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Find video protocols related to scientific articles indexed in Pubmed.
Effects of Shigella-, Campylobacter- and ETEC-associated Diarrhea on Childhood Growth.
Pediatr. Infect. Dis. J.
PUBLISHED: 11-01-2014
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Studies examining the etiology-specific effects of diarrheal disease on growth are limited and variable in their analytic methods, making comparisons difficult and priority setting based on these findings challenging. A study by Black et al (Black RE, Brown KH, Becker S. Effects of diarrhea associated with specific enteropathogens on the growth of children in rural Bangladesh. Pediatrics. 1984;33:1004-1009.) examined the association between Shigella and enterotoxigenic Escherichia coli-related disease and weight gain and linear growth in Bangladeshi children aged 0-5 years. We estimated similar associations in a 2002 cohort of 0- to 6-year-old children in the Peruvian Amazon.
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Examining the relationship between head trauma and neurodegenerative disease: A review of epidemiology, pathology and neuroimaging techniques.
J Alzheimers Dis Parkinsonism
PUBLISHED: 10-18-2014
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Traumatic brain injuries (TBI) are induced by sudden acceleration-deceleration and/or rotational forces acting on the brain. Diffuse axonal injury (DAI) has been identified as one of the chief underlying causes of morbidity and mortality in head trauma incidents. DAIs refer to microscopic white matter (WM) injuries as a result of shearing forces that induce pathological and anatomical changes within the brain, which potentially contribute to significant impairments later in life. These microscopic injuries are often unidentifiable by the conventional computed tomography (CT) and magnetic resonance (MR) scans employed by emergency departments to initially assess head trauma patients and, as a result, TBIs are incredibly difficult to diagnose. The impairments associated with TBI may be caused by secondary mechanisms that are initiated at the moment of injury, but often have delayed clinical presentations that are difficult to assess due to the initial misdiagnosis. As a result, the true consequences of these head injuries may go unnoticed at the time of injury and for many years thereafter. The purpose of this review is to investigate these consequences of TBI and their potential link to neurodegenerative disease (ND). This review will summarize the current epidemiological findings, the pathological similarities, and new neuroimaging techniques that may help delineate the relationship between TBI and ND. Lastly, this review will discuss future directions and propose new methods to overcome the limitations that are currently impeding research progress. It is imperative that improved techniques are developed to adequately and retrospectively assess TBI history in patients that may have been previously undiagnosed in order to increase the validity and reliability across future epidemiological studies. The authors introduce a new surveillance tool (Retrospective Screening of Traumatic Brain Injury Questionnaire, RESTBI) to address this concern.
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Environmental health literacy in support of social action: an environmental justice perspective.
J Environ Health
PUBLISHED: 09-05-2014
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Different demographic groups in the U.S. experience unequal exposures to environmental hazards, i.e., 56% of the population in neighborhoods containing commercial waste facilities are people of color, with the associated poverty rates in those communities being 50% higher than in neighborhoods without commercial waste facilities. Developing programs to educate communities about environmental hazards affecting their health and quality of life is an essential component for a community to understand their true risk. The study described in this article examined the risk of environmental hazards as perceived by public housing residents and assessed the residents' preference for educational programs on environmental hazards. Residents perceived their risk factors in a broad context and they included environmental health risks caused by pollutants along with physical safety concerns from crime and law enforcement interactions. The most trusted sources of information on environmental health include community organizations, trusted individuals in the community, and television programs. Recommendations for developing community-specific environmental health education programs include using sources of environmental health information that community members trust.
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Outcomes of serial dilation for high-grade radiation-related esophageal strictures in head and neck cancer patients.
Laryngoscope
PUBLISHED: 08-31-2014
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Dysphagia and esophageal stricture are frequent consequences of treatment for head and neck cancer. This study examines the effectiveness of the anterograde-retrograde rendezvous procedure and serial dilations in reestablishing esophageal patency to allow return to oral diet and gastrostomy tube removal in a cohort of patients with complete or near-complete esophageal stricture following nonsurgical cancer treatment.
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Design considerations for point-of-care clinical trials comparing methadone and buprenorphine treatment for opioid dependence in pregnancy and for neonatal abstinence syndrome.
Contemp Clin Trials
PUBLISHED: 08-23-2014
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In recent years, the U.S. has experienced a significant increase in the prevalence of pregnant opioid-dependent women and of neonatal abstinence syndrome (NAS), which is caused by withdrawal from in-utero drug exposure. While methadone-maintenance currently is the standard of care for opioid dependence during pregnancy, research suggests that buprenorphine-maintenance may be associated with shorter infant hospital lengths of stay (LOS) relative to methadone-maintenance. There is no "gold standard" treatment for NAS but there is evidence that buprenorphine, relative to morphine or methadone, treatment may reduce LOS and length of treatment.
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Neutrophil CD64 as a Diagnostic Marker of Sepsis: Impact on Neonatal Care.
Am J Perinatol
PUBLISHED: 07-31-2014
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Objective?The aim of this study is to determine the validity and reliability of neutrophil CD64 in identifying infected infants and to evaluate the impact of this marker on clinical care. Study Design?Neutrophil CD64 index was incorporated in 371 infection evaluations in 234 infants (ages 1-293 days) from 2005 to 2009 and the impact of this change on clinical care was evaluated. Results?The sensitivity of the neutrophil CD64 assay was 87% in identifying 31 episodes of culture positive sepsis and 83% in identifying 12 infants with ventilator-associated pneumonia. There was no difference in the mean number of antibiotic days in infants with a normal CD64 versus those with a normal complete blood count (CBC) (p?=?0.89), but twofold more infants were identified as "not infected" by CD64 than by CBC. Conclusion?CD64 had a high sensitivity for identifying infected infants while also decreasing the number of infants that were exposed to unnecessary antibiotic use.
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A multicenter cohort study of treatments and hospital outcomes in neonatal abstinence syndrome.
Pediatrics
PUBLISHED: 07-30-2014
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To compare pharmacologic treatment strategies for neonatal abstinence syndrome (NAS) with respect to total duration of opioid treatment and length of inpatient hospital stay.
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Concussion Management in Collegiate Student-Athletes: Return-To-Academics Recommendations.
Clin J Sport Med
PUBLISHED: 07-11-2014
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: Concussions in collegiate athletics can affect student-athletes both on the field and in the classroom. As policies are made to outline return-to-play decisions and timelines, this article will make the case that return-to-academics should also be included and follow a step-wise protocol. Complete cognitive rest is a cornerstone of concussion recovery and slow reintroduction to academics should precede return-to-play. The college structure allows for student-athletes to begin small doses of cognitive activity after the recommended complete cognitive rest. It is recommended that return-to-academics involves a team approach to help the student-athlete navigate the responsibilities of course work while healing from a brain injury.
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Microdroplet temperature calibration via thermal dissociation of quenched DNA oligomers.
Biomed Opt Express
PUBLISHED: 03-01-2014
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The development of microscale analytical techniques has created an increasing demand for reliable and accurate heating at the microscale. Here, we present a novel method for calibrating the temperature of microdroplets using quenched, fluorescently labeled DNA oligomers. Upon melting, the 3' fluorophore of the reporter oligomer separates from the 5' quencher of its reverse complement, creating a fluorescent signal recorded as a melting curve. The melting temperature for a given oligomer is determined with a conventional quantitative polymerase chain reaction (qPCR) instrument and used to calibrate the temperature within a microdroplet, with identical buffer concentrations, heated with an infrared laser. Since significant premelt fluorescence prevents the use of a conventional (single-term) sigmoid or logistic function to describe the melting curve, we present a three-term sigmoid model that provides a very good match to the asymmetric fluorescence melting curve with premelting. Using mixtures of three oligomers of different lengths, we fit multiple three-term sigmoids to obtain precise comparison of the microscale and macroscale fluorescence melting curves using "extrapolated two-state" melting temperatures.
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Role of self-reported individual differences in preference for and tolerance of exercise intensity in fitness testing performance.
J Strength Cond Res
PUBLISHED: 02-18-2014
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Performance in fitness tests could depend on factors beyond the bioenergetic and skeletomuscular systems, such as individual differences in preference for and tolerance of different levels of exercise-induced somatosensory stimulation. Although such individual-difference variables could play a role in exercise testing and prescription, they have been understudied. The purpose of these studies was to examine the relationships of self-reported preference for and tolerance of exercise intensity with performance in fitness tests. Participants in study I were 516 men and women volunteers from a campus community, and participants in study II were 42 men recruit firefighters undergoing a 6-week training program. Both the Preference and Tolerance scores exhibited significant relationships with performance in several fitness tests and with body composition and physical activity participation. Preference and Tolerance did not change after the training program in study II, despite improvements in objective and perceived fitness, supporting their conceptualization as dispositional traits. Preference and Tolerance scores could be useful not only in ameliorating the current understanding of the determinants of physical performance, but also in personalizing exercise prescriptions and, thus, delivering exercise experiences that are more pleasant, tolerable, and sustainable.
