Occlusion following laser resurfacing promotes reepithelialization and wound healing

One of the critical parameters that has not been examined carefully following laser skin resurfacing is the effect of eschar on the wound healing process. Because occlusive dressings minimize the occurrence of eschar, the present study was undertaken to evaluate the effect of occlusion following laser resurfacing. It is clear that CO2 lasers promote epidermal cell loss and variable amounts of dermal injury. To characterize the wound repair process after laser treatment, biopsy specimens were obtained 2 to 4 days after treatment. Specimens from 15 patients were examined; the preauricular biopsy specimens were paired such that one specimen was from skin that had been occluded and the other specimen (from the same patient) was from skin treated without occlusion. Skin specimens were examined by indirect immunofluorescence using antibodies to specific epidermal and dermal antigens. The results indicate that the keratinocytes that repopulate the epidermis migrate from the hair follicles and express keratin 17, an intermediate filament protein expressed in keratinocytes during the early stages of wound healing. The migration of keratin 17-expressing cells begins 48 hours following laser resurfacing in skin treated with occlusion, whereas cell migration from the follicles of skin treated without occlusion is delayed. In summary, occlusion promotes enhanced cell migration and diminished eschar formation, resulting in more rapid healing.     

The effect of ovarian steroid deficiency on regeneration of oviductal mucosa following reconstructive surgery

In patients with distal tubal occlusion a microsurgical oviductal reconstruction is, apart from the in vitro fertilization, the only treatment option. Unfortunately, the results of reconstructive surgery are often unsatisfactory. The effects of sex steroids on the regeneration process after reconstructive surgery have not been well investigated. This study was aimed to evaluate the effect of decreased concentrations of ovarian sex steroids (castration) on regeneration of the oviduct mucosa after the reconstructive surgery of distally occluded oviducts. The study was performed on 32 female rabbits that underwent unilateral oviduct ligature and resection of fimbriae. The occlusion lasted six (group I) or twelve weeks (group II). After this time the animals were re-operated, and allocated into 4 groups: castration with reconstructive surgery (IA, IIA), reconstructive surgery only (IB, IIB). After next six or twelve weeks the fallopian tubes were examined under light, scanning and transmission electron microscopes. An immunohistochemical reaction for Ki-67 proliferative antigen was also performed. Ovarian steroid levels were evaluated by radioimmunoassays. The castrated animals had significantly lower levels of estradiol, progesterone and 17-hydroxyprogesterone than the control groups. Long lasting tubal occlusion caused pronounced histological changes of tubal mucous membrane (group II). In the rabbits with preserved ovaries and twelve-week long oviductal occlusion (group IIB), the regeneration of the distal end and restoration of fimbria were not complete twelve weeks after microsurgical reconstruction. In castrated animals with long-lasting occlusion (group IIA) the destructive changes, found in the mucosa of tubal ampullas of occluded oviducts before reconstruction, were still present and even intensified twelve weeks following reconstructive surgery. The castration hampered proliferation of the mucosa cells, thus no fimbriae were restored. Low levels of ovarian steroids were found to have adverse effect on fallopian tube regeneration following reconstructive surgery. The effect was noted even in cases with minor preoperative fallopian tube damage. Therefore, the treatment of concomitant endometriosis or uterine fibroids with GnRH analogues should not be recommended simultaneously with microsurgical tubal reconstruction.     

Topical ‘dual-soft’ glucocorticoid receptor agonist for dermatology

Steroidal glucocorticoids (GR agonists) have been widely used for the topical treatment of skin disorders, including atopic dermatitis. They are a very effective therapy, but they are associated with both unwanted local effects in the skin (skin thinning/atrophy) and systemic side effects. These effects can limit the long-term utility of potent steroids.Here we report on a topically delivered non-steroidal GR agonist, that has the potential to deliver high efficacy in the skin, but due to rapid metabolism in the blood & liver (“dual-soft”) it should have greater systemic safety than existing treatments. In addition, compared to less selective steroidal GR agonists, the new non-steroidal Selective Glucocorticoid Agonists (SEGRAs) have the potential to avoid the skin atrophy observed with existing topical steroids.Due to its potential for reduced skin atrophy and low systemic exposure, LEO 134310 (17) may be suitable for long term topical treatment of skin diseases such as atopic dermatitis and psoriasis.     

