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191.
Increased Dkk‐1 plasma levels may discriminate disease subtypes in myeloproliferative neoplasms 下载免费PDF全文
Cristina Mambet Laura Necula Simona Mihai Lilia Matei Coralia Bleotu Mihaela Chivu‐Economescu Oana Stanca Aurelia Tatic Nicoleta Berbec Cristiana Tanase Carmen C. Diaconu 《Journal of cellular and molecular medicine》2018,22(8):4005-4011
Alterations in the bone marrow niche induced by abnormal production of cytokines and other soluble factors have been associated with disease progression in classical BCR‐ABL1 negative myeloproliferative neoplasms (MPN). Variations in circulating proteins might reflect local disease processes and plasma proteome profiling could serve to identify possible diagnostic and prognostic biomarkers. We employed a human cytokine array to screen for 105 distinct analytes in pooled plasma samples obtained from untreated young MPN patients (<35 years) with different clinical phenotypes and driver mutations, as well as from healthy individuals. Among molecules that exhibited significantly increased levels in MPN patients versus controls, the top of the list was represented by Dickkopf‐related protein 1 (Dkk‐1), which also showed the highest potential for discrimination between MPN subtypes. In the next step, a quantitative ELISA was used to measure plasma Dkk‐1 levels in 30 young‐onset MPN—10 essential thrombocythemia (ET), 10 polycythemia vera (PV), 10 pre‐fibrotic primary myelofibrosis (pre‐PMF)—and 10 controls. The results suggested that plasma Dkk‐1 levels could differentiate ET from pre‐PMF, in JAK2 V617F‐positive as well as in CALR‐positive patients, and also ET from PV in JAK2 V617F‐positive patients. 相似文献
192.
Anna Śmiech Brygida Ślaska Wojciech Łopuszyński Agnieszka Jasik Diana Bochyńska Roman Dąbrowski 《Acta veterinaria Scandinavica》2018,60(1):70
Background
The degree of differentiation of mast cell tumours (MCTs) is the most important feature and reflects the morphological characteristics and metastatic potential of the tumour and its likely response to treatment and the prognosis. The aim of this study was to epidemiologically analyse the risk of MCT development in dogs according to breed, age, sex, size and anatomical location of the tumour using the Kiupel grading system. The analysis involved 492 dogs selected based on a histopathological assessment of 2763 canine skin tumours. A logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals.Results
Mast cell tumours accounted for 17.8% of all diagnosed canine skin tumours. The highest risk of high-grade MCTs was noted in the Shar-Pei (OR 28.18, P?<?0.001) and Weimaraner (OR 6.45, P?=?0.023). The highest risk of low-grade MCTs was determined in the Boxer (OR 6.72, P?<?0.001), and Pug (OR 6.13, P?=?0.027). The scrotum (OR 31.72, P?<?0.001), inguinal area (OR 17.69, P?<?0.001) and axilla (OR 6.30, P?<?0.001) had the highest risk of high-grade MCTs. The risk of high-grade MCTs increased with age and peaked in the oldest dogs, aged 11–16 years (OR 9.55, P?<?0.001). A higher risk of low-grade tumours was noted in younger dogs (aged 4–6 years) (OR 8.54, P?<?0.001) and females (OR 1.43, P?=?0.001). Statistical analysis further revealed a higher risk of both low (OR 3.47, P?<?0.001) and high-grade MCTs (OR 1.71, P?=?0.006) in medium-sized dogs.Conclusions
This study demonstrated relationships between Kiupel grading system and phenotypic traits, age and location of canine MCTs confirming the complex biological nature of this tumour.193.
Guo W Keckesova Z Donaher JL Shibue T Tischler V Reinhardt F Itzkovitz S Noske A Zürrer-Härdi U Bell G Tam WL Mani SA van Oudenaarden A Weinberg RA 《Cell》2012,148(5):1015-1028
194.
This study examined the formation of morphological defences by two coexisting Daphnia species, the large-sized D. pulicaria (2 mm) and the small-sized D. mendotae (1.4 mm), in response to the presence of young-of-the-year (YOY) yellow perch (Perca flavescens) and invertebrate predators (Chaoborus, Leptodora) during summer in a mesotrophic lake. We hypothesized that due to differential size-selective predation risk by YOY fish
and invertebrates, the large-sized and the small-sized Daphnia species would show different morphological responses to predation threats. We followed changes in two morphological traits
(relative length of the tail spine in D. pulicaria and of the helmet in D. mendotae) among different periods during summer according to YOY fish and invertebrate predation. We defined four YOY fish predation
periods based on the presence of YOY perch in the pelagic zone of the lake and the relative abundance of Daphnia preys in their gut contents, and two invertebrate predation periods based on exclusive or mutual occurrence of the invertebrate
predators. The large-sized (D. pulicaria) and the small-sized (D. mendotae) species showed different morphological responses to YOY fish and invertebrate predators, respectively. The tail spine ratio
of the juveniles and adults of D. pulicaria did not change in response to YOY fish predation or to invertebrate predation. A gradual increase in the helmet ratio was
observed in the small-sized D. mendotae over the summer period. This change was related to the co-occurrence of the invertebrate predators (Chaoborus and Leptodora) and to YOY fish predation. The warmer temperature cannot be accounted for helmet elongation since it was constant across
depths, and not related with the co-occurrence of D. mendotae and YOY perch.
Guest editor: Piet Spaak
Cladocera: Proceedings of the 7th International Symposium on Cladocera 相似文献
195.
