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Editorial: Getting to the heart of developmental toxicities. FRONTIERS IN TOXICOLOGY 2023; 5:1138470. [PMID: 36726487 PMCID: PMC9886310 DOI: 10.3389/ftox.2023.1138470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 01/09/2023] [Indexed: 01/17/2023] Open
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Deletion of murine slc29a4 modifies vascular responses to adenosine and 5-hydroxytryptamine in a sexually dimorphic manner. Physiol Rep 2021; 8:e14395. [PMID: 32170814 PMCID: PMC7070170 DOI: 10.14814/phy2.14395] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/18/2020] [Accepted: 02/19/2020] [Indexed: 12/15/2022] Open
Abstract
Equilibrative nucleoside transporter 4 (ENT4), encoded by SLC29A4, mediates the flux of both 5‐hydroxytryptamine (5‐HT) and adenosine across cell membranes. We hypothesized that loss of ENT4 function in mice would modify the effects of these established regulators of vascular function. Male and female wild‐type (WT) and slc29a4‐null (ENT4‐KO) mice were compared with respect to their hemodynamics and mesenteric vascular function. Male ENT4‐KO mice had a complete loss of myogenic tone in their mesenteric resistance arteries. This was accompanied by a decrease in blood flow in the superior mesenteric artery in the male ENT4‐KO mice, and a reduced responsiveness to 5‐HT. In contrast, endothelium‐dependent relaxations of mesenteric arteries from female ENT4‐KO mice were more sensitive to Ca2+‐activated K+ (KCa) channel blockade than WT mice. Female ENT4‐KO mice also demonstrated an enhanced vasodilatory response to adenosine in vivo that was not seen in males. Ketanserin (5‐HT2A inhibitor) and GR55562 (5‐HT1B/1D inhibitor) decreased 5‐HT‐induced tone, but only ketanserin inhibited the relaxant effect of 5‐HT in mesenteric arteries. 5‐HT‐evoked increases in tone were elevated in arteries from ENT4‐KO mice upon block of endothelial relaxant pathways, with arteries from female ENT4‐KO mice showing the greatest increase. Adenosine A2b receptor expression was decreased, while other adenosine transporter subtypes, as well as adenosine deaminase and adenosine kinase were increased in mesenteric arteries from male, but not female, ENT4‐KO mice. These findings indicate that deletion of slc29a4 leads to sex‐specific changes in vascular function with significant consequences for regulation of blood flow and pressure by adenosine and 5‐HT.
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Differences in relative capacities of oxidative phosphorylation pathways may explain sex- and tissue-specific susceptibility to vision defects due to mitochondrial dysfunction. Mitochondrion 2020; 56:102-110. [PMID: 33271347 DOI: 10.1016/j.mito.2020.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 10/09/2020] [Accepted: 11/18/2020] [Indexed: 01/03/2023]
Abstract
Mitochondrial dysfunction is a major cause and/or contributor to the development and progression of vision defects in many ophthalmologic and mitochondrial diseases. Despite their mechanistic commonality, these diseases exhibit an impressive variety in sex- and tissue-specific penetrance, incidence, and severity. Currently, there is no functional explanation for these differences. We measured the function, relative capacities, and patterns of control of various oxidative phosphorylation pathways in the retina, the eyecup, the extraocular muscles, the optic nerve, and the sciatic nerve of adult male and female rats. We show that the control of mitochondrial respiratory pathways in the visual system is sex- and tissue-specific and that this may be an important factor in determining susceptibility to mitochondrial dysfunction between these groups. The optic nerve showed a low relative capacity of the NADH pathway, depending on complex I, compared to other tissues relying mainly on mitochondria for energy production. Furthermore, NADH pathway capacity is higher in females compared to males, and this sexual dimorphism occurs only in the optic nerve. Our results propose an explanation for Leber's hereditary optic neuropathy, a mitochondrial disease more prevalent in males where the principal tissue affected is the optic nerve. To our knowledge, this is the first study to identify and provide functional explanations for differences in the occurrence and severity of visual defects between tissues and between sexes. Our results highlight the importance of considering sex- and tissue-specific mitochondrial function in elucidating pathophysiological mechanisms of visual defects.
