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1.
Somayeh Shokri Shahab Mahmoudvand Reza Taherkhani Fatemeh Farshadpour 《Journal of cellular physiology》2019,234(3):2143-2151
Coronavirus (CoV) infections are commonly associated with respiratory and enteric disease in humans and animals. In 2012, a new human disease called Middle East respiratory syndrome (MERS) emerged in the Middle East. MERS was caused by a virus that was originally called human coronavirus-Erasmus Medical Center/2012 but was later renamed as Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV causes high fever, cough, acute respiratory tract infection, and multiorgan dysfunction that may eventually lead to the death of the infected individuals. The exact origin of MERS-CoV remains unknown, but the transmission pattern and evidence from virological studies suggest that dromedary camels are the major reservoir host, from which human infections may sporadically occur through the zoonotic transmission. Human to human transmission also occurs in healthcare facilities and communities. Recent studies on Middle Eastern respiratory continue to highlight the need for further understanding the virus-host interactions that govern disease severity and infection outcome. In this review, we have highlighted the major mechanisms of immune evasion strategies of MERS-CoV. We have demonstrated that M, 4a, 4b proteins and Plppro of MERS-CoV inhibit the type I interferon (IFN) and nuclear factor-κB signaling pathways and therefore facilitate innate immune evasion. In addition, nonstructural protein 4a (NSP4a), NSP4b, and NSP15 inhibit double-stranded RNA sensors. Therefore, the mentioned proteins limit early induction of IFN and cause rapid apoptosis of macrophages. MERS-CoV strongly inhibits the activation of T cells with downregulation of antigen presentation. In addition, uncontrolled secretion of interferon ɣ-induced protein 10 and monocyte chemoattractant protein-1 can suppress proliferation of human myeloid progenitor cells. 相似文献
2.
Latitudinal comparison of altitudinal changes in forest structure,leaf-type,and species richness in humid monsoon Asia 总被引:10,自引:0,他引:10
M. Ohsawa 《Plant Ecology》1995,121(1-2):3-10
A new template for mountain vegetation zonation along latitudinal gradients is proposed for examining geographical pattern of various forest attributes in humid monsoon Asia. The contrasting temperature regime in tropical and temperate mountains, i.e., the former is a non-seasonal, temperature-sum controlled environment, and the latter is a seasonal, low temperature limiting environment, leads to different altitudinal patterns of tree height distribution and species richness. In the tropical mountains, both tree height and species richness decrease steeply, and the tree height often stepwise. The decline of tree height and species diversity in the temperate mountains is far less pronounced except near the forest limit. Both trends are explained by their temperature regime. 相似文献
3.
4.
Sylvia Hofmann Sabine Kraus Tsering Dorge Michael Nothnagel Georg Miehe 《Journal of Biogeography》2014,41(11):2162-2172
5.
Jin Wei Mia Madel Alfajaro Peter C. DeWeirdt Ruth E. Hanna William J. Lu-Culligan Wesley L. Cai Madison S. Strine Shang-Min Zhang Vincent R. Graziano Cameron O. Schmitz Jennifer S. Chen Madeleine C. Mankowski Renata B. Filler Neal G. Ravindra Victor Gasque Fernando J. de Miguel Ajinkya Patil Huacui Chen Craig B. Wilen 《Cell》2021,184(1):76-91.e13
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7.
East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided. 相似文献
8.
M. Matabos S. Plouviez S. Hourdez D. Desbruyères P. Legendre A. Warén D. Jollivet E. Thiébaut 《Journal of Biogeography》2011,38(3):575-594
Aim Deep‐sea hydrothermal vents have now been reported along all active mid‐ocean ridges and back‐arc basins, but the boundaries of biogeographic entities remain questionable owing to methodological issues. Here we examine biogeographic patterns of the vent fauna along the East Pacific Rise (EPR) and determine the relative roles of regional and local factors on the distribution of biodiversity associated with mussel beds along a poorly explored zone, the southern EPR (SEPR). Location East Pacific Rise. Methods A species list of macrobenthic invertebrates along the EPR was compiled from the literature and supplemented with data recovered during the French research cruise BIOSPEEDO carried out in 2004 along the SEPR. Biogeographic patterns were assessed by combining the identification of morphological species with a molecular barcoding approach. A multivariate regression tree (MRT) analysis was performed to identify any geographic breaks, and an empirical distribution of species richness was compared with predictions provided by a mid‐domain effect model. Macrofaunal community structure associated with mussel beds along the SEPR was analysed in relation to environmental factors using cluster and canonical redundancy analyses. Results Sequencing of the cytochrome c oxidase subunit I gene revealed the occurrence of several cryptic species complexes along the EPR, with the equator separating the southern and northern clades. Furthermore, during the BIOSPEEDO cruise at least 10 still unnamed species were collected between 7°25′ S and 21°33′ S. The shift in community structure identified by MRT analysis was located south of 17°34′ S or south of 13°59′ S, depending on the data used, suggesting that the southern part of the SEPR (17°25′–21°33′ S) constitutes a biogeographic transition zone in the vent fauna along the EPR. At a regional scale, latitude combined with the type of venting was significantly correlated with the community structure associated with mussel beds. Main conclusions Together, the molecular data, in situ observations, and the distribution of species suggest that the high diversity of vent fauna species presently observed between 17°25′ S and 21°33′ S is probably a result of the overlap of several distinct biogeographic provinces. We argue that this area thus constitutes a biogeographic vent fauna transition zone along the EPR. 相似文献
9.
