Photoprotection: update in UV-filter molecules, the "new wave" of sunscreens.

In this review, we provide a wide, non-comprehensive overview of the latest trends in protection against the deleterious effects of the sun. The review is divided into physical blockade of UV photons, UV photon absorption and/or reflection provided by topical sunscreens and topical antioxidant compounds. The last section is devoted to the newest generation of dietary photoprotective compounds. Possible mechanisms, particularly antioxidant, are discussed.

Differential effects of ceramide on cell viability and extracellular matrix remodeling in keratinocytes and fibroblasts.

Ceramides are used in skin care and treatment of dermatological diseases. Cell viability and extracellular matrix (ECM) remodeling are important parameters in skin health. Skin photoaging, from exposure to ultraviolet radiation, is associated with epidermal hyperplasia and dermal ECM atrophy caused by alterations in expression of matrixmetalloproteinases (MMPs), elastin and transforming growth factor-beta (TGF-beta). The purpose of this study was to determine the effects of c2-ceramide (ceramide) on the cell viability and expression of TGF-beta, MMP-1 and elastin in cultured keratinocytes and fibroblasts. Ceramide inhibited keratinocyte cell viability by apoptosis and stimulated expression of elastin, MMP-1 and TGF-beta, suggesting improved epidermal functioning by a TGF-beta mechanism. Conversely, ceramide stimulated fibroblast cell growth at the lower concentrations and inhibited the expression of MMP-1, elastin and TGF-beta, which indicates a predominantly beneficial effect in the prevention of photoaging-associated dermal alterationby TGF-beta and non-TGF-beta mechanisms. The regulation of MMP-1 expression by ceramide was transcriptionally mediated and via the activator protein-1 sequence in both keratinocytes and fibroblasts. The study delineates the specific, though differential, beneficial effects of ceramide in the prevention of epidermal hyperplasia and dermal ECM remodeling, associated with photoaging.

Molecular basis for the regenerative properties of a secretion of the mollusk Cryptomphalus aspersa.

A screen for natural products bearing pharmacological properties has yielded a secretion of the mollusk Cryptomphalus aspersa (SCA), which possesses skin-regenerative properties. In this report, we outline some of the cellular and molecular effects underlying this observation. First, we found that SCA contained antioxidant SOD and GST activities. In addition, SCA stimulated fibroblast proliferation and rearrangement of the actin cytoskeleton. Additional mechanisms involved in the regenerative effect of SCA included the stimulation of extracellular matrix assembly and the regulation of metalloproteinase activities. Together, these effects provide an array of molecular mechanisms underlying SCA-induced cellular regeneration and postulate its use in regeneration of wounded tissue.

Dietary lutein/zeaxanthin partially reduces photoaging and photocarcinogenesis in chronically UVB-irradiated Skh-1 hairless mice.

Lutein and zeaxanthin are xanthophyll carotenoids with potent antioxidant properties protecting the skin from acute photodamage. This study extended the investigation to chronic photodamage and photocarcinogenesis. Mice received either a lutein/zeaxanthin-supplemented diet or a standard nonsupplemented diet. Dorsal skin of female Skh-1 hairless mice was exposed to UVB radiation with a cumulative dose of 16,000 mJ/cm(2) for photoaging and 30,200 mJ/cm(2) for photocarcinogenesis. Clinical evaluations were performed weekly, and the animals were sacrificed 24 h after the last UVB exposure. For photoaging experiments, skin fold thickness, suprapapillary plate thickness, mast cell counts and dermal desmosine content were evaluated. For photocarcinogenesis, samples of tumors larger than 2 mm were analyzed for histological characterization, hyperproliferation index, tumor multiplicity, total tumor volume and tumor-free survival time. Results of the photoaging experiment revealed that skin fold thickness and number of infiltrating mast cells following UVB irradiation were significantly less in lutein/zeaxanthin-treated mice when compared to irradiated animals fed the standard diet. The results of the photocarcinogenesis experiment were increased tumor-free survival time, reduced tumor multiplicity and total tumor volume in lutein/zeaxanthin-treated mice in comparison with control irradiated animals fed the standard diet. These data demonstrate that dietary lutein/zeaxanthin supplementation protects the skin against UVB-induced photoaging and photocarcinogenesis.

