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51.
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Theodora Lola-Luz† Martin Downes Richard Dunne† 《Agricultural and Forest Entomology》2005,7(2):121-126
Abstract 1 Outdoor trials were carried out during 2001–02 on strawberries grown in commercial growing bags naturally infested with black vine weevil larvae (BVW) Otiorhynchus sulcatus in Co. Wexford, Ireland. 2 The two nematode isolates used in these trials were Heterorhabditis megidis (UK211) and Heterorhabditis downesi (K122), both laboratory cultured. Growing bags received nematodes either once (May 2001), twice (May and October 2001) or three times (May, October 2001 and May 2002). Ten days after each application date, nine blocks (of the total 27) were randomly selected, destructively assessed and discarded. 3 The single application (May 2001) resulted in a mortality of black vine weevil larvae, of 93.4% with H. megidis and 51.3% with H. downesi, compared with the control treatment at that date. Respective figures after the double application (May 2001 and October 2001) were 78.9 and 77.6% and after the triple application (May 2001, October 2001 and May 2002) the figures were 93.7 and 88.1%. 4 Results from these trials clearly indicate that entomopathogenic nematodes are good alternatives to chemical control of the black vine weevil on strawberries grown in growing bags in Ireland. 相似文献
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Theodora M. Mauro R. Rivkah Isseroff Richard Lasarow Pamela A. Pappone 《The Journal of membrane biology》1993,132(3):201-209
Summary In vivo and in vitro, keratinocyte differentiation is linked with increased extracellular Ca2+. In order to correlate ion channels with cell differentiation and investigate keratinocyte membrane responses to Ca2+, keratinocyte single channel currents were studied using the patch-clamp technique. The most frequently observed channel was a 14 pS nonspecific cation channel. This channel was permeable to Ca2+ and activated by physiological concentrations of Ca2+. We also found a 35 pS Cl– channel whose open probability increased with depolarization. Finally, a 70 pS K+ channel was seen only in cell-attached or nystatin-permeabilized patches. We correlated channel types with staining for involucrin, an early marker of keratinocyte differentiation. While the nonspecific cation channel and Cl– channel were seen in both involucrin positive and involucrin negative cells, all channels in which the K+ channel activity was present were involucrin positive. Membrane currents through these channels may be one pathway by which signals for keratinocyte proliferation or differentiation are sent.This work was supported in part by a National Institutes of Health grant K08 AR01853-03 and a National Science Foundation grant DCB-9009915 (to T.M.M.); National Institutes of Health Research Career Development Award K04 ARO 1803 and AR 39031 (to R.R.I.) and a National Institutes of Health grant GM-44840 (to P.A.P.). 相似文献
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Holland S Lodwig E Sideri T Reader T Clarke I Gkargkas K Hoyle DC Delneri D Oliver SG Avery SV 《Genome biology》2007,8(12):R268
Background
The serious biological consequences of metal toxicity are well documented, but the key modes of action of most metals are unknown. To help unravel molecular mechanisms underlying the action of chromium, a metal of major toxicological importance, we grew over 6,000 heterozygous yeast mutants in competition in the presence of chromium. Microarray-based screens of these heterozygotes are truly genome-wide as they include both essential and non-essential genes. 相似文献57.
Choi EH Demerjian M Crumrine D Brown BE Mauro T Elias PM Feingold KR 《American journal of physiology. Regulatory, integrative and comparative physiology》2006,291(6):R1657-R1662
Many cutaneous disorders are adversely affected by psychological stress (PS), but the responsible mechanisms are poorly understood. Recent studies have demonstrated that PS decreases epidermal proliferation and differentiation, impairs permeability barrier homeostasis, and decreases stratum corneum integrity. PS also increases the production of endogenous glucocorticoids (GC), and both systemic and topical GC cause adverse effects on epidermal structure and function similar to those observed with PS. We therefore hypothesized that increased endogenous GC in PS mediates its adverse cutaneous effects. To test this hypothesis, we used two independent approaches, administering either RU-486, a GC receptor antagonist that inhibits GC action, or antalarmin, a corticotropin-releasing hormone (CRH) receptor antagonist that prevents increased GC production in the face of PS. Inhibition of either GC action or production prevents the PS-induced decline in epidermal cell proliferation and differentiation, impairment in permeability barrier homeostasis, and decrease in stratum corneum (SC) integrity. Moreover, the pathophysiological basis for the abnormality in permeability barrier homeostasis; i.e., decreased lamellar body production and secretion, is restored toward normal by inhibition of GC action. Similarly, the mechanistic basis for the decrease in SC integrity, i.e., a reduction in corneodesmosomes, is also normalized by inhibition of GC action. Thus many of the adverse effects of PS on epidermal structure and function can be attributed to increased endogenous GC and conversely, approaches that either reduce GC production or action might benefit cutaneous disorders that are provoked or exacerbated by PS. 相似文献
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Evangelos J. Giamarellos-Bourboulis Maria Raftogiannis Anastasia Antonopoulou Fotini Baziaka Pantelis Koutoukas Athina Savva Theodora Kanni Marianna Georgitsi Aikaterini Pistiki Thomas Tsaganos Nikolaos Pelekanos Sofia Athanassia Labrini Galani Efthymia Giannitsioti Dimitra Kavatha Flora Kontopidou Maria Mouktaroudi Garyfallia Poulakou Vissaria Sakka Periklis Panagopoulos Antonios Papadopoulos Kyriaki Kanellakopoulou Helen Giamarellou 《PloS one》2009,4(12)
Background
The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host.Methodology/Principal Findings
Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-18, interferon (FN)-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs).Conclusions/Significance
Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza. 相似文献59.
60.
Gkrania-Klotsas E Ye Z Cooper AJ Sharp SJ Luben R Biggs ML Chen LK Gokulakrishnan K Hanefeld M Ingelsson E Lai WA Lin SY Lind L Lohsoonthorn V Mohan V Muscari A Nilsson G Ohrvik J Chao Qiang J Jenny NS Tamakoshi K Temelkova-Kurktschiev T Wang YY Yajnik CS Zoli M Khaw KT Forouhi NG Wareham NJ Langenberg C 《PloS one》2010,5(10):e13405