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101.
Kararizou EG Manta P Kalfakis N Gkiatas KA Vassilopoulos D 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(3):148-152
OBJECTIVE: To determine the morphologic and the morphometrical features of spindles in biopsies of patients with different types of muscular dystrophy and investigate the possible involvement of the spindle in the pathologic process of these diseases. STUDY DESIGN: The following variables were studied in biopsy specimens from 10 patients with Duchenne or Becker dystrophy, 9 with limb-girdle dystrophy, 3 with congenital dystrophy and 3 with facioscapulohumeral dystrophy: diameter and area of spindle; thickness of the capsule; number, diameter and area of intrafusal fibers; and number and area of nuclei. RESULTS: The statistical evaluation of the data showed significant differences regarding the thickness of the capsule, which was greater in patients than in controls, while the diameter and the area of the fibers were all smaller in patients than in controls. The area of nuclei of fibers was increased; this was a common feature for all types of muscular dystrophy. CONCLUSION: These findings indicate that the spindle possibly participates in the pathologic process of different types of muscular dystrophies. 相似文献
102.
Oxidative stress biomarkers responses to physical overtraining: implications for diagnosis 总被引:1,自引:0,他引:1
Margonis K Fatouros IG Jamurtas AZ Nikolaidis MG Douroudos I Chatzinikolaou A Mitrakou A Mastorakos G Papassotiriou I Taxildaris K Kouretas D 《Free radical biology & medicine》2007,43(6):901-910
Overtraining syndrome is characterized by declining performance and transient inflammation following periods of severe training with major health implications for the athletes. Currently, there is no single diagnostic marker for overtraining. The present investigation examined the responses of oxidative stress biomarkers to a resistance training protocol of progressively increased and decreased volume/intensity. Twelve males (21.3+/-2.3 years) participated in a 12-week resistance training consisting of five 3-week periods (T1, 2 tones/week; T2, 8 tones/week; T3, 14 tones/week; T4, 2 tones/week), followed by a 3-week period of complete rest. Blood/urine samples were collected at baseline and 96 h following the last training session of each period. Performance (strength, power, jumping ability) increased after T2 and declined thereafter, indicating an overtraining response. Overtraining (T3) induced sustained leukocytosis, an increase of urinary isoprostanes (7-fold), TBARS (56%), protein carbonyls (73%), catalase (96%), glutathione peroxidase, and oxidized glutathione (GSSG) (25%) and a decline of reduced glutathione (GSH) (31%), GSH/GSSG (56%), and total antioxidant capacity. Isoprostanes and GSH/GSSG were highly (r=0.764-0.911) correlated with performance drop and training volume increase. In conclusion, overtraining induces a marked response of oxidative stress biomarkers which, in some cases, was proportional to training load, suggesting that they may serve as a tool for overtraining diagnosis. 相似文献
103.
An integrative approach combining ion mobility mass spectrometry,X-ray crystallography,and nuclear magnetic resonance spectroscopy to study the conformational dynamics of α1-antitrypsin upon ligand binding 下载免费PDF全文
Mun Peak Nyon Tanya Prentice Jemma Day John Kirkpatrick Ganesh N Sivalingam Geraldine Levy Imran Haq James A Irving David A Lomas John Christodoulou Bibek Gooptu Konstantinos Thalassinos 《Protein science : a publication of the Protein Society》2015,24(8):1301-1312
Native mass spectrometry (MS) methods permit the study of multiple protein species within solution equilibria, whereas ion mobility (IM)-MS can report on conformational behavior of specific states. We used IM-MS to study a conformationally labile protein (α1-antitrypsin) that undergoes pathological polymerization in the context of point mutations. The folded, native state of the Z-variant remains highly polymerogenic in physiological conditions despite only minor thermodynamic destabilization relative to the wild-type variant. Various data implicate kinetic instability (conformational lability within a native state ensemble) as the basis of Z α1-antitrypsin polymerogenicity. We show the ability of IM-MS to track such disease-relevant conformational behavior in detail by studying the effects of peptide binding on α1-antitrypsin conformation and dynamics. IM-MS is, therefore, an ideal platform for the screening of compounds that result in therapeutically beneficial kinetic stabilization of native α1-antitrypsin. Our findings are confirmed with high-resolution X-ray crystallographic and nuclear magnetic resonance spectroscopic studies of the same event, which together dissect structural changes from dynamic effects caused by peptide binding at a residue-specific level. IM-MS methods, therefore, have great potential for further study of biologically relevant thermodynamic and kinetic instability of proteins and provide rapid and multidimensional characterization of ligand interactions of therapeutic interest.PDB Code(s): 4PYW 相似文献
104.
