Analysis of genetic and environmental sources of variation in serum cholesterol in Tecumseh, Michigan. I. Analysis of the frequency distribution for evidence of a genetic polymorphism.

Analyses of serum cholesterol measurements on 4,619 males and 4,730 females residing in the community of Tecumseh, Michigan, were conducted to estimate the contribution of sex, age, temporal variation, and bimodality to determining the normal variation among individuals sampled without regard to their health status. Female values had a higher mean (2.8 mg/100 ml greater) but smaller variance than males when adjusted by polynomial regression to a common age. Positive skew in the frequency distribution for both sexes was removed by natural logarithm (ln) transformation. Age variation accounted for 28.5% and 29.4% of the variance in a ln cholesterol measurement of males and females, respectively. Between 7% and 10% of the variance in a ln cholesterol value was estimated to be attributable to differences between age-adjusted replicate measurements of the same individual. The reduction in individual variability by adjustment for these contributions to variance will allow a more precise evaluation of the relative contribution of alternate genetic hypotheses as explanations for normal variation in cholesterol. Assuming bimodality, approximately one in 1,000 males and one in 1,000 females belong to a second mode of hypercholesterolemic individuals. The locus determining familial hypercholesterolemia is not a major source of normal phenotypic variation in the Tecumseh population.     

The technique of detecting systolic and diastolic pressure from the transducer output of a PC-based blood pressure monitoring system

A pressure to voltage transducer is used along with a cuff, in a PC-based blood pressure and pulse rate monitoring system for human body. During the blood pressure measurement cycle, the output voltage of the pressure to voltage transducer is recorded digitally using a data acquisition system. The recorded data are then analyzed using software routines to determine the blood pressure and pulse rate of the person under test. However, it is difficult to identify the points of systole and diastole correctly from the recorded data. This paper presents the technique that may be used to determine the systolic and diastolic pressure from the collected data.     

The effect of pressure on the glass transition of biopolymer/co-solute. Part I: The example of gelatin

High-solid materials of gelatin in the presence of co-solute were prepared and subjected to a series of hydrostatic pressures up to 700 MPa. Following this, a study was made of the relaxation properties of the mixture around the glass transition region and the melting behaviour of the gelatin network. Structural properties were monitored using differential scanning calorimetry and small-deformation dynamic oscillation on shear. Thermograms were obtained and master curves of viscoelasticity were constructed for each experimental pressure. The dependence of the empirical shift distances obtained from mechanical measurements and supplementing evidence from thermal analysis argue that the application of pressure did not alter the vitrification or melting characteristics of the gelatin/co-solute system within the experimentally accessible pressure range. Unlike the principle of the time–temperature–pressure superposition applicable to synthetic macromolecules, it may not be possible to incorporate a pressure component into the framework of thermorheological simplicity governing the glass transition of the high-sugar gelatin network.     

Intragenic telSMN mutations: frequency, distribution, evidence of a founder effect, and modification of the spinal muscular atrophy phenotype by cenSMN copy number.

The autosomal recessive neuromuscular disorder proximal spinal muscular atrophy (SMA) is caused by the loss or mutation of the survival motor neuron (SMN) gene, which exists in two nearly identical copies, telomeric SMN (telSMN) and centromeric SMN (cenSMN). Exon 7 of the telSMN gene is homozygously absent in approximately 95% of SMA patients, whereas loss of cenSMN does not cause SMA. We searched for other telSMN mutations among 23 SMA compound heterozygotes, using heteroduplex analysis. We identified telSMN mutations in 11 of these unrelated SMA-like individuals who carry a single copy of telSMN: these include two frameshift mutations (800ins11 and 542delGT) and three missense mutations (A2G, S262I, and T274I). The telSMN mutations identified to date cluster at the 3' end, in a region containing sites for SMN oligomerization and binding of Sm proteins. Interestingly, the novel A2G missense mutation occurs outside this conserved carboxy-terminal domain, closely upstream of an SIP1 (SMN-interacting protein 1) binding site. In three patients, the A2G mutation was found to be on the same allele as a rare polymorphism in the 5' UTR, providing evidence for a founder chromosome; Ag1-CA marker data also support evidence of an ancestral origin for the 800ins11 and 542delGT mutations. We note that telSMN missense mutations are associated with milder disease in our patients and that the severe type I SMA phenotype caused by frameshift mutations can be ameliorated by an increase in cenSMN gene copy number.     

