Cellulose Fibre Degradation in Cellulose/Steel Hybrid Geotextiles under Outdoor Weathering Conditions.

Risks from rockfall and land sliding can be controlled by high-tensile steel nets and meshes which stabilise critical areas. In many cases, a recultivation of the land is also desired. However, high-tensile steel meshes alone are not always sufficient, depending on the location and the inclination of the stabilised slope, to achieve rapid greening. Cellulose fibres exhibit high water binding capacity which supports plant growth. In this work, a hybrid structure consisting of a nonwoven cellulose fibre web and a steel mesh was produced and tested under outdoor conditions over a period of 61 weeks. The cellulose fibres are intended to support plant growth and soil fixation, and thus the biodegradation of the structure is highly relevant, as these fibres will become part of the soil and must be biodegradable. The biodegradation of the cellulose fibres over the period of outdoor testing was monitored by microscopy and analytical methods. The enzymatic degradation of the cellulose fibres led to a reduction in the average degree of polymerisation and also a reduction in the moisture content, as polymer chain hydrolysis occurs more rapidly in the amorphous regions of the fibres. FTIR analysis and determination of carboxylic group content did not indicate substantial changes in the remaining parts of the cellulose fibre. Plant growth covered geotextiles almost completely during the period of testing, which demonstrated their good compatibility with the greening process. Over the total period of 61 weeks, the residual parts of the biodegradable cellulose web merged with the soil beneath and growing plants. This indicates the potential of such hybrid concepts to contribute a positive effect in greening barren and stony land, in addition to the stabilising function of the steel net.

Evaluating a school-based science program that teaches the physiological effects of nicotine.

School-based drug prevention programs represent a widely endorsed public health goal, with an important aspect of knowledge-based curricula being education about the physiological effects of drugs. Nicotine is one of the world's most addictive substances and in this program we have used nicotine-induced mammalian-like behaviors in flatworms called planarians to successfully teach students (4th-12th grade; n = 1,616 students) about the physiological and addictive effects of nicotine. An initial study tested the change in knowledge about addictive substances in 6th-12th grade students after they completed a lab examining the effects of two concentrations of nicotine on the number of stereotypies (C-shaped spasms) planarians demonstrate in a 5-minute period of time. Lab discussion focused on developing and testing hypotheses, measurement reliability, and mechanisms of nicotine action. Surveys given pre- and post-lab experience showed that 6th grade students have significantly lower knowledge about nicotine than 7th-12th grade students (6th grade: 40.65 ± 0.78% correct, 7th-12th grade: 59.29 ± 1.71%, p < 0.001) pre-lab, but that students in all grades showed a significant increase in knowledge post-lab (p < 0.001). In 6th grade the lab was effective in improving knowledge about nicotine in urban, suburban and rural schools, p < 0.001, with students in suburban schools showing significantly greater knowledge both pre-test (urban: 37.62 ± 1.45%; suburban: 48.78 ± 1.62%; rural: 37.33 ± 0.99%; p < 0.001) and post-test (urban:60.60 ± 1.85%; suburban: 67.54 ± 1.82%; urban: 61.66 ± 1.18%; p < 0.001). A second study, modifying the lab so that the time spent observing the planarians is reduced to a 1-minute period, showed that students in both 4th and 5th grades had a significant increase in knowledge about the physiological and addictive effects of nicotine post-lab (p < 0.001).

Cost analysis of strategies to reduce blood culture contamination in the emergency department: sterile collection kits and phlebotomy teams.

OBJECTIVE: Blood culture collection practices that reduce contamination, such as sterile blood culture collection kits and phlebotomy teams, increase up-front costs for collecting cultures but may lead to net savings by eliminating downstream costs associated with contamination. The study objective was to compare overall hospital costs associated with 3 collection strategies: usual care, sterile kits, and phlebotomy teams. DESIGN: Cost analysis. SETTING: This analysis was conducted from the perspective of a hospital leadership team selecting a blood culture collection strategy for an adult emergency department (ED) with 8,000 cultures drawn annually. METHODS: Total hospital costs associated with 3 strategies were compared: (1) usual care, with nurses collecting cultures without a standardized protocol; (2) sterile kits, with nurses using a dedicated sterile collection kit; and (3) phlebotomy teams, with cultures collected by laboratory-based phlebotomists. In the base case, contamination rates associated with usual care, sterile kits, and phlebotomy teams were assumed to be 4.34%, 1.68%, and 1.10%, respectively. Total hospital costs included costs of collecting cultures and hospitalization costs according to culture results (negative, true positive, and contaminated). RESULTS: Compared with usual care, annual net savings using the sterile kit and phlebotomy team strategies were $483,219 and $288,980, respectively. Both strategies remained less costly than usual care across a broad range of sensitivity analyses. CONCLUSIONS: EDs with high blood culture contamination rates should strongly consider evidence-based strategies to reduce contamination. In addition to improving quality, implementing a sterile collection kit or phlebotomy team strategy is likely to result in net cost savings.

