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1.
Chelation therapy and supplemental Cr have both been shown to lead to improved blood glucose, lipids, and insulin activity.
Chelation therapy leads to the removal of toxic as well as essential metals. To determine if chelation therapy leads to increased
urinary Cr losses and altered Cr homeostasis, 2 groups of subjects (1 group that had undergone only 1 or no chelation therapy
and 1 group in which all subjects had undergone at least 19 chelation sessions) were evaluated for differences in possible
Cr homeostasis based on urinary Cr losses. There were no significant differences in urinary Cr losses between the two groups
of subjects and there were no significant increases in urinary Cr losses resulting from chelation therapy. Increases in urinary
Cr losses were strongly influenced by supplementation but not chelation therapy. 相似文献
2.
EDTA chelation effects on urinary losses of cadmium, calcium, chromium, cobalt, copper, lead, magnesium, and zinc 总被引:4,自引:0,他引:4
Robert S. Waters Noella A. Bryden Kristine Y. Patterson Claude Veillon Dr. Richard A. Anderson 《Biological trace element research》2001,83(3):207-221
The efficacy of a chelating agent in binding a given metal in a biological system depends on the binding constants of the chelator for the particular metals in the system, the concentration of the metals, and the presence and concentrations of other ligands competing for the metals in question. In this study, we make a comparison of the in vitro binding constants for the chelator, ethylenediaminetetraacetic acid, with the quantitative urinary excretion of the metals measured before and after EDTA infusion in 16 patients. There were significant increases in lead, zinc, cadmium, and calcium, and these increases roughly corresponded to the expected relative increases predicted by the EDTA-metal-binding constants as measured in vitro. There were no significant increases in urinary cobalt, chromium, or copper as a result of EDTA infusion. The actual increase in cobalt could be entirely attributed to the cobalt content of the cyanocobalamin that was added to the infusion. Although copper did increase in the post-EDTA specimens, the increase was not statistically significant. In the case of magnesium, there was a net retention of approximately 85% following chelation. These data demonstrate that EDTA chelation therapy results in significantly increased urinary losses of lead, zinc, cadmium, and calcium following EDTA chelation therapy. There were no significant changes in cobalt, chromium, or copper and a retention of magnesium. These effects are likely to have significant effects on nutrient concentrations and interactions and partially explain the clinical improvements seen in patients undergoing EDTA chelation therapy. 相似文献
3.
Alam Khan Noella A. Bryden Marilyn M. Polansky Richard A. Anderson 《Biological trace element research》1990,24(2-3):183-188
An unidentified factor that potentiates the action of insulin in glucose metabolism was investigated in selected foods and spices. Chromium content of these foods and spices was also determined. Foods and spices were extracted with 0.1N NH4OH (1∶20, w/v) and the supernatants assayed for insulin potentiation activity in the rat epididymal fat cell assay (see ref.6). Among the selected foods, tuna fish, peanut butter, and vanilla ice cream had some insulin potentiating activity. Among the spices, apple pie spice, cinnamon, cloves, bay leaves, and turmeric potentiated insulin activity more than three-fold. Chromium concentration of foods ranged from 1 to 145 ng/g, and spices ranged from 4 to 1818 ng/g. Insulin potentiating activity of foods and spices did not correlate with total chromium. Spices are generally used for flavor and taste in food preparations, but cinnamon, cloves, bay leaves, and turmeric may have an additional role in glucose metabolism. 相似文献
4.
Noella Silva-Martin María I. Daudén Sebastian Glatt Niklas A. Hoffmann Panagiotis Kastritis Peer Bork Martin Beck Christoph W. Müller 《PloS one》2016,11(1)
The Rvb1/Rvb2 complex is an essential component of many cellular pathways. The Rvb1/Rvb2 complex forms a dodecameric assembly where six copies of each subunit form two heterohexameric rings. However, due to conformational variability, the way the two rings pack together is still not fully understood. Here, we present the crystal structure and two cryo-electron microscopy reconstructions of the dodecameric, full-length Rvb1/Rvb2 complex, all showing that the interaction between the two heterohexameric rings is mediated through the Rvb1/Rvb2-specific domain II. Two conformations of the Rvb1/Rvb2 dodecamer are present in solution: a stretched conformation also present in the crystal, and a compact conformation. Novel asymmetric features observed in the reconstruction of the compact conformation provide additional insight into the plasticity of the Rvb1/Rvb2 complex. 相似文献
5.
