment (containing neomycin, polymyxin, and bacitracin) eradicated resident bacteria through 25 layers of the stratum corneum and prevented repopulation of bacteria overnight but not at 1 week. Through 15 layers, mupirocin had some effect, whereas a double-antibiotic ointment had none. The reservoir of resident bacteria in the sebaceous glands is not affected by a topical antibiotic. (+info)
Modulation of gene expression induced in human epidermis by environmental stress in vivo.
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Environmental insults on the skin induce biologic responses through the modulation of expression of genes implicated in different cell functions. The aim of this study was to investigate the modulation of gene expression profile in human epidermis in vivo following different stresses. We determined the modulations of gene expression using cDNA macroarray in the epidermis of 28 healthy volunteers, following mild and physiologic insults, including: (1), tape stripping; (2) application of 10% sodium dodecyl sulfate; (3) daily application of vaseline; and (4), exposure to one minimal erythema dose of solar-simulated radiation. The analysis was performed 19 h after treatment. The reverse transcription-polymerase chain reaction method was used to confirm our results. We showed that: (1) the intensity of gene modulation was variable among the volunteers following the same skin stress; (2) the nature and intensity of skin treatment modified the pattern of gene expression; and (3) some genes were modulated only by specific stress, some others are modulated irrespective of the stress. GADD45, Bax, SAS, and granulocyte chemotactic protein-2 were overexpressed exclusively following solar-simulated radiation, whereas tape stripping led to the modulation of genes implicated in different pathways (inflammation, cell proliferation, cell differentiation, detoxification, etc.). Concerning common gene modulation, MRP8 and MRP14 were highly upregulated in human skin epidermis after solar-simulated radiation, vaseline application or tape stripping, and to a lower extent after sodium dodecyl sulfate. Such upregulation of the MRP 8/14 genes was confirmed at the protein level in an ex-vivo skin culture model following tape stripping and solar-simulated radiation. Together, these results suggest that MRP8 and MRP14 may be general, yet highly sensitive, markers for a great variety of skin stresses and that they are implicated in several epidermal repair pathways. (+info)
A comparison of cost and efficacy of three incontinence skin barrier products.
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Maintaining healthy, intact perineal skin in nursing home residents with incontinence is a challenge. Their condition puts them at risk for developing incontinence dermatitis, possibly predisposing them to develop pressure ulcers. To examine the cost-effectiveness of three perineal skin barriers (a polymer-based barrier film and two petrolatum ointments) used to prevent incontinence dermatitis, a 6-month descriptive study was conducted among residents (N = 250) from four long-term care facilities (nursing homes) in the upper Midwestern US. All residents were incontinent and had intact perineal skin when they enrolled in the study. An economic analysis was performed using time-motion data from a convenience sample of enrolled residents and their caregivers. Residents had an average of 4.1 (+/-2.307) incontinent episodes per day, the occurrence of incontinence dermatitis was 3.3 % and not significantly different between the different protocols of care (P = 0.4448). Results of the economic analysis showed that daily barrier application costs ranged from $0.17 for the barrier film to $0.76 for the ointments evaluated. With labor included in the analysis, costs were also lower for the barrier film that required the least frequent application ($0.26) compared to ointments that required more frequent application ($1.40). Results of this study suggest that the daily or three times weekly barrier film protocols are affordable alternatives to using petrolatum ointments in the prevention of incontinence dermatitis. (+info)
Comparison of tazarotene 0.1% gel plus petrolatum once daily versus calcipotriol 0.005% ointment twice daily in the treatment of plaque psoriasis.
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Tazarotene and calcipotriol are both effective in the treatment of psoriasis. An investigator-blind, bilateral comparison of 44 lesion pairs in 19 patients was conducted to evaluate the efficacy, side effects and duration of therapeutic effects of once-daily tazarotene 0.1% gel plus petrolatum with twice-daily calcipotriol 0.005% ointment in plaque psoriasis. It consisted of a 12-week treatment phase, followed by a 4-week post-treatment observation phase. At the end of the treatment phase, tazarotene-petrolatum was as effective as calcipotriol in both objective and subjective overall efficacy assessment. Calcipotriol had a significantly greater effect in reducing erythema than tazarotene-petrolatum at weeks 2-8. At week 16, tazarotene-petrolatum demonstrated a significantly better maintenance effect in all parameters. Local irritation was noted only in tazarotene-petrolatum-treated lesions. Once-daily tazarotene 0.1% gel plus petrolatum was as effective as twice-daily calcipotriol 0.005% ointment in the treatment of plaque psoriasis, but had a better maintenance effect after the cessation of therapy. (+info)