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971.
Opsins, the protein moieties of animal visual photo-pigments, have emerged as moonlighting proteins with diverse, light-dependent and -independent physiological functions. This raises the need to revise some basic assumptions concerning opsin expression, structure, classification, and evolution. 相似文献
972.
The last 50 years of climate‐induced melting of the Maliy Aktru glacier (Altai Mountains,Russia) revealed in a primary ecological succession 下载免费PDF全文
Roberto Cazzolla Gatti Anastasia Dudko Artem Lim Alena I. Velichevskaya Inna V. Lushchaeva Alice V. Pivovarova Stefano Ventura Erica Lumini Andrea Berruti Igor V. Volkov 《Ecology and evolution》2018,8(15):7401-7420
In this article, we report and discuss the results obtained from a survey of plants, microorganisms (bacteria and fungi), and soil elements along a chronosequence in the first 600 m of the Maliy Aktru glacier's forefront (Altai Mountains, Russia). Many glaciers of the world show effects of climate change. Nonetheless, except for some local reports, the ecological effects of deglaciation have been poorly studied and have not been quantitatively assessed in the Altai Mountains. Here, we studied the ecological changes of plants, fungi, bacteria, and soil elements that take the form of a primary ecological succession and that took place over the deglaciated soil of the Maliy Aktru glacier during the last 50 year. According to our measurements, the glacier lost about 12 m per year during the last 50 years. Plant succession shows clear signs of changes along the incremental distance from the glacier forefront. The analysis of the plant α‐ and β‐diversity confirmed an expected increase of them with increasing distance from the glacier forefront. Moreover, the analysis of β‐diversity confirmed the hypothesis of the presence of three main stages of the plant succession: (a) initial (pioneer species) from 30 to 100 m; (b) intermediate (r‐selected species) from 110 to 120–150 m; and (c) final (K‐selected species) from 150 to 550. Our study also shows that saprotrophic communities of fungi are widely distributed in the glacier retreating area with higher relative abundances of saprotroph ascomycetes at early successional stages. The evolution of a primary succession is also evident for bacteria, soil elements, and CO2 emission and respiration. The development of biological communities and the variation in geochemical parameters represent an irrefutable proof that climate change is altering soils that have been long covered by ice. 相似文献
973.
Mariano de Miguel Artal Olga Roca Chacón Montse Martínez-Alonso Marcos Serrano Godoy Jaume Mas Atance Roberto García Gutiérrez 《Revista espa?ola de geriatría y gerontología》2018,53(5):247-254
Objective
The aim of this study is to identify the risks factors for mortality and functional recovery in elderly patients admitted to hospital with a hip fracture.Materials and methods
Longitudinal prospective study in patients 80 years old or more and patients between 75 and 79 in residential home care with a hip fracture and with a past medical history of dementia or followed-up by the Geriatric Unit. A total of 359 patients were included, and the demographic data, previous functional status, comorbidity, type of fracture, and dementia were recorded. The data collected during admission included time to surgery, delirium, functional recovery, length of stay, placement at discharge, and mortality. Patients were followed-up for one year and details were collected on placement at the end of follow-up, functional recovery, medical complications, and mortality.Results
The baseline characteristics of the patients with a strong association with mortality after a hip fracture were old age (> 92 years), medical complications delaying surgery (HR 2.17; 95% CI; 1.27-3.73), diagnosis of dementia (HR 1.78; 95% CI; 1.15-2.75), or heart failure (HR 1.75; 95% CI; 1.12-2.75). The fitted multivariable regression models showed that functional impairment before the hip fracture or lack of functional recovery are associated with higher mortality, and patients with increased age, delirium, dementia, and previous functional impairment showed worse functional recovery.Conclusion
In the elderly patients with a hip fracture, increased age, comorbidity and previous functional status is associated with mortality. Functional recovery prognosis will depend on age, previous functional status, past medical history of dementia, and the presence of delirium during admission. 相似文献974.
975.
Kim JS Romero R Tarca AL LaJeunesse C Han YM Kim MJ Suh YL Draghici S Mittal P Gotsch F Kusanovic JP Hassan S Kim CJ 《Journal of cellular and molecular medicine》2008,12(4):1317-1330
There is a difference in the susceptibility to inflammation between the umbilical vein (UV) and the umbilical arteries (UAs). This led us to hypothesize that there is an intrinsic difference in the pro-inflammatory response between UA and UV. Real-time quantitative RT-PCR and microarray analysis revealed higher expression of interleukin (IL)-1β and IL-8 mRNA in the UV and differential expression of 567 genes between the UA and UV associated with distinct biological processes, including the immune response. Differential expression of human leukocyte antigen (HLA)-DRA mRNA between the UA and UV was due to unexpected HLA-DR+ cells migrating via the umbilical vessels into Wharton's jelly, more frequently in the UV. A significant proportion of these cells co-expressed CD45 and type I pro-collagen, and acquired CD163 or α-smooth muscle actin immunoreactivity in Wharton's jelly. Migrating cells were also found in the chorionic and stem villous vessels. Furthermore, the extent of migration increased with progression of gestation, but diminished in intrauterine growth restriction (IUGR). The observations herein strongly suggest that circulating foetal fibrocytes, routing via umbilical and placental vessels, are a reservoir for key cellular subsets in the placenta. This study reports fibrocytes in the human umbilical cord and placenta for the first time, and a novel role for both circulating foetal cells and the umbilical vessels in placental development, which is deranged in IUGR. 相似文献
976.
