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991.
Smoothened‐antagonists reverse homogentisic acid‐induced alterations of Hedgehog signaling and primary cilium length in alkaptonuria 下载免费PDF全文
992.
Annalisa Bruno Daniele Cortecchia Xin Yu Chin Kunwu Fu Pablo P. Boix Subodh Mhaisalkar Cesare Soci 《Liver Transplantation》2017,7(18)
Despite their excellent power conversion efficiency, MAPbI3 solar cells exhibit strong hysteresis that hinders reliable device operation. Herein it is shown that ionic motion is the dominant mechanism underlying hysteresis of MAPbI3 solar cells by studying the effects of electrical poling in different temperature ranges. Complete suppression of the hysteresis below 170 K is consistent with temperature activated diffusion of I? anions and/or the motion of the MA+ cations. Ionic motion has important effect on the overall efficiency of the MAPbI3 solar cells: the initial decrease of the power conversion efficiency while lowering the operating temperature is recovered and even enhanced up to 20% of its original value by applying an electrical poling. The open circuit voltage significantly increases and the current density fully recovers due to the reduction of the electron extraction barrier at the TiO2/MAPbI3 interface driven by the charge accumulation at the interface. Moreover, beside TiO2/MAPbI3 interfacial charge transfer, charge transport in TiO2 strongly affects the photovoltaic performance, as revealed by MAPbI3/ms‐TiO2 field effect transistors. These results establish the basis to develop effective strategies to mitigate operational instability of perovskites solar cells. 相似文献
993.
994.
Liliana Fajardo-Mellor Annalisa Berta Robert L. Brownell Jr †. Claudia C. Boy ‡R. Natalie P. Goodall ‡ 《Marine Mammal Science》2006,22(4):910-932
Prior studies of phylogenetic relationships among phocoenids based on morphology and molecular sequence data conflict and yield unresolved relationships among species. This study evaluates a comprehensive set of cranial, postcranial, and soft anatomical characters to infer interrelationships among extant species and several well-known fossil phocoenids, using two different methods to analyze polymorphic data: polymorphic coding and frequency step matrix. Our phylogenetic results confirmed phocoenid monophyly. The division of Phocoenidae into two subfamilies previously proposed was rejected, as well as the alliance of the two extinct genera Salumiphocaena and Piscolithax with Phocoena dioptrica and Phocoenoides dalli . Extinct phocoenids are basal to all extant species. We also examined the origin and distribution of porpoises within the context of this phylogenetic framework. Phocoenid phylogeny together with available geologic evidence suggests that the early history of phocoenids was centered in the North Pacific during the middle Miocene, with subsequent dispersal into the southern hemisphere in the middle Pliocene. A cooling period in the Pleistocene allowed dispersal of the southern ancestor of Phocoena sinus into the North Pacific (Gulf of California). 相似文献
995.
Romualdo Caputo Annalisa Guaragna Giovanni Palumbo Silvana Pedatella 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):651-652
Abstract 2-[[O-(p-Methoxybenzyl)-oxy]methyl]-5,6-dihydro-1,4-dithiin 1 is a versatile three carbon homologation reagent which has been conveniently used in the synthesis of enantiomerically pure modified nucleosides. 相似文献
996.
Mariangela Rondanelli Annalisa Opizzi Simone Perna Milena Anna Faliva 《Endocrinología y nutrición》2013,60(4):197-210
Osteoporosis is a leading cause of morbidity and mortality in the elderly and influences quality of life, as well as life expectancy. Currently, there is a growing interest among the medical scientists in search of specific nutrients and/or bioactive compounds of natural origin for the prevention of disease and maintenance of bone health. Although calcium and vitamin D have been the primary focus of nutritional prevention of osteoporosis, a recent research has clarified the importance of several additional nutrients and food constituents. Based on this review of the literature, supplementation with vitamins B, C, K, and silicon could be recommended for proper maintenance of bone health, although further clinical studies are needed. The results of studies on long-chain polyunsaturated fatty acids, potassium, magnesium, copper, selenium, and strontium are not conclusive, although studies in vitro and in animal models are interesting and promising. 相似文献
997.