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Aging causes alterations in level and expression pattern of von Willebrand factor in an organ-specific manner. Atherosclerosis 2020. [DOI: 10.1016/j.atherosclerosis.2020.10.254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Maternal Iron Deficiency Elicits Changes in Placental Development and Alters Fetal Growth Trajectories. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.02821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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AGING IS ASSOCIATED WITH INCREASED VON WILLEBRAND FACTOR EXPRESSION. Can J Cardiol 2019. [DOI: 10.1016/j.cjca.2019.07.515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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7
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Editorial: Post-translational Modifications in Plant Nuclear Signaling: Novel Insights Into Responses to Environmental Changes. FRONTIERS IN PLANT SCIENCE 2019; 10:104. [PMID: 30804971 PMCID: PMC6378320 DOI: 10.3389/fpls.2019.00104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
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AGING CORRELATES WITH ORGAN-SPECIFIC REGULATION OF VON WILLEBRAND FACTOR EXPRESSION. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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The Evolution of HD2 Proteins in Green Plants. TRENDS IN PLANT SCIENCE 2016; 21:1008-1016. [PMID: 27789157 DOI: 10.1016/j.tplants.2016.10.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/28/2016] [Accepted: 10/04/2016] [Indexed: 05/18/2023]
Abstract
In eukaryotes, protein deacetylation is carried out by two well-conserved histone deacetylase (HDAC) families: RPD3/HDA1 and SIR2. Intriguingly, model plants such as Arabidopsis express an additional plant-specific HDAC family, termed type-2 HDACs (HD2s). Transcriptomic analyses from more than 1300 green plants generated by the 1000 plants (1KP) consortium showed that HD2s appeared early in green plant evolution, the first members being detected in several streptophyte green alga. The HD2 family has expanded via several rounds of successive duplication; members are expressed in all major green plant clades. Interestingly, angiosperm species express new HD2 genes devoid of a zinc-finger domain, one of the main structural features of HD2s. These variants may have been associated with the origin and/or the biology of the ovule/seed.
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Reduced uterine perfusion pressure decreases functional capillary density in skeletal muscle. Am J Physiol Heart Circ Physiol 2015; 309:H2002-7. [PMID: 26475590 DOI: 10.1152/ajpheart.00641.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/13/2015] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to examine the functional and structural capillary density in the reduced uterine perfusion pressure (RUPP) model, which when performed during pregnancy is an established animal model of preeclampsia. We hypothesized that the RUPP model would be associated with capillary rarefaction and impaired capillary perfusion, which would be more pronounced in the pregnant state. Female Sprague-Dawley rats (n = 32) were randomized to nonpregnancy (Nonpregnant) or breeding (Pregnant) at 12 wk of age and again to RUPP or SHAM surgeries on gestational day (GD) 14 (or equivalent age in nonpregnant rats). On GD 20 (or equivalent), capillary structure and perfusion of the extensor digitorum longus were imaged using digital intravital video microscopy. Functional videos were analyzed by a blinded observer to measure capillary density, expressed as capillaries per millimeter intersecting three staggered reference lines (200 μm). Flow was scored as the percentage of capillaries having 1) continuous, 2) intermittent, or 3) stopped flow. Total capillary density was not different between groups. There was a main effect of RUPP surgery resulting in decreased continuous flow vessels (P < 0.01) and increased stopped flow (P < 0.01), which was driven by differences between pregnant animals (Continuous flow: pregnant SHAM 80.1 ± 7.8% vs. pregnant RUPP 67.8 ± 11.2%, P < 0.05) (Stopped flow: pregnant SHAM 8.7 ± 3.2% vs. pregnant RUPP 17.9 ± 5.7%, P < 0.01). Our results demonstrate that the RUPP surgery is associated with a decrease in functional capillary density in skeletal muscle that is more pronounced in the pregnant state, which may contribute to the vascular pathophysiology observed in preeclampsia.