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Evaluating the treatment of a synthetic wastewater containing a pharmaceutical and personal care product chemical cocktail: compound removal efficiency and effects on juvenile rainbow trout.
Water Res.
PUBLISHED: 02-09-2014
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Pharmaceutical and personal care products (PPCPs) can evade degradation in sewage treatment plants (STPs) and can be chronically discharged into the environment, causing concern for aquatic organisms, wildlife, and humans that may be exposed to these bioactive chemicals. The ability of a common STP process, conventional activated sludge (CAS), to remove PPCPs (caffeine, di(2-ethylhexyl)phthalate, estrone, 17?-ethinylestradiol, ibuprofen, naproxen, 4-nonylphenol, tonalide, triclocarban and triclosan) from a synthetic wastewater was evaluated in the present study. The removal of individual PPCPs by the laboratory-scale CAS treatment plant ranged from 40 to 99.6%. While the efficiency of removal for some compounds was high, remaining quantities have the potential to affect aquatic organisms even at low concentrations. Juvenile rainbow trout (Oncorhynchus mykiss) were exposed to influent recreated model wastewater with methanol (IM, solvent control) or with PPCP cocktail (IC), or CAS-treated effluent wastewater with methanol (EM, treated control) or with PPCP cocktail (EC). Alterations in hepatic gene expression (evaluated using a quantitative nuclease protection plex assay) and plasma vitellogenin (VTG) protein concentrations occurred in exposed fish. Although there was partial PPCP removal by CAS treatment, the 20% lower VTG transcript levels and 83% lower plasma VTG protein concentration found in EC-exposed fish compared to IC-exposed fish were not statistically significant. Thus, estrogenic activity found in the influent was retained in the effluent even though typical percent removal levels were achieved raising the issue that greater reduction in contaminant load is required to address hormone active agents.
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Endobronchial ultrasonography versus mediastinoscopy: a single-institution cost analysis and waste comparison.
Ann. Thorac. Surg.
PUBLISHED: 01-29-2014
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Mediastinoscopy (MED) and endobronchial ultrasonography with transbronchial needle aspiration (EBUS-TBNA) have similar accuracy for mediastinal lymph node sampling (MLNS). The threatened financial and environmental sustainability of our health care system mandate that surgeons consider cost and environmental impact in clinical decision making of similarly effective procedures. We performed a cost and waste comparison of MED versus EBUS-TBNA for MLNS to raise awareness of the financial and environmental implications of our practices.
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Phenotyping for patient safety: algorithm development for electronic health record based automated adverse event and medical error detection in neonatal intensive care.
J Am Med Inform Assoc
PUBLISHED: 01-08-2014
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Although electronic health records (EHRs) have the potential to provide a foundation for quality and safety algorithms, few studies have measured their impact on automated adverse event (AE) and medical error (ME) detection within the neonatal intensive care unit (NICU) environment.
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Exploring the activated adipogenic niche: interactions of macrophages and adipocyte progenitors.
Cell Cycle
PUBLISHED: 01-06-2014
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Adult adipose tissue contains a large supply of progenitors that can renew fat cells for homeostatic tissue maintenance and adaptive growth or regeneration in response to external challenges. However, the in vivo mechanisms that control adipocyte progenitor behavior are poorly characterized. We recently demonstrated that recruitment of adipocyte progenitors by macrophages is a central feature of adipose tissue remodeling under various adipogenic conditions. Catabolic remodeling of white adipose tissue by ?3-adrenergic receptor stimulation requires anti-inflammatory M2-polarized macrophages to clear dying adipocytes and to recruit new brown adipocytes from progenitors. In this Extra Views article, we discuss in greater detail the cellular elements of adipogenic niches and report a strategy to isolate and characterize the subpopulations of macrophages and adipocyte progenitors that actively participate in adrenergic tissue remodeling. Further characterization of these subpopulations may facilitate identification of new cellular targets to improve metabolic and immune function of adipose tissue.
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Association of Maternal and Community Factors With Enrollment in Home Visiting Among At-Risk, First-Time Mothers.
Am J Public Health
PUBLISHED: 12-19-2013
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Objectives. We identified individual and contextual factors associated with referral and enrollment in home visiting among at-risk, first-time mothers. Methods. We retrospectively studied referral and enrollment in a regional home visiting program from 2007 to 2009 in Hamilton County, Ohio. Using linked vital statistics and census tract data, we obtained individual and community measures on first-time mothers meeting eligibility criteria for home visiting (low income, unmarried, or age?
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Validation of a Novel Murine Wound Model of Acinetobacter baumannii Infection.
Antimicrob. Agents Chemother.
PUBLISHED: 12-16-2013
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Patients recovering from traumatic injuries or surgery often require weeks to months-long hospitalization, increasing the risk for wound and surgical site infections caused by ESKAPE pathogens such as A. baumannii. As new therapies are being developed to counter A. baumannii infections; animal models are also needed to evaluate these potential treatments. Here, we present here an excisional, murine wound model in which a diminutive inoculum of a clinically-relevant, multidrug-resistant A. baumannii isolate can proliferate, form biofilm, and be effectively treated with antibiotics. The model requires a temporary, cyclophosphamide-induced neutropenia to establish an infection that can persist. A six millimeter diameter, full-thickness wound is created in the skin overlying the thoracic spine, and after the wound bed is inoculated, it is covered with a dressing for 7 days. Un-inoculated control wounds heal within 13 days; whereas infected, placebo-treated wounds remain unclosed beyond 21 days. Treated and untreated wounds are assessed with multiple quantitative and qualitative techniques to include: gross pathology, weight loss and recovery, wound closure, bacterial burden, 16S community profiling, histopathology, PNA-FISH, and SEM assessment of biofilm. The range of differences between antibiotic and placebo-treated animals that were identified with these measures provides a clear window within which novel antimicrobial therapies can be assessed. The model can evaluate antimicrobials for the ability to reduce specific pathogen load in wounded tissue and clear biofilm. Ultimately, the mouse-model approach allows for highly powered studies and serves as an initial multi-faceted in vivo assessment prior to testing in larger animals.
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Dosage effect of prenatal home visiting on pregnancy outcomes in at-risk, first-time mothers.
Pediatrics
PUBLISHED: 11-05-2013
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Home visiting programs seek to improve care management for women at high risk for preterm birth (<37 weeks). Our objective was to evaluate the effect of home visiting dosage on preterm birth and small for gestational age (SGA) infants.
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Detection of leptospira-specific antibodies using a recombinant antigen-based enzyme-linked immunosorbent assay.
Am. J. Trop. Med. Hyg.
PUBLISHED: 10-28-2013
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Abstract. We produced three highly purified recombinant antigens rLipL32, rLipL41, and rLigA-Rep (leptospiral immunoglobulin-like A repeat region) for the detection of Leptospira-specific antibodies in an enzyme-linked immunosorbent assay (ELISA). The performance of these recombinant antigens was evaluated using 121 human sera. Among them, 63 sera were microscopic agglutination test (MAT)-confirmed positive sera from febrile patients in Peru, 22 sera were indigenous MAT-negative febrile patient sera, and 36 sera were from patients with other febrile diseases from Southeast Asia, where leptospirosis is also endemic. Combining the results of immunoglobulin M (IgM) and IgG detection from these three antigens, the overall sensitivity is close to 90% based on the MAT. These results suggest that an ELISA using multiple recombinant antigens may be used as an alternative method for the detection of Leptospira-specific antibodies.
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Moderno love: sexual role-based identities and HIV/STI prevention among men who have sex with men in Lima, Peru.
