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1.
J Pediatr Urol ; 18(2): 171-177, 2022 04.
Article in English | MEDLINE | ID: mdl-35144885

ABSTRACT

BACKGROUND: Use of prophylactic antibiotics after stented hypospadias repair is very common, but most research has not identified any clinical benefits of this practice. Only one study has found that postoperative prophylaxis reduces symptomatic urinary tract infections (UTIs). Data from the same trial suggested that prophylaxis may also reduce urethroplasty complications. No studies on this subject have been placebo-controlled. OBJECTIVE: We performed a randomized, double-blind, placebo-controlled study to evaluate the effect of postoperative prophylactic antibiotics on the incidence of infection or urethroplasty complications after stented repair of midshaft-to-distal hypospadias. STUDY DESIGN: Boys were eligible for this multicenter trial if they had a primary, single-stage repair of mid-to-distal hypospadias with placement of an open-drainage urethral stent for an intended duration of 5-10 days. Participants were randomized in a double-blind fashion to receive oral trimethoprim-sulfamethoxazole or placebo twice daily for 10 days postoperatively. The primary outcome was a composite of symptomatic UTI, surgical site infection (SSI), and urethroplasty complications, including urethrocutaneous fistula, meatal stenosis, and dehiscence. Secondary outcomes included each component of the primary outcome as well as acute adverse drug reactions (ADRs) and C. difficile colitis. RESULTS: Infection or urethroplasty complications occurred in 10 of 45 boys (22%) assigned to receive antibiotic prophylaxis as compared with 5 of 48 (10%) who received placebo (relative risk [RR], 2.1; 95% confidence interval [CI], 0.8 to 5.8; p = 0.16). There were no significant differences between groups in symptomatic UTIs, SSIs, or any urethroplasty complications. Mild ADRs occurred in 3 of 45 boys (7%) assigned to antibiotics as compared with 5 of 48 (10%) given placebo (RR, 0.6; 95% CI, 0.2 to 2.5; p = 0.72). There were no moderate-to-severe ADRs, and no patients developed C. difficile colitis. CONCLUSIONS: In this placebo-controlled trial of 93 patients, prophylactic antibiotics were not found to reduce infection or urethroplasty complications after stented mid-to-distal hypospadias repair. The study did not reach its desired sample size and was therefore underpowered to independently support a conclusion that prophylaxis is not beneficial. However, the result is consistent with most prior research on this subject. GOV IDENTIFIER: NCT02096159.


Subject(s)
Clostridioides difficile , Colitis , Hypospadias , Urinary Tract Infections , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis , Colitis/complications , Colitis/drug therapy , Humans , Hypospadias/complications , Male , Urinary Tract Infections/drug therapy , Urinary Tract Infections/etiology , Urinary Tract Infections/prevention & control
2.
Sci Total Environ ; 671: 215-231, 2019 Jun 25.
Article in English | MEDLINE | ID: mdl-30928751

ABSTRACT

Thermally enriched runoff from urban impervious surfaces can be harmful to aquatic life; however, only limited information is available on how to mitigate these impacts at the watershed-scale. This study evaluates the effects of retrofitting an urban watershed with thermal mitigation practices (TMPs) relative to thermal toxicity thresholds for aquatic species. The Minnesota Urban Heat Export Tool (MINUHET) and Storm Water Management Model (SWMM) models were used to evaluate TMPs that help reduce temperature and total heat loads (THL) from the Stroubles Creek watershed in Blacksburg, Virginia. We used the aquatic health criteria for brook trout (Salvelinus fontinalis), the most sensitive species present downstream of the watershed, as a performance measure. TMPs included bioretention systems, methods for reducing the albedo of surfaces (cool surfaces), and increasing forest canopy. Performance metrics included Event Mean Temperature (EMT), and the Percentage of Time Temperature Exceeded the 21 °C Acute Toxicity Threshold [Percentage of Time above the Threshold (PTAT)] for brook trout; these metrics were used to quantify reductions in heat loads and temperatures. TMPs were evaluated during continuous simulation and selected storm events. Increased forest canopy alone produced the greatest reduction of stream temperature, as quantified by EMT and PTAT metrics during continuous and event-based simulations. In contrast, cool surfaces reduced THL more than any other individual TMP for the continuous simulation. A comprehensive mitigation plan (CMP) integrating all three TMPs reduced THL by 62.3%, and PTAT by approximately 12%, for the entire summer of 2015. The CMP was also applied to select storm events, during which streamflow EMT was reduced up to 9%, and PTAT was reduced nearly to zero. This study, which is the first to simulate watershed-scale TMPs for a large, complex urban area, demonstrates the application of appropriate strategies for restoring aquatic habitats in the thermally impacted Stroubles Creek.


