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91.
Elizabeth Garcia Gustavo Aristizabal Catalina Vasquez Carlos E Rodriguez-Martinez Olga L Sarmiento Claudia L Satizabal 《Pediatric allergy and immunology》2008,19(4):307-314
This cross-sectional study of children aged 6-7 years and adolescents aged 13-14 years in Bogotá, Colombia, assessed the prevalence of asthma symptoms and their associations with dietary, health, and behavioral habits. This study is part of the International Study of Asthma and Allergies in Childhood (ISAAC)-phase III. Asthma prevalence among the children was assessed using a parental self-administered written questionnaire (WQ), and among adolescents using a WQ together with a video questionnaire (VQ). Associations were estimated with bivariate and multivariate analysis. The study found that the 6-7 year age-group were more likely to report current asthma symptoms than the 13-14 year age-group (10.4% [WQ] vs. 8.6% [WQ] and 8.0% [VQ], respectively). Factors associated with current asthma symptoms among the 6-7 year age-group included higher maternal education (OR = 1.7, [95% CI 1.2-2.6], p = 0.007), a cat in the home during the last year (OR = 1.5, [95% CI 1.0-2.3], p = 0.036), watching TV 1-2 hours/day (OR = 2.1, [95% CI 1.2-3.9], p = 0.013), and medication with acetaminophen in the first and most recent year of life (OR = 1.8, [95% CI 1.3-2.4], p < 0.001; OR = 2.2, [95% CI 1.7-2.8], p < 0.001, respectively) or antibiotics in the first year of life (OR = 1.9, [95% CI 1.4-2.5], p < 0.001). Among the 13-14 year age-group, factors associated with current asthma symptoms included medication with acetaminophen during the last year (OR = 1.8, [95% CI 1.4-2.3], p < 0.001); cereal, milk, and fruit consumption 3 or more times weekly (OR = 1.5, [95% CI 1.1-1.9], p = 0.010; OR = 0.8, [95% CI 0.6-1.0], p = 0.046; OR = 0.6, [95% CI 0.4-1.0], p = 0.031, respectively). Overall, compared with that in other Latin American centers, asthma prevalence in Bogotá is close the lower estimates. However, associations with dietary, health, and behavioral habits need further study to assess their complex relationship with asthma. 相似文献
92.
Petronila Penela Cristina Murga Catalina Ribas Vanesa Lafarga Federico Mayor Jr 《British journal of pharmacology》2010,160(4):821-832
GRK2 is a ubiquitous member of the G protein-coupled receptor kinase (GRK) family that appears to play a central, integrative role in signal transduction cascades. GRKs participate together with arrestins in the regulation of G protein-coupled receptors (GPCR), a family of hundreds of membrane proteins of key physiological and pharmacological importance, by triggering receptor desensitization from G proteins and GPCR internalization, and also by helping assemble macromolecular signalosomes in the receptor environment acting as agonist-regulated adaptor scaffolds, thus contributing to signal propagation. In addition, emerging evidence indicates that GRK2 can phosphorylate a growing number of non-GPCR substrates and associate with a variety of proteins related to signal transduction, thus suggesting that this kinase could also have diverse ‘effector’ functions. We discuss herein the increasing complexity of such GRK2 ‘interactome’, with emphasis on the recently reported roles of this kinase in cell migration and cell cycle progression and on the functional impact of the altered GRK2 levels observed in several relevant cardiovascular, inflammatory or tumour pathologies. Deciphering how the different networks of potential GRK2 functional interactions are orchestrated in a stimulus, cell type or context-specific way is critical to unveil the contribution of GRK2 to basic cellular processes, to understand how alterations in GRK2 levels or functionality may participate in the onset or development of several cardiovascular, tumour or inflammatory diseases, and to assess the feasibility of new therapeutic strategies based on the modulation of the activity, levels or specific interactions of GRK2. 相似文献
93.