AIDS Behav
PUBLISHED: 09-18-2013
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Role-based sexual identities structure male same-sex partnerships and influence HIV/STI epidemiology among MSM in Latin America. We explored shifting relationships between sexual roles, identities and practices among MSM in Lima, Peru, and implications for HIV/STI prevention. Patterns of HIV/STI epidemiology reflected differential risks for transmission within role-based partnerships with relatively low prevalences of HIV, syphilis, and HSV-2 but higher prevalences of urethral gonorrhea/chlamydia among activo MSM compared with moderno and pasivo participants. Qualitative analysis of how MSM in Peru integrate sexual identities, roles, and practices identified four key themes: pasivo role as a gay approximation of cultural femininity; activo role as a heterosexual consolidation of masculinity; moderno role as a masculine reconceptualization of gay identity; and role-based identities as social determinants of partnership, network, and community formation. The concept of role-based sexual identities provides a framework for HIV prevention for Latin American MSM that integrates sexual identities, practices, partnerships, and networks.
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Biological removal of phyto-sterols in pulp mill effluents.
J. Environ. Manage.
PUBLISHED: 09-03-2013
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Phyto-sterols and extractives found in pulp mill effluents are suspected to cause endocrine abnormalities in receiving water fish. The control of sterols in pulp mill effluents through biological secondary wastewater treatment was studied using two lab-scale bioreactor systems. After achieving a stable performance, both bioreactor systems successfully removed (>90%) sterols and the estimated biodegradation was up to 80%. Reactor 1 system operating at 6.7 ± 0.2 pH effectively treated pulp mill effluent sterols spiked up to 4500 ?g/L in 11 h HRT and 11 day SRT. However, Reactor 2 system operating at 7.6 ± 0.2 pH performed relatively poorly. Retention time reductions beyond critical values deteriorated the performance of treatment systems and quickly reduced the sterols biodegradation. The biodegradation loss was indicated by mixed liquor sterols content that started increasing. This biodegradation loss was compensated by the increased role of bio-adsorption and the overall sterols removal remained relatively high. Hence, a relatively small (20-30%) loss in the overall sterols removal efficiency did not fully reflect the associated major (60-70%) loss in the sterols biodegradation because the amount of sterols accumulated in the sludge due to adsorption increased so the estimate of sterols removal through adsorption increased from 30-40% to 70-80% keeping the overall sterols removal still high.
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Relationship between alcohol consumption prior to sex, unprotected sex and prevalence of STI/HIV among socially marginalized men in three coastal cities of Peru.
AIDS Behav
PUBLISHED: 08-31-2013
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This article presents data about the relationship between alcohol consumption prior to sex and unprotected sex and the prevalence of at least one sexually transmitted infection (STI) including HIV among socially marginalized men in three coastal Peruvians cities. During an epidemiological survey with 2,146 men, we assessed their STI prevalence, frequency of alcohol consumption prior to sex, unprotected sex and other sexual risk behaviors. The overall prevalence of at least one STI/HIV was 8.5 % (95 % CI 7.3-9.7), the prevalence of unprotected sex was 79.1 % (95 % CI 77.8-80.3) and alcohol consumption prior to sex with any of the last five sex partners in the previous 6 months was 68.9 % (95 % CI 66.9-70.9). Bivariate and multivariate analysis showed that alcohol consumption of participants or their partners prior to sex were associated with the prevalence of at least one STI, adjusted Prevalence Ratio (aPR) = 1.3 (95 % CI 1.01-1.68). Unprotected sex was significantly associated with alcohol consumption prior to sex when both partners used alcohol, aPR = 1.15 (95 % CI 1.10-1.20) or when either one of them used alcohol aPR = 1.14 (95 % CI 1.09-1.18). These findings concur with previous literature suggesting a relationship between alcohol consumption prior to sex and STI and HIV. These data improve our understanding of this relationship in this context and could be used to enhance STI and HIV prevention strategies for socially marginalized men in Peru.
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In Peru, reporting male sex partners imparts significant risk of incident HIV/sexually transmitted infection: all men Engaging in same-sex behavior need prevention services.
Sex Transm Dis
PUBLISHED: 08-23-2013
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Detailed information on the sexual behavior of bisexual, non-gay-identified men and the relationship between same-sex behavior and HIV/sexually transmitted infection (STI) incidence is limited. This study provides information on the sexual behavior with male partners of non-gay-identified men in urban, coastal Peru and the relationship of this behavior with HIV/STI incidence.
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Novel Bartonella agent as cause of verruga peruana.
Emerging Infect. Dis.
PUBLISHED: 06-15-2013
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While studying chronic verruga peruana infections in Peru from 2003, we isolated a novel Bartonella agent, which we propose be named Candidatus Bartonella ancashi. This case reveals the inherent weakness of relying solely on clinical syndromes for diagnosis and underscores the need for a new diagnostic paradigm in developing settings.
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Detection of human leptospirosis as a cause of acute fever by capture ELISA using a Leptospira interrogans serovar Copenhageni (M20) derived antigen.
BMC Infect. Dis.
PUBLISHED: 04-06-2013
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Leptospirosis is a potentially lethal zoonosis mainly affecting low-resource tropical countries, including Peru and its neighbouring countries. Timely diagnosis of leptospirosis is critical but may be challenging in the regions where it is most prevalent. The serodiagnostic gold standard microagglutination test (MAT) may be technically prohibitive. Our objective in this study was to assess the sensitivity, specificity, and predictive value of an IgM antibody capture enzyme-linked immunoassay (MAC-ELISA) derived from the M20 strain of Leptospira interrogans serovar Copenhageni (M20) by comparison to MAT, which was used as the gold standard method of diagnosis.
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Prevalence of HIV, STIs, and risk behaviors in a cross-sectional community- and clinic-based sample of men who have sex with men (MSM) in Lima, Peru.
PLoS ONE
PUBLISHED: 01-01-2013
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Further research is necessary to understand the factors contributing to the high prevalence of HIV/STIs among men who have sex with men (MSM) in Peru. We compared HIV/STI prevalence and risk factors between two non-probability samples of MSM, one passively enrolled from an STI clinic and the other actively enrolled from community venues surrounding the clinic in Lima, Peru.
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Microfluidic capture and release of bacteria in a conical nanopore array.
Lab Chip
PUBLISHED: 12-14-2011
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We present a simple and inexpensive method for the capture and release of bacteria contained in an array of conical nanopores on a membrane inside a microfluidic device. As an example, we demonstrate that cyanobacteria can be captured, one bacterium per pore, in a defined orientation with over 500 bacteria per membrane with viabilities as high as 100%. The device can also specifically capture cyanobacteria from a mixed suspension of cyanobacteria and chlamydomonas with a selectivity as high as 90%.
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Microfluidic purification and analysis of hematopoietic stem cells from bone marrow.
Lab Chip
PUBLISHED: 07-29-2011
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Hematopoietic stem cells are larger in size than other cells present in bone marrow, with the exception of monocytes. This distinguishing characteristic can be used to separate them from a whole-marrow sample. A microfluidic device was fabricated using an integrated membrane that is porous at defined areas. This allows for simultaneous valving and filtering functionality, which is crucial for preventing irreversible clogging. This device, as well as a separation procedure, was optimized in this work to enrich hematopoietic progenitor cells from diluted bone marrow of leukemia patients without any additional sample preparation. An enrichment of up to 98% was achieved with this method and the process was scaled up to 17.2 ?L min(-1) of processed sample. Additionally, stem cells were stained with specific antibodies for further analysis. Using a custom-made computer program, the filter was scanned to characterize and quantify cells based on fluorescence. The results were evaluated by comparing them against the results obtained from flow cytometry, confocal microscopy, and Coulter counting.
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Production and characterization of foam in the anoxic zone of a membrane-enhanced biological phosphorus removal process.
Water Environ. Res.
PUBLISHED: 04-01-2011
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A pilot-scale membrane-enhanced biological phosphorus removal process accumulated substantial quantities of stable foam on the surface of the anoxic zone. The foam contained 4 to 6% dry matter, with specific nitrogen and phosphorus contents that were similar to those of the underlying anoxic zone mixed liquor. Kinetic studies demonstrated that the specific rate of phosphorus release from the foam was only 25 to 30% of that observed with mixed liquor from the aerobic zone. Molecular techniques demonstrated that the calculated similarity of the microbial communities in the foam and the underlying mixed liquor was approximately 80%, with two phylotypes (Gordonia amarae and Microthrix parvicella) being uniquely enriched in the foam and one phylotype (Epistylis sp.) more abundant in the underlying mixed liquor. The production of foam was demonstrated to be a consistent phenomenon that depended on the concentration of the suspended solids in the bioreactor.
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Viewing television shows containing ideal and neutral body images while exercising: does type of body image content influence exercise performance and body image in women?