The effect of Sambucol, a black elderberry-based, natural product, on the production of human cytokines: I. Inflammatory cytokines

Sambucus nigra L. products - Sambucol - are based on a standardized black elderberry extract. They are natural remedies with antiviral properties, especially against different strains of influenza virus. Sambucol was shown to be effective in vitro against 10 strains of influenza virus. In a double-blind, placebo-controlled, randomized study, Sambucol reduced the duration of flu symptoms to 3-4 days. Convalescent phase serum showed a higher antibody level to influenza virus in the Sambucol group, than in the control group. The present study aimed to assess the effect of Sambucol products on the healthy immune system - namely, its effect on cytokine production. The production of inflammatory cytokines was tested using blood - derived monocytes from 12 healthy human donors. Adherent monocytes were separated from PBL and incubated with different Sambucol preparations i.e., Sambucol Elderberry Extract, Sambucol Black Elderberry Syrup, Sambucol Immune System and Sambucol for Kids. Production of inflammatory cytokines (IL-1 beta, TNF-alpha, IL-6, IL-8) was significantly increased, mostly by the Sambucol Black Elderberry Extract (2-45 fold), as compared to LPS, a known monocyte activator (3.6-10.7 fold). The most striking increase was noted in TNF-alpha production (44.9 fold). We conclude from this study that, in addition to its antiviral properties, Sambucol Elderberry Extract and its formulations activate the healthy immune system by increasing inflammatory cytokine production. Sambucol might therefore be beneficial to the immune system activation and in the inflammatory process in healthy individuals or in patients with various diseases. Sambucol could also have an immunoprotective or immunostimulatory effect when administered to cancer or AIDS patients, in conjunction with chemotherapeutic or other treatments. In view of the increasing popularity of botanical supplements, such studies and investigations in vitro, in vivo and in clinical trials need to be developed.     

The effect of harp music on heart rate, mean blood pressure, respiratory rate, and body temperature in the African green monkey

BACKGROUND: The effectiveness of recorded harp music as a tool for relaxation for non-human primates is explored in this study. METHODS: Konigsberg Instruments Model T27F-1B cardiovascular telemetry devices were implanted into nine African green monkeys (Chlorocebus aethiops). After post-surgical recovery, animals were exposed to recorded harp music. Telemetry data were collected on heart rate, mean blood pressure, respiratory rate, and body temperature for a 30-minute baseline period before music exposure; a 90-minute period of music exposure; and a 90-minute post-exposure period, where no music was played. RESULTS: No statistical differences were noted in heart rate, mean blood pressure, respiratory rate, and body temperature between pre-exposure, exposure, and post-exposure periods. CONCLUSIONS: The lack of response in these African green monkeys may be attributable to their generally calm demeanor in captivity; experiments with a more excitable species such as the rhesus macaque might demonstrate a significant relaxation response to music.     

The effect of a cortisol analogue and transport stress on the frequency of occurrence of micronuclei in erythrocytes of the peripheral blood of sterlet Acipenser ruthenus L.

The effect of a cortisol analogue and transportation on the occurrence of micronucleus in erythrocytes of the peripheral blood of sterlet was studied. Both factors increased the number of fish with micronucleus and the percentage of aberrant erythrocytes.     

