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Ecotypic differentiation of Cochlearia officinalis L. was studied in four populations, roughly described as "beach", "bird cliff", "spring" and "estuary", which occupy different habitats in the northern part of Norway. The plants were cultivated under controlled conditions on soil to which nitrogen was applied at various amounts (0, 0.2 and 1.0 g N pot−1). The above ground part of the "bird cliff" population showed the highest dry weight and nitrogen uptake at the highest nitrogen concentration. No effect of nitrogen treatment and the lowest dry weight were found in the "estuary" population. The differences in population response to added nitrogen were correlated to the nitrogen content of the soil in their natural habitat. Morphological features of the populations were also significantly different. The "estuary", "beach" and "bird cliff" populations showed differences in all characteristics measured – ratio of length/width of the leaves, shape of the leaf base, and length of the petiole. "Beach" and "spring" differed significantly in petiole length, while "bird cliff" and "spring" differed significantly in both leaf ratio and shape of the leaf base. These morphological features were not significantly altered by the application of nitrogen to the soil. This study shows that the four populations of Cochlearia officinalis are discrete biotypes characteristic of distinct habitats, and therefore, should be considered ecotypes.  相似文献   
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Depressive symptoms during pregnancy are common and may have impact on the developing child. Selective serotonin reuptake inhibitors (SSRIs) are the most prescribed antidepressant treatment, but unfortunately, these treatments can also negatively affect the behavioral development and health of a child during pregnancy. In addition, serotonin (5-HT) exerts neurotrophic actions with thus far not fully known effects in the offspring. The neurotrophic growth factor (NGF) is involved in neuronal cell survival and differentiation, and altered placenta levels have been found to increase the risk for pregnancy complications, similar to those found in women treated with SSRIs. We therefore investigated whether the NGF signaling pathway was altered in the placenta from women treated with SSRIs (n = 12) and compared them with placenta from depressed (n = 12) and healthy mothers (n = 12). Results from immunohistochemical stainings revealed that placental NGF protein levels of SSRI-treated women were increased in both trophoblasts and endothelial cells compared with depressed and control women. In addition, downstream of the NGF receptor TrkA, increased levels of the signaling proteins ROCK2 and phosphorylated Raf-1 were found in stromal cells and a tendency towards increased levels of ROCK2 in trophoblasts and endothelial cells in SSRI-treated women when compared to healthy controls. SSRI-treated women also displayed increased levels of phosphorylated ROCK2 in all placental cell types studied in comparison with depressed and control women. Interestingly, in placental endothelial cells from depressed women, NGF levels were significantly lower compared to control women, but ROCK2 levels were increased compared with control and SSRI-treated women. Taken together, these results show that the NGF signaling and downstream pathways in the placenta are affected by SSRI treatment and/or antenatal depression. This might lead to an altered placental function, although the clinical relevance of our findings still needs to be investigated.  相似文献   
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In order to understand the effect of global change on marine fishes, it is imperative to quantify the effects on fundamental parameters such as survival and growth. Larval survival and recruitment of the Atlantic cod (Gadus morhua) were found to be heavily impaired by end‐of‐century levels of ocean acidification. Here, we analysed larval growth among 35–36 days old surviving larvae, along with organ development and ossification of the skeleton. We combined CO2 treatments (ambient: 503 µatm, elevated: 1,179 µatm) with food availability in order to evaluate the effect of energy limitation in addition to the ocean acidification stressor. As expected, larval size (as a proxy for growth) and skeletogenesis were positively affected by high food availability. We found significant interactions between acidification and food availability. Larvae fed ad libitum showed little difference in growth and skeletogenesis due to the CO2 treatment. Larvae under energy limitation were significantly larger and had further developed skeletal structures in the elevated CO2 treatment compared to the ambient CO2 treatment. However, the elevated CO2 group revealed impairments in critically important organs, such as the liver, and had comparatively smaller functional gills indicating a mismatch between size and function. It is therefore likely that individual larvae that had survived acidification treatments will suffer from impairments later during ontogeny. Our study highlights important allocation trade‐off between growth and organ development, which is critically important to interpret acidification effects on early life stages of fish.  相似文献   
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Background

The genus Aloe is renowned for its medicinal and cosmetic properties and long history of use. Sixty-three Aloe species occur in Kenya, of which around 50 % are endemic. Several species of aloes are threatened with extinction and knowledge about their use is of major importance for sound conservation strategies. The main aims of this study were to assess the biocultural value of Aloe in Kenya by documenting local uses of aloes and evaluating how the vernacular names reflect the relative importance in different ethnic groups.

