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Felipe S. Estrada Vito S. Hernandez Mauricio P. Medina Aleph A. Corona-Morales Oscar Gonzalez-Perez Arturo Vega-Gonzalez Limei Zhang 《Neuroscience letters》2009
2-Deoxy-d-glucose (2-DG) administration causes transient depletion of glucose derivates and ATP. Hence, it can be used in a model system to study the effects of a mild glycoprivic brain insult mimicking transient hypoglycemia, which often occurs when insulin or oral hypoglycemic agents are administered for diabetes control. In the present study, the effect of a single 2-DG application (500 mg/kg, a clinically applicable dose) on glial reactivity and neurogenesis in adult rat hippocampus was examined, as well as a possible temporal correlation between these two phenomena. Post-insult (PI) glial reactivity time course was assessed by immunoreaction against glial-fibrillary acidic protein (GFAP) during the following 5 consecutive days. A clear increase of GFAP immunoreactivity in hilus was observed from 48 to 96 h PI. Moreover, enhanced labeling of long radial processes in the granule cell layer adjacent to hilus was evidenced. On the other hand, a transient increase of progenitor cell proliferation was detected in the subgranular zone, prominently at 48 h PI, coinciding with the temporal peak of glial activation. This increase resulted in an augment of neuroblasts double labeled with 5-bromo-deoxyuridine (BrdU) and with double cortin (DCX) at day 7 PI. Around half of these cells survived 28 days showing matured neuronal phenotype double labeled by BrdU and a neuronal specific nuclear protein marker (NeuN). These findings suggest that a transient neuroglycoprivic state exerts a short-term effect on glial activation that possibly triggers a long-term effect on neurogenesis in hippocampus. 相似文献
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Lea A. Cupul-Uicab Beth C. Gladen Mauricio Hernández-Ávila Matthew P. Longnecker 《Maternal & child nutrition》2009,5(2):125-137
Breastfed children have lower risk of infectious diseases, post-neonatal mortality and chronic diseases later in life. Because epidemiologic studies usually rely on reported history of previous breastfeeding, data on the accuracy and precision of recalled histories allow improved interpretation of the epidemiologic findings.
We evaluated the reliability of two reported breastfeeding durations in 567 reproductive-aged women from Mexico using information obtained from nearly identical sets of questions applied at different times after weaning. We compared differences between reports, and examined the intraclass correlation coefficient (ICC) for any and for exclusive breastfeeding (EBF). Logistic regression was used to evaluate the determinants of poor recall (difference between reports of >20%).
The reliability of duration of any breastfeeding was high (ICC 0.94). Overall, differences between reports of duration were usually <1 month, and for 385/567, the difference was ≤0.5 months. Predictors of poorer recall were having ≥4 children, and time between reports of >2 months. The only predictor of better recall was greater age of the baby at weaning. The reliability of EBF duration was lower (ICC 0.49).
In this population with a relatively long duration of breastfeeding, reliability of any breastfeeding duration was high. Age, education and previous breastfeeding were not important predictors of recall, in contrast to findings in earlier studies. Consistent with previous reports, however, parity and length of recall were associated with poorer recall of duration of any breastfeeding. Future studies that use reported breastfeeding duration may want to consider the effect of these variables on recall. 相似文献
We evaluated the reliability of two reported breastfeeding durations in 567 reproductive-aged women from Mexico using information obtained from nearly identical sets of questions applied at different times after weaning. We compared differences between reports, and examined the intraclass correlation coefficient (ICC) for any and for exclusive breastfeeding (EBF). Logistic regression was used to evaluate the determinants of poor recall (difference between reports of >20%).
The reliability of duration of any breastfeeding was high (ICC 0.94). Overall, differences between reports of duration were usually <1 month, and for 385/567, the difference was ≤0.5 months. Predictors of poorer recall were having ≥4 children, and time between reports of >2 months. The only predictor of better recall was greater age of the baby at weaning. The reliability of EBF duration was lower (ICC 0.49).