Engis: preparation damage, not ancient cutmarks

Scratches found on the Engis 2 cranium have been described as perimortem and interpreted as intentional scalping marks by Russell and LeMort (Am. J. Phys. Anthropol. 69:317-323, 1986). These marks are described and compared to damage on other fossil hominids. The Engis marks have been misinterpreted. These marks are sandpaper striae formed during restoration of the vault, moulding striae formed when mold part lines were incised into the fossil and profiling striae formed when craniograms were made with sharp steel instrument tips. None of them have anything to do with prehistoric behavior.     

Lecithin organogels as a potential phospholipid-structured system for topical drug delivery: A review

The purpose of this review is to give an insight into the considerable potential of lecithin organogels (LOs) in the applications meant for topical drug delivery. LOs are clear, thermodynamically stable, viscoelastic, and biocompatible jelly-like phases, chiefly composed of hydrated phospholipids and appropriate organic liquid. These systems are currently of interest to the pharmaceutical scientist because of their structural and functional benefits. Several therapeutic agents have been formulated as LOs for their facilitated transport through topical route (for dermal or transdermal effect), with some very encouraging results. The improved topical drug delivery has mainly been attributed to the biphasic drug solubility, the desired drug partitioning, and the modification of skin barrier function by the organogel components. Being thermodynamically stable, LOs are prepared by spontaneous emulsification and therefore posses prolonged shelf life. The utility of this novel matrix as a topical vehicle has further increased owing to its very low skin irritancy potential. Varied aspects of LOs viz formation, composition, phase behavior, and characterization have been elaborated, including a general discussion on the developmental background. Besides a comprehensive update on the topical applications of lecithin organogels, the review also includes a detailed account on the mechanistics of organogelling. Published: October 6, 2005     

Dermal excisional wound healing in pigs following treatment with topically applied pure oxygen

Hypoxia, caused by disrupted vasculature and peripheral vasculopathies, is a key factor that limits dermal wound healing. Factors that can increase oxygen delivery to the regional tissue, such as supplemental oxygen, warmth, and sympathetic blockade, can accelerate healing. Clinical experience with adjunctive hyperbaric oxygen therapy (HBOT) in the treatment of chronic wounds have shown that wound hyperoxia may increase granulation tissue formation and accelerate wound contraction and secondary closure. However, HBOT is not applicable to all wound patients and may pose the risk of oxygen toxicity. Thus, the efficacy of topical oxygen treatment in an experimental setting using the pre-clinical model involving excisional dermal wound in pigs was assessed. Exposure of open dermal wounds to topical oxygen treatment increased tissue pO₂ of superficial wound tissue. Repeated treatment accelerated wound closure. Histological studies revealed that the wounds benefited from the treatment. The oxygen treated wounds showed signs of improved angiogenesis and tissue oxygenation. Topically applied pure oxygen has the potential of benefiting some wound types. Further studies testing the potential of topical oxygen in pre-clinical and clinical settings are warranted.     

Quality of life evaluation in Japanese pregnant women with striae gravidarum: A cross-sectional study

