Chromogenic Escherichia coli reporter strain for screening DNA damaging agents.

The presence of pollutants in soil and water has given rise to diverse analytical and biological approaches to detect and measure contaminants in the environment. Using bacterial cells as reporter strains represents an advantage for detecting pollutants present in soil or water samples. Here, an Escherichia coli reporter strain expressing a chromoprotein capable of interacting with soil or water samples and responding to DNA damaging compounds is validated. The reporter strain generates a qualitative signal and is based on the expression of the coral chromoprotein AmilCP under the control of the recA promoter. This strain can be used simply by applying soil or water samples directly and rendering activation upon DNA damage. This reporter strain responds to agents that damage DNA (with an apparent detection limit of 1 µg of mitomycin C) without observable response to membrane integrity damage, protein folding or oxidative stress generating agents, in the latter case, DNA damage was observed. The developed reporter strain reported here is effective for the detection of DNA damaging agents present in soils samples. In a proof-of-concept analysis using soil containing chromium, showing activation at 15.56 mg/L of Cr(VI) present in soil and leached samples and is consistent with Cr(III) toxicity at high concentrations (130 µg). Our findings suggest that chromogenic reporter strains can be applied for simple screening, thus reducing the number of samples requiring analytical techniques.

Sulfur Deprivation Modulates Salicylic Acid Responses via Nonexpressor of Pathogenesis-Related Gene 1 in Arabidopsis thaliana.

Mineral nutrients are essential for plant growth and reproduction, yet only a few studies connect the nutritional status to plant innate immunity. The backbone of plant defense response is mainly controlled by two major hormones: salicylic acid (SA) and jasmonic acid (JA). This study investigated changes in the macronutrient concentration (deficiency/excess of nitrogen, phosphorus, potassium, magnesium, and sulfur) on the expression of PR1, a well-characterized marker in the SA-pathway, and PDF1.2 and LOX2 for the JA-pathway, analyzing plants carrying the promoter of each gene fused to GUS as a reporter. After histochemical GUS assays, we determined that PR1 gene was strongly activated in response to sulfur (S) deficiency. Using RT-PCR, we observed that the induction of PR1 depended on the function of Non-expressor of Pathogenesis-Related gene 1 (NPR1) and SA accumulation, as PR1 was not expressed in npr1-1 mutant and NahG plants under S-deprived conditions. Plants treated with different S-concentrations showed that total S-deprivation was required to induce SA-mediated defense responses. Additionally, bioassays revealed that S-deprived plants, induced resistance to the hemibiotrophic pathogen Pseudomonas syringae pv. DC3000 and increase susceptibility to the necrotrophic Botrytis cinerea. In conclusion, we observed a relationship between S and SA/JA-dependent defense mechanisms in Arabidopsis.

Racial/ethnic and educational differences in perceptions and use of a new urban trail.

ABSTRACTObjectives: Obesity and its associated health risks are on the rise throughout the US due, in part, to an overall decline in physical activity. Although public green spaces, and in particular trails, show promise as population-level interventions to promote physical activity among adults, these amenities may have disparate impacts across racial/ethnic and socioeconomic groups within a community.Design: This cross-sectional study employed an intercept survey of users of a newly opened $95 million rail-to-trail development in Chicago, IL, immediately after its opening and one year later to examine differences by race/ethnicity and educational attainment in trail use behaviors, motivations for trail use, safety concerns, and change in physical activity attributed to the trail.Results: Although the overall impact of the trail was positive, Latino users were more likely to report frequent use (4+ times/week), health motivations for using the trail, and increased physical activity attributed to the trail. However, Latino users were also more likely to indicate safety concerns and less likely to use areas of the trail in predominately white communities, even after controlling for community of residence. The least educated trail users frequented fewer trail areas and were less likely to indicate health motivations for trail use.Conclusions: Although urban trails represent an opportunity for cost-effective community-wide health promotion, they may not benefit all groups equally. Urban trails may have particularly promising benefits for Latino users, but safety concerns and the possibility of community racial segregation being replicated on trails should be addressed to maximize and sustain these benefits. Less educated residents in particular may not benefit from such projects as intended.

aeBlue Chromoprotein Color is Temperature Dependent.