J Health Psychol
PUBLISHED: 03-25-2011
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This study examined how exposure to media containing different body image content while exercising influenced exercise performance and feelings concerning appearance. 41 females completed two sessions of cycling (30 minutes). During exercise, participants viewed a television show that contained either media-portrayed ideal or neutral female body images. There were no differences in exercise performance between conditions. Physical appearance state anxiety (PASA) decreased post-exercise. After viewing ideal bodies, participants scored higher on appearance and comparison processing. The high internalization group scored higher on appearance and comparison processing and PASA increased following ideal body image content while the low internalization group decreased.
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Campylobacter spp. distribution in biofilms on different surfaces in an agricultural watershed (Elk Creek, British Columbia): using biofilms to monitor for Campylobacter.
Int J Hyg Environ Health
PUBLISHED: 03-07-2011
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Despite its relevance to public health, presence and concentrations of Campylobacter spp. in biofilms in natural aquatic environments has not been investigated. This study examined the occurrence of Campylobacter spp. in biofilms on a variety of surfaces (river rock, slate rock, wood, Lexan™, sandpaper, and sediment) and in water from December 2005 to December 2006 to find a substratum that facilitated campylobacters detection in natural aquatic environments. Samples were collected at four sites in an agricultural watershed (Elk Creek, British Columbia). Campylobacter spp. presence was determined using culturing methods. Correlations between chemical, physical and microbiological water quality parameters and Campylobacter spp. distribution on different surface types were also investigated. Campylobacter spp. had a prevalence of 13% in the wet season, but was not recovered in the dry season. Its prevalence was highest in sediment (27%), followed by slate rock (22%), Lexan and wood (13%), river rock (9%) and water (8%), respectively. No Campylobacter spp. was found in sandpaper biofilms. Several other criteria were used to assess substrata effectiveness, such as correlation amongst Campylobacter spp., indicator bacteria and water quality parameters, cost and availability of substratum, potential for standardizing substratum, ease of biofilm removal and probability of substratum loss in situ. Results show that sediment, slate rock or wood could be used as substrata for Campylobacter spp. monitoring. The study also highlights the potential use of nitrates and enterococci as faecal contamination indicators to protect public health.
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Antimicrobial susceptibility of Brucella melitensis isolates in Peru.
Antimicrob. Agents Chemother.
PUBLISHED: 01-03-2011
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Brucellosis is an important public health problem in Peru. We evaluated 48 human Brucella melitensis biotype 1 strains from Peru between 2000 and 2006. MICs of isolates to doxycycline, azithromycin, gentamicin, rifampin, ciprofloxacin, and trimethoprim-sulfamethoxazole were determined by the Etest method. All isolates were sensitive to tested drugs during the periods of testing. Relapses did not appear to be related to drug resistance.
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Managing radiation use in medical imaging: a multifaceted challenge.
Radiology
PUBLISHED: 12-16-2010
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This special report aims to inform the medical community about the many challenges involved in managing radiation exposure in a way that maximizes the benefit-risk ratio. The report discusses the state of current knowledge and key questions in regard to sources of medical imaging radiation exposure, radiation risk estimation, dose reduction strategies, and regulatory options.
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Detection of the CS20 colonization factor antigen in diffuse-adhering Escherichia coli strains.
FEMS Immunol. Med. Microbiol.
PUBLISHED: 11-11-2010
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We analyzed a randomly selected group of 30 diffusely adherent (DAEC), 30 enteropathogenic, 30 enteroaggregative, and five Shiga toxin-producing Escherichia coli strains isolated from children with diarrhea. Enterotoxigenic E. coli (ETEC) colonization factors (CFs) were evaluated by a dot-blot assay using 21 CF-specific monoclonal antibodies. Out of 95 non-ETEC strains, three DAEC were found to express coli surface antigen 20 (CS20). No other E. coli expressed CFs. We confirmed the three CS20-positive strains as ETEC-negative by repeat PCR and as toxin-negative by ganglioside-GM1-enzyme-linked immunosorbent assay. To our knowledge, this is the first study that has identified currently recognized CFs in non-ETEC diarrheagenic E. coli strains identified using molecular methods. CFs may be an unrecognized relevant adherence factor in other E. coli, which may then play a role in pathogenesis and the immune response of the host.
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Particle sorting using a porous membrane in a microfluidic device.
Lab Chip
PUBLISHED: 11-08-2010
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Porous membranes have been fabricated based on the development of the perforated membrane mold [Y. Luo and R. N. Zare, Lab Chip, 2008, 8, 1688-1694] to create a single filter that contains multiple pore sizes ranging from 6.4 to 16.6 µm inside a monolithic three-dimensional poly(dimethylsiloxane) microfluidic structure. By overlapping two filters we are able to achieve smaller pore size openings (2.5 to 3.3 µm). This filter operates without any detectable irreversible clogging, which is achieved using a cross-flow placed in front of each filtration section. The utility of a particle-sorting device that contains this filter is demonstrated by separating polystyrene beads of different diameters with an efficiency greater than 99.9%. Additionally, we demonstrate the effectiveness of this particle-sorting device by separating whole blood samples into white blood cells and red blood cells with platelets.
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The H63D HFE gene variant promotes activation of the intrinsic apoptotic pathway via mitochondria dysfunction following ?-amyloid peptide exposure.
J. Neurosci. Res.
PUBLISHED: 08-25-2010
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Numerous epidemiological studies suggest that the expression of the HFE allelic variant H63D may be a risk factor or genetic modifier for Alzheimers disease (AD). The H63D variant alters cellular iron homeostasis and increases baseline oxidative stress. The elevated cellular stress milieu, we have proposed, may alter cellular responses to genetic and environmental determinants of AD. Accumulation of ?-amyloid peptides (A?) is one of the most prominent pathogenic characteristics of AD. Several studies have demonstrated that A? can induce neuronal cell death through apoptosis. In this study, we provide evidence that an A?(25-35) fragment, which contains the cytotoxic sequence of the amyloid peptide, activates the intrinsic apoptotic pathway in SH-SY5Y human neuroblastoma cells expressing the HFE allelic variant H63D to a greater extent than in cells with wild-type (WT) HFE. Specifically, A?(25-35) peptide exposure significantly induced Bax translocation from the cytosol to the mitochondria in H63D-expressing cells compared with WT cells. This translocation was associated with increased cytochrome c release from mitochondria and an increase in active caspase-9 and caspase-3 activity in H63D cells. Consequently, there is increased apoptosis in cells expressing the H63D variant as opposed to cells expressing WT HFE. We also found increased amyloid precursor protein (APP) and A?(1-42) peptide in the mitochondrial compartment as well as increased mitochondrial stress in H63D-expressing cells compared with WT. These findings support our hypothesis that the presence of the HFE H63D allele enables factors that trigger neurodegenerative processes associated with AD and predisposes cells to cytotoxcity.
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Cognitive function during acute exercise: a test of the transient hypofrontality theory.
J Sport Exerc Psychol
PUBLISHED: 07-01-2010
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The purpose of this study was to test the transient hypofrontality theory (Dietrich, 2003) by examining the influence of exercise intensity on executive control processes during and following submaximal exercise. Thirty participants (13 female) exercised for 30 min at ventilatory threshold (VT) or at 75% of VT. The Contingent Continuous Performance Task (CPT) and Wisconsin Card Sorting Test (WCST) were used as measures of executive control. They were administered before, during, immediately following, and 20 min after exercise. An increase in false alarms and unique errors (p < or = .05) occurred during both conditions. False alarms for the CPT and total and perseverative errors for the WCST remained elevated immediately following exercise at VT, but not at exercise below VT (p < or = .01). The decreased executive control function during exercise can be explained by the transient hypofrontality theory. Following VT, executive control performance remained poor possibly owing to an additional amount of time the brain needs to return to homeostasis following intense exercise.
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The art of sharing the diagnosis and management of Alzheimers disease with patients and caregivers: recommendations of an expert consensus panel.
Prim Care Companion J Clin Psychiatry
PUBLISHED: 06-29-2010
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To develop a set of recommendations for primary care physicians (PCPs) suggesting how best to communicate with patients, caregivers, and other family members regarding the diagnosis and management of Alzheimers disease (AD).
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Hemizygosity for Atm and Brca1 influence the balance between cell transformation and apoptosis.
Radiat Oncol
PUBLISHED: 02-22-2010
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In recent years data from both mouse models and human tumors suggest that loss of one allele of genes involved in DNA repair pathways may play a central role in genomic instability and carcinogenesis. Additionally several examples in mouse models confirmed that loss of one allele of two functionally related genes may have an additive effect on tumor development. To understand some of the mechanisms involved, we examined the role of monoallelic loss or Atm and Brca1 on cell transformation and apoptosis induced by radiation.