Reducing blood culture contamination in community hospital emergency departments: a multicenter evaluation of a quality improvement intervention.

OBJECTIVES: Blood culture contamination is a common and preventable problem in the emergency department (ED). In a previous single-center study, changing the process of ED blood culture collection from the traditional "clean," nonsterile procedure to a fully sterile procedure with standardized use of sterile gloves, large-volume chlorhexidine skin antisepsis, and fenestrated sterile drapes resulted in a substantial reduction in contamination. The objective of the current study was to evaluate the effectiveness of this sterile blood culture collection process for reducing blood culture contamination in two community hospital EDs. METHODS: The authors implemented the sterile blood culture collection process in the ED of two hospitals, including Hospital A, which historically had a contamination rate of approximately 5%, and Hospital B, with a 2.5% historical contamination rate. With an interrupted times-series design and segmented regression analysis to adjust for secular trends and autocorrelation, the monthly percentages of cultures contaminated at each hospital during an intervention period (sterile technique) were compared to a 10-month baseline period immediately preceding implementation (clean technique). At Hospital A, the full sterile blood culture collection process was used throughout the 16-month intervention period. At Hospital B, user feedback indicated poor adherence to the process due to difficulty implementing the fenestrated drape component; therefore, the process was simplified to the modified sterile collection process, in which the fenestrated drape component was dropped and sterile gloves and large-volume skin antisepsis were emphasized. Hence, at Hospital B, two intervention periods were compared to the baseline period: the 8-month intervention period 1 (full sterile process) and the subsequent 8-month intervention period 2 (modified sterile process). RESULTS: At Hospital A, during the baseline period, 165 of 3,417 (4.83%) cultures were contaminated, while 142 of 5,238 (2.71%) were contaminated during the intervention period (p < 0.01). In the segmented regression model, the full sterile blood culture collection process was associated with an immediate 2.68% (95% confidence interval [CI] = 1.43% to 3.52%) absolute reduction in contamination and sustained reductions during the entire intervention period. At Hospital B, during the baseline, 63 of 2,509 (2.51%) cultures were contaminated. In intervention period 1 with the full sterile process, 51 of 1,865 (2.73%) cultures were contaminated (p = 0.65), with segmented regression results showing no changes compared to baseline. After simplification of the process to address poor adherence, the modified sterile process during intervention period 2 was associated with a significant reduction in contamination, with 17 of 1,860 (0.91%) cultures contaminated (p < 0.01 compared to baseline). The segmented regression model demonstrated the modified sterile process was associated with an immediate 1.53% (95% CI = 1.00% to 1.88%) absolute reduction in contamination with significant sustained reductions. CONCLUSIONS: Changing the method of blood culture collection from the commonly used nonsterile technique to a sterile process resulted in significant reductions in blood culture contamination at two community hospital EDs, including one with low baseline contamination. Monitoring the implementation process at both sites was important to identify and overcome operational challenges. At one study site, simplification of the process by removing the fenestrated drape component was a key for successful implementation.