Mathematical modelling of small wastewater treatment plants: power and limitations.

Although mathematical modelling of biological wastewater treatment processes has proved to be valuable for large-scale WWTPs (wastewater treatment plants) little experience has been acquired in the mathematical modelling of small wastewater treatment plants. This paper seeks to evaluate the applicability of mathematical modelling on small systems, which are characterized by high fluctuations in organic and hydraulic loads and little possibility for control. In order to achieve this, the paper examines the different steps in a general modelling protocol. One important bottleneck for the general use of mathematical modelling of small systems that emerges is the frequent sampling and many analyses needed for characterization of the flows while its applicability is limited. On the other hand, the determination of the model structure of a small WWTP can be quite valuable. Experiments show that tracer tests should include tests with a highly varying influent flow rate to spot independent small internal flows as these can have a significant impact on the behaviour of peak concentrations throughout the system. In addition, the model structure determination can provide useful information on dead zones, short-circuiting and mixing behaviour in the plant.

Collagen and fibronectin expression in cardiac fibroblasts from hypertensive rats.

OBJECTIVE: Left ventricular hypertrophy in spontaneously hypertensive rats (SHR) is accompanied by excessive accumulation of collagen in the myocardium. The objective of this work was to examine the role of myocardial fibroblasts in this phenomenon. METHODS: Myocardial fibroblasts from SHR and control Wistar Kyoto rats (WKY) were incubated with 14C-proline; total 14C incorporation and 14C-collagen synthesis were determined by collagenase digestion assays. 14C containing proteins were further characterised by SDS gel electrophoresis. RNA was isolated from these cultures and used for northern blot hybridisation with rodent specific cDNAs for collagen types I and III and fibronectin. RESULTS: Biosynthetic labelling of fibroblastic cell cultures with 14C-proline showed that 14C-proline incorporation into total protein expressed on a DNA basis was 30% higher in fibroblasts from hypertensive rats than in the corresponding sex and age matched normal rats. When the same set of cell cultures was examined for 14C-collagen synthesis there was a 50% increment in cell strains from hypertensive animals; these differences were highly significant. When the expression of collagen types I and III and fibronectin genes was analysed by northern blot analyses, 1.5- to 2-fold greater steady state levels of types I and III collagens and fibronectin transcripts were found in fibroblasts from hypertensive rats when compared to cells from normal rats. CONCLUSIONS: Myocardial fibroblast cultures from hypertensive rats produce increased amounts of collagen and fibronectin associated with increased expression of the genes for types I and III collagens and also for fibronectin. Myocardial fibroblasts may participate in the increased myocardial connective tissue deposition associated with genetic hypertension.

Increased collagen synthesis and increased content of type VI collagen in myocardium of tight skin mice.

OBJECTIVE: The tight skin mouse (TSK) is a mutant strain characterised by excessive collagen accumulation in skin and some internal organs such as the heart. The aims of this study were (1) to examine in vitro collagen synthesis in TSK myocardium; (2) to determine myocardial content of type VI collagen in the same model; and (3) to examine the expression of one of the genes for type VI collagen in cultured TSK myocardial fibroblasts. METHODS: Individual hearts from 8 month old heterozygous male TSK and normal sex and age matched mice were incubated with 14C proline. Total 14C protein and 14C collagen synthesis by myocardial tissues were determined with collagenase digestion and SDS gel electrophoresis. For determination of type VI collagen, hearts from 10 month old male TSK and normal mice were subjected to guanidine extraction followed by pepsin digestion, salt fractionation, and western blotting. Expression of the alpha 2(VI) collagen gene was determined in myocardial fibroblasts cultured from TSK and normal mice, employing northern and dot blot hybridizations with a murine specific cDNA. RESULTS: TSK hearts had up to twofold greater protein and collagen biosynthesis and 2.5-fold greater type VI collagen content (400 micrograms v 156 micrograms). Fibroblasts cultured from TSK mice hearts displayed up to threefold higher steady state concentrations of alpha 2(VI) collagen mRNA than normal myocardial fibroblasts. CONCLUSIONS: Hearts from TSK mice showed increased protein and collagen biosynthesis and increased myocardial content of type VI collagen compared with hearts from age matched normal mice. Also, fibroblast cultures from TSK mice myocardium showed increased expression of the alpha 2(VI) collagen gene, indicating that increased transcription of type VI collagen genes may be responsible for the accumulation of this collagen in myocardium from TSK mice.

