Different types of emollient cream exhibit diverse physiological effects on the skin barrier in adults with atopic dermatitis.

BACKGROUND: Eczema (atopic dermatitis; AD) is a very common itchy skin condition affecting 1 in 5 children and up to 1 in 10 adults worldwide. The skin of eczema sufferers is prone to redness, irritation and dryness because it does not form an effective barrier, i.e. the ability of the skin to stop irritants, allergens and microorganisms getting into the body. Skin barrier dysfunction is a hallmark of AD. The regular and liberal (600 g/week for an adult) use of emollients is recommended for all patients with eczema), even between episodes of itching and redness, to soften and soothe the skin. In England alone, almost 9 million prescriptions for emollient creams were issued in 2018, at a cost of over £50 million. Despite this widespread use, relatively little is known about how commonly prescribed emollient creams affect the skin's barrier, and thus the role of moisturizers in AD development and progression remains unclear. We set out to compare three different types of emollient cream and a no-treatment control. AIM: To compare the barrier-strengthening properties of a new moisturizer containing urea and glycerol (urea-glycerol cream; UGC), with those of a glycerol-containing moisturizer (glycerol cream; GC), a simple paraffin cream (PC) with no humectant, and a no-treatment control (NTC). METHODS: This was an observer-blinded prospective Phase 2 within-subject multilateral single-centre randomized controlled trial in adults with AD (Clinical Trials #NCT03901144). The intervention involved 4 weeks of treatment, twice daily, with the three products applied to one of four areas on the forearms the (the fourth area was the untreated control, randomized allocation). Skin properties [dryness, transepidermal water loss (TEWL), hydration and natural moisturizing factor (NMF) levels] were assessed before, during and after treatment to see what happened to the skin's barrier. The primary outcome was skin sensitivity to the irritant sodium lauryl sulfate (SLS) after treatment. We performed tests on the skin before and after treatment to see what happened to the skin's barrier. RESULTS: In total, 49 patients were randomized, completed treatment and included in the analysis. UGC significantly reduced the response to SLS as indicated by a reduction in TEWL compared with NTC (-9.0 g/m2 /h; 95% CI -12.56 to -5.49), with PC (-9.0 g/m2 /h; 95% CI -12.60 to -5.44) and with GC -4.2 g/m2 /h; 95% CI 7.76 to -0.63). Skin moisturization improved at sites treated with UGC compared with NTC and PC, and this was accompanied by concordant changes in dryness and NMF levels. Subgroup analysis suggested FLG-dependent enhancement of treatment effects. CONCLUSION: The study showed that not all emollient creams for eczema are equal. The simple paraffin-based emollient, which represents the most widely prescribed type of emollient cream in England, had no effect on the skin's barrier and reduced the skin's NMF. UGC markedly improved the skin's barrier and protected against irritation. GC performed better than PC, but not as well as UGC. UGC strengthened the skin barrier through a mechanism involving increased NMF levels in the skin, and imparted protection from SLS-induced irritation. By helping correct a major pathophysiological process, UGC has the potential to improve the long-term control of AD. The results show that different emollient creams have different effects on our skin, and only certain types have the ability to improve the skin's barrier and protect against irritants that trigger eczema.

Liposome-mediated delivery of challenging chemicals to aid environmental assessment of Bioaccumulative (B) and Toxic (T) properties.

Standard aquatic toxicity tests of chemicals are often limited by the chemicals' water solubility. Liposomes have been widely used in the pharmaceutical industry to overcome poor pharmacokinetics and biodistribution. In this work, liposomes were synthesized and used in an ecotoxicological context, as a tool to assure stable dosing of technically challenging chemicals to zooplankton. Three chemicals with distinctly different characteristics were successfully incorporated into the liposomes: Tetrabromobisphenol A (TBBPA, log Kow 5.9, pKa1 7.5, pKa2 8.5), chlorinated paraffin CP-52 (log Kow 8-12) and perfluorooctanoic acid (PFOA, pKa 2.8). The size, production yield and stability over time was similar for all blank and chemical-loaded liposomes, except for when the liposomes were loaded with 10 or 100 mg g-1 PFOA. PFOA increased the size and decreased the production yield and stability of the liposomes. Daphnia magna were exposed to blank and chemical-loaded liposomes in 48 hour incubation experiments. A dose-dependent increase in body burden in D. magna and increased immobilization (LD50 = 7.6 ng CPs per individual) was observed. This confirms not only the ingestion of the liposomes but also the successful internalization of chemicals. This study shows that liposomes can be a reliable alternative to aid the study of aquatic toxicity of challenging chemicals.

