Verification of an alternative sludge treatment process for pathogen reduction at two wastewater treatment plants in Victoria, Australia.

At South East Water wastewater treatment plants (WwTPs) in Victoria, Australia, biosolids are stockpiled for three years in compliance with the State guidelines to achieve the highest pathogen reduction grade (T1), suitable for unrestricted use in agriculture and landscaping. However, extended stockpiling is costly, may increase odour nuisance and greenhouse gas emissions, and reduces the fertiliser value of the biosolids. A verification programme of sampling and analysis for enteric pathogens was conducted at two WwTPs where sludge is treated by aerobic and anaerobic digestion, air drying (in drying pans or solar drying sheds) and stockpiling, to enumerate and, if present, monitor the decay of a range of enteric pathogens and parasites. The sludge treatment processes at both WwTPs achieved T1 grade biosolids with respect to prescribed pathogenic bacterial numbers (<1 Salmonella spp. 50 g-1 dry solids (DS) and <100 Escherichia coli g-1 DS) and >3 log10 enteric virus reduction after a storage period of one year. No Ascaris eggs were detected in the influent to the WwTPs, confirming previous studies that the presence of helminth infections in Victoria is extremely low and that Ascaris is not applicable as a control criterion for the microbiological quality of biosolids in the region.

Land application of sewage sludge (biosolids) in Australia: risks to the environment and food crops.

Australia is a large exporter of agricultural products, with producers responsible for a range of quality assurance programs to ensure that food crops are free from various contaminants of detriment to human health. Large volumes of treated sewage sludge (biosolids), although low by world standards, are increasingly being recycled to land, primarily to replace plant nutrients and to improve soil properties; they are used in agriculture, forestry, and composted. The Australian National Biosolids Research Program (NBRP) has linked researchers to a collective goal to investigate nutrients and benchmark safe concentrations of metals nationally using a common methodology, with various other research programs conducted in a number of states specific to regional problems and priorities. The use of biosolids in Australia is strictly regulated by state guidelines, some of which are under review following recent research outcomes. Communication and research between the water industry, regulators and researchers specific to the regulation of biosolids is further enhanced by the Australian and New Zealand Biosolids Partnership (ANZBP). This paper summarises the major issues and constraints related to biosolids use in Australia using specific case examples from Western Australia, a member of the Australian NBRP, and highlights several research projects conducted over the last decade to ensure that biosolids are used beneficially and safely in the environment. Attention is given to research relating to plant nutrient uptake, particularly nitrogen and phosphorus (including that of reduced phosphorus uptake in alum sludge-amended soil); the risk of heavy metal uptake by plants, specifically cadmium, copper and zinc; the risk of pathogen contamination in soil and grain products; change to soil pH (particularly following lime-amended biosolids); and the monitoring of faecal contamination by biosolids in waterbodies using DNA techniques. Examples of products that are currently produced in Western Australia from sewage sludge include mesophilic anaerobically digested and dewatered biosolids cake, lime-amended biosolids, alum sludge and compost.

Chemokine-mediated migration of melanoma cells towards lymphatics--a mechanism contributing to metastasis.

The mechanisms that cause tumors such as melanomas to metastasize into peripheral lymphatic capillaries are poorly defined. Non-mutually-exclusive mechanisms are lymphatic endothelial cell (LEC) chemotaxis and proliferation in response to tumor cells (chemotaxis-lymphangiogenesis hypothesis) or LECs may secrete chemotactic agents that attract cancer cells (chemotactic metastasis hypothesis). Using migration assays, we found evidence supporting both hypotheses. Conditioned medium (CM) from metastatic malignant melanoma (MMM) cell lines attracted LEC migration, consistent with the lymphangiogenesis hypothesis. Conversely, CM from mixed endothelial cells or LECs, but not blood endothelial cells, attracted MMM cells but not non-metastatic melanoma cells, consistent with the chemotactic metastasis hypothesis. MMM cell lines expressed CCR7 receptors for the lymphatic chemokine CCL21 and CCL21 neutralizing antibodies prevented MMM chemotaxis in vitro. To test for chemotactic metastasis in vivo tumor cells were xenotransplanted into nude mice approximately 1 cm from an injected LEC depot. Two different MMM grew directionally towards the LECs, whereas non-metastatic melanomas did not. These observations support the hypothesis that MMM cells grow towards regions of high LEC density owing to chemotactic LEC secretions, including CCL21. This chemotactic metastasis may contribute to the close association between metastasizing tumor cells and peri-tumor lymphatic density and promote lymphatic invasion.