Bartosz J. Płachno Małgorzata Stpiczyńska Piotr Świątek Kevin L. Davies 《Protoplasma》2016,253(6):1463-1473
Flowers of sexually deceptive taxa generally possess a set of morphological and physiological characters that mimic their insect pollinators. These characters often include a specific insect-like floral configuration, together with scent glands (osmophores) that produce fragrances which chemically resemble insect sex pheromones. Furthermore, these flowers tend not to produce pollinator food rewards. According to some authors, flowers of the Australian bladderwort Utricularia dunlopii (and species of the Utricularia capilliflora complex) resemble insects, and pollination perhaps occurs by pseudocopulation. The aims of this paper are to compare the structure and distribution of floral glandular trichomes in the Australian carnivorous plant U. dunlopii with those of closely related species assigned to the same section and to discuss their putative function. Floral tissues of U. dunlopii P. Taylor, Utricularia paulinae Lowrie, Utricularia dichotoma Labill. and Utricularia uniflora R.Br. (section Pleiochasia) were investigated using light microscopy, scanning electron microscopy, transmission electron microscopy and histochemistry. In U. dunlopii, two long, erect, filiform appendages arising from the upper lip of the corolla, together with three arising from the lower lip, bear numerous glandular trichomes that may function as osmophores. In other species, such as U. uniflora and U. paulinae, glandular papillae on the corolla palate may also function as osmophores. The floral anatomical and morphological organisation of U. dunlopii differs from that of the other investigated species, indicating that its insect pollinators are also likely to differ. Morphological and ultrastructural observations, while generally contributing to our understanding of the flower of U. dunlopii, do not refute the possibility that pollination here may occur by pseudocopulation. Further field-based investigations, however, are now necessary to test this hypothesis. 相似文献
196.
The mechanical pressure difference across the bacterial cellulose membrane located in a horizontal plane causes asymmetry of voltage measured between electrodes immersed in KCl solutions symmetrically on both sides of the membrane. For all measurements, KCl solution with lower concentration was above the membrane. In configuration of the analyzed membrane system, the concentration boundary layers (CBLs) are created only by molecular diffusion. The voltages measured in the membrane system in concentration polarization conditions were compared with suitable voltages obtained from the model of diffusion through CBLs and ion transport through the membrane. An increase of difference of mechanical pressure across the membrane directed as a difference of osmotic pressure always causes a decrease of voltage between the electrodes in the membrane system. In turn, for mechanical pressure difference across the membrane directed in an opposite direction to the difference of osmotic pressure, a peak in the voltage as a function of mechanical pressure difference is observed. An increase of osmotic pressure difference across the membrane at the initial moment causes an increase of the maximal value of the observed peak and a shift of this peak position in the direction of higher values of the mechanical pressure differences across the membrane. 相似文献
197.
Transbilayer Colocalization of Lipid Domains Explained via Measurement of Strong Coupling Parameters
Matthew?C. Blosser Aurelia?R. Honerkamp-Smith Tao Han Mikko Haataja Sarah?L. Keller 《Biophysical journal》2015,109(11):2317-2327
When micron-scale compositional heterogeneity develops in membranes, the distribution of lipids on one face of the membrane strongly affects the distribution on the other. Specifically, when lipid membranes phase separate into coexisting liquid phases, domains in each monolayer leaflet of the membrane are colocalized with domains in the opposite leaflet. Colocalized domains have never been observed to spontaneously move out of registry. This result indicates that the lipid compositions in one leaflet are strongly coupled to compositions in the opposing leaflet. Predictions of the interleaflet coupling parameter, Λ, vary by a factor of 50. We measure the value of Λ by applying high shear forces to supported lipid bilayers. This causes the upper leaflet to slide over the lower leaflet, moving domains out of registry. We find that the threshold shear stress required to deregister domains in the upper and lower leaflets increases with the inverse length of domains. We derive a simple, closed-form expression relating the threshold shear to Λ, and find Λ = 0.016 ± 0.004 kBT/nm2. 相似文献
198.
In present study, bank voles Clethrionomys glareolus were peritioneally injected with different doses of cadmium, 0, 1.5, 3.0 mg Cd/kg body mass. Animals were sacrificed on the
21st day after cadmium exposure and the liver and kidney were obtained for cadmium, zinc and iron analysis using atomic absorption
spectrometry. Results showed that cadmium had accumulated in the tissues according to dosage and sex. Cadmium affected the
survival and body masses of dosed females. Cadmium decreased the iron concentrations in the liver of voles, whereas zinc concentrations
increased in both the kidney and liver. 相似文献
199.
Mitochondrial DNA (mtDNA) follows direct maternal inheritance and, as such, can be used in phylogenetic studies to determine a human lineage tree. The presence of common polymorphisms allows a classification of mtDNA in haplogroups and sub-haplogroups, according to the branch they belong to. Thanks to the rapidly growing number of mtDNA sequences available, this classification is being corrected and redefined to be more accurate. In parallel with this process, several studies are trying to identify an association between common mtDNA polymorphisms and common complex traits, as hypothesized by the common disease-common variant theory. Here we review the associations already reported with the main age-related complex diseases and we identify the critical points (sample size, size of the recruiting area, careful matching between cases and controls regarding geographical origin and ethnicity, data quality checking) to be taken in account in planning such studies. On the whole, this research area is opening a new perspective as an important component of "mitochondrial medicine", capable of identifying new molecular targets for the diagnosis, prevention and treatment of common complex diseases. 相似文献
200.