Comparative effects on blood pressure and heart rate of dynorphin A(1–13) in anterior hypothalamic area, posterior hypothalamic area, nucleus tractus solitarius, and lateral cerebral ventricle in the rat

The objective of this study was to explore the effects of the endogenous opioid peptide dynorphin A(1–13) on the CNS regulation of blood pressure and heart rate. Wistar rats, anesthetized with pentobarbital and halothane, received dynorphin A(1–13) microinjected into the anterior hypothalamus area (AHA), the posterior hypothalamic area (PHA), the nucleus tractus solitarius (NTS), or the lateral cerebral ventricle (ICV). Dynorphin A(1–13), 20 (12 nmol) or 30 μg ICV, produced significant (p < 0.05) reductions in blood pressure and heart rate. Naloxone, 50 μg/kg ICV, completely prevented the blood pressure response and significantly (p < 0.05) blunted the heart rate response to the highest dynorphin concentration, 30 μg ICV (18 nmol). Dynorphin A(1–13), 5 μg, in the NTS significantly (p < 0.05) decreased systolic and diastolic blood pressure and heart rate with the response being evident 10 min and persisting for 30 min after injection. In contrast, the same dose of dynorphin A(1–13) in the AHA produced an immediate, marked, and significant (p < 0.05) decrease in systolic and diastolic blood pressure and heart rate that attained its maximum 1–3 min and returned rapidly towards baseline levels. Dynorphin A(1–13), 5 or 10 μg in the posterior hypothalamic area, was not associated with any change in blood pressure or heart rate. Injection of the diluent at any site was not associated with any changes in blood pressure or heart rate. The maximum change in blood pressure with dynorphin was greater in the AHA than NTS, and the maximum change in heart rate was greater in the NTS than AHA. These data indicate a potential role for dynorphin as a modulator of the CNS regulation of blood pressure and cardiac rate, and this is mediated in part through different areas in the brain that maybe localized to the anterior hypothalamic area and nucleus tractus solitarius but not the posterior hypothalamic area.     

The effect of insecticides on the distribution of foracing parasitoids,Diaeretiella rapae [Hym.: Braconidae] on plants

Foraging aphid parasitoids,Diaeretiella rapae M'Intosh, were exposed to sublethal doses of the insecticides pirimicarb, permethrin and malathion on brusslls sprouts plants. Observations on wasp distribution over time revealed that wasps spent less time on sprayed plants, relative to controls and, while on these plants, tended to concentrate activity on unsprayed surfaces. For permethrin and malathion, pesticide residues reversed the stereotypic upward foraging pattern of the wasp. Negative consequences of sublethal pesticide doses for parasitoid foraging efficiency are discussed.      

The effect of aluminium on the distribution of calcium,magnesium and phosphorus in mycorrhizal and non-mycorrhizal seedlings of Eucalyptus rudis: a cryo-microanalytical study

The distribution of Al, Ca, Mg and P in the lateral roots and leaves of mycorrhizal and non-mycorrhizal seedlings of Eucalyptus rudis grown with and without Al was analysed using energy-dispersive X-ray microanalysis on a cryo-scanning electron microscope. Al accumulated in all tissues of nonmycorrhizal plants: the endodermis was not a barrier to the translocation of Al. In mycorrhizal roots, Al was concentrated within the sheath. The presence of Al reduced the levels of Ca and Mg in both mycorrhizal and non-mycorrhizal roots and shoots in comparison with control plants. The presence of mycorrhizas increased the levels of Ca and Mg in plants grown with Al in comparison with non-inoculated plants, although there was no evidence that mycorrhizas increased the levels of P in plants grown in Al-amended soils. P levels were higher in the mycorrhizal sheath of plants grown with Al than the controls.     