Antimicrobial emulsions: Formulation of a triggered release reactive oxygen delivery system.

The enzyme glucose oxidase mediates the oxidation of glucose to produce reactive oxygen species (ROS), such as hydrogen peroxide. This reaction and its products are key to providing honey with its antimicrobial properties. Currently, honey is an adherent, highly viscous product that produces ROS by means of a water-initiated reaction. These properties reduce clinical usability and present a formulation problem for long term stability. This study aims to engineer a water-in-oil emulsion containing an engineered honey (SurgihoneyRO™) that is easy to administer topically and is controllably activated in-situ. Paraffin oil continuous emulsions formulated using the emulsifier polyglycerol polyricinoleate displayed shear-thinning characteristics. Viscosities between 1.4 and 19.3 Pa·s were achieved at a shear rate representative of post-mixing conditions (4.1 s-1) by changing the volume of the dispersed phase (30-60%). Notably, this wide viscosity range will be useful in tailoring future formulations for specific application mechanisms. When exposed to water and shear, these emulsion systems were found to undergo catastrophic phase inversion, evidenced by a change in conductivity from 0 µS in the non-aqueous state, to >180 µS in the sheared, inverted state. Encouragingly, sheared formulations containing ≥50% SurgihoneyRO™ generated sufficient levels of ROS to inhibit growth of clinically relevant Gram-positive and Gram-negative bacteria. This study demonstrates an ability to formulate ROS producing emulsions for use as an alternative to current topical antibiotic-based treatments. Promisingly, the ability of this system to release water-sensitive actives in response to shear may be useful for controlled delivery of other therapeutic molecules.

Diagnostic accuracy of a new ex vivo confocal laser scanning microscope compared to H&E-stained paraffin slides for micrographic surgery of basal cell carcinoma.

BACKGROUND: For safe excision of malignant skin tumours, complete negative surgical margins are mandatory. The gold standard for analysis is frozen sections or paraffin-embedded haematoxylin and eosin (H&E)-stained slides. The production of H&E-stained slides is time-consuming (>20 h) while wounds remain unclosed. An upcoming method is confocal laser scanning microscopy (CLSM), a technique that scans unfixed fresh tissue rapidly. OBJECTIVE: Evaluation of the process to generate and analyse CLSM images and assessment of the accuracy to detect basal cell carcinoma (BCC) tissue. METHODS: Digital microscopic images were generated by the Histolog Scanner v1 from 544 fresh specimens of 148 BCCs that had been stained with a 0.01% proflavine solution. CLSM images were compared to the histological diagnoses of the corresponding H&E-stained slides. RESULTS: A total of 525 images could be analysed. The sensitivity was 73% (95% CI = [65.27%; 80.47%]), and the specificity was 96% (95% CI = [93.40%; 97.60%]). Detection of BCCs in punch biopsies was certainly detected (sensitivity of 100%). The median total time to generate and evaluate a CLSM image was 5.17 min (maximum 20.17 min and minimum 2.05 min). The greatest challenge was flattening the specimen to assure complete representation of the surgical margins. CONCLUSION: Confocal laser scanning microscopy is a time-saving and very effective alternative to classical paraffin-embedded or frozen sections. Patient treatment could be improved due to shorter hospital stays or faster outpatient therapy due to reduced intervals between surgical stages. Diagnostic accuracy of the microscope used still must be improved.

Stimulated and unstimulated saliva samples have significantly different bacterial profiles.

Epidemiological studies use saliva on a regular basis as a non-invasive and easy-to-take sample, which is assumed to be a microbial representative of the oral cavity ecosystem. However, comparative studies between different kinds of saliva samples normally used in microbial studies are scarce. The aim of the current study was to compare oral microbiota composition between two different saliva samples collected simultaneously: non-stimulated saliva with paper points and stimulated saliva collected after chewing paraffin gum. DNA was extracted from saliva samples of ten individuals, then analyzed by 16S rRNA pyrosequencing to describe bacterial diversity. The results demonstrate significant differences between the microbiota of these two kinds of saliva. Stimulated saliva was found to contain an estimated number of species over three times higher than unstimulated saliva. In addition, bacterial composition at the class and genus level was radically different between both types of samples. When compared to other oral niches, both types of saliva showed some similarity to tongue and buccal mucosa, but they do not correlate at all with the bacterial composition described in supra- or sub-gingival dental plaque, questioning their use in etiological and epidemiological studies of oral diseases of microbial origin.