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Proton vs carbon ion beams in the definitive radiation treatment of cancer patients.
Radiother Oncol
PUBLISHED: 01-22-2010
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Relative to X-ray beams, proton [(1)H] and carbon ion [(12)C] beams provide superior distributions due primarily to their finite range. The principal differences are LET, low for (1)H and high for (12)C, and a narrower penumbra of (12)C beams. Were (12)C to yield a higher TCP for a defined NTCP than (1)H therapy, would LET, fractionation or penumbra width be the basis?
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A comparison of bacterial populations in enhanced biological phosphorus removal processes using membrane filtration or gravity sedimentation for solids-liquid separation.
Water Res.
PUBLISHED: 01-17-2010
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In an earlier phase of this study, we compared the performances of pilot scale treatment systems operated in either a conventional enhanced biological phosphorus removal (CEBPR) mode, or a membrane enhanced biological phosphorus removal (MEBPR) mode. In the present investigation, we characterized the bacterial community populations in these processes during parallel operation with the same municipal wastewater feed. The objectives of the study were (1) to assess the similarity of the bacterial communities supported in the two systems over time, (2) to determine if distinct bacterial populations are associated with the MEBPR and CEBPR processes, and (3) to relate the dynamics of the community composition to changes in treatment process configuration and to treatment process performance. The characteristics of the bacterial populations were first investigated with ribosomal intergenic spacer analysis, or RISA. To further understand the bacterial population dynamics, important RISA phylotypes were isolated and identified through 16S RNA gene sequencing. The parallel MEBPR and CEBPR systems developed bacterial communities that were distinct. The CEBPR community appeared to exhibit greater diversity, and this may have been the primary reason why the CEBPR treatment train demonstrated superior functional stability relative to the MEBPR counterpart. Moreover, the more diverse bacterial population apparent in the CEBPR system was observed to be more dynamic than that of the MEBPR process. Several RISA bands were found to be characteristic of either the membrane or conventional biological system. In particular, the MEBPR configuration appeared to be selective for the slow-growing organism Magnospira bakii and for the foam-associated Microthrix parvicella and Gordonia sp., while gravity separation led to the washout of M. parvicella. In both pilot trains, sequence analysis confirmed the presence of EBPR-related organisms such as Accumulibacter phosphatis. The survey of the CEBPR system also revealed many uncultured organisms that have not been well characterized. The study demonstrated that a simple replacement of a secondary clarifier with membrane solids-liquid separation is sufficient to shift the composition of an activated sludge microbial community significantly.
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Prolyl-peptidyl isomerase, Pin1, phosphorylation is compromised in association with the expression of the HFE polymorphic allele, H63D.
Biochim. Biophys. Acta
PUBLISHED: 01-05-2010
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There is substantial interest in HFE gene variants as putative risk factors in neurodegenerative diseases such as Alzheimer disease (AD). Previous studies in cell models have shown the H63D HFE variant to result in increased cellular iron, oxidative stress, glutamate dyshomeostasis, and an increase in tau phosphorylation; all processes thought to contribute to AD pathology. Pin1 is a prolyl-peptidyl cis/trans isomerase that can regulate the dephosphorylation of the amyloid and tau proteins. Hyperphosphorylation of these later proteins is implicated in the pathogenesis of AD and Pin1 levels are reportedly decreased in AD brains. Because of the relationship between Pin1 loss of function by oxidative stress and the increase in oxidative stress in cells with the H63D polymorphism it was logical to interrogate a relationship between Pin1 and HFE status. To test our hypothesis that H63D HFE would be associated with less Pin1 activity, we utilized stably transfected human neuroblastoma SH-SY5Y cell lines expressing the different HFE polymorphisms. Under resting conditions, total Pin1 levels were unchanged between the wild type and H63D HFE cells, yet there was a significant increase in phosphorylation of Pin1 at its serine 16 residue suggesting a loss of Pin1 activity in H63D variant cells. To evaluate whether cellular iron status could influence Pin1, we treated the WT HFE cells with exogenous iron and found that Pin1 phosphorylation increased with increasing levels of iron. Iron exposure to H63D variant cells did not impact Pin1 phosphorylation beyond that already seen suggesting a ceiling effect. Because HFE H63D cells have been shown to have more oxidative stress, the cells were treated with the antioxidant Trolox which resulted in a decrease in Pin1 phosphorylation in H63D cells with no change in WT HFE cells. In a mouse model carrying the mouse equivalent of the H63D allele, there was an increase in the phosphorylation status of Pin1 providing in vivo evidence for our findings in the cell culture model. Thus, we have shown another cellular mechanism that HFE polymorphisms influence; further supporting their role as neurodegenerative disease modifiers.
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Predicting affective responses to exercise using resting EEG frontal asymmetry: does intensity matter?
Biol Psychol
PUBLISHED: 01-02-2010
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Affective responses to exercise may be important for improving adherence to regular programs of exercise. The present study sought to determine whether resting frontal EEG asymmetry, an individual difference measure of affective style, is predictive of affective responses to exercise performed at distinct intensities standardized relative to a metabolic landmark (i.e., the ventilatory threshold, VT). Resting EEG was collected from 30 participants and used to predict affective responses following treadmill running at three exercise intensities: below-VT, at-VT, and above-VT. Affect was assessed [via Activation-Deactivation Adjective Check List, yielding measures of Energetic Arousal (EA) and Tense Arousal (TA)] before, immediately following exercise, after 5min cool down, and 10 and 20min post-cool down. Resting mid-frontal asymmetry (F4-F3) significantly predicted EA immediately following below-VT exercise; resting lateral frontal asymmetry (F8-F7) predicted EA at 20min post-cool down. Resting mid-frontal asymmetry predicted in EA immediately following and following cool down in above-VT exercise. As a whole, frontal asymmetry was predictive of affective responses following exercise, namely greater relative left frontal activity predicting lower EA. This was opposite to the predictions of the valenced motivation model, but may provide some support for the motivation direction model. This is based on the fact that low EA could be indicative of approach motivation, especially at higher exercise intensities.
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Mirrors and resistance exercise, do they influence affective responses?
J Health Psychol
PUBLISHED: 10-28-2009
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The purpose of this study was to examine affective responses during and following resistance exercise in a mirrored environment. Thirty-two females completed three sessions. During session one, exercise intensity was determined for the subsequent two sessions. During the next two sessions participants performed eight exercises either with or without mirrors. Affect was measured prior to, during, immediately following and 15 minutes post-exercise. Affect was more pleasant and activated during and following exercise, but did not differ by condition. The inability to find a difference in mirrored condition may be a result of participants using the mirrors for technique as opposed to self-evaluation purposes.
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Age-related susceptibility to infection with diarrheagenic Escherichia coli among infants from Periurban areas in Lima, Peru.
Clin. Infect. Dis.
PUBLISHED: 10-28-2009
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Diarrheagenic Escherichia coli strains are being recognized as important pediatric enteropathogens worldwide. However, it is unclear whether there are differences in age-related susceptibility to specific strains, especially among infants.
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Reduction of the secondary neutron dose in passively scattered proton radiotherapy, using an optimized pre-collimator/collimator.
Phys Med Biol
PUBLISHED: 09-24-2009
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Proton radiotherapy represents a potential major advance in cancer therapy. Most current proton beams are spread out to cover the tumor using passive scattering and collimation, resulting in an extra whole-body high-energy neutron dose, primarily from proton interactions with the final collimator. There is considerable uncertainty as to the carcinogenic potential of low doses of high-energy neutrons, and thus we investigate whether this neutron dose can be significantly reduced without major modifications to passively scattered proton beam lines. Our goal is to optimize the design features of a patient-specific collimator or pre-collimator/collimator assembly. There are a number of often contradictory design features, in terms of geometry and material, involved in an optimal design. For example, plastic or hybrid plastic/metal collimators have a number of advantages. We quantify these design issues, and investigate the practical balances that can be achieved to significantly reduce the neutron dose without major alterations to the beamline design or function. Given that the majority of proton therapy treatments, at least for the next few years, will use passive scattering techniques, reducing the associated neutron-related risks by simple modifications of the collimator assembly design is a desirable goal.
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Molecular epidemiology of Brucella genotypes in patients at a major hospital in central Peru.