BACKGROUND: Marine sessile organisms display a color palette that is the result of the expression of fluorescent and non-fluorescent proteins. Fluorescent proteins have uncovered transcriptional regulation, subcellular localization of proteins, and the fate of cells during development. Chromoproteins have received less attention until recent years as bioreporters. Here, we studied the properties of aeBlue, a a 25.91 kDa protein from the anemone Actinia equina. OBJECTIVE: To assess the properties of aeBlue chromoprotein under different physicochemical conditions. METHODS: In this article, during the purification of aeBlue we uncovered that it suffered a color shift when frozen. We studied the color shift by different temperature incubation and physicochemical conditions and light spectroscopy. To assess the possible structural changes in the protein, circular dichroism analysis, size exclusion chromatography and native PAGE was performed. RESULTS: We uncover that aeBlue chromoprotein, when expressed from a synthetic construct in Escherichia coli, showed a temperature dependent color shift. Protein purified at 4 °C by metal affinity chromatography exhibited a pinkish color and shifts back at higher temperatures to its intense blue color. Circular dichroism analysis revealed that the structure in the pink form of the protein has reduced secondary structure at 4 °C, but at 35 °C and higher, the structure shifts to a native conformation and Far UV- vis CD spectra revealed the shift in an aromatic residue of the chromophore. Also, the chromophore retains its properties in a wide range of conditions (pH, denaturants, reducing and oxidants agents). Quaternary structure is also maintained as a tetrameric conformation as shown by native gel and size exclusion chromatography. CONCLUSION: Our results suggest that the chromophore position in aeBlue is shifted from its native position rendering the pink color and the process to return it to its native blue conformation is temperature dependent.

Validación instrumento percepción de cuidados humanizados de enfermería (PCHE) / Validation tool perceived behavior humanized nursing care (PCHE)

INTRODUCCIÓN: La validación de escalas de cuidado en enfermería es un problema relevante para la ética del cuidado y la gestión de calidad. OBJETIVO: validar el instrumento, "Percepción de comportamientos de cuidados humanizados de enfermería" (PCHE), en usuarios de Unidades Clínicas. METODOLOGÍA: diseño descriptivo de corte transversal, en muestra de 367 usuarios, con nivel de confianza de 95%. RESULTADOS: instrumento con alfa de Cronbach 0,89. El factor 6, presentó un valor insatisfactorio, y se conformó con dos ítems, lo cual es insuficiente para ser considerado. DISCUSIÓN: Los ítems presentan una conformación distinta a los encontrados en Colombia. Para mayor solidez y consistencia a los resultados, se debe examinar el instrumento en distintas poblaciones y revisar la sexta dimensión. CONCLUSIONES: se demostró que el instrumento, es válido y fiable.

INTRODUCTION: The scale validation of nursing care is relevant to the ethics of care and quality management problem. OBJECTIVE: To validate the instrument "Perception of behaviors of humanized nursing care" (PCHE) in users of clinical units. METHODOLOGY: A descriptive cross-sectional design, in sample 367 users, with confidence level of 95%. RESULTS: Cronbach instrument 0.89. Factor 6, presented an unsatisfactory value, and settled for two items, which is insufficient to be considered DISCUSSION: The items have a different to those found in Colombia conformation. For more strength and consistency to the results, one must examine the instrument in different populations and revise the sixth dimension. CONCLUSIONS: These results show the instrument is valid and reliable.

Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems.

Here we report experimental simulations of hydrothermal chimney growth using injection chemical garden methods. The versatility of this type of experiment allows for testing of various proposed ocean / hydrothermal fluid chemistries that could have driven reactions toward the origin of life in environments on the early Earth, early Mars, or even other worlds such as the icy moons of the outer planets. We show experiments that include growth of chemical garden structures under anoxic conditions simulating the early Earth, inclusion of trace components of phosphates / organics in the injection solution to incorporate them into the structure, a switch of the injection solution to introduce a secondary precipitating anion, and the measurement of membrane potentials generated by chemical gardens. Using this method, self-assembling chemical garden structures were formed that mimic the natural chimneys precipitated at submarine hydrothermal springs, and these precipitates can be used successfully as flow-through reactors by feeding through multiple successive "hydrothermal" injections.

Frequency and clinicopathological characteristics of presenilin 1 Gly206Ala mutation in Puerto Rican Hispanics with dementia.

The frequency and clinical and pathological characteristics associated with the Gly206Ala presenilin 1 (PSEN1) mutation in Puerto Rican and non-Puerto Rican Hispanics were evaluated at the University of Pennsylvania's Alzheimer's Disease Center. DNAs from all cohort subjects were genotyped for the Gly206Ala PSEN1 mutation. Carriers and non-carriers with neurodegenerative disease dementias were compared for demographic, clinical, psychometric, and biomarker variables. Nineteen (12.6%) of 151 unrelated subjects with dementia were discovered to carry the PSEN1 Gly206Ala mutation. Microsatellite marker genotyping determined a common ancestral haplotype for all carriers. Carriers were all of Puerto Rican heritage with significantly younger age of onset, but otherwise were clinically and neuropsychologically comparable to those of non-carriers with AD. Three subjects had extensive topographic and biochemical biomarker assessments that were also typical of non-carriers with AD. Neuropathological examination in one subject revealed severe, widespread plaque and tangle pathology without other meaningful disease lesions. The PSEN1 Gly206Ala mutation is notably frequent in unrelated Puerto Rican immigrants with dementia in Philadelphia. Considered together with the increased prevalence and mortality of AD reported in Puerto Rico, these high rates may reflect hereditary risk concentrated in the island which warrants further study.

