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71.
Hila Shamoon Shlomo Cain Uri Shanas Avi Bar-Massada Yariv Malihi Idan Shapira 《European Journal of Wildlife Research》2018,64(3):35
Recreation activities in developed landscapes may add additional stressors that affect wildlife spatial and temporal activity patterns. We assessed medium to large mammal species response to a tourist scenic route in an agro-ecological mosaic landscape of the Shikma region, Israel. We placed 60 camera traps in an agro-ecological matrix and recorded mammals during three seasons between 2015 and 2017. We used N-mixture models to estimate mammal activity in relation with proximity to the scenic route and additional anthropogenic related factors such as traffic volume and land use. Anthropogenic development and activities had negative effects on large, endangered species, and none or positive on smaller, commensal species. Our results suggest an expansion of human recreation activity may have adverse outcomes on apex predators, which can cause a chain reaction and lead to meso-predator release, ultimately affecting prey species. The results emphasize the need for land managers to be extra cautious when attempting to add additional stressors (i.e., recreation activity) to developed landscapes such as the study area. Such landscapes can function as healthy ecosystems and provide suitable habitats for wildlife given that land managers are aware and account for wildlife-limiting factors in future development plans. 相似文献
72.
73.
Yael Korem Kohanim Tomer Milo Moriya Raz Omer Karin Alon Bar Avi Mayo Netta Mendelson Cohen Yoel Toledano Uri Alon 《Molecular systems biology》2022,18(8)
Thyroid disorders are common and often require lifelong hormone replacement. Treating thyroid disorders involves a fascinating and troublesome delay, in which it takes many weeks for serum thyroid‐stimulating hormone (TSH) concentration to normalize after thyroid hormones return to normal. This delay challenges attempts to stabilize thyroid hormones in millions of patients. Despite its importance, the physiological mechanism for the delay is unclear. Here, we present data on hormone delays from Israeli medical records spanning 46 million life‐years and develop a mathematical model for dynamic compensation in the thyroid axis, which explains the delays. The delays are due to a feedback mechanism in which peripheral thyroid hormones and TSH control the growth of the thyroid and pituitary glands; enlarged or atrophied glands take many weeks to recover upon treatment due to the slow turnover of the tissues. The model explains why thyroid disorders such as Hashimoto''s thyroiditis and Graves'' disease have both subclinical and clinical states and explains the complex inverse relation between TSH and thyroid hormones. The present model may guide approaches to dynamically adjust the treatment of thyroid disorders. 相似文献
74.
Lyubenova L Götz C Golan-Goldhirsh A Schröder P 《International journal of phytoremediation》2007,9(6):465-473
Interactions between heavy metals, glutathione, glutathione S-transferase (GST), and glutathione reductase (GR) are being investigated by many working groups, but evaluation of the direct effect of Cd+ on these enzymes in vitro is lacking. We report here the effect of cadmium (10, 50, 100, 250 microM CdSO4) on partially purified enzymes from Calystegia sepium. Plants were grown under normal field conditions without metals and the enzymes were extracted by Tris buffer and partially purified by ammonium sulphate fractionation and gel filtration. Glutathione S-transferase activity was measured with different substrates, i.e., 1-chloro-2,4-dinitrobenzene (CDNB), p-nitrobenzylchloride (NBC), and the herbicide Fluorodifen. GST activity was significantly lower in leaf compared to stem, flower, and rhizome and the inhibitory effect of Cd was obtained with NBC and Fluorodifen substrates at 250 microM. There was no effect of Cd on GR activity up to 250 microM. 相似文献
75.
76.
