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991.
Adela García‐Martín Alicia Acitores Marta Maycas María L. Villanueva‐Peñacarrillo Pedro Esbrit 《Journal of cellular biochemistry》2013,114(6):1404-1413
Parathyroid hormone‐related protein (PTHrP) stimulates osteoblastic function through its N‐ and C‐terminal domains. Since the osteogenic action of the latter domain appears to depend at least in part on its interaction with the vascular endothelial growth factor (VEGF) system, we aimed to explore the putative mechanism underlying this interaction in osteoblasts. Using native conditions for protein extraction and immunoblotting, we found that both PTHrP (107–139) and the shorter PTHrP (107–111) peptide (known as osteostatin), at 100 nM, promoted the appearance of a VEGF receptor (VEGFR) 2 protein band of apparent Mr. wt. 230 kDa, which likely represents its activation by dimer formation, in mouse osteoblastic MC3T3‐E1 cells. Moreover, osteostatin (100 nM) maximally increased VEGFR2 phosphorylation at Tyr‐1059 within 5–10 min in both MC3T3‐E1 and rat osteoblastic osteosarcoma UMR‐106 cells. This phosphorylation elicited by osteostatin appears to be VEGF‐independent, but prevented by the VEGFR2 activation inhibitor SU1498 and also by the Src kinase inhibitors SU6656 and PP1. Furthermore, osteostatin induced phosphorylation of Src, extracellular signal‐regulated kinase (ERK) and Akt with a similar time course to that observed for VEGFR2 activation in these osteoblastic cells. This osteostatin‐dependent induction of ERK and Akt activation was abrogated by SU6656. Up‐regulation of VEGF and osteoprotegerin gene expression as well as the pro‐survival effect induced by osteostatin treatment were all prevented by both SU1498 and SU6656 in these osteoblastic cells. Collectively, these findings demonstrate that the osteostatin domain of C‐terminal PTHrP phosphorylates VEGFR2 through Src activation, which represents a mechanism for modulating osteoblastic function. J. Cell. Biochem. 114: 1404–1413, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
992.
Juan José Ortiz Guzmán Arcos‐García José Luis Germán D. Mendoza Martínez Fernando Xicoténcatl Plata Pérez Gisela Fuentes Mascorro Gabriela Ruelas Inzunza 《Zoo biology》2013,32(3):277-280
The effects of the addition of lysine to commercial feed given to captive black iguana (Ctenosaura pectinata) were evaluated in terms of growth and feed digestibility. Twenty‐eight‐day‐old black iguana with an initial weight of 5.5 ± 0.3 g were housed individually in cages measuring 45 × 45 × 45 cm. The experiment lasted 150 days. The ambient temperature ranged from 28 to 35°C with a relative humidity of 60 to 95%. Treatments consisted of the addition of different percentages of lysine to the feed (0.0, 0.1, 0.2, and 0.3%, dry matter [DM] base). There was a linear response (P < 0.01) in daily gain (68, 112, 118, and 151 mg/d) and daily intake (251, 289, 297, and 337 mg/d) for levels from 0 to 0.3%, respectively, as well in the growth in head size, snout–vent length, and total length. The digestibility of DM, neutral detergent fiber, and acid detergent fiber were reduced linearly (P < 0.01) as lysine levels increased. Intake and digestibility were negatively correlated (r = –0.74; P < 0.001). It is concluded that the addition of lysine to the black iguana diet in the first months of life is important to stimulate growth and intake. Zoo Biol 32:277–280, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
993.
The following work provides basic information about the life history of 10 Cuban species of the family Poeciliidae. Adult fish stocks were captured in their natural habitat, and litters obtained from them were raised and maintained in captivity for 19 weeks. For each species, we present the mean value of newborn length (TLo), age at sexual maturity (AM), total length at sexual maturity (TLM), as well as the patterns of postnatal growth in aquarium conditions, which were described using size–age curves and nonlinear regression equations (Richards model). There are differences in growth dynamics among species. In general, growth rates differ for both sexes in all poeciliids studied, males maturing earlier than females, who reach higher values of total length at the 19th week (TLf). Sexual size dimorphism could be explained by the specific roles of each sex (fecundity in females and early maturity in males) while differences in growth among species could be related to their distribution patterns in the wild. The data summarized in this contribution can be useful for the conservation of these fish species. Zoo Biol 32:251–256, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
994.
