Intersex occurrence in rainbow trout (Oncorhynchus mykiss) male fry chronically exposed to ethynylestradiol.

This study aimed to investigate the male-to-female morphological and physiological transdifferentiation process in rainbow trout (Oncorhynchus mykiss) exposed to exogenous estrogens. The first objective was to elucidate whether trout develop intersex gonads under exposure to low levels of estrogen. To this end, the gonads of an all-male population of fry exposed chronically (from 60 to 136 days post fertilization--dpf) to several doses (from environmentally relevant 0.01 µg/L to supra-environmental levels: 0.1, 1 and 10 µg/L) of the potent synthetic estrogen ethynylestradiol (EE2) were examined histologically. The morphological evaluations were underpinned by the analysis of gonad steroid (testosterone, estradiol and 11-ketotestosterone) levels and of brain and gonad gene expression, including estrogen-responsive genes and genes involved in sex differentiation in (gonads: cyp19a1a, ER isoforms, vtg, dmrt1, sox9a2; sdY; cyp11b; brain: cyp19a1b, ER isoforms). Intersex gonads were observed from the first concentration used (0.01 µg EE2/L) and sexual inversion could be detected from 0.1 µg EE2/L. This was accompanied by a linear decrease in 11-KT levels, whereas no effect on E2 and T levels was observed. Q-PCR results from the gonads showed downregulation of testicular markers (dmrt1, sox9a2; sdY; cyp11b) with increasing EE2 exposure concentrations, and upregulation of the female vtg gene. No evidence was found for a direct involvement of aromatase in the sex conversion process. The results from this study provide evidence that gonads of male trout respond to estrogen exposure by intersex formation and, with increasing concentration, by morphological and physiological conversion to phenotypic ovaries. However, supra-environmental estrogen concentrations are needed to induce these changes.

Synergism of peptide receptor-targeted Auger electron radiation therapy with anti-angiogenic compounds in a mouse model of neuroendocrine tumors.

BACKGROUND Neuroendocrine tumors are well vascularized and express specific cell surface markers, such as somatostatin receptors and the glucagon-like peptide-1 receptor (GLP-1R). Using the Rip1Tag2 transgenic mouse model of pancreatic neuroendocrine tumors (pNET), we have investigated the potential benefit of a combination of anti-angiogenic treatment with targeted internal radiotherapy. METHODS [Lys40(Ahx-DTPA-111In)NH2]-exendin-4, a radiopeptide that selectively binds to GLP-1R expressed on insulinoma and other neuroendocrine tumor cells, was co-administered with oral vatalanib (an inhibitor of vascular endothelial growth factor receptors (VEGFR)) or imatinib (a c-kit/PDGFR inhibitor). The control groups included single-agent kinase inhibitor treatments and [Lys40(Ahx-DTPA-natIn)NH2]-exendin-4 monotherapy. For biodistribution, Rip1Tag2 mice were pre-treated with oral vatalanib or imatinib for 0, 3, 5, or 7 days at a dose of 100 mg/kg. Subsequently, [Lys40(Ahx-DTPA-111In)NH2]-exendin-4 was administered i.v., and the biodistribution was assessed after 4 h. For therapy, the mice were injected with 1.1 MBq [Lys40(Ahx-DTPA-111In)NH2]-exendin-4 and treated with vatalanib or imatinib 100 mg/kg orally for another 7 days. Tumor volume, tumor cell apoptosis and proliferation, and microvessel density were quantified. RESULTS Combination of [Lys40(Ahx-DTPA-111In)NH2]-exendin-4 and vatalanib was significantly more effective than single treatments (p < 0.05) and reduced the tumor volume by 97% in the absence of organ damage. The pre-treatment of mice with vatalanib led to a reduction in the tumor uptake of [Lys40(Ahx-DTPA-111In)NH2]-exendin-4, indicating that concomitant administration of vatalanib and the radiopeptide was the best approach. Imatinib did not show a synergistic effect with [Lys40(Ahx-DTPA-111In)NH2]-exendin-4. CONCLUSION The combination of 1.1 MBq of [Lys40(Ahx-DTPA-111In)NH2]-exendin-4 with 100 mg/kg vatalanib had the same effect on a neuroendocrine tumor as the injection of 28 MBq of the radiopeptide alone but without any apparent side effects, such as radiation damage of the kidneys.

Developmental oestrogen exposure differentially modulates IGF-I and TNF-α expression levels in immune organs of Yersinia ruckeri-challenged young adult rainbow trout (Oncorhynchus mykiss).