Computerized video time lapse (CVTL) microscopy was used to observe cellular events induced by ionizing radiation (10-12 Gy) in nonclonogenic cells of the wild-type HCT116 colorectal carcinoma cell line and its three isogenic derivative lines in which p21 (CDKN1A), 14-3-3sigma or both checkpoint genes (double-knockout) had been knocked out. Cells that fused after mitosis or failed to complete mitosis were classified together as cells that underwent mitotic catastrophe. Seventeen percent of the wild-type cells and 34-47% of the knockout cells underwent mitotic catastrophe to enter generation 1 with a 4N content of DNA, i.e., the same DNA content as irradiated cells arrested in G(2) at the end of generation 0. Radiation caused a transient division delay in generation 0 before the cells divided or underwent mitotic catastrophe. Compared with the division delay for wild-type cells that express CDKN1A and 14-3-3sigma, knocking out CDKN1A reduced the delay the most for cells irradiated in G(1) (from approximately 15 h to approximately 3- 5 h), while knocking out 14-3-3sigma reduced the delay the most for cells irradiated in late S and G(2) (from approximately 18 h to approximately 3-4 h). However, 27% of wild-type cells and 17% of 14-3-3sigma(-/-) cells were arrested at 96 h in generation 0 compared with less than 1% for CDKN1A(-/-) and double-knockout cells. Thus expression of CDKN1A is necessary for the prolonged delay or arrest in generation 0. Furthermore, CDKN1A plays a crucial role in generation 1, greatly inhibiting progression into subsequent generations of both diploid cells and polyploid cells produced by mitotic catastrophe. Thus, in CDKN1A-deficient cell lines, a series of mitotic catastrophe events occurred to produce highly polyploid progeny during generations 3 and 4. Most importantly, the polyploid progeny produced by mitotic catastrophe events did not die sooner than the progeny of dividing cells. Death was identified as loss of cell movement, i.e. metabolic activity. Thus mitotic catastrophe itself is not a direct mode of death. Instead, apoptosis during interphase of both uninucleated and polyploid cells was the primary mode of death observed in the four cell types. Knocking out either CDKN1A or 14-3-3sigma increased the amount of cell death at 96 h, from 52% to approximately 70%, with an even greater increase to 90% when both genes were knocked out. Thus, in addition to effects of CDKN1A and 14-3-3sigma expression on transient cell cycle delay, CDKN1A has both an anti-proliferative and anti-apoptosis function, while 14-3-3sigma has only an anti-apoptosis function. Finally, the large alterations in the amounts of cell death did not correlate overall with the small alterations in clonogenic survival (dose-modifying ratios of 1.05-1.13); however, knocking out CDKN1A resulted in a decrease in arrested cells and an increase in survival, while knocking out 14-3-3sigma resulted in an increase in apoptosis and a decrease in survival. 相似文献
6.
María José López Furst Lautaro de Vedia Silvina Fernández Noella Gardella María Cristina Ganaha Sergio Prieto Edith Carbone Nicolás Lista Flavio Rotryng Graciana I. Morera Marta Mollerach Martín E. Stryjewski Grupo de Estudio de Infecciones de Piel y Estructuras Relacionadas por Staphylococcus aureus meticilino-resistente de la Comunidad Sociedad Argentina de Infectología 《PloS one》2013,8(11)
Background
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is now the most common cause of skin and skin structure infections (SSSI) in several world regions. In Argentina prospective, multicenter clinical studies have only been conducted in pediatric populations.Objective
Primary: describe the prevalence, clinical and demographic characteristics of adult patients with community acquired SSSI due to MRSA; secondary: molecular evaluation of CA-MRSA strains. Patients with MRSA were compared to those without MRSA.Materials and Methods
Prospective, observational, multicenter, epidemiologic study, with molecular analysis, conducted at 19 sites in Argentina (18 in Buenos Aires) between March 2010 and October 2011. Patients were included if they were ≥14 years, were diagnosed with SSSI, a culture was obtained, and there had no significant healthcare contact identified. A logistic regression model was used to identify factors associated with CA-MRSA. Pulse field types, SCCmec, and PVL status were also determined.Results
A total of 311 patients were included. CA-MRSA was isolated in 70% (218/311) of patients. Clinical variables independently associated with CA-MRSA were: presence of purulent lesion (OR 3.29; 95%CI 1.67, 6.49) and age <50 years (OR 2.39; 95%CI 1.22, 4.70). The vast majority of CA-MRSA strains causing SSSI carried PVL genes (95%) and were SCCmec type IV. The sequence type CA-MRSA ST30 spa t019 was the predominant clone.Conclusions
CA-MRSA is now the most common cause of SSSI in our adult patients without healthcare contact. ST30, SCCmec IV, PVL+, spa t019 is the predominant clone in Buenos Aires, Argentina. 相似文献7.