ABSTRACT: BACKGROUND: Striae gravidarum is a physiological skin change that many pregnant women experience during pregnancy. The striae are often accompanied by a reddish purple color during pregnancy, and then lose pigmentation and become atrophic in the long term after pregnancy. Striae gravidarum seems to be undesirable to many pregnant women. However, the impact of striae gravidarum on pregnant women who experience it has not been clarified. The aim of this study was to evaluate the impact of striae gravidarum on the generic and dermatology-specific quality of life (QOL) of pregnant women. METHODS: A cross-sectional study was conducted at three private clinics in a typical urban area in Japan. We recruited 447 pregnant women at 36 weeks of gestation; One hundred and ninety-nine pregnant women at 36 weeks of gestation participated in the study and 179, consisting of 94 primiparae and 85 multiparae, were analyzed.We used and assessed Davey's score for striae gravidarum, World Health Organization Quality of Life assessment questionnaire for generic QOL, and Skindex-29 for dermatology-specific QOL. RESULTS: The prevalence of striae gravidarum was 39.1% (27.7% in primiparae, and 51.8% in multiparae). Although there were no differences in generic QOL scores between the presence and absence of striae gravidarum and with their severity, the whole group of pregnant women and the multiparae group showed significant differences in scores on emotion of Skindex-29 between the presence and absence of striae gravidarum (p = 0.012 and p = 0.011). Pregnant women with severe striae gravidarum showed significantly higher scores on emotion of Skindex-29 compared with those with absent or mild striae gravidarum (p < 0.001 and p = 0.005). CONCLUSIONS: There was no difference in generic QOL of pregnant women between the presence and absence of striae gravidarum, although the occurrence and severity of striae gravidarum influenced their dermatology-specific QOL. Multiparae women were especially impaired by striae gravidarum and it is considered important to prevent or reduce the severity of striae gravidarum of the multiparae group.     

VALVE MORPHOLOGY OF SYNEDRA GOULARDI (BACILLARIOPHYCEAE)1

Specimens of Synedra goulardi Bréb. from samples taken in Costa Rica were acid cleaned and examined by light and scanning electron microscopy. This linear-lanceolate diatom displays an unusual pattern of markings in its central area which have been mistaken as striae but are actually internal costae. As is typical for members of its genus and that of many other genera in the Fragilariaceae, S. goulardi possesses non-stalked labiate processes, apical pore fields and a lack of marginal spines. There is a great deal of variability in the striae of the genus, ranging from single rows of puncta to areolate striae. Synedra goulardi has double punctate striae. The presence of fossil forms (Neogene) with single punctate striae suggest this may be a primitive condition in the genus.     

De novo sterologenesis in the skin. II. Regulation by cutaneous barrier requirements

Recent studies suggest: that the epidermis and pilosebaceous epithelium are important sites of de novo sterol synthesis, and that the rate of cutaneous cholesterol synthesis does not change with alterations in circulating sterol levels. Since cutaneous sterols may be important for permeability barrier function, we studied the effect of experimentally altered barrier function on de novo sterologenesis in the epidermal and dermal layers of the skin. Epidermal sterologenesis appeared to be modulated by the skin's barrier requirements because topical detergent and acetone treatment stimulated de novo synthesis of nonsaponifiable lipids in the epidermis, but not in the dermis. Synthetic activity paralleled both the return of barrier function toward normal and the extent of prior damage to the barrier. Moreover, plastic-wrap occlusion of solvent-treated sites simultaneously corrected both the barrier abnormality and normalized sterol synthesis, further linking increased epidermal sterologenesis to barrier requirements. Whereas topical applications of a variety of other topical lipids did not down-regulate synthesis, epicutaneously applied 25-hydroxycholesterol appeared to diminish synthesis. These results suggest that maintenance of barrier function is one purpose of epidermal de novo nonsaponifiable lipid synthesis, and demonstrate further that, despite a lack of low density lipoprotein receptors, epidermis can regulate its lipid-synthetic apparatus in response to certain specific requirements.     

Effects of cardiotonic steroids on dermal collagen synthesis and wound healing.

