Associations between Variation in CHRNA5-CHRNA3-CHRNB4, Body Mass Index and Blood Pressure in the Northern Finland Birth Cohort 1966

Background

The CHRNA5-CHRNA3-CHRNB4 gene cluster on 15q25 has consistently been associated with smoking quantity, nicotine dependence and lung cancer. Recent research also points towards its involvement in cardiovascular homeostasis, but studies in large human samples are lacking, especially on the role of the gene cluster in blood pressure regulation.

Methodology/Principal Findings

We studied the associations between 18 single nucleotide polymorphisms (SNPs) in CHRNA5-CHRNA3-CHRNB4 and systolic blood pressure (SBP), diastolic blood pressure (DBP), and body mass index (BMI) in 5402 young adults from the Northern Finland Birth Cohort 1966. We observed some evidence for associations between two SNPs and SBP and between six SNPs and BMI; the evidence for associations with DBP was weaker. The associations with the three phenotypes were driven by different loci with low linkage disequilibrium with each other. The associations appeared more pronounced in smokers, such that the smoking-increasing alleles would predict lower SBP and BMI. Each additional copy of the rs1948 G-allele and the rs950776 A-allele reduced SBP on average by −1.21 (95% CI −2.01, −0.40) mmHg in smokers. The variants associated with BMI included rs2036534, rs6495309, rs1996371, rs6495314, rs4887077 and rs11638372 and had an average effect size of −0.38 (−0.68, −0.08) kg/m² per an additional copy of the risk allele in smokers. Formal assessments of interactions provided weaker support for these findings, especially after adjustment for multiple testing.

Conclusions

Variation at 15q25 appears to interact with smoking status in influencing SBP and BMI. The genetic loci associated with SBP were in low linkage disequilibrium with those associated with BMI suggesting that the gene cluster might regulate SBP through biological mechanisms that partly differ from those regulating BMI. Further studies in larger samples are needed for more precise evaluation of the possible interactions, and to understand the mechanisms behind.     

Foliage phenols and nitrogen in relation to growth,insect damage,and ability to recover after defoliation,in the mountain birch Betula pubescens ssp tortuosa

We studied growth of the mountain birch, and the role of foliage phenols, nitrogen, and variance in the timing of bud burst, as potential defensive characters, in Finnish Lapland in 1975–1979. Annual and local variation both in phenol and nitrogen concentration of foliage were significant. Individual trees retained their position in the foliage and nitrogen distribution of the population in successive years, as well as in the order of leaf flush in spring. Growth of twigs, mature leaf size, and ability of trees to recover in the year following artificial defoliation correlated positively with the sum of degree days in the previous growing season. Foliage nitrogen correlated negatively with foliage phenols in within-site comparisons. Twig growth correlated negatively with foliage phenols, particularly in growing seasons following cool summers, but did not correlate with foliage nitrogen. Birches flushing early did not grow more than birches flushing late. Between-site differences in foliage phenol content were mainly determined by abiotic conditions, like temperature and nutrient availability. In a between-site comparison insect chewing marks in leaves correlated positively with foliage phenols as well as with nitrogen; intensity of invertebrate predation presumably explained variable herbivory between the sites. In a within-site comparison trees with the highest foliage phenol content had few herbivores only at the site with the highest average phenol level.     

Acid secretion of parietal cells is paralleled by a redistribution of NSF and α, β-SNAPs and inhibited by tetanus toxin

Stimulation of parietal cells causes fusion of intracellular tubulovesicles with the canalicular plasma membrane thereby increasing the apical membrane area up to tenfold. The presence of the SNARE proteins synaptobrevin, syntaxin1, and SNAP25 in parietal cells and their intracellular redistribution after stimulation suggest a SNARE-mediated mechanism. Here we show that NSF and alpha, beta-SNAPs which are involved in the dissociation of the SNARE complex in neurons also occur in parietal cells exhibiting subcellular distributions similar to the ones obtained for SNARE proteins and for the H+, K(+)-ATPase. More importantly proteolytic cleavage of synaptobrevin by tetanus neurotoxin completely inhibits the cAMP-dependent increase of acid secretion further supporting the crucial role SNARE proteins play in parietal cells.     

Occurrence of Trichothecenes in feed and cereals in Finland

In 1985 82 samples of feed and food grain were analyzed for trichothecenes deoxynivalenol (DON), nivalenol (NV), diacetoxyscirpenol (DAS), T-2 toxin, HT-2 toxin and fusarenon-X (F-X). Trichothecenes were found in 77 of these samples. The highest amounts were DON 6300 ug/kg and DAS 1680 ug/kg.In 1986, in a corresponding study of 113 samples, trichothecenes were found in 110 samples. A new trichothecene in Finland, 3-acetyldeoxynivalenol (3-AcDON), was identified in 35 of these samples in concentration of 2–211 ug/kg.Analyzing methods were gas chromatography and GC-mass spectrometry. It is characteristic of the feed samples suspected of causing outbreaks in animals in Finland that several trichothecenes are often found in the same sample. As an example of this is a poultry feed with following results: DON 33 ug/kg, 3-AcDON 21 ug/kg, DAS 45 ug/kg, T-2 toxin 40 ug/kg, HT-2 toxin 12 ug/kg.     

