Modelling drivers and distribution of lead and zinc concentrations in soils of an urban catchment (Sydney estuary, Australia).

The human population is increasing globally and land use is changing to accommodate for this growth. Soils within urban areas require closer attention as the higher population density increases the chance of human exposure to urban contaminants. One such example of an urban area undergoing an increase in population density is Sydney, Australia. The city also possesses a notable history of intense industrial activity. By integrating multiple soil surveys and covariates into a linear mixed model, it was possible to determine the main drivers and map the distribution of lead and zinc concentrations within the Sydney estuary catchment. The main drivers as derived from the model included elevation, distance to main roads, main road type, soil landscape, population density (lead only) and land use (zinc only). Lead concentrations predicted using the model exceeded the established guideline value of 300mgkg-1 over a large portion of the study area with concentrations exceeding 1000mgkg-1 in the south of the catchment. Predicted zinc did not exceed the established guideline value of 7400mgkg-1; however concentrations were higher to the south and west of the study area. Unlike many other studies we considered the prediction uncertainty when assessing the contamination risk. Although the predictions indicate contamination over a large area, the broadness of the prediction intervals suggests that in many of these areas we cannot be sure that the site is contaminated. More samples are required to determine the contaminant distribution with greater precision, especially in residential areas where contamination was highest. Managing sources and addressing areas of elevated lead and zinc concentrations in urban areas has the potential to reduce the impact of past human activities and improve the urban environment of the future.

Measuring laboratory-based influenza surveillance capacity: development of the 'International Influenza Laboratory Capacity Review' Tool.

OBJECTIVES: The 2005 International Health Regulations (IHR 2005) emphasized the importance of laboratory capacity to detect emerging diseases including novel influenza viruses. To support IHR 2005 requirements and the need to enhance influenza laboratory surveillance capacity, the Association of Public Health Laboratories (APHL) and the Centers for Disease Control and Prevention (CDC) Influenza Division developed the International Influenza Laboratory Capacity Review (Tool). STUDY DESIGN: Data from 37 assessments were reviewed and analyzed to verify that the quantitative analysis results accurately depicted a laboratory's capacity and capabilities. METHODS: Subject matter experts in influenza and laboratory practice used an iterative approach to develop the Tool incorporating feedback and lessons learnt through piloting and implementation. To systematically analyze assessment data, a quantitative framework for analysis was added to the Tool. RESULTS: The review indicated that changes in scores consistently reflected enhanced or decreased capacity. The review process also validated the utility of adding a quantitative analysis component to the assessments and the benefit of establishing a baseline from which to compare future assessments in a standardized way. CONCLUSIONS: Use of the Tool has provided APHL, CDC and each assessed laboratory with a standardized analysis of the laboratory's capacity. The information generated is used to improve laboratory systems for laboratory testing and enhance influenza surveillance globally. We describe the development of the Tool and lessons learnt.

Community-onset Staphylococcus aureus infections presenting to general practices in South-eastern Australia.

Community-acquired Staphylococcus aureus infections are a public health concern, yet little is known about infections that do not present to hospital. We identified community-onset S. aureus infections via specimens submitted to a community-based pathology service. Referring doctors confirmed eligibility and described infection site, severity and treatment. Isolates were characterized on antibiotic resistance, PFGE, MLST/SCCmec, and Panton-Valentine leukocidin (PVL), representing 106 community-onset infections; 34 non-multiresistant methicillin-resistant S. aureus (nmMRSA) (resistant to <3 non-ß-lactam antibiotics), 15 multiply antibiotic-resistant MRSA (mMRSA) and 57 methicillin-sensitive S. aureus (MSSA). Most (93%) were skin and soft tissue infections. PVL genes were carried by 42% of nmMRSA isolates [95% confidence interval (CI) 26-61] and 15% of MSSA (95% CI 8-28). PVL was associated with infections of the trunk, head or neck (56·4% vs. 24·3%, P=0·005) in younger patients (23 vs. 52 years, P<0·001), and with boils or abscesses (OR 8·67, 95% CI 2·9-26·2), suggesting underlying differences in exposure and/or pathogenesis.

The Interrelationships among albumin, nutrient intake, and inflammation in elderly recuperative care patients.

