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131.
Nicole Nigro Karin Wildi Christian Mueller Philipp Schuetz Beat Mueller Felix Fluri Mirjam Christ-Crain Mira Katan 《PloS one》2014,9(7)
Background
We analyzed the prognostic value of b-type natriuretic peptide (BNP) and sensitive cardiac Troponin (s-cTnI) in patients with ischemic stroke or transient ischemic attack (TIA) and their significance in predicting stroke aetiology.Methods
In a prospectively enrolled cohort we measured BNP and s-cTnI levels upon admission. Primary endpoints were mortality, unfavorable functional outcome and stroke recurrence after 90 days and after 12 months. Secondary endpoint was cardioembolic aetiology.Results
In 441 patients BNP but not s-cTnI remained an independent predictor for death with an adjusted HR of 1.2 (95% CI 1.1–1.4) after 90 days and 1.2 (95% CI 1.0–1.3) after one year. The comparison of the Area under Receiver Operating Characteristic (AUROC) of model A (age, NIHSS) and model B (age, NIHSS, BNP) showed an improvement in the prediction of mortality (0.85 (95% CI 0.79–0.90) vs. 0.86 (95% CI 0.81–0.92), Log Rank p = 0.004). Furthermore the category free net reclassification improvement (cfNRI) when adding BNP to the multivariate model was 57.5%, p<0.0001. For the prediction of functional outcome or stroke recurrence both markers provided no incremental value. Adding BNP to a model including age, atrial fibrillation and heart failure lead to a higher discriminatory accuracy for identification of cardioembolic stroke than the model without BNP (AUC 0.75 (95% CI 0.70–0.80) vs. AUC 0.79, (95% CI 0.75–0.84), p = 0.008).Conclusion
BNP is an independent prognostic maker for overall mortality in patients with ischemic stroke or TIA and may improve the diagnostic accuracy to identify cardioembolic aetiology.Trial Registration
ClinicalTrials.gov NCT00390962相似文献132.
133.
ABSTRACT: BACKGROUND: Appendicular osteosarcoma is the most common malignant primary canine bone tumor. When treated by amputation or tumor removal alone, median survival times (MST) do not exceed 5 months, with the majority of dogs suffering from metastatic disease. This period can be extended with adequate local intervention and adjuvant chemotherapy, which has become common practice. Several prognostic factors have been reported in many different studies, e.g. age, breed, weight, sex, neuter status, location of tumor, serum alkaline phosphatase (SALP), bone alkaline phosphatase (BALP), infection, percentage of bone length affected, histological grade or histological subtype of tumor. Most of these factors are, however, only reported as confounding factors in larger studies. Insight in truly significant prognostic factors at time of diagnosis may contribute to tailoring adjuvant therapy for individual dogs suffering from osteosarcoma.The objective of this study was to systematically review the prognostic factors that are described for canine appendicular osteosarcoma and validate their scientific importance. RESULTS: A literature review was performed on selected studies and eligible data were extracted. Meta-analyses were done for two of the three selected possible prognostic factors (SALP and location), looking at both survival time (ST) and disease free interval (DFI). The third factor (age) was studied in a qualitative manner. Both elevated SALP level and the (proximal) humerus as location of the primary tumor are significant negative prognostic factors for both ST and DFI in dogs with appendicular osteosarcoma. Increasing age was associated with shorter ST and DFI, however, was not statistically significant because information of this factor was available in only a limited number of papers. CONCLUSIONS: Elevated SALP and proximal humeral location are significant negative prognosticators for canine osteosarcoma. 相似文献
134.