Allelotypes of primary cutaneous melanoma and benign melanocytic nevi.

A multistep genetic model of tumorigenesis, based on genetic alterations in benign and primary malignant lesions, has been proposed for neoplasms such as colonic carcinoma. However, evidence for a similar genetic progression in melanoma has relied heavily on findings in cultured lesions or metastases. We have investigated every autosomal arm for loss of heterozygosity in 41 primary cutaneous melanomas and 32 benign melanocytic nevi, and have investigated several chromosome arms that show loss in melanoma in 27 Spitz nevi (a nevus with histological similarities to melanoma). Loss of heterozygosity in primary melanoma was identified most frequently on chromosomes 9p (46%) at loci near the p16INK4 gene, 10q (31%), 6q (31%), and 18q (22%); loss of these chromosome arms were related to the progression of the melanoma. Only two benign melanocytic nevi (both of which showed atypical features on histology) demonstrated genetic alterations, including p9 loss in one case. In addition, two Spitz nevi contained interstitial deletions on chromosome 9p. Our findings show that loss of heterozygosity of 9p is not confined to melanoma, but that other uncultured melanocytic lesions can also display loss of this chromosome arm, and that other genetic changes (e.g., loss of 10q, 6q, and 18q) may be important in conveying the malignant phenotype to melanoma.

Prognostic significance of allelic losses in primary melanoma.

Loss of genetic material, including loss of loci on chromosome arms 6q, 9p, and 10q, occurs frequently in cutaneous melanoma but infrequently in benign melanocytic nevi or other melanocytic lesions, suggesting that these genetic alterations are important in the development and progression of melanoma. To examine whether allelic loss is of prognostic importance in melanoma, disease-free survival was related to loss of heterozygosity on 6q, 9p and 10q in 83 individuals with sporadic primary cutaneous melanoma. Loss of chromosome arms 6q and 10q were each significantly associated with a poorer clinical outcome (P=0.013 and P=0.001 respectively). In a subgroup of 41 subjects whose primary tumours were allelotyped, the fractional allelic loss (FAL) at 39 autosomal arms also significantly correlated with disease-free survival (P=0.013), with an increase in FAL associated with a poorer outcome; this association remained significant when controlled for tumour thickness (P=0.035). In addition, a greater proportion of cells were immunopositive for Ki67 antigen, p53 and p21WAF1 protein in the primary melanomas than in the benign melanocytic nevi, however, only p53 over-expression was significantly associated with improved survival (P=0.041).

Comparison of two preparatory techniques for urine cytology.

Two methods of preparation of urine for cytology were compared retrospectively. In method 1 cells in the urine were fixed after the preparation of the smear; in method 2 the cells were fixed before smear preparation. Urine cytology reports were correlated with subsequent histological analysis. The specificities of urine cytology using both methods were high (99%). The sensitivity using method 1 was 87%; using method 2 it was 65%. This difference was significant. The cell preparation technique therefore significantly changes the sensitivity of urine cytology. Cellular fixation after smear preparation is preferable to smear preparation after fixation.

Colour perception in pathologists: the Farnsworth-Munsell 100-hue test.

The value of many histological stains depends on the ability of the observer to differentiate colour. This ability was assessed in 30 histopathologists and cytopathologists of varying experience using the Farnsworth-Munsell 100-hue test. As a group, the pathologists performed better than a reference population. Twenty eight subjects showed a wide ranging ability to differentiate colour: none was colour blind. Three of the 30 pathologists, however, fell below the twentieth centile for normal subjects and only one was aware of this deficiency! They may unknowingly misinterpret subtle stains. Two of these three had specific and major defects which could affect their ability to interpret a wide range of less subtle stains. Those with the poorest colour discrimination were not those with the least experience of microscopy. Pathologists should be apprised of the importance of their ability to discriminate colour, and that formal colour vision testing of prospective histopathologists may be appropriate.

Rectal endosonography, a new technique for the preoperative staging of rectal carcinoma.

Endosonography of the rectum is a new and exciting technique which is having an increasing impact on the surgical and radiological community and is likely to have two principal applications in patients with rectal cancer. Firstly in the preoperative staging of the disease it has been shown to provide an objective reproducible method of assessment allowing the more accurate planning of treatment whether purely surgical or including some form of adjuvant treatment. Secondly in the follow up of patients who have already had surgery or radiotherapy it may be possible to detect in particular extrarectal local reoccurence at an early and treatable stage. Initial results with this technique are extremely promising but further long term studies are now needed to see whether it will improve overall survival or decrease local recurrence.

