Suction blister lesions and epithelialization monitored by optical coherence tomography.

BACKGROUND/PURPOSE: Our objective was to assess epithelialization of suction blister lesions by optical coherence tomography (OCT) and benchmark it to histology using epidermal thickness (ET) as the primary outcome. METHODS: Thirty-two healthy volunteers were recruited to Study 1 and 2. One 10-mm suction blister was raised on each buttock, and the blister roof was excised. Lesions were covered with moisture-retaining dressing. In Study 1, the lesions were OCT-scanned on day 0 (D0), D2 and D4 and excised for histological examination. In Study 2, the progress of epithelialization and skin barrier function were monitored to D14. RESULTS: ET increased from D0 to D2 by 46 µm (P<.001) and from D2 to D4 by 19 µm (P=.004). Compared with histology, OCT overestimated the presence of the epithelium (P<.0001) and ET on D4. Reliable measurements were obtained when the ET of the lesions reached the ET of the normal epidermis from D5-D7 and onwards. The ET development was reflected in decreased transepidermal water loss. CONCLUSION: We found that the OCT technique was poorly discriminative with respect to the neoepithelium and the moist lesion surface material in the early postinjury period. In the later stages, OCT seemed valuable for estimating the advancement of epithelialization.

Life cycle assessment applied to wastewater treatment: state of the art.

Life cycle assessment (LCA) is a technique to quantify the impacts associated with a product, service or process from cradle-to-grave perspective. Within the field of wastewater treatment (WWT) LCA was first applied in the 1990s. In the pursuit of more environmentally sustainable WWT, it is clear that LCA is a valuable tool to elucidate the broader environmental impacts of design and operation decisions. With growing interest from utilities, practitioners, and researchers in the use of LCA in WWT systems, it is important to make a review of what has been achieved and describe the challenges for the forthcoming years. This work presents a comprehensive review of 45 papers dealing with WWT and LCA. The analysis of the papers showed that within the constraints of the ISO standards, there is variability in the definition of the functional unit and the system boundaries, the selection of the impact assessment methodology and the procedure followed for interpreting the results. The need for stricter adherence to ISO methodological standards to ensure quality and transparency is made clear and emerging challenges for LCA applications in WWT are discussed, including: a paradigm shift from pollutant removal to resource recovery, the adaptation of LCA methodologies to new target compounds, the development of regional factors, the improvement of the data quality and the reduction of uncertainty. Finally, the need for better integration and communication with decision-makers is highlighted.

Modelling micro-pollutant fate in wastewater collection and treatment systems: status and challenges.

This paper provides a comprehensive summary on modelling of micro-pollutants' (MPs) fate and transport in wastewater. It indicates the motivations of MP modelling and summarises and illustrates the current status. Finally, some recommendations are provided to improve and diffuse the use of such models. In brief, we conclude that, in order to predict the contaminant removal in centralised treatment works, considering the dramatic improvement in monitoring and detecting MPs in wastewater, more mechanistic approaches should be used to complement conventional, heuristic and other fate models. This is crucial, as regional risk assessments and model-based evaluations of pollution discharge from urban areas can potentially be used by decision makers to evaluate effluent quality regulation, and assess upgrading requirements, in the future.

Sustainability assessment of advanced wastewater treatment technologies.

As a consequence of the EU Water Framework Directive more focus is now on discharges of hazardous substances from wastewater treatment plants and sewers. Thus, many municipalities in Denmark may have to adopt to future advanced treatment technologies. This paper describes a holistic assessment, which includes technical, economical and environmental aspects. The technical and economical assessment is performed on 5 advanced treatment technologies: sand filtration, ozone treatment, UV exclusively for disinfection of pathogenic microorganisms, membrane bioreactor (MBR) and UV in combination with advanced oxidation. The technical assessment is based on 12 hazardous substances comprising heavy metals, organic pollutants, endocrine disruptors as well as pathogenic microorganisms. The environmental assessment is performed by life cycle assessment (LCA) comprising 9 of the specific hazardous substances and three advanced treatment methods; sand filtration, ozone treatment and MBR. The technical and economic assessment showed that UV solely for disinfection purposes or ozone treatment is the most advantageous advanced treatment methods if the demands are restricted to pathogenic microorganisms. In terms of sustainability, sand filtration is the most advantageous method based on the technical and environmental assessment due to the low energy consumption and high efficiency with regards to removal of heavy metals.

Weighing environmental advantages and disadvantages of advanced wastewater treatment of micro-pollutants using environmental life cycle assessment.