OBJECTIVES: To examine the interrelationships among low serum albumin, nutritional depletion, and ongoing inflammation in older patients recovering from illness. DESIGN: A prospective cohort study. SETTING: A transitional care unit (TCU) within a Department of Veterans Affairs hospital nursing home care unit. PARTICIPANTS: 275 older veterans (mean age=78.9 ± 7.5y, 99% male) admitted for recuperative care and rehabilitation. MEASUREMENTS: At admission and discharge (median LOS 24d, IQR 16 to 44d), each subject completed a comprehensive standardized evaluation including a nutritional assessment and measurement of serum albumin, C-reactive protein (CRP), interleukin-6 (IL-6) and its soluble receptor, and tumor necrosis factor-alpha (TNF-α) and its soluble receptors (sTNF-RI and II). Complete nutrient intake assessments (calorie counts) were performed daily. RESULTS: Both the discharge albumin and the change in albumin (discharge minus admission) were strongly and inversely correlated with various indicators of inflammation, particularly CRP and IL-6. Change in CRP was the strongest correlate of change in albumin (R2 = 0.21, P<.001) and discharge IL-6 the strongest correlate of discharge albumin (R2 = 0.21, P<.001). Nutrient intake also correlated with albumin and its change, but entered the multivariable models after inflammatory indicators and explained a smaller portion of the variance. Although there were significant interactions between time and both nutrient intake and inflammation, the relative importance of inflammation as a potential determinant of the serum albumin concentration appeared to remain unchanged with longer periods of observation. CONCLUSIONS: Among elderly patients admitted to a TCU, inflammation appears to be a more powerful determinant of albumin and its change during the hospitalization than is nutrient intake. Further study is needed to prove causality and to determine whether the relative importance of inflammation on the albumin concentration diminishes with more prolonged periods of observation.

Pseudomonas aeruginosa bacteremia over a 10-year period: multidrug resistance and outcomes in transplant recipients.

AIM: Transplant recipients are at risk for hospital-acquired infections (HAIs), including those caused by Pseudomonas aeruginosa. Of all HAIs, bloodstream infection (BSI) remains one of the most life-threatening. METHODS: Over a 10-year period, we studied 503 patients, including 149 transplant recipients, with pseudomonal BSI from the University of Pittsburgh Medical Center. Trends in antimicrobial susceptibility, risk factors for multidrug resistance (MDR), and outcomes were compared between transplant and non-transplant patients. RESULTS: Resistance to all antibiotic classes was significantly greater in pseudomonal blood culture isolates from transplant compared with non-transplant patients (P<0.001). Of isolates from transplant recipients (n=207), 43% were MDR, compared with 18% of isolates from non-transplant patients (n=391) (odds ratio [OR] 3.47; 95% confidence interval [CI] 2.34-5.14, P<0.001). Among all patients, independent risk factors for MDR P. aeruginosa BSI included previous transplantation (OR 2.38; 95% CI 1.51-3.76, P<0.001), hospital-acquired BSI (OR 2.41; 95% CI 1.39-4.18, P=0.002), and prior intensive care unit (ICU) admission (OR 2.04; 95% CI 1.15-3.63, P=0.015). Mortality among transplant recipients was 42%, compared with 32% in non-transplant patients (OR 1.55; 95% CI 0.87-2.76, P=0.108). For transplant recipients, onset of BSI in the ICU was the only independent predictor of mortality (OR 8.00; 95% CI 1.71-37.42, P=0.008). CONCLUSIONS: Transplant recipients are at greater risk of MDR P. aeruginosa BSI, with an appreciable mortality. Future management must concentrate on the implementation of effective preventative strategies.

Significant photoreceptor rescue by treatment with a combination of antioxidants in an animal model for retinal degeneration.

The purpose of this study was to investigate the presence of oxidative DNA damage in the photoreceptors of the rd1 mouse, an animal model for retinitis pigmentosa, and to determine if antioxidants could delay the progress of photoreceptor cell death. Retinas of rd1 mice and congenic wild type controls were examined for DNA oxidation and fragmentation. To study the rescue effect of antioxidants on retinal degeneration, rd1 retinas were studied in vitro and in vivo using lutein, zeaxanthin, alpha lipoic acid and reduced l-glutathione. For the in vitro studies, antioxidants were added to the culture medium. For the in vivo studies, postnatal day (PN3) pups of rd1 mice were fed antioxidants either individually or in combination and control rd1 animals received vehicle alone. Histological evaluation was performed using hematoxylin/eosin and avidin staining, as well as terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Many of the rd1 rod photoreceptors at PN11 displayed oxidative DNA damage and TUNEL positive reaction which co-localized in a subset of rod photoreceptors. Avidin-labeled rod photoreceptors were more abundant than the TUNEL positive photoreceptors of the rd1 mouse, indicating that oxidative DNA damage precedes fragmentation. The number of TUNEL positive and avidin positive cells was considerably decreased upon treatment with the combination of the antioxidants. Rescue of rd1 photoreceptors was significant at PN18 and PN17, respectively, in the in vitro and in vivo studies. In conclusion individual antioxidants had no significant rescue effect but the combination slowed down the rd1 rod photoreceptor degeneration, indicating an additive or synergistic effect.