Infinium DNA Methylation Microarrays on Formalin-Fixed, Paraffin-Embedded Samples.

Formalin-fixed, paraffin-embedded (FFPE) samples usually yield fragmented DNA, which is incompatible with traditional Infinium Methylation beadchips. In this chapter, we aim to explain in detail all the processes carried out in order to obtain high-quality methylation profiles from FFPE samples through an FFPE restoration procedure. High-throughput methylation profiling platforms such as the Infinium Methylation beadchips have been extensively used by the scientific community to elucidate many hypotheses in multiple scenarios, now with the incorporation of FFPE samples to these platforms, a myriad of new opportunities is being opened.

Oil Perception-Detection Thresholds for Varying Fatty Stimuli and Inter-individual Differences.

Multiple lines of research have demonstrated that humans can perceive fat in the form of free fatty acids (FFAs). However, the dietary concentration of FFAs is generally very low and fat is mainly consumed as triacylglycerol (TAG). The aim of this study was to examine the perception of different fatty stimuli and possible associations between them. Therefore, detection thresholds for 4 fatty stimuli (oleic acid [FFA], paraffin oil [mixture of hydrocarbon molecules], canola oil [TAG-rich], and canola oil spiked with oleic acid [rich in TAGs and FFAs]) were determined in 30 healthy participants. Additionally, inter-individual differences in fat perception were examined. It was observed that oleic acid was perceivable at significantly lower concentrations than all other stimuli (P < 0.001). Similarly, canola oil with oleic acid was detectable at lower concentrations than canola oil alone (P < 0.001). Moreover, canola oil detection thresholds were significantly lower than paraffin oil detection thresholds (P = 0.017). Participants who were sensitive for low concentrations for oleic acid showed lower detection thresholds for canola oil with and without oleic acid, compared with participants that were less sensitive for oleic acid. The results of this study demonstrate that the higher the concentrations of FFAs in the stimuli, the lower the individual fat detection threshold. Moreover, participants being sensitive for lower concentrations of FFAs are also more likely to detect low concentrations of TAG-rich fats as it is found in the human diet.

In vivo confocal Raman microscopic determination of depth profiles of the stratum corneum lipid organization influenced by application of various oils.

BACKGROUND: The intercellular lipids (ICL) of stratum corneum (SC) play an important role in maintaining the skin barrier function. The lateral and lamellar packing order of ICL in SC is not homogenous, but rather depth-dependent. OBJECTIVE: This study aimed to analyze the influence of the topically applied mineral-derived (paraffin and petrolatum) and plant-derived (almond oil and jojoba oil) oils on the depth-dependent ICL profile ordering of the SC in vivo. METHOD: Confocal Raman microscopy (CRM), a unique tool to analyze the depth profile of the ICL structure non-invasively, is employed to investigate the interaction between oils and human SC in vivo. RESULTS: The results show that the response of SC to oils' permeation varies in the depths. All oils remain in the upper layers of the SC (0-20% of SC thickness) and show predominated differences of ICL ordering from intact skin. In these depths, skin treated with plant-derived oils shows more disordered lateral and lamellar packing order of ICL than intact skin (p<0.05). In the intermediate layers of SC (30-50% of SC thickness), the oils do not influence the lateral packing order of SC ICL (p>0.1), except plant-derived oils at the depth 30% of SC thickness. In the deeper layers of the SC (60-100% of SC thickness), no difference between ICL lateral packing order of the oil-treated and intact skin can be observed, except that at the depths of 70-90% of the SC thickness, where slight changes with more disorder states are measured for plant-derived oil treated skin (p<0.1), which could be explained by the penetration of free fatty acid fractions in the deep-located SC areas. CONCLUSION: Both oil types remain in the superficial layers of the SC (0-20% of the SC thickness). Skin treated with mineral- and plant-derived oils shows significantly higher disordered lateral and lamellar packing order of ICL in these layers of the SC compared to intact skin. Plant-derived oils significantly changed the ICL ordering in the depths of 30% and 70-90% of the SC thickness, which is likely due to the penetration of free fatty acids in the deeper layers of the SC.

