100 research outputs found
The c.1460C>T Polymorphism of MAO-A Is Associated with the Risk of Depression in Postmenopausal Women
Objective. The aim of the study was an evaluation of possible relationships between polymorphisms of serotoninergic system genes and the risk of depression in postmenopausal women. Methods. We studied 332 women admitted to our department because of climacteric symptoms. The study group included 113 women with a diagnosis of depressive disorder according to the Hamilton rating scale for depression; the controls consisted of 219 women without depression. Serum 17β-estradiol concentrations were evaluated using radioimmunoassay, while polymorphisms in serotoninergic system genes: serotonin receptors 2A (HTR2A), 1B (HTR1B), and 2C (HTR2C); tryptophan hydroxylase 1 (TPH1) and 2 (TPH2), and monoamine oxidase A (MAO-A) were evaluated using polymerase chain reaction-restriction. Results. We found that the 1460T allele of MAO-A c.1460C>T (SNP 1137070) appeared with a significantly higher frequency in depressed female patients than in the control group (P = 0.011) and the combined c.1460CT + TT genotypes were associated with a higher risk of depression (P = 0.0198). Patients with the 1460TT genotype had a significantly higher 17β-estradiol concentration than patients with the 1460CT genotype (P = 0.0065) and 1460CC genotype (P = 0.0018). Conclusions. We concluded that depression in postmenopausal women is closely related to the genetic contribution of MAO-A
Assessment of Application Technology of Natural User Interfaces in the Creation of a Virtual Chemical Laboratory
Decreased expression of 17β-hydroxysteroid dehydrogenase type 1 is associated with DNA hypermethylation in colorectal cancer located in the proximal colon
<p>Abstract</p> <p>Background</p> <p>The importance of 17β-estradiol (E2) in the prevention of large bowel tumorigenesis has been shown in many epidemiological studies. Extragonadal E2 may form by the aromatase pathway from androstenedione or the sulfatase pathway from estrone (E1) sulfate followed by E1 reduction to E2 by 17-β-hydroxysteroid dehydrogenase (HSD17B1), so <it>HSD17B1 </it>gene expression may play an important role in the production of E2 in peripheral tissue, including the colon.</p> <p>Methods</p> <p><it>HSD17B1 </it>expression was analyzed in colorectal cancer cell lines (HT29, SW707) and primary colonic adenocarcinoma tissues collected from fifty two patients who underwent radical colon surgical resection. Histopathologically unchanged colonic mucosa located at least 10-20 cm away from the cancerous lesions was obtained from the same patients. Expression level of <it>HSD17B1 </it>using quantitative PCR and western blot were evaluated. DNA methylation level in the 5' flanking region of <it>HSD17B1 </it>CpG rich region was assessed using bisulfite DNA sequencing and HRM analysis. The influence of DNA methylation on HSD17B1 expression was further evaluated by ChIP analysis in HT29 and SW707 cell lines. The conversion of estrone (E1) in to E2 was determined by electrochemiluminescence method.</p> <p>Results</p> <p>We found a significant decrease in HSD17B1 transcript (<it>p </it>= 0.0016) and protein (<it>p </it>= 0.0028) levels in colorectal cancer (CRC) from the proximal but not distal colon and rectum. This reduced <it>HSD17B1 </it>expression was associated with significantly increased DNA methylation (<it>p </it>= 0.003) in the CpG rich region located in the 5' flanking sequence of the <it>HSD17B1 </it>gene in CRC in the proximal but not distal colon and rectum. We also showed that 5-dAzaC induced demethylation of the 5' flanking region of <it>HSD17B1</it>, leading to increased occupation of the promoter by Polymerase II, and increased transcript and protein levels in HT29 and SW707 CRC cells, which contributed to the increase in E2 formation.</p> <p>Conclusions</p> <p>Our results showed that reduced <it>HSD17B1 </it>expression can be associated with DNA methylation in the 5' flanking region of <it>HSD17B1 </it>in CRC from the proximal colon.</p
Impacts of soil conditions and light availability on natural regeneration of Norway spruce Picea abies (L.) H. Karst. in low-elevation mountain forests
& Key message Natural regeneration of P. abies (L.) H. Karst. may reach high densities in lower mountain elevations. The
highest densities were found in sites with moderate light availability, with low pH, and not near the riverbank. However,
age-height classes differed in the predicted magnitude of response, but were consistent in response directions. Mosses and
understory species typical of coniferous forests were positively correlated with regeneration density.
& Context Norway spruce Picea abies (L.) H. Karst. in Central Europe is at risk under climate change scenarios, particularly in
mountain regions. Little is known about the impact of environmental factors on the natural regeneration of P. abies in lowelevation mountain forests.
& Aims We aimed to assess impacts of distance from the riverbank, soil pH, and light availability on natural P. abies regeneration.
We hypothesized that (1) natural P. abiesregeneration would depend on light availability and soil pH and (2) there are understory
plant species which may indicate the microsites suitable for natural regeneration of P. abies.
& Methods The study was conducted in the Stołowe Mountains National Park (SW Poland, 600–800 m a.s.l.). We established 160
study plots (25 m2
) for natural regeneration, light availability, soil pH, and understory vegetation assessment
Integrated global assessment of the natural forest carbon potential
Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system 1. Remote-sensing estimates to quantify carbon losses from global forests 2–5 are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these estimates. Here we combine several ground-sourced 6 and satellite-derived approaches 2,7,8 to evaluate the scale of the global forest carbon potential outside agricultural and urban lands. Despite regional variation, the predictions demonstrated remarkable consistency at a global scale, with only a 12% difference between the ground-sourced and satellite-derived estimates. At present, global forest carbon storage is markedly under the natural potential, with a total deficit of 226 Gt (model range = 151–363 Gt) in areas with low human footprint. Most (61%, 139 Gt C) of this potential is in areas with existing forests, in which ecosystem protection can allow forests to recover to maturity. The remaining 39% (87 Gt C) of potential lies in regions in which forests have been removed or fragmented. Although forests cannot be a substitute for emissions reductions, our results support the idea 2,3,9 that the conservation, restoration and sustainable management of diverse forests offer valuable contributions to meeting global climate and biodiversity targets
The global biogeography of tree leaf form and habit
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17–34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling
The global biogeography of tree leaf form and habit
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling
The global biogeography of tree leaf form and habit.
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling
Native diversity buffers against severity of non-native tree invasions
Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies. Here, leveraging global tree databases, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions
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