Report on the quality of life analysis from the phase III trial of pion versus photon radiotherapy in locally advanced prostate cancer.

This report examines the quality of life (QOL) of 215 patients entered into a randomised trial between pion and photon radiotherapy for prostate cancer at a single institution. The survival and local control results of the trial were equivalent in both arms. A modification of the Rotterdam Symptom Checklist (RSCL) was used to assess QOL. Global QOL, toxicity and physical scores were found to be worse in pion-treated patients at the end of treatment (P<0.001, P<0.001, and P=0.02 respectively). There are no long-term differences in the QOL of pion- versus photon-treated patients. Sexual function was a concern for patients even at baseline. There was a progressive loss of sexual interest and erectile function. There was a significant impact from hormonal therapy at relapse. Hormonal treatment produced a stepwise significant worsening in global QOL, particularly for physical and psychological domains.

Performance of a submerged aerated filter and a rotating biological contactor under dynamic loading conditions.

Two types of small wastewater treatment systems were studied for their performance under normal conditions, including the hydraulic peak flows associated with small systems connected to just one house. Furthermore, the systems were subjected to a 7-day starvation period to simulate the effect of a holiday from home. The systems studied are (1) a combined submerged aerated filter-activated sludge system and (2) a rotating biological contactor system. Both the organic removal and the nitrification process were closely monitored. During normal operation, very good treatment results were achieved. The combined SAF-AS system realized 95% BOD removal, 88% COD removal and 94% NH4-N removal. The RBC system removed 92% of the BOD, 89% of the COD and 99% of the ammonium nitrogen. Both systems do not experience severe problems dealing with the lack of influent for a duration of seven days. The effluent concentrations did not change much, except for a small peak of nitrite which was present in all tests. However, both the ammonium oxidizing and the nitrite oxidizing bacterial populations were still active, as evidenced by the continued removal of ammonium and formation of nitrate.

Treatment of skeletal muscle injury: a review.

Skeletal muscle injuries are the most common sports-related injuries and present a challenge in primary care and sports medicine. Most types of muscle injuries would follow three stages: the acute inflammatory and degenerative phase, the repair phase and the remodeling phase. Present conservative treatment includes RICE (rest, ice, compression, elevation), nonsteroidal anti-inflammatory drugs (NSAIDs) and physical therapy. However, if use improper, NSAIDs may suppress an essential inflammatory phase in the healing of injured skeletal muscle. Furthermore, it remains controversial whether or not they have adverse effects on the healing process or on the tensile strength. However, several growth factors might promote the regeneration of injured skeletal muscle, many novel treatments have involved on enhancing complete functional recovery. Exogenous growth factors have been shown to regulate satellite cell proliferation, differentiation and fusion in myotubes in vivo and in vitro, TGF-ß1 antagonists behave as inhibitors of TGF-ß1. They prevent collagen deposition and block formation of muscle fibrosis, so that a complete functional recovery can be achieved.

Local structures of mesoporous bioactive glasses and their surface alterations in vitro: inferences from solid-state nuclear magnetic resonance.

We review the benefits of using (29)Si and (1)H magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy for probing the local structures of both bulk and surface portions of mesoporous bioactive glasses (MBGs) of the CaO-SiO(2)-(P(2)O(5)) system. These mesoporous materials exhibit an ordered pore arrangement, and are promising candidates for improved bone and tooth implants. We discuss experimental MAS NMR results from three MBGs displaying different Ca, Si and P contents: the (29)Si NMR spectra were recorded either directly by employing radio-frequency pulses to (29)Si, or by magnetization transfers from neighbouring protons using cross polarization, thereby providing quantitative information about the silicate speciation present in the pore wall and at the MBG surface, respectively. The surface modifications were monitored for the three MBGs during their immersion in a simulated body fluid (SBF) for intervals between 30 min and one week. The results were formulated as a reaction sequence describing the interconversions between the distinct silicate species. We generally observed a depletion of Ca(2+) ions at the MBG surface, and a minor condensation of the silicate-surface network over one week of SBF soaking.

