249 research outputs found
The brain and inner ear of the early Paleocene ‘condylarth’ Carsioptychus coarctatus: implications for early placental mammal neurosensory biology and behavior
Analysis of multiple single nucleotide polymorphisms closely positioned in the ovine PRNP gene using linear fluorescent probes and melting curve analysis
<p>Abstract</p> <p>Background</p> <p>Resistance and susceptibility to scrapie has been associated with single nucleotide polymorphisms located within codons 136, 154 and 171 of the ovine prion protein gene (<it>PRNP</it>). Dual-labelled HyBeacon probes were developed to analyse single and clustered polymorphisms within these and neighbouring codons.</p> <p>Methods</p> <p>Extracted DNAs and unpurified blood samples were genotyped with respect to polymorphisms in <it>PRNP </it>codons 136, 141, 154 and 171. PCR amplicons were investigated using a LightTyper instrument, measuring the stability of probe/target hybridisation through peak melting temperatures and determining the sequence of nucleotides at polymorphic sites.</p> <p>Results</p> <p>The performance of HyBeacon assays was evaluated in a validation study comparing genotypes with those obtained using a primer extension assay (Sequenom MassEXTEND) analysed on a MALDI-ToF mass spectrometer. Over 12,000 sheep samples were successfully genotyped, reliably detecting A<sup>136</sup>, V<sup>136</sup>, T<sup>136</sup>, T<sup>137</sup>, L<sup>141</sup>, F<sup>141 </sup>R<sup>154</sup>, H<sup>154</sup>, L<sup>168</sup>, R<sup>171</sup>, Q<sup>171</sup>, H<sup>171 </sup>and K<sup>171 </sup>sequence variants using only 4 HyBeacon probes.</p> <p>Conclusion</p> <p>HyBeacon assays provide an extremely robust and accurate method for the analysis of single and clustered <it>PRNP </it>polymorphisms in a high-throughput format. The flexibility of the diagnostic tests ensures that samples are correctly genotyped even in the presence of additional sequence variations that flank the polymorphisms of interest. Such sequence variations may also be neutralised using universal bases such as 5-nitroindole if required.</p
Prosopis tamarugo Phil.: a native tree from the Atacama Desert groundwater table depth thresholds for conservation
The F-actin cytoskeleton in syncytia from non-clonal progenitor cells
The actin cytoskeleton of plant syncytia (a multinucleate cell arising through fusion) is poorly known: to date, there have only been reports about F-actin organization in plant syncytia induced by parasitic nematodes. To broaden knowledge regarding this issue, we analyzed F-actin organization in special heterokaryotic Utricularia syncytia, which arise from maternal sporophytic tissues and endosperm haustoria. In contrast to plant syncytia induced by parasitic nematodes, the syncytia of Utricularia have an extensive F-actin network. Abundant F-actin cytoskeleton occurs both in the region where cell walls are digested and the protoplast of nutritive tissue cells fuse with the syncytium and also near a giant amoeboid in the shape nuclei in the central part of the syncytium. An explanation for the presence of an extensive F-actin network and especially F-actin bundles in the syncytia is probably that it is involved in the movement of nuclei and other organelles and also the transport of nutrients in these physiological activity organs which are necessary for the development of embryos in these unique carnivorous plants. We observed that in Utricularia nutritive tissue cells, actin forms a randomly arranged network of F-actin, and later in syncytium, two patterns of F-actin were observed, one characteristic for nutritive cells and second—actin bundles—characteristic for haustoria and suspensors, thus syncytia inherit their F-actin patterns from their progenitors
Factors that affect quality of life among people living with HIV attending an urban clinic in Uganda: A cohort study
© 2015 Mutabazi-Mwesigire et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction: With the availability of antiretroviral therapy (ART) and primary general care for people living with HIV (PLHIV) in resource limited settings, PLHIV are living longer, and HIV has been transformed into a chronic illness. People are diagnosed and started on treatment when they are relatively well. Although ART results in clinical improvement, the ultimate goal of treatment is full physical functioning and general well-being, with a focus on quality of life rather than clinical outcomes. However, there has been little research on the relationship of specific factors to quality of life in PLHIV. The objective of this study was to investigate factors associated with quality of life among PLHIV in Uganda receiving basic care and those on ART. Methods: We enrolled 1274 patients attending an HIV outpatient clinic into a prospective cohort study. Of these, 640 received ART. All were followed up at 3 and 6 months. Health related quality of life was assessed with the MOS-HIV Health Survey and the Global Person Generated Index (GPGI). Multivariate linear regression and logistic regression with generalized estimating equations were used to examine the relationship of social behavioral and disease factors with Physical Health Summary (PHS) score, Mental Health Summary (MHS) score, and GPGI. Results: Among PLHIV receiving basic care, PHS was associated with: sex (p=0.045) - females had lower PHS; age in years at enrollment (p=0.0001) - older patients had lower PHS; and depression (
Magnitude, precision, and realism of depth perception in stereoscopic vision
Our perception of depth is substantially enhanced by the fact that we have binocular vision. This provides us with more precise and accurate estimates of depth and an improved qualitative appreciation of the three-dimensional (3D) shapes and positions of objects. We assessed the link between these quantitative and qualitative aspects of 3D vision. Specifically, we wished to determine whether the realism of apparent depth from binocular cues is associated with the magnitude or precision of perceived depth and the degree of binocular fusion. We presented participants with stereograms containing randomly positioned circles and measured how the magnitude, realism, and precision of depth perception varied with the size of the disparities presented. We found that as the size of the disparity increased, the magnitude of perceived depth increased, while the precision with which observers could make depth discrimination judgments decreased. Beyond an initial increase, depth realism decreased with increasing disparity magnitude. This decrease occurred well below the disparity limit required to ensure comfortable viewing
The counseling african americans to control hypertension (caatch) trial: baseline demographic, clinical, psychosocial, and behavioral characteristics