Noella Silva-Martín M. Gracia Retamosa Beatriz Maestro Sergio G. Bartual María J. Rodes Pedro García Jesús M. Sanz Juan A. Hermoso 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Streptococcus pneumoniae is a major pathogen responsible of important diseases worldwide such as pneumonia and meningitis. An increasing resistance level hampers the use of currently available antibiotics to treat pneumococcal diseases. Consequently, it is desirable to find new targets for the development of novel antimicrobial drugs to treat pneumococcal infections. Surface choline-binding proteins (CBPs) are essential in bacterial physiology and infectivity. In this sense, esters of bicyclic amines (EBAs) such as atropine and ipratropium have been previously described to act as choline analogs and effectively compete with teichoic acids on binding to CBPs, consequently preventing in vitro pneumococcal growth, altering cell morphology and reducing cell viability.Methods
With the aim of gaining a deeper insight into the structural determinants of the strong interaction between CBPs and EBAs, the three-dimensional structures of choline-binding protein F (CbpF), one of the most abundant proteins in the pneumococcal cell wall, complexed with atropine and ipratropium, have been obtained.Results
The choline analogs bound both to the carboxy-terminal module, involved in cell wall binding, and, unexpectedly, also to the amino-terminal module, that possesses a regulatory role in pneumococcal autolysis.Conclusions
Analysis of the complexes confirmed the importance of the tropic acid moiety of the EBAs on the strength of the binding, through π–π interactions with aromatic residues in the binding site.General significance
These results represent the first example describing the molecular basis of the inhibition of CBPs by EBA molecules and pave the way for the development of new generations of antipneumococcal drugs. 相似文献8.
Increased intake of chromium (Cr) often leads to improvements in glucose, insulin, lipids, and related variables in studies
involving humans and experimental and farm animals. However, the results are often variable, depending not only on the selection
of subjects but also dietary conditions and the form of supplemental Cr used. Our objective was to find a Cr supplement suitable
for humans that was absorbed better than any of those available. Chromium absorption by six adult subjects, three males and
three females, was determined based on the amount of Cr excreted in the urine in the initial 2 d following intake of 200 μg
of Cr of the various forms of chromium tested. The absorption of the newly synthesized complexes was greatest for those containing
histidine. Urinary Cr losses for six control subjects consuming 200 μg of Cr as Cr histidinate increased from basal levels
of 256±48 to 3670±338 ng/d compared with 2082±201 ng for Cr picolinate, the currently most popular nutrient supplement, in
the 48h following Cr consumption. Chromium histidinate complexes were stable and absorption was similar to the initial values
after more than 2 yr. Mixing of some of the complexes with starch, which was postulated to improve Cr absorption, was shown
to essentially block Cr absorption within 1 mo. These data demonstrate that urinary Cr losses need to be determined because
stability and absorption of the Cr complexes varies widely and could be responsible for the variability in some of the Cr
supplementation studies. Chromium ***DIRECT SUPPORT *** A02Q2015 00003 histidinate complexes are absorbed better than any
of the Cr complexes currently available and need to be evaluated as Cr nutritional supplements. 相似文献
9.
Thomas Bock Wei-Hua Chen Alessandro Ori Nayab Malik Noella Silva-Martin Jaime Huerta-Cepas Sean T. Powell Panagiotis L. Kastritis Georgy Smyshlyaev Ivana Vonkova Joanna Kirkpatrick Tobias Doerks Leo Nesme Jochen Ba?ler Martin Kos Ed Hurt Teresa Carlomagno Anne-Claude Gavin Orsolya Barabas Christoph W. Müller Vera van?Noort Martin Beck Peer Bork 《Nucleic acids research》2014,42(22):13525-13533
10.
Monjane AL Harkins GW Martin DP Lemey P Lefeuvre P Shepherd DN Oluwafemi S Simuyandi M Zinga I Komba EK Lakoutene DP Mandakombo N Mboukoulida J Semballa S Tagne A Tiendrébéogo F Erdmann JB van Antwerpen T Owor BE Flett B Ramusi M Windram OP Syed R Lett JM Briddon RW Markham PG Rybicki EP Varsani A 《Journal of virology》2011,85(18):9623-9636
Maize streak virus strain A (MSV-A), the causal agent of maize streak disease, is today one of the most serious biotic threats to African food security. Determining where MSV-A originated and how it spread transcontinentally could yield valuable insights into its historical emergence as a crop pathogen. Similarly, determining where the major extant MSV-A lineages arose could identify geographical hot spots of MSV evolution. Here, we use model-based phylogeographic analyses of 353 fully sequenced MSV-A isolates to reconstruct a plausible history of MSV-A movements over the past 150 years. We show that since the probable emergence of MSV-A in southern Africa around 1863, the virus spread transcontinentally at an average rate of 32.5 km/year (95% highest probability density interval, 15.6 to 51.6 km/year). Using distinctive patterns of nucleotide variation caused by 20 unique intra-MSV-A recombination events, we tentatively classified the MSV-A isolates into 24 easily discernible lineages. Despite many of these lineages displaying distinct geographical distributions, it is apparent that almost all have emerged within the past 4 decades from either southern or east-central Africa. Collectively, our results suggest that regular analysis of MSV-A genomes within these diversification hot spots could be used to monitor the emergence of future MSV-A lineages that could affect maize cultivation in Africa. 相似文献