Update on the effects of a sierran wildfire on surface runoff water quality.

Wildfire has been shown to increase the short-term (1-3 yr) mobilization of mineral N and P in forest ecosystems of the Sierra Nevada Mountains and Lake Tahoe Basin. The ensuing effects on tributary and lake water quality are uncertain. The purpose of this investigation was to assess the impacts on runoff water quality over an intermediate time frame of 5 yr (2002-2007) after a wildfire event. Our design included fixed plots randomly placed within burned and unburned areas. Because each plot was sampled repeatedly during the study, we treated plots as repeated random effects in the analysis. We used a mixed model approach to analyze nutrient runoff concentrations and load for NH-N, NON and P in phosphate form (designated as ortho P or PO-P) where treatment (unburned vs. burned), time (pre-wildfire, post-wildfire year 1, year 2, etc.), and their interaction were fixed effects. Concentrations and loads of mineral N and P were higher in runoff from the burned areas immediately after wildfire. Because high water years may also contribute to higher runoff nutrient concentrations and loading, a wildfire followed by a high water year within the first season after a wildfire would likely have a much greater impact on runoff (and hence tributary) water quality than a wildfire followed by a low runoff water year.

Knowledge, attitudes and beliefs of health care workers towards influenza vaccination.

BACKGROUND: Influenza vaccination is routinely offered to health care workers in the U.K. to prevent nosocomial spread to patients and illness among health care workers. Despite its importance uptake has been low in the U.K. AIMS: To describe the knowledge, attitudes and behaviour of health care workers towards influenza vaccination offered as part of occupational health and to understand their relative importance in promoting uptake of influenza vaccine. We also sought to make comparisons with other vaccines more readily accepted as part of occupational health. METHODS: An online survey was distributed by e-mail to health care workers in the South Central Strategic Health Authority. The questionnaire included the following: demographic characteristics; vaccination status; and knowledge, attitudes and behaviour towards influenza, MMR and hepatitis B vaccination. We used logistic regression to identify the independent predictors of receipt of influenza vaccine. RESULTS: The survey was completed by 998 health care workers representing just over 1% of health care workers in the region. Of those, 69% thought that overall benefits of influenza vaccination were greater than the risks and inconvenience (versus 92% for hepatitis B and 86% for MMR). The following predicted receipt of influenza vaccine: belief that influenza poses a risk to one's own health (OR 3.74; 95% CI 2.45-5.71); belief that influenza vaccine is harmful (OR 0.25; 95% CI 0.16-0.37); and belief that influenza vaccine will protect patients (OR 2.96; 95% CI 1.89-4.62). CONCLUSIONS: Staff knowledge, attitudes and beliefs concerning influenza and its vaccine are an important predictor of uptake and should be a target for campaigns to promote uptake.

Genotype modulates age-related alterations in sensitivity to the aversive effects of ethanol: an eight inbred strain analysis of conditioned taste aversion.

Adolescent individuals display altered behavioral sensitivity to ethanol, which may contribute to the increased ethanol consumption seen in this age-group. However, genetics also exert considerable influence on both ethanol intake and sensitivity. Currently there is little research assessing the combined influence of developmental and genetic alcohol sensitivities. Sensitivity to the aversive effects of ethanol using a conditioned taste aversion (CTA) procedure was measured during both adolescence (P30) and adulthood (P75) in eight inbred mouse strains (C57BL/6J, DBA/2J, 129S1/SvImJ, A/J, BALB/cByJ, BTBR T(+) tf/J, C3H/HeJ and FVB/NJ). Adolescent and adult mice were water deprived, and subsequently provided with access to 0.9% (v/v) NaCl solution for 1 h. Immediately following access mice were administered ethanol (0, 1.5, 2.25 and 3 g/kg, ip). This procedure was repeated in 72 h intervals for a total of five CTA trials. Sensitivity to the aversive effects of ethanol was highly dependent upon both strain and age. Within an inbred strain, adolescent animals were consistently less sensitive to the aversive effects of ethanol than their adult counterparts. However, the dose of ethanol required to produce an aversion response differed as a function of both age and strain.

The meaning of acute kidney injury and its relevance to intensive care and anaesthesia.