<p>Abstract</p> <p>Background</p> <p>Effectiveness of combined physician and patient-level interventions for blood pressure (BP) control in low-income, hypertensive African Americans with multiple co-morbid conditions remains largely untested in community-based primary care practices. Demographic, clinical, psychosocial, and behavioral characteristics of participants in the Counseling African American to Control Hypertension (CAATCH) Trial are described. CAATCH evaluates the effectiveness of a multi-level, multi-component, evidence-based intervention compared with usual care (UC) in improving BP control among poorly controlled hypertensive African Americans who receive primary care in Community Health Centers (CHCs).</p> <p>Methods</p> <p>Participants included 1,039 hypertensive African Americans receiving care in 30 CHCs in the New York Metropolitan area. Baseline data on participant demographic, clinical (<it>e.g</it>., BP, anti-hypertensive medications), psychosocial (<it>e.g</it>., depression, medication adherence, self-efficacy), and behavioral (<it>e.g</it>., exercise, diet) characteristics were gathered through direct observation, chart review, and interview.</p> <p>Results</p> <p>The sample was primarily female (71.6%), middle-aged (mean age = 56.9 ± 12.1 years), high school educated (62.4%), low-income (72.4% reporting less than $20,000/year income), and received Medicaid (35.9%) or Medicare (12.6%). Mean systolic and diastolic BP were 150.7 ± 16.7 mm Hg and 91.0 ± 10.6 mm Hg, respectively. Participants were prescribed an average of 2.5 ± 1.9 antihypertensive medications; 54.8% were on a diuretic; 33.8% were on a beta blocker; 41.9% were on calcium channel blockers; 64.8% were on angiotensin converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs). One-quarter (25.6%) of the sample had resistant hypertension; one-half (55.7%) reported medication non-adherence. Most (79.7%) reported one or more co-morbid medical conditions. The majority of the patients had a Charlson Co-morbidity score ≥ 2. Diabetes mellitus was common (35.8%), and moderate/severe depression was present in 16% of participants. Participants were sedentary (835.3 ± 1,644.2 Kcal burned per week), obese (59.7%), and had poor global physical health, poor eating habits, high health literacy, and good overall mental health.</p> <p>Conclusions</p> <p>A majority of patients in the CAATCH trial exhibited adverse lifestyle behaviors, and had significant medical and psychosocial barriers to adequate BP control. Trial outcomes will shed light on the effectiveness of evidence-based interventions for BP control when implemented in real-world medical settings that serve high numbers of low-income hypertensive African-Americans with multiple co-morbidity and significant barriers to behavior change.</p
Internally coupled ears in living mammals.
It is generally held that the right and left middle ears of mammals are acoustically isolated from each other, such that mammals must rely on neural computation to derive sound localisation cues. There are, however, some unusual species in which the middle ear cavities intercommunicate, in which case each ear might be able to act as a pressure-difference receiver. This could improve sound localisation at lower frequencies. The platypus Ornithorhynchus is apparently unique among mammals in that its tympanic cavities are widely open to the pharynx, a morphology resembling that of some non-mammalian tetrapods. The right and left middle ear cavities of certain talpid and golden moles are connected through air passages within the basicranium; one experimental study on Talpa has shown that the middle ears are indeed acoustically coupled by these means. Having a basisphenoid component to the middle ear cavity walls could be an important prerequisite for the development of this form of interaural communication. Little is known about the hearing abilities of platypus, talpid and golden moles, but their audition may well be limited to relatively low frequencies. If so, these mammals could, in principle, benefit from the sound localisation cues available to them through internally coupled ears. Whether or not they actually do remains to be established experimentally.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00422-015-0675-
Where are you from, stranger? The enigmatic biogeography of North African pond turtles (Emys orbicularis) .
Abstract The European pond turtle (Emys orbicularis) is a
Nearctic element in the African fauna and thought to have
invaded North Africa from the Iberian Peninsula. All North
African populations are currently identified with the subspecies
E. o. occidentalis. However, a nearly range-wide sampling in
North Africa used for analyses of mitochondrial and microsatellite
DNA provides evidence that only Moroccan populations
belong to this taxon, while eastern Algerian and Tunisian pond
turtles represent an undescribed distinct subspecies. These two
taxa are most closely related to E. o. galloitalica with a native
distribution along the Mediterranean coast of northern Spain
through southern France to western and southern Italy. This
group is sister to a clade comprising several mitochondrial lineages
and subspecies of E. orbicularis from Central and Eastern
Europe plus Asia, and the successive sisters are E. o. hellenica
and E. trinacris. Our results suggest that E. orbicularis has been
present in North Africa longer than on the Iberian Peninsula and
that after an initial invasion of North Africa by pond turtles from
an unknown European source region, there was a phase of
diversification in North Africa, followed by a later re-invasion
of Europe by one of the African lineages. The differentiation of
pond turtles in North Africa parallels a general phylogeographic
paradigm in amphibians and reptiles, with deeply divergent
lineages in the western and eastern Maghreb. Acknowledging
their genetic similarity, we propose to synonymize the previously
recognized Iberian subspecies E. o. fritzjuergenobsti with E. o.
occidentalis sensu stricto. The seriously imperiled Moroccan
populations of E. o. occidentalis represent two Management
Units different in mitochondrial haplotypes and microsatellite
markers. The conservation status of eastern Algerian pond turtles
is unclear, while Tunisian populations are endangered.
Considering that Algerian and Tunisian pond turtles represent
an endemic taxon, their situation throughout the historical range
should be surveyed to establish a basis for conservation
measures
Experience of physical violence and mental health among young men and women: a population-based study in Sweden
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