Prolactin and survival in deionized water of the marine form (trachurus) of the threespine stickleback, Gasterosteus aculeatus L.

The marine form (trachurus) of the threespine stickleback (Gasterosteus aculeatus L.) showed rapid mortality in deionized water in the early winter, and prolactin injection could significantly reduce this mortality although it could not completely prevent it. A single prolactin injection 24 h before transfer of fish to deionized water was apparently as effective as three prior injections (on alternate days). There was no obvious dose–response relationship. However, there appears to be an optimum range since both a low dose of 1 μg/g and a high dose of 30 μg/g were less effective than the intermediate doses which did not differ significantly amongst themselves.On the other hand, prolactin was ineffective when the fish were transferred to deionized water only 3 h after the injection. Both the solvent-injected and prolactin-injected fish in this case showed a more rapid mortality rate than the uninjected fish.When the fish were transferred 48 h after the injection, prolactin appeared to be even more effective than when the fish were transferred 24 h after the injection, but in this case slightly larger doses were apparently required.

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Nonlinear Dose-Response Relationship in the Immune System following Exposure to Ionizing Radiation: Mechanisms and Implications

Nonlinearity in Biology Toxicology Medicine ◽

10.1080/15401420390844483 ◽

2003 ◽

Vol 1 (1) ◽

pp. 154014203908444 ◽

Cited By ~ 43

Author(s):

Shu-Zheng Liu

Keyword(s):

T Lymphocyte ◽

Dose Response ◽

Low Dose ◽

Cell Types ◽

High Dose ◽

Response Relationship ◽

Low Dose Radiation ◽

Dose Response Relationship ◽

Dose Radiation ◽

Different Doses

The health effects of low-dose radiation (LDR) have been the concern of the academic spheres, regulatory bodies, governments, and the public. Among these effects, the most important is carcinogenesis. In view of the importance of immune surveillance in cancer control, the dose-response relationship of the changes in different cell types of the immune system after whole-body irradiation is analyzed on the basis of systemic data from the author's laboratory in combination with recent reports in the literature. For T lymphocytes J- or inverted J-shaped curves are usually demonstrated after irradiation, while for macrophages dose-response curves of chiefly stimulation with irregular patterns are often observed. The intercellular reactions between the antigen presenting cell (APC) and T lymphocyte (TLC) in the immunologic synapse via expression of surface molecules and secretion of cytokines by the two cell types after different doses of radiation are illustrated. The different pathways of signal transduction thus facilitated in the T lymphocyte by different doses of radiation are analyzed to explain the mechanism of the phenomenon of low-dose stimulation and high-dose suppression of immunity. Experimental and clinical data are cited to show that LDR retards tumor growth, reduces metastasis, increases the efficacy of conventional radiotherapy and chemotherapy as well as alleviates the suppression of immunity due to tumor burden. The incidence of thymic lymphoma after high-dose radiation is lowered by preexposure to low-dose radiation, and its mechanism is supposed to be related to the stimulation of anticancer immunity induced by low-dose radiation. Recent reports on lowering of standardized cancer mortality rate and all cause death rate of cohorts occupationally exposed to low-dose radiation from the US, UK, and Canada are cited.

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Effects of Enterococcus sp. isolated from deep seawater on inhibition of allergic responses in mice

British Journal Of Nutrition ◽

10.1017/s0007114508158998 ◽

2008 ◽

Vol 102 (1) ◽

pp. 3-7 ◽

Cited By ~ 2

Author(s):

Masatoshi Kondoh ◽

Atsushi Hayashi ◽

Mariko Okamori ◽

Chie Motonaga ◽

Tadao Enomoto ◽

...

