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1.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
2.
Blidingia minima var. ramifera is reported for the first time in eastern North America. It occurs in the Gulf of St. Lawrence, Nova Scotia and in Maine. In the estuary of the West and Rights Rivers (Antigonish Harbour, Nova Scotia) it is the most common intertidal alga and during its maximum growth period (June-August) covers 75–90% of the intertidal zone for several km of shoreline at the mouth of the Rights River. In culture, spore germination and early development were typical of the taxon as described from Europe. The taxon is raised to specific status as Blidingia ramifera stat. nov. Blidingia subsalsa is confirmed from New England based on observations of spore germination in plants from Maine and Connecticut. 相似文献
3.
Thomas F. Holzman Christine C. Chung Rohinton Edalji David A. Egan Earl J. Gubbins Annemarie Rueter Gail Howard Lana K. Yang Terry M. Pederson Grant A. Krafft et al. 《Journal of Protein Chemistry》1990,9(6):663-672
The gene for human preprorenin was obtained from total RNA prepared from primary human chorion cells. An expression vector was constructed containing an SV40 early promoter, a human preprorenin cDNA, bovine growth hormone poly-A addition signal, and a dihydrofolate reductase (dhfr) expression cassette. This vector was inserted into the DXB-11 Chinese hamster ovary (CHO) cell line. The recombinant protein was exported by CHO cells into the tissue culture media. At harvest the prorenin levels ranged from 1–5 mg/L. For prorenin isolation the cell culture supernatants were processed by filtration, concentration, dialysis, and batch extraction. Preparative-scale isolation of prorenin was accomplished using blue-dye chromatography and size-exclusion chromatography. The isolated prorenin yielded a single SDS-gel band with Mr 40,000. The proprotein was characterized with respect to N-terminal sequence and N-linked sugar composition. Trypsin-activated renin prepared from the proprotein was characterized with respect to N-terminal sequence andpH-activity profile. Enzyme activity was measured with a newly developed fluorogenic peptide substrate containing the P6-P3 sequence of human angiotensinogen. 相似文献
4.
α1 -Adrenergic Receptor-Mediated Downregulation of Angiotensin II Receptors in Neuronal Cultures 总被引:1,自引:0,他引:1
Previous evidence has suggested that brain catecholamine levels are important in the regulation of central angiotensin II receptors. In the present study, the effects of norepinephrine and 3,4-dihydroxyphenylethylamine (dopamine) on angiotensin II receptor regulation in neuronal cultures from rat hypothalamus and brainstem have been examined. Both catecholamines elicit significant decreases in [125I]angiotensin II-specific binding to neuronal cultures prepared from normotensive rats, effects that are dose dependent and that are maximal within 4-8 h of preincubation. Saturation and Scatchard analyses revealed that the norepinephrine-induced decrease in the binding is due to a decrease in the number of angiotensin II receptors in neuronal cultures, with little effect on the receptor affinity. Norepinephrine has no significant actions on [125I]angiotensin II binding in cultures prepared from spontaneously hypertensive rats. The downregulation of angiotensin II receptors by norepinephrine or dopamine is blocked by alpha 1-adrenergic and not by other adrenergic antagonists, a result suggesting that this effect is initiated at the cell surface involving alpha 1-adrenergic receptors. This is further supported by our data indicating a parallel downregulation of specific alpha 1-adrenergic receptors elicited by norepinephrine. In summary, these results show that norepinephrine and dopamine are able to alter the regulation of neuronal angiotensin II receptors by acting at alpha 1-adrenergic receptors, which is a novel finding. 相似文献
5.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
6.
The clam shrimpEulimnadia texana is an androdioecious crustacean in which hermaphrodites may self fertilize or outcross with males but cannot outcross with other hermaphrodites. Outcrossing is maintained within most populations of this species despite the high genetic cost of sex, suggesting that compensating factors provide an advantage to outcrossing. We hypothesized that one such benefit would be the production of larger clutch sizes resulting from outcrossed matings. To test this prediction, we recorded the body sizes and clutch sizes of hermaphrodites which mated via selfing or bia outcrossing. Clutch sizes showed significant, almost exponential, increases as body size increased in both selfing and outcrossing hernmaphrodites. The rate of this increase was the same for both groups, and there was no significant difference in clutch size when body size was controlled for between the two fertilization types. 相似文献
7.
