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401.
A new coprophilous species, Coprinellus radicellus, is presented and described on the basis of morphological characters and a species phylogeny inferred from ITS1–5.8S–ITS2
and beta-tubulin gene sequences. The species is characterized by lageniform pileo- and caulocystidia, 8- to 11-μm long ellipsoid
basidiospores with a central germ-pore, globose cheilocystidia, an often rooting stipe, the lack of pleurocystidia and velar
elements. These characters distinguish C. radicellus from all other described species in subsection Setulosi. It comes closest to C. brevisetulosus (Arnolds) Redhead, Vilgalys & Moncalvo and C. pellucidus (P. Karst.) Redhead, Vilgalys & Moncalvo both morphologically and phylogenetically, but is distinct from both. Another five
representatives of morphologically recognizable groups of subsection Setulosi were included in the phylogenetic analyses and
found were distinct from C. radicellus, both morphologically and phylogenetically. To date, this new species is known only from Scandinavia, which is surprising
in view of the uniform geographical distributions of most setulose Coprinellus species. A key to coprophilous taxa of Coprinellus with pileo- and caulocystidia is presented. Three new combinations are proposed. 相似文献
402.
Bessy Gutiérrez Christian Muñoz Luis Osorio Krisztina Fehér Tünde-Zita Illyés Zsuzsa Papp Ambati Ashok Kumar Katalin E. Kövér Hernán Sagua Jorge E. Araya Patricio Morales László Szilágyi Jorge González 《Bioorganic & medicinal chemistry letters》2013,23(12):3576-3579
Aromatic oligovalent glycosyl disulfides and some diglycosyl disulfides were tested against three different Trypanosoma cruzi strains. Di-(β-d-galactopyranosyl-dithiomethylene) benzenes 2b and 4b proved to be the most active derivatives against all three strains of cell culture-derived trypomastigotes with IC50 values ranging from 4 to 11 μM at 37 °C. The inhibitory activities were maintained, although somewhat lowered, at a temperature of 4 °C as well. Three further derivatives displayed similar activities against at least one of the three strains. Low cytotoxicities of the active compounds, tested on confluent HeLa, Vero and peritoneal macrophage cell cultures, resulted in significantly higher selectivity indices (SI) than that of the reference drug benznidazole. Remarkably, several molecules of the tested panel strongly inhibited the parasite release from T. cruzi infected HeLa cell cultures suggesting an effect against the intracellular development of T. cruzi amastigotes as well. 相似文献
403.
Tara Pouyani Basma H. Sadaka Suzanne Papp Lana Schaffer 《In vitro cellular & developmental biology. Animal》2013,49(3):178-188
Triiodothyronine (T3) is a thyroid hormone that can have varying effects on skin. In order to assess the effects of T3 on the human dermis, we prepared dermal equivalents using neonatal dermal cells via the process of self-assembly in the presence of differing concentrations of T3. These dermal equivalents were prepared in the absence of serum and a three dimensional matrix allowing for the direct assessment of different concentrations of T3 on dermal extracellular matrix formation. Three different concentrations of T3 were chosen, 20 pM, which is part of the base medium, 0.2 nM T3 and 2 nM T3. We find that self-assembled dermal equivalents formed under these conditions show a progressive “thinning” with increasing T3 concentrations. While we observed no change in total collagen content, inhibition of hyaluronate (HA) synthesis was observed in the 0.2- and 2-nM T3 constructs as compared to the 20-pM construct. Other glycosaminoglycan synthesis was not affected by increasing T3 concentrations. In order to identify the gene(s) responsible for inhibition of HA synthesis in the 2-nM T3 dermal equivalent, we conducted a differential gene array analysis. The results of these experiments demonstrate the differential expression of 40 genes, of these, 34 were upregulated and 6 genes were downregulated. The results from these experiments suggest that downregulation of HAS2 may be responsible for inhibition of hyaluronate synthesis in the self-assembled 2-nM T3 human dermal matrix. 相似文献
404.
Tamás Papp Csaba Vágvölgyi Zoltán Kerényi Ágnes Nagy Themis J. Michailides 《Antonie van Leeuwenhoek》1997,72(3):167-173
Mucor piriformis can cause postharvest decay in various fruits and vegetables stored at low temperatures. Thirty isolates of this fungus, collected from infected fruit, were subjected to random amplified polymorphic DNA (RAPD) analysis. Seven different 10-bp primers were used to determine the type and extent of intraspecific genetic polymorphisms. Nineteen composite amplification types were identified, indicating a higher degree of variability than found in previous isoenzyme studies. Numerical analysis with the UPGMA technique revealed three clusters, which correlated with the mating competency of the isolates or their place of origin. These results demonstrate that RAPD analysis can identify isolates and subspecific populations of M. piriformis. 相似文献
405.
406.
