Viral abundance and processes in the water column and sediments are well studied for some systems; however, we know relatively little about virus-host interactions on particles and how particles ...influence these interactions. Here we review virus-prokaryote interactions on inorganic and organic particles in the water column. Profiting from recent methodological progress, we show that confocal laser scanning microscopy in combination with lectin and nucleic acid staining is one of the most powerful methods to visualize the distribution of viruses and their hosts on particles such as organic aggregates. Viral abundance on suspended matter ranges from 10
to 10
ml
. The main factors controlling viral abundance are the quality, size and age of aggregates and the exposure time of viruses to aggregates. Other factors such as water residence time likely act indirectly. Overall, aggregates appear to play a role of viral scavengers or reservoirs rather than viral factories. Adsorption of viruses to organic aggregates or inorganic particles can stimulate growth of the free-living prokaryotic community, e.g. by reducing viral lysis. Such mechanisms can affect microbial diversity, food web structure and biogeochemical cycles. Viral lysis of bacterio- and phytoplankton influences the formation and fate of aggregates and can, for example, result in a higher stability of algal flocs. Thus, viruses also influence carbon export; however, it is still not clear whether they short-circuit or prime the biological pump. Throughout this review, emphasis has been placed on defining general problems and knowledge gaps in virus-particle interactions and on providing avenues for further research, particularly those linked to global change.
Background. This study was designed to determine whether an education program consisting of classroom and on-road training could enhance driving performance. Methods. This randomized controlled trial ...with blinded endpoint assessment enrolled 126 community-living drivers 70 years old or older who were recruited from clinic and community sources. Treatment assignment was concealed until eligibility was established. Participants randomized to intervention underwent two 4-hour classroom and two 1-hour on-road sessions focused on common problem areas of older drivers. Controls received modules directed at vehicle, home, and environmental safety. A knowledge test and driving performance were assessed at baseline and 8 weeks. On-road driving performance was assessed by an experienced evaluator in a dual-brake–equipped vehicle in urban, residential, and highway traffic. Driving performance was rated on a 36-item scale with potential scores from 0 to 72 (higher score better). The knowledge test included 20 road knowledge and eight road sign questions, scored from 0 to 28 correct. Results. The least squares mean change in road test score relative to baseline was 2.87 points higher in the intervention than in the control group (p =.001). The least squares mean change in knowledge test scores relative to baseline was 3.45 points higher in the intervention than in the control group (p <.001). Conclusions. An education program consisting of classroom and on-road training targeted to common errors of older drivers enhanced performance on knowledge and on-road tests. Such interventions offer older drivers the potential to continue driving safely longer and to maintain their out-of-home mobility.
In riverine water, both suspended particulate material and viruses are prominent ecological factors. The existence of various particle types and differences in viral abundance impose variability in ...microenvironments. Particulates and their microbial surrounding may interact in several ways, this interaction being strongly dependent on particle quality and the abundance of organisms involved. In laboratory experiments, we used different suspended matter types (fresh and aged mineral sediment and leaf litter, river snow) that typically occur in riverine environments as model particles. We investigated the effects of particle quality and different ambient viral abundances (×1, ×2 enrichments, and inactivated viruses) on several microbial parameters (changes in bacterial and viral abundances, bacterial production, specific bacterial production) of both the free-living and particle-attached fractions using water from a floodplain system of the Danube River (Austria). Both seston quality and variable viral abundances in the bulk water influenced some microbial parameters. The average abundance of bacteria and viruses was significantly higher on organic than on inorganic particles and on aged particles (for both sediment and leaf litter). Changes in bacterial abundance during the course of the experiments were also influenced by particle quality, with, for example, aged sediment favoring increasing abundances. Virus:bacterium ratios (VBR) were significantly higher on organic than on inorganic particles, but significantly lower on suspended particles than in the plank-tonic fraction. Typically, bacterial secondary production (overall and cell-specific) was higher on particles than in bulk water. Bacterial productivity in the ambient water was negatively affected by the abundance of planktonic viruses but positively affected by that of attached viruses. These findings from experimental systems may foster
studies of particle-rich environments.
IMPORTANCE The effect of serious injuries, such as hip fracture and head injury, on mortality and function is comparable to that of cardiovascular events. Concerns have been raised about the risk of ...fall injuries in older adults taking antihypertensive medications. The low risk of fall injuries reported in clinical trials of healthy older adults may not reflect the risk in older adults with multiple chronic conditions. OBJECTIVE To determine whether antihypertensive medication use was associated with experiencing a serious fall injury in a nationally representative sample of older adults. DESIGN, PARTICIPANTS, AND SETTING Competing risk analysis as performed with propensity score adjustment and matching in the nationally representative Medicare Current Beneficiary Survey cohort during a 3-year follow-up through 2009. Participants included 4961 community-living adults older than 70 years with hypertension. EXPOSURES Antihypertensive medication intensity based on the standardized daily dose for each antihypertensive medication class that participants used. MAIN OUTCOMES AND MEASURES Serious fall injuries, including hip and other major fractures, traumatic brain injuries, and joint dislocations, ascertained through Centers for Medicare & Medicaid Services claims. RESULTS Of the 4961 participants, 14.1% received no antihypertensive medications; 54.6% were in the moderate-intensity and 31.3% in the high-intensity antihypertensive groups. During follow-up, 446 participants (9.0%) experienced serious fall injuries, and 837 (16.9%) died. The adjusted hazard ratios for serious fall injury were 1.40 (95% CI, 1.03-1.90) in the moderate-intensity and 1.28 (95% CI, 0.91-1.80) in the high-intensity antihypertensive groups compared with nonusers. Although the difference in adjusted hazard ratios across the groups did not reach statistical significance, results were similar in the propensity score–matched subcohort. Among 503 participants with a previous fall injury, the adjusted hazard ratios were 2.17 (95% CI, 0.98-4.80) for the moderate-intensity and 2.31 (95% CI, 1.01-5.29) for the high-intensity antihypertensive groups. CONCLUSIONS AND RELEVANCE Antihypertensive medications were associated with an increased risk of serious fall injuries, particularly among those with previous fall injuries. The potential harms vs benefits of antihypertensive medications should be weighed in deciding to continue treatment with antihypertensive medications in older adults with multiple chronic conditions.