Acute kidney injury (AKI) is the new consensus term for acute renal failure. The term describes a continuum of kidney injury, a common condition in the critically ill and after major surgery, which is associated with increased mortality. The incidence of AKI in intensive care unit patients in Australia is >30% and sepsis is a major contributory factor. However, there is limited knowledge about its incidence after major surgery, except for cardiac surgery. The creation of staged AKI classification systems (RIFLE [Risk, Injury, Failure, Loss, End-stage], Acute Kidney Injury Network and the new Kidney Disease: Improving Global Outcomes criteria) has accelerated progress in critical care nephrology research by showing that even small changes in serum creatinine are associated with increased risk of death and that this risk increases progressively with severity of AKI. Recent thought and research has cast doubt over previously accepted pathophysiological views of AKI. Moreover, terms such as 'prerenal azotaemia' and 'acute tubular necrosis' are now being challenged as lacking validity, having little supportive evidence and carrying limited clinical utility. In this review, we explore the limitations of animal and human models of AKI and the implications of recent research on our current understanding of the pathophysiology of AKI. In addition, we describe conventional and novel diagnostic methods and therapies, and explore the clinical implications of the effect of fluid administration and perioperative management. Finally, we identify priorities for clinical investigations and future directions in AKI research.

Erythropoietin as a novel brain and kidney protective agent.

Erythropoietin is a 30.4 kDa glycoprotein produced by the kidney, which is mostly known for its physiological function in regulating red blood cell production in the bone marrow Accumulating evidence, however suggests that erythropoietin has additional organ protective effects, which may specifically be useful in protecting the brain and kidneys from injury. Experimental evidence suggests that these protective mechanisms are multi-factorial in nature and may include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways and promotion of recovery. In this article we review the physiology of erythropoietin, assess previous work that supports the role of erythropoietin as a general tissue protective agent and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on specific laboratory and clinical data that suggest that erythropoietin has a strong brain protective and kidney protective effect. In addition, we comment on the implications of these studies for clinicians at the bedside and for researchers designing controlled trials to further elucidate the true clinical utility of erythropoietin as a neuroprotective and nephroprotective agent. Finally, we describe EPO-TBI, a double-blinded multi-centre randomised controlled trial involving the authors that is being conducted to investigate the organ protective effects of erythropoietin on the brain, and also assesses its effect on the kidneys.

Treatment of visceral leishmaniasis.

The available treatment options for visceral leishmaniasis (VL) have problems relating to efficacy, adverse effects and cost, making treatment a complex issue. We review the evidence relating to the different methods of treatment in relation to - efficacy and toxicity of the drugs in different areas of the world; ability to monitor side effects, length of treatment; ability of patients to pay for and stay safe during treatment, ability of the healthcare services to give intramuscular, intravenous or oral therapy; the sex and child-bearing potential of the patient and the immune status of the patient. The high mortality of untreated/ poorly treated VL infection makes the decisions paramount, but a unified and coordinated response by each area is likely to be more effective and informative to future policies than an ad hoc response. For patients in resource-rich countries, liposomal amphotericin B appears to be the optimal treatment. In South Asia, miltefosine is being used; the combination of single dose liposomal amphotericin B and short course miltefosine looks encouraging but has the problem of potential reproductive toxicities in females. In Africa, the evidence to switch from SSG is not yet compelling. The need to monitor and plan for evolving drug failure, secondary to leishmania parasite resistance, is paramount. With a few drugs the options may be limited; however, we await key ongoing trials in both Africa and India to explore the effects of combination treatment. If safe and reliable combinations are revealed by the ongoing studies, it is far from clear as to whether this will avoid leishmania parasite resistance. The development of new drugs to add to the armamentarium is paramount. Lessons can be learnt from the management of diseases such as tuberculosis and malaria in terms of planning the switch to combination treatment. As important as establishing the best choice for specific antileishmanial agent is ensuring treatment centers, which can best manage the problems encountered during treatment, specifically malnutrition, bleeding, intercurrent infections, drug side effects and detecting and treating underlying immunosuppression.

Preoperative estimated glomerular filtration rate and RIFLE-classified postoperative acute kidney injury predict length of stay post-coronary bypass surgery in an Australian setting.