Camila Mello dos Santos Aline Blaya Martins Renato José de Marchi Juliana Balbinot Hilgert Fernando Neves Hugo Dalva Maria Pereira Padilha 《Gerodontology》2013,30(3):176-186
doi: 10.1111/j.1741‐2358.2012.00656.x Assessing changes in oral health‐related quality of life and its factors in community‐dwelling older Brazilians Objective: To describe changes in oral health‐related quality of life and to evaluate the associations of these changes in community‐dwelling older people. Materials and methods: In this longitudinal study a representative sample of 872 older people, living in Brazil, was evaluated during 2004. The follow‐up was carried out during 2008, with 587 older persons evaluated. A questionnaire assessing socio‐demographic information, health history, oral health‐impact profile and number of natural teeth was used. Changes in oral health‐related quality of life were categorized as improvement or deterioration. Data analysis was performed using a hierarchical approach based in a conceptual framework. A hierarchal approach was carried out using Poisson regressions. Results: Older persons living in rural areas, those who reported brushing once a day or less and older persons with fewer natural teeth had an increased chance of reporting deterioration in oral health‐related quality of life. Women and participants who received a minimum wage of less than US$219.50 were more likely to report improvement in oral health‐related quality of life. Conclusion: The results of this study suggest that changes in the oral health‐related quality of life are influenced by many of the variables that were included in the conceptual framework. 相似文献
995.
996.
The entrainment limits to light‐dark cycles can be modified by the experimental conditions under which they are tested. Among the factors that may influence entrainment is the amount of wheel running exerted by the animal. In the present work, the effects of transitory and continuous wheel running on entrainment to light‐dark cycles were tested using a range of T cycles at the entrainment limits. Four groups of female hamsters were submitted to 1 h stepwise changes in T cycles. Two groups were exposed to T cycles of which the period was shortened at the lower limit from T22 to T18, and the other two groups were exposed to cycles that lengthened at the upper limit from T27 to T32. One of the groups at the lower limit and one at the upper limit had continuous access to a running wheel, while the others had the wheel locked, except at certain T when a lack of period control by T cycle appeared. The study demonstrates that access to running wheel widens the limits of entrainment to LD cycles. Specifically, the following observations were made: the effects of wheel running for entrainment were more evident in the groups with continuous access to wheel, as they did entrain to T19 and T32; continuous access to a wheel produced aftereffects only after T19, but not under T32; and when animals without a wheel showed relative coordination, unlocking the wheel favored entrainment in all the animals at T31, but in only 1 out 6 at T19. All of these indicate a different effect of the wheel running on the upper and lower limits of entrainment. 相似文献
997.
Ramón C. Hermida Diana E. Ayala Artemio Mojón Michael H. Smolensky José R. Fernández 《Chronobiology international》2013,30(11):1515-1527
ABSTRACTThe cost-effectiveness of ambulatory blood pressure (BP) monitoring (ABPM) versus traditional office BP measurement (OBPM) for the diagnosis and management of hypertension has been evaluated only by few studies and based solely on the reduction of medical care expenses through avoiding treatment of isolated-office hypertension. Data from the 21963 participants in the Hygia Project, a multicenter outcomes study that incorporates into routine primary care periodic, at least yearly, 48 h ABPM evaluation, were utilized to assess the cost-effectiveness – relative to vascular pathology expenditures countrywide in Spain – of ABPM versus OBPM. The actual reported Spanish healthcare expenditure for vascular pathology in 2015 – aggregate costs of medical examinations, outpatient and inpatient care, therapeutic interventions, plus non-healthcare services (productivity losses due to morbidity/mortality and informal family/friends-provided care) – was used to compare yearly costs when diagnostic and treatment decisions for hypertension are based on the OBPM versus the ABPM-model. Our economic analysis is based on the more realistic and feasible approach of restricting ABPM solely to high-risk individuals of age ≥60 years and/or with diabetes, chronic kidney disease, and/or previous cardiovascular event, who in the Hygia Project accounted for >90% of all documented events. The projected net benefit countrywide in favor of the proposed ABPM-model is ~5294M€/year, i.e., 360.33€/year (95%CI [347.52–374.85]) per ABPM-evaluated person. This highly conservative economic analysis indicates ABPM is a much more cost-effective strategy than repeated OBPM not only for accurate diagnosis and management of true hypertension but marked reduction of expenditures on elevated BP-associated vascular pathology. 相似文献
998.
