Identifying multiple stressor controls on phytoplankton dynamics in the River Thames (UK) using high-frequency water quality data.

River phytoplankton blooms can pose a serious risk to water quality and the structure and function of aquatic ecosystems. Developing a greater understanding of the physical and chemical controls on the timing, magnitude and duration of blooms is essential for the effective management of phytoplankton development. Five years of weekly water quality monitoring data along the River Thames, southern England were combined with hourly chlorophyll concentration (a proxy for phytoplankton biomass), flow, temperature and daily sunlight data from the mid-Thames. Weekly chlorophyll data was of insufficient temporal resolution to identify the causes of short term variations in phytoplankton biomass. However, hourly chlorophyll data enabled identification of thresholds in water temperature (between 9 and 19°C) and flow (<30m(3)s(-1)) that explained the development of phytoplankton populations. Analysis showed that periods of high phytoplankton biomass and growth rate only occurred when these flow and temperature conditions were within these thresholds, and coincided with periods of long sunshine duration, indicating multiple stressor controls. Nutrient concentrations appeared to have no impact on the timing or magnitude of phytoplankton bloom development, but severe depletion of dissolved phosphorus and silicon during periods of high phytoplankton biomass may have contributed to some bloom collapses through nutrient limitation. This study indicates that for nutrient enriched rivers such as the Thames, manipulating residence time (through removing impoundments) and light/temperature (by increasing riparian tree shading) may offer more realistic solutions than reducing phosphorus concentrations for controlling excessive phytoplankton biomass.

Riparian shading controls instream spring phytoplankton and benthic algal growth.

Dissolved oxygen (DO) concentrations showed a striking pattern in a multi-year study of the River Enborne, a small river in SE England. In each of three years (2010-2012), maximum DO concentrations were attained in mid-April, preceded by a period of steadily increasing diurnal amplitudes, followed by a steady reduction in both amplitude and concentration. Flow events during the reduction period reduce DO to low concentrations until the following spring. Evidence is presented that this pattern is mainly due to benthic algal growth which is eventually suppressed by the growth of the riparian tree canopy. Nitrate and silicate concentrations are too high to inhibit the growth of either benthic algae or phytoplankton, but phosphate concentrations might have started to reduce growth if the tree canopy development had been delayed. This interpretation is supported by evidence from weekly flow cytometry measurements and analysis of the diurnal, seasonal and annual patterns of nutrient concentrations. As the tree canopy develops, the river switches from an autotrophic to a heterotrophic state. The results support the use of riparian shading to help control algal growth, and highlight the risks of reducing riparian shade.

First results of Endonasal dilatation of the Eustachian tube (EET) in patients with chronic obstructive tube dysfunction.

For years, several surgical and non-surgical therapeutic strategies in Eustachian tube dysfunction have been described. The Endonasal dilatation of the Eustachian tube (EET) utilising a balloon catheter is a feasible option in patients with symptoms of chronic obstructive Eustachian tube dysfunction. However, long-term results in a large series are missing. In a prospective case series, 217 patients (342 cases) with symptoms of chronic Eustachian tube dysfunction underwent uni- or bilateral EET at the ENT Department of the University of Hamburg, Germany, between September 2010 and April 2013. A tube score consisting of the type of tympanogram and the R value of the tubomanometry was used to evaluate pre- and postoperative tube function. All patients underwent follow-up with a post-operative interval of 3-12 months. The mean value of the pre-treatment tube score was 2.23 ± 1.147 and significantly improved to 2.68 ± 1.011 1 year after EET. There was a significant increase in the tube score during follow-up. The co-variables time period, tympanoplasty and pressure range showed a significant impact on the tube score. EET is a minimally invasive and effective treatment of chronic obstructive tube dysfunction. It is a safe procedure without causing significant complications. Nevertheless, long-term results of larger, placebo-controlled multicentre studies are needed to confirm its effectiveness.

Adult encephalitis surveillance: experiences from an Australian prospective sentinel site study.