Detection of melanoma seeding during surgical procedures--an RT-PCR based model.

AIM: It has long been suggested that malignant cells may be shed into the blood stream during any given surgical procedure for cancer. A number of studies have now reported the detection of occult melanoma cells in peripheral blood using a reverse transcriptase polymerase chain reaction (RT-PCR) based assay. The principal aim of these studies has been to determine a prognostic value for the test and not to evaluate the influence of intervention upon results. METHODS: In this pilot study we aimed to determine whether the assay could be used as a model to detect cells that are seeded during surgery. Peripheral blood samples were obtained pre- and post-operatively on twenty patients undergoing surgery for malignant melanoma - ten with primary disease and ten undergoing regional lymphadenectomy. A further ten patients undergoing surgery for non-melanoma conditions provided controls. RESULTS: Using RT-PCR, it was possible to identify tyrosinase transcripts in the peripheral blood of one of ten patients undergoing excision of local disease and four of ten undergoing surgery for regional metastatic disease. CONCLUSION: It was concluded that this technique does enable detection of a greater percentage of RT-PCR findings post-operatively. This in turn may provide a means for optimizing or comparing surgical techniques and provides a potential guide in the use of adjuvant therapies.

Two case reports of breast carcinoma associated with prolactinoma.

Two cases of breast carcinoma associated with prolactinoma are presented. Literature review reveals only five previous case reports of this association. Both of our cases occurred in women, aged 55 and 34. Both were typical of the reported cases in that they had long histories of amenorrhea before diagnosis of prolactinomas and breast carcinomas. One patient had a three and a half year history of atypical ductal hyperplasia and a prominent intraduct component in the invasive tumor. Both had axillary lymph node metastases. The significance of the association of breast carcinoma with prolactinoma is discussed. Whereas studies in animals have shown prolactin to be an initiator and promoter of breast carcinoma, studies in humans have been inconclusive. Some studies have shown raised levels of prolactin in patients with breast carcinoma and their daughters, while others have not. The paucity of case reports linking breast carcinoma and prolactinoma may indicate that the association is mere coincidence, but studies evaluating the relationship between breast carcinoma and all forms of hyperprolactinemia need to be conducted before a causal link is dismissed. Prolactin may act as a cofactor with, for example, estrogen or stress, to induce breast carcinoma.

Perceptions of baby talk, frequency of receiving baby talk, and self-esteem among community and nursing home residents.

Community-living seniors (n = 113) and nursing home residents (n = 43) provided their impressions of baby-talk and neutral-talk scenarios and completed measures of functional health, need for succorance, and self-esteem. Two orthogonal dimensions were found in perceptions of baby talk: Warmth and Superiority. The personality trait of need for succorance was consistently associated with perceptions of warmth in baby talk, whereas functional health, age, and institutionalization were associated with perceptions of superiority. Significant interactions were found between perceptions of baby talk and frequency of receiving baby talk in the prediction of self-esteem, providing suggestive evidence for previously expressed concerns about potentially harmful effects of receiving baby talk on self-esteem among seniors who have negative perceptions of baby talk. However, older persons with positive perceptions of baby talk reported higher self-esteem when they frequently received baby talk, in accordance with person-environment theory. The self-esteem interaction for men occurred on the Superiority dimension, whereas the interaction for women occurred on the Warmth dimension.

The role of fixator frame stiffness in the control of fracture healing. An experimental study.

External skeletal fixation is used widely in the management of fractures. Frame configuration is known to affect frame stiffness and, thereby, the local mechanical environment at the fracture site. In previous investigations of the influence of mechanical conditions upon fracture healing, the frames have always been applied so that they influence the biological environment in different ways. As a result, the influence of stiffness, per se, could not be studied as a single variable, and its effect on the repair process remains unclear. In this study, using a standard osteotomy of the ovine tibia, stabilised by an external skeletal fixator, the local mechanical environment was altered solely by increasing the 'offset' distance between the bone and the fixator frame. The biological conditions at the fracture remained identical in both groups. Increasing the frame stiffness by 40%, brought about by reducing the offset distance of the fixator bar by 10 mm, caused a significant reduction in the rate of healing. In addition, the frame stiffness influenced the ground reaction force with greater weight-bearing in the initial stages in the more rigid group, but despite this, the resultant interfragmentary displacement in this group appeared to be insufficient to stimulate fracture healing. This work emphasises the importance of the local mechanical environment on the process of fracture healing. It also demonstrates the value of in vivo assessment of fracture stiffness as a means of monitoring mechanical events during fracture healing.