We investigated the influence of preoperative estimated glomerular filtration rate and postoperative acute kidney injury on outcomes after coronary bypass surgery in a local setting, with the focus on length of stay. A retrospective analysis of prospectively collected data for 3302 consecutive patients who underwent coronary artery bypass graft surgery (June 1997 through to January 2007) at St. Vincent's Public Hospital, Melbourne, was undertaken. Preoperative estimated glomerular filtration rate was calculated and categorised using US National Kidney Foundation cut-offs for chronic kidney disease (normal function; mild, moderate and severe dysfunction). Postoperative acute kidney injury was categorised using serum creatinine RIFLE criteria (no acute kidney injury, risk, injury and failure). Postoperative intensive care and hospital length of stay was determined. The hazard ratios for time to hospital discharge up to one month decreased (indicating a longer length of stay) as severity of preoperative renal dysfunction category increased when compared to those with normal renal function: mild hazard ratio = 1.02 (95% confidence interval: 0.91 to 1.15, P = 0.70), moderate 0.87 (0.76 to 1.00, P = 0.047), severe 0.47 (0.35 to 0.64, P < 0.001). Hazard ratios also decreased as severity of postoperative acute kidney injury category increased, when compared to those with no acute kidney injury: risk 0.67 (0.58 to 0.77, P < 0.001), injury 0.52 (0.41 to 0.65, P < 0.001), failure 0.35 (0.20 to 0.60, P < 0.001). The increasing severity of preoperative renal dysfunction and postoperative acute kidney injury were associated with increased hospital length of stay. This has implications for resource use, informed consent and case selection.

SPAMM, cine phase contrast imaging and fast spin-echo T2-weighted imaging in the study of intracranial cerebrospinal fluid (CSF) flow.

AIM: To compare the qualitative assessment of cerebrospinal fluid (CSF) flow using a SPAMM (spatial modulation of magnetization) technique with cine phase contrast images (cine PC) and fast spin echo (FSE) T2-weighted images. MATERIALS AND METHODS: SPAMM, PC and T2-weighted sequences were performed on 22 occasions in 19 patients. Eleven of the studies were performed following a neuroendoscopic third ventriculostomy (NTV), and in these cases, the success of the NTV was determined by clinical follow-up. Two observers used consensus to grade the presence of CSF flow at nine different sites for each study. RESULTS: At 14 of the 178 matched sites, which could be assessed by both SPAMM and cine PC, SPAMM CSF flow grade was higher than that of cine PC. At a further 14/178 matched sites, the cine PC grade was higher than that of SPAMM. There was definite CSF flow at 113/182 (62%) of all the cine PC sites assessed, and 110/181 (61%) of all SPAMM sites assessed whilst 108/198 (54%) of FSE T2-weighted image sites demonstrated flow voids. Cine PC grades were higher than SPAMM at the cerebral aqueduct (P < 0.05, Wilcoxon sign rank test). Definite CSF flow within the anterior third ventricle was present in 4/5 (SPAMM) and 3/5 (cine PC) successful NTVs, 0/2 (SPAMM and cine PC) unsuccessful NTVs and 1/10 (SPAMM and cine PC) patients without NTV. CONCLUSION: SPAMM provides a comparable assessment of intracranial CSF flow to that of cine phase contrast imaging at all CSF sites except the cerebral aqueduct.

Yield of mammography in selected patients age < or = 30 years.

BACKGROUND: An outcomes analysis study was performed to quantify the benefit of directed diagnostic imaging of selected very young women (defined as < or = 30 years of age) in our population. Summary results are presented. PATIENTS AND METHODS: Women's Imaging Services were queried for studies performed between April 1, 1997 and December 31, 1998 on women < or = 30 years of age. The authors' referral pathway mandates breast examination by a general surgeon or by the head of Women's Imaging before mammography in all such patients. Studies were excluded if there were reviews of scans performed at other sites. The resulting 142 mammograms were evaluated. RESULTS: Ninety percent of the 142 studies were within normal limits. Only 11 mammograms indicated any required action (7.8%), and only 5 of these merited biopsy. All biopsies revealed benign disease. No carcinomas were detected by biopsy or on clinical follow-up in this cohort of women. These values are congruent with the scarce literature on mammography in this population. CONCLUSIONS: The yield of mammography in the age < or = 30 years population is low.

Rectal bleeding after radiation therapy for prostate cancer: endoscopic evaluation.