N. Helge Meyer Hubert Mayerhofer Konstantinos Tripsianes Silke Blindow Daniela Barths Astrid Mewes Thomas Weimar Thies K?hli Steffen Bade Tobias Madl Andreas Frey Helmut Haas Jochen Mueller-Dieckmann Michael Sattler Gabriele Schramm 《The Journal of biological chemistry》2015,290(36):22111-22126
The IL-4-inducing principle from Schistosoma mansoni eggs (IPSE/α-1), the major secretory product of eggs from the parasitic worm S. mansoni, efficiently triggers basophils to release the immunomodulatory key cytokine interleukin-4. Activation by IPSE/α-1 requires the presence of IgE on the basophils, but the detailed molecular mechanism underlying activation is unknown. NMR and crystallographic analysis of IPSEΔNLS, a monomeric IPSE/α-1 mutant, revealed that IPSE/α-1 is a new member of the βγ-crystallin superfamily. We demonstrate that this molecule is a general immunoglobulin-binding factor with highest affinity for IgE. NMR binding studies of IPSEΔNLS with the 180-kDa molecule IgE identified a large positively charged binding surface that includes a flexible loop, which is unique to the IPSE/α-1 crystallin fold. Mutational analysis of amino acids in the binding interface showed that residues contributing to IgE binding are important for IgE-dependent activation of basophils. As IPSE/α-1 is unable to cross-link IgE, we propose that this molecule, by taking advantage of its unique IgE-binding crystallin fold, activates basophils by a novel, cross-linking-independent mechanism. 相似文献
105.
106.
Silvas J Prince Li Song Dan Qiu Joao V Maldonado dos Santos Chenglin Chai Trupti Joshi Gunvant Patil Babu Valliyodan Tri D Vuong Mackensie Murphy Konstantinos Krampis Dominic M Tucker Ruslan Biyashev Anne E Dorrance MA Saghai Maroof Dong Xu J Grover Shannon Henry T Nguyen 《BMC genomics》2015,16(1)
Background
Root system architecture is important for water acquisition and nutrient acquisition for all crops. In soybean breeding programs, wild soybean alleles have been used successfully to enhance yield and seed composition traits, but have never been investigated to improve root system architecture. Therefore, in this study, high-density single-feature polymorphic markers and simple sequence repeats were used to map quantitative trait loci (QTLs) governing root system architecture in an inter-specific soybean mapping population developed from a cross between Glycine max and Glycine soja.Results
Wild and cultivated soybean both contributed alleles towards significant additive large effect QTLs on chromosome 6 and 7 for a longer total root length and root distribution, respectively. Epistatic effect QTLs were also identified for taproot length, average diameter, and root distribution. These root traits will influence the water and nutrient uptake in soybean. Two cell division-related genes (D type cyclin and auxin efflux carrier protein) with insertion/deletion variations might contribute to the shorter root phenotypes observed in G. soja compared with cultivated soybean. Based on the location of the QTLs and sequence information from a second G. soja accession, three genes (slow anion channel associated 1 like, Auxin responsive NEDD8-activating complex and peroxidase), each with a non-synonymous single nucleotide polymorphism mutation were identified, which may also contribute to changes in root architecture in the cultivated soybean. In addition, Apoptosis inhibitor 5-like on chromosome 7 and slow anion channel associated 1-like on chromosome 15 had epistatic interactions for taproot length QTLs in soybean.Conclusion
Rare alleles from a G. soja accession are expected to enhance our understanding of the genetic components involved in root architecture traits, and could be combined to improve root system and drought adaptation in soybean.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1334-6) contains supplementary material, which is available to authorized users. 相似文献107.