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The Reduced Uterine Perfusion Pressure (RUPP) Model of Preeclampsia Causes Decreased Capillary Perfusion in Skeletal Muscle. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.lb551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Intralipid Reverses Propofol‐Mediated Hypotension in Rats. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.624.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Uterine vasculature remodeling in human pregnancy involves functional macrochimerism by endothelial colony forming cells of fetal origin. Stem Cells 2014; 31:1363-70. [PMID: 23554274 PMCID: PMC3813980 DOI: 10.1002/stem.1385] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 02/26/2013] [Accepted: 03/04/2013] [Indexed: 12/19/2022]
Abstract
The potency of adult-derived circulating progenitor endothelial colony forming cells (ECFCs) is drastically surpassed by their fetal counterparts. Human pregnancy is associated with robust intensification of blood flow and vascular expansion in the uterus, crucial for placental perfusion and fetal supply. Here, we investigate whether fetal ECFCs transmigrate to maternal bloodstream and home to locations of maternal vasculogenesis, primarily the pregnant uterus. In the first instance, endothelial-like cells, originating from mouse fetuses expressing paternal eGFP, were identified within uterine endothelia. Subsequently, LacZ or enhanced green fluorescent protein (eGFP)-labeled human fetal ECFCs, transplanted into immunodeficient (NOD/SCID) fetuses on D15.5 pregnancy, showed similar integration into the mouse uterus by term. Mature endothelial controls (human umbilical vein endothelial cells), similarly introduced, were unequivocally absent. In humans, SRY was detected in 6 of 12 myometrial microvessels obtained from women delivering male babies. The copy number was calculated at 175 [IQR 149-471] fetal cells per millimeter square endothelium, constituting 12.5% of maternal vessel lumina. Cross-sections of similar human vessels, hybridized for Y-chromosome, positively identified endothelial-associated fetal cells. It appears that through ECFC donation, fetuses assist maternal uterine vascular expansion in pregnancy, potentiating placental perfusion and consequently their own fetal supply. In addition to fetal growth, this cellular mechanism holds implications for materno-fetal immune interactions and long-term maternal vascular health.
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Eastern Canadian Colorectal Cancer Consensus Conference: standards of care for the treatment of patients with rectal, pancreatic, and gastrointestinal stromal tumours and pancreatic neuroendocrine tumours. ACTA ACUST UNITED AC 2013; 20:e455-64. [PMID: 24155642 DOI: 10.3747/co.20.1638] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Halifax, Nova Scotia, October 20-22, 2011. Health care professionals involved in the care of patients with colorectal cancer participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management of rectal cancer, including pathology reporting, neoadjuvant systemic and radiation therapy, surgical techniques, and palliative care of rectal cancer patients. Other topics discussed include multidisciplinary cancer conferences, treatment of gastrointestinal stromal tumours and pancreatic neuroendocrine tumours, the use of folfirinox in pancreatic cancer, and treatment of stage ii colon cancer.
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Effect of Maxillomandibular Advancement Surgery on Blood Pressure in Patients With Obstructive Sleep Apnea. J Oral Maxillofac Surg 2012. [DOI: 10.1016/j.joms.2012.06.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Eastern Canadian colorectal cancer consensus conference: application of new modalities of staging and treatment of gastrointestinal cancers. Curr Oncol 2012; 19:169-74. [PMID: 22670096 PMCID: PMC3364767 DOI: 10.3747/co.19.931] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Ottawa, Ontario, October 22-23, 2010. Health care professionals involved in the care of patients with colorectal cancer participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer, such as the use of epidermal growth factor inhibitors in metastatic colon cancer, the benefit of calcium and magnesium with oxaliplatin chemotherapy, the role of microsatellites in treatment decisions for stage II colon cancer, the staging and treatment of rectal cancer, and the management of colorectal and metastatic pancreatic cancers.
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Objective Outcomes of Maxillomandibular Advancement Surgery for Treatment of Obstructive Sleep Apnea. J Oral Maxillofac Surg 2011. [DOI: 10.1016/j.joms.2011.06.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Characterization of N-glycosylated receptors for the tobacco lectin in the plant cell nucleus. Comp Biochem Physiol A Mol Integr Physiol 2008. [DOI: 10.1016/j.cbpa.2008.04.424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Perinatal iron deficiency results in increased visceral adiposity in male Wistar rats. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.719.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Impact of dietary iron deficiency on tissue levels in developing rats: Differential response to aging, gender and pregnancy. FASEB J 2007. [DOI: 10.1096/fasebj.21.6.a810-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
During the last decade, heme oxygenase (HO) and carbon monoxide (CO) have garnered substantial research interest in terms of cell and organ regulation, especially as they bear on the central nervous system, organ transplantation, and the cardiovascular system. While the enzymatic mechanism, substrates, and products of HO are well known, it is not clear whether the cardiovascular system derives its supply of the heme substrate through de novo synthesis or uptake from the extracellular milieu. The objective of the present study was to test the latter possibility in rat aorta and to determine the influence of plasma proteins that bind heme in vivo, viz. hemopexin and albumin. Aortic tissue was exposed to [14C]heme in vitro, and the concentration and time dependence of heme uptake was assessed. The presence of hemopexin or albumin in the incubation medium dramatically decreased heme uptake by the aorta. Heme uptake by aortic tissue was not altered after induction of HO-1, which would be expected to increase tissue heme demand. In summary, the rat, isolated aorta was capable of obtaining heme from its external milieu, but this was obtunded in the presence of the plasma proteins hemopexin or albumin. For normal physiological situations, heme uptake may not be a usual source of substrate for vascular HO and hemoenzymes such as nitric oxide synthase, soluble guanylyl cyclase, and cyclooxygenase.Key words: heme uptake, vasculature, heme oxygenase, hemopexin.