Relation of platelet C4d with all-cause mortality and ischemic stroke in patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with significant morbidity, including premature cardiovascular disease, and mortality. Platelets bearing complement protein C4d (P-C4d) were initially determined to be specific for diagnosis of SLE and were later found to be associated with acute ischemic stroke in non-SLE patients. P-C4d may identify a subset of SLE patients with a worse clinical prognosis. This study investigated the associations of P-C4d with all-cause mortality and vascular events in a lupus cohort. A cohort of 356 consecutive patients with SLE was followed from 2001 to 2009. Primary outcome was all-cause mortality. Secondary outcomes were vascular events (myocardial infarction, coronary artery bypass graft, percutaneous coronary transluminal angioplasty, ischemic stroke, venous thromboembolism, pulmonary embolism, or other thrombosis). P-C4d was measured at study baseline. Seventy SLE patients (19.7%) had P-C4d. Mean follow-up was 4.7 years. All-cause mortality was 4%. P-C4d was associated with all-cause mortality (hazard ratio 7.52, 95% confidence interval (CI) 2.14-26.45, p = 0.002) after adjusting for age, ethnicity, sex, cancer, and anticoagulant use. Vascular event rate was 21.6%. Patients with positive P-C4d were more likely to have had vascular events compared to those with negative P-C4d (35.7 vs. 18.2%, p = 0.001). Specifically, P-C4d was associated with ischemic stroke (odds ratio 4.54, 95% CI 1.63-12.69, p = 0.004) after adjusting for age, ethnicity, and antiphospholipid antibodies. Platelet-C4d is associated with all-cause mortality and stroke in SLE patients. P-C4d may be a prognostic biomarker as well as a pathogenic clue that links platelets, complement activation, and thrombosis.

Platelet C4d is associated with acute ischemic stroke and stroke severity.

BACKGROUND AND PURPOSE: Platelets bearing complement C4d were recently reported to be 99% specific for a diagnosis of systemic lupus erythematosus (SLE) and associated with neuropsychiatric lupus. We compared the prevalence of platelet C4d and investigated the clinical associations of platelet C4d in patients with acute ischemic stroke. METHODS: We recruited 80 patients hospitalized for acute ischemic stroke. Stroke severity was measured by the National Institutes of Health Stroke Scale (NIH-SS). Infarct volume was determined by MRI. Platelet C4d was measured by flow cytometry. RESULTS: Mean age was 57.9 years (range: 24.6 to 86.8 years), 58% were male, and 91% were white. Eight patients (10%) with acute ischemic stroke were platelet C4d-positive, which was significantly higher in prevalence compared to healthy controls (0%, P<0.0001) and non-SLE patients with immune/inflammatory disease (2%, P=0.004). The median NIH-SS score and infarct volume for acute stroke patients were 6 (interquartile range [IQR]: 2 to 13) and 3.4 cc (IQR: 1.1 to 16.6), respectively. Platelet C4d-positive patients were more likely to have a severe stroke compared to those with negative platelet C4d (NIH-SS median: 17.5 versus 5, P=0.003). Positive platelet C4d was independently associated with stroke severity (P=0.03) after controlling for age, anticardiolipin antibody (aCL) status, and total anterior circulation of stroke involvement, and also with infarct volume (P=0.005) after controlling for age, aCL status, and old stroke by MRI. CONCLUSIONS: Platelet C4d is associated with severe acute ischemic stroke. Platelet C4d may be a biomarker as well as pathogenic clue that links cerebrovascular inflammation and thrombosis.

Potentially violent disagreements and parenting stress among American Indian/Alaska Native families: analysis across seven states.

OBJECTIVES: We examined the prevalence and correlates of potentially violent disagreements among AI/AN families with children. METHODS: We conducted a cross-sectional examination of data from the 2003 National Survey of Children's Health, limited to seven states for which AI/AN race/ethnicity was available in public use files (Alaska, Arizona, Montana, New Mexico, North Dakota, Oklahoma, and South Dakota). Disagreements were classified based on how the family deals with conflict. If disagreements involved actual (hitting) or symbolic (throwing) violence, even rarely, the household was categorized as having "potentially violent disagreements," with heated argument and shouting being classified as "heated disagreement." Parenting stress and demographic characteristics were included as potential correlates. RESULTS: Potentially violent disagreements were reported by 8.4% of AI/AN and 8.4% of white families. The odds for potentially violent disagreements were markedly higher among parents reporting high parenting stress, in both AI/AN (OR 7.20; CI 3.45-15.00) and white (3.59, CI 2.71-4.75) families. High parenting stress had similar effects on the odds for heated discussion. Having a child with special health care needs was associated with parenting stress. CONCLUSIONS: Questions about disagreement style may be useful as potential screens for domestic violence.

Urinary incontinence in the nursing home: resident characteristics and prevalence of drug treatment.