Shemesh R Toporik A Levine Z Hecht I Rotman G Wool A Dahary D Gofer E Kliger Y Soffer MA Rosenberg A Eshel D Cohen Y 《The Journal of biological chemistry》2008,283(50):34643-34649
G-protein-coupled receptors (GPCRs) represent an important group of targets for pharmaceutical therapeutics. The completion of the human genome revealed a large number of putative GPCRs. However, the identification of their natural ligands, and especially peptides, suffers from low discovery rates, thus impeding development of therapeutics based on these potential drug targets. We describe the discovery of novel GPCR ligands encrypted in the human proteome. Hundreds of potential peptide ligands were predicted by machine learning algorithms. In vitro screening of selected 33 peptides on a set of 152 GPCRs, including a group of designated orphan receptors, was conducted by intracellular calcium measurements and cAMP assays. The screening revealed eight novel peptides as potential agonists that specifically activated six different receptors in a dose-dependent manner. Most of the peptides showed distinct stimulatory patterns targeted at designated and orphan GPCRs. Further analysis demonstrated a significant in vivo effect for one of the peptides in a mouse inflammation model. 相似文献
77.
The oxidation of cytochromeb
561 by ATP was measured in submitochondrial particles inhibited by antimycin. The redox potential of the bulk (M phase) was controlled by the ratio of fumarate:succinate, and the oxidation of cytochromeb was calculated and expressed as a change in redox potential (E
h) measured in millivolts. The oxidation of cytochromeb
561 is an energy-driven reaction affected only by the component of the proton motive force. The oxidation (measured in millivolts) is a function of the phosphate potential, reaching a maximal value of 40 mV at GATP<–12 kcal/mole. The maximal measured value of ATP-dependent was 100 mV. Thus only a fraction of the membrane potential effects the redox state of cytochromeb
561. In contrast to the ATP-induced oxidation of cytochromeb
561, cytochromeb
566 is in redox equilibrium with fumarate succinate either in the presence or in the absence of ATP. The selective oxidation ofb
561 is explained within the term of theQ cycle as a reflection of on the electron electrochemical potential. The positive electric potential of theC phase causes cytochromeb
566 to act as oxidant with respect to cytochromeb
561. In the presence of antimycin cytochromeb
561 cannot equilibrate with the quinone and undergoes oxidation, while cytochromeb
566 reequilibrates with the quinone and thus regains redox equilibrium with the fumarate succinate redox buffer.Abbreviations used: ETPH, phosphorylating submitochondrial particles; TMPD,N
1
N
1
NN-tetramethyl-p-phenylenediamine; FCCP, carbonylcyanidep-trifluoromethoxyphenylhydrazone; Mes, 2-(N-morpholino) ethanesulfonic acid. 相似文献
78.
Knappskog PM Majewski J Livneh A Nilsen PT Bringsli JS Ott J Boman H 《American journal of human genetics》2003,72(2):375-383
In 1978, Sohar et al. described a strikingly peculiar syndrome in two Israeli sisters. These young women responded to environmental temperatures of 18 degrees C-7 degrees C with profuse sweating on large segments on their back and chest. Both had additional abnormalities, including a high-arched palate, nasal voice, depressed nasal bridge, inability to fully extend their elbows, and kyphoscoliosis. We have observed this disorder in two Norwegian brothers. Genome-wide screening in the two families, followed by saturation marker studies and linkage analysis, identified a 1.4-Mb homozygous candidate region on chromosome 19p12. The maximum multipoint LOD score was 4.22. In both families, DNA sequencing of 25 genes within the candidate region identified potentially deleterious CRLF1 sequence variants that were not found in unaffected control individuals. Our findings confirm that the cold-induced sweating syndrome is an autosomal recessive disorder that is probably caused by impaired function of the CRLF1 gene, and they suggest important developmental functions for human CRLF1. 相似文献
79.
80.
Jacob-Wilk Debora Goldschmidt Eliezer E. Riov Joseph Sadka Avi Holland Doron 《Plant molecular biology》1997,35(5):661-666
Maturing citrus fruit undergo pigment changes which can be enhanced by exogenous ethylene. In order to identify genes induced by ethylene in citrus fruit peel, we cloned the gene c-thi1. mRNA corresponding to c-thi1 increased gradually in the peel during natural fruit maturation and in response to ethylene. GA3 pretreatment reduced the inductive effect of ethylene. Levels of c-thi1 increased also in juice sacs but the effect of ethylene was much less prominent. c-thi1 is homologous to yeast and plant genes encoding for an enzyme belonging to the pathway of thiamine biosynthesis. The data suggest that thiamine is involved in citrus fruit maturation. 相似文献