The bucket-handle tear of the meniscus. A clinical and arthrographic study.

A retrospective series of 272 operatively proven bucket-handle tears of the meniscus has been studied to define the natural history of the tear and to assess the accuracy of arthrography as a diagnostic technique. A simple twist, or a sporting injury accounted for most tears in the 196 patients on whom information was sufficient to allow analysis. There was, however, either no known trauma or merely a history of crouching in 20 per cent of patients. These were distributed evenly throughout the age range. Most of the 272 patients presented either with a locked knee (43 per cent) or with a history of locking (37 per cent). Fifty per cent of those with a previous history of locking but who were clinically unlocked at the time of operation, had displaced bucket-handle tears, indicating that unlocking of the knee joint frequently represents anterior extension of the tear, rather than relocation of the displaced fragment of meniscus. Significant meniscal tears were identified in 77 per cent of the 187 arthogram reports that were studied. Most errors in diagnosis seemed to occur when the separated fragment was hidden in the intercondylar notch and the peripheral rim was misinterpreted as an intact meniscus.

Nitrogen availability and indirect measurements of greenhouse gas emissions from aerobic and anaerobic biowaste digestates applied to agricultural soils.

Recycling biowaste digestates on agricultural land diverts biodegradable waste from landfill disposal and represents a sustainable source of nutrients and organic matter (OM) to improve soil for crop production. However, the dynamics of nitrogen (N) release from these organic N sources must be determined to optimise their fertiliser value and management. This laboratory incubation experiment examined the effects of digestate type (aerobic and anaerobic), waste type (industrial, agricultural and municipal solid waste or sewage sludge) and soil type (sandy loam, sandy silt loam and silty clay) on N availability in digestate-amended soils and also quantified the extent and significance of the immobilisation of N within the soil microbial biomass, as a possible regulatory mechanism of N release. The digestate types examined included: dewatered, anaerobically digested biosolids (DMAD); dewatered, anaerobic mesophilic digestate from the organic fraction of municipal solid waste (DMADMSW); liquid, anaerobic co-digestate of food and animal slurry (LcoMAD) and liquid, thermophilic aerobic digestate of food waste (LTAD). Ammonium chloride (NH4Cl) was included as a reference treatment for mineral N. After 48 days, the final, maximum net recoveries of mineral N relative to the total N (TN) addition in the different digestates and unamended control treatments were in the decreasing order: LcoMAD, 68%; LTAD, 37%, DMAD, 20%; and DMADMSW, 11%. A transient increase in microbial biomass N (MBN) was observed with LTAD application, indicating greater microbial activity in amended soil and reflecting the lower stability of this OM source, compared to the other, anaerobic digestate types, which showed no consistent effects on MBN compared to the control. Thus, the overall net release of digestate N in different soil types was not regulated by N transfer into the soil microbial biomass, but was determined primarily by digestate properties and the capacity of the soil type to process and turnover digestate N. In contrast to the sandy soil types, where nitrate (NO3-) concentrations increased during incubation, there was an absence of NO3- accumulation in the silty clay soil amended with LTAD and DMADMSW. This provided indirect evidence for denitrification activity and the gaseous loss of N, and the associated increased risk of greenhouse gas emissions under certain conditions of labile C supply and/or digestate physical structure in fine-textured soil types. The significance and influence of the interaction between soil type and digestate stability and physical properties on denitrification processes in digestate-amended soils require urgent investigation to ensure management practices are appropriate to minimise greenhouse gas emissions from land applied biowastes.

A systematic review of caregiver burden following stroke.

Abstract Caregiver burden following stroke is increasingly recognised as a significant health care concern. A growing number of studies have evaluated the patient, caregiver, and social support factors that contribute to increased caregiver burden. We conducted a systematic review of this literature to guide future research. A search of the MEDLINE, PsycINFO, CINAHL, and EMBASE databases (up to July 2008) and reference sections of published studies using a structured search strategy yielded 24 relevant articles. Studies were included if they evaluated predictors and/or correlates of caregiver burden in the setting of stroke. The prevalence of caregiver burden was 25-54% and remained elevated for an indefinite period following stroke. In studies that evaluated independent baseline predictors of subsequent caregiver burden, none of the factors reported were consistent across studies. In studies that assessed concurrent factors independently contributing to caregiver burden in the poststroke period, patient characteristics and social support factors were inconsistently reported. Several studies identified caregiver mental health and the amount of time and effort required of the caregiver as significant determinants of caregiver burden. Our findings highlight the need for more research to identify caregivers in need of support and guide the development and implementation of appropriate interventions to offset caregiver burden.