Few countries routinely collect comprehensive encephalitis data, yet understanding the epidemiology of this condition has value for clinical management, detecting novel and emerging pathogens, and guiding timely public health interventions. When this study was conducted there was no standardized diagnostic algorithm to aid identification of encephalitis or systematic surveillance for adult encephalitis. In July 2012 we tested three pragmatic surveillance options aimed at identifying possible adult encephalitis cases admitted to a major Australian hospital: hospital admissions searches, clinician notifications and laboratory test alerts (CSF herpes simplex virus requests). Eligible cases underwent structured laboratory investigation and a specialist panel arbitrated on the final diagnosis. One hundred and thirteen patients were initially recruited into the 10-month study; 20/113 (18%) met the study case definition, seven were diagnosed with infectious or immune-mediated encephalitis and the remainder were assigned alternative diagnoses. The laboratory alert identified 90% (102/113) of recruited cases including six of the seven cases of confirmed encephalitis suggesting that this may be a practical data source for case ascertainment. The application of a standardized diagnostic algorithm and specialist review by an expert clinical panel aided diagnosis of patients with encephalitis.

Characterising phosphorus and nitrate inputs to a rural river using high-frequency concentration-flow relationships.

The total reactive phosphorus (TRP) and nitrate concentrations of the River Enborne, southern England, were monitored at hourly interval between January 2010 and December 2011. The relationships between these high-frequency nutrient concentration signals and flow were used to infer changes in nutrient source and dynamics through the annual cycle and each individual storm event, by studying hysteresis patterns. TRP concentrations exhibited strong dilution patterns with increasing flow, and predominantly clockwise hysteresis through storm events. Despite the Enborne catchment being relatively rural for southern England, TRP inputs were dominated by constant, non-rain-related inputs from sewage treatment works (STW) for the majority of the year, producing the highest phosphorus concentrations through the spring-summer growing season. At higher river flows, the majority of the TRP load was derived from within-channel remobilisation of phosphorus from the bed sediment, much of which was also derived from STW inputs. Therefore, future phosphorus mitigation measures should focus on STW improvements. Agricultural diffuse TRP inputs were only evident during storms in the May of each year, probably relating to manure application to land. The nitrate concentration-flow relationship produced a series of dilution curves, indicating major inputs from groundwater and to a lesser extent STW. Significant diffuse agricultural inputs with anticlockwise hysteresis trajectories were observed during the first major storms of the winter period. The simultaneous investigation of high-frequency time series data, concentration-flow relationships and hysteresis behaviour through multiple storms for both phosphorus and nitrate offers a simple and innovative approach for providing new insights into nutrient sources and dynamics.

[New aspects of current therapeutic strategies in oropharyngeal carcinoma: highlights of the 2012 ASCO meeting]. / Neue Aspekte zur aktuellen Therapie von Oropharynxkarzinomen: Highlights vom ASCO-Kongress 2012.

Beside the surgical treatment of head and neck cancer, the concept of organ and function preserving therapy of locally advanced HNSCC (head and neck squamous cell carcinoma) especially of oropharyngeal origin is becoming increasingly important. The comparison of induction chemotherapy plus chemoradiation and primary concomitant chemoradiation has recently been the subject of randomized clinical trials. New combinations of different (chemo)radiation regimens and targeted therapies are also under investigation for HNSCC. Molecular markers predicting treatment efficacy as well as new potential targets are also being evaluated in several clinical trials. The good prognosis of HPV-associated HNSCC has sparked efforts to deintensify treatment to minimize therapy-related toxicities. The impact of specific therapies is growing due to the increasing incidence of young patients with HPV-positive carcinomas.

Impact of hydroxychloroquine therapy on chronic urticaria: chronic autoimmune urticaria study and evaluation.