The effect of deforestation on the genetic diversity and structure in <Emphasis Type="Italic">Acer saccharum</Emphasis> (Marsh): Evidence for the loss and restructuring of genetic variation in a natural system

The level and distribution of genetic diversity can be influenced by species life history traits and demographic factors, including perturbations that might produce population bottlenecks. Deforestation and forest fragmentation are common sources of population disturbance in contemporary populations of forest ecosystems. Although the genetic effects of forest fragmentation and deforestation have been examined by assessing levels of genetic variation in forest fragments that remain after logging, few considerations have been made of the populations that re-colonize once-cleared areas. Here we examine the effects of human-mediated population bottlenecks on the level and distribution of genetic diversity in natural populations of the long-lived forest tree species, Acer saccharum (sugar maple). We compared genetic variation and structure for populations of sugar maple found within old-growth forested area and in area that has re-colonized since logging. In this study the percent polymorphic loci and allelic richness estimates were reduced in the logged populations compared to old-growth populations. Jackknifed estimates of population genetic differentiation showed significantly higher differentiation among logged populations, with this result being consistently seen when individuals within populations were grouped according to diameter at breast height. The result of decreased genetic variation and higher levels of genetic structure among logged populations suggests that even one extensive bout of logging can alter the level and distribution of genetic variation in this forest tree species.     

Resource distribution and its effect on the mating system of a longhorned beetle,Perarthrus linsleyi (Coleoptera: Cerambycidae)

Summary Adults of Perarthrus linsleyi feed on flowers of creosote bush, Larrea tridentata. Mating also occurs on the flowers and foliage of this plant. This food resource is widely and evenly distributed in space, and is usually abundant. The spatial distribution of the beetles bore no relationship to the spatial distribution of flowers among creosote bushes, nor were female beetles distributed predictably with respect to flower distribution. Males moved widely over the area under study, and moved much more frequently than females. Males actively searched for females, and mounted and began copulation attempts without preliminary courtship. Males did not engage in aggressive defense of females, creosote flowers, or creosote bushes. This species exhibits a scramble competition mating system. The spatial distribution of the food resource is a primary factor in the evolution of the mating system of Perarthrus linsleyi.     

The effect of prey morphology on the feeding behaviour and population growth of the predatory rotifer Asplanchna sieboldi: a case study using five species of Brachionus (Rotifera)

1. We investigated the numerical response, functional response and prey preference of Asplanchna sieboldi to five different prey brachionids. We also analysed the feeding behaviour of the predator in terms of encounters, attacks, capture and prey ingested per unit time. 2. The five prey species (Brachionus havanaensis, B. rubens, B. patulus, B. macracanthus and B. calyciflorus) differed in their body size and spine length. 3. The population growth rates of A. sieboldi ranged from 0.074 ± 0.03 to 0.431 ± 0.02 depending on prey type and density. There was a significant impact of the spine length rather than body size per se on the population growth rates of the predator. 4. The maximum number of prey consumed depended on both body size and spine length. In the functional response analyses, the plateau was reached at a prey density of 4–8 ind. mL^?1. 5. There was a significant impact of prey density on the prey preference of the predator.     

Present,past and future of the European rock fern Asplenium fontanum: combining distribution modelling and population genetics to study the effect of climate change on geographic range and genetic diversity

Background and Aims

Climate change is expected to alter the geographic range of many plant species dramatically. Predicting this response will be critical to managing the conservation of plant resources and the effects of invasive species. The aim of this study was to predict the response of temperate homosporous ferns to climate change.

Methods

Genetic diversity and changes in distribution range were inferred for the diploid rock fern Asplenium fontanum along a South–North transect, extending from its putative last glacial maximum (LGM) refugia in southern France towards southern Germany and eastern-central France. This study reconciles observations from distribution models and phylogeographic analyses derived from plastid and nuclear diversity.

Key Results

Genetic diversity distribution and niche modelling propose that genetic diversity accumulates in the LGM climate refugium in southern France with the formation of a diversity gradient reflecting a slow, post-LGM range expansion towards the current distribution range. Evidence supports the fern''s preference for outcrossing, contradicting the expectation that homosporous ferns would populate new sites by single-spore colonization. Prediction of climate and distribution range change suggests that a dramatic loss of range and genetic diversity in this fern is possible. The observed migration is best described by the phalanx expansion model.

Conclusions

The results suggest that homosporous ferns reproducing preferentially by outcrossing accumulate genetic diversity primarily in LGM climate refugia and may be threatened if these areas disappear due to global climate change.