Raquel López‐Antoñanzas Lawrence J. Flynn Fabien Knoll 《Cladistics : the international journal of the Willi Hennig Society》2013,29(3):247-273
The subfamily Rhizomyinae is known from the Late Oligocene up to the present. Today this group comprises six species, which live in southern Asia and eastern Africa. Despite the current moderate diversity of the rhizomyines, they had a greater diversification and wider distribution in the past: from Asia, their land of origin, to Africa, which they entered during the Early Miocene. So far 33 fossil species can be referred to this group. A cladistic analysis involving fossil and living species has been carried out. Prokanisamys spp. turned out to be the most basal taxa of the ingroup. This analysis calls into question the monophyly of several genera, and allows the proposal of a phylogenetic definition of the tribes Tachyoryctini and Rhizomyini. It also provides information about the origin of the African rhizomyines and allows inferring multiple dispersal phenomena from Asia to Africa in Early and Late Miocene times. 相似文献
999.
Boris L. Blotto José J. Nuñez Néstor G. Basso Carmen A. Úbeda Ward C. Wheeler Julián Faivovich 《Cladistics : the international journal of the Willi Hennig Society》2013,29(2):113-131
The frog clade composed of the alsodid genera Alsodes + Eupsophus is the most species‐rich of the Patagonian endemic frog clades, including nearly 31 of the slightly more than 50 species of that region. The biology of this group of frogs is poorly known, its taxonomy quite complex (particularly Alsodes), and its diversity in chromosome number striking when compared with other frogs (collectively, there are species having 2n = 22, 2n = 26, 2n = 28, 2n = 30 or 2n = 34). We present a phylogenetic analysis of this Patagonian frog clade based on mitochondrial and nuclear gene sequences. We sequenced five mitochondrial genes (cytochrome b, cytochrome oxidase I, 12S, 16S, NADH dehydrogenase subunit 1) with three intervening tRNAs, and fragments of three nuclear genes (seven in absentia homolog 1, rhodopsin exon 1, RAG‐1), for a maximum of 6510 bp for multiple specimens from 26 of the 31 species. We recovered Eupsophus as polyphyletic, with E. antartandicus, E. sylvaticus, and E. taeniatus in Batrachylidae, in accordance with most previous hypotheses. Based on this result, we transfer E. antartandicus and E. taeniatus back to Batrachyla, and E. sylvaticus to Hylorina (resurrected from the synonymy of Eupsophus), remediating the paraphyly of Eupsophus. Our results strongly corroborate the monophyly of Alsodes + Eupsophus (sensu stricto), the individual monophyly of these genera, and the monophyly of the species groups of Eupsophus. They also show the non‐monophyly of all non‐monotypic species groups of Alsodes proposed in the past. Our results expose several taxonomic problems particularly in Alsodes, and to a lesser extent in Eupsophus. This phylogenetic context suggests a rich evolutionary history of karyotypic diversification in the clade, in part corroborating previous hypotheses. In Alsodes, we predict three independent transformations of chromosome number from the plesiomorphic 2n = 26. All these, strikingly, involve increments or reductions of pairs of haploid chromosomes. Finally, the phylogenetic pattern recovered for Alsodes and Eupsophus suggests a trans‐Andean origin and diversification of the group, with multiple, independent ingressions over cis‐Andean regions. 相似文献
1000.
Yuri Wanderley Cavalcanti Daniel James Morse Wander José da Silva Altair Antoninha Del-Bel-Cury Xiaoqing Wei Melanie Wilson 《Biofouling》2013,29(1):27-38
This study examined the influence of bacteria on the virulence and pathogenicity of candidal biofilms. Mature biofilms (Candida albicans-only, bacteria-only, C. albicans with bacteria) were generated on acrylic and either analysed directly, or used to infect a reconstituted human oral epithelium (RHOE). Analyses included Candida hyphae enumeration and assessment of Candida virulence gene expression. Lactate dehydrogenase (LDH) activity and Candida tissue invasion following biofilm infection of the RHOE were also measured. Candida hyphae were more prevalent (p < 0.05) in acrylic biofilms also containing bacteria, with genes encoding secreted aspartyl-proteinases (SAP4/SAP6) and hyphal-wall protein (HWP1) up-regulated (p < 0.05). Candida adhesin genes (ALS3/EPA1), SAP6 and HWP1 were up-regulated in mixed-species biofilm infections of RHOE. Multi-species infections exhibited higher hyphal proportions (p < 0.05), up-regulation of IL-18, higher LDH activity and tissue invasion. As the presence of bacteria in acrylic biofilms promoted Candida virulence, consideration should be given to the bacterial component when managing denture biofilm associated candidoses. 相似文献