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1.
Seasonal reproductive cycles in three commercially exploited fishes from the slope waters off New Zealand 总被引:2,自引:0,他引:2
Reproductive cycles were investigated in orange roughy, Hoplostethus atlanticus , smooth oreo, Pseudocyttus maculatus , and black oreo dory, Allocyttus sp., from mid-slope waters (600–1300 m) around New Zealand from 1982 to 1985. Orange roughly displayed a mid-winter spawning period in July and August, whereas both dory species spawned in November and December. In all three species, the timing of spawning was consistent from year to year. Ovarian development in orange roughy and black oreo dory was found to be synchronous, with a single clutch of oocytes being matured for each spawning season. In males, testes of a given macroscopic stage were dominated by a single gamete stage, supporting the existence of a brief rather than prolonged spawning period. The possible relationship of spawning period to seasonal changes in the productivity of the surface water is discussed. 相似文献
2.
Cytokine production in a model of wound healing: the appearance of MIP-1, MIP-2, cachectin/TNF and IL-1 总被引:9,自引:1,他引:8
T J Fahey B Sherry K J Tracey S van Deventer W G Jones J P Minei S Morgello G T Shires A Cerami 《Cytokine》1990,2(2):92-99
Macrophages are essential for normal wound repair and many of their effects on healing wounds are likely to be mediated by the secretion of cytokines. This study examines the appearance of messenger RNA (mRNA) for cachectin/tumor necrosis factor (TNF), IL 1, and macrophage inflammatory proteins 1 and 2 (MIP-1 and MIP-2), as well as the mature peptides, in a model of wound healing using wound chambers. RNA for all four cytokines can be detected in wound inflammatory cells by polymerase chain reaction amplification throughout the first 7 days. Cachectin/TNF and IL 1 protein levels peaked on the first day after wound chamber implantation, and MIP-1 and MIP-2 were detected only on day 3. The data suggest that these cytokines participate in the early inflammatory response to wounding. 相似文献
3.
Seshi R. Sompuram Kodela Vani Brian Tracey Debra A. Kamstock Steven A. Bogen 《The journal of histochemistry and cytochemistry》2015,63(9):681-690
A new standardized immunohistochemistry (IHC) control for breast cancer testing comprises formalin-fixed human epidermal growth factor receptor 2, estrogen receptor, or progesterone receptor peptide antigens covalently attached to 8-µm glass beads. The antigen-coated beads are suspended in a liquid matrix that hardens upon pipetting onto a glass microscope slide. The antigen-coated beads remain in place through deparaffinization, antigen retrieval, and immunostaining. The intensity of the beads’ stain provides feedback regarding the efficacy of both antigen retrieval and immunostaining. As a first report, we tested the sensitivity and specificity of the new IHC controls (“IHControls”). To evaluate sensitivity, various staining problems were simulated. IHControls detected primary and secondary reagent degradation similarly to tissue controls. This first group of IHControls behaved similarly to tissue controls expressing high concentrations of the antigen. The IHControls were also able to detect aberrations in antigen retrieval, as simulated by sub-optimal times or temperatures. Specificity testing revealed that each antigen-coated bead was specific for its cognate IHC test antibody. The data support the conclusion that, like tissue controls, IHControls are capable of verifying the analytic components of an immunohistochemical stain. Unlike tissue controls, IHControls are prepared in large bulk lots, fostering day-to-day reproducibility that can be standardized across laboratories. 相似文献
4.
5.
Hemorrhage in mice produces alterations in B cell repertoires 总被引:1,自引:0,他引:1
Multiple organ system failure secondary to infection is the major cause of late deaths after trauma and hemorrhage. The production by B cells of antibodies directed against bacterial antigens is an important component of host defenses. In order to determine the effects of hemorrhage on B cell function, we examined hemorrhage-induced alterations in available (clonal precursors) and actual (plasma cells) B cell repertoires in the course of an immune response toward bacterial antigens. Hemorrhage produced greater than twofold decreases in the absolute frequency and number of clonal precursors specific for the bacterial antigens dextran, levan, and pneumococcal polysaccharide type II. After blood loss, there were decreases in absolute frequency, but not in numbers, of clonal precursors capable of producing antibodies against the nonbacterial antigens ovalbumin and mouse transferrin. Immunization with the bacterial antigen levan within 24 hr of hemorrhage resulted in approximately 50% fewer levan-specific plasma cells than that seen in normal, unhemorrhaged mice. These results demonstrate that hemorrhage produces marked alterations in B cell repertoires, which may contribute to postinjury abnormalities in host defenses. 相似文献
6.
7.
