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991.
Rubessa M Boccia L Campanile G Longobardi V Albarella S Tateo A Zicarelli L Gasparrini B 《Theriogenology》2011,76(7):1347-1355
The aim of this work was to evaluate whether minimizing the glucose concentration during culture or replacing the hexose with other energy substrates and/or embryotrophic compounds would affect the in vitro development, the resistance to cryopreservation and the sex ratio of bovine embryos. In vitro matured and fertilized oocytes were randomly assigned to 4 groups for in vitro culture, that differed in the energy substrates included: group A) 1.5 mM glucose, as in standard SOF; group B) 0.15 mM glucose; group C) 0.125 mM G3P, in the presence of 0.15 mM glucose and group D) 0.34 mM citrate, in combination with 2.77 mM myo-inositol. Blastocysts were evaluated on day 7, then vitrified by cryotop in 16.5% DMSO, 16.5% EG and 0.5 M sucrose and warmed in decreasing concentration of sucrose (0.25 to 0.15 M sucrose). The survival rates were assessed after 24 h in vitro culture. Finally, the blastocysts produced were sexed by PCR. An increased blastocyst rate was recorded in groups B, C and D, i.e., when glucose concentration was reduced, compared to group A (28.2, 41.0, 35.7 and 35.8, respectively in groups A, B, C and D; P < 0.01). However, the embryos cultured in group D showed the slowest developmental speed, indicated by the lowest percentage of advanced stage-embryos (expanded and hatched blastocysts) out of the total blastocysts (56.1, 45.8, 56.9 and 31.8 %, respectively in groups A, B, C and D; P < 0.01). Furthermore, survival rates after 24 h culture of vitrified-warmed blastocysts also decreased in group D (73.3, 73.1, 71.4 and 58.4%, respectively in groups A, B, C and D; P < 0.01). Interestingly, in group D a higher percentage of female embryos was obtained compared to group A, with intermediate values in groups B and C (45.6, 53.4, 50.0 and 61.5%, respectively in groups A, B, C and D; P < 0.05). In conclusion, it was demonstrated that the energy substrate during in vitro culture affects both the production and the viability of blastocysts. Furthermore, manipulating the metabolic profile of embryos during in vitro culture may have an impact on sex ratio. 相似文献
992.
Rafael Valim Reis Ana Paula Patrão Luis Borges Talita Perez Cantuaria Chierrito Eliezer Rodrigues de Souto Lauro Mera de Souza Marcello Iacomini Arildo José Braz de Oliveira Regina Aparecida Correia Gonçalves 《Plant Cell, Tissue and Organ Culture》2011,106(2):329-335
Cultures of adventitious roots of Stevia rebaudiana (Bert.) Bertoni were performed in a roller bottle system for the production of both primary and secondary metabolites. Adventitious
roots were induced from 1-cm-long root tip explants derived from in vitro regenerated plantlets on solid Murashige and Skoog
(MS 1962) media supplemented with 10.7 μM of α-naphthaleneacetic acid. These cultures were successfully maintained in the
same medium for 6 months with regular subcultures after 4 weeks. Thereafter, the roots were cut into 1.0- to 1.5-cm-long segments
and transferred to the roller bottle system containing a fresh root tissue culture on liquid MS medium supplemented with 10.7 μM
NAA. The apparatus consisted of a flask rolling system adjusted to 4g, and 3° of flask inclination. The roots were allowed to grow in the absence of light for adaptation and adventitious root
formation. The best conditions for cultivation were investigated, considering culture volume (25 ml), culture period (4 weeks),
salt concentrations in the nutrient medium (33%) and optimal initial inoculum (0.2 g) of S. rebaudiana roots. These results could give important information on how to improve the development of adventitious roots of S. rebaudiana for the production of primary and secondary metabolites. 相似文献
993.
994.
Carlo Alberto Scirè Maria Manara Marco Amedeo Cimmino Marcello Govoni Fausto Salaffi Leonardo Punzi Maria Cristina Monti Greta Carrara Carlomaurizio Montecucco Marco Matucci-Cerinic Giovanni Minisola 《Arthritis research & therapy》2013,15(5):R101
Introduction
Gout is the most prevalent arthritis and significantly impacts on function and quality of life. Given that gout associates with disabling comorbid conditions, it is not clear whether such a complex of diseases accounts for the increased disability or if gout may play a role by itself. This study aims to evaluate the specific influence of gout and disease-related features on functional disability and health-related quality of life (HRQoL) in patients with gout followed in rheumatology clinics.Methods
A random sample of patients was drawn from clinical registries of 30 rheumatology clinics across Italy. Sociodemographic, general health and gout-specific variables were collected. Functional disability and HRQoL were assessed by the health assessment questionnaire (HAQ) and the Physical and Mental Component Summary scores (PCS and MCS) of the Short Form-36 (SF-36). Crude and adjusted ordinal logistic and linear regression models were applied to investigate the specific contribution of different variables on HAQ and SF-36 scores. Results are presented as odds ratio (OR) or mean difference (MD) and 95% confidence intervals.Results
Out of 446 patients with gout, 90% were males with a mean age of 63.9 years and median disease duration of 3.8 years; the majority of patients were overweight or obese, and with several comorbidities; 21.1% showed at least moderate disability; the PCS score was significantly lower than expected age- and gender-matched samples in the general population, while MCS score was not. After adjusting for potential sociodemographic and general-health confounders, gout-specific variables significantly impacted on HAQ, including polyarticular involvement OR 3.82 (1.63, 8.95), presence of tophi OR 1.92 (1.07, 3.43) and recent attacks OR 2.20 (1.27, 3.81). Consistent results were found for PCS. The impairment of PCS compared to the general population was limited to patients with features of chronic gout. MCS was only affected by recent attacks (MD -2.72 [-4.58, -0.86]) and corticosteroid treatment (-3.39 [-5.30,-1.48]).Conclusions
The data from the KING study confirm that gout impacts on disability and provide evidence for an independent association of gout and gout-related features with functional outcome and HRQoL. This result supports the need to improve specific treatment in gout. 相似文献995.
Crivellente F Tontodonati M Fasdelli N Casartelli A Dorigatti R Faustinelli I Cristofori P 《Cell biology and toxicology》2011,27(6):425-438
The amino-terminal pro-brain natriuretic peptide (NT-proBNP) is released into the plasma predominantly from ventricular cardiomyocytes,
particularly in patients with chronic cardiac diseases, although small amounts are detectable in the plasma of healthy subjects.
While NT-proBNP has been widely exploited in human medicine, limited literature is available related to its characterization
in veterinary medicine (e.g., correlation with damage and specificity) and, particularly, in the context of preclinical drug
safety assessment. This paper describes the analytical performance characteristics and the biological variability of NT-proBNP
in male beagle dogs by using a commercially available enzyme-linked immunosorbent assay. Male beagle dogs were treated with
Casopitant, an NK1 receptor antagonist under development for depression and anxiety, which, when administered chronically
to dogs, caused cardiac toxicity. Heart weight increase, myocardial necrosis, degeneration, and inflammation associated with
high serum levels of cardiac troponin I characterized the end stage pathology observed in dogs treated orally at 40 mg/kg
for 39 weeks. Based on these data, ad hoc studies were designed in order to evaluate the possible relationship between NT-proBNP
serum levels and both standard toxicology endpoints, such as the organ weight and histology, as well as nonstandard endpoints
such as macroscopic morphometry and echocardiography. Early changes of NT-proBNP serum levels were observed following 2 weeks
of treatment onward, preceding most, if not all of the anatomical and functional changes. The results obtained demonstrate
that NT-proBNP acts as an early biomarker of cardiac changes, representing a sensitive and predictive marker of drug-induced
cardiac liability. 相似文献
996.
Burlini N Iriti M Daghetti A Faoro F Ruggiero A Bernasconi S 《Plant cell reports》2011,30(11):2131-2141
Benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), a particularly efficient inducer of systemic acquired resistance (SAR), was developed as an immunizing
agent to sensitize various crop species against pathogen infections. Recent works highlighted its activating effect on different
metabolic pathways, concerning both primary and secondary metabolites. In this study, we investigated the effect of BTH treatment
on sterol levels and vitamin D3 metabolism in Solanum malacoxylon cultures. Calli of S. malacoxylon were incubated in Gamborg B5 liquid medium alone or added with 50 μM BTH for different times (one, two or three cycles of
light). Histocytochemical investigations performed on our experimental system using 3,3′-diaminobenzidine (DAB) for hydrogen
peroxide (H2O2) detection and phloroglucinol for lignin staining showed that BTH causes H2O2 accumulation and lignin deposition in treated calli. Gas chromatographic analysis of principal cell membrane sterols (β-sitosterol,
campesterol, stigmasterol) showed that BTH transiently increases their cellular levels. Callus cultures were found to contain
also cholesterol, 7-dehydrocholesterol, the putative precursor of vitamin D3, and the hydroxylated metabolites 25-hydroxyvitamin D3 [25(OH)D3] and 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3]. BTH treatment enhanced 7-dehydrocholesterol while reduced cholesterol. HPLC analysis of sample extracts showed that BTH
does not affect the cell content of vitamin D3, though results of ELISA tests highlighted that this elicitor moderately enhances the levels of 25(OH)D3 and 1α,25(OH)2D3 metabolites. In conclusion, BTH treatment not only causes cell wall strengthening, a typical plant defence response, as just
described in other experimental models, but in the same time increases the cellular level of the main sterols and 7-dehydrocholesterol. 相似文献
997.
Luna-Vargas MP Christodoulou E Alfieri A van Dijk WJ Stadnik M Hibbert RG Sahtoe DD Clerici M Marco VD Littler D Celie PH Sixma TK Perrakis A 《Journal of structural biology》2011,175(2):113-119
High-throughput methods to produce a large number of soluble recombinant protein variants are particularly important in the process of determining the three-dimensional structure of proteins and their complexes. Here, we describe a collection of protein expression vectors for ligation-independent cloning, which allow co-expression strategies by implementing different affinity tags and antibiotic resistances. Since the same PCR product can be inserted in all but one of the vectors, this allows efficiency in versatility while screening for optimal expression strategies. We first demonstrate the use of these vectors for protein expression in Escherichia coli, on a set of proteins belonging to the ubiquitin specific protease (USP) Family. We have selected 35 USPs, created 145 different expression constructs into the pETNKI-His-3C-LIC-kan vector, and obtained 38 soluble recombinant proteins for 21 different USPs. Finally, we exemplify the use of our vectors for bacterial co-expression and for expression in insect cells, with USP4 and USP7 respectively. We conclude that our ligation-independent cloning strategy allows for high-throughput screening for the expression of soluble proteins in a variety of vectors in E. coli and in insect cells. In addition, the same vectors can be used for co-expression studies, at least for simple binary complexes. Application in the family of ubiquitin specific proteases led to a number of soluble USPs that are used for functional and crystallization studies. 相似文献
998.
Ballarin L Del Favero M Manni L 《Journal of experimental zoology. Part B. Molecular and developmental evolution》2011,316(4):284-295
Monoclonal antibodies were raised against hemocytes of the colonial ascidian Botryllus schlosseri as possible tools to study hemocyte differentiation. In this species, blood cells are involved in various biological functions, such as immunosurveillance, encapsulation of foreign bodies, metal accumulation, and allorecognition. The latter process drives the fusion or rejection of contacting colonies, according to whether they do or do not share at least one allele at the fusibility/histocompatibility (Fu/HC) locus. Hemocytes take part in the rejection reaction, which suggests that they express molecules, coded by the Fu/HC locus, on their surface. A homozygous colony at the Fu/HC locus was used to produce the antibodies, which were screened by immunocytochemistry on hemocyte monolayers, immunohistochemistry on colony paraffin sections, and immunoblotting on colony homogenates. Here, we report on one of the obtained antibodies (1D8), which recognized a surface epitope on hemocytes of the donor colony and other colonies, apparently in a manner specific to the Fu/HC genotype. It also labeled a single 80-kDa band in colony homogenates. In addition, it specifically recognized tunic cells, germ cells, and their accessory cells. These results strengthen the assumption of a close relationship among these types of cells and blood cells, and suggest a close relationship among the above cells, probably deriving from undifferentiated blood cells. 相似文献
999.
1000.
Nicola A. Colabufo Marialessandra Contino Mariangela Cantore Elena Capparelli Maria Grazia Perrone Giuseppe Cassano Giuseppe Gasparre Marcello Leopoldo Francesco Berardi Roberto Perrone 《Bioorganic & medicinal chemistry》2013,21(5):1324-1332
Substituted naphthalenyl derivatives bearing oxazole, or thiazole or furyl heteronuclei have been carried out as bioisosters of aryl-oxazoles and -thiazoles derivatives previously reported in order to investigate the role of the hindrance on the activity towards P-gp/BCRP/and MRP1 transporters. In addition, the role of naphthalenyl group to modulate P-gp intrinsic activity of these compounds was ascertained.The results demonstrated that all naphthalenyl derivatives displayed comparable P-gp activity with respect to lead compounds previously characterized in our SAR studies but were less active towards BCRP and MRP1 pumps. In terms of intrinsic activity, the replacement of aryl with naphthalenyl moiety led to P-gp inhibitors, unambiguous or ambiguous substrates on the base of the heteronucleus and the substituent on the naphthalenyl fragment. Indeed, oxazole derivatives were: inhibitors (R = H, F, OH), unambiguous substrates (R = OCH3), or ambiguous substrate (R = Br); thiazole derivatives were: unambiguous substrates (R = OCH3, Br), or ambiguous substrates (R = H, F). Finally furyl derivatives were ambiguous substrates. 相似文献