In this population with a relatively long duration of breastfeeding, reliability of any breastfeeding duration was high. Age, education and previous breastfeeding were not important predictors of recall, in contrast to findings in earlier studies. Consistent with previous reports, however, parity and length of recall were associated with poorer recall of duration of any breastfeeding. Future studies that use reported breastfeeding duration may want to consider the effect of these variables on recall. 相似文献
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Aim: The objective of this experiment was to analyze processes involved in the incorporation of Bio‐Oss® Collagen in host tissue during healing following tooth extraction and grafting. Methods: Five beagle dogs were used. Four premolars in the mandible (3P3, 4P4) were hemi‐sected, the distal roots were removed and the fresh extraction socket filled with Bio‐Oss® Collagen. The mucosa was mobilized and the extraction site was closed with interrupted sutures. The tooth extraction and grafting procedures were scheduled in such a way that biopsies representing 1 and 3 days, as well as 1, 2 and 4 weeks of healing could be obtained. The dogs were euthanized and perfused with a fixative. Each experimental site, including the distal socket area, was dissected. The sites were decalcified in EDTA, and serial sections representing the central part of the socket were prepared in the mesio‐distal plane and parallel with the long axis of the extraction socket. Sections were stained in hematoxylin and eosin and were used for the overall characteristics of the tissues in the extraction socket. In specimens representing 1, 2 and 4 weeks of healing the various tissue elements were assessed using a morphometric point counting procedure. Tissue elements such as cells, fibers, vessels, leukocytes and mineralized bone were determined. In deparaffinized sections structures and cells positive for tartrate‐resistant acid phosphatase activity (TRAP), alkaline phosphatase and osteopontin were identified. Results: The biomaterial was first trapped in the fibrin network of the coagulum. Neutrophilic leukocytes [polymorphonuclear (PMN) cells] migrated to the surface of the foreign particles. In a second phase the PMN cells were replaced by multinuclear TRAP‐positive cells (osteoclasts). The osteoclasts apparently removed material from the surface of the xenogeneic graft. When after 1–2 weeks the osteoclasts disappeared from the Bio‐Oss® granules they were followed by osteoblasts that laid down bone mineral in the collagen bundles of the provisional matrix. In this third phase the Bio‐Oss® particles became osseointegrated. Conclusions: It was demonstrated that the incorporation of Bio‐Oss® in the tissue that formed in an extraction wound involved a series of different processes. To cite this article: Araújo MG, Liljenberg B, Lindhe J. Dynamics of Bio‐Oss® Collagen incorporation in fresh extraction wounds: an experimental study in the dog. Clin. Oral Impl. Res. 21 , 2010; 55–64. 相似文献
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Santiago Muñoz Fernández Pablo Lázaro y De Mercado Javier Alegre López Raquel Almodóvar González Alberto Alonso Ruiz Francisco Javier Ballina García Ana María Bilbao Cantarero Mercedes Cabañas Sáenz Rosario García-Vicuña Mauricio Mínguez Vega Isabel Padró Blanch José Andrés Román Ivorra Encarnación Roncal Marqueta 《Reumatología clinica》2013,9(4):206-215
BackgroundNursing clinics in rheumatology (NCR) are organizational models in the field of nursing care. There are various NCR models, but there is no consensus on its operational definition. Our objective is to develop quality standards to define and characterize a NCR.MethodTwo-round Delphi method. The panel consisted of 67 experts: Rheumatologists and nurses of the nursing working group of the Spanish Society of Rheumatology (SSR). The Delphi questionnaire was developed after a literature and experience review from previous SSR projects. The questionnaire consists of 7 sections: general considerations, standards of structure, process, treatment and monitoring, health education, training and research and quality of care. Each item was scored from 1 (least important) to 9 (most important) or by assigning a number (e.g., waiting days). The degree of agreement among the experts was categorized according to the coefficient of variation (CoV) between very high (CoV≤25%) and very low (CoV>100%).ResultsThe second round questionnaire (182 items) was answered by 46 panelists (34 rheumatologists and 12 nurses). A very important agreement was reached on the general standards of structure, process, treatment and monitoring, health education and quality of care. Less agreement was observed on standards related to training time, number of recommended nurses’ research projects and publications.ConclusionThe standards developed in this study would be useful for establishing desirable quality standards of structure and process, and criteria for clinical work, research and teaching that can be used to develop and evaluate the NCRs. 相似文献
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