J. Clin. Microbiol.
PUBLISHED: 08-05-2009
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The multiple-locus variable-number repeat analysis of 90 human Brucella melitensis isolates from a large urban area in central Peru revealed variations at 4 (Bruce07, Bruce09, Bruce18, and Bruce42) out of 16 loci investigated, of which 1 (Bruce42) also is used for species identification. Ten genotypes were identified, separated by the number of Bruce42 repeats into two groups that may have distinct phenotypic characteristics. Whereas genotypes with five or six Bruce42 repeats were cultured mainly from adult patients, genotypes with three Bruce42 repeats were isolated from children and young adolescents as well as from adults. In addition, the isolates with three Bruce42 repeats were obtained more often from patients with splenomegaly (P = 0.02) or hepatomegaly (P = 0.006). An annual variation in the diversity of genotypes was observed, possibly reflecting changes in sources of fresh dairy products, supply routes to city shops and markets, and the movement of infected dairy goat herds.
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Norovirus highly prevalent cause of endemic acute diarrhea in children in the peruvian Amazon.
Pediatr. Infect. Dis. J.
PUBLISHED: 07-29-2009
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To determine the burden of norovirus infections in children stools from a longitudinal community cohort were evaluated using reverse transcription polymerase chain reaction. Norovirus was detected in 21.3% of diarrheal and 8.0% of nondiarrheal stools (P < 0.01). Norovirus diarrhea was highly associated with age and the odds ratio for norovirus diarrhea fell by 2.8% per month (OR = 0.97, 95% CI: 0.95-0.99). Norovirus seems to be an important etiology of community acquired diarrhea in this study population.
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High frequency of antimicrobial drug resistance of diarrheagenic Escherichia coli in infants in Peru.
Am. J. Trop. Med. Hyg.
PUBLISHED: 07-29-2009
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In a prospective passive diarrhea surveillance cohort study of 1,034 infants of low socioeconomic communities in Lima, Peru, we determined the prevalence and antimicrobial drug susceptibility of the diarrheagenic Escherichia coli . The prevalence of diarrheagenic E. coli was 29% (161 of 557) in children with gastroenteritis and 30% (58 of 195) in the control group without diarrhea. The most common E. coli pathogens in diarrhea were enteroaggregative E. coli (EAEC) (14%), enteropathogenic E. coli (EPEC) (7%), diffusely adherent E. coli (DAEC) (4%), and enterotoxigenic E. coli (ETEC) (4%). Diarrheagenic E. coli as a group exhibited high levels of antimicrobial drug resistance in diarrheal cases to ampicillin (85%), cotrimoxazole (79%), tetracycline (65%), and nalidixic acid (28%). Among individual E. coli groups in patients with diarrhea, DAEC and EAEC exhibited significant higher frequencies of resistance to ampicillin, cotrimoxazole, tetracycline and nalidixic acid than EPEC and ETEC. Antimicrobial drug resistance to ampicillin and cotrimoxazole were more frequent in E. coli isolated from diarrheal samples than controls, which reflected greater antibiotic exposure in patients with gastroenteritis.
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MLVA genotyping of human Brucella isolates from Peru.
Trans. R. Soc. Trop. Med. Hyg.
PUBLISHED: 07-28-2009
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Recent human Brucella melitensis isolates from Peru were genotyped by multiple locus variable number repeat analysis. All 24 isolates originated from hospitalized patients living in the central part of Peru and consisted of six genomic groups comprising two to four isolates and nine unique genotypes. The isolates were most closely related to the two previously genotyped isolates from Mexico, with a maximum distance of 2 to 4. The Peruvian strains were clearly distinct from the East and West Mediterranean groups of B. melitensis genotypes, suggesting that they may constitute a unique Latin American cluster.
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Is there a place for quantitative risk assessment?
J Radiol Prot
PUBLISHED: 05-19-2009
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The use of ionising radiations is so well established, especially in the practice of medicine, that it is impossible to imagine contemporary life without them. At the same time, ionising radiations are a known and proven human carcinogen. Exposure to radiation in some contexts elicits fear and alarm (nuclear power for example) while in other situations, until recently at least, it was accepted with alacrity (diagnostic x-rays for example). This non-uniform reaction to the potential hazards of radiation highlights the importance of quantitative risk estimates, which are necessary to help put things into perspective. Three areas will be discussed where quantitative risk estimates are needed and where uncertainties and limitations are a problem. First, the question of diagnostic x-rays. CT usage over the past quarter of a century has increased about 12 fold in the UK and more than 20 fold in the US. In both countries, more than 90% of the collective population dose from diagnostic x-rays comes from the few high dose procedures, such as interventional radiology, CT scans, lumbar spine x-rays and barium enemas. These all involve doses close to the lower limit at which there are credible epidemiological data for an excess cancer incidence. This is a critical question; what is the lowest dose at which there is good evidence of an elevated cancer incidence? Without low dose risk estimates the risk-benefit ratio of diagnostic procedures cannot be assessed. Second, the use of new techniques in radiation oncology. IMRT is widely used to obtain a more conformal dose distribution, particularly in children. It results in a larger total body dose, due to an increased number of monitor units and to the application of more radiation fields. The Linacs used today were not designed for IMRT and are based on leakage standards that were decided decades ago. It will be difficult and costly to reduce leakage from treatment machines, and a necessary first step is to refine the available radiation risks at the fractionated high doses characteristic of radiotherapy. The dose response for carcinogenesis is known for single doses up to about 2 Sv from the A-bomb data, but the shape at higher fractionated doses is uncertain. Third, the proliferation of proton facilities. The improved dose distribution made possible by charged particle beams has created great interest and led to the design and building of many expensive proton centres. However, due to technical problems, most facilities use passive scattering, rather than spot scanning, to spread the pencil beam to cover realistic target volumes. This process, together with the methods used of final collimation, results in substantial total body doses of neutrons. The relative biological effectiveness of these neutrons is not well known, and the risk estimates are therefore uncertain. Unless and until the risks are known with more certainty, it is difficult to know how much effort and cost should be directed towards reducing, or eliminating, the neutron doses. These three examples, where uncertainties in quantitative risk estimates result in important practical problems, will be discussed.
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Comparison of culture techniques at different stages of brucellosis.
Am. J. Trop. Med. Hyg.
PUBLISHED: 04-07-2009
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The lysis centrifugation technique is preferred for culturing Brucella spp. at all stages of brucellosis because it yields 25% more positive results and on average provides results 10 days earlier than the Ruiz-Castaneda method. This lysis method is inexpensive and easier to use and may be used in laboratories with limited expertise or equipment if all safety precautions are taken.
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Radiation biology for pediatric radiologists.
Pediatr Radiol
PUBLISHED: 04-01-2009
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The biological effects of radiation result primarily from damage to DNA. There are three effects of concern to the radiologist that determine the need for radiation protection and the dose principle of ALARA (As Low As Reasonably Achievable). (1) Heritable effects. These were thought to be most important in the 1950s, but concern has declined in recent years. The current ICRP risk estimate is very small at 0.2%/Sv. (2) Effects on the developing embryo and fetus include weight retardation, congenital anomalies, microcephaly and mental retardation. During the sensitive period of 8 to 15 weeks of gestation, the risk estimate for mental retardation is very high at 40%/Sv, but because it is a deterministic effect, there is likely to be a threshold of about 200 mSv. (3) Carcinogenesis is considered to be the most important consequence of low doses of radiation, with a risk of fatal cancer of about 5%/Sv, and is therefore of most concern in radiology. Our knowledge of radiation carcinogenesis comes principally from the 60-year study of the A-bomb survivors. The use of radiation for diagnostic purposes has increased dramatically in recent years. The annual collective population dose has increased by 750% since 1980 to 930,000 person Sv. One of the principal reasons is the burgeoning use of CT scans. In 2006, more than 60 million CT scans were performed in the U.S., with about 6 million of them in children. As a rule of thumb, an abdominal CT scan in a 1-year-old child results in a life-time mortality risk of about one in a thousand. While the risk to the individual is small and acceptable when the scan is clinically justified, even a small risk when multiplied by an increasingly large number is likely to produce a significant public health concern. It is for this reason that every effort should be made to reduce the doses associated with procedures such as CT scans, particularly in children, in the spirit of ALARA.
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Capsule polysaccharide conjugate vaccine against diarrheal disease caused by Campylobacter jejuni.
Infect. Immun.