Thermal sensitivity of a Neotropical amphibian (Engystomops pustulosus) and its vulnerability to climate change 下载免费PDF全文
Hilton M. Oyamaguchi Pacific Vo Kiran Grewal Robert Do Eugene Erwin Narin Jeong Katherine Tse Chantelle Chen Morgan Miyake Alice Lin Marcos Gridi‐Papp 《Biotropica》2018,50(2):326-337
A species’ thermal sensitivity and its exposure to climate variation are key components in the prediction of its vulnerability to climate change. We tested the thermal sensitivity of a tropical amphibian that lives in a mild constant climate in which the thermal tolerance range is expected to closely match the experienced environmental temperature. The air temperature that this species is exposed to varies between 21.9 and 31.6°C with an annual mean of 27.2°C. We estimated the microhabitat water temperature variation under vegetation shade, which buffers the temperature by 1.8°C in relation to that of the air, and with open canopy, where the water was 1.9°C warmer than the air temperature. With broods of tadpoles split into five treatments (15°C, 21°C, 28°C, 31°C, and 33°C), we estimated the critical thermal maximum (CTMax) and critical thermal minimum (CTMin) after at least 7 days of acclimation. Both CTMax (42.3°C) and CTMin (11.8°C) were more extreme than the temperature range estimated for the field. We estimated the optimum temperature (To = 28.8°C) and the thermal performance breadth (range: 23.3–34.1°C) based on growth rate (g/day). The animals were able to acclimate more extensively to cold than to warm temperatures. These performance curve traits closely matched the air temperature. The estimated vulnerability varied according to the microhabitat prediction model used. The combination of tadpole data on thermal sensitivity and macro‐ and microhabitat variation provides a necessary framework to understand the effects of climate change on tropical amphibians. 相似文献
407.
Nardai G Stadler K Papp E Korcsmáros T Jakus J Csermely P 《Biochemical and biophysical research communications》2005,334(3):787-795
Changes in assisted protein folding are largely unexplored in diabetes. In the present studies, we have identified a reductive shift in the redox status of rat liver microsomes after 4 weeks of streptozotocin-induced diabetes. This change was reflected by a significant increase in the total- and protein-sulfhydryl content, as well as in the free sulfhydryl groups of the major protein disulfide isomerases (PDIs), the 58 kDa PDI and the 57 kDa ERp57 but not other chaperones. A parallel decrease of the protein-disulfide oxidoreductase activity was detected in the microsomal fraction of diabetic livers. The oxidant of PDI, Ero1-Lalpha showed a more oxidized status in diabetic rats. Our results reveal major changes in the redox status of the endoplasmic reticulum and its redox chaperones in diabetic rats, which may contribute to the defective protein secretion of the diabetic liver. 相似文献
408.
The dichroism of purple membrane suspension was measured in dc and ac electric fields. From these measurements three parameters can be obtained: the permanent dipole moment, μ, the electrical polarizability, α, and the retinal angle, δ, (relative to the membrane normal). The functional dependence of the dichroism on the electric field is analyzed. There is a small decrease (~2°) in retinal angle going from dark adapted to the light adapted form. No measurable difference in μ, α, and δ was found under the photocycle. The dichroism was measured in two different salt solutions (KCl and CaCl2) in the range 0-10 mM. The retinal angle increases from 64° to 68° with increasing ionic strength going through a minimum. This is attributed to the changing (decreasing) inner electric field in the membrane. The polarizability, α, consists of two parts. One component is related to the polarization of the purple membrane and the second component to the ionic cloud. The second component decreases with ion concentration approximately as κ-3 (κ is the Debye parameter) in agreement with a model calculation for the polarization of the ionic cloud. The origin of the slightly ionic strength dependent permanent dipole moment is not well understood. 相似文献
409.
Benedek?Papp Tibor?T?r?k Erzsébet?Sándor Erzsébet?Fekete Michel?Flipphi Levente?KaraffaEmail author 《Folia microbiologica》2016,61(3):191-198
Nitrosomonas europaea is a chemolithoautotrophic nitrifier, a gram-negative bacterium that can obtain all energy required for growth from the oxidation of ammonia to nitrite, and this may be beneficial for various biotechnological and environmental applications. However, compared to other bacteria, growth of ammonia oxidizing bacteria is very slow. A prerequisite to produce high cell density N. europaea cultures is to minimize the concentrations of inhibitory metabolic by-products. During growth on ammonia nitrite accumulates, as a consequence, N. europaea cannot grow to high cell concentrations under conventional batch conditions. Here, we show that single-vessel dialysis membrane bioreactors can be used to obtain substantially increased N. europaea biomasses and substantially reduced nitrite levels in media initially containing high amounts of the substrate. Dialysis membrane bioreactor fermentations were run in batch as well as in continuous mode. Growth was monitored with cell concentration determinations, by assessing dry cell mass and by monitoring ammonium consumption as well as nitrite formation. In addition, metabolic activity was probed with in vivo acridine orange staining. Under continuous substrate feed, the maximal cell concentration (2.79?×?1012/L) and maximal dry cell mass (0.895 g/L) achieved more than doubled the highest values reported for N. europaea cultivations to date. 相似文献
410.
Dniel Lszl Vidcs Zoltn Verb Renta Boz Lili Borbla Flink Hilda Polynka Istvn Balzs Nmeth Szilrd Pliska Benjamin Tams Papp Mt Manczinger Rbert Gspr Seyedmohsen Mirdamadi Lajos Kemny Zsuzsanna Bata-Csrg 《Pigment cell & melanoma research》2022,35(1):38-51
We previously described a novel in vitro culture technique for dedifferentiated human adult skin melanocytes. Melanocytes cultured in a defined, cholera toxin and PMA free medium became bipolar, unpigmented, and highly proliferative. Furthermore, TRP-1 and c-Kit expression disappeared and EGFR receptor and nestin expression were induced in the cells. Here, we further characterized the phenotype of these dedifferentiated cells and by comparing them to mature pigmented melanocytes we detected crucial steps in their phenotype change. Our data suggest that normal adult melanocytes easily dedifferentiate into pluripotent stem cells given the right environment. This dedifferentiation process described here for normal melanocyte is very similar to what has been described for melanoma cells, indicating that phenotype switching driven by environmental factors is a general characteristic of melanocytes that can occur independent of malignant transformation. 相似文献