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MESH Headings
- Animals
- Aorta, Thoracic/cytology
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Canada
- Carbon Radioisotopes
- Heme/metabolism
- Heme Oxygenase (Decyclizing)/drug effects
- Heme Oxygenase (Decyclizing)/metabolism
- Heme Oxygenase-1
- Hemopexin/pharmacology
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Rats
- Rats, Sprague-Dawley
- S-Nitroso-N-Acetylpenicillamine/pharmacology
- Serum Albumin/pharmacology
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Reliability of Information Collected by Proxy in Family Studies of Alzheimer’s Disease. Neuroepidemiology 2001; 20:105-11. [PMID: 11359077 DOI: 10.1159/000054768] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The study evaluated the reliability of data obtained from proxy informants. The index subjects in this study were 81 nondemented participants in the Multi-Institutional Research in Alzheimer Genetic Epidemiology (MIRAGE) study. These index subjects and 159 proxy informants, identified by the index subjects, participated in the study. The kappa statistic with multiple raters per subject (for dichotomous variables) and the intraclass correlation coefficient (for continuous variables) were used to measure reliability. Among proxy respondents who provided answers, there was excellent agreement between proxy responses and the responses of the index subjects (0.7 < or = kappa < or =0.9), with the exception of questions about head injury (kappa = 0.4). A large proportion (>90%) of the proxy informants in this study were able to provide information on most items. Higher nonresponse rates (as high as 30%) were observed for medication history and women's health questions. This study supports the reliability of proxy responses for most categories of questions that are elicited in typical epidemiological studies, including the MIRAGE study.
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Abstract
Cryptogein is a 98-amino acid proteinaceous elicitor of tobacco defense reactions. Specific binding of cryptogein to high affinity binding sites on tobacco plasma membranes has been previously reported (K(d) = 2 nM; number of binding sites: 220 fmol/mg of protein). In this study, biochemical characterization of cryptogein binding sites reveals that they correspond to a plasma membrane glycoprotein(s) with an N-linked carbohydrate moiety, which is involved in cryptogein binding. Radiation inactivation experiments performed on tobacco plasma membrane preparations indicated that cryptogein bound specifically to a plasma membrane component with an apparent functional molecular mass of 193 kDa. Moreover, using the homobifunctional cross-linking reagent disuccinimidyl suberate and tobacco plasma membranes incubated with (125)I-cryptogein, we identified, after SDS-polyacrylamide gel electrophoresis and autoradiography, two (125)I-cryptogein linked N-glycoproteins of about 162 and 50 kDa. Similar results were obtained using Arabidopsis thaliana and Acer pseudoplatanus plasma membrane preparations, whereas cryptogein did not induce any effects on the corresponding cell suspensions. These results suggest that either cryptogein binds to nonfunctional binding sites, homologues to those present in tobacco plasma membranes, or that a protein involved in signal transduction after cryptogein recognition is absent or inactive in both A. pseudoplatanus and A. thaliana.