PUBLISHED: 03-20-2009
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The capsule polysaccharide (CPS) of Campylobacter jejuni is one of the few identified virulence determinants of this important human pathogen. Since CPS conjugate vaccines have been so effective against other mucosal pathogens, we evaluated this approach using CPSs from two strains of C. jejuni, 81-176 (HS23 and HS36 serotype complex) and CG8486 (HS4 serotype complex). The CPSs of 81-176 and CG8486 were independently linked to the carrier protein CRM(197) by reductive amination between an aldehyde(s), strategically created at the nonreducing end of each CPS, and accessible amines of CRM(197). In both cases, the CPS:CRM(197) ratio used was 2:1 by weight. Mass spectrometry and gel electrophoresis showed that on average, each glycoconjugate preparation contained, at least in part, two to five CPSs attached to one CRM(197). When administered subcutaneously to mice, these vaccines elicited robust immune responses and significantly reduced the disease following intranasal challenge with the homologous strains of C. jejuni. The CPS(81-176)-CRM(197) vaccine also provided 100% protection against diarrhea in the New World monkey Aotus nancymaae following orogastric challenge with C. jejuni 81-176.
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Primary human hepatocyte culture for HCV study.
Methods Mol. Biol.
PUBLISHED: 03-07-2009
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Studies of HCV pathogenesis and antiviral research have been hampered by the lack of adequate cell-culture and small-animal models. The culturing of human primary hepatocytes would greatly facilitate the model development in HCV research. The availability of robust infectious virus, JFH1 (i.e., genotype 2) strain, will further increase the interest in using primary hepatocyte cultures. This cell model system will significantly enhance research in the areas of antiviral research and host-virus interaction, but obtaining pure and viable human primary hepatocytes is not trivial. We have optimized a method of liver perfusion and primary hepatocyte isolation that allows us to establish robust and reliable human primary hepatocyte cultures. Moreover, we have demonstrated that these primary cultures are susceptible to authentic HCV infection in vitro.
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Wastewater treatment models in teaching and training: the mismatch between education and requirements for jobs.
Water Sci. Technol.
PUBLISHED: 02-25-2009
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As mathematical modeling of wastewater treatment plants has become more common in research and consultancy, a mismatch between education and requirements for model-related jobs has developed. There seems to be a shortage of skilled people, both in terms of quantity and in quality. In order to address this problem, this paper provides a framework to outline different types of model-related jobs, assess the required skills for these jobs and characterize different types of education that modelers obtain "in school" as well as "on the job". It is important to consider that education of modelers does not mainly happen in university courses and that the variety of model related jobs goes far beyond use for process design by consulting companies. To resolve the mismatch, the current connection between requirements for different jobs and the various types of education has to be assessed for different geographical regions and professional environments. This allows the evaluation and improvement of important educational paths, considering quality assurance and future developments. Moreover, conclusions from a workshop involving practitioners and academics from North America and Europe are presented. The participants stressed the importance of non-technical skills and recommended strengthening the role of realistic modeling experience in university training. However, this paper suggests that all providers of modeling education and support, not only universities, but also software suppliers, professional associations and companies performing modeling tasks are called to assess and strengthen their role in training and support of professional modelers.
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Expression of the HFE allelic variant H63D in SH-SY5Y cells affects tau phosphorylation at serine residues.
Neurobiol. Aging
PUBLISHED: 02-11-2009
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A number of genetic association studies have appeared that address HFE gene variants in neurodegenerative disorders. However, the cellular impact of HFE in the nervous system has received little attention. To begin to address the role of the HFE allelic variants on cellular events associated with neurodegeneration, we examined the hypothesis that HFE polymorphisms are associated with alterations in tau phosphorylation in a human neuroblastoma cell line (SH-SY5Y). The results show that in a cell culture model, the H63D allele is associated with increased tau phosphorylation. The mechanisms responsible for these changes appear related to increased glycogen synthase kinase (GSK)-3? activity. GSK-3? activity is up-regulated in the cells expressing H63D HFE and can be modified by the addition of iron or treatment with an iron chelator in SH-SY5Y cells expressing wild-type HFE. Oxidative stress, also associated with elevated cellular iron, is associated with increased tau phosphorylation at the same sites as seen in H63D cells and treatment with Trolox, an anti-oxidant, lowered tau phosphorylation. These results suggest H63D HFE increases tau phosphorylation via GSK-3? activity and iron-mediated oxidative stress.
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The influence of muscle action on heart rate, RPE, and affective responses after upper-body resistance exercise.
J Strength Cond Res
PUBLISHED: 02-11-2009
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Ratings of perceived exertion (RPE) are routinely used to monitor, assess, and prescribe aerobic exercise. Heart rate (HR) is another measure used to evaluate exercise intensity. Additionally, affective responses to aerobic exercise have been studied and seem to be influenced by the intensity of the exercise. The perceptual, HR, and affective responses to resistance exercise have not been effectively established. The purpose of this study was to examine whether differences in affect, RPE, and HR exist among college-aged women (n = 31) performing three different modes of resistance training: concentric (CE), eccentric (EE), and traditional concentric/eccentric (TE) performed at varying resistances. The women were asked to complete four sessions of resistance training on variable resistance machines: chest press, seated row, overhead press, and biceps curl. The first session was used to establish the 10-repetition maximum (RM) load for each station. Subsequent sessions involved the execution of training in one of the three test conditions: CE, EE, or TE. The participants performed three sets of each lift at 80% 10-RM, 100% 10-RM, and 120% 10-RM. The data revealed lower RPE during EE than the other test conditions. Similarly, EE elicited more mild HR response than either CE or TE. This finding is potentially important for the establishment of training programs, especially for those individuals recovering from an illness, who had been previously sedentary, and who are involved in rehabilitation of an injury.
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Patient-level analysis of outcomes using structured labor and delivery data.
J Biomed Inform
PUBLISHED: 01-30-2009
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This paper presents methods for identifying and analyzing associations among nursing care processes, patient attributes, and patient outcomes using unit-level and patient-level representations of care derived from computerized nurse documentation. The retrospective, descriptive analysis included documented nursing events for 900 Labor and Delivery patients at three hospitals over the 2-month period of January and February 2006. Two models were used to produce quantified measurements of nursing care received by each patient. The first model considered only the hourly census of nurses and patients. The second model considered the size of nurses patient loads as represented by computerized nurse-entered documentation. Significant relationships were identified between durations of labor and nursing care scores generated by the second model. In addition to the clinical associations identified, the study demonstrated an approach with global application for representing the amount of nursing care received at the individual patient level in analyses of patient outcomes.
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The influence of exercise order on blood lactate, perceptual, and affective responses.
J Strength Cond Res
PUBLISHED: 01-09-2009
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The purpose of this study was to examine the influence of exercise order on blood lactate, perceptual, and affective responses to resistance exercise. Twenty-nine subjects (18 women, 11 men; 20.9 +/- 1.9 years) completed three sessions separated by a minimum of 48 hours. Session 1 determined the 10-repetition maximum (10RM) for nine resistance exercises. During sessions 2 and 3, exercises were completed in either a large to small or small to large muscle exercise order. The large to small muscle order was 1) chest press, 2) leg press, 3) rows, 4) leg extension, 5) overhead press, 6) hamstring curl, 7) biceps curl, 8) calve raise, and 9) triceps extension. Exercise order was reversed for the small to large condition. Participants performed two sets of each lift, with the first set being a warm-up at 80% 10RM, followed by one set at 100% 10RM with 1 minute of rest between each exercise. Rating of perceived exertion (RPE) was measured after completion of the second set. Blood lactate was recorded after exercises 1, 5, and 9. Affective measures were completed pre, during, post 0, and post 10 minutes. Lactate showed a significant time (p < 0.001) and condition x time interaction (p = 0.020). A significant difference was seen in average number of repetitions completed between sequences, with small to large performing more. There were no differences seen between exercise orders for average RPE. Analyses of Feeling Scale and Felt Arousal Scale scores showed only a significant main effect of time. A paired-sample t-test was conducted to examine differences in Feeling Scale for the two conditions at the different time points. Significant differences were found for Feeling Scale during exercise (after overhead press) and at post 10, with the small to large exercise order having greater Feeling Scale responses. No significant correlations were seen between blood lactate and perceptual or affective responses at any time point or in either exercise order. These findings may suggest that small to large exercise order may have beneficial physiological and psychological outcomes and potentially influence exercise adherence.
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Spatial analysis in support of community health intervention strategies.
