115 research outputs found

    Special needs education in the blind population: effects of prior expertise in raised line drawings on blind people's cognition

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    AbstractIn their specialized schooling, blind children are now frequently presented with raised line figures and maps. However there is still a lot to do to evaluate the cognitive effects of training using these displays. The purpose of this research is to determine if the level of prior expertise in the haptic exploration and perception of raised line materials, may enhance blind people's spatial imagery. We observed that in the three spatial tasks used in this study, the congenitally blind experts performed better than the early and late blind non experts and the early blind experts performed even better than the late blind non experts. These observations suggested that a high level of expertise in congenitally and early blind people may compensate for the impairment in spatial representation often resulting from lack of visual experience

    Dietary intake relative to cardiovascular disease risk factors in individuals with chronic spinal cord injury: a pilot study

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    BACKGROUND: The relationship between cardiovascular disease (CVD) risk factors and dietary intake is unknown among individuals with spinal cord injury (SCI). OBJECTIVE: To investigate the relationship between consumption of selected food groups (dairy, whole grains, fruits, vegetables, and meat) and CVD risk factors in individuals with chronic SCI. METHODS: A cross-sectional substudy of individuals with SCI to assess CVD risk factors and dietary intake in comparison with age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Dietary history, blood pressure, waist circumference (WC), fasting blood glucose, high-sensitivity C-reactive protein (hs-CRP), lipids, glucose, and insulin data were collected from 100 SCI participants who were 38 to 55 years old with SCI >1 year and compared to 100 matched control participants from the CARDIA study. RESULTS: Statistically significant differences between SCI and CARDIA participants were identified in WC (39.2 vs 36.2 in.; P < .001) and high-density lipoprotein cholesterol (HDL-C; 39.2 vs 47.5 mg/dL; P < .001). Blood pressure, total cholesterol, triglycerides, glucose, insulin, and hs-CRP were similar between SCI and CARDIA participants. No significant relation between CVD risk factors and selected food groups was seen in the SCI participants. CONCLUSION: SCI participants had adverse WC and HDL-C compared to controls. This study did not identify a relationship between consumption of selected food groups and CVD risk factors

    Temperature controlled high-throughput magnetic tweezers show striking difference in activation energies of replicating viral RNA-dependent RNA polymerases

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    RNA virus survival depends on efficient viral genome replication, which is performed by the viral RNA dependent RNA polymerase (RdRp). The recent development of high throughput magnetic tweezers has enabled the simultaneous observation of dozens of viral RdRp elongation traces on kilobases long templates, and this has shown that RdRp nucleotide addition kinetics is stochastically interrupted by rare pauses of 1-1000 s duration, of which the short-lived ones (1-10 s) are the temporal signature of a low fidelity catalytic pathway. We present a simple and precise temperature controlled system for magnetic tweezers to characterize the replication kinetics temperature dependence between 25 degrees C and 45 degrees C of RdRps from three RNA viruses, i.e. the double-stranded RNA bacteriophage Phi 6, and the positive-sense single-stranded RNA poliovirus (PV) and human rhinovirus C (HRV-C). We found that Phi 6 RdRp is largely temperature insensitive, while PV and HRV-C RdRps replication kinetics are activated by temperature. Furthermore, the activation energies we measured for PV RdRp catalytic state corroborate previous estimations from ensemble pre-steady state kinetic studies, further confirming the catalytic origin of the short pauses and their link to temperature independent RdRp fidelity. This work will enable future temperature controlled study of biomolecular complex at the single molecule level.Peer reviewe

    Surveillance of health status in minority communities - Racial and Ethnic Approaches to Community Health Across the U.S. (REACH U.S.) Risk Factor Survey, United States, 2009.