Solid-State P and H NMR Investigations of Amorphous and Crystalline Calcium Phosphates Grown Biomimetically From a Mesoporous Bioactive Glass.

By exploiting (1)H and (31)P magic-angle spinning nuclear magnetic resonance (NMR) spectroscopy, we explore the proton and orthophosphate environments in biomimetic amorphous calcium phosphate (ACP) and hydroxy-apatite (HA), as grown in vitro at the surface of a 10CaO-85SiO(2)-5P(2)O(5) mesoporous bioactive glass (MBG) in either a simulated body fluid or buffered water. Transmission electron microscopy confirmed the presence of a calcium phosphate layer comprising nanocrystalline HA. Two-dimensional (1)H-(31)P heteronuclear correlation NMR established predominantly (1)H(2)O↔(31)PO(4) (3-) and O(1)H↔(31)PO(4) (3-) contacts in the amorphous and crystalline component, respectively, of the MBG surface-layer; these two pairs exhibit distinctly different (1)H→(31)P cross-polarization dynamics, revealing a twice as large squared effective (1)H-(31)P dipolar coupling constant in ACP compared with HA. These respective observations are mirrored in synthetic (well-crystalline) HA, and the amorphous calcium orthophosphate (CaP) clusters that are present in the pristine MBG pore walls: besides highlighting very similar local (1)H and (31)P environments in synthetic and biomimetic HA, our findings evidence closely related NMR characteristics, and thereby similar local structures, of the CaP clusters in the pristine MBG relative to biomimetic ACP.

Characterisation of sol-gel prepared (HfO2)x(SiO2)1-x (x=0.1, 0.2 and 0.4) by 1H, 13C, 17 O and 29Si MAS NMR, FTIR and TGA.

The HfO2-SiO2 system is attracting interest as a possible new dielectric material in semiconductor devices. Knowledge of the location of hafnium within the silica network and the effect hafnium has on the structure will be central to the successful use of this material system in this application. Here, sol-gel techniques have been used to manufacture (HfO2)x(SiO2)1-x samples (x=0.1, 0.2 and 0.4, each heat treated at 250, 500 and 750 degrees C) and these have been characterised by magic angle spinning (MAS) NMR (1H, 13C, 17 O, 29Si), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis. 29Si MAS NMR showed that increasing the hafnia content decreases the connectivity of the silicate network, i.e. increases the range of differently connected SiO4 (Qn) units with more having increased numbers of non-bridging oxygens (i.e. lower n). FTIR and 17 O MAS NMR showed unequivocally that the x=0.4 sample phase-separated at higher temperatures, while in the x=0.1 sample the hafnium was homogeneously mixed into the SiO2 phase without any phase separation.

Post-mortem angiographic and histologic findings of coronary artery fibromuscular dysplasia.

The present report highlights on exceptional angiographic and histologic features of coronary artery fibromuscular dysplasia in a young man complaining of chest discomfort during strenuous exercise. The striking features of fibromuscular dysplasia were the relative proximal localization of the lesion in left anterior descending coronary artery, the extensive length of the lesion, and the exclusive involvement of the intima producing a diffuse regular narrowing lesion. An eccentric intimal proliferation of the small left anterior descending coronary artery branches along their epicardial and intramural course was additionally demonstrated. No involvement of other coronary arteries or arteries of any other organs was observed.

Increased alpha 1(I) procollagen gene expression in tight skin (TSK) mice myocardial fibroblasts is due to a reduced interaction of a negative regulatory sequence with AP-1 transcription factor.

