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We studied the response of Brachionus patulus to different concentrations of the heavy metal Pb in the presence and absence of sediments. We conducted acute (LC50) and chronic (life table demography and population growth) toxicity tests using sediment levels of 0, 30 and 280 mg l−1 (=0, 17 and 170 NTU) and Pb at 0, 0.06 and 0.6 mg l−1. Experiments were conducted at 20 ± 1°C on a horizontal shaker and algal food ( Chlorella vulgaris) was added at a density of 1.0 × 106 cells ml−1. The median lethal concentration (LC50 ± 95% Confidence intervals) of PbCl2 for B. patulus was 6.15 ± 1.08 mg l−1. Age-specific survivorship and fecundity curves showed increase in turbidity level resulted in decreased survival and offspring production of the rotifers. Increase in Pb concentration too had a negative effect on the survival and reproductive output of B. patulus. Statistically, average lifespan, life expectancy at birth, gross and net reproductive rates and the rate of population increase were all significantly influenced by the concentration of Pb, turbidity level as well as the interaction of Pb concentration × turbidity level. Rotifers exposed to 170 NTU did not grow regardless of the heavy metal concentration in the medium. Similarly, B. patulus exposed to 0.6 mg l−1 Pb did not survive beyond 10 days regardless of the turbidity level in the medium. The rate of population increase of B. patulus derived from the growth experiments was negative in all treatments containing Pb as low as 0.06 mg l−1 or turbidity level as low as 17 NTU. In treatments containing Pb or sediments, there existed no relation between the egg ratio and the population density. [ABSTRACT FROM AUTHOR]

In this work we evaluated the effect of temperature (22° and 27°C), algal density (Chlorella vulgaris 0.5 × 106 and 2.0 × 106 cells/mL) and different combinations of 2 heavy metals (Zn at 25.25-101.0 μ g/L and Cu at 17.75-71.0 μ g/L) on the population level variables of Moina macrocopa. Median lethal concentration (24 h bioassay at 1 × 106 cells/mL of algal diet) of Zn and Cu for M. macrocopa were 1010 μ g/L and 710 μ g/L, respectively. In the survivorship curves at 27°C there was a reduction in the survival of cladocerans exposed to Cu compared to controls or Zn. The fecundity curves (mx) indicated a steady reproductive output throughout the life span of M. macrocopa, but the negative impact of copper was more than that of zinc. Reproductive phase of M. macrocopa was longer at 22°C than at 27°C. The average lifespan was higher at 22°C and at the higher food level. It was significantly affected by temperature, food level and toxicant concentration, as well as their interaction. The net reproductive rate was also influenced by food and temperature but not by the toxicant level. The generation time ranged between 4-8 days and was lower at 27°C. The population growth rate (r) derived from life table experiments varied from 0.6 to 0.9 per day, depending on the treatment. Regardless of the toxicant level, at 22°C, the population growth was higher at the higher food level. In treatments containing only Cu, the population growth of M. macrocopa was lower than when present together with Zn. Peak population densities of around 30 ind./mL were reached under high food conditions. Higher temperature and lower food level had an adverse effect on M. macrocopa in treatments containing only Cu. In the presence of higher food density, the adverse impact of copper was not evident. The r derived from growth study ranged from 0.25 to 0.64 per day depending on the test conditions. Data were interpreted in terms of sensitivity M. macrocopa for its possible use as a complement, but not as an alternative to Daphnia magna for evaluating the toxicity of heavy metals. [ABSTRACT FROM AUTHOR]

BACKGROUND Between 1999 and 2009 in the United Kingdom, 82,429 men between 50 and 69 years of age received a prostate-specific antigen (PSA) test. Localized prostate cancer was diagnosed in 2664 men. Of these men, 1643 were enrolled in a trial to evaluate the effectiveness of treatments, with 545 randomly assigned to receive active monitoring, 553 to undergo prostatectomy, and 545 to undergo radiotherapy. METHODS At a median follow-up of 15 years (range, 11 to 21), we compared the results in this population with respect to death from prostate cancer (the primary outcome) and death from any cause, metastases, disease progression, and initiation of long-term androgen-deprivation therapy (secondary outcomes). RESULTS Follow-up was complete for 1610 patients (98%). A risk-stratification analysis showed that more than one third of the men had intermediate or high-risk disease at diagnosis. Death from prostate cancer occurred in 45 men (2.7%): 17 (3.1%) in the active-monitoring group, 12 (2.2%) in the prostatectomy group, and 16 (2.9%) in the radiotherapy group (P=0.53 for the overall comparison). Death from any cause occurred in 356 men (21.7%), with similar numbers in all three groups. Metastases developed in 51 men (9.4%) in the active-monitoring group, in 26 (4.7%) in the prostatectomy group, and in 27 (5.0%) in the radiotherapy group. Long-term androgen-deprivation therapy was initiated in 69 men (12.7%), 40 (7.2%), and 42 (7.7%), respectively; clinical progression occurred in 141 men (25.9%), 58 (10.5%), and 60 (11.0%), respectively. In the active-monitoring group, 133 men (24.4%) were alive without any prostate cancer treatment at the end of follow-up. No differential effects on cancer-specific mortality were noted in relation to the baseline PSA level, tumor stage or grade, or risk-stratification score. No treatment complications were reported after the 10-year analysis. CONCLUSIONS After 15 years of follow-up, prostate cancer–specific mortality was low regardless of the treatment assigned. Thus, the choice of therapy involves weighing trade-offs between benefits and harms associated with treatments for localized prostate cancer. (Funded by the National Institute for Health and Care Research; ProtecT Current Controlled Trials number, ISRCTN20141297. opens in new tab; ClinicalTrials.gov number, NCT02044172.) [ABSTRACT FROM AUTHOR]