Summary
We carried out a systematic overview using individual patient data from the seven randomised trials that have compared a strategy of initial coronary artery bypass graft (CABG) surgery with ...one of initial medical therapy to assess the effects on mortality in patients with stable coronary heart disease (stable angina not severe enough to necessitate surgery on grounds of symptoms alone, or myocardial infarction).
1324 patients were assigned CABG surgery and 1325 medical management between 1972 and 1984. The proportion of patients in the medical treatment group who had undergone CABG surgery was 25% at 5 years, 33% at 7 years, and 41% at 10 years: 93·7% of patients assigned to the surgery group underwent CABG surgery. The CABG group had significantly lower mortality than the medical treatment group at 5 years (10·2 vs 15·8%; odds ratio 0·61 95% Cl 0·48-0·77, p=0·0001), 7 years (15·8 vs 21·7%; 0·68 0·56-0·83, p<0·001), and 10 years (26·4 vs 30·5%; 0·83 0·70-0·98; p=0·03). The risk reduction was greater in patients with left main artery disease than in those with disease in three vessels or one or two vessels (odds ratios at 5 years 0·32, 0·58, and 0·77, respectively). Although relative risk reductions in subgroups defined by other baseline characteristics were similar, the absolute benefits of CABG surgery were most pronounced in patients in the highest risk categories. This effect was most evident when several prognostically important clinical and angiographic risk factors were integrated to stratify patients by risk levels and the extension of survival at 10 years was examined (change in survival - 1·1 SE 3·1 months in low-risk group, 5·0 4·2 months in moderate-risk group, and 8·8 5·4 months in high-risk group; p for trend <0·003).
A strategy of initial CABG surgery is associated with lower mortality than one of medical management with delayed surgery if necessary, especially in high-risk and medium-risk patients with stable coronary heart disease. In low-risk patients, the limited data show a non-significant trend towards greater mortality with CABG.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SBJE, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Although the sophistication and flexibility of the statistical technology available to the data analyst have increased, some durable, simple principles remain valid. Hypothesis‐driven analyses, which ...were anticipated and specified in the protocol, must still be kept separate and privileged relative to the important, but risky data mining made possible by modern computers. Analyses that have a firm basis in the randomization are interpreted more easily than those that rely heavily on statistical models. Outcomes—such as quality of life, symptoms, and behaviors—that require the cooperation of subjects to be measured will come to be more and more important as trials move away from mortality as the main outcome. Inevitably, such trials will have to deal with more missing data, especially because of dropout and noncompliance. There are fundamental limits on the ability of statistical methods to compensate for such problems, so they must be considered when studies are designed. Finally, it must be emphasized that the availability of software is not a substitute for experience and statistical expertise.
The increased interest for categorising countries at risk calls for an improved methodology allowing comparison of natural hazard impacts at a global level. A disaster is the intersection between a ...hazardous event, the elements at risk (population, infrastructures) and their vulnerability. In order to associate reported impacts with affected elements and socio-economic or geophysical contextual parameters, geographical location and extent of hazards is needed. The scope of this paper is to present improved automated procedures for a rapid mapping of large disastrous hazard events (floods, earthquakes, cyclones and volcanoes) using Geographical Information Systems (GIS) and available global datasets. Up to 82% of the events and 88% of the reported victims could be geo-referenced and the results highlight both the potentialities and limitations of the methods applied.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Injuries from falls are major contributors to death and complications in older adults. In this pragmatic, cluster-randomized trial, a multifactorial intervention that was administered by nurses did ...not result in a significantly lower rate of first adjudicated serious fall injury than enhanced usual care.
Background. Chronically ill older adults constitute a population vulnerable for complications associated with influenza. Study of their immunity to influenza virus may help design better strategies ...to stimulate protective immune responses. Methods. Immunogenicity of influenza vaccines and immune protection from natural influenza were assessed in older adults with chronic obstructive pulmonary disease as part of a vaccine efficacy trial. Subjects received either trivalent inactivated influenza virus vaccine (TVV) intramuscularly and trivalent live cold-adapted influenza virus vaccine (CAIV-T; n = 1107) intranasally (inl) or TVV and placebo inl (P; n = 1108). Results. In the subsets of study subjects assessed, serum hemagglutination inhibition (HAI) and nasal-wash antihemagglutinin (HA) immunoglobulin (Ig) A and IgG antibody levels and anti-influenza virus CD8+ cytotoxic T lymphocyte activity increased after immunization. Mean postimmunization nasal-wash IgA antibody levels to influenza A H3/HA and B HA were statistically higher in the TVV + CAIV-T group (n = 957) than in the TVV + P group (n = 951). Postimmunization serum HAI and nasal-wash IgA antibodies to influenza A/H3N2 and B viruses were associated with a reduced relative risk for natural influenza infection. Conclusions. TVV + CAIV-T appeared more immunogenic than TVV + P, but the observed difference may be clinically unimportant. Anti-influenza serum and nasal-wash antibodies were associated with immune protection.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
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