The TSK mouse, a model of fibrosis, displays exaggerated connective tissue accumulation in skin and visceral organs including the heart. To study the mechanisms of myocardial fibrosis in TSK mice, we established several strains of TSK mice myocardial fibroblasts in culture and examined the regulation of collagen gene expression in these cells. These strains displayed increased collagen gene expression in comparison with myocardial fibroblasts established from normal mice. On an average, the TSK myocardial fibroblast cultures showed a 4-fold increase in collagen synthesis and 4.4- and 3.6-fold increases, respectively, in alpha 1(I) and alpha 1(III) collagen mRNA steady state levels. The increased alpha 1(I) and alpha 1(III) collagen mRNA levels were mainly due to increased transcription rates (3.4- and 3.8-fold higher, respectively) of the respective genes. Furthermore, we showed that the up-regulation of alpha 1(I) procollagen gene transcription in TSK mice myocardial fibroblasts was due to the lack of the strong inhibitory influence of a regulatory sequence contained in the promoter region encompassing nucleotides -675 to -804. Nuclear extracts from TSK mice myocardial fibroblasts showed lower DNA binding activity to oligonucleotides spanning the mapped regulatory sequence as well as to a consensus AP-1 sequence, but not to a consensus SP-1 sequence, and supershift experiments with an AP-1 antibody confirmed the interaction of these oligonucleotides with AP-1 protein. These observations indicate that a strong negative regulatory sequence contained within -0.675 to -0.804 kilobase of the alpha 1(I) procollagen promoter binds AP-1 transcription factor and mediates inhibition of gene transcription in normal murine myocardial fibroblasts. The TSK mice myocardial fibroblasts lack this inhibitory control, due to lower available amounts and/or decreased binding activity to this inhibitory sequence, and hence display increased alpha 1(I) procollagen gene expression.

Re-use of biologically treated wastewater of a brewery.

Despite excessive rainfalls, Flanders is dealing with a water deficiency. A rational use of water is a necessity. Apart from the prevention principle, the re-use of biologically treated wastewater (bio-effluent) is increasingly considered. From earlier research it is known that reverse osmosis (RO) is necessary for the elimination of salts and low molecular compounds from the bio-effluent. A thorough pretreatment is necessary to remove drastically the suspended solids, which are harmful to the reverse osmosis modules. This case study describes the experiments performed by SEGHERSbetter technology for Water N.V. on the treatment of wastewater effluent from a brewery. A comparative study between sand filtration (SF), in-line coagulation with sand filtration and ultrafiltration (UF) as a pretreatment was made. UF proved to be the best pretreatment for RO for the treatment of brewery bio-effluent. Finally, an economic evaluation of the membrane system (UF followed by RO) was made. The calculated total cost for the system is 0.26 Euros per m3 produced water. Investment costs and operation cost are also discussed.

Image analysis as a monitoring tool for activated sludge properties in lab-scale installations.

An important step in the battle against filamentous bulking is the development of a monitoring system for activated sludge properties. Therefore, a fully automatic image analysis method for recognizing and characterizing flocs and filaments in activated sludge images has been developed. This procedure has been subsequently used to monitor activated sludge properties in a lab-scale installation. The results of a 100-days experiment indicate that the image information correlates well with the evolution of standard settling properties, in this case the Sludge Volume Index. It is shown that, at the onset of severe filamentous bulking, there is an increase in total filament length on the one hand, and a significant change in floc shape on the other hand.

Identification of benzene metabolites in dermal fibroblasts as nonphenolic: regulation of cell viability, apoptosis, lipid peroxidation and expression of matrix metalloproteinase 1 and elastin by benzene metabolites.

The skin is exposed to benzene and its derivatives, prevalent environmental chemicals. They may impair the structural integrity of the skin by increased expression of matrix metalloproteinase 1 (MMP-1; degrades structural collagen) and elastin, synthesized primarily by the dermal fibroblasts. We examined the metabolism of benzene in dermal fibroblasts and identified the benzene metabolites as toluene, benzaldehyde, aniline and benzoic acid. These metabolites were not toxic to the cells with regard to cell viability, apoptosis and lipid peroxidation, unlike the phenolic benzene metabolites (hydroquinone, t-butyl hydroquinone and phenol) or hydrogen peroxide. Toluene and phenol, which compose cigarette smoke, and benzaldehyde stimulated MMP-1 and/or elastin expression. In summary, the dermal fibroblasts metabolize benzene to nonphenolic metabolites that are less toxic to the cellular components than the phenolic benzene derivatives. Toluene, benzaldehyde and phenol can directly cause facial wrinkling and impaired structural integrity by upregulating MMP-1 and/or elastin.