Dirofilaria immitis: heartworm infection alters pulmonary artery endothelial cell behavior 总被引:1,自引:0,他引:1
Mupanomunda Maria; Williams Jeffrey F.; Mackenzie Charles D.; Kaiser Lana 《Journal of applied physiology》1997,82(2):389-398
Mupanomunda, Maria, Jeffrey F. Williams, Charles D. Mackenzie, and Lana Kaiser. Dirofilaria immitis:heartworm infection alters pulmonary artery endothelial cell behavior.J. Appl. Physiol. 82(2): 389-398, 1997.Thepathogenesis of filariasis has generally been attributed to eitherphysical presence of the adult parasites or the host's immune responseto the parasites. However, the spectrum of filariasis cannot beentirely explained by these causes, and other mechanisms must beoperative. It is now evident that factors released by filarialparasites likely contribute to the pathogenesis of filarial diseases.Adult heartworms (Dirofilaria immitis) reside in the rightheart and pulmonary artery, so the pulmonary artery should be exposedto the highest concentration of filarial factors. We tested thehypothesis that endothelium-dependent relaxation is altered in the invitro pulmonary artery from heartworm-infected dogs. Relaxationresponses to endothelium-dependent vasodilators (methacholine,bradykinin, substance P, and A-23187) and the non-endothelium-dependent vasodilator nitroglycerin and contractile responses were measured inrings of pulmonary artery from control and heartworm-infected dogs.Endothelium-dependent relaxation was assessed in the presence andabsence of inhibitors of nitric oxide synthase, cyclooxygenase, andguanylate cyclase. Responses to methacholine, substance P, and A-23187,but not to bradykinin, nitroglycerin, norepinephrine, or KCl, weredepressed in pulmonary artery from heartworm-infected dogs whencompared with control, suggesting that changes in endothelial cell andnot vascular smooth muscle behavior are involved in altered relaxation.The mechanism of endothelium-dependent relaxation in control pulmonaryartery appears to involve nitric oxide in the case of methacholine andboth nitric oxide and a cyclooxygenase product in the case ofbradykinin and A-23187. The mechanism of endothelium-dependentrelaxation in pulmonary artery from heartworm-infected dogs was notclearly elucidated. These data provide no evidence that heartworminfection globally influences either endothelial cell receptor functionor the vascular smooth muscle guanylate cyclase guanosine 3,5-cyclicmonophosphate system, making it likely that changes in intracellularsignaling are primarily responsible for the observed alteration ofendothelium-mediated relaxation. Alteration of endothelial cellfunction by filarial parasites may be an important component inthe pathology associated with filariasis. 相似文献
8.
Adriana Vergs Alexandra H. Campbell Georgina Wood Lana Kajlich Aaron M. Eger Derrick Cruz Madelaine Langley Damon Bolton Melinda A. Coleman Jennifer Turpin Michaelie Crawford Nigel Coombes Adam Camilleri Peter D. Steinberg Ezequiel M. Marzinelli 《Ecological Management & Restoration》2020,21(2):74-85
Operation Crayweed focuses on the restoration of underwater forests that disappeared from the coastline of Sydney, Australia’s largest city, 40 years previously. We show how a combination of science, hands‐on restoration, community engagement and art has helped the project to reach its goals as well as raise awareness about the importance of underwater kelp forests that are experiencing global decline. 相似文献
9.
de Sousa Sylvia Morais de Oliveira Christiane Abreu Andrade Daniele Luiz de Carvalho Chainheny Gomes Ribeiro Vitória Palhares Pastina Maria Marta Marriel Ivanildo Evódio de Paula Lana Ubiraci Gomes Gomes Eliane Aparecida 《Journal of Plant Growth Regulation》2021,40(2):867-877
Journal of Plant Growth Regulation - The rising demand for agricultural commodities in developing countries has put increasing pressure on land resources for higher yields, with associated growth... 相似文献
10.
Elizabeth A. Sinclair Craig D. H. Sherman John Statton Craig Copeland Andrew Matthews Michelle Waycott Kor‐Jent van Dijk Adriana Vergs Lana Kajlich Ian M. McLeod Gary A. Kendrick 《Ecological Management & Restoration》2021,22(1):10-21
Three case studies involving two temperate Australian seagrass species – Pondweed (Ruppia tuberosa) and Ribbon Weed (Posidonia australis) – highlight different approaches to their restoration. Seeds and rhizomes were used in three collaborative programmes to promote new approaches to scale up restoration outcomes. 相似文献