Caring for stroke survivors: baseline and 1-year determinants of caregiver burden.

BACKGROUND: Caregiver burden following stroke can have significant adverse health consequences for caregivers and threatens the recovery and successful rehabilitation of patients. Our objective was to identify patient factors that contribute to higher levels of caregiver burden. METHODS: We prospectively studied patients admitted to our stroke unit over a 2-year period (2001-2002). Data were collected at baseline and at 1 year. Caregiver burden was measured at 1 year using the Relatives Stress Scale (completed by 155 caregivers) and the Bakas Caregiver Outcomes Scale (143 caregivers). Explanatory patient factors at baseline included sociodemographic status, stroke severity, stroke sub-type, functional disability (Barthel Index), functional handicap (Oxford Handicap Scale and Modified Rankin Scale), and cognitive status (orientation, clock drawing). At 1 year, mental health and health-related quality of life were assessed using the Fatigue Impact Scale, Geriatric Depression Scale, Global Deterioration Scale, and 36-item Short Form Health Survey. RESULTS: The baseline patient factors predictive of caregiver burden by multiple regression analysis were older patient age (P<0.01), male gender (P<0.05), ischemic stroke (P<0.05), urinary incontinence (P<0.0001), and impaired clock drawing (P<0.05). At 1 year, significant correlates of caregiver burden were older patient age (P<0.05), male gender (P<0.01), poor mental health (P<0.05), functional handicap (P<0.05), and functional disability (P<0.001). CONCLUSIONS: The functional status of patients can be used to identify caregivers at risk of caregiver burden. Patient demographic variables, cognitive function, and mental health status may further expose vulnerable caregivers. These factors should be considered in the development of strategies to offset caregiver burden.

Collagenosis Nuchae: a case report of a rare and often misdiagnosed condition.

Enzinger and Weiss first described Collagenosis Nuchae (CN) or nuchal fibroma (NF) in 1988. CN is a rare benign soft tissue tumour that arises from the posterior cervical subcutaneous tissue with predilection for the interscapular and paraspinal regions. It is more common in males. CN has been reported in association with trauma, diabetes, scleredema and Gardner's syndrome. The true incidence of CN is probably higher than recognised and CN should be in the differential diagnosis of head and neck lesions. Histological examination is required for the diagnosis. Careful total excision provides cure and accurate diagnosis. The purpose of this study is to review the epidemiological, clinical, histopathological and radiological features of this rare lesion, which is often misdiagnosed.

Giant bathing trunk naevus with lymphadenopathy and unusual pathology.

Giant congenital melanocytic naevi remain a challenge to clinicians and histopathologists with respect to observation for malignant change and interpretation of histology findings, respectively. We report a 5-year-old boy with a giant bathing trunk naevus who, after multiple previous skin biopsies, developed lymphadenopathy. Biopsy from the lymph nodes demonstrated collections of naevomelanocytes within the lymph node. Interpretation of these findings and subsequent management is discussed.

Expression of VEGF(xxx)b, the inhibitory isoforms of VEGF, in malignant melanoma.

Malignant melanoma is the most lethal of the skin cancers and the UK incidence is rising faster than that of any other cancer. Angiogenesis - the growth of new vessels from preexisting vasculature - is an absolute requirement for tumour survival and progression beyond a few hundred microns in diameter. We previously described a class of anti-angiogenic isoforms of VEGF, VEGF(xxx)b, that inhibit tumour growth in animal models, and are downregulated in some cancers, but have not been investigated in melanoma. To determine whether VEGF(xxx)b expression was altered in melanoma, PCR and immunohistochemistry of archived human tumour samples were used. In normal epidermis and in a proportion of melanoma samples, VEGF(xxx)b staining was seen. Some melanomas had much weaker staining. Subsequent examination revealed that expression was significantly reduced in primary melanoma samples (both horizontal and vertical growth phases) from patients who subsequently developed tumour metastasis compared with those who did not (analysis of variance (ANOVA) P<0.001 metastatic vs nonmetastatic), irrespective of tumour thickness, while the surrounding epidermis showed no difference in expression. Staining for total VEGF expression showed staining in metastatic and nonmetastatic melanomas, and normal epidermis. An absence of VEGF(xxx)b expression appears to predict metastatic spread in patients with primary melanoma. These results suggest that there is a switch in splicing as part of the metastatic process, from anti-angiogenic to pro-angiogenic VEGF isoforms. This may form part of a wider metastatic splicing phenotype.