Keyword(s):

Low Dose ◽

High Dose ◽

Response Relationship ◽

Dose Response Relationship ◽

Deep Seawater ◽

Colony Forming Units ◽

High Doses ◽

Cedar Pollen ◽

Eosinophil Accumulation ◽

Medium Dose

The objective of the present study was to assess the effects of Enterococcus sp. strain TN-3 isolated from deep seawater on inhibition of eosinophil accumulation, IgE production and active cutaneous anaphylaxis (ACA). We investigated the effects of viable and non-viable TN-3 on allergen-induced peritoneal eosinophil accumulation in mice. Viable (5·4 × 1010 colony-forming units per 60 mg) or non-viable TN-3 (60 mg) was orally administered to BALB/c mice that had been sensitised with the cedar pollen (Cryptomeria japonica) allergen. Oral administration of non-viable TN-3 was effective in suppressing eosinophil accumulation while viable TN-3 was ineffective. We also examined the dose–response relationship for non-viable TN-3 in regard to eosinophil accumulation, IgE production and ACA in allergen-primed mice. Non-viable TN-3 was orally administered at doses of 15 mg (low dose), 30 mg (medium dose) and 60 mg (high dose) to BALB/c mice that had been sensitised with cedar pollen allergen. The anti-allergic effects expressed as inhibition of eosinophil accumulation, IgE production and ACA were found at the low and high doses, but not at the medium dose. These results suggest that non-viable TN-3 exhibited anti-allergic effects at doses of 15 and 60 mg.

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Effects of exposure to low-dose ionizing radiation on changing platelets: a prospective cohort study

Environmental Health and Preventive Medicine ◽

10.1186/s12199-021-00939-z ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Ning Liu ◽

Yang Peng ◽

Xinguang Zhong ◽

Zheng Ma ◽

Suiping He ◽

...

Keyword(s):

Radiation Dose ◽

Ionizing Radiation ◽

Dose Response ◽

Low Dose ◽

Linear Trend ◽

Hematological Parameters ◽

Response Relationship ◽

Dose Response Relationship ◽

Spline Models ◽

Cumulative Radiation Dose

Abstract Background Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers. Methods Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship. Results We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (Ptrend = 0.258), the non-linear trend tested was statistically significant (Pnon-linear = 0.007). Overall, there was a correlation between changing platelets and cumulative radiation dose (a change of βa 0.008 × 109/L during biennially after adjusting for gender, age at baseline, service at baseline, occupation, medical level, and smoking habits; 95% confidence interval [CI] = 0.003,0.014 × 109/L). Moreover, we also found positive first and then negative dose-response relationships between cumulative radiation dose and changing platelets by restricted cubic spline models, while there were negative patterns of the baseline service not less than 10 years (− 0.015 × 109/L, 95% CI = − 0.024, − 0.007 × 109/L) and radiation nurses(− 0.033 × 109/L, 95% CI = − 0.049, − 0.016 × 109/L). Conclusion We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing.

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Defining hormesis: the necessary tool to clarify experimentally the low dose–response relationship

Human & Experimental Toxicology ◽

10.1191/0960327102ht219oa ◽

2002 ◽

Vol 21 (2) ◽

pp. 103-104 ◽

Cited By ~ 6

Author(s):

G Carelli ◽

I Iavicoli

Keyword(s):

Dose Response ◽

Low Dose ◽

Experimental Models ◽

Assessment Criteria ◽

Response Relationship ◽

Dose Response Relationship ◽

Specific Context ◽

Definition Of ◽

Time Specific ◽

Made In

The authors comment on Calabrese and Baldwin's paper ‘Defining Hormesis’, which, to date, is the first attempt to provide a definition of hormesis that goes beyond the different interpretations of this phenomenon reported in the literature. While appreciating the effort made in this study to place hormesis in a general and at the same time specific context, the authors believe some clarifications are needed as regards the quantitative features of this phenomenon. In this connection, they speculate on whether Calabrese and Baldwin think it appropriate to include hormesis assessment criteria in the document, referring in particular to those reported in a previous paper. The authors share Calabrese and Baldwin's conclusion that future experimental models designed to study hormetic phenomena must necessarily include the time factor, which not only guarantees this phenomenon will be detected, but is also able to detect the specific type of hormesis.