Wear behaviour of UHMWPE reinforced by carbon nanofiller and paraffin oil for joint replacement.

The majority of artificial joints incorporate biomedical grade Ultra High Molecular Weight Poly Ethylene (UHMWPE), whose wear is considered most important in controlling service time of the whole joint. The aim of this work was to improve wear resistance of UHMWPE through the addition of 0.5-2.0wt% of Carbon Nano Filler (CNF) and 2% wt of Paraffin Oil (PO) using ball milling (BM) and extrusion techniques (EX). The wear tests on these nanocomposites were conducted by a pin on disc in dry (air) and wet media (simulated synovial fluid or artificial lubricant, and bovine synovial fluid or natural lubricant). Mechanical tests (tensile and hardness), physical analysis (calorimetric, density, wet ability, roughness) and morphological observations were also performed. The experimental results showed that natural lubricant provides the greatest reduction in wear rate while the largest one occurred in air. Furthermore, the BM mixed nanocomposites with a filler load of 1.0% exhibited the best wear resistance among all the samples with an improvement of 42%, 64% and 83% in air, artificial and natural lubricant, respectively. This is due to its higher ductility and thermal features, and lower wet ability in the two lubricants.

Effects of Carriers, Emulsifiers, and Biopesticides for Direct Silk Treatments on Caterpillar Feeding Damage and Ear Development in Sweet Corn.

In the northeastern United States, control of Lepidopteran pests of sweet corn, particularly corn earworm [Helicoverpa zea (Boddie)], is difficult using organic methods. The direct application of corn oil and Bacillus thuringiensis (Bt) to corn silk has been shown to reduce ear damage from corn earworm in past studies; these studies sought to optimize this method by evaluating additional carrier and biopesticide mixtures that comply with the United States Federal Insecticide, Fungicide, and Rodenticide Act and National Organic Standards. Carriers, which are liquids used to dissolve the biopesticide and deliver it into the tip of the ear, may have phytotoxic or insecticidal properties. Experiments conducted from 2001 to 2005 evaluated caterpillar damage and ear development effects from carriers (vegetable and paraffinic oils and carrageenan), biopesticides (Bt, spinsosad, and neem), and three emulsifiers in various combinations when applied directly to the tips of the ears 5-7 d after silk initiation. There were no effects of emulsifiers on ear quality, except for slight reduction in caterpillar damage in one of the two years. There were no differences among corn, soy, canola, and safflower oils in corn earworm control or tip development. The carrageenan carrier had the least effect upon ear development as measured by the length of nonpollinated kernels at the tip, compared to corn oil or paraffinic oil (JMS Stylet Oil), which caused the greatest tip damage as well as an oily discoloration. The carrier-pesticide combinations with the best ear quality overall were spinosad in carrageenan or corn oil, and Bt in carrageenan.

Dioxin-like activities, halogenated flame retardants, organophosphate esters and chlorinated paraffins in dust from Australia, the United Kingdom, Canada, Sweden and China.

The concentrations of organic flame retardants (FRs) and dioxin-like activities in dust collected from five countries were investigated. The correlations between the concentrations of the different groups of FRs and dioxin-like activities were examined. Chlorinated paraffins (CPs, C9 to C31) were found in the highest concentration (median ∑CP 700 µg/g, range 280-4750 µg/g), followed by organophosphate esters (median ∑13OPEs 56 µg/g, range 21-110 µg/g), halogenated flame retardants (median ∑17HFRs 3.3 µg/g, range 0.87-14 µg/g) and polybrominated diphenyl ethers (median ∑17PBDEs 2.8 µg/g, range 0.46-11 µg/g). There were no significant differences in concentrations of the FRs among the countries but differences in PBDE and CP congener profiles were found. BDE209 predominated in dust from Australia, the UK, Sweden and China, ranging from 50 to 70% of total PBDEs. The lowest percentage of BDE209 was found in the dust from Canada, representing only 20% of total PBDEs. For CPs in dust from Sweden, the long-chain CPs (especially C18 congeners) predominated, while for other countries, medium-chain CPs (especially C14 congeners) predominated. The dioxin-activities of the dusts ranged from 58 to 590 pg CALUX-TEQ/g, and had a median of 200 pg CALUX-TEQ/g. There were significant positive correlations between concentrations of PBDEs and CPs with dioxin-like activities. The dioxin-like activity may be due to the presence of polychlorinated or polybrominated dioxin/furans (PBDD/DFs) or polychlorinated naphthalenes (PCNs) in the dust. The PBDD/DFs are known impurities and degradation product of the penta-BDE mixture, and PCNs are known impurities of CPs which exhibit dioxin-like activities.