Elizabeth Garcia Gustavo Aristizabal Catalina Vasquez Carlos E. Rodriguez-Martinez Olga L. Sarmiento Claudia L. Satizabal 《Pediatric allergy and immunology》2008,19(4):307-314
This cross‐sectional study of children aged 6–7 years and adolescents aged 13–14 years in Bogotá, Colombia, assessed the prevalence of asthma symptoms and their associations with dietary, health, and behavioral habits. This study is part of the International Study of Asthma and Allergies in Childhood (ISAAC)‐phase III. Asthma prevalence among the children was assessed using a parental self‐administered written questionnaire (WQ), and among adolescents using a WQ together with a video questionnaire (VQ). Associations were estimated with bivariate and multivariate analysis. The study found that the 6–7 year age‐group were more likely to report current asthma symptoms than the 13–14 year age‐group (10.4% [WQ] vs. 8.6% [WQ] and 8.0% [VQ], respectively). Factors associated with current asthma symptoms among the 6–7 year age‐group included higher maternal education (OR = 1.7, [95% CI 1.2–2.6], p = 0.007), a cat in the home during the last year (OR = 1.5, [95% CI 1.0–2.3], p = 0.036), watching TV 1–2 hours/day (OR = 2.1, [95% CI 1.2–3.9], p = 0.013), and medication with acetaminophen in the first and most recent year of life (OR = 1.8, [95% CI 1.3–2.4], p < 0.001; OR = 2.2, [95% CI 1.7–2.8], p < 0.001, respectively) or antibiotics in the first year of life (OR = 1.9, [95% CI 1.4–2.5], p < 0.001). Among the 13–14 year age‐group, factors associated with current asthma symptoms included medication with acetaminophen during the last year (OR = 1.8, [95% CI 1.4–2.3], p < 0.001); cereal, milk, and fruit consumption 3 or more times weekly (OR = 1.5, [95% CI 1.1–1.9], p = 0.010; OR = 0.8, [95% CI 0.6–1.0], p = 0.046; OR = 0.6, [95% CI 0.4–1.0], p = 0.031, respectively). Overall, compared with that in other Latin American centers, asthma prevalence in Bogotá is close the lower estimates. However, associations with dietary, health, and behavioral habits need further study to assess their complex relationship with asthma. 相似文献
94.
Puri Catalina Rosa Montes Gertru Ligero Laura Sanchez Teresa de la Cueva Clara Bueno Paola E Leone Pablo Menendez 《Molecular cancer》2008,7(1):76
Background
The use of human embryonic stem cells (hESCs) in research is increasing and hESCs hold the promise for many biological, clinical and toxicological studies. Human ESCs are expected to be chromosomally stable since karyotypic changes represent a pitfall for potential future applications. Recently, several studies have analysed the genomic stability of several hESC lines maintained after prolonged in vitro culture but controversial data has been reported. Here, we prompted to compare the chromosomal stability of three hESC lines maintained in the same laboratory using identical culture conditions and passaging methods. 相似文献95.
96.
Angel Josabad Alonso-Castro Candy Carranza-álvarez Ma Catalina Alfaro-De la Torre Leonardo Chávez-Guerrero Ramón Fernando García-De la Cruz 《Archives of environmental contamination and toxicology》2009,57(4):688-696
We investigated the effect of Cd and Pb on the growth of the aquatic macrophyte Typha latifolia; the removal from the solution and the accumulation of these elements by the plant were also studied. Thus, small plants
of T. latifolia, collected from a noncontaminated site, were exposed for 10 days to Cd and Pb, in a single solution or in mixture solutions,
at two concentrations of the metals (5 and 7.5 mg/L). Our results showed that T. latifolia removed effectively Cd and Pb from solutions and was able to accumulate these metals in the roots and, to a lesser extent,
in the leaves. Our findings suggested a synergistic effect of Cd and Pb with respect to the toxicity to T. latifolia. Additionally, Cd diminished the Pb absorption by T. latifolia. Our results confirmed, using scanning electron microscopy, the internalization of Cd and Pb in T. latifolia. 相似文献
97.
Catalina Isabel Villamil Alejandro Santiago-Nazario 《Anatomical record (Hoboken, N.J. : 2007)》2022,305(8):1974-1990
The nasopharynx is an important anatomical structure involved in respiration. Its bony boundaries, including the basicranium and upper cervical vertebrae, may be subject to selective pressures and constraints related to respiratory function. Here, we investigate phenotypic integration, or covariation, between the face, the basicranial boundaries of the nasopharynx, and the atlas and axis to understand constraints affecting these structures. We collected three-dimensional coordinate data from a sample of 80 humans and 44 chimpanzees, and used two-block partial least squares to assess RV (a multivariate generalization of Pearson's r2), rPLS, the covariance ratio, and effect size for integration among structures. We find that integration is significant among some of these structures, and that integration between the basicranial nasopharynx and vertebrae and between the face and vertebrae is likely independent. We also find divergences in the pattern of integration between humans and chimpanzees suggesting greater constraints among the human face and nasopharynx, which we suggest are linked to divergent developmental trajectories in the two taxa. Evolutionary changes in human basicranial anatomy, coupled with human-like developmental trajectories, may have required that the face grow to compensate any variation in nasopharyngeal structure. However, we were unable to determine whether the nasopharynx or the face is more strongly integrated with the vertebrae, and therefore whether respiration or biomechanical considerations related to positional behavior may be more strongly tied to vertebral evolution. Future work should focus on greater sample sizes, soft tissue structures, and more diverse taxa to further clarify these findings. 相似文献
98.