We previously reported that cardiotonic steroids stimulate collagen synthesis by cardiac fibroblasts in a process that involves signaling through the Na-K-ATPase pathway (Elkareh et al. Hypertension 49: 215-224, 2007). In this study, we examined the effect of cardiotonic steroids on dermal fibroblasts collagen synthesis and on wound healing. Increased collagen expression by human dermal fibroblasts was noted in response to the cardiotonic steroid marinobufagenin in a dose- and time-dependent fashion. An eightfold increase in collagen synthesis was noted when cells were exposed to 10 nM marinobufagenin for 24 h (P < 0.01). Similar increases in proline incorporation were seen following treatment with digoxin, ouabain, and marinobufagenin (10 nM x 24 h, all results P < 0.01 vs. control). The coadministration of the Src inhibitor PP2 or N-acetylcysteine completely prevented collagen stimulation by marinobufagenin. Next, we examined the effect of digoxin, ouabain, and marinobufagenin on the rate of wound closure in an in vitro model where human dermal fibroblasts cultures were wounded with a pipette tip and monitored by digital microscopy. Finally, we administered digoxin in an in vivo wound healing model. Olive oil was chosen as the digoxin carrier because of a favorable partition coefficient observed for labeled digoxin with saline. This application significantly accelerated in vivo wound healing in rats wounded with an 8-mm biopsy cut. Increased collagen accumulation was noted 9 days after wounding (both P < 0.01). The data suggest that cardiotonic steroids induce increases in collagen synthesis by dermal fibroblasts, as could potentially be exploited to accelerate wound healing.     

A novel organogermanium protected atopic dermatitis induced by oxazolone

Atopic dermatitis (AD) is a chronic inflammatory disease of the skin that is often associated with other atopic diseases, such as asthma and allergic rhinitis. Although topical steroids have widely been prescribed for patients with AD, skin abnormalities are frequently observed after prolonged steroid treatment. In this study, a novel water-soluble organogermanium compound (Ge-Vit) was prepared because organogermanium is a known INF-γ inducer. The Ge-Vit treatment decreased the basal TEWL and IgE production and attenuated the disruption of the skin barrier function in a murine model of chronic contact dermatitis. The histological examination further supported the anti-AD activities. These results suggested that Ge-Vit can be a useful drug candidate for treating atopic dermatitis.     

Topical application of a selective cyclooxygenase inhibitor suppresses UVB mediated cutaneous inflammation

Ultraviolet B (UVB) radiation causes much of the cutaneous damage after both acute and long-term exposure, and is also the most important etiologic agent in human skin cancer. UVB exposure initially induces an inflammatory response characterized by edema, dermal infiltration of leukocytes, sunburn cell formation, as well as the induction of cyclooxygenase-2 (COX-2) gene expression and subsequent increase in the production and release of prostaglandins. This process of inflammation induced by UVB exposure has been linked to tumor formation. Recently, a specific COX-2 inhibitor, Celecoxib, was developed, which inhibits COX-2-induced inflammation without inhibiting the cytoprotective function of cyclooxygenase-1 (COX-1). The present study compared the effects of topical treatment with Celecoxib (a specific COX-2 inhibitor) and Ibuprofen (a nonspecific COX inhibitor) on the acute UVB-induced cutaneous inflammatory response. We show that the specific inhibition of COX-2 effectively reduced many parameters of UVB-mediated inflammation, including edema, dermal neutrophil infiltration and activation, prostaglandin E2 (PGE2) levels and the formation of sunburn cells. By inhibiting this inflammatory response, topical Celecoxib treatment may ultimately be effective in preventing UVB-induced tumor development in the skin.     

Striae albae: a morphological study on the human skin

Specimens of abdomen skin, comprising alternate areas of striae albae and healthy skin, were removed during surgical lipectomy from multiparous and obese women between the ages of 24 and 53 years. A flattening and thinning of the striae albae surface and the almost complete disappearance of dermal papillae was observed in paraffin and thin sections. The papillary dermis was found to be almost completely replaced by straight bundles of collagen fibres running parallel to the skin surface. Immunofluorescence data revealed in these bundles high positivity for type I collagen. The underlying reticular dermis was also found to contain large densely packed bundles of collagen fibres running parallel to the skin surface. Both papillary and reticular dermis collagen fibres were mainly arranged orthogonally to the main axis of the stria. Furthermore, the density of the collagen fibre bundles and the diameter of the collagen fibrils was found to be greater than that of the clinically healthy skin. A larger number of elastic fibres, which presented an abnormal ultrastructural appearance, were visible in pathological papillary and reticular dermis.     