The GAIN (Geriatric Anorexia Nutrition) registry: the impact of appetite and weight on mortality in a long-term care population.

PURPOSE: To investigate nursing home residents at high nutritional risk to determine: 1) which baseline nutrition or health status indicators correlated with subsequent weight gain or appetite improvement; and, 2) whether a continued weight loss correlated with higher mortality. METHODS: At study entry, nutritional, health status, and demographic data were extracted from the nursing home chart or the MDS. Each subject was tracked for 6 months with survival, weight gain of 5%, and appetite improvement the primary outcome measures. RESULTS: During the 6-month study, younger age was the strongest correlate of appetite improvement. The odds of gaining weight were negatively correlated with BMI, age, and feeding dependency. Subjects who were receiving appetite stimulants (orexigenics) at study entry had a 70% greater probability of gaining weight than those who were not. A weight loss during the 6-month period was associated with a nearly two-fold increase in the likelihood of dying (adjusted RR: 1.95, 95% CI 1.43 to 2.66). CONCLUSION: The course of nutritional problems within nursing homes is highly variable. Continued weight loss, however, appears to have ominous implications for mortality. Younger residents who are not dependent on others for feeding assistance, and who receive orexigenics tend to experience weight gain.

Vitamin D receptor null mutant mice fed high levels of calcium are fertile.

Vitamin D receptor (VDR) null mutant mice provide a model to investigate the possible effect of vitamin D on female reproduction. Infertility in these mice has been reported but it is uncertain whether the infertility results from a lack of VDR or from the hypocalcemia that results from a lack of VDR. VDR null mutant mice and wild-type controls were fed a nonpurified, high calcium or medium calcium diet, plus a diet containing lactose and their reproductive efficiency was examined. VDR null mutant mice fed a nonpurified diet were hypocalcemic and were found to be largely infertile with 14% fertility, while the fertility percentage of normocalcemic VDR null mutant mice and wild-type mice was between 86% and 100%. A high calcium or medium calcium diet maintained 100% fertility in the VDR knockout mice; removal of the lactose from this diet did not diminish reproductive capability. Reproductive capacity of VDR null mutant mice was analyzed when they were fed purified diets containing 0.02-2% calcium. Mutant mice fed a low calcium diet (0.47%) had a lower reproductive efficiency than VDR null mutant mice fed a diet that resulted in normal serum calcium concentrations. Thus, high dietary calcium levels are required for normal reproduction in VDR null mutant female mice. It seems that the defect in reproduction reported previously for VDR null mutant mice is not the lack of a direct effect of 1,25-dihydroxycholecalciferol on reproductive function but is the result of hypocalcemia.

Influenza A virus outbreak in a neonatal intensive care unit.

BACKGROUND: Nosocomial infections with influenza virus are rarely recognized in neonatal intensive care units (NICU). An outbreak of influenza A virus infection in the NICU of an urban county hospital during the 1997 to 1998 influenza season is reported. METHODS: Clinical and virologic data were recorded in all symptomatic NICU patients after influenza A infection was diagnosed in one infant in October, 1997. RESULTS: Influenza A/H3N2 was isolated from two of four symptomatic infants. The application of rapid diagnostic techniques for the characterization of influenza virus infection allowed the timely institution of basic infection control measures, limiting this outbreak. Resistance to amantadine was documented for the first time in this patient population by reverse transcription-PCR within 48 h of treatment in one case. CONCLUSIONS: Prevention by immunization is a priority in those caring for high risk NICU patients.

Submaximal exercise testing using lactate threshold and venous oxygen tension as endpoints in normal dogs and in dogs with heart failure.