Subject(s)
Environmental Restoration and Remediation/methods , Hot Temperature , Rivers/chemistry , Trout/physiology , Water Pollution/analysis , Animals , Models, Theoretical , Urbanization , Virginia
3.
J Environ Manage ; 226: 457-475, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30145502

ABSTRACT

Urban development increases runoff temperatures from buildings and pavement, which can be harmful to aquatic life. However, our ability to predict runoff temperature as a function of land use is limited. This paper explores available tools for simulating runoff temperature with respect to brook trout (Salvelinus sp.), a sensitive species. The Minnesota Urban Heat Export Tool (MINUHET) and the Storm Water Management Model (SWMM) were applied to a 14.1 km2 portion of the Stroubles Creek watershed near Blacksburg, Virginia for two summers. Streamflow, water temperature, and weather data were acquired from the Virginia Tech StREAM Lab (Stream Research, Education, and Management) monitoring stations. SWMM and MINUHET were calibrated and validated for streamflow, and stream temperature, respectively. The models were sensitive to imperviousness (SWMM-predicted streamflow) and dew point temperature (MINUHET-predicted water temperature). While the models output time-step was 15 min, the model performance in simulating streamflow was evaluated using Nash-Sutcliffe Efficiency (NSE) on hourly time-steps. NSE values were 0.67 and 0.65 for SWMM and 0.62 and 0.57 for MINUHET during the calibration and validation periods, respectively, indicating that SWMM performed better than MINUHET in streamflow simulation. Stream temperatures were simulated using MINUHET with NSE value of 0.58 for the validation period, demonstrating a satisfactory simulation of water temperature. Since SWMM is not capable of stream temperature simulation beyond simple mixing. Hydrologic and thermal outputs from SWMM and MINUHET were combined in a hybrid approach that emphasized the strength of each respective model, i.e. SWMM for runoff and streamflow and MINUHET for water temperature. Heat loads were simulated using the MINUHET and the Hybrid models; the Hybrid model (0.56) had a greater NSE than MINUHET (0.45) alone. MINUHET predictions indicated water temperatures would exceed the trout toxicity threshold of 21 °C during 39% and 38% of calibration and validation periods, respectively. Since the observed temperature exceeded the toxicity threshold 59% and 53% of the time for the calibration and validation periods, respectively, MINUHET was not a conservative predictor of the duration of temperatures exceeding the toxicity threshold value.


Subject(s)
Models, Theoretical , Rivers , Urbanization , Animals , Minnesota , Virginia , Water Movements
4.
Environ Sci Technol ; 52(9): 5358-5366, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29634901