AMIA Annu Symp Proc
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Using vital records and census data representing 165,136 singleton births from 2003-2006, geospatial filtering and density estimates enabled the calculation of preterm birth rates at each geographical point within three urban Ohio counties. Adjusted attributable risk calculations were used to identify risk factors associated with regions of high and low rates of preterm birth. Among the three counties, affected populations varied in size as well as in demographic composition. Variation in the risk factors from one region to another suggests that a single one size fits all intervention strategy would be unlikely to efficiently or effectively impact the complex preterm birth problem. Although more useful in areas with a heterogeneous distribution of preterm birth, application of the presented approach supports the development of efficient community-level health intervention strategies by identifying communities with the highest potential impact and allowing for the prioritization of efforts on specific risk factors within those communities.
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Phenotypic antibiotic resistance of Escherichia coli and E. coli O157 isolated from water, sediment and biofilms in an agricultural watershed in British Columbia.
Sci. Total Environ.
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This study examined the distribution of antibiotic resistant Escherichia coli and E. coli O157 isolated from water, sediment and biofilms in an intensive agricultural watershed (Elk Creek, British Columbia) between 2005 and 2007. It also examined physical and chemical water parameters associated with antibiotic resistance. Broth microdilution techniques were used to determine minimum inhibitory concentrations (MIC) for E. coli (n=214) and E. coli O157 (n=27) recovered isolates for ampicillin, cefotaxime, ciprofloxacin, nalidixic acid, streptomycin and tetracycline. Both E. coli and E. coli O157 isolates showed highest frequency of resistance to tetracycline, ampicillin, streptomycin and nalidixic acid; respectively. For E. coli, the highest frequency of resistance was observed at the most agriculturally-impacted site, while the lowest frequency of resistance was found at the headwaters. Sediment and river rock biofilms were the most likely to be associated with resistant E. coli, while water was the least likely. While seasonality (wet versus dry) had no relationship with resistance frequency, length of biofilm colonization of the substratum in the aquatic environment only affected resistance frequency to nalidixic acid and tetracycline. Multivariate logistic regressions showed that water depth, nutrient concentrations, temperature, dissolved oxygen and salinity had statistically significant associations with frequency of E. coli resistance to nalidixic acid, streptomycin, ampicillin and tetracycline. The results indicate that antibiotic resistant E. coli and E. coli O157 were prevalent in an agricultural stream. Since E. coli is adept at horizontal gene transfer and prevalent in biofilms and sediment, where ample opportunities for genetic exchange with potential environmental pathogens present themselves, resistant isolates may present a risk to ecosystem, wildlife and public health.
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Campylobacter antimicrobial resistance in Peru: a ten-year observational study.
BMC Infect. Dis.
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Campylobacter jejuni and Campylobacter coli are food-borne pathogens of great importance and feature prominently in the etiology of developing world enteritis and travellers diarrhoea. Increasing antimicrobial resistant Campylobacter prevalence has been described globally, yet data from Peru is limited. Our objective was to describe the prevalence trends of fluoroquinolone and macrolide-resistant C. jejuni and C. coli stool isolates from three regions in Peru over a ten-year period.
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Facilitated molecular typing of Shigella isolates using ERIC-PCR.
Am. J. Trop. Med. Hyg.
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To evaluate the performance of enterobacterial repetitive intergenic sequence-based polymerase chain reaction (ERIC-PCR) typing versus the current standard for the typing of Shigella pulsed gel electrophoresis (PFGE), we typed 116 Shigella isolates from a village in an endemic setting over a 20-month period using both methods. PFGE identified 37 pulse types and had a discrimination index of 0.925 (95% confidence interval = 0.830-1.00), whereas ERIC-PCR identified 42 types and had a discrimination index of 0.961 (95% confidence interval = 0.886-1.00). PFGE and ERIC-PCR showed a 90.4% correlation in the designation of isolates as clonal or non-clonal in pairwise comparisons. Both systems were highly reproducible and provided highly similar and supplementary data compared with serotyping regarding the transmission dynamics of shigellosis in this community. ERIC-PCR is considerably more rapid and inexpensive than PFGE and may have a complementary role to PFGE for initial investigations of hypothesized outbreaks in resource-limited settings.
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Combined haploinsufficiency and genetic control of the G2/M checkpoint in irradiated cells.
Radiat. Res.
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When cells are exposed to a dose of radiation large enough to cause chromosome aberrations, they become arrested at the G(2)/M checkpoint, facilitating DNA repair. Defects in checkpoint control genes can impart radiosensitivity. Arrest kinetics were monitored in mouse embryo fibroblasts at doses ranging from 10 mGy to 5.0 Gy of ? radiation over a time course of 0 to 12 h. We observe no significant checkpoint engagement at doses below 100 mGy. The checkpoint is only fully activated at doses where most of the cells are either bound for mitotic catastrophe or are reproductively dead. Atm null cells with ablated checkpoint function exhibited no robust arrest. Surprisingly, haploinsufficiency for ATM alone or in combination with other radioresistance genes did not alter checkpoint activation. We have shown previously that haploinsufficiency for several radioresistance genes imparts intermediate phenotypes for several end points including apoptosis, transformation and survival. These findings suggest that checkpoint control does not contribute toward these intermediate phenotypes and that different biological processes can be activated at high doses compared to low doses.
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Separation of bacteria with imprinted polymeric films.
Analyst
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Separation of compounds out of complex mixtures is a key issue that has been solved for small molecules by chromatography. However, general methods for the separation of large bio-particles, such as cells, are still challenging. We demonstrate integration of imprinted polymeric films (IPF) into a microfluidic chip, which preferentially capture cells matching an imprint template, and separate strains of cyanobacteria with 80-90% efficiency, despite a minimal difference in morphology and fluorescence, demonstrating its general nature. It is currently thought that the imprinting process, conducted while the polymer cures, transfers chemical information of the cells external structure to the substrate. Capture specificity and separation can be further enhanced by orienting the imprints parallel to the flow vector and tuning the pH to a lower range.
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Evaluation of Gestational Age Estimate Method on the Calculation of Preterm Birth Rates.
Matern Child Health J
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The objectives of this study is to evaluate the impact of vital record gestational age estimation method on resulting preterm birth (PTB) rate calculations. This retrospective analysis reviewed three methods of gestational age estimation using all Ohio live birth records from 2006 to 2009. PTB rates were calculated using each gestational age representation and agreement between classifications of PTB was evaluated with respect to maternal age and race. For each of 608,530 births, gestational age estimates based on last menstrual period (LMP) were compared to clinically-based obstetric estimates. When gestational age estimates did not perfectly agree, differences in the consequential classification of PTB status were evaluated with respect to a third reconciliatory combined gestational age estimate. Mean birth weight at each week of gestation was calculated and compared for all three estimate methods. Substantial agreement was found in PTB classification among gestational age estimates (kappa: 0.748; 95 % Confidence Interval: 0.745-0.750); agreement was weakest among black mothers and among mothers less than 20 years of age. LMP-based gestational age estimates did not perfectly agree with obstetric estimates in 238,262 records (39.2 %). Disagreement in gestational age led to disagreement in PTB status in 32,033 records (5.3 % of total cases) resulting in a 1.8 percentage point difference in PTB rate calculations (11.0 % using obstetric and 12.8 % using combined estimates). Researchers and policy makers need consistency in selecting which gestational age estimate method to use when calculating or comparing PTB rates.
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Development of a Linked Perinatal Data Resource From State Administrative and Community-Based Program Data.
Matern Child Health J
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To demonstrate a generalizable approach for developing maternal-child health data resources using state administrative records and community-based program data. We used a probabilistic and deterministic linking strategy to join vital records, hospital discharge records, and home visiting data for a population-based cohort of at-risk, first time mothers enrolled in a regional home visiting program in Southwestern Ohio and Northern Kentucky from 2007 to 2010. Because data sources shared no universal identifier, common identifying elements were selected and evaluated for discriminating power. Vital records then served as a hub to which other records were linked. Variables were recoded into clinically significant categories and a cross-set of composite analytic variables was constructed. Finally, individual-level data were linked to corresponding area-level measures by census tract using the American Communities Survey. The final data set represented 2,330 maternal-infant pairs with both home visiting and vital records data. Of these, 56 pairs (2.4 %) did not link to either maternal or infant hospital discharge records. In a 10 % validation subset (n = 233), 100 % of the reviewed matches between home visiting data and vital records were true matches. Combining multiple data sources provided more comprehensive details of perinatal health service utilization and demographic, clinical, psychosocial, and behavioral characteristics than available from a single data source. Our approach offers a template for leveraging disparate sources of data to support a platform of research that evaluates the timeliness and reach of home visiting as well as its association with key maternal-child health outcomes.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.