977.
Roberto Corti 《Plant biosystems》2013,147(4):505-514
Summary The author describes a Sporobolus Poiretii (R. et S.) Hitchc. and Oenothera sinuata L. stand in the «Selva» (forest) of S. Rossore (near Pisa). Earlier reports of these two adventive and perhaps naturalized species are mentioned. The author discussues the critical and complex sistematic definition, nomenclature and sinonimy of Sporobolus Poiretii in connection with the nearly related species Sporobolus indicus R. Br. The author prospects at the end how both Sp. Poiretii and Oe. sinuata can be inserted in the «Nuova Flora Analitica» of Italy, by Adriano Fiori. 相似文献
978.
Paolo AscenziAlberto Bertollini Roberto Santucci Gino AmiconiMassimo ColettaAlessandro DesideriBruno GiardinaFrancesca PolizioRoberto Scatena 《Journal of inorganic biochemistry》1993,50(4):263-272
The cooperative effect of inositol hexakisphosphate (IHP), bezafibrate (BZF), and clofibric acid (CFA) on the spectroscopic (EPR and absorbance) properties of the nitric oxide derivative of ferrous human hemoglobin (HbNO) has been investigated quantitatively. In the presence of IHP, BZF, and CFA, the X-band EPR spectra and the absorption spectra in the Soret region of HbNO display the same basic characteristics described in the presence of 2,3-diphosphoglycerate (2,3-DPG), which have been attributed to a low affinity conformation of the tetramer. Addition to HbNO of two allosteric effectors together (such as IHP and BZF, or IHP and CFA) further stabilizes the low affinity conformation of the ligated hemoprotein (i.e., HbNO). Moreover, in the presence of saturating amounts of IHP, the affinity of BZF and CFA for HbNO increases by about fifteenfold. Likewise, in the presence of both IHP and BZF, as well as in IHP and CFA, the oxygen affinity for ferrous human hemoglobin (Hb) is reduced with respect to that observed in the presence of IHP, BZF, or CFA alone, which in turn is lower than that reported in the absence of any allosteric effector. All the data were obtained at pH 7.0 (in 1.0 × 10−1 M N-[2-hydroxyethyl]piperazine-N′-[2-ethanesulfonic acid]/NaOH buffer system plus 1.0 × 10−1 M NaCl), as well as at 100 K and/or 20°C. The results here reported represent clearcut evidence for the cooperative and specific (i.e., functionally relevant) binding of IHP, BZF, and CFA to Hb. 相似文献
979.
Biometric Study of Acetoin Production in Hanseniaspora guilliermondii and Kloeckera apiculata 下载免费PDF全文
Patrizia Romano Giovanna Suzzi Roberto Zironi Giuseppe Comi 《Applied microbiology》1993,59(6):1838-1841
Gas chromatographic analysis by direct injection of samples yielded quantitative data on acetoin content. Ninety-six strains of Hanseniaspora guilliermondii and Kloeckera apiculata were investigated for the ability to produce acetoin in synthetic medium and in must. High-level production of acetoin was found to be a characteristic of both species. In synthetic medium, the two species were not significantly different with respect to sugar utilization and ethanol or acetoin production. In grape must, the two species were significantly different (P = 0.001) in acetoin production and K. apiculata exhibited a significantly negative correlation between acetoin production and either sugar consumption or ethanol production. Use of selected apiculate yeasts in mixed cultures with Saccharomyces cerevisiae seems promising for optimization of wine bouquet. 相似文献
980.
Flockhart AF Tree JJ Xu X Karpiyevich M McAteer SP Rosenblum R Shaw DJ Low CJ Best A Gannon V Laing C Murphy KC Leong JM Schneiders T La Ragione R Gally DL 《Molecular microbiology》2012,83(1):208-223
This study has identified horizontally acquired genomic regions of enterohaemorrhagic Escherichia coli O157:H7 that regulate expression of the type III secretion (T3S) system encoded by the locus of enterocyte effacement (LEE). Deletion of O-island 51, a 14.93 kb cryptic prophage (CP-933C), resulted in a reduction in LEE expression and T3S. The deletion also had a reduced capacity to attach to epithelial cells and significantly reduced E. coli O157 excretion levels from sheep. Further characterization of O-island 51 identified a novel positive regulator of the LEE, encoded by ecs1581 in the E. coli O157:H7 strain Sakai genome and present but not annotated in the E. coli strain EDL933 sequence. Functionally important residues of ECs1581 were identified based on phenotypic variants present in sequenced E. coli strains and the regulator was termed RgdR based on a motif demonstrated to be important for stimulation of gene expression. While RgdR activated expression from the LEE1 promoter in the presence or absence of the LEE-encoded regulator (Ler), RgdR stimulation of T3S required ler and Ler autoregulation. RgdR also controlled the expression of other phenotypes, including motility, indicating that this new family of regulators may have a more global role in E. coli gene expression. 相似文献