Intensified aquaculture has strong impact on fish health by stress and infectious diseases and has stimulated the interest in the orchestration of cytokines and growth factors, particularly their influence by environmental factors, however, only scarce data are available on the GH/IGF-system, central physiological system for development and tissue shaping. Most recently, the capability of the host to cope with tissue damage has been postulated as critical for survival. Thus, the present study assessed the combined impacts of estrogens and bacterial infection on the insulin-like growth factors (IGF) and tumor-necrosis factor (TNF)-α. Juvenile rainbow trout were exposed to 2 different concentrations of 17β-estradiol (E2) and infected with Yersinia ruckeri. Gene expressions of IGF-I, IGF-II and TNF-α were measured in liver, head kidney and spleen and all 4 estrogen receptors (ERα1, ERα2, ERβ1 and ERβ2) known in rainbow trout were measured in liver. After 5 weeks of E2 treatment, hepatic up-regulation of ERα1 and ERα2, but down-regulation of ERß1 and ERß2 were observed in those groups receiving E2-enriched food. In liver, the results further indicate a suppressive effect of Yersinia-infection regardless of E2-treatment on day 3, but not of E2-treatment on IGF-I whilst TNF-α gene expression was not influenced by Yersinia-infection but was reduced after 5 weeks of E2-treatment. In spleen, the results show a stimulatory effect of Yersinia-infection, but not of E2-treatment on both, IGF-I and TNF-α gene expressions. In head kidney, E2 strongly suppressed both, IGF-I and TNF-α. To summarise, the treatment effects were tissue- and treatment-specific and point to a relevant role of IGF-I in infection.

Tissue-specific metabolism of benzo[a]pyrene in rainbow trout (Oncorhynchus mykiss): a comparison between the liver and immune organs.

Polycyclic aromatic hydrocarbons (PAHs) are immunotoxicants in fish. In mammals, phase I metabolites are believed to be critically involved in the immunotoxicity of PAHs. This mechanism has been suggested for fish as well. The present study investigates the capacity of immune organs (head kidney, spleen) of rainbow trout, Oncorhynchus mykiss, to metabolize the prototypic PAH, benzo[a]pyrene (BaP). To this end, we analyzed 1) the induction of enzymatic capacity measured as 7-ethoxyresorufin-O-deethylase (EROD) activity in immune organs compared with liver, 2) the organ profiles of BaP metabolites generated in vivo, and 3) rates of microsomal BaP metabolite production in vitro. All measurements were done for control fish and for fish treated with an intraperitoneal injection of 15 mg BaP/kg body weight. In exposed trout, the liver, head kidney, and spleen contained similar levels of BaP, whereas EROD induction differed significantly between the organs, with liver showing the highest induction factor (132.8×), followed by head kidney (38.4×) and spleen (1.4×). Likewise, rates of microsomal metabolite formation experienced the highest induction in the liver of BaP-exposed trout, followed by the head kidney and spleen. Microsomes from control fish displayed tissue-specific differences in metabolite production. In contrast, in BaP-exposed trout, microsomes of all organs produced the potentially immunotoxic BaP-7,8-dihydrodiol as the main metabolite. The findings from this study show that PAHs, like BaP, are distributed into immune organs of fish and provide the first evidence that immune organs possess inducible PAH metabolism leading to in situ production of potentially immunotoxic PAH metabolites.

The teleostean liver as an immunological organ: Intrahepatic immune cells (IHICs) in healthy and benzo[a]pyrene challenged rainbow trout (Oncorhynchus mykiss).

The existence of a resident population of intrahepatic immune cells (IHICs) is well documented for mammalian vertebrates, however, it is uncertain whether IHICs are present in the liver of teleostean fish. In the present study we investigated whether trout liver contains an IHIC population, and if so, what the relative cellular composition of this population is. The results provide clear evidence for the existence of an IHIC population in trout liver, which constitutes 15-29% of the non-hepatocytes in the liver, and with a cellular composition different to that of the blood leukocyte population. We also analyzed the response of IHICs to a non-infectious liver challenge with the hepatotoxic and immunotoxic chemical, benzo[a]pyrene (BaP). Juvenile trout were treated with BaP (25 or 100mg/kgbw) at levels sufficient to induce the molecular pathway of BaP metabolism while not causing pathological and inflammatory liver changes. The IHIC population responded to the BaP treatments in a way that differed from the responses of the leukocyte populations in trout blood and spleen, suggesting that IHICs are an independently regulated immune cell population.

Thyroid signaling in immune organs and cells of the teleost fish rainbow trout (Oncorhynchus mykiss).