Interaction of low dose of fish oil and glucocorticoids on insulin sensitivity and lipolysis in healthy humans: A randomized controlled study.

SCOPE: This study examined the interaction of fish oil (FO) with dexamethasone on glucose and lipid metabolisms in healthy subjects. METHODS AND RESULTS: The study included two consecutive parts. Part A (randomized) in 16 subjects studied the effects of dexamethasone (2 days, 2 mg/day) versus placebo (lactose), part B (two parallel subgroups of eight) studied the interaction of FO (3 wk, 840 mg/day of EPA + DHA) with dexamethasone. Insulin sensitivity of lipolysis (d5-glycerol infusion + microdialysis), endogenous glucose production, and muscle glucose uptake were assessed by a three-step hot insulin clamp and substrate oxidation by indirect calorimetry. Dexamethasone induced liver and peripheral insulin resistance, an increase in fat oxidation, and a decrease in suppression of plasma nonesterified fatty acids (NEFAs). FO amplified the effects of dexamethasone by increasing liver and muscle insulin resistance, by reducing suppression of plasma NEFAs and fat oxidation and by increasing adipose tissue (AT) lipolysis. CONCLUSION: FO, given at a moderate dose in healthy subjects prior to a very short-term (2 days) low dose of a synthetic glucocorticoid, worsened its deleterious effects on insulin sensitivity. The enhancing effect of FO on fat oxidation and AT lipolysis might be a protective effect toward an increase in fat mass.

A new ovitrap made of slow release natural materials containing pyriproxyfen for Aedes aegypti (Diptera:Culicidae) control.

ABSTRACT This initial study is aimed to measure the performance of incorporating pyriproxyfen in natural materials with low environmental impact to obtain slow release formulations that can be used as larvicidal or autocidal ovitraps avoiding hatched Aedes aegypti (L.) eggs to emerge as adults. Hollow candles made of beeswax or paraffin:stearin 1:1 mixture containing pyriproxyfen 0.01 and 0.05% were prepared and used as holding water containers for larval bioassay. Pyriproxyfen was released quickly into the larvae-breeding water. Ae. aegypti larvae were introduced immediately after the addition of tap water to the hollow candles (t = 1 min) or after 1, 4, and 8 h. More than 40% of the larvae did not emerge as adults for t = 1 min, reaching 80-100% when the larvae were added after 1 or 4 h, respectively. The hollow candles were kept at room temperature, and water was replaced every 15 d. Bioassays performed every 30 d showed that the residual activity obtained for both matrices and both concentrations of pyriproxyfen was higher than 360 d, with 100% inhibition of adult emergence.

Time-dependent morphological and biochemical changes following cutaneous thermal burn injury and their modulation by copper nicotinate complex: an animal model.

BACKGROUND: Thermal tissue injury is partly mediated by reactive oxygen metabolites. Oxygen free radicals are contributory to local tissue damage following thermal injury and accordingly an interventional therapy using antioxidants may be beneficial. Copper nicotinate complex can scavenge reactive oxygen species (i.e., has antioxidant activity). OBJECTIVES: To examine time-related morphological and biochemical changes following skin thermal injury and their modulation by copper nicotinate complex. MATERIALS AND METHODS: An animal model composed of 80 albino rats was established. Ten rats (nonburn group) served as a control group. Seventy rats (burn group) were anesthetized, given a 10% total body surface area, full-thickness burn. Ten rats (from the postburn group) were sacrificed after 24 h (without treatment, i.e., untreated-burn group). The remaining rats were divided into three subgroups (20 rats, each) and were treated topically either with soft paraffin, moist exposed burn ointment (MEBO, a standard therapeutic treatment for burns), or copper nicotinate complex. Five animals from each subgroup were sacrificed every week over a period of 4 weeks. The morphological and biochemical changes were evaluated and compared among the different groups. RESULTS: High levels of the plasma and skin nitiric oxide (marker of oxidative stress) were observed in the untreated-burn group. These levels were significantly low following the application of copper nicotinate complex. Low levels of plasma and skin superoxide dismutase (marker of oxidative stress) and plasma ceruloplasmin were observed in the untreated-burn group. These levels were significantly high following copper nicotinate complex treatment. The total and differential leukocyte counts were low following the onset of the thermal injury. They gradually returned to normal levels over a 4-week period following the application of MEBO or copper nicotinate complex. Compared to untreated-burn group, postburn-healing changes (resolution of the inflammatory reaction, reepithelization of the epidermis, angiogenesis, deposition of collagen fibers, and recovery of the subcellualr organelles) were significantly accelerated following the application of either MEBO or copper nicotinate complex. CONCLUSIONS: Application of copper nicotinate complex was associated with improved healing of the thermal burns of the skin. The underlying molecular changes underlying these effects await further investigations.