OBJECTIVES: To provide a descriptive overview of the elderly, nursing home patient population with urinary incontinence (UI). METHODS: This study was a descriptive, cross-sectional database analysis (2002-2003) examining UI prevalence, demographic and clinical characteristics of UI patients, and UI pharmacotherapy prevalence in the nursing home setting. RESULTS: Of the 29 645 eligible subjects, 8995 experienced some level of UI at the time the minimum data set (MDS) was completed (30%). Compared with continent residents, a greater percentage of incontinent residents were older, white women and had a longer length of stay. Incontinent residents also had more indicators of frailty than those who were continent; they were more impaired on activities of daily living and cognitive performance scale scores, were hospitalized more frequently, and had more urinary tract infections, pressure ulcers, and depression. More incontinent residents were using pads/briefs and had bladder retraining and scheduled toileting. Only 8.7% of those residents rated as having the most severe level of incontinence (MDS level 4) were being treated with pharmacotherapy. Of the 8995 residents with a UI rating of 1 to 4, only 8% (n = 731) had pharmacotherapy. CONCLUSION: There is a high prevalence of UI among nursing home residents and having this condition is negatively correlated with measures of resident health status and healthcare utilization. A variety of interventions are used in this setting to treat UI, and use of pharmacologic therapy appears to be quite low. Appropriate use of interventional strategies that may include drug treatment for UI in the nursing home may reduce the substantial personal and cost burdens associated with this condition. However, clinicians may need population-specific scientific evidence in determining which nursing home patients will benefit most from pharmacotherapy.

Detection of prostate cancer with a blood-based assay for early prostate cancer antigen.

Prostate-specific antigen lacks specificity for prostate cancer, so the identification and characterization of a unique blood-based marker for the disease would provide for a more accurate diagnosis, reducing both unnecessary biopsies and patient uncertainty. We previously identified a novel biomarker for prostate cancer, early prostate cancer antigen (EPCA). EPCA antibodies positively stained the negative biopsies of men who, as much as 5 years later, were diagnosed with prostate cancer. The goal of this study was to determine whether EPCA antibodies could be used in a clinically applicable plasma-based immunoassay to specifically detect prostate cancer. Using an EPCA-based ELISA, the protein was measured in the plasma of 46 individuals, including prostate cancer patients, healthy individuals, other cancer patients, spinal cord injury victims, and patients with prostatitis. With a predetermined cutoff value of 1.7 absorbance at 450 nm, only the prostate cancer population, as a whole, expressed plasma-EPCA levels above the cutoff. Statistical analysis showed a significant difference in EPCA levels between the prostate cancer population and each of the other groups, specifically the healthy donors (P < 0.0001), bladder cancer patients (P = 0.03), and spinal cord injury patients (P = 0.001). Sensitivity of the EPCA assay for prostate cancer patients was 92% whereas the overall specificity was 94%. Specificity for the healthy donors was 100%. Although larger trials are required, this initial study shows the potential of EPCA to serve as a highly specific blood-based marker for prostate cancer. EPCA, when coupled with prostate-specific antigen, may help reduce the number of both unnecessary biopsies and undetected prostate tumors.

The effect of acid treatment on survival and protein expression of a laboratory K-12 strain Escherichia coli.

Pre-exposure of log phase enteric bacteria to nonlethal acidic pH induces phenotypic changes that protect the organisms against subsequent lethal acidity. Studies have revealed that when Salmonella typhimurium is grown in minimal medium at pH 5.5 and 4.3 the organism develops a biphasic acid tolerance. This two-stage response has not been reported at present in Escherichia coli; rather it is thought that when this organism is grown in rich medium there is a single stress response throughout the pH range of 4 to 6. We believe that the evidence for such a report is lacking; therefore, in this study the acid response of log phase E. coli was examined in rich medium (LB). The pH 3.0 acid survival assays of a laboratory strain of E. coli K-12 MG1655, after cultures had been exposed to LB acidified to pH 5.5 or pH 4.3 indicate that like S. typhimurium, E. coli shows both an acid tolerance and an acid-shock response to pH 5.5 and 4.3 exposure, respectively. It was consistently found, however, that longer pre-exposure (60 min rather than 15 min) at either pH afforded better protection against the lethal pH 3.0 challenge. Analysis of polypeptide induction at pH 5.5 and 4.3 by two-dimensional gel electrophoresis clearly shows different profiles. Together the results show that in E. coli, pre-treatment between pH 4 and 6 does not result in a flat protective response.