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    PROBLEM: Substantial racial/ethnic health disparities exist in the United States. Although the populations of racial and ethnic minorities are growing at a rapid pace, large-scale community-based surveys and surveillance systems designed to monitor the health status of minority populations are limited. CDC conducts the Racial and Ethnic Approaches to Community Health across the U.S. (REACH U.S.) Risk Factor Survey annually in minority communities. The survey focuses on black, Hispanic, Asian (including Native Hawaiian and Other Pacific Islander), and American Indian (AI) populations. REPORTING PERIOD COVERED: 2009. DESCRIPTION OF SYSTEM: An address-based sampling design was used in the survey in 28 communities located in 17 states (Arizona, California, Georgia, Hawaii, Illinois, Massachusetts, Michigan, New Mexico, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Virginia, West Virginia, and Washington). Self-reported data were collected through telephone, questionnaire mailing, and in-person interviews from an average of 900 residents aged ≥ 18 years in each community. Data from the community were compared with data derived from the Behavioral Risk Factor Surveillance System (BRFSS) for the metropolitan and micropolitan statistical area (MMSA), county, or state in which the community was located and also compared with national estimates. RESULTS: Reported education level and household income were markedly lower in black, Hispanic, and AI communities than that among the general population living in the comparison MMSA, county, or state. More residents in these minority populations did not have health-care coverage and did not see a doctor because of the cost. Substantial variations were identified in self-perceived health status and prevalence of selected chronic conditions among minority populations and among communities within the same racial/ethnic population. In 2009, the median percentage of men who reported fair or poor health was 15.8% (range: 8.3%-29.3%) among A/PI communities and 26.3% (range: 22.3%-30.8%) among AI communities. The median percentage of women who reported fair or poor health was 20.1% (range: 13.3%-37.2%) among A/PI communities, whereas it was 31.3% (range: 19.4%-44.2%) among Hispanic communities. AI and black communities had a high prevalence of self-reported hypertension, cardiovascular disease, and diabetes. For most communities, prevalence was much higher than that in the corresponding MMSA, county, or state in which the community was located. The median percentages of persons who knew the signs and symptoms of a heart attack and stroke were consistently lower in all four minority communities than the national median. Variations were identified among racial/ethnic populations in the use of preventive services. Hispanics had the lowest percentages of persons who had their cholesterol checked, of those with high blood pressure who were taking antihypertensive medication, and of those with diabetes who had a glycosylated hemoglobin (HbA1C) test in the past year. AIs had the lowest mammography screening rate within 2 years among women aged ≥40 years (median: 72.7%; range: 69.4%-76.2%). A/PIs had the lowest Pap smear screening rate within 3 years (median: 74.4%; range: 60.3%-80.8%). The median influenza vaccination rates in adults aged ≥65 years were much lower among black (57.3%) and Hispanic communities (63.3%) than the national median (70.1%) among the 50 states and DC. Pneumococcal vaccination rates also were lower in black (60.5%), Hispanic (58.5%), and A/PI (59.7%) communities than the national median (68.5%). INTERPRETATIONS: Data from the REACH U.S. Risk Factor Survey demonstrate that residents in most of the minority communities continue to have lower socioeconomic status, greater barriers to health-care access, and greater risks for and burden of disease compared with the general populations living in the same MMSA, county, or state. Substantial variations in prevalence of risk factors, chronic conditions, and use of preventive services among different minority populations and different communities within the same racial/ethnic population provide opportunities for public health intervention. These variations also indicate that different priorities are needed to eliminate health disparities for different communities. PUBLIC HEALTH ACTION: These community-level survey data are being used by CDC and community coalitions to implement, monitor, and evaluate intervention programs in each community. Continuous surveillance of health status in minority communities is necessary so that community-specific, culturally sensitive strategies that include system, environmental, and individual-level changes can be tailored to these communities

    Pausing controls branching between productive and non-productive pathways during initial transcription in bacteria

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    Transcription in bacteria is controlled by multiple molecular mechanisms that precisely regulate gene expression. It has been recently shown that initial RNA synthesis by the bacterial RNA polymerase (RNAP) is interrupted by pauses; however, the pausing determinants and the relationship of pausing with productive and abortive RNA synthesis remain poorly understood. Using single-molecule FRET and biochemical analysis, here we show that the pause encountered by RNAP after the synthesis of a 6-nt RNA (ITC6) renders the promoter escape strongly dependent on the NTP concentration. Mechanistically, the paused ITC6 acts as a checkpoint that directs RNAP to one of three competing pathways: productive transcription, abortive RNA release, or a new unscrunching/scrunching pathway. The cyclic unscrunching/scrunching of the promoter generates a long-lived, RNA-bound paused state; the abortive RNA release and DNA unscrunching are thus not as tightly linked as previously thought. Finally, our new model couples the pausing with the abortive and productive outcomes of initial transcription

    Interfering with nucleotide excision by the coronavirus 3′-to-5′ exoribonuclease

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    Some of the most efficacious antiviral therapeutics are ribonucleos(t)ide analogs. The presence of a 3′-to-5′ proofreading exoribonuclease (ExoN) in coronaviruses diminishes the potency of many ribonucleotide analogs. The ability to interfere with ExoN activity will create new possibilities for control of SARS-CoV-2 infection. ExoN is formed by a 1:1 complex of nsp14 and nsp10 proteins. We have purified and characterized ExoN using a robust, quantitative system that reveals determinants of specificity and efficiency of hydrolysis. Double-stranded RNA is preferred over single-stranded RNA. Nucleotide excision is distributive, with only one or two nucleotides hydrolyzed in a single binding event. The composition of the terminal basepair modulates excision. A stalled SARS-CoV-2 replicase in complex with either correctly or incorrectly terminated products prevents excision, suggesting that a mispaired end is insufficient to displace the replicase. Finally, we have discovered several modifications to the 3′-RNA terminus that interfere with or block ExoN-catalyzed excision. While a 3′-OH facilitates hydrolysis of a nucleotide with a normal ribose configuration, this substituent is not required for a nucleotide with a planar ribose configuration such as that present in the antiviral nucleotide produced by viperin. Design of ExoN-resistant, antiviral ribonucleotides should be feasible
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