Patrizia Garbati Annalisa Salis Enrico Adriano Andrea Galatini Gianluca Damonte Maurizio Balestrino Enrico Millo 《Amino acids》2013,45(4):821-833
Creatine is an amino acid that has a pivotal role in energy metabolism of cells. Creatine acts as an “ATP shuttle”, carrying ATP to the sites where it is utilized, through its reversible phosphorylation by creatine kinase. Moreover, the creatine-phosphocreatine system delays ATP depletion during anoxia or ischemia, thus exerting a neuroprotective role during those pathological conditions. Thus, its administration has been advocated as a treatment or prevention of several conditions involving the central nervous system. However, creatine crosses poorly the blood–brain barrier and the cell plasma membrane, thus its administration has but a limited effect. The use of more lipophilic creatine derivatives has thus been suggested. However, such a synthesis is complicated by the intrinsic characteristics of the creatine molecule that hardly reacts with other molecules and easily cyclizes to creatinine. We obtained amide derivatives from creatine starting from a new protected creatine molecule synthesized by us, the so-called (Boc)2-creatine. We used a temporary protection only on the creatine guanidine group while allowing a good reactivity on the carboxylic group. This temporary protection ensured efficient creatine dissolution in organic solvents and offered simultaneous protection of creatine toward intramolecular cyclization to creatinine. In this manner, it was possible to selectively conjugate molecules on the carboxylic group. The creatine guanidine group was easily released from the protection at the end of the reaction, thus obtaining the desired creatine derivative. 相似文献
998.
The highest density of glutamate transporters in the brain is found in astrocytes. Glutamate transporters couple the movement of glutamate across the membrane with the co-transport of 3 Na+ and 1 H+ and the counter-transport of 1 K+. The stoichiometric current generated by the transport process can be monitored with whole-cell patch-clamp recordings from astrocytes. The time course of the recorded current is shaped by the time course of the glutamate concentration profile to which astrocytes are exposed, the kinetics of glutamate transporters, and the passive electrotonic properties of astrocytic membranes. Here we describe the experimental and analytical methods that can be used to record glutamate transporter currents in astrocytes and isolate the time course of glutamate clearance from all other factors that shape the waveform of astrocytic transporter currents. The methods described here can be used to estimate the lifetime of flash-uncaged and synaptically-released glutamate at astrocytic membranes in any region of the central nervous system during health and disease. 相似文献
999.
Roberto?Berni?CananiEmail author Gianluca?Terrin Ausilia?Elce Vincenza?Pezzella Peter?Heinz-Erian Annalisa?Pedrolli Chiara?Centenari Felice?Amato Rossella?Tomaiuolo Antonio?Calignano Riccardo?Troncone Giuseppe?Castaldo 《Orphanet journal of rare diseases》2013,8(1):194
Background
Congenital chloride diarrhea (CLD) is an autosomal recessive disorder characterized by life-long, severe diarrhea with intestinal Cl- malabsorption. It results from a reduced activity of the down regulated in adenoma exchanger (DRA), due to mutations in the solute carrier family 26, member 3 (SLC26A3) gene. Currently available therapies are not able to limit the severity of diarrhea in CLD. Conflicting results have been reported on the therapeutic efficacy of oral butyrate.Methods
We investigated the effect of oral butyrate (100 mg/kg/day) in seven CLD children with different SLC26A3 genotypes. Nasal epithelial cells were obtained to assess the effect of butyrate on the expression of the two main Cl- transporters: DRA and putative anion transporter-1 (PAT-1).Results
A variable clinical response to butyrate was observed regarding the stool pattern and fecal ion loss. The best response was observed in subjects with missense and deletion mutations. Variable response to butyrate was also observed on SLC26A3 (DRA) and SLC26A6 (PAT1) gene expression in nasal epithelial cells of CLD patients.Conclusions
We demonstrate a genotype-dependency for butyrate therapeutic efficacy in CLD. The effect of butyrate is related in part on a different modulation of the expression of the two main apical membrane Cl- exchangers of epithelial cells, members of the SLC26 anion family.Trial registration
Australian New Zealand Clinical trial Registry ACTRN12613000450718.1000.