Long-term cerebral cortex protection and behavioral stabilization by gonadal steroid hormones after transient focal hypoxia

Sex steroids are neuroprotective following traumatic brain injury or during neurodegenerative processes. In a recent short-term study, we have shown that 17β-estradiol (E) and progesterone (P) applied directly after ischemia reduced the infarct volume by more than 70%. This protection might primarily result from the anti-inflammatory effects of steroids. Here, we focus on the long-term neuroprotection by both steroids with respect to the infarct volume, functional recovery, and vessel density in the penumbra. The application of E/P during the first 48h after stroke (transient middle cerebral artery occlusion, tMCAO) revealed neuroprotection after two weeks. The infarct area was reduced by 70% and motor activity was preserved compared to placebo-treated animals. Blood vessel density in the penumbra using immunohistochemistry for von Willebrand factor showed increased vessel density after tMCAO which was not affected by hormones. Expression of vascular endothelial growth factor (VEGF) and its receptor (R1) was increased at 24h after tMCAO and up-regulated by E/P but not changed 14 days after stroke. These findings suggest that the neuroprotective potency of both steroids is sustained and persists for at least two weeks. Besides anti-inflammatory and anti-apoptotic actions, angiogenesis in the damaged area appears to be initially affected early after ischemia and is manifested up to two weeks. This article is part of a Special Issue entitled 'Neurosteroids'.     

Whey Protein/Polysaccharide-Stabilized Emulsions: Effect of Polymer Type and pH on Release and Topical Delivery of Salicylic Acid

Emulsions are widely used as topical formulations in the pharmaceutical and cosmetic industries. They are thermodynamically unstable and require emulsifiers for stabilization. Studies have indicated that emulsifiers could affect topical delivery of actives, and this study was therefore designed to investigate the effects of different polymers, applied as emulsifiers, as well as the effects of pH on the release and topical delivery of the active. O/w emulsions were prepared by the layer-by-layer technique, with whey protein forming the first layer around the oil droplets, while either chitosan or carrageenan was subsequently adsorbed to the protein at the interface. Additionally, the emulsions were prepared at three different pH values to introduce different charges to the polymers. The active ingredient, salicylic acid, was incorporated into the oil phase of the emulsions. Physical characterization of the resulting formulations, i.e., droplet size, zeta potential, stability, and turbidity in the water phase, was performed. Release studies were conducted, after which skin absorption studies were performed on the five most stable emulsions, by using Franz type diffusion cells and utilizing human, abdominal skin membranes. It was found that an increase in emulsion droplet charge could negatively affect the release of salicylic acid from these formulations. Contrary, positively charged emulsion droplets were found to enhance dermal and transdermal delivery of salicylic acid from emulsions. It was hypothesized that electrostatic complex formation between the emulsifier and salicylic acid could affect its release, whereas electrostatic interaction between the emulsion droplets and skin could influence dermal/transdermal delivery of the active.     

In vitro toxicity testing for antibacterials against human keratinocytes

The use of cultured human keratinocytes in an in vitro comparison of topical antibacterial toxicity for epithelial cells was examined. The complement of three assessments allows testing of epithelial migration, growth, and survival. The three assessments included (1) flow cytometry for determination of cell survival, (2) a comparison of confluent cell culture growth after antibacterial exposures, and (3) an evaluation of cell migration using a technique of dermal explants to study radial migration. A comparative ranking of the toxicities of the various topical antibacterials was determined with the three assessments. This has confirmed anecdotal reports that many of the topical antibacterials are cell-toxic and may inhibit wound healing. This information can be directly extrapolated to the clinical setting, unlike many of the animal data for wound healing that currently exist.     