Thyroid hormones are involved in modulating the immune system in mammals. In contrast, there is no information on the role played by these hormones in the immune system of teleost fish. Here we provide initial evidence for the presence of active thyroid signaling in immune organs and cells of teleosts. We demonstrate that immune organs (head kidney and spleen) and isolated leukocytes (from head kidney and peripheral blood) of the rainbow trout (Oncorhynchus mykiss) express both thyroid receptor α (THRA) and β (THRB). Absolute mRNA levels of THRA were significantly higher than those of THRB. THRA showed higher expression in immune organs and isolated immune cells compared to the reference organ, liver, while THRB showed the opposite. In vivo exposure of trout to triiodothryronine (T3) or the anti-thyroid agent propylthiouracil (PTU) altered THR expression in immune organs and cells. Effect of T3 and PTU over the relative expression of selected marker genes of immune cell subpopulations was also studied. Treatments changed the relative expression of markers of cytotoxic, helper and total T cells (cd4, cd8a, trb), B lymphocytes (mIgM) and macrophages (csf1r). These findings suggest that the immune system of rainbow trout is responsive to thyroid hormones.

Survival after somatostatin based radiopeptide therapy with (90)Y-DOTATOC vs. (90)Y-DOTATOC plus (177)Lu-DOTATOC in metastasized gastrinoma.

We aimed to explore the effects of (90)Y-DOTATOC and (90)Y-DOTATOC plus (177)Lu-DOTATOC on survival of patients with metastasized gastrinoma. Patients with progressive metastasized gastrinoma were treated with repeated cycles of (90)Y-DOTATOC or with cycles alternating between (90)Y-DOTATOC and (177)Lu-DOTATOC until tumor progression or permanent toxicity. Multivariable Cox regression analyses were used to study predictors of survival. A total of 36 patients were enrolled; 30 patients received (90)Y-DOTATOC (median activity per patient 11.8GBq; range: 6.1-62.2GBq) and 6 patients received (90)Y-DOTATOC plus (177)Lu-DOTATOC (median activity per patient: 14.8GBq; range: 7.4-14.8GBq). Response was found in 26 patients (72.2%), including morphological (n=12, 33.3%), biochemical (n=14, 38.9%) and/or clinical response (n=6, 16.2%). A total of 21 patients (58.3%) experienced hematotoxicity grade 1/2, while 1 patient (2.8%) experienced hematotoxicity grade 3; no grade 4 hematotoxicity occurred. Furthermore, 2 patients (5.6%) developed grade 4 renal toxicity; no grade 5 renal toxicity occurred. Responders had a significantly longer median survival from time of enrollment than non-responders (45.1 months, range: 37.1-53.1 months vs. 12.6 months, range: 11.0-14.2, hazard ratio: 0.12 (0.027-0.52), p=0.005). Additionally, there was a trend towards longer median survival with (90)Y-DOTATOC plus (177)Lu-DOTATOC as compared to (90)Y-DOTATOC alone (60.2 months, range: 19.8-100.6 months vs. 27.0 months, range: 4.0-50.0, hazard ratio: 0.21 (0.01-3.98), p=0.16). Response to (90)Y-DOTATOC and (90)Y-DOTATOC plus (177)Lu-DOTATOC therapy is associated with a longer survival in patients with metastasized gastrinoma. Both treatment regimens are promising tools for management of progressive gastrinoma.

Chiral Templating Activity of Tris(bipyridine)ruthenium(II) Cation in the Design of Three-Dimensional (3D) Optically Active Oxalate-Bridged {[Ru(bpy) 3 ][Cu 2 x Ni 2(1 - x ) (C 2 O 4 ) 3 ]} n (0 ≤ x ≤ 1; bpy = 2,2‘-bipyridine): Structural, Optical, and Magnetic Studies

Three-dimensional oxalate-based {[Ru(bpy)3][Cu2xNi2(1-x)(ox)3]}n (0≤ x ≤ 1, ox = C2O42-, bpy = 2,2‘bipyridine) were synthesized. The structure was determined for x = 1 by X-ray diffraction on single crystal. The compound crystallizes in the cubic space group P4132. It shows a three-dimensional 10-gon 3-connected (10,3) anionic network where copper(II) has an unusual tris(bischelated) environment. X-ray powder diffraction patterns and their Rietveld refinement show that all the compounds along the series are isostructural and single-phased. According to X-ray absorption spectroscopy, copper(II) and nickel(II) have an octahedral environment, respectively elongated and trigonally distorted. As shown by natural circular dichroism, the optically active forms of {[Ru(bpy)3][CuxNi2(1-x)(ox)3]}n are obtained starting from resolved Δ- or Λ-[Ru(bpy)3]2+. The Curie−Weiss temperatures range between −55 (x = 1) and −150 K (x = 0). The antiferromagnetic exchange interaction thus decreases when the copper contents increases in agreement with the crystallographic structure of the compounds and the electronic structure of the metal ions. At low temperature, the compounds exhibit complex long-range ordered magnetic behavior.