BACKGROUND: Chronic urticaria (CU) imposes profound impairment on quality of life. Up to 60% of idiopathic CU is associated with autoimmune phenomena, and may respond to immunomodulation. Hydroxychloroquine offers potential efficacy for CU and is relatively benign compared with most other therapeutic approaches. OBJECTIVE: The aim of the chronic autoimmune urticaria study and evaluation was to evaluate the efficacy of hydroxychloroquine in patients with chronic idiopathic urticaria. METHODS: Twenty-one patients referred to the Immunology and Allergy Unit at John Hunter Hospital, New South Wales, Australia, with idiopathic CU were randomised to receive treatment with standard urticaria therapies (corticosteroids, H2-antihistamines, H1--antihistamines, doxepin) with or without hydroxychloroquine. Markers of autoimmunity, thyroid disease and mast-cell autoreactivity (autologous serum skin-prick testing (ASPT)) were assessed. Measures of urticaria control were compared at baseline and at 12 weeks for the 18 individuals who completed the study. These included urticaria scores, medication scores and quality-of-life indices. RESULTS: The hydroxychloroquine-treated group achieved significant improvements in quality of life as assessed by the global symptom severity score and the LAMY-7 (a quality of life index designed by Lamy, 7th revision) at 12 weeks (P < 0.01 and P < 0.05, respectively). No significant treatment effect on medication requirements or urticaria score was detected, although differences between treatment groups approached statistical significance for urticaria score and medication requirements (0.05 < P < 0.10). ASPT-reactivity did not correlate to hydroxychloroquine-responsiveness. Hydroxychloroquine was well tolerated. CONCLUSION: Immunomodulation with hydroxychloroquine is safe and appears to offer some efficacy as an intervention in CU.

The peripherally inserted central catheter (PICC): a prospective study of its natural history after cubital fossa insertion.

A prospective cohort study was undertaken to describe the natural history of the cubital fossa peripherally inserted central catheter (PICC), determine which factors influenced the hazard of complication and develop a standard methodology for evaluation of a PICC service. A total of 4349 patient days of PICC observation were analysed using survival analysis techniques. The median time to PICC removal for a complication was 60 days. The most common complications were phlebitis, malposition and tip migration. Complications usually occurred during the first week. There was only one episode of line-related sepsis. Size 3 French gauge catheters had a complication rate of 7.3 per 1,000 line days compared to 14.2 for 4 French catheters (hazard rate 1.26 90% CI 1.02 to 1.55). PICCs requiring two or more attempts at insertion were more likely to develop complications than those inserted at the first attempt: 20 per 1,000 line days vs 10.5 but the confidence intervals were wide (hazard rate 1.91, 90% CI 0.90 to 4.05). Operator (amongst the four experienced operators who inserted all PICCs), arm of placement, or medial or lateral placement in the cubitalfossa did not influence PICC survivaL

The status of HIV/AIDS nursing in Australia: a specialty in decline?

Since the introduction of highly active antiretroviral therapy (HAART), occasions of service for patients with HIV/AIDS have altered drastically. HIV/AIDS nurses perceived that this change in activity had caused an exodus from the specialty by experienced nurses, and those that remained were rapidly deskilling. A survey of nurses working in HIV/AIDS in Australia and New Zealand was conducted to assess the impact of HAART on nursing skills and retention. More than 72% of respondents reported that they had lost some or many clinical HIV/AIDS nursing skills. About 37% of nurses reported that they were losing confidence in their knowledge of the management of opportunistic infections and cancers. About 27% reported larger numbers of nurses leaving their specialty area than in previous years. To enable nurses to respond rapidly to a potential decline in the effectiveness of HAART, this loss in skills and knowledge must be addressed.

Malaria and its implications for public health in Far North Queensland: a prospective study.

