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71.
Wet tropical forest trees display a wide range of leaf phenology dynamics. However, the interrelation between deciduousness, water status, and leaf and stem characteristics have been poorly investigated compared with dry forests. We studied wet forest trees to answer the following questions: (1) do water regulation modes (iso/anisohydric behavior) of evergreen species differ from those found in deciduous species? (2) Does leaf water potential (ΨL) influences leaffall and emergence dynamics? (3) Are leaf and stem characteristics consistent across evergreen and deciduous trees? We evaluated vegetative phenology, ΨL, and leaf and stem characteristics of six evergreen and three deciduous species monthly for 2 yr. Species exhibited different leaffall and emergence dynamics, as well as different water regulation modes, independent of their deciduousness. Thus, the relationship between leaf phenology and water regulation behaviors appears to be a species‐specific property rather than a functional group attribute. ΨL had no direct influence on the dynamics of leaffall and/or emergence, indicating that this process is not modulated by water availability alone. Individual groups of evergreen and deciduous species could not be identified using principal component analysis (PCA), but a decoupling was observed in the leaf and stem economics spectra. The lack of an interrelation between deciduousness and iso/anisohydry, as well as the independence of leaf and stem trade‐offs, emphasizes that more systematic measurements of vegetative phenology and ecophysiological characteristics are necessary to advance our knowledge of leaf habit and water regulation behaviors based on the functional traits of wet forest plants.  相似文献   
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Amylin is a pancreatic hormone involved in the regulation of glucose metabolism and homeostasis. Restoration of the post-prandial and basal levels of human amylin in diabetic individuals is a key in controlling glycemia, controlling glucagon, reducing the insulin dose and increasing satiety, among other physiologic functions. Human amylin has a high propensity to aggregate. We have addressed this issue by designing a liposomal human amylin formulation. Nanoparticles of multilamellar liposomes comprising human amylin were obtained with 53% encapsulation efficiency. The in vitro kinetic release assay shows a biphasic profile. The stabilization of the lipidic nanoparticle against freeze-drying was achieved by using mannitol as a cryoprotectant, as evidenced by morphological characterization. The effectiveness of the human amylin entrapped in lipidic nanoparticles was tested by the measurement of its pharmacological effect in vivo after subcutaneous administration in mice. Collectively these results demonstrate the compatibility of human amylin with the lipidic interface as an effective pharmaceutical delivery system.  相似文献   
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Some lactic acid bacteria are capable of producing capsular or extracellular polysaccharides, with desirable technological properties and biological activities. Such polysaccharides produced by lactic acid bacteria are called exopolysaccharides and can be used to alter rheological properties, acting in processes involving viscosity, emulsification, and flocculation, among others. They may also be involved in prebiotic, probiotic, and biological activities, as well as having potential application in the food industry. In this mini-review, the objectives were to present some beneficial properties of exopolysaccharides (EPS) produced by Lactobacillus plantarum that have not been commercially explored. For that, the article focused to summarize revision of current publications within the following topics: (1) rheological properties, (2) prebiotic properties, (3) biological activities, and (4) potential application in the food industry. EPS produced by Lb. plantarum can be used as gelling agent, emulsifier, or stabilizer for food products. The glucan nature of the produced EPS enhances probiotic properties of this LAB species. Lactobacillus plantarum EPS has antioxidant, antibiofilm, and antitumor activities. Finally, there is an improvement in texture of fermented food products where Lb. plantarum is used as starter culture which is related to EPS production in situ. Therefore, EPS produced by Lb. plantarum have important and desirable properties to be explored for several applications, including health and food areas.  相似文献   
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Vilela  E. M.  Ladeiras-Lopes  R.  Ruivo  C.  Torres  S.  Braga  J.  Fonseca  M.  Ribeiro  J.  Primo  J.  Fontes-Carvalho  R.  Campos  L.  Miranda  F.  Nunes  J. P. L.  Gama  V.  Teixeira  M.  Braga  P. 《Netherlands heart journal》2019,27(7-8):347-353
Introduction

Exercise-based cardiac rehabilitation (EBCR) is part of the management of patients who have suffered an acute myocardial infarction (AMI). Patients with a reduced ejection fraction (EF) comprise a higher-risk subgroup and are referred less often for these programmes. This study aimed at assessing the impact of the baseline EF on the functional benefits, as assessed by peak oxygen uptake (pVO2) and exercise duration, of an EBCR programme in AMI survivors.

Methods

Observational, retrospective cohort study including all patients admitted to a tertiary centre due to an AMI who completed a phase II EBCR programme after discharge, between November 2012 and April 2017. Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test.

Results

A total of 379 patients were included [40.9% with reduced EF (<50%) at discharge]. After the programme, pVO2 and exercise duration increased significantly (p < 0.001). Patients with a reduced EF had a lower pVO2 and completed a shorter duration of exercise at the beginning and end of the programme. This group presented a higher increase in pVO2 (p = 0.001) and exercise duration (p = 0.007). This was maintained after adjusting for age, gender, history of coronary artery disease, number of sessions, Killip classification, arterial hypertension, dyslipidaemia, diabetes mellitus, smoking status and baseline pVO2.

Conclusion

A phase II EBCR programme was associated with significant improvements in pVO2 and exercise duration among AMI survivors, irrespective of baseline EF classification. Those with a reduced baseline EF derived an even greater improvement, highlighting the importance of EBCR in this subgroup of patients.

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Plasmonics - AgCl/CuO heterostructures were synthesized via a sonochemical method. AgCl/CuO molar compositions of 1:1 and 2:1 were prepared, respectively. Such compositions were prepared using...  相似文献   
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