Stereochemistry of Amino Acid Spacers Determines the Pharmacokinetics of (111)In-DOTA-Minigastrin Analogues for Targeting the CCK2/Gastrin Receptor.

The metabolic instability and high kidney retention of minigastrin (MG) analogues hamper their suitability for use in peptide-receptor radionuclide therapy of CCK2/gastrin receptor-expressing tumors. High kidney retention has been related to N-terminal glutamic acids and can be substantially reduced by coinjection of polyglutamic acids or gelofusine. The aim of the present study was to investigate the influence of the stereochemistry of the N-terminal amino acid spacer on the enzymatic stability and pharmacokinetics of (111)In-DOTA-(d-Glu)6-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2 ((111)In-PP11-D) and (111)In-DOTA-(l-Glu)6-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2 ((111)In-PP11-L). Using circular dichroism measurements, we demonstrate the important role of secondary structure on the pharmacokinetics of the two MG analogues. The higher in vitro serum stability together with the improved tumor-to-kidney ratio of the (d-Glu)6 congener indicates that this MG analogue might be a good candidate for further clinical study.

Morphological alterations in the liver of yellow perch (Perca flavescens) from a biological mercury hotspot

Mercury (Hg) contamination is a global issue due to its anthropogenic release, long-range transport, and deposition in remote areas. In Kejimkujik National Park and National Historic Site, Nova Scotia, Canada, high concentrations of total mercury (THg) were found in tissues of yellow perch (Perca flavescens). The aim of this study was to evaluate a possible relationship between THg concentrations and the morphology of perch liver as a main site of metal storage and toxicity. Yellow perch were sampled from five lakes known to contain fish representing a wide range in Hg concentrations in fall 2013. The ultrastructure of hepatocytes and the distribution of Hg within the liver parenchyma were analyzed by transmission electron microscopy (TEM) and electron energy loss spectrometry (EELS). The relative area of macrophage aggregates (MAs) in the liver was determined using image analysis software and fluorescence microscopy. No relation between general health indicators (Fulton's condition index) and THg was observed. In line with this, TEM examination of the liver ultrastructure revealed no prominent pathologies related to THg accumulation. However, a morphological parameter that appeared to increase with muscle THg was the relative area of MAs in the liver. The hepatic lysosomes appeared to be enlarged in samples with the highest THg concentrations. Interestingly, EELS analysis revealed that the MAs and hepatic lysosomes contained Hg.

Eosinophilia in Dermatologic Disorders

Eosinophil infiltration can be observed in skin disorders, such as allergic/immunologic, autoimmune, infectious, and neoplastic diseases. Clinical presentations are variable and include eczematous, papular, urticarial, bullous, nodular, and fibrotic lesions; pruritus is a common symptom in all. In this review, we present representative eosinophilic skin diseases according to their clinical pattern, together with histologic findings and diagnostic procedures. We also discuss the potential roles of eosinophils in the pathogenesis of dermatologic disorder. Current pathogenesis-based diagnostic and therapeutic approaches are outlined.

Linking Ah receptor mediated effects of sediments and impacts on fish to key pollutants in the Yangtze Three Gorges Reservoir, China – A comprehensive perspective

The Three Gorges Reservoir (TGR), created in consequence of the Yangtze River's impoundment by the Three Gorges Dam, faces numerous anthropogenic impacts that challenge its unique ecosystem. Organic pollutants, particularly aryl hydrocarbon receptor (AhR) agonists, have been widely detected in the Yangtze River, but only little research was yet done on AhR-mediated activities. Hence, in order to assess effects of organic pollution, with particular focus on AhR-mediated activities, several sites in the TGR area were examined applying the "triad approach". It combines chemical analysis, in vitro, in vivo and in situ investigations to a holistic assessment. Sediments and the benthic fish species Pelteobagrus vachellii were sampled in 2011/2012, respectively, to identify relevant endpoints. Sediment was tested in vitro with the ethoxyresorufin-O-deethylase (EROD) induction assay, and in vivo with the Fish Embryo Toxicity Test and Sediment Contact Assay with Danio rerio. Activities of phase I (EROD) and phase II (glutathione-S-transferase) biotransformation enzymes, pollutant metabolites and histopathological alterations were studied in situ in P. vachellii. EROD induction was tested in vitro and in situ to evaluate possible relationships. Two sites, near Chongqing and Kaixian city, were identified as regional hot-spots and further investigated in 2013. The sediments induced in the in vitro/in vivo bioassays AhR-mediated activities and embryotoxic/teratogenic effects - particularly on the cardiovascular system. These endpoints could be significantly correlated to each other and respective chemical data. However, particle-bound pollutants