ABSTRACT

Bioretention cells (BRCs) are effective tools for treating urban stormwater, but nitrogen removal by these systems is highly variable. Improvements in nitrogen removal are hampered by a lack of data directly quantifying the abundance or activity of denitrifying microorganisms in BRCs and how they are controlled by original BRC design characteristics. We analyzed denitrifiers in twenty-three BRCs of different designs across three mid-Atlantic states (MD, VA, and NC) by quantifying two bacterial denitrification genes ( nirK and nosZ) and potential enzymatic denitrification rates within the soil medium. Overall, we found that BRC design factors, rather than local environmental variables, had the greatest effects on variation in denitrifier abundance and activity. Specifically, denitrifying populations and denitrification potential increased with organic carbon and inorganic nitrogen concentrations in the soil media and decreased in BRCs planted with grass compared to other types of vegetation. Furthermore, the top layers of BRCs consistently contained greater concentrations and activity of denitrifying bacteria than bottom layers, despite longer periods of saturation and the presence of permanently saturated zones designed to promote denitrification at lower depths. These findings suggest that there is still considerable potential for design improvements when constructing BRCs that could increase denitrification and mitigate nitrogen export to receiving waters.


Subject(s)
Denitrification , Soil Microbiology , Bacteria , Nitrogen , Soil
5.
Sci Total Environ ; 610-611: 1467-1475, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-28892841

ABSTRACT

The past three decades' data on outbreaks in the United States indicate that homes dependent on untreated groundwater (e.g. wells) for household drinking water that are also reliant on onsite treatment of household wastewater (e.g. septic systems) may be at greater risk for waterborne disease. While groundwater quality monitoring to protect public health has traditionally focused on the detection of fecal indicator bacteria, the application of emerging source tracking strategies may offer a more efficient means to identify pollution sources and effective means of remediation. This study compares the movement of common fecal indicator bacteria (E. coli and enterococci) with a chemical (optical brighteners, OB) and a molecular (Bacteroides HF183) source tracking (ST) target in small scale septic drainfield models in order to evaluate their potential utility in groundwater monitoring. Nine PVC column drainfield models received synchronized doses of primary-treated wastewater twice daily, with influent and effluent monitored bi-weekly over a 7-month period for all targets. Results indicate that E. coli and enterococci concentrations were strongly associated (Spearman's rank, p<0.05), and correlations between enterococci and optical brighteners were moderately strong. Bacteroides HF183 was significantly, but not strongly, associated with optical brighteners and both indicator bacteria (Point-biserial correlation, p<0.05), most likely due to its sporadic detection. Application of human ST marker monitoring in groundwaters at risk of contamination by human sewage is recommended, although consistent interpretation of results will rely on more detailed evaluation of HF183 incidence in source contamination waters.


Subject(s)
Environmental Monitoring/methods , Sewage/microbiology , Water Microbiology , Bacteria , Bacteroides , Feces/microbiology , Humans , Waste Disposal, Fluid/methods , Water Pollution
6.
J Environ Qual ; 46(1): 1-9, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28177423

ABSTRACT

The remediation of mine water to preserve receiving water quality has advanced substantially over the past half century, but prospective regulations to limit the conductivity of mining-impacted waters pose a significant new challenge. Conventional approaches to reduce high levels of conductivity in these mine waters are often costly, requiring high levels of maintenance and significant inputs of energy and refined chemicals. In contrast, passive biological treatment (PBT) systems are a relatively low-cost, low-maintenance treatment technology for mine waters that have been used for over three decades. However, their practical ability to reduce conductivity is unclear, given previous research reports focused on the removal of metals, acidity, and solids. A systematic literature review to identify previous reports of PBT systems at the laboratory or field scale that include evaluations of changes in conductivity suggests that decreases in conductivity of 30 to 40% are achievable. Substantial variability in performance is common, however, and conductivity increased markedly in some systems. This variation may be associated with the dissolution of limestone, which is a key treatment material in some systems. Although the development of PBT to serve as pre-, post-, or stand-alone treatment systems targeting conductivity may reduce overall treatment cost in some settings, optimization of these designs requires an increase in the number of published conductivity datasets from similar systems, detailed reports on the key ions contributing to elevated conductivity region to region, and further investigation of the underlying biochemical processes responsible for conductivity reductions.


