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1.
Nat Commun ; 13(1): 4945, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35999209

RESUMEN

Spatial arrangement of distinct Amazonian environments through time and its effect on specialized biota remain poorly known, fueling long-lasting debates about drivers of biotic diversification. We address the late Quaternary sediment deposition that assembled the world's largest seasonally flooded ecosystems. Genome sequencing was used to reconstruct the demographic history of bird species specialized in either early successional vegetation or mature floodplain forests. Sediment deposition that built seasonally flooded habitats accelerated throughout the Holocene (last 11,700 years) under sea level highstand and intensification of the South American Monsoon, at the same time as global increases in atmospheric methane concentration. Bird populations adapted to seasonally flooded habitats expanded due to enlargement of Amazonian river floodplains and archipelagos. Our findings suggest that the diversification of the biota specialized in seasonally flooded habitats is coupled to sedimentary budget changes of large rivers, which rely on combined effects of sea level and rainfall variations.


Asunto(s)
Ecosistema , Inundaciones , Animales , Aves , Bosques , Ríos
2.
Lab Anim ; 49(4): 327-35, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25673665

RESUMEN

Multiple-parametric small animal experiments require, by their very nature, a sufficient number of animals which may need to be large to obtain statistically significant results.(1) For this reason database-related systems are required to collect the experimental data as well as to support the later (re-) analysis of the information gained during the experiments. In particular, the monitoring of animal welfare is simplified by the inclusion of warning signals (for instance, loss in body weight >20%). Digital patient charts have been developed for human patients but are usually not able to fulfill the specific needs of animal experimentation. To address this problem a unique web-based monitoring system using standard MySQL, PHP, and nginx has been created. PHP was used to create the HTML-based user interface and outputs in a variety of proprietary file formats, namely portable document format (PDF) or spreadsheet files. This article demonstrates its fundamental features and the easy and secure access it offers to the data from any place using a web browser. This information will help other researchers create their own individual databases in a similar way. The use of QR-codes plays an important role for stress-free use of the database. We demonstrate a way to easily identify all animals and samples and data collected during the experiments. Specific ways to record animal irradiations and chemotherapy applications are shown. This new analysis tool allows the effective and detailed analysis of huge amounts of data collected through small animal experiments. It supports proper statistical evaluation of the data and provides excellent retrievable data storage.


Asunto(s)
Experimentación Animal , Animales de Laboratorio , Almacenamiento y Recuperación de la Información/métodos , Internet , Animales , Quimioterapia/instrumentación , Ratones , Ratones SCID , Radioterapia/instrumentación
3.
Int Endod J ; 47(9): 819-26, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24298904

RESUMEN

AIM: To evaluate the effects of two methods to simulate physiological pulpal pressure on the dentine bonding performance of two all-in-one adhesives and a two-step self-etch silorane-based adhesive by means of microtensile bond strength (µTBS) and nanoleakage surveys. METHODOLOGY: The self-etch adhesives [G-Bond Plus (GB), Adper Easy Bond (EB) and silorane adhesive (SIL)] were applied to flat deep dentine surfaces from extracted human molars. The restorations were constructed using resin composites Filtek Silorane or Filtek Z350 (3M ESPE). After 24 h using the two methods of simulated pulpal pressure or no pulpal pressure (control groups), the bonded teeth were cut into specimens and submitted to µTBS and silver uptake examination. Results were analysed with two-way anova and Tukey's test (P < 0.05). RESULTS: Both methods of simulated pulpal pressure led statistically similar µTBS for all adhesives. No difference between control and pulpal pressure groups was found for SIL and GB. EB led significant drop (P = 0.002) in bond strength under pulpal pressure. Silver impregnation was increased after both methods of simulated pulpal pressure for all adhesives, and it was similar between the simulated pulpal pressure methods. CONCLUSIONS: The innovative method to simulate pulpal pressure behaved similarly to the classic one and could be used as an alternative. The HEMA-free one-step and the two-step self-etch adhesives had acceptable resistance against pulpal pressure, unlike the HEMA-rich adhesive.


Asunto(s)
Grabado Ácido Dental , Adhesivos , Recubrimiento Dental Adhesivo , Cementos Dentales , Pulpa Dental/fisiología , Adolescente , Adulto , Humanos , Adulto Joven
4.
Res Exp Med (Berl) ; 180(1): 1-9, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7079591

RESUMEN

The effect of HSV (controls: sham), which induces hypergastrinemia, on duodenal Ca absorption was studied in "intact", TPTX, PTX, and TX rats. Ca absorption was estimated by an in vivo loop technique. As this technique increased serum gastrin by the duodenal Ca load, gastrin was also measured in rats not subjected to evaluation of Ca absorption. Following vagotomy gastrin rose significantly in "intact" as well as in TPTX, PTX, and TX rats. Further, intraduodenal Ca increased gastrin both after sham and vagotomy. However, gastrin in vagotomized rats was significantly higher than in sham rats, too. Although duodenal Ca absorption was not altered by vagotomy in "intact" and in TX rats, it was significantly lowered in vagotomized TPTX and PTX rats. Pretreatment of TPTX rats by pentagastrin for 10 days or immediately preceding experiments did not change Ca absorption. In addition, serum parathyroid hormone was unchanged by vagotomy in "intact" rats as compared to sham controls. We conclude that (1) vagotomy does not influence the rate of duodenal Ca absorption in "intact" rats, (2) Ca absorption is lower after vagotomy only in the absence of parathyroid glands, and (3) this vagotomy effect is not mimicked by exogenous pentagastrin and therefore appears unrelated to endogenous postvagotomy gastrinemia.


Asunto(s)
Calcio/metabolismo , Gastrinas/sangre , Absorción Intestinal , Animales , Duodeno/efectos de los fármacos , Duodeno/metabolismo , Absorción Intestinal/efectos de los fármacos , Masculino , Glándulas Paratiroides/fisiología , Hormona Paratiroidea/sangre , Pentagastrina/farmacología , Ratas , Ratas Endogámicas , Tiroidectomía , Vagotomía
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