The structure of the cuticular plate, an in vivo actin gel

The cuticular plate is a network of actin filaments found in hair cells of the cochlea. In the alligator lizard, it consists of rootlets, emanating from the stereocilia, and of cross-connecting actin filaments that anchor these rootlets. In thin sections, this network displays striking patches of 650 +/- 110-A striae. By quantitative analyses of the images, the mystery of the striae can be explained. They are due in part to the rootlets which are sets of flat ribbons of actin filaments. The ribbons in each set are separated by approximately 650 A. Numerous whiskers 30 A in diameter extend from each ribbon's face, interconnecting adjacent ribbons. The nonrootlet filaments, except at the margins of the cell, occur primarily as single filaments. Like the ribbons, they are bristling with whiskers. The patches of striae are explained by ribbons and filaments held at a 650-A separation by the whiskers that project from them. A simple model for regions of bewhiskered filaments is a box crammed full of randomly oriented test- tube brushes. A thin slice through the box will show regions of dark lines or striae due to the wire backbones of the brushes separated from one another by the bristle length. Using the computer instead of test- tube brushes, we have been able to model quantitatively the filament distribution and pattern of striae seen in the cuticular plate of the lizard. The organization of actin filaments we have deduced from our simulations differs from that found in macrophages or in the terminal web of intestinal epithelial cells.     

Neuropsychopharmacological properties of neuroactive steroids.

In addition to the well-known genomic effects of steroid molecules via intracellular steroid receptors, certain steroids rapidly alter neuronal excitability through interaction with neurotransmitter-gated ion channels. Several of these steroids accumulate in the brain after local synthesis or after metabolism of adrenal steroids. The 3alpha-hydroxy ring A-reduced pregnane steroids allopregnanolone and tetrahydrodeoxycorticosterone have been thought not to interact with intracellular receptors, but enhance gamma-aminobutyric acid (GABA)-mediated chloride currents, whereas pregnenolone sulfate and dehydroepiandrosterone (DHEA) sulfate display functional antagonistic properties at GABA(A) receptors. We demonstrated that these neuroactive steroids can regulate also gene expression via the progesterone receptor after intracellular oxidation. Thus, in physiological concentrations these neuroactive steroids regulate neuronal function through their concurrent influence on transmitter-gated ion channels and gene expression. When administered in animal studies, memory-enhancing effects have been shown for pregnenolone sulfate and DHEA. The 3alpha-hydroxy ring A-reduced neuroactive steroids predominantly display anxiolytic, anticonvulsant, and hypnotic activities. Sleep studies evaluating the effects of progesterone as a precursor molecule for these neuroactive steroids revealed a sleep electroencephalogram pattern similar to that obtained by the administration of benzodiazepines. These findings extend the concept of a "cross-talk" between membrane and nuclear hormone effects and provide a new role for the therapeutic application of these steroids in neurology and psychiatry.     

脱细胞真皮基质治疗对糖尿病足综合征合并下肢动脉硬化闭塞患者神经病变和对足部功能的影响

目的:探究脱细胞真皮基质治疗对糖尿病足综合征合并下肢动脉硬化闭塞患者神经病变的缓解作用和对足部功能的影响。方法:选择本院2017.5-2020.5收治的80例糖尿病足综合征合并下肢动脉硬化闭塞患者平均分为观察组和对照组2组,其中对照组患者给与常规干预结合下肢动脉腔内治疗,观察组则在对照组的基础上实施脱细胞真皮基质治疗。分析两组患者治疗前后TCSS评分、神经传导速度、足部功能、治疗效果、创面感染发生率、治疗费用以及并发症发生率的差异。结果:治疗后观察组患者TCSS评分和足部功能评分均较对照组低,神经传导速度较对照组快,差异有统计学意义(P<0.05);观察组患者治疗总有效率、患者创面感染发生率和并发症发生率分别为100.00%、2.50%和2.50%,对照组患者则分别为80.00%、17.50%和55.00%,且对照组住院费用较观察组高,差异有统计学意义(P<0.05)。结论:脱细胞真皮基质治疗对糖尿病足综合征合并下肢动脉硬化闭塞患者神经病变具有确切的缓解作用,尤其对足部功能效果显著,值得临床广泛推广使用。