Subject(s)
Mining , Water Pollutants, Chemical , Water Purification , Metals , Prospective Studies , Review Literature as Topic
7.
Ecology ; 97(1): 17-24, 2016 Jan.
Article in English | MEDLINE | ID: mdl-27008770

ABSTRACT

It has been proposed that plant biodiversity may increase the erosion resistance of soils, yet direct evidence for any such relationship is lacking. We conducted a mesocosm experiment with eight species of riparian herbaceous plants, and found evidence that plant biodiversity significantly reduced fluvial erosion rates, with the eight-species polyculture decreasing erosion by 23% relative to monocultures. Species richness effects were largest at low levels of species richness, with little increase between four and eight species. Our results suggest that plant biodiversity reduced erosion rates indirectly through positive effects on root length and number of root tips, and that interactions between legumes and non-legumes were particularly important in producing biodiversity effects. Presumably, legumes increased root production of non-legumes by increasing soil nitrogen availability due to their ability to fix atmospheric nitrogen. Our data suggest that a restoration project using species from different functional groups might provide the best insurance to maintain long-term erosion resistance.


Subject(s)
Environmental Monitoring/methods , Geological Phenomena , Plants/classification , Water Movements , Biodiversity , Logistic Models , Models, Biological , Population Dynamics , Soil , Species Specificity
8.
Environ Manage ; 52(4): 861-76, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23925899

ABSTRACT

We studied stormwater detention basins where woody vegetation removal was suspended for 2 years in Virginia, USA to determine if woody vegetation can control Typha populations and how early woody plant succession interacts with Typha, other herbaceous vegetation, and site factors. Distribution and composition of woody vegetation, Typha and non-Typha herbaceous vegetation biomass, and site factors were assessed at 100 plots in four basins ranging in age from 7 to 17 years. A greenhouse study examined the interaction of shade and soil moisture on Typha biomass and persistence. Principal component analysis identified an environmental gradient associated with greater water table depths and decreased elevation that favored Typha but negatively influenced woody vegetation. Elevation was correlated with litter layer distribution, suggesting that initial topography influences subsequent environmental characteristics and thus plant communities. Soil organic matter at 0-10 cm ranged from 5.4 to 12.7%. Woody plants present were native species with the exception of Ailanthus altissima and Pyrus calleryana. In the greenhouse, shade and reduced soil moisture decreased Typha biomass and rhizome length. The shade effect was strongest in flooded plants and the soil moisture effect was strongest for plants in full sun. Typha in dry soil and heavy shade had 95% less total biomass and 83% smaller rhizomes than Typha in flooded soil and full sun, but even moderate soil moisture reductions decreased above- and below-ground biomass by 63 and 56%, respectively. Suspending maintenance allows restoration of woody vegetation dominated by native species and may suppress Typha invasion.


Subject(s)
Biomass , Trees , Typhaceae/growth & development , Chlorophyll/analysis , Drainage, Sanitary , Plant Shoots/growth & development , Soil
10.
Nat Clin Pract Cardiovasc Med ; 5(7): 387-95, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18521110

ABSTRACT

Heart disease presentation can differ between the sexes because nonobstructive coronary disease and angina unrelated to exercise are considerably more prevalent in women than in men. When the outcomes of large, randomized, controlled trials failed to demonstrate cardiac risk protection, many women and their physicians abandoned hormone replacement therapy as primary or secondary prevention for cardiovascular disease. We are concerned that the apparent blanket condemnation of steroids has not sufficiently distinguished between the cardiovascular actions of estrogen, progesterone and the synthetic progestin medroxyprogesterone acetate. The actions of active metabolites of progestins are not well understood and in some cases have not been explored. We intend to present what is known and what is not known about progesterone per se versus medroxyprogesterone acetate, particularly with regard to cardiovascular effects. This Review considers the mounting evidence that progesterone improves cardiovascular function and proposes its mechanism of action-restoration of a threshold level of progesterone as preventive of microvascular cardiac ischemia-and compares oral and transdermal routes of administration. We hope to stimulate research to determine whether progesterone, with or without estrogen, has a role in reducing cardiovascular risk and treating cardiovascular disease including myocardial ischemia in postmenopausal women.