Florentina C. Kunseler Mirjam Oosterman Marleen H. M. de Moor Marije L. Verhage Carlo Schuengel 《PloS one》2016,11(2)
This study tested experimentally whether the combination of a history of childhood abuse and confrontation with difficult infant temperament is associated with negative changes in parenting self-efficacy. First-time pregnant women (N = 243) participated in the Adult Attachment Interview, which was used to assess the occurrence of abuse by parents in childhood and unresolved representations, and completed a task asking them to respond to infant cries. Sixty of the 243 participants (25%) experienced childhood abuse, mostly physical or sexual. The task simulated infant temperamental difficulty by manipulating soothing success in order to reflect an easy-to-soothe (80% soothing success) and a difficult-to-soothe infant (20% soothing success). Both after baseline and after each of the two stimulus series women assessed their parenting self-efficacy. Women who reported childhood abuse did not differ from women who reported no childhood abuse in parenting self-efficacy at baseline or in response to the easy-to-soothe infant (relative to baseline), but decreased more in parenting self-efficacy following the difficult-to-soothe infant. Effects did not vary according to resolution of trauma. These findings suggest that in response to infant temperamental difficulty, women who experienced childhood abuse may more easily lose confidence in their parenting abilities, which underlines the importance of preparing at-risk women for the possible challenges that come along with parenthood. 相似文献
135.
Alice Classen Marcell K. Peters Stefan W. Ferger Maria Helbig-Bonitz Julia M. Schmack Genevieve Maassen Matthias Schleuning Elisabeth K. V. Kalko Katrin B?hning-Gaese Ingolf Steffan-Dewenter 《Proceedings. Biological sciences / The Royal Society》2014,281(1779)
Wild animals substantially support crop production by providing ecosystem services, such as pollination and natural pest control. However, the strengths of synergies between ecosystem services and their dependencies on land-use management are largely unknown. Here, we took an experimental approach to test the impact of land-use intensification on both individual and combined pollination and pest control services in coffee production systems at Mount Kilimanjaro. We established a full-factorial pollinator and vertebrate exclosure experiment along a land-use gradient from traditional homegardens (agroforestry systems), shaded coffee plantations to sun coffee plantations (total sample size = 180 coffee bushes). The exclusion of vertebrates led to a reduction in fruit set of ca 9%. Pollinators did not affect fruit set, but significantly increased fruit weight of coffee by an average of 7.4%. We found no significant decline of these ecosystem services along the land-use gradient. Pest control and pollination service were thus complementary, contributing to coffee production by affecting the quantity and quality of a major tropical cash crop across different coffee production systems at Mount Kilimanjaro. 相似文献
136.
Bombesin-like peptides as well as receptor-independent activators were tested for their effect on gastrin release from acutely dispersed rat gastric G-cells. The amphibian peptide bombesin as well as its mammalian analogues neuromedin B and neuromedin C stimulated gastrin release. Maximal responses were achieved with 10(-9) M bombesin (191.0 +/- 16.8% of basal release), 10(-8) M neuromedin C(205.9 +/- 17.6%) and 10(-7) M neuromedin B (162.2 +/- 10.4%), respectively. The phorbol ester 12-O-tetradecanoyl-phorbol 13-acetate (TPA) and the synthetic diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG) are receptor-independent activators of the protein kinase C. Both TPA (10(-6) M) and OAG (10(-5) M) stimulated gastrin release to 214.0 +/- 29.3% and 198.2 +/- 20.8% of basal, respectively. Calcium ionophore A23187 (10(-5) M) was the most effective stimulant tested (364.7 +/- 39.6%). Its effect was reversed by the calmodulin antagonist W 7 (10(-6)-10(-5) M). Finally, forskolin (10(-5) M), a direct activator of cAMP-formation, as well as the cAMP-analogue dbcAMP (10(-3) M) induced gastrin release. IN conclusion, neuromedin B is less potent and less effective than neuromedin C and bombesin in stimulating rat gastric G-cells. In addition, gastrin release is activated by calcium- and phospholipid-dependent as well as by cAMP-induced cellular signal transduction mechanisms. 相似文献
137.