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Oral steroid-sparing effect of high-dose inhaled corticosteroids in asthma

European Respiratory Journal ◽

10.1183/13993003.01147-2019 ◽

2019 ◽

Vol 55 (1) ◽

pp. 1901147 ◽

Cited By ~ 7

Author(s):

Ingrid Maijers ◽

Nethmi Kearns ◽

James Harper ◽

Mark Weatherall ◽

Richard Beasley

Keyword(s):

Dose Response ◽

Oral Corticosteroid ◽

Inhaled Corticosteroids ◽

Adrenal Suppression ◽

Oral Steroid ◽

Systemic Effects ◽

High Dose ◽

Response Relationship ◽

Dose Response Relationship ◽

Sparing Effect

BackgroundThe proportion of the efficacy of high-dose inhaled corticosteroids (ICS) in oral corticosteroid-dependent asthma that is due to systemic effects is uncertain. This study aimed to estimate the ICS dose–response relationship for oral corticosteroid-sparing effects in oral corticosteroid-dependent asthma, and to determine the proportion of oral corticosteroid-sparing effects due to their systemic effects, based on the comparative dose–response relationship of ICS versus oral corticosteroids on adrenal suppression.MethodsSystematic review and meta-analysis of randomised controlled trials reporting oral corticosteroid-sparing effects of high-dose ICS in oral corticosteroid-dependent asthma. In addition, reports of oral corticosteroid to ICS dose-equivalence in terms of adrenal suppression were retrieved. The primary outcome was the proportion of the oral corticosteroid-sparing effect of ICS that could be attributed to systemic absorption, per 1000 µg increase of ICS, expressed as a ratio. This ratio estimates the oral corticosteroid sparing effect of ICS due to systemic effects.Results11 studies including 1283 participants reporting oral corticosteroid-sparing effects of ICS were identified. The prednisone dose decrease per 1000 µg increase in ICS varied from 2.1 mg to 4.9 mg, depending on the type of ICS. The ratio of the prednisone-sparing effect due to the systemic effects per 1000 µg of fluticasone propionate was 1.02 (95% CI 0.68–2.08) and for budesonide was 0.93 (95% CI 0.63–1.89).ConclusionIn patients with oral corticosteroid-dependent asthma, the limited available evidence suggests that the majority of the oral corticosteroid-sparing effect of high-dose ICS is likely to be due to systemic effects.

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Regions of beta 2 and beta 4 responsible for differences between the steady state dose-response relationships of the alpha 3 beta 2 and alpha 3 beta 4 neuronal nicotinic receptors.

The Journal of General Physiology ◽

10.1085/jgp.105.6.745 ◽

1995 ◽

Vol 105 (6) ◽

pp. 745-764 ◽

Cited By ~ 33

Author(s):

B N Cohen ◽

A Figl ◽

M W Quick ◽

C Labarca ◽

N Davidson ◽

...

Keyword(s):

Dose Response ◽

Nicotinic Receptors ◽

Relative Sensitivity ◽

The Other ◽

Response Relationship ◽

Wild Type ◽

Dose Response Relationship ◽

Neuronal Nicotinic Receptors ◽

Hill Slope ◽

Beta 2

We constructed chimeras of the rat beta 2 and beta 4 neuronal nicotinic subunits to locate the regions that contribute to differences between the acetylcholine (ACh) dose-response relationships of the alpha 3 beta 2 and alpha 3 beta 4 receptors. Expressed in Xenopus oocytes, the alpha 3 beta 2 receptor displays an EC50 for ACh approximately 20-fold less than the EC50 of the alpha 3 beta 4 receptor. The apparent Hill slope (n(app)) of alpha 3 beta 2 is near one whereas the alpha 3 beta 4 receptor displays an n(app) near two. Substitutions within the first 120 residues convert the EC50 for ACh from one wild-type value to the other. Exchanging just beta 2:104-120 for the corresponding region of beta 4 shifts the EC50 of ACh dose-response relationship in the expected direction but does not completely convert the EC50 of the dose-response relationship from one wild-type value to the other. However, substitutions in the beta 2:104-120 region do account for the relative sensitivity of the alpha 3 beta 2 receptor to cytisine, tetramethylammonium, and ACh. The expression of beta 4-like (strong) cooperativity requires an extensive region of beta 4 (beta 4:1-301). Relatively short beta 2 substitutions (beta 2:104-120) can reduce cooperativity to beta 2-like values. The results suggest that amino acids within the first 120 residues of beta 2 and the corresponding region of beta 4 contribute to an agonist binding site that bridges the alpha and beta subunits in neuronal nicotinic receptors.

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