Much research and development effort is directed towards advances in municipal wastewater treatment aiming at reducing the effluent content of micro-pollutants and pathogens. The objective is to further reduce the eco-toxicity, hormone effects and pathogenic effects of the effluent. Such further polishing of the effluent, however, involves an environmental trade-off: the reduction in eco-toxicity, hormone effects, etc. will happen at the expense of increased resource- and energy consumption. Obviously, at some point of further advances, there must be an 'environmental break-even'. This trade-off was investigated using Life Cycle Assessment (LCA) methodology and based on a literature review of advanced treatment performance. The LCA evaluation comprised sand filtration, ozonation and MBRs and assessed the effect of extending existing tertiary treatment with these technologies on a variety of micro-pollutants being: heavy metals (Cd, Pb, Ni), endocrine disruptors (E2 and EE2), PAH, DEHP, and detergents (LAS & NPE). It was found, in some of the studied scenarios, that more environmental impact may be induced than removed by the advanced treatment. The study showed that for the 3 technologies, sand filtration has the best balance between prevented and induced impacts, and sand filtration proved to have a net environmental benefit under the assumptions used in the study. But the outcome of the study suggests that this is not always the case for ozonation and MBR.

Effect of a short course of 1,25-dihydroxyvitamin D3 on biochemical markers of bone remodeling in adult male volunteers.

To investigate the stimulatory effect of vitamin D on biochemical markers of bone remodeling, 15 normal men (aged 26-45 years, mean 33.2) were treated orally with 1,25-dihydroxyvitamin D3, 2 micrograms daily for 7 days, and followed for a total of 16 weeks. Serum concentrations of 1,25-dihydroxyvitamin D3 rose 43% during the first week (p less than 0.01), with no significant alteration in the level of 25-hydroxyvitamin D3. Serum level of immunoreactive parathyroid hormone (1-84) (iPTH) decreased markedly (p less than 0.02), and the maximal renal reabsorption capacity of phosphate (TmP/GFR) increased (p less than 0.05), both indicating the impact of the raised vitamin D level on target tissues. Serum phosphate and serum calcium increased during the treatment week (p less than 0.05), as did the fasting renal excretion of phosphate and calcium (p less than 0.01). However, a gradual fall in the excretion of hydroxyproline was seen in the observation period. The serum activity of acid phosphatase increased in the first weeks after vitamin D treatment, reaching significance at the end of week 2 (p less than 0.05). Acid phosphatase activity was still increased at the end of the observation period (p less than 0.02). These observations suggest a synchronization and recruitment of new bone resorptive cells. The immediate response to 1,25-dihydroxyvitamin D administration on the biochemical markers of formative bone cells was a marked increase in the serum level of osteocalcin (BGP), (p less than 0.002) with a gradually fall during the next weeks. A secondary increase, however, was observed in the last two months of the follow-up period.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of carbonic anhydrase inhibition on calcium and bone homeostasis in healthy postmenopausal women.

Carbonic anhydrase localized in bone resorptive cells generates the protons necessary for bone resorption. Inhibition of the enzyme is a potential mechanism for decreasing bone resorption. Eight healthy post-menopausal women received oral acetazolamide 250 mg twice daily for 28 d. Bone resorption, evaluated by serum acid phosphatase activity and the renal excretion of hydroxyproline, was unaltered, as was bone formation estimated by serum levels of alkaline phosphatase and osteocalcin. The fasting renal excretion of calcium was increased, whereas serum ionized calcium was unchanged. The maximal renal reabsorption of phosphate decreased, but it was not an effect of PTH as it decreased significantly during the treatment period. In conclusion, no significant effect on biochemical markers of bone remodelling could be detected during the study period. The observed changes in calcium and phosphate metabolism may be secondary to the renal effect of acetazolamide.

Biochemical evidence of disturbed bone metabolism and calcium homeostasis in two types of autosomal dominant osteopetrosis.

Biochemical markers of bone resorption and bone formation were measured in 14 patients with autosomal dominant osteopetrosis, and compared with age- and sex-matched controls. There were eight patients with the radiological type I characterized by diffuse, symmetrical osteosclerosis with pronounced sclerosis of the skull and enlarged thickness of the cranial vault, and six patients with type II characterized by diffuse, symmetrical osteosclerosis, "Rugger-Jersey spine" and "endobones" (bone within a bone) in the pelvis. Serum levels of alkaline phosphatase and osteocalcin in types I and II did not differ from controls indicating normal bone formation. However, a significantly decreased fasting renal excretion of phosphate and hydroxyproline in both types compared with normal controls, suggests a reduced bone resorption. Serum levels of parathyroid hormone (PTH), albumin-corrected calcium, phosphate, and acid phosphatase were normal in type I. In type II serum levels of albumin-corrected calcium and PTH were significantly increased (p less than 0.05 and p less than 0.01). The level of acid phosphatase was markedly increased in this type (p less than 0.01). These findings suggest differences between the two types in calcium homeostasis and bone metabolism, and thus corroborate the evidence that the two radiological types reflect two different disorders of bone resorption.

