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Notes: Digestive enzymes in faeces have been reported to posses skin irritation potential. The present study was designed to investigate the in vivo irritant potentials of faecal concentrations of proteolytic and lipolytic digestive enzymes in bile salt mixtures. In a 21-day cumulative irritation assay, clinical evaluation and noninvasive bioengineering techniques were used. 5 days occlusive exposure to phosphate buffer (pH = 8) caused no visual skin damage but reflectance spectroscopy demonstrated significant vasodilation (p 〈 0.01) and increases in transepidermal water loss (TEWL) and skin pH were also observed (p 〈 0.01). These increases were still present at days 12 and 19. Occlusive exposure to physiologic concentrations of faecal enzymes resulted in significant visual and objective scores at day 5, 12, and 19, with increased readings as a function of exposure time (p 〈 0.01). The enzyme mixture containing lipase caused delayed onset of skin erythema and epidermal barrier disruption compared to elastase and chymotrypsin containing solutions. Prolonged occlusive exposure to digestive enzymes in faecal concentrations caused severe skin erythema and epidermal barrier disruption in a human model, suggesting a possible etiologic role of digestive enzymes in perianal, circumstomal or diaper dermatitis.

Notes: SUMMARY. 1. Mean motion and near-bed flows in streams and rivers can be described using a classification derived from fairly simple field measurements. Our proposed classification is ecologically useful because it incorporates the combined effects of velocity, depth and substrate roughness to provide a means of quantifying the flow regimes occurring within the microhabitats of stream benthos.2. Mean motion is characterized by the Reynolds number and the Froude number. Both are easily calculated, and because they are dimensionless they provide a means of comparing flows at different sites.3. Five categories of near-bed flows (i.e. the flow microenvironments of stream benthos) are recognized. Flow may be hydraulically smooth or hydraulically rough and the latter category is subdivided further into: chaotic flow, wake interference flow, isolated roughness flow and skimming flow. Hydraulically smooth flows occur in sections of a river bed with fine sediments (e.g. sands, muds and clays). over flat sheets of bedrock, or in association with the flat blades of submerged macrophytes. Hydraulically rough flows occur where the substrate elements are larger (e. g. pebbles, cobbles and boulders) and are a function of substrate roughness and the depth of flow relative to the height of the roughness elements. Chaotic flows and wake interference flows predominate in riffles whilst isolated roughness flows and skimming flows are more likely to be a feature of runs.4. Conventional stream sampling methods (e.g. the Surber and box or cylinder samplers) may collect across several different flow microhabitats. Our classification should enable different flow microenvironments to be recognized and so sampled more appropriately which, in turn, may reduce apparent clumping and the wide confidence intervals of benthic population estimates. Because our classification identifies ‘patches’ within the flow regime associated with the stream bed it enables stream ecologists to generate testable hypotheses regarding the distribution and abundance of benthic species in response to flow.5. Our classification identifies spatial patterns in the flow regimes associated with the stream bed. Temporal patterns have not been identified: however, predictable changes in spatial patterns will resuh from temporal changes in stream discharge.

Notes: 1. Flow conditions were modified over patches of river bed in three rivers in south-western Australia to determine the effects of turbulence on benthic invertebrate communities.2. Artificial structures to increase downstream turbulence were developed in a laboratory flume. In the field, these increased turbulence intensity by 35% for a 20% reduction in velocity.3. Patches of gravel were placed in each river and turbulence-generating structures allocated randomly to half of these, creating treatment patches. An acoustic Doppler velocimeter was used to measure flow conditions over both treatment and control patches at several heights above the bed. After 6 weeks, the invertebrate fauna of the gravel patches were sampled to examine the response to modified flow conditions.4. The treatments increased relative turbulence intensity twofold for a reduction in velocity of between 3 and 5 cm s−1, but turbulence intensity was significantly higher in only one of the three rivers.5. There were no significant effects of increased relative turbulence intensity on any aspect of the invertebrate assemblage. This may be a result of the fairly small increase in relative turbulence intensity created during the experiment, the spatial scale of the manipulation or the types of stream community studied.