Twelve normal dogs and 7 dogs with experimentally induced heart failure were chronically instrumented to measure hemodynamic variables and blood gas tensions at rest and during graded treadmill exercise. Three groups of 4 normal dogs each (group 1, 15 to 20 kg; group 2, 21 to 30 kg; group 3, 31 to 40 kg) were exercised on a treadmill at a 16% grade at 1, 2, and 3 miles per hour, and at a 22% and a 26% grade at 3 miles per hour (5 total exercise levels) until blood lactate concentration increased to a value greater than 1 mmol/L. Blood lactate concentration and blood gas tensions were measured 5 and 15 minutes after starting exercise, and cardiac output was measured between 8 and 10 minutes of exercise. Results indicated that the same exercise protocol could be used for dogs ranging in size from 15 to 40 kg. Blood lactate concentration increased in normal dogs at varying workloads, but always at or above a workload of 3 miles per hour at a 16% grade. Dogs with class IV heart failure always experienced an increase in blood lactate concentration when walked at 1 mile per hour at a 16% grade for 5 minutes. A femoral vein PO2 between 21 and 24 mm Hg in normal dogs, and between 16 and 22 mm Hg in dogs with heart failure was always associated with an increase in blood lactate concentration. The primary problem with this exercise protocol was the unwillingness of some dogs to walk on the treadmill during the preselection phase. We conclude that we have devised a submaximal exercise test that can be used to evaluate exercise capability in dogs ranging in size from 15 to 40 kg, that the described exercise protocol can be used to identify decreased flow reserve in dogs with class IV heart failure induced by rapid ventricular pacing, and that either femoral vein oxygen tension or blood lactate concentration can be used as the endpoint for submaximal exercise testing in dogs.

Homogeneous sample preparation of raw shrimp using dry ice.

Sample homogeneity is critical to accurate and reproducible analysis of trace residues in foods. A method of uniform sample preparation using dry ice is described for shrimp. Other sample preparation techniques for raw shrimp produce nonhomogeneous samples. Sample homogeneity was determined through analysis of chloramphenicol added to intact tiger or white shrimp prior to sample preparation. Simulated chloramphenicol residue levels were 50, 15, 10, and 5 ppb. No significant differences were noted when analyses of shrimp inoculated with chlor-amphenicol prior to sample preparation with dry ice were compared with analyses of shrimp spiked after grinding with dry ice. Grinding shrimp with dry ice produced samples with homogeneous chloramphenicol residues. This technique should be applicable to other tissues and vegetable products.

Food technology of the antioxidant nutrients.

The evidence that the antioxidant nutrients (vitamin C, vitamin E, and beta-carotene) may play a much more important role in our health and well being is growing rapidly. The knowledge gained by the nutritionists and biochemists will ultimately require a technical transformation to achieve successful application in foods. The physical and chemical properties of these compounds require specialized forms and techniques that must be matched to the particular food and its method of production. These properties make the application of these nutrients in foods a challenge for the food scientist. This presentation covers the practical aspects of adding these nutrients to various foods and describes some examples of how these nutrients can be applied.

The emerging role of vitamins as antioxidants.

The recommended dietary allowances for vitamins are designed to estimate the levels of intake needed to prevent known deficiency states in most healthy people. Evidence is now accumulating that some vitamins may have health-promoting benefits in amounts higher than the current recommendations. The antioxidant properties of vitamins may play a role in treating or preventing a variety of disorders, including atherosclerosis, age-related cataracts and macular degeneration, and some cancers. This article reviews the possible risks and benefits of high intakes of antioxidant vitamins, including the controversy about supplementation.

Oral nutritional supplement use in elderly nursing home patients.

OBJECTIVES: To determine why elderly nursing home patients receive liquid oral protein supplements, what nutritional assessment is utilized, and whether there is evidence of effectiveness. DESIGN: Retrospective, case control study comparing patients over 65 years of age, at two nursing homes, who were served oral supplements (OS) at least twice daily (n = 56), with a random sample of non-supplemented, non-tube fed patients (n = 53). Comparisons included medical diagnoses, medications, morbidity and mortality, weight changes, laboratory test results, and functional and behavioral status. RESULTS: Nursing home patients were begun on OS (median time after admission = 2 months, range = 0-72 months) primarily because of weight loss (71%) and poor appetite (16%). Supplemented patients were below an age-adjusted body weight on admission, unlike controls, and continued to lose weight until OS were started. On OS, weight was slowly regained over 9-10 months in a majority of patients to approximate admission weight. Some patients on OS showed improvement in albumin, total lymphocyte count, cholesterol, or hemoglobin, but too few patients had sufficient lab tests to verify any consistent effect. Mortality was higher in OS patients (8 vs 2, P = 0.057), who were also somewhat older (87.9 vs 84.5 years), but there was no statistical difference in infection or hospitalization rate. MEASUREMENTS: Nutritional assessment in these nursing homes consisted almost exclusively of (1) serial measurement of weight, (2) comparison of weight to (a) "ideal body weight" and (b) previous weight, and (3) a subjective evaluation of food consumption. No other anthropometric evaluations or laboratory tests were conducted for nutritional assessment. CONCLUSIONS: The diagnosis of and intervention in under-nutrition in nursing home patients is frequently disorganized. In addition, nutritional assessment, either for screening or for following intervention, is hampered by the lack of convenient and unambiguous assessment tools. OS use is associated with weight gain in many nursing home patients and also improves other nutritional parameters in selected individuals.