Relationships among Body Condition,Insulin Resistance and Subcutaneous Adipose Tissue Gene Expression during the Grazing Season in Mares

Obesity and insulin resistance have been shown to be risk factors for laminitis in horses. The objective of the study was to determine the effect of changes in body condition during the grazing season on insulin resistance and the expression of genes associated with obesity and insulin resistance in subcutaneous adipose tissue (SAT). Sixteen Finnhorse mares were grazing either on cultivated high-yielding pasture (CG) or semi-natural grassland (NG) from the end of May to the beginning of September. Body measurements, intravenous glucose tolerance test (IVGTT), and neck and tailhead SAT gene expressions were measured in May and September. At the end of grazing, CG had higher median body condition score (7 vs. 5.4, interquartile range 0.25 vs. 0.43; P=0.05) and body weight (618 kg vs. 572 kg ± 10.21 (mean ± SEM); P=0.02), and larger waist circumference (P=0.03) than NG. Neck fat thickness was not different between treatments. However, tailhead fat thickness was smaller in CG compared to NG in May (P=0.04), but this difference disappeared in September. Greater basal and peak insulin concentrations, and faster glucose clearance rate (P=0.03) during IVGTT were observed in CG compared to NG in September. A greater decrease in plasma non-esterified fatty acids during IVGTT (P<0.05) was noticed in CG compared to NG after grazing. There was down-regulation of insulin receptor, retinol binding protein 4, leptin, and monocyte chemoattractant protein-1, and up-regulation of adiponectin (ADIPOQ), adiponectin receptor 1 and stearoyl-CoA desaturase (SCD) gene expressions in SAT of both groups during the grazing season (P<0.05). Positive correlations were observed between ADIPOQ and its receptors and between SCD and ADIPOQ in SAT (P<0.01). In conclusion, grazing on CG had a moderate effect on responses during IVGTT, but did not trigger insulin resistance. Significant temporal differences in gene expression profiles were observed during the grazing season.     

HETEROCAPSA ARCTICA SUBSP. FRIGIDA SUBSP. NOV. (PERIDINIALES,DINOPHYCEAE)—DESCRIPTION OF A NEW DINOFLAGELLATE AND ITS OCCURRENCE IN THE BALTIC SEA1

Characteristics important in identification of Heterocapsa species (i.e., thecal plate pattern, body scale structure, and shape and position of the nucleus and pyrenoid) are practically identical in the dinoflagellate investigated here and in Heterocapsa arctica T. Horig. described from the Canadian Arctic. Analysis of internal transcribed spacer (ITS) sequences confirms that the two dinoflagellates are very closely related; however, there is a clear difference in their size and shape. Our experiments show that the low‐salinity Baltic Sea brackish water does not reduce the size of the marine H. arctica to match that of the Baltic Sea morphotype. On the basis of these dissimilarities in general morphology and its geographic isolation in the Baltic Sea, we consider our material sufficiently differentiated from the typical H. arctica to warrant the status of a new subspecies, H. arctica subsp. frigida subsp. nov. Being of a distinct cell shape, the occurrence of subsp. frigida has been recorded in Algaline phytoplankton monitoring data collected since 1993. Although it has never been responsible for high biomass blooms, it commonly occurs in spring in the Northern Baltic Proper and in the western Gulf of Finland, when the water temperatures are <5°C.     

Effects of low-intensity training on dihydropyridine and ryanodine receptor content in skeletal muscle of mouse

To evaluate low-intensity exercise training induced changes in the expression of dihydropyridine (DHP) and ryanodine (Ry) receptors both mRNA and protein levels were determined by quantitative RT-PCR and immunoblot analysis from gastrocnemius (GAS) and rectus femoris (RF) muscles of mice subjected to a 15-week aerobic exercise program. The level of muscular work was assayed by changes in myosin heavy chain (MHC) content, myoglobin (Mb) expression and muscle size. The mRNA expression and optical density of DHP receptor increased significantly in GAS by 66.8 and 39.5%, respectively. The expression of Ry receptor, on the other hand, was not up-regulated. In RF, there was a significant increase of 38.4% in the mRNA expression of DHP receptor, although the protein level remained the same. No changes in Ry receptor expression was observed. The training resulted in a 1.58% increase in the amount of MHC IIa and a 2.34% decrease in that of IIb and IId in GAS. A significant 8.3% increase in the Mb content was observed. In RF, no significant changes in MHC or in Mb content were noted. Our results show that an evident increase in the mRNA and protein expression of DHP receptor was induced in GAS even by a relatively low-intensity exercise. Surprisingly, contrast to DHP receptor expression, no changes in Ry receptor mRNA, or protein levels were found, indicating more abundant demand for DHP receptor after increased muscle activity.     

Resistance of Scots pine wood to Brown-rot fungi after long-term forest fertilization

The susceptibility of Scots pine (Pinus sylvestris L.) sap- and heartwood against the wood decaying brown-rot fungus (Coniophora puteana) was investigated after long-term forest fertilization at three different sites in central Finland. Different wood properties: wood extractives, wood chemistry, and wood anatomy were used to explain sap- and heartwood decay. Scots pine sapwood was more susceptible to decay than its heartwood. In one site, sapwood seemed to be more resistant to wood decay after forest fertilization whereas the susceptibility of heartwood increased. Significant changes in the sapwood chemistry were found between treatment and sites, however, no relationship between wood chemistry and wood decay was observed in the factor analysis. The results of this study show that there was an inconsistent relationship between decay susceptibility and fertilization and the measured physical and chemical attributes of the wood were not consistently correlated with the decay rate.