Secretory otitis media--a question of surface activity in the eustachian tube?

An improved thin-layer chromatographic assay for monitoring phospholipid ratio in mucus was used to study the respiratory system distribution of children with and without secretory otitis media. Phosphatidylcholine, phosphatidylethanolamine and sphingomyelin abound, while only traces of other phospholipids are found. Analyses show more sphingomyelin and less phosphatidylcholine in the Eustachian tube and nose than in the lung, while phosphatidylethanolamine has about the same distribution. The phosphatidylcholine/sphingomyelin ratio is significantly less in Eustachian tube mucus from children with secretory otitis media compared with otologically healthy children, which indicates a different secretory pattern of the cells in the Eustachian tube of these children. The distribution of phospholipids in middle ear secretion is different from the distribution obtained from the Eustachian tube in children with secretory otitis media thus verifying a clearance 'blocking' of the tube caused by the disease.

The effect of L-carnitine on lipid metabolism in patients on chronic haemodialysis.

Twenty-one patients (median 49 years; range 20-72 years) on chronic haemodialysis (median: 54 months; range 16-154 months) were examined in a clinical controlled trial for the effect of carnitine on hyperlipoproteinaemia. Initial values of serum carnitine were within the normal range. Carnitine was added to the dialysis fluid to a final concentration of 100 mumol/l. The trial was carried out for 6 months, and the serum of fasting patients was analysed at monthly intervals for carnitine, triglycerides, HDL-cholesterol, LDL-cholesterol and apolipoprotein A and B. The loss of carnitine to the dialysis fluid also was examined, as was the retained amount in those receiving carnitine. We could not confirm the findings of others that carnitine produces lowering of serum triglycerides and increases of serum HDL-cholesterol. The study was extended for another year with ten patients; however, no change was observed in the lipid pattern.

Rediagnoses of closely related pigmented marine species of the genus Pseudokeronopsis (ciliophora, hypotrichida).

The morphology and the infraciliature of Pseudokeronopsis rubra [7, 10, 11], P. carnea [8] nov. comb, and P. flava [8] nov. comb, are redescribed using protargol silver staining, biometry, and chromatography. These species differ in the colour and composition of the pigment granules, the length of the midventral rows, the number of frontal cirri comprising the bicorona, and the number of transverse cirri. An albino strain of P. rubra shows a highly instable cortical pattern. Seven populations belonging to P. rubra (2 South Africa, Indopacific region), P. carnea (Helgoland, Denmark, Yugoslavia), and P. flava (Denmark) are biometrically characterized. A multiple comparison of 13 characters confirms a highly significant heterogeneity among all populations. The available literature on "red" coloured species of Pseudokeronopsis is reviewed. The data suggest a strong genetical and ecological radiation of this genus. There are probably some more "red" species, for instance a particular kind of Mediterranean population.

Value of saliva samples in monitoring carbamazepine concentrations in epileptic patients.

Simultaneous saliva and serum concentrations of carbamazepine (CBZ) were determined by enzyme immunoassay technique (EMIT) in 120 epileptic patients on long-term treatment with CBZ. Saliva specimens were collected after the patients had chewed paraffin for 5 min. The regression between serum and saliva concentrations of CBZ was linear. The correlation coefficient was 0.94 with a mean saliva/serum ratio of 0.31 (0.30-0.31, 95% confidence limits). The serum/saliva correlation coefficients r = 0.92 and r = 0.95, as well as the mean saliva/serum ratios, 0.31 and 0.31, were comparable in 83 patients in CBZ monotherapy and 37 patients receiving additional drugs. The paraffin chewing facilitated the saliva sampling greatly, but resulted only in a minor increase of the serum/saliva correlation coefficient, 0.90 to 0.94, based on 45 patients on CBZ monotherapy where saliva was sampled just before as well as after paraffin chewing. The method of saliva sampling failed in five patients (4%), but was otherwise applicable even in little children. The findings indicate that the concentrations of CBZ in saliva instead of serum can be used to monitor CBZ treatment in epileptic patients, thus obviating the necessity of painful venipunctures.