Maria Braoudaki Fotini Tzortzatou-Stathopoulou Athanasios K. Anagnostopoulos Chrisa Papathanassiou Konstantinos Vougas Kalliopi Karamolegou George Th. Tsangaris 《Amino acids》2011,40(3):943-951
The aim of this study was to investigate the progression of myelodysplastic syndrome (MDS) to acute myeloid leukemia (AML)
and to provide additional data regarding the proteomic analysis of AML. The protein profiles obtained were correlated to cytogenetic
and molecular analyses. Bone marrow (BM) and peripheral blood (PB) samples were obtained during MDS diagnosis, at MDS transformation
to AML, at de novo AML diagnosis and 3 months following treatment. As controls, non-leukemic pediatric patients were studied.
Cytogenetic and molecular analyses were carried out by G banding and polymerase chain reaction followed by sequencing, respectively.
Differential proteomic analysis was performed by two-dimensional gel electrophoresis and protein identification by matrix-assisted
laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. No significant correlations were noted between protein
patterns and cytogenetic or molecular analyses. Certain suppressor genes, metabolic enzymes, immunoglobulins and actin-binding
proteins were differentially expressed by BM or PB plasma and cell lysates compared to controls. The obtained data showed
that vitamin D and gelsolin played contradicting roles in contributing and restraining leukemogenesis, while MOES, EZRI and
AIFM1 could be considered as biomarkers for AML. 相似文献
108.
Anna Makri Stamatia Bellou Maria Birkou Konstantinos Papatrehas Dimitrios Bokas Seraphim Papanikolaou George Aggelis 《Engineering in Life Science》2011,11(1):52-58
Tetraselmis sp. and Nannochloropsis oculata, cultivated in industrial‐scale bioreactors, produced 2.33 and 2.44% w/w lipid (calculated as the sum of fatty acid methyl esters) in dry biomass, respectively. These lipids contained higher amounts of neutral lipids and glycolipids plus sphingolipids, than phospholipids. Lipids of Tetraselmis sp. were characterized by the presence of eicosapentaenoic acid (that was located mainly in phospholipids), and octadecatetraenoic acid (that was equally distributed among lipid fractions), while these fatty acids were completely absent in N. oculata lipids. Additionally, lipids produced by 16 newly isolated strains from Greek aquatic environments (cultivated in flask reactors) were studied. The highest percentage of lipids was found in Prorocentrum triestinum (3.69% w/w) while the lowest in Prymnesium parvum (0.47% w/w). Several strains produced lipids rich in eicosapentaenoic and docosahexaenoic acids. For instance, docosahexaenoic acid was found in high percentages in lipids of Amphidinium sp. S1, P. parvum, Prorocentrum minimum and P. triestinum, while lipids produced by Asterionella sp. (?) S2 contained eicosapentaenoic acid in high concentration. These lipids, containing ω‐3‐long‐chain polyunsaturated fatty acids, have important applications in the food and pharmaceutical industries and in aquaculture. 相似文献
109.
Numerous alpine newt (Ichthyosaura alpestris) populations from the Balkans, representing all the previously established phylogeographic lineages, were studied for variations in various morphological characteristics (body size and shape, skull qualitative traits and number of trunk vertebrae). Here, we present a decoupling of morphological and mtDNA phylogeographic substructuring in the alpine newt on the Balkan Peninsula. In sharp contrast to other European newts (Triturus spp., Lissotriton spp.), the vast majority of morphological variation in the alpine newt is concentrated at the population level indicating an in situ morphological diversification. We found that the rate of morphological change is similar to the rate of mtDNA change. We hypothesize that the alpine newts are characterized by non-adaptive morphological evolution. 相似文献
110.
Pati A Gronow S Zeytun A Lapidus A Nolan M Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Detter JC Brambilla E Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lucas S 《Standards in genomic sciences》2011,4(1):45-53
Bacteroides helcogenes Benno et al. 1983 is of interest because of its isolated phylogenetic location and, although it has been found in pig feces and is known to be pathogenic for pigs, occurrence of this bacterium is rare and it does not cause significant damage in intensive animal husbandry. The genome of B. helcogenes P 36-108(T) is already the fifth completed and published type strain genome from the genus Bacteroides in the family Bacteroidaceae. The 3,998,906 bp long genome with its 3,353 protein-coding and 83 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献