Tracey C. Bourner Enrique Vargas‐Osuna Trevor Williams Candido Santiago‐Alvarez Jenny S. Cory 《Biocontrol Science and Technology》1992,2(4):315-326
Agrotis segetum nuclear polyhedrosis virus (AsNPV) and granulosis virus (AsGV), propagated in laboratory cultures of A. segetum in England and A. ipsilon in Spain, respectively, were applied to plots of maize plants at the one‐ to four‐leaf stage of growth. Plots were arranged in a 6 x 6 Latin square design and infested with second‐instar A. segetum larvae (the common cutworm). Each virus was applied in separate treatments by two application methods; as an aqueous spray containing 0.1% Agral as a wetting agent, and as a bran bait. The NPV was applied at a rate of 4 X 1012 polyhedra/ha, and the GV at 4 X 1013 granules/ha. Soil and plants were sampled for larvae on three occasions following virus treatment: 24 h, 4 days and 11 days. The larvae were reared on diet in the laboratory, until death or pupation, to examine the rate and level of viral infection. Infection data showed 87.5% and 91% NPV infection and 12.5% and 55% GV infection in spray and bait treatments, respectively, in larvae sampled 24 h after treatment. In larvae sampled 4 days after treatment, the results were 78% and 100% NPV infection, and 13% and 6% GV infection. A total of only six larvae were retrieved on day 11. In both treatments larvae infected with AsNPV died significantly more rapidly and at an earlier instar than those infected with AsGV, indicating that AsNPV appears to have better potential as a control agent for A. segetum. 相似文献
8.
The relative numbers of short- and long-lived mitogen-reactive B cells in the peripheral pool were evaluated by studying the decay of lipopolysaccharide (LPS)-reactive B lymphocytes in LPS nonresponder, histocompatible hosts for periods of up to 3 wk after cell transfer. The results obtained demonstrate the existence of two major classes of mitogen-reactive B cells defined by life span. The "short-lived" cell component comprises about 80 to 90% of the reactive cells and decays with a life expectancy of 18 to 24 hr. The long-lived cell component, with life expectancies of 10 to 20 days, comprises about 10 to 20% of the reactive cells and is preferentially enriched in circulating B cells. The present ratio for short- and long-lived B cells implies a highly dynamic state for the immune system which must be advantageous in the selection of available repertoires. 相似文献
9.
Recent claims have challenged the view that most peripheral, mature B cells are long-lived, and propose rates of peripheral decay that are compatible with bone marrow production. This disagreement can only reflect differences in the protocols and methods used to measure peripheral lymphocyte life spans. We have now assessed toxic or other nonselective effects of hydroxyurea treatment on the survival and migration of peripheral, noncycling cells, as well as possible reasons for exaggerated decays of LPS-reactive B cells transferred to LPS nonresponder hosts, the two methods leading to conclusions of short life spans. We also studied general effects on cell survival introduced by either repeated [3H]thymidine injections or the stress associated with surgery, thoracic duct cannulation in particular--methods with which the notion of long life spans had been established. The results failed to show toxic or nonselective effects of hydroxyurea treatments and artificial decays of LPS-reactive cells in adoptive hosts. In contrast, the present experiments demonstrate that both the stress associated with surgery and repeated [3H] thymidine administration profoundly deplete a pool of short-lived B cells, consequently selecting for an apparent higher proportion of long-lived cells. 相似文献
10.
Calcium Enhances In Vitro Free Radical-Induced Damage to Brain Synaptosomes, Mitochondria, and Cultured Spinal Cord Neurons 总被引:2,自引:1,他引:1
Preincubation of rat brain synaptosomes with xanthine and xanthine oxidase (X/XO) in Ca2+-free Krebs buffer resulted in a 27% inhibition of synaptosomal gamma-aminobutyric acid (GABA) uptake. Addition of 1.5 mM CaCl2 increased the inhibition with X/XO to 46%, and inhibition was essentially complete when the calcium ionophore A23187 also was included. In other studies, preincubation of purified rat brain mitochondria with the combination of X/XO and 4 microM CaCl2 produced a significant (38%) decrease in state 3 respiration with glutamate/malate as substrate that was not seen with either X/XO or Ca2+ alone. Similar results were obtained using cultured mouse spinal cord neurons in which incubation with X/XO/ADP/FeCl2 and A23187 produced membrane damage as assessed by a 32% reduction of neuronal Na+, K+-ATPase activity. Neither X/XO/ADP/FeCl2 nor A23187 alone caused detectable inhibition. These results demonstrate the synergistic damaging effect of free radicals and Ca2+ on membrane function. In addition, they suggest that free radical-induced peroxidation of membrane lipid, occurring focally during complete or nearly complete ischemia in vivo, could result in intense cellular perturbation when coupled with increased intracellular Ca2+. 相似文献