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Involvement of plasma membrane proteins in plant defense responses. Analysis of the cryptogein signal transduction in tobacco. Biochimie 1999; 81:663-8. [PMID: 10433120 DOI: 10.1016/s0300-9084(99)80123-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cryptogein, a 98 amino acid protein secreted by the fungus Phytophthora cryptogea, induces a hypersensitive response and systemic acquired resistance in tobacco plants (Nicotiana tabacum var Xanthi). The mode of action of cryptogein has been studied using tobacco cell suspensions. The recognition of this elicitor by a plasma membrane receptor leads to a cascade of events including protein phosphorylation, calcium influx, potassium and chloride effluxes, plasma membrane depolarization, activation of a NADPH oxidase responsible for active oxygen species (AOS) production and cytosol acidification, activation of the pentose phosphate pathway, and activation of two mitogen-activated protein kinase (MAPK) homologues. The organization of the cryptogein responses reveals that the earliest steps of the signal transduction pathway involve plasma membrane activities. Their activation generates a complex network of second messengers which triggers the specific physiological responses. This study may contribute to our understanding of plant signaling processes because elicitors and a variety of signals including hormones, Nod factors, light, gravity and stresses share some common transduction elements and pathways.
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Comparison of binding properties and early biological effects of elicitins in tobacco cells. PLANT PHYSIOLOGY 1998; 118:1317-26. [PMID: 9847105 PMCID: PMC34747 DOI: 10.1104/pp.118.4.1317] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/1998] [Accepted: 08/21/1998] [Indexed: 05/20/2023]
Abstract
Elicitins are a family of small proteins secreted by Phytophthora species that have a high degree of homology and elicit defense reactions in tobacco (Nicotiana tabacum). They display acidic or basic characteristics, the acidic elicitins being less efficient in inducing plant necrosis. In this study we compared the binding properties of four elicitins (two basic and two acidic) and early-induced signal transduction events (Ca2+ influx, extracellular medium alkalinization, and active oxygen species production). The affinity for tobacco plasma membrane-binding sites and the number of binding sites were similar for all four elicitins. Furthermore, elicitins compete with one another for binding sites, suggesting that they interact with the same receptor. The four elicitins induced Ca2+ influx, extracellular medium alkalinization, and the production of active oxygen species in tobacco cell suspensions, but the intensity and kinetics of these effects were different from one elicitin to another. As a general observation the concentrations that induce similar levels of biological activities were lower for basic elicitins (with the exception of cinnamomin-induced Ca2+ uptake). The qualitative similarity of early events induced by elicitins indicates a common transduction scheme, whereas fine signal transduction tuning is different in each elicitin.
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Pharmacokinetics of single intravenous and oral doses of dolasetron mesylate in healthy elderly volunteers. J Clin Pharmacol 1996; 36:903-10. [PMID: 8930777 DOI: 10.1002/j.1552-4604.1996.tb04757.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Dolasetron mesylate (MDL 73,147EF, Anzemet; Hoechst Marion Roussel, Laval, Canada) is a 5-HT3 receptor antagonist undergoing clinical evaluation for use as an antiemetic agent. The pharmacokinetics of dolasetron and its reduced metabolite (MDL 74,156) were studied after administration of single intravenous and oral doses of dolasetron mesylate 2.4 mg/kg in 18 healthy elderly subjects. Expressed as the dolasetron base, this dose was 1.8 mg/kg. Dolasetron was rapidly metabolized to the reduced metabolite, which appeared in plasma within 10 minutes after intravenous or oral administration. The mean half-life (t1/2) of dolasetron was 0.24 hours after intravenous administration and 0.50 hours after oral administration. The pharmacokinetic parameters of the reduced metabolite were similar after intravenous and oral administration. The apparent absolute bioavailability of the reduced metabolite was 89%, and it had an elimination t1/2 of approximately 7 hours and an apparent volume of distribution (Vd beta) of 4.69 L/kg. Dolasetron was not detected in urine. Metabolites were excreted in urine almost completely within 24 hours of administration. The primary metabolite detected in urine was the (+)-enantiomer of the reduced metabolite, which accounted for 25.35% (+/- 7.79%) and 18.88% (+/- 7.65%) of the intravenous and oral doses, respectively. Hydroxylated metabolites accounted for 5% or less of the total dose via either route. The pharmacokinetics of the reduced metabolite after single intravenous or oral doses in elderly volunteers were consistent with pharmacokinetics observed in both young healthy men and cancer patients receiving high-dose cisplatin chemotherapy. Dosage adjustments of dolasetron mesylate on the basis of age do not appear to be necessary.
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Preparing for managed care during a health information management system selection project. JOURNAL OF AHIMA 1995; 66:49-51. [PMID: 10151547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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