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991.
Cooled-tip radiofrequencycatheter ablation of the cavotricuspid isthmus, performed after pulmonary vein isolation, resulted in acute occlusion of the posterolateral branch of the right coronary artery in a 49-year-old male with previously known right coronary artery disease. The occlusion was successfully stented. It is conceivable that previously diseased coronary arteries are more prone to be damaged during ablation. 相似文献
992.
Natalícia De Jesus Antunes Ricardo Carvalho Cavalli Maria Paula Marques Vera Lucia Lanchote 《Chirality》2013,25(1):1-7
Metoprolol is available for clinical use as a racemic mixture. The S‐(?)‐metoprolol enantiomer is the one expressing higher activity in the blockade of the β1‐adrenergic receptor. The α‐hydroxymetoprolol metabolite also has activity in the blockade of the β1‐adrenergic receptor. The present study describes the development and validation of a stereoselective method for sequential analysis of metoprolol and of α‐hydroxymetoprolol in plasma using high‐performance liquid chromatography with tandem mass spectrometry (LC‐MS/MS). 1‐ml aliquots of plasma were extracted with dichloromethane : diisopropyl ether (1:1, v/v). Metoprolol enantiomers and α‐hydroxymetoprolol isomers were separated on a Chiralpak AD column (Daicel Chemical Industries, New York, NY, USA) and quantitated by LC‐MS/MS. The limit of quantitation obtained was 0.2 ng of each metoprolol enantiomer/ml plasma and 0.1 ng/ml of each α‐hydroxymetoprolol isomer/ml plasma. The method was applied to the study of kinetic disposition of metoprolol in plasma samples collected up to 24 h after the administration of a single oral dose of 100‐mg metoprolol tartrate to a hypertensive parturient with a gestational age of 42 weeks. The clinical study showed that the metoprolol pharmakokinetics is enantioselective, with the observation of higher area under the curve (AUC)0?∞ values for S‐(?)‐metoprolol (AUCS‐(?)/AUCR‐(+) = 1.81) and the favoring of the formation of the new chiral center 1′R of α‐hydroxymetoprolol (AUC0?∞1′R/1′S = 2.78). Chirality, 25:1–7, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
993.
Daydreamer,a Ras effector and GSK-3 substrate,is important for directional sensing and cell motility
994.
Jimenez Eulalia Astbury Carol Albayaty Muna Whlby-Hamrn Ulrika Seoane Beatriz Villarroel Cristina Pujol Helena Bermejo Maria Jesus Aggarwal Ajay Psallidas Ioannis 《Respiratory research》2020,21(1):1-11
Nintedanib is an approved therapy for idiopathic pulmonary fibrosis (IPF). Some patients treated with nintedanib experience weight loss. Exploratory data suggest that low body mass index or weight loss are associated with worse outcomes in patients with IPF. We investigated whether BMI at baseline or weight loss over 52 weeks was associated with FVC decline, or influenced the effect of nintedanib, in patients with IPF. Using pooled data from the two INPULSIS trials, we analysed the rate of decline in FVC (mL/yr) over 52 weeks in patients treated with nintedanib and placebo in subgroups by baseline BMI (< 25; ≥25 to < 30; ≥30 kg/m2) and by weight loss over 52 weeks (≤5; > 5%) using random coefficient regression. In the placebo group, the mean rate of FVC decline over 52 weeks was numerically greater in patients with lower baseline BMI (− 283.3 [SE 22.4], − 207.9 [20.9] and − 104.5 [21.4] in patients with BMI < 25 kg/m2, ≥25 to < 30 kg/m2 and ≥ 30 kg/m2, respectively). Nintedanib reduced the rate of FVC decline versus placebo in all subgroups by BMI, with a consistent treatment effect across subgroups (interaction p = 0.31). In the placebo group, the mean rate of FVC decline was numerically greater in patients with > 5% than ≤5% weight loss over 52 weeks (− 312.7 [SE 32.2] versus − 199.5 [SE 14.4] mL/year). Nintedanib reduced the rate of FVC decline versus placebo in both subgroups by weight loss, with a greater treatment effect in patients with > 5% weight loss (interaction p = 0.0008). The adverse event profile of nintedanib was similar across subgroups. In patients with IPF, lower BMI and weight loss may be associated with faster decline in FVC. Nintedanib reduces the rate of FVC decline both in patients who lose weight on treatment and those who do not.