In vivo investigations on the penetration of various oils and their influence on the skin barrier.

BACKGROUND: The skin represents a potent barrier to the environment, which can be enhanced by the topical application of skin care products, such as oil and oil-based formulations by moisturizing the skin. METHODS: The aim of this study was the investigation of the penetration behaviour of four vegetable oils and of paraffin oil into the stratum corneum by laser scanning microscopy. In addition, the occlusion capacity of these substances was assessed by transepidermal water loss (TEWL) measurements. Petrolatum served as a positive control for skin occlusion. The study was conducted in vivo and included six healthy volunteers. RESULTS: Paraffin oil, as well as the vegetable oils, penetrated only into the first upper layers of the stratum corneum. TEWL measurements indicated that the application of the vegetable oils (except jojoba oil) as well as paraffin oil, led to a similar occlusion of the skin surface. The most effective occlusion was found for petrolatum. CONCLUSION: For the investigated oils, a deeper penetration than into the first upper layers of the stratum corneum could be excluded. The decreased TEWL values indicate that the application of the oils leads to a semi-occlusion of the skin surface as it is intended by the use of oils to retain moisture in skin.

Slow-release of methanogenic inhibitors derived from encapsulated calcium carbide using paraffin wax and/or rosin: matrix optimization and diffusion characteristics.

Acetylene has been found to significantly inhibit biological activity of methanogens and thus might be applicable for reducing the generation and emission of methane from municipal solid waste landfills. However, acetylene is gaseous and so it is considered physically infeasible to directly apply this gas to waste in landfill conditions. In the present study, a novel acetylene release mechanism was tested, using a matrix of acetylene entrapped in high hydrophobic paraffin wax and/or rosin and calcium carbide capsules with a ratio of 1.0 g g(-1) matrix and a diameter of 10 mm to facilitate the gradual release of acetylene. A diffusion mechanism model (Q = &b.gamma; × t (0.5)) for the matrix was derived based on the T. Higuchi equation, and the effective diffusion coefficients (D(e)) were acquired by linear fitting. Additionally, it was found that D(e) remained constant when the rosin content was up to more than 20% g g(-1) matrix.

CT features of foreign body granulomas after cosmetic paraffin injection into the cervicofacial area.

PURPOSE: Cosmetic injection of paraffin into cervicofacial tissues has been practiced in the past, especially in Asia, resulting in foreign body granuloma (paraffinoma). The purpose of this study was to describe the computed tomography (CT) findings of cervicofacial paraffinomas. MATERIALS AND METHODS: CT images of 5 patients (4 women and 1 man; age range, 54-80 years; mean age, 67.6 years), who had received direct paraffin injections into cervicofacial tissues, were reviewed retrospectively. RESULTS: The lesions were bilateral and located in the subcutaneous fat layer of the cheek (n = 5), buccal space (n = 2), periorbital area (n = 1), periauricular area (n = 1), neck (n = 1), and nose (n = 1). The predominant CT features were speckled mass formation (n = 3), fat-density nodule (n = 5), high-density nodule (n = 5), nodular calcification (n = 5), and rim calcification (n = 4). CONCLUSION: Paraffinomas in the cervicofacial region have specific CT features that are distinct from other soft tissue masses.

Blood constituents trigger brain swelling, tissue death, and reduction of glucose metabolism early after acute subdural hematoma in rats.

