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11.
Frida E. Kleiman Raquel Dodelson de Kremer Ana Oller de Ramirez Roy A. Gravel Carlos E. Argaraña 《Human genetics》1994,94(3):279-282
The level of -hexosaminidase activity in plasma and leukocytes and the frequency of three known HEXB mutations were studied in an Argentinean deme with high incidence of infantile Sandhoff disease. Two mutations were previously identified in one of two Sandhoff patients from the region, a splice mutation, IVS-2+1 GA, and a 4-bp deletion, CTTT782–785. These mutations, and a 16kb deletion from the 5' end of the HEXB gene common in non-Argentineans, were screened in 9 Sandhoff patients (all unrelated), 24 obligate heterozygotes, 33 additional individuals belonging to families with affected members, and 64 randomly ascertained individuals from the high risk region. Of 31 independent alleles examined, including those of the two patients previously reported, 30 had the IVS-2 splice mutation and only the originally reported patient had the CTTT deletion. The 16-kb deletion was not observed. Further, among the 57 unaffected members of families with a previous history of Sandhoff disease, and absolute correlation was found between carrier diagnosis by enzyme assay of leukocytes and the DNA-based tests for mutation. One of the 64 controls was classified as a carrier by enzyme assay but did not have one of the three mutations screened. We conclude that a single mutation predominates in this Argentinean population and that the DNA-based test can be an effective supplement or alternative to enzyme-based testing. 相似文献
12.
J. L. Albi J. Planas J. Sánchez 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1993,163(2):118-122
Glucose metabolism in peripheral blood lymphocytes from the brown trout Salmo trutta has been studied. Glucose is taken up by means of a sodium-independent saturable process (K
m=10.8 mmol·l-1), as well as by simple diffusion. Once within the cell, most of glucose is directed to lactate production through either the Embden-Meyerhof pathway or the hexose-monophosphate shunt. Rates of lactate formation are higher than rates of CO2 formation. Glutamine does not exert an effect on either glucose uptake or glucose metabolism. The present study provides information regarding the nature of energy sources for different cell types in salmonids.Abbreviations 3-OMG
3-O-methyl glucose
- EM
Embden-Meyerhoff pathway
- G6D
glucose-6-phosphate dehydrogenase
- HK
hexokinase
- HMS
hexose monophosphate shunt
- ICDH
isocitrate dehydrogenase
-
K
m
apparent Michaelis constant
- LDH
lactate dehydrogenase
- MCB
modified Cortland buffer
- PBL
peripheral blood lymphocytes
- PFK
fructose-6-phosphate kinase
- PK
pyruvate kinase
- RBC
red blood cells
-
V
max
maximal rate of uptake 相似文献
13.
14.
Yadira Rodríguez Silvia García Raquel Lebrero Raúl Muñoz 《Biotechnology and bioengineering》2023,120(11):3224-3233
Biogas biorefineries have opened up new horizons beyond heat and electricity production in the anaerobic digestion sector. Added-value products such as polyhydroxyalkanoates (PHAs), which are environmentally benign and potential candidates to replace conventional plastics, can be generated from biogas. This work investigated the potential of an innovative two-stage growth-accumulation system for the continuous production of biogas-based polyhydroxybutyrate (PHB) using Methylocystis hirsuta CSC1 as cell factory. The system comprised two turbulent bioreactors in series to enhance methane and oxygen mass transfer: a continuous stirred tank reactor (CSTR) and a bubble column bioreactor (BCB) with internal gas recirculation. The CSTR was devoted to methanotrophic growth under nitrogen balanced growth conditions and the BCB targeted PHB production under nitrogen limiting conditions. Two different operational approaches under different nitrogen loading rates and dilution rates were investigated. A balanced nitrogen loading rate along with a dilution rate (D) of 0.3 day−1 resulted in the most stable operating conditions and a PHB productivity of ~53 g PHB m−3 day−1. However, higher PHB productivities (~127 g PHB m−3 day−1) were achieved using nitrogen excess at a D = 0.2 day−1. Overall, the high PHB contents (up to 48% w/w) obtained in the CSTR under theoretically nutrient balanced conditions and the poor process stability challenged the hypothetical advantages conferred by multistage vs single-stage process configurations for long-term PHB production. 相似文献
15.
Luisa F. Gómez-Correa Camila Jaramillo-Hernández Alvaro Duque Raquel Fernandes Araujo Gabriel Arellano Stuart J. Davies Nicolas Castaño Jörg Haarpaintner Fabian Enßle Daniel Zuleta 《Biotropica》2023,55(6):1136-1147
Understanding what drives changes in tree mortality as well as the covariates influencing trees' response is a research priority to predict forest responses to global change. Here, we combined drone photogrammetry and ground-based data to assess the influence of crown exposure to light (relative to total crown area), growth deviations (relative to conspecifics), tree size, and species' wood density (as a surrogate for light-demanding and shade-tolerant life-history strategies) on the mortality of 984 canopy trees in an Amazon terra firme forest. Trees with lower wood density were less prone to die when their proportion of crown was more exposed to sunlight, but this relationship with relative crown exposure weakened and slightly reversed as wood density increased. Trees growing less than their species average had higher mortality, especially when the species' wood density decreased. The role of wood density in determining the survival of canopy trees under varying light conditions indicates differential responses of light-demanding versus shade-tolerant species. Our results highlight the importance of accounting for life-history strategies, via plant functional types, in vegetation dynamic models aiming to predict forest demography under a rapidly changing climate. Abstract in Spanish is available with online material. 相似文献
16.
Marden A. de Alvarenga Raimundo Braz Fo Otto R. Gottlieb João P. de P. Dias Aderbal F. Magalhães Eva G. Magalhães Gouvan C. de Magalhães Mauro T. Magalhães José G.S. Maia Raquel Marques Anita J. Marsaioli Antônio A.L. Mesquita Anselmo A. de Moraes Alaide B. de Oliveira Geovane G. de Oliveira Gentil Pedreira Sebastião K. Pereira Sonildes L.V. Pinho Celira C. Santos 《Phytochemistry》1978,17(3):511-516
Wood samples, infested by fungi during storage, were shown to contain, besides the known 5-methyl-mellein, additional (3R)-8-hydroxy-3-methyl-3,4-dihydroisocoumarins substituted by 7-methyl, 5-formyl, 5-carboxy, 5-hydroxy, 5-methoxy, 6-methoxy-5-methyl and 6,7-dimethoxy-5-methyl groups, as well as 6-formyl-7-hydroxy-5-methoxy-4-methylphthalide. Several 2-methylchromanones were synthesized in order to show that this class of compounds can be distinguished from 3-methyl-3,4-dihydroisocoumarins by MS. 相似文献
17.
John E. Byfield Raquel Zerubavel Eric W. Fonkalsrud 《Cancer immunology, immunotherapy : CII》1982,14(2):117-123
Summary The in vitro and in vivo activity has been investigated of antisera prepared against a murine (C-1300) neuroblastoma line (MNB) capable of differentiation. An antibody-dependent cellular cytotoxicity (ADCC) reaction was employed using rat spleen cells (RSC). ADCC activity in vitro (using 51Cr-release) was shown, but a maximum of only 50% of the immunologically releasable 51Cr was achieved. Nevertheless, in vivo (syngeneic mouse-tumor flank assay) significant delays were obtained in tumor onset and lethality. Under ideal circumstances, i.e., coating of tumor cells prior to inoculation and high RSC effector cell ratios, a significant number of animals could be cured of substantial tumor burdens (106 cells). While close proximity of the site of injection of effector cells was required (ectopic injections of RSC were ineffective), the anti-MNB ADCC was shown to be quite active in vivo without external precoating of the cells with antisera. RCS obtained from BCG-treated rats were more numerous and slightly more effective. RSC obtained from -radiated animals retained normal activity. With appropriate antisera this approach could be useful under selected clinical circumstances. 相似文献
18.
Raquel Santos Jorge Troy R. Hawkins Edgar G. Hertwich 《The International Journal of Life Cycle Assessment》2012,17(1):9-15
Purpose
The purpose of this study is to provide life cycle inventory data and results for components of electrical grids to the larger community of life cycle assessment practitioners. This article is the first in a series of two, each focusing on different components of power grids. In part 1, the objects under scope are power lines and cables. Systems for overhead, underground, and subsea transmission are modeled here, including HVDC systems used in long-distance transmission. 相似文献19.
A. Planas M. Juncosa A. Cayetano E. Querol 《Applied microbiology and biotechnology》1992,37(5):583-589
Summary A new purification procedure for endo-\-1,3-1,4-d-glucanase from Bacillus licheniformis is described. The secreted enzyme was purified both from B. licheniformis and from recombinant Escherichia coli harbouring the cloned gene by ion exchange chromatography on a CM-Sepharose matrix at pH 5.6. The mature enzyme was resistant to proteolysis by trypsin and chymotrypsin but it was slowly digested by protease V8. It showed a continuous trimming where no large-limit polypeptides were noticeable thus supporting a monodomain structure. Former appearing peptides have been assigned theoretically according to the protein sequence and predictive methods of accessible areas. Kinetic parameters for the hydrolysis of barley \-glucan and lichenan by measuring the net release of reducing sugars at the optimum pH (7.02) and temperature (55° C) are k
cat=3500 ±800 s–1 (turnover number) and K
m=1.45±0.21 mg/ml for barley \-glucan and k
cat=3000±750 s–1 and K
m=1.98±0.40 mg/ml for lichenan.
Correspondence to: E. Querol 相似文献
20.
Willig Julia Biz Vianna Débora Renz Barreto Beckenkamp Aline Beckenkamp Liziane Raquel Sévigny Jean Wink Márcia Rosângela Buffon Andréia Pilger Diogo André 《Purinergic signalling》2020,16(1):29-40
Purinergic Signalling - Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the occurrence of the t(9;22)(q34;q11) translocation. First-line therapy for CML consists... 相似文献