Notes: Summary. Colposcopic, histological and cytological characteristics of 168 consecutive patients attending a colposcopy clinic were reviewed. A group of patients demonstrated a cluster of histological features previously related to possible human papilloma virus infection of cervical epithelium, including particularly koilocytosis, double nucleation and dyskeratosis. These patients had a significantly greater occurrence of colposcopic ‘finger-like’ lesion outline and colposcopic impression of warty change, but not of other specific colposcopic features. Over two-thirds of patients with histological warty features did not show these colposcopic changes. Cytological changes previously related to warty lesions did not occur commonly, and appeared to underestimate the histological occurrence of such changes. Histological changes considered to represent CIN were uncommon in patients who said that they had begun sexual activity less than 10 years ago, whereas patients with warty characteristics on histology showed no such bias.

Notes: Summary. Of 420 patients attending a colposcopy clinic 204 were treated with outpatient cryosurgery for cervical intraepithelial neoplasia. It was possible to assess a definite outcome of therapy in 159 patients, and the lesion was successfully eradicated in 87% of them. Treatment failure appeared to be more common in patients of high parity, when the lesion extended into the cervical canal, and in those patients with large lesions. Failure appeared to be unrelated to patient age and to the histological grade of the lesion. In subsequent pregnancies utero-cervical function was preserved.

Notes: The case is described of a 20 year old pregnant woman with clear cell adenocarcinoma of the vagina who had been exposed to diethyl stilboestrol in utero. This is the second of three cases known to have occurred in Britain. The importance of radical treatment is discussed. Neither cervical nor vaginal intra-epithelial neoplasia were seen histologically, although squamous metaplasia was widespread, and in some areas was immature and showed atypical features which could be misinterpreted as intra-epithelial neoplasia. An area of atypical adenosis was noticed, a hitherto rarely observed feature.

Notes: 1. AusRivAS (Australian River Assessment Scheme) models were developed, using macroinvertebrates as indicators, to assess the ecological condition of rivers in Western Australia as part of an Australia-wide program. The models were based on data from 188 minimally disturbed reference sites and are similar to RIVPACS models used in Britain. The major habitats in the rivers (macrophyte, channel) were sampled separately and macroinvertebrates collected were identified to family level.2. Laboratory sorting of preserved macroinvertebrate samples recovered about 90% of families present when 150 animals were collected, whereas live picking in the field recovered only 76%.3. Reference sites clustered into five groups on the basis of macroinvertebrate families present. Using seven physical variables, a discriminant function allocated 73% of sites to the correct classification group. A discriminant function based on seven physical and two chemical variables allocated 81% of sites to the correct group. However, when the same reference sites were re-sampled the following year, the nine variable discriminant function misallocated more sites than the seven variable function, owing to annual fluctuations in water chemistry that were not accompanied by changes in fauna.4. In preliminary testing, the wet season channel model correctly assessed 80% of reference sites as undisturbed in the year subsequent to model building (10% of sites were expected to rate as disturbed because the 10th percentile was used as the threshold for disturbance). Nine sites from an independent data set, all thought to be disturbed, were assessed as such by the model. Results from twenty test sites, chosen because they represented a wide range of ecological condition, were less clear-cut. In its current state the model reliably distinguishes undisturbed and severely disturbed sites. Subtle impacts are either detected inconsistently or do not affect ecological condition.

Notes: 1. The northern half of Western Australia is a large, sparsely populated area with a climate that ranges from monsoonal in the Kimberley to arid in the Gascoyne and Pilbara regions. The aquatic invertebrate fauna is poorly known.2. Fifty-one sites located on 14 river systems were sampled three times between August 1994 and October 1995. A total of 90 taxa, most identified to family level, were collected. The fauna was dominated by insects, which constituted 74% of the total number of taxa collected.3. Major habitats at each site were sampled separately and sites with more habitats tended to have a richer fauna. All habitats showed significant differences in taxonomic richness between regions. Family richness decreased with increasing latitude, being highest in the Kimberley region and lowest in the Gascoyne.4. Despite the differences in taxon richness between regions, community composition of the aquatic invertebrate fauna at the family level did not differ greatly. Four major groups of sites were identified by cluster analysis, based on the invertebrate families present at each site, but differences between groups were small.5. Significant temporal variation in taxon richness was found in channel habitat but not the three other habitats sampled (riffle, macrophyte, pool-rocks). Community composition in channel habitat varied temporally among groups of sites identified by cluster analysis but the pattern was not consistent.