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181.
Three new oribatid mite species of the genus Pergalumna (Galumnidae) are described from growing mosses on rocks near a water stream in India. Pergalumna paraclericata sp. n. is very similar morphologically to Carinogalumna clericata (Berlese, 1914), however, it differs from the latter by the structure of lamellar lines and number of notogastral porose areas. Pergalumna minipora sp. n. is very similar morphologically to Pergalumna bifissurata Hammer, 1972, however, it differs from the latter by the body size and the presence of prodorsal ridges and a median pore. Pergalumna paracattienica sp. n. is very similar morphologically to Pergalumna cattienica Ermilov & Anichkin, 2011, however, it differs from the latter by the number of notogastral porose areas and the body integument on the ventral plate. 相似文献
182.
Thermal denaturation and aggregation of apoform of glycogen phosphorylase b. Effect of crowding agents and chaperones
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Tatyana B. Eronina Natalia A. Chebotareva Svetlana G. Roman Sergey Yu. Kleymenov Valentina F. Makeeva Nikolay B. Poliansky Konstantin O. Muranov Boris I. Kurganov 《Biopolymers》2014,101(5):504-516
The effect of protein and chemical chaperones and crowders on thermal stability and aggregation of apoform of rabbit muscle glycogen phosphorylase b (apoPhb) has been studied at 37°C. Proline suppressed heat‐induced loss in ability of apoPhb to reconstitution at 37°C, whereas α‐crystallin did not reveal a protective action. To compare the antiaggregation activity of intact and crosslinked α‐crystallins, an adsorption capacity (AC) of a protein chaperone with respect to a target protein was estimated. This parameter is a measure of the antiaggregation activity. Crosslinking of α‐crystallin results in 11‐fold decrease in the initial AC. The nonlinear character of the relative initial rate of apoPhb aggregation versus the [intact α‐crystallin]/[apoPhb] ratio plot is indicative of the decrease in the AC of α‐crystallin with increasing the [α‐crystallin]/[apoPhb] ratio and can be interpreted as an evidence for dynamic chaperone structure and polydispersity of α‐crystallin–target protein complexes. As for chemical chaperones, a semisaturation concentration of the latter was used as a characteristic of the antiaggregation activity. A decrease in the semisaturation concentration for proline was observed in the presence of the crowders (polyethylene glycol and Ficoll‐70). © 2013 Wiley Periodicals, Inc. Biopolymers 101: 504–516, 2014. 相似文献
183.
Yankovich TL Beresford NA Wood MD Aono T Andersson P Barnett CL Bennett P Brown JE Fesenko S Fesenko J Hosseini A Howard BJ Johansen MP Phaneuf MM Tagami K Takata H Twining JR Uchida S 《Radiation and environmental biophysics》2010,49(4):549-565
Environmental monitoring programs often measure contaminant concentrations in animal tissues consumed by humans (e.g., muscle). By comparison, demonstration of the protection of biota from the potential effects of radionuclides involves a comparison of whole-body doses to radiological dose benchmarks. Consequently, methods for deriving whole-body concentration ratios based on tissue-specific data are required to make best use of the available information. This paper provides a series of look-up tables with whole-body:tissue-specific concentration ratios for non-human biota. Focus was placed on relatively broad animal categories (including molluscs, crustaceans, freshwater fishes, marine fishes, amphibians, reptiles, birds and mammals) and commonly measured tissues (specifically, bone, muscle, liver and kidney). Depending upon organism, whole-body to tissue concentration ratios were derived for between 12 and 47 elements. The whole-body to tissue concentration ratios can be used to estimate whole-body concentrations from tissue-specific measurements. However, we recommend that any given whole-body to tissue concentration ratio should not be used if the value falls between 0.75 and 1.5. Instead, a value of one should be assumed. 相似文献
184.
Ramziya Kiyamova Olga Kostianets Sergey Malyuchik Valeriy Filonenko Vasiliy Usenko Vadym Gurtovyy Yuliya Khozayenko Stepan Antonuk Lloyd Old Ivan Gout 《Molecular biotechnology》2010,46(2):105-112
Medullary breast carcinoma (MBC) is a relatively rare malignancy with heavy lymphocytic infiltration that despite cytologically
anaplastic features and high mitotic index has more favorable prognosis than other types of breast cancer. Lymphocytic infiltration
of tumors reflects ongoing immune response against tumor antigens which could represent a great interest as potential targets
for cancer immunotherapy. The search for MBC antigens by SEREX methodology has not been successful due to a very high titer
of false positive clones, representing immunoglobulin genes. Here, we describe a novel approach for generating cDNA expression
libraries from MBC tumor samples which are depleted of IgG cDNA clones and, therefore, are suitable for the identification
of novel tumor-associated antigens (TAA) by SEREX approach. Modified methodology allowed us to isolate a panel of known and
novel TAA which are currently under further investigation. 相似文献
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187.