The influence of several meteorological parameters on acute myocardial infarction (AMI) incidences with immediately and/or delayed effects has been widely reported. It remains unknown whether the individual AMI subtypes reveal similar patterns. To date, generally seasonal variation in ST elevation MI (STEMI) has been investigated. However, these approaches couldn’t detect the effects of changes in multiple meteorological variables on STEMI incidence within a specific season. Therefore, the aim of our study is to explore immediate, delayed and cumulative effects of average daily temperature, atmospheric pressure and humidity on nation-wide STEMI hospital admissions. We linked daily hospitals’ STEMI admission data with meteorological stations’ data according to the patient’s permanent residence. Subsequently, a multivariate analysis based on a main effect generalised linear model, assuming a log-link function with a Poisson distribution, was conducted. With the help of lags, we were able to analyse delayed effects, while the cumulative effects of specific meteorological variables were analysed utilising time windows. As a result, we confirmed immediate and delayed negative effect of low temperature and low relative humidity for all observed lags as well as cumulative average effects of low temperature and low relative humidity for all observed time windows. However, no delayed, single-day effect for atmospheric pressure was detected. Nevertheless, the cumulative average effect was confirmed in all time windows suggesting that prolonged low pressure influences the incidence of STEMI. A novelty of our approach is the comparative examination of immediate, delayed and cumulative effect of specific meteorological variables on the incidence of STEMI. This approach enables us to gain a new insight into the phenomenon studied. 相似文献
138.
Frédéric Partensky Daniella Mella-Flores Laurence Garczarek Mirjam Czjzek Dominique Marie Eva Kotabová Kristina Felcmanová Ondřej Prášil 《Photosynthesis research》2018,138(1):57-71
The extrinsic PsbU and PsbV proteins are known to play a critical role in stabilizing the Mn4CaO5 cluster of the PSII oxygen-evolving complex (OEC). However, most isolates of the marine cyanobacterium Prochlorococcus naturally miss these proteins, even though they have kept the main OEC protein, PsbO. A structural homology model of the PSII of such a natural deletion mutant strain (P. marinus MED4) did not reveal any obvious compensation mechanism for this lack. To assess the physiological consequences of this unusual OEC, we compared oxygen evolution between Prochlorococcus strains missing psbU and psbV (PCC 9511 and SS120) and two marine strains possessing these genes (Prochlorococcus sp. MIT9313 and Synechococcus sp. WH7803). While the low light-adapted strain SS120 exhibited the lowest maximal O2 evolution rates (Pmax per divinyl-chlorophyll a, per cell or per photosystem II) of all four strains, the high light-adapted strain PCC 9511 displayed even higher PChlmax and PPSIImax at high irradiance than Synechococcus sp. WH7803. Furthermore, thermoluminescence glow curves did not show any alteration in the B-band shape or peak position that could be related to the lack of these extrinsic proteins. This suggests an efficient functional adaptation of the OEC in these natural deletion mutants, in which PsbO alone is seemingly sufficient to ensure proper oxygen evolution. Our study also showed that Prochlorococcus strains exhibit negative net O2 evolution rates at the low irradiances encountered in minimum oxygen zones, possibly explaining the very low O2 concentrations measured in these environments, where Prochlorococcus is the dominant oxyphototroph. 相似文献
139.
Frommhagen Matthias Westphal Adrie H. Hilgers Roelant Koetsier Martijn J. Hinz Sandra W. A. Visser Jaap Gruppen Harry van Berkel Willem J. H. Kabel Mirjam A. 《Applied microbiology and biotechnology》2018,102(3):1281-1295
Applied Microbiology and Biotechnology - Lytic polysaccharide monooxygenases (LPMOs) have recently been shown to significantly enhance the degradation of recalcitrant polysaccharides and are of... 相似文献
140.
Benedikt Gehr Elizabeth J. Hofer Mirjam Pewsner Andreas Ryser Eric Vimercati Kristina Vogt Lukas F. Keller 《Ecology and evolution》2018,8(1):109-119
Predator‐prey theory predicts that in the presence of multiple types of predators using a common prey, predator facilitation may result as a consequence of contrasting prey defense mechanisms, where reducing the risk from one predator increases the risk from the other. While predator facilitation is well established in natural predator‐prey systems, little attention has been paid to situations where human hunters compete with natural predators for the same prey. Here, we investigate hunting‐mediated predator facilitation in a hunter‐predator‐prey system. We found that hunter avoidance by roe deer (Capreolus capreolus) exposed them to increase predation risk by Eurasian lynx (Lynx lynx). Lynx responded by increasing their activity and predation on deer, providing evidence that superadditive hunting mortality may be occurring through predator facilitation. Our results reveal a new pathway through which human hunters, in their role as top predators, may affect species interactions at lower trophic levels and thus drive ecosystem processes. 相似文献