PURPOSE: To analyze the frequency and clinical importance of proctitis and hematochezia after radiation therapy for prostate cancer. MATERIALS AND METHODS: Of 63 patients with prostate cancer treated with curative intent by a single radiation oncologist between July 1, 1993, and December 31, 1997, 30 were asymptomatic, but 33 had heme-positive digital rectal examination (DRE) results or hematochezia at routine follow-up. Twenty-six of these patients underwent endoscopy of the sigmoid colon or colon for evaluation of these symptoms. Median doses of 60.0 Gy at postoperative radiation therapy and 68.4 Gy at definitive radiation therapy were delivered to four fields daily by using blocking customized on the basis of computed tomographically documented evidence of disease. The Fisher exact test and the Kaplan-Meier method were used to analyze the results. RESULTS: The frequency of rectal bleeding approached 80% at 3 years after radiation therapy in definitively treated patients. Only 14 patients had proctitis: eight as the only sign, and six in association with other disease. Six patients had other disease without proctitis, and four patients had normal examination findings. The frequency of rectal bleeding in the presence of proctitis was similar to that in the presence of other disease (Fisher exact test, P =.68). CONCLUSION: Hematochezia or positive DRE findings are frequent sequelae of definitive radiation therapy for prostate cancer; however, causes other than proctitis are often documented at endoscopy. Symptomatic individuals warrant rigorous evaluation to rule out serious coexistent disease.

Differentiation of bronchogenic carcinoma from postobstructive pneumonitis by magnetic resonance imaging: histopathologic correlation.

Obstructive pneumonitis frequently occurs distal to hilar bronchogenic carcinomas or in lung adjacent to peripheral tumors. The article evaluates the role of MRI in the differentiation of tumor from pneumonitis. Twelve patients underwent MRI of the thorax before surgery. T1-weighted (SE 310/20) and T2-weighted (SE 2000/60-120) images were obtained through the tumor and presumed areas of pneumonitis. Five histologic types of pneumonitis were identified on pathologic examination of the 12 specimens. Cholesterol pneumonitis, found in 7 patients, was the most common type. Organizing pneumonitis, bronchiectasis with mucus plugs, atelectasis, and abscess were found in 3, 4, 2, and 1 patients, respectively. MRI was able to differentiate tumor from pneumonitis in 5 of 6 patients with a hilar mass and in 5 of 6 patients with a peripheral tumor. This was achieved by a visual difference in signal intensity on heavily T2-weighted (SE 2000/120) images. Cholesterol pneumonitis and bronchiectasis with mucus plugs were always hyperintense relative to tumor, and organizing pneumonitis and atelectasis were isointense and indistinguishable from tumor. MRI can differentiate tumor from pneumonitis provided that pneumonitis is of the cholesterol type or if there are mucus plugs in the collapsed lung.

Evaluation of an ibuprofen controlled-release tablet and placebo in postoperative oral surgery pain.

Seventy-four outpatients with postoperative pain after oral surgery were randomly assigned, on a double-blind basis, to receive a single oral dose of a controlled-release tablet (CRT) containing 600 mg ibuprofen, two 600-mg ibuprofen CRTs, or placebo. Using a self-rating record, subjects rated their pain and its relief hourly for 12 hours after medicating. Estimates of total and peak analgesia were derived from these subjective reports. The ibuprofen CRTs (600 and 1200 mg) had manifested an analgesic effect by hour 1 and their efficacy persisted for 12 hours. Comparable effect for the two ibuprofen CRT dosages could suggest a plateau in analgesia at the 600-mg level or a lack of upside assay sensitivity. Duration of effect was longer for the CRTs than we have previously observed with conventional ibuprofen tablets. Adverse effects were transitory and consistent with the known pharmacologic profile of the medication evaluated.

Lateral gaze deficit suggesting multiple sclerosis.

The case of a 26-year-old white man with multiple sclerosis is presented. Although the patient was unaware of his condition, the signs and symptoms that he presented were highly suggestive of multiple sclerosis. The case is unusual in that initial diagnosis was made by a senior dental student in a social rather than a clinical setting and without a presenting complaint by the patient. The significance of a thorough clinical examination and the responsibility of a general practitioner as a primary health provider to be observant of signs of disease such as multiple sclerosis are discussed.