Sergey I. Zhadanov Matthew C. Dulik Michael Markley George W. Jennings Jill B. Gaieski George Elias Theodore G. Schurr 《American journal of physical anthropology》2010,142(4):579-589
The name “Wampanoag” means “Eastern People” or “People of the First Light” in the local dialect of the Algonquian language. Once extensively populating the coastal lands and neighboring islands of the eastern United States, the Wampanoag people now consist of two federally recognized tribes, the Aquinnah and Mashpee, the state‐recognized Seaconke Wampanoag tribe, and a number of bands and clans in present‐day southern Massachusetts. Because of repeated epidemics and conflicts with English colonists, including King Philip's War of 1675–76, and subsequent colonial laws forbidding tribal identification, the Wampanoag population was largely decimated, decreasing in size from as many as 12,000 individuals in the 16th century to less than 400, as recorded in 1677. To investigate the influence of the historical past on its biological ancestry and native cultural identity, we analyzed genetic variation in the Seaconke Wampanoag tribe. Our results indicate that the majority of their mtDNA haplotypes belongs to West Eurasian and African lineages, thus reflecting the extent of their contacts and interactions with people of European and African descent. On the paternal side, Y‐chromosome analysis identified a range of Native American, West Eurasian, and African haplogroups in the population, and also surprisingly revealed the presence of a paternal lineage that appears at its highest frequencies in New Guinea and Melanesia. Comparison of the genetic data with genealogical and historical information allows us to reconstruct the tribal history of the Seaconke Wampanoag back to at least the early 18th century. Am J Phys Anthropol 142:579–589, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
188.
Oxygen consumption in Mn-depleted photosystem II (PSII) preparations under continuous and pulsed illumination is investigated. It is shown that removal of manganese from the water-oxidizing complex (WOC) by high pH treatment leads to a 6-fold increase in the rate of O2 photoconsumption. The use of exogenous electron acceptors and donors to PSII shows that in Mn-depleted PSII preparations along with the well-known effect of O2 photoreduction on the acceptor side of PSII, there is light-induced O2 consumption on the donor side of PSII (nearly 30% and 70%, respectively). It is suggested that the light-induced O2 uptake on the donor side of PSII is related to interaction of O2 with radicals produced by photooxidation of organic molecules. The study of flash-induced O2 uptake finds that removal of Mn from the WOC leads to O2 photoconsumption with maximum in the first flash, and its yield is comparable with the yield of O2 evolution on the third flash measured in the PSII samples before Mn removal. The flash-induced O2 uptake is drastically (by a factor of 1.8) activated by catalytic concentration (5-10 μM, corresponding to 2-4 Mn per RC) of Mn2+, while at higher concentrations (> 100 μM) Mn2+ inhibits the O2 photoconsumption (like other electron donors: ferrocyanide and diphenylcarbazide). Inhibitory pre-illumination of the Mn-depleted PSII preparations (resulting in the loss of electron donation from Mn2+) leads to both suppression of flash-induced O2 uptake and disappearance of the Mn-induced activation of the O2 photoconsumption. We assume that the light-induced O2 uptake in Mn-depleted PSII preparations may reflect not only the negative processes leading to photoinhibition but also possible participation of O2 or its reactive forms in the formation of the inorganic core of the WOC. 相似文献
189.
Low‐pH and Al3+ stresses are the major causes of poor plant growth in acidic soils. However, there is still a poor understanding of plant responses to low‐pH and Al3+ toxicity. Low‐pH or combined low‐pH and Al3+ stress was imposed in order to measure rhizosphere pH, ion fluxes, plasma membrane potential and intracellular H+ concentration in distal elongation and mature zones (MZs) along the longitudinal axis of Arabidopsis thaliana roots. Low‐pH stress facilitated H+ influx into root tissues and caused cytoplasmic acidification; by contrast, combined low‐pH/Al3+ treatment either decreased H+ influx in the distal elongation zone (DEZ) or induced H+ efflux in the MZ, leading to cytoplasmic alkalinization in both zones. Low‐pH stress induced an increase in rhizosphere pH in the DEZ, whereas combined low‐pH/Al3+ stress resulted in lower rhizosphere pH in both root zones compared with the low‐pH treatment alone. Low‐pH stress facilitated K+ efflux; the presence of Al3+ diminished K+ efflux or favored K+ influx into root tissues. In both zones, low‐pH treatment induced plasma membrane (PM) depolarization, which was significantly diminished (P≤ 0.05) when combined stresses (low‐pH/100 µM Al3+) were imposed. After 60 min of exposure, low pH caused PM depolarization, whereas low pH/100 µM Al3+ caused PM hyperpolarization. Thus, low pH and Al3+ toxicity differentially affect root tissues and, consequently, the rhizosphere, which might underpin the differential mechanisms of plant adaptation to these abiotic stresses. 相似文献
190.
Mikhail P. Moshkin Eugene A. Novikov Sergey E. Tkachev Valentin V. Vlasov 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(6):620-628
The morbidity of tick‐borne encephalitis (TBE) varies yearly by as much as 10‐fold among the people of Western Siberia. This long‐term variation is dependent on many factors such as the density of the tick populations, the prevalence of TBE virus (TBEV) among sub‐adult ticks, the yearly virulence of the TBEV, and prophylactic measures. Here we highlight the role of small mammal hosts in the circulation of TBEV through the ecosystem. Refining classical models of non‐viremic horizontal transmission, we emphasize the recently understood fact that the physiological and immunological status of the small mammal hosts affects the tick and virus‐host interactions. In addition to its theoretical interest, our approach may lead to some practical improvements in the precision of epidemiological forecasts and perhaps in forestalling the severity of outbreaks of TBE, or, at least, in forewarning medical authorities and the general public of impending TBE outbreaks. 相似文献