Alan F. Sved John E. Ottenweller Walter N. Tapp Michael E. Thompson Benjamin H. Natelson 《Life sciences》1985,37(24):2313-2317
Hamsters of the BIO 14.6 strain characteristically develop cardiomyopathy as they age, and hamsters of this strain have overt signs of heart failure by 11 months of age. Plasma levels of the posterior pituitary hormone arginine-vasopressin (AVP) were found to be elevated (approximately 2-fold) in 11 month old BIO 14.6 hamsters, compared to age-matched hamsters of a control strain. AVP appeared inappropriately elevated in these animals, since they were neither hyperosmotic nor markedly hypotensive. The elevated levels of AVP observed in these animals appears to contribute to vasomotor tone, since intravenous adminstration of a specific antagonist of the vasoconstrictor action of AVP [d(CH2)5Ome(TYR)AVP] elicited a fall in arterial pressure (9±2 mm Hg, n=6, p<0.05). The AVP antagonist had no effect on arterial pressure in hamsters of a control strain, and vehicle administration had no effect on arterial pressure in either strain. These data indicate that inappropriately elevated levels of AVP contribute to the cardiovascular state of myopathic hamsters. Since elevated plasma AVP has been noted in human congestive heart failure, these results suggest that AVP may contribute to the cardiovascular status during congestive heart failure. 相似文献
10.
Sanda Clejan Platon J. Collipp Vaddanahally T. Maddaiah 《Archives of biochemistry and biophysics》1980,203(2):744-752
The effects of hypophysectomy and subsequent administration of growth hormone, thyroxine, insulin, and testosterone were examined in rat liver for the relationship between the thermotropic effects on State 3 respiration (ADP induced) and fatty acid composition of the phospholipid fraction of intact mitochondria as well as of inner membrane vesicles. The Arrhenius profile for energy-linked (succinate) State 3 respiration of mitochondria from hypophysectomized rats lacked the discontinuity at 23.5 °C seen with mitochondria from normal rats. After injections of the hormones the discontinuity representing the transition temperature from gel to liquid crystalline state of lipids occurred at different temperatures: 18.5 °C for growth hormone, 26.0 °C for thyroxine, 19.5 °C for growth hormone + thyroxine, 27.6 °C for insulin, and 25.3 °C for testosterone. The energy of activation between 37.5 and 23.5 °C was 1.9 times greater for hypophysectomy than for controls. Growth hormone was the most effective in restoring the energy of activation to normal, above as well as below transition temperature. The effect of thyroxine appears to be due to a larger stimulation of the State 4 respiration than that of growth hormone, insulin, or testosterone, especially at higher temperatures. Phospholipids extracted from intact mitochondria or inner membrane vesicles of hypophysectomized rats contained less arachidonic acid (20:4) and more linoleic acid (18:2) than those of normal rats. In addition, the contents of some of the minor fatty acids were also changed. Calculated unsaturation index showed an 18.8 and 14.9% depletion in unsaturation in whole mitochondria and inner membranes, respectively. Among the different hormones used to treat the hypophysectomized rats, growth hormone was the most effective in restoring the transition temperature and fatty acid composition to normal levels and increasing the gain in body weight. Although the other hormones increased total unsaturation index to some extent, some of the individual fatty acids were affected differently. Good correlation exists between the unsaturation index of mitochondrial fatty acids and transition temperature of State 3 respiration. These results strongly suggest a role for the hormones, particularly growth hormone, in the control of mitochondrial membrane fluidity of hypophysectomized rat liver, through fatty acid composition of phospholipids. 相似文献