99.
Gfap‐positive radial glial cells are an essential progenitor population for later‐born neurons and glia in the zebrafish spinal cord
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Kimberly Johnson Cody J. Smith Chelsea Tyrrell Michael J. Parsons Rosemarie Doris Sarah Kucenas Gerald B. Downes Carla M. Velez Caitlin Schneider Catalina Sakai Narendra Pathak Katrina Anderson Rachael Stein Stephen H. Devoto Jeff S. Mumm Michael J. F. Barresi 《Glia》2016,64(7):1170-1189
Radial glial cells are presumptive neural stem cells (NSCs) in the developing nervous system. The direct requirement of radial glia for the generation of a diverse array of neuronal and glial subtypes, however, has not been tested. We employed two novel transgenic zebrafish lines and endogenous markers of NSCs and radial glia to show for the first time that radial glia are essential for neurogenesis during development. By using the gfap promoter to drive expression of nuclear localized mCherry we discerned two distinct radial glial‐derived cell types: a major nestin+/Sox2+ subtype with strong gfap promoter activity and a minor Sox2+ subtype lacking this activity. Fate mapping studies in this line indicate that gfap+ radial glia generate later‐born CoSA interneurons, secondary motorneurons, and oligodendroglia. In another transgenic line using the gfap promoter‐driven expression of the nitroreductase enzyme, we induced cell autonomous ablation of gfap+ radial glia and observed a reduction in their specific derived lineages, but not Blbp+ and Sox2+/gfap‐negative NSCs, which were retained and expanded at later larval stages. Moreover, we provide evidence supporting classical roles of radial glial in axon patterning, blood–brain barrier formation, and locomotion. Our results suggest that gfap+ radial glia represent the major NSC during late neurogenesis for specific lineages, and possess diverse roles to sustain the structure and function of the spinal cord. These new tools will both corroborate the predicted roles of astroglia and reveal novel roles related to development, physiology, and regeneration in the vertebrate nervous system. GLIA 2016;64:1170–1189 相似文献
100.
Jessica Brodt Greta Vladinov Catalina Castillo-Pedraza Lebron Cooper Edward Maratea 《Journal of clinical monitoring and computing》2016,30(5):649-653
Cerebral oxygen saturation (rSO2) is a non-invasive monitor used to monitor cerebral oxygen balance and perfusion. Decreases in rSO2 >20 % from baseline have been associated with cerebral ischemia and increased perioperative morbidity. During transcatheter aortic valve replacement (TAVR), hemodynamic manipulation with ventricular pacing up to 180 beats per minute is necessary for valve deployment. The magnitude and duration of rSO2 change during this manipulation is unclear. In this small case series, changes in rSO2 in patients undergoing TAVR are investigated. Ten ASA IV patients undergoing TAVR with general anesthesia at a university hospital were prospectively observed. Cerebral oximetry values were analyzed at four points: pre-procedure (baseline), after tracheal intubation, during valve deployment, and at procedure end. Baseline rSO2 values were 54.5 ± 6.9 %. After induction of general anesthesia, rSO2 increased to a mean of 66.0 ± 6.7 %. During valve deployment, the mean rSO2 decreased <20 % below baseline to 48.5 ± 13.4 %. In two patients, rSO2 decreased >20 % of baseline. Cerebral oxygenation returned to post-induction values in all patients 13 ± 10 min after valve deployment. At procedure end, the mean rSO2 was 67.6 ± 8.1 %. As expected, rapid ventricular pacing resulting in the desired decrease in cardiac output during valve deployment was associated with a significant decrease in rSO2 compared to post-induction values. However, despite increased post-induction values in all patients, whether related to increased inspired oxygen fraction or reduced cerebral oxygen consumption under anesthesia, two patients experienced a significant decrease in rSO2 compared to baseline. Recovery to baseline was not immediate, and took up to 20 min in three patients. Furthermore, baseline rSO2 in this population was at the lower limit of the published normal range. Significant cerebral desaturation during valve deployment may potentially be limited by maximizing rSO2 after anesthetic induction. Future studies should attempt to correlate recovery in rSO2 with recovery of hemodynamics and cardiac function, provide detailed neurological assessments pre and post procedure, determine the most effective method of maximizing rSO2 prior to hemodynamic manipulation, and provide the most rapid method of recovery of rSO2 following valve deployment. 相似文献