Ethnoracial differences in the clinical characteristics of Alzheimer's disease at initial presentation at an urban Alzheimer's disease center.

OBJECTIVE: To compare presentation of Alzheimer disease (AD) at the time of initial evaluation at a university specialty clinic across three ethnoracial groups in order to understand similarities and differences in the demographic, clinical, cognitive, psychiatric, and biologic features. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 1,341 self-identified African American, Latino (primarily of Caribbean origin), and white non-Hispanic ("WNH") subjects were recruited from primary care sites or by referral by primary care physicians. MEASUREMENTS: Demographic variables and age of onset of AD, as well as cognitive, functional, and mood impairments at the time of initial presentation and frequencies of apolipoprotein E genotypes, were compared across groups. RESULTS: Differences among ethnoracial groups were found for nearly all variables of interest. In particular, the largely immigrant Puerto Rican Latino group had an earlier age of onset of AD, more cognitive impairment, and greater severity of cognitive impairment at the time of initial evaluation in the setting of low average education and socioeconomic status. There was more depression in the Latinos compared with African Americans and WNHs. Greater severity of symptoms was not accounted for by a difference in lag time between onset of symptoms and initial evaluation. The apolipoprotein E-4 genotype was not associated with AD in the Latino cohort. CONCLUSIONS: Minority groups in Philadelphia, especially Latinos, exhibit a more severe profile of AD at the time of presentation than WNHs. Important potential confounds need to be considered and future research comparing immigrant and nonimmigrant Latino groups will be necessary to elucidate the highly significant differences reported.

What Latino Puerto Ricans and non-Latinos say when they talk about Alzheimer's disease.

BACKGROUND: To discover whether Latino Puerto Rican and non-Latino communities differ in the words they use to talk about Alzheimer's disease (AD). METHODS: Four groups of 30 persons per group defined by self-identified ethnicity and caregiver status: Latino Puerto Ricans and non-Latino Whites, who were either caregivers or non-caregivers completed free-listing exercises to identify the words they use when they describe AD causes, symptoms, caregiving, and research risks and benefits. RESULTS: Both Latino Puerto Ricans and non-Latino Whites recognize AD as a disease of memory loss and other cognitive problems. Although both groups used the term "sadness" to describe AD, non-Latino Whites did not feature emotional, behavioral, or psychological problems as among the causes of AD. Although all the groups' descriptions of a person who lives with and cares for a person with AD shared the word "loving," Latino Puerto Ricans focused on a good spouse who exercises intelligence, patience, and attention on behalf of the person with AD and did not use the term "caregiver." In contrast, non-Latino Whites typically used the term "caregiver." Both groups' lists shared words that describe research as presenting harms to an AD patient and requiring a commitment of time. Latino Puerto Ricans' lists suggested an understanding of research benefits akin to clinical care. CONCLUSIONS: Notable differences exist in how Latino Puerto Ricans and non-Latino Whites talk about AD and AD research. Clinicians, clinical investigators, and patient educators need to consider these differences when they conduct clinical care and research and design outreach and educational materials.

Earlier onset of Alzheimer disease symptoms in latino individuals compared with anglo individuals.

BACKGROUND: Latino individuals are the largest minority group and the fastest growing population group in the United States, yet there are few studies comparing the clinical features of Alzheimer disease (AD) in this population with those found in Anglo (white non-Latino) patients. OBJECTIVE: To compare the age at AD symptom onset in Latino and Anglo individuals. DESIGN: Cross-sectional assessment using standardized methods to collect and compare age at AD symptom onset, demographic variables, and medical variables. SETTING: Five National Institute on Aging-sponsored Alzheimer's Disease Centers with experience evaluating Spanish-speaking individuals. PATIENTS: We evaluated 119 Latino and 55 Anglo patients who had a diagnosis of AD. MAIN OUTCOME MEASURE: Age at symptom onset. RESULTS: After adjusting for center, sex, and years of education, Latino patients had a mean age at symptom onset 6.8 years earlier (95% confidence interval, 3.5-10.3 years earlier) than Anglo patients. CONCLUSIONS: An earlier age at symptom onset suggests that US mainland Latino individuals may experience an increased burden of AD compared with Anglo individuals. The basis for the younger age at symptom onset remains obscure.