Outcome from acute subdural hematoma is often worse than would be expected from the pure increase of intracranial volume by bleeding. The aim was to test whether volume-independent pathomechanisms aggravate damage by comparing the effects of blood infusion with those of an inert fluid, paraffin oil, on intracranial pressure (ICP), cerebral perfusion pressure (CPP), local cerebral blood flow (CBF), edema formation, glucose metabolism ([18F]-deoxyglucose, MicroPET ), and histological outcome. Rats were injured by subdural infusion of 300 muL venous blood or paraffin. ICP, CPP, and CBF changes, assessed during the first 30 mins after injury, were not different between the injury groups at most time points (n=8 per group). Already at 2 h after injury, blood caused a significantly more pronounced decrease in glucose metabolism in the injured cortex when compared with paraffin (P<0.001, n=5 per group). Ipsilateral brain edema did not differ between groups at 2 h, but was significantly more pronounced in the blood-treated groups at 24 and 48 h after injury (n=8 per group). These changes caused a 56.2% larger lesion after blood when compared with paraffin (48.1+/-23.0 versus 21.1+/-11.8 mm(3); P<0.02). Blood constituent-triggered pathomechanisms aggravate the immediate effects due to ICP, CPP, and CBF during hemorrhage and lead to early reduction of glucose metabolism followed by more severe edema and histological damage.

Effects of oil on internal gas transport, radial oxygen loss, gas films and bud growth in Phragmites australis.

BACKGROUND AND AIMS: Oil pollution of wetlands is a world-wide problem but, to date, research has concentrated on its influences on salt marsh rather than freshwater plant communities. The effects of water-borne light oils (liquid paraffin and diesel) were investigated on the fresh/brackish wetland species Phragmites australis in terms of routes of oil infiltration, internal gas transport, radial O(2) loss (ROL), underwater gas films and bud growth. METHODS: Pressure flow resistances of pith cavities of nodes and aerenchyma of leaf sheaths, with or without previous exposure to oil, were recorded from flow rates under applied pressure. Convective flows were measured from living excised culms with oiled and non-oiled nodes and leaf sheaths. The effect of oil around culm basal nodes on ROL from rhizome and root apices was measured polarographically. Surface gas films on submerged shoots with and without oil treatment were recorded photographically. Growth and emergence of buds through water with and without an oil film were measured. KEY RESULTS: Internodes are virtually impermeable, but nodes of senesced and living culms are permeable to oils which can block pith cavity diaphragms, preventing flows at applied pressures of 1 kPa, natural convective transport to the rhizome, and greatly decreasing ROL to phyllospheres and rhizospheres. Oil infiltrating or covering living leaf sheaths prevents humidity-induced convection. Oil displaces surface gas films from laminae and leaf sheaths. Buds emerge only a few centimetres through oil and die. CONCLUSIONS: Oil infiltrates the gas space system via nodal and leaf sheath stomata, reducing O(2) diffusion and convective flows into the rhizome system and decreasing oxygenation of phyllospheres and rhizospheres; underwater gas exchange via gas films will be impeded. Plants can be weakened by oil-induced failure of emerging buds. Plants will be most at risk during the growing season.

Reduced pSmad2 immunodetection correlates with increased primary melanoma thickness.

Cutaneous melanoma is the most aggressive of cutaneous neoplasms. Identifying patients with an increased risk for the development of metastases is critical. This study investigates phospho-Smad2, a central factor of the transforming growth factor beta pathway, on formalin-fixed, paraffin-embedded tissues from 60 primary cutaneous melanomas (Breslow >1 mm), for its candidacy for being a prognostic marker in primary cutaneous melanoma. Phospho-Smad2 positivity was assessed for correlation with clinical parameters including Breslow index, melanoma type, survival, development of metastases, sentinel lymph node status and age. Phospho-Smad2 positivity was not associated with survival or development of metastases, suggesting that it would not be a useful prognostic marker. Despite this, we found phospho-Smad2 positivity to be correlated with low tumour thickness, indicating that as the primary tumour grows there is an increased inhibition of transforming growth factor beta signalling resulting in suppressed Smad2 phosphorylation. Additionally, phosphorylation of Smad2 in neighbouring melanoma cells and keratinocytes was interrelated, which is a further indication that Smad2 phosphorylation in primary melanoma is affected by local area microenvironmental factors. We hypothesize that the observed decrease in transforming growth factor beta signalling in thicker primary melanomas is due to the increased production of signalling inhibitors.