Right parasternal imaging: an underutilized echocardiographic technique.

If the echocardiographer uses only standard imaging planes, he or she may fail to obtain vital information about the aorta, atrial septum, superior and inferior vena cavae, and the coronary arteries. The evaluation of caval-to-systemic venous atrial connections (Senning or Mustard) in transposition of the great arteries of systemic vena caval or right atrial-to-pulmonary anastomosis (Fontan) in tricuspid atresia and single ventricle may not be adequately seen when only the standard left parasternal, apical, subcostal, and suprasternal imaging planes are used. Therefore, the use of the right parasternal imaging plane may help to provide crucial information regarding these areas when the standard views are unable to delineate them adequately. The right parasternal window is an additional echocardiographic window that should become part of a complete echocardiographic examination.

The acute haemodynamic effects of captopril in dogs with heart failure.

The acute effects of three doses of captopril (12.5, 25, and 50 mg [approximately 0.5, 1.0, and 2.0 mg/kg]) on several haemodynamic variables and plasma aldosterone concentration were investigated in four dogs with experimentally produced heart failure (rapid ventricular pacing) and one dog with dilated cardiomyopathy. Haemodynamic variables were measured with a Swan-Ganz thermodilution catheter and an indwelling carotid artery catheter at baseline and 1, 2, and 4 h after drug administration. A statistically significant (P < 0.05) decrease in peripheral vascular resistance was observed 1 and 2 h following the 12.5 mg dose. A significant and large enough decrease in peripheral vascular resistance to produce a significant decrease in mean systemic arterial blood pressure was observed 1 and 2 h after administering 25 and 50 mg of captopril. A mild but significant increase in cardiac output was observed 1 h after each dose. The drug effect on systemic arterial blood pressure lasted less than 4 h. No statistically significant changes were observed for the group in pulmonary capillary wedge pressure, right atrial blood pressure, or plasma aldosterone concentration at any time. We conclude that the acute haemodynamic benefits provided by captopril administration were mild and due primarily to arteriolar dilation. Doses of approximately 1-2 mg/kg produced slightly greater arteriolar dilation than an approximate dose of 0.5 mg/kg. The drug effect was short-lived, lasting less than 4 h.

The incidence of attempted CPR in nursing homes.

We studied the frequency with which cardiopulmonary resuscitation (CPR) is attempted on residents of American nursing homes. Each author (all members of the Clinical Practice Committee of the American Geriatrics Society) completed a questionnaire in 1989 about policy and practice regarding CPR during 1988 in each of three to seven nursing homes, by questioning the medical or nursing director or the administrator. Because of the vagaries of nursing home record-keeping, data from some homes were allowed when they were "accurate to within 10%." Data from 58 nursing homes, totalling 10,836 bed-years were available. In 33 of these homes, accounting for 5,425 bed-years, CPR was never attempted. CPR was more likely to be foregone in nursing homes with religious affiliation than in nursing homes without (13 of 17 vs 18 of 38; chi 2 = 4.0; P less than 0.05). Religious affiliation was unknown for three nursing homes. Academic affiliation (10 of 16 vs 20 of 37 in non-affiliated nursing homes) and non-profit status (14 of 19 vs 16 of 23 in for-profit nursing homes) did not significantly affect the likelihood that CPR would never be used. In 31 of 54 nursing homes with explicit do not resuscitate (DNR) policies, CPR was never performed, compared to 2 of 4 homes without such policies. For nursing homes with complete data, there were 1,196 deaths in 32 facilities where CPR was never attempted compared to 1,294 deaths for 24 nursing homes with CPR. For 22 nursing homes without CPR, there were 2,172 emergency room transfers compared to 1,363 emergency room transfers in 18 nursing homes where CPR was attempted.(ABSTRACT TRUNCATED AT 250 WORDS)

Hospital admission for xanthine toxicity.

A follow-up study of 35,909 outpatients who filled more than 220,000 prescriptions for theophylline over 9 years revealed 30 hospitalizations for xanthine toxicity. The overall estimated incidence rate of 7.8/10,000 person-years at risk indicates that in this population, hospitalization for xanthine toxicity is a relatively rare event.