This prospective study's objectives were to describe the features of all episodes of malaria diagnosed in Far North Queensland (excluding the Torres Strait) and to assess how much of a threat they posed to the area's public health. Over a three-year period, 216 episodes of malaria were diagnosed (158 Plasmodium vivax and 68 P. falciparum infections). Most (82%) of the infections were acquired in Papua New Guinea (PNG). Approximately 70% of the episodes occurred in Australian citizens, about half of whom were in malaria-endemic countries for work; the remainder travelled abroad for recreation. Three-quarters of the Australian citizens with malaria had taken either no or inadequate prophylaxis. Australian citizens who had taken adequate prophylaxis were much less likely to develop P. falciparum than other types of malaria compared to those who took either no or inadequate prophylaxis (p = 0.01). Gametocytes were present in 121 (56%) of the episodes of malaria. Mosquito surveillance was carried out in response to 38 (31%) of these gametocytaemic episodes. Significant numbers of Anopheles farauti sensu lato mosquitoes were found close to the residence of a patient in 4 (11%) of these episodes. Only two occasions when local transmission could have possibly occurred were recognised. We do not believe malaria poses an important threat to the health of the public in Far North Queensland. Nevertheless, it remains an important problem for those who travel abroad to malarious areas.

Plasmodium vivax malaria acquired in far north Queensland.

In February 1996, vivax malaria was diagnosed in a man from a remote community in far north Queensland who had not visited a malarious area for the past 19 years. Microscopy and DNA studies of blood from other residents of the community did not identify a source of infection. It was suspected the infection was transmitted by mosquitoes from a neighbour who had been infected in Papua New Guinea, but whose blood was not available for DNA tests.

An outbreak of hepatitis A in an intensive care unit.

We describe an outbreak of hepatitis A that occurred in an Intensive Care Unit (ICU) in a regional hospital in North Queensland. Seven people were infected including two patients, two close contacts of the index patient and three ICU nursing staff. The index case was admitted with an overdose and multiple trauma; he was not suspected to be incubating hepatitis A. The outbreak was initiated as a result of inadequate precautions taken whilst handling the index patient's bile. Problems identified upon reviewing the outbreak were inadequate terminal cleaning of equipment, food consumption in the ICU and inadequate handwashing practices. Implementation and maintenance of standard infection control practices is vital if further outbreaks of hospital-acquired hepatitis A and other enteric infections are to be avoided. We also suggest that the inactivated hepatitis A vaccine be considered for ICU staff.

Alternating nevirapine and zidovudine treatment of human immunodeficiency virus type 1-infected persons does not prolong nevirapine activity.

The potential use of an alternating treatment strategy with nevirapine and zidovudine in prolonging the antiretroviral effects of nevirapine was evaluated. Ten human immunodeficiency virus type 1 (HIV-1)-infected p24 antigen-positive persons who had not received prior antiretroviral therapy were treated for 9-13 weeks with an alternating regimen of 1 week of nevirapine (200 mg/day) and 3 weeks of zidovudine (600 mg/day). Serum p24 antigen levels declined during the first week of nevirapine treatment (median, 59%); however, subsequent courses of nevirapine were characterized by rising p24 antigen levels, while antigen levels remained stable or declined during zidovudine treatment. Serum beta 2-microglobulin levels and CD4+ cell counts exhibited similar responses. HIV-1 isolates obtained from 2 patients revealed 40- and 1000-fold reductions in nevirapine sensitivity after 8 weeks. These findings demonstrate that alternating treatment with zidovudine and nevirapine does not prolong the effectiveness of nevirapine and does not prevent the development of nevirapine resistance.

Evaluating the quality of ambulatory health care: a review of emerging methods.

While hospital quality evaluation activities have progressed dramatically in recent years, there has not been a comparable development and implementation of methods for the review and evaluation of ambulatory health care. Various technical problems regarding ambulatory records and the nature of ambulatory care itself have combined to retard the evolution of review methods. These problems are discussed, as are current efforts to overcome them. We have reviewed the relevant issues and literature and have attempted to provide a conceptual framework for better understanding the measurement of ambulatory health care quality. A selective bibliography of literature relating specifically to ambulatory care quality evaluation is presented as a guide to further study.