Subject(s)
Cardiovascular Diseases/prevention & control , Estrogen Replacement Therapy , Medroxyprogesterone Acetate/administration & dosage , Progesterone/administration & dosage , Animals , Estrogens/pharmacology , Female , Humans , Medroxyprogesterone Acetate/therapeutic use , Postmenopause , Progesterone/therapeutic use , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome
12.
Soc Sci Med ; 63(6): 1454-65, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16765496

ABSTRACT

Low-wage workers represent an ever-increasing proportion of the US workforce. A wide spectrum of firms demand low-wage workers, yet just 10 industries account for 70% of all low-paying jobs. The bulk of these jobs are in the services and retail sales industries. In health services, 60% of all workers are low-paid, with nursing aides, orderlies, personal attendants, and home care aides earning an average hourly wage of just 7.97 US dollars--a wage that keeps many of these workers hovering near or below the poverty line. Nursing assistants also tend to work in hazardous and grueling conditions. Work conditions are an important determinant of psychological well-being and mental disorders, particularly depression, in the workplace have important consequences for quality of life, worker productivity, and the utilization and cost of health care. In empirical studies of low-wage workers, county-level variables are of theoretical significance. Multilevel studies have recently provided evidence of a link between county-level variables and poor mental health among low-wage workers. To date, however, no studies have simultaneously considered the effect of county-and workplace-level variables. This study uses a repeated measures design and multilevel modeling to simultaneously test the effect of county-, organizational-, workplace-, and individual-level variables on depression symptoms among low-income nursing assistants employed in US nursing homes. We find that age and emotional strain have a statistically significant association with depression symptoms in this population, yet when controlling for county-level variables of poverty, the organizational-level variables used were no longer statistically significant predictors of depression symptoms. This study also contributes to current research methodology in the field of occupational health by using a cross-classified multilevel model to explicitly account for all variations in this three-level data structure, modeling and testing cross-classifications between nursing homes and counties of residence.


Subject(s)
Depression/epidemiology , Models, Statistical , Nursing Assistants , Adult , Age Factors , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Nursing Homes , Residence Characteristics , Salaries and Fringe Benefits , Stress, Psychological/epidemiology , Surveys and Questionnaires , United States/epidemiology
13.
Health Place ; 12(4): 688-700, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16318920

ABSTRACT

UNLABELLED: This study simultaneously tests the effect of county, organizational, workplace, and individual level variables on depressive disorders among low-income nursing assistants employed in US nursing homes. A total of 482 observations are used from two waves of survey data collection, with an average two-year interval between initial and follow-up surveys. The overall response rate was 62 percent. The hierarchically structured data was analyzed using multilevel modeling to account for cross-classifications across levels of data. Nursing assistants working in nursing homes covered by a single union in three states were asked about aspects of their working conditions, job stress, physical and mental health status, individual and family health-care needs, household economics and household strain. PARTICIPANTS: The 241 nursing assistants who participated in this study were employed in 34 nursing homes and lived in 49 counties of West Virginia, Ohio and Kentucky. MAIN RESULTS: The study finds that emotional strain, related to providing direct care to elderly and disabled clients, is associated with depressive disorder, as is nursing home ownership type (for-profit versus not-for-profit). However, when controlling for county level socioeconomic variables (Gini index and proportion of African Americans living in the county), neither workplace nor organizational level variables were found to be statistically significant associated with depressive disorder. CONCLUSIONS: This study supports previous findings that emotional demand in health-care environments is an important correlate of mental health. It also adds empirical evidence to support a link between financial strain and depression in US women. While this study does not find that lack of a seniority wage benefits--a factor that can conceivably exacerbate financial strain over time--is associated with depressive disorder among low-income health-care workers, it does find county level measures of poverty to be statistically significant predictors of depressive disorder. Longitudinal county level measures of low-income as predictors of depression may even offer a methodological advantage in that they are presumably more stable indicators of cumulative exposure of low income than are more transient workplace indicators. Incorporating measures of cumulative exposure to low income into empirical studies would be particularly timely given the global changes that are currently restructuring the labor force and influencing work organization and labor processes--most notably the growth in low income jobs and the deskilling of labor. Though this study provides evidence that workplace and organizational level variables are associated with depressive disorder among low-wage nursing assistants in US nursing homes, the fact that these relationships do not hold once county level measures of poverty are controlled for, suggests that more distal upstream determinants of workplace mental health problems, such economic inequality, may be at play in determining the mental health of low wage workers.


Subject(s)
Depression , Health Personnel/psychology , Nursing Homes/organization & administration , Poverty , Adult , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , United States
14.
Psychol Rep ; 95(1): 304-10, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15460385

ABSTRACT

The present study assessed consistency of recollections of personal circumstances of the 9/11 World Trade Center attack and events of the day before (9/10), and the day after (9/12), in a sample of 100 New York City college students. The day before 9/11 represented an ordinary event. A questionnaire was administered twice, 1 wk. and 1 yr. after the 9/11 attack. Students were asked to describe their personal circumstances when hearing about the news of the World Trade Center attack and for the same time of day for 9/10 and 9/12. 18 students returned the follow-up questionnaire. Consistency of initial and follow-up responses for the central categories for both 9/11 and 9/12 of where, who, and activity was very high (9/11: "Where"--100%, "Who"--100%, "What"--94%; 9/12: "Where"--100%, "Who"--100%, "What"--80%). Recollections of 9/10 were significantly less consistent ("Where"--79%, "Who"--71%, "What"--71%). Analysis indicated that students formed vivid, consistent recollections during the events of both 9/11 and 9/12. It is likely that the events of 9/12 also became flashbulb memories, vivid recollections of traumatic events, because the emotional impact of the stressful events, i.e., police and military presence, disrupted schedules, relating to the 9/11 attack endured beyond the day of the attack.


Subject(s)
Awareness , Life Change Events , Mental Recall , September 11 Terrorist Attacks/psychology , Urban Population , Adolescent , Adult , Female , Follow-Up Studies , Humans , Male , New York City , Retention, Psychology , Students/psychology , Surveys and Questionnaires
15.
Int J Health Serv ; 34(3): 415-33, 2004.
Article in English | MEDLINE | ID: mdl-15346678

ABSTRACT

Cost containment has captured the attention of health policymakers in most OECD countries, and deliberations about creating powerful financial incentives dominate health care politics. Some European health systems are now implementing hospital payment schemes that mirror the U.S. model of diagnosis-related groups (DRGs) and are raising premiums and copayment levels in an effort to limit public expenditures. Though financial incentives may indeed help rein in health expenditures, focusing predominantly on financial incentives hinders due consideration of needed structural reforms that improve the continuity, quality, and appropriateness of health care service delivery. This article focuses on the structural specifics of two legally enacted health insurance systems (Germany and Austria) and two national health systems (Great Britain and Denmark) to discuss the influence of structural characteristics on cost-containment efforts. Structural reform strategies discussed include increasing reliance on general practitioners, improving coordination of community and hospital-based specialty care, addressing the stark divide between ambulatory and hospital-based care that exists in some European health systems, and improving continuity of care by better integrating medical and social care sectors. Also discussed is the relative focus on financial incentives versus structural deficits in recent European-health care reform strategies.


Subject(s)
Health Care Costs , Health Care Reform/organization & administration , National Health Programs/organization & administration , Ambulatory Care/economics , Continuity of Patient Care , Cost Control/economics , Cost Control/methods , Efficiency, Organizational , Europe , Gatekeeping , Health Care Reform/economics , Health Personnel/economics , Hospitalization/economics , National Health Programs/economics , Physician-Patient Relations
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