Methods

Ethnobotanical and ethnotaxonomical data were collected using field observations and semi-structured interviews. Information was collected by interviewing 63 respondents from nine different ethnic groups, representing different ages, gender and occupations. Statistical analyses were performed using R version 3.1.2.

Results

A total of 19 species of Aloe were found in the study area, of which 16 were used. On the generic level Aloe was easily distinguished. At species level, the local and scientific delimitation were almost identical for frequently used taxa. Aloe secundiflora, with 57 unique use records was the most important species. The two most frequently mentioned Aloe treatments, were malaria and poultry diseases. In our study area neither age nor gender had a significant influence on the level of knowledge of Aloe use. Finally, no correlation was found between extent of use and people’s perception of decrease in local aloe populations. The aloes are highly appreciated and are therefore propagated and transported over large areas when people relocate.

Conclusion

Biocultural value is reflected in the ethnotaxonomy of Aloe in Kenya. Different ethnic groups recognise their most-valued Aloe at the genus level as “the aloe” and add explanatory names for the other species, such as the “spotted aloe” and the “one-legged aloe”. Widespread species of Aloe have the highest number of uses. There is no obvious correlation with high use and decrease in abundance of aloes locally, and we found no compelling evidence for local uses causing devastating damage to populations of the 19 species in use, whereas habitat loss and commercial harvesting appear to be of urgent concern for these important plants.
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Objective

The main objective of this study was to compare disease burden in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (ax-SpA).

Methods

In this cross-sectional study, all the RA (1093), PsA (365) and ax-SpA (333) patients who visited the out-patient clinic of the Hospital of Southern Norway Trust during the year 2013 were included; the RA patients all had a RA diagnosis verified by the treating rheumatologist, the PsA patients all fulfilled the ClASsification for Psoriatic ARthritis (CASPAR) criteria and the ax-SpA patients all fulfilled the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for ax-SpA. Patient-reported health status, demographic variables, medications, and composite scores of disease activity were assessed. The main analyses were performed using General Linear Models adjusted for age, sex and multiple comparisons. Correlation analyses were performed using Spearman’s rho.

Results

The reported pain, joint pain, patient’s global assessment and fatigue were similar in PsA and ax-SpA, but significantly lower in RA. The 28-joint Disease Activity Score (DAS28) (0.3±0.1, p = 0.003), Clinical Disease Activity Index (CDAI) (1.0±0.4, p = 0.028) and Routine Assessment of Patient Index Data 3 (RAPID3) (0.4±0.1, p = 0.004) were all significantly higher in PsA vs. RA. RAPID3 showed moderate to high correlation with DAS28 (rho = 0.521, p<0.001) and CDAI (rho = 0.768, p<0.001) in RA and PsA, and with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (rho = 0.902, p<0.001) and Bath Ankylosing Spondylitis Functional Index (BASFI) (0.865, p<0.001) in ax-SpA and PsA.

Conclusion

In conclusion, patient- reported outcome measures were similar in our population of PsA and ax-SpA patients, but significantly lower for the RA patients. Composite disease activity measures were lower in RA than in PsA and ax-SpA, but the magnitude of these differences was small and probably not of clinical significance. Our study indicates that disease burden in RA, PsA and ax-SpA may be more similar than previously demonstrated.  相似文献   
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Marked endocrine alterations occur after delivery. Most women cope well with these changes, but the postpartum period is associated with an increased risk of depressive episodes. Previous studies of emotion processing have focused on maternal–infant bonding or postpartum depression (PPD), and longitudinal studies of the neural correlates of emotion processing throughout the postpartum period in healthy women are lacking. In this study, 13 women, without signs of post partum depression, underwent fMRI with an emotional face matching task and completed the MADRS-S, STAI-S, and EPDS within 48 h (early postpartum) and 4–6 weeks after delivery (late postpartum). Also, data from a previous study including 15 naturally cycling controls assessed in the luteal and follicular phase of the menstrual cycle was used. Women had lower reactivity in insula, middle frontal gyrus (MFG), and inferior frontal gyrus (IFG) in the early as compared to the late postpartum assessment. Insular reactivity was positively correlated with anxiety in the early postpartum period and with depressive symptoms late postpartum. Reactivity in insula and IFG were greater in postpartum women than in non-pregnant control subjects. Brain reactivity was not correlated with serum estradiol or progesterone levels. Increased reactivity in the insula, IFG, and MFG may reflect normal postpartum adaptation, but correlation with self-rated symptoms of depression and anxiety in these otherwise healthy postpartum women, may also suggest that these changes place susceptible women at increased risk of PPD. These findings contribute to our understanding of the neurobiological aspects of the postpartum period, which might shed light on the mechanisms underlying affective puerperal disorders, such as PPD.  相似文献   
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