ClinicalTrials.gov
; Nos.
NCT01335464
and
NCT01335477
; URL:
www.clinicaltrials.gov
. 相似文献
995.
Carmen Fernandez-Becerra Joel Lelievre Mireia Ferrer Nuria Anton Richard Thomson Cristina Peligero Maria Jesus Almela Marcus VG Lacerda Esperanza Herreros Hernando A del Portillo 《Memórias do Instituto Oswaldo Cruz》2013,108(6):801-803
The production of fully functional human red cells in vitro from haematopoietic
stem cells (hHSCs) has been successfully achieved. Recently, the use of hHSCs
from cord blood represented a major improvement to develop the continuous
culture system for Plasmodium vivax. Here, we demonstrated that
CD34+hHSCs from peripheral blood and bone marrow can be expanded and
differentiated to reticulocytes using a novel stromal cell. Moreover, these
reticulocytes and mature red blood cells express surface markers for entrance of
malaria parasites contain adult haemoglobin and are also permissive to invasion
by P. vivax and Plasmodium falciparum
parasites. 相似文献
996.
Jesus Wong‐Muñoz Chris N. Anderson Roberto Munguía‐Steyer Alex Córdoba‐Aguilar 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(5):407-416
Copulation duration is often highly variable within and among species. Here, we explore the roles of body size, male morph, morph frequency, and alternative reproductive tactics to explain copulation duration in the damselfly Paraphlebia zoe. P. zoe has two male morphs (pigmented or hyaline wings) which differ in reproductive tactics (territorial or non‐territorial behaviors). We also analyze the effects of season as the frequencies of both morphs tend to vary along the reproductive season. In the first non‐experimental year, we found that the relationship between body size and copulation duration depended on the time of year. Early in the season, body size positively correlated with copulation duration, while late in the year, body size negatively correlated with copulation duration. In the second experimental year (when we reversed the frequency of male morphs in the middle of the season: making pigmented males less frequent than hyaline males), size influenced copulation duration as well as morph – body size positively correlated with copulation duration, and hyaline males mated for longer than pigmented males. Contrary to our prediction, changes to the relative abundances of morphs did not influence copulation duration. Hyaline males may be under selection for longer copulation durations to compensate for their reduced access to females, as long copulations potentially lead to more rival sperm to be removed from the female sperm storage organs and/or increased mate guarding. We do not discard, however, other explanations that drive variation in copulation duration such as cryptic female choice and/or predation. 相似文献
997.
Jia-Hsin Huang Jesus Lozano Xavier Belles 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Insect metamorphosis proceeds in two modes: hemimetaboly, gradual change along the life cycle; and holometaboly, abrupt change from larvae to adult mediated by a pupal stage. Both are regulated by 20-hydroxyecdysone (20E), which promotes molts, and juvenile hormone (JH), which represses adult morphogenesis. Expression of Broad-complex (BR-C) is induced by 20E and modulated by JH. In holometabolous species, like Drosophila melanogaster, BR-C expression is inhibited by JH in young larvae and enhanced in mature larvae, when JH declines and BR-C expression specifies the pupal stage.Methods
Using Blattella germanica as a basal hemimetabolous model, we determined the patterns of expression of BR-C mRNAs using quantitative RT-PCR, and we studied the functions of BR-C factors using RNA interference approaches.Results
We found that BR-C expression is enhanced by JH and correlates with JH hemolymph concentration. BR-C factors appear to be involved in cell division and wing pad growth, as well as wing vein patterning.Conclusions
In B. germanica, expression of BR-C is enhanced by JH, and BR-C factors appear to promote wing growth to reach the right size, form and patterning, which contrast with the endocrine regulation and complex functions observed in holometabolous species.General significance
Our results shed new light to the evolution from hemimetaboly to holometaboly regarding BR-C, whose regulation and functions were affected by two innovations: 1) a shift in JH action on BR-C expression during young stages, from stimulatory to inhibitory, and 2) an expansion of functions, from regulating wing development, to determining pupal morphogenesis. 相似文献998.