Purpose. To use cognitive interviewing techniques to assess comprehension of existing Patient-Reported Outcomes Measurement Information System (PROMIS) items among Latinos living with HIV and then refine items based on participant feedback. Methods. Latino monolingual Spanish speakers living with HIV (n=56) participated in cognitive interviews. Items from four PROMIS domains, including depression, anxiety, fatigue, and alcohol use, were assessed for comprehension. Audiotaped interviews and handwritten notes were subjected to content analysis to identify problems specific to each instrument for each domain. Results. The assessments from the cognitive interviews identified areas for improvement in each domain. We present data on the type of items that were difficult to comprehend and provide examples for how items were refined based on participants’ and PROMIS Statistical Coordinating Center (PSCC) feedback. Six out of 48 depression items, 7 out of the 61 anxiety items, 18 out of 42 fatigue items, and 7 out of 44 alcohol use items were found to have poor comprehension. These items were refined based on participant feedback; the items were then submitted to the PSCC for additional guidance on linguistics and grammar to improve comprehension. Conclusions. Cognitive interviews may be used to enhance comprehension of PROMIS items among Latinos. [ABSTRACT FROM AUTHOR]

Introduction: Rates of sexually transmitted infection (STI) are rising in the USA, yet STI risk remains under-addressed by providers, even in HIV care, and with high-risk patients. We interviewed primary care patients living with and without HIV regarding circumstances surrounding sexual risk behavior to identify opportunities for providers to address and reduce STI risk.Methods: We conducted semi-structured 1:1 interviews with patients living with and without HIV reporting ≥ 1 sex partner and varying STI exposure risk in the past 12 months from four geographically diverse US HIV and primary care clinics. We audio-recorded, transcribed, and coded interviews by circumstance type, using double-coding to ensure inter-coder reliability. We used Fisher's exact and T tests to determine associations with demographic/risk factors.Results: Patients (n = 91) identified a mean of 3 of 11 circumstances. These included substance use (54%), desire for physical/emotional intimacy (48%), lack of HIV/STI status disclosure (44%), psychological drivers (i.e., coping, depression; 38%), personal dislike of condoms (22%), partner condom dislike/refusal (19%), receiving payment for sex (13%), and condom unavailability (9%). Higher proportions of those who were high STI-exposure risk patients, defined as those with ≥ 2 sex partners in the past 3 months reporting never or sometimes using condoms, reported disliking condoms (p = .006); higher proportions of the high-risk and moderate-risk (≥ 2 partners and condom use "most of the time") groups reported substance use as a circumstance (p = .04).Conclusion: Circumstances surrounding perceived STI exposure risk were diverse, often overlapping, and dependent on internal, environmental, and partner-related factors and inadequate communication. Meaningful care-based interventions regarding HIV/STI transmission behavior must address the diversity and interplay of these factors. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate psychometric characteristics and cross-sectional and longitudinal validity of the 7-item PROMIS® Fatigue Short Form and additional fatigue items among people living with HIV (PLWH) in a nationally distributed network of clinics collecting patient reported data at the time of routine clinical care. Methods: Cross-sectional and longitudinal fatigue data were collected from September 2012 through April 2013 across clinics participating in the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS). We analyzed data regarding psychometric characteristics including simulated computerized adaptive testing and differential item functioning, and regarding associations with clinical characteristics. Results: We analyzed data from 1597 PLWH. Fatigue was common in this cohort. Scores from the PROMIS® Fatigue Short Form and from the item bank had acceptable psychometric characteristics and strong evidence for validity, but neither performed better than shorter instruments already integrated in CNICS. Conclusions: The PROMIS® Fatigue Item Bank is a valid approach to measuring fatigue in clinical care settings among PLWH, but in our analyses did not perform better than instruments associated with less respondent burden. [ABSTRACT FROM AUTHOR]

The adsorption capacity of uncalcined and calcined layered double hydroxide (LDH) for fluoride removal was studied in this work. The LDH was synthesized by a co-precipitation method and calcined at various temperatures. The equilibrium data for fluoride adsorption on the LDHs were obtained in a batch adsorber, and the Freundlich isotherm model showed a better fit to the data. The LDH was chemically stable over the pH range of 5-12, but readily dissolved when the pH was below 5. The fluoride adsorption capacity of LDH decreased by raising the pH due to electrostatic interactions, and presented a maximum at 25 °C. The adsorption capacity of LDH was influenced by the calcination temperature and was enhanced by increasing the calcination temperature. The calcination destroyed the crystalline structure of the LDH, which was recovered when the calcined LDH was rehydrated in aqueous solution. The calcined LDH had a very high adsorption capacity towards fluoride. [ABSTRACT FROM AUTHOR]