Gisele C. M. Dias Srgio R. Batlouni Mnica Cassel Chayrra Chehade Lzaro W. O. De Jesus Giovana S. Branco Marília P. Camargo Maria I. Borella 《Molecular reproduction and development》2020,87(7):783-799
The objective of this study was to establish a protocol for the characterization, isolation, and culture of type A spermatogonia using specific molecular markers for these cells in fish. To this end, adult Prochilodus lineatus testes were collected and digested enzymatically and the resulting testicular suspension was separated using a discontinuous Percoll gradient, followed by differential plating. The cell cultures obtained were monitored for 15 days and analyzed using the immunofluorescence method with anti‐Vasa, anti‐GFRα1, and anti‐OCT4 antibodies. Spermatogonial enrichment was also performed using flow cytometry. Although discontinuous Percoll gradient centrifugation followed by differential plating enabled the removal of differentiated germ cells and somatic cells, enriching the pool of type A spermatogonia, the enrichment of type A spermatogonia through flow cytometry of samples without Percoll proved to be more efficient. Prominent cell agglomerates that were characterized according to different stem cell markers as type A spermatogonia were observed during the 15 days of the cell culture. The use of immunoperoxidase and western blot analysis methods confirmed the specificity of the markers for type A spermatogonia of P. lineatus. When combined with specific cell culture conditions, the positive characterization of these molecular markers clarified certain aspects of spermatogonial regulation, such as survival and proliferation. Finally, understanding the regulation of the in vitro germ cell maintenance process may contribute to the enhancement of in vivo and in vitro reproduction techniques of endangered or aquaculture fish species. 相似文献
999.
Rita Scarpelli Julia K. Boueres Mauro Cerretani Federica Ferrigno Jesus M. Ontoria Michael Rowley Carsten Schultz-Fademrecht Carlo Toniatti Philip Jones 《Bioorganic & medicinal chemistry letters》2010,20(2):488-492
A potent series of substituted 2-phenyl-2H-indazole-7-carboxamides were synthesized and evaluated as inhibitors of poly (ADP-ribose) polymerase (PARP). This extensive SAR exploration culminated with the identification of substituted 5-fluoro-2-phenyl-2H-indazole-7-carboxamide analog 48 which displayed excellent PARP enzyme inhibition with IC50 = 4 nM, inhibited proliferation of cancer cell lines deficient in BRCA-1 with CC50 = 42 nM and showed encouraging pharmacokinetic properties in rats compared to the lead 6. 相似文献
1000.
Laiara Fernandes Rocha Rosileia Silva Souza Ana Lúcia Almeida Santana Diego Silva Macedo Ariadne Marques Silva Santana Roberta Carvalho da Silva Poliana Almeida Bezerra Ronival Dias Lima de Jesus Larissa Pires Barbosa 《Animal Reproduction》2021,18(2)
The objective of this study was to evaluate the testicular biometric, seminal, and plasma testosterone levels in lambs subjected to an anti-GnRH vaccine as a method of castration. Thirty entire, crossbred Santa Inês male lambs were randomly distributed into three treatment (T): T1 was the control group, with the administration of 1 mL of saline solution subcutaneously (SC); 1.0 and 0.5 mL of an anti-GnRH vaccine were administered SC in T2 and T3, respectively. Testicular biometric variables, physical and morphological variables of semen, and plasma testosterone concentrations were evaluated. At D60, there was a reduction in testicular length, width, thickness, and scrotal circumference of the immunocastrated animals regardless of the vaccine dose used (P < 0.05). A reduction in semen physical variables at both dosages (P < 0.05) was observed, with azoospermia, in 80% and 70% of animals in the T2 and T3 groups, respectively. At D60, the immunocastrated animals also showed an increase in spermatozoa defects (P < 0.05), whereas plasma testosterone concentration decreased (P < 0.05). Immunocastration of lambs using the Bopriva vaccine at doses of 1.0 and 0.5 mL is efficient in inducing azoospermia in up to 80% of animals, although two doses in a 30-day interval are necessary for it to be an effective and safe method. Efficacy was demonstrated through a reduction in serum testosterone levels, testicular biometry, and seminal fluid analysis. Considering the efficacy of both doses in this study, we recommend using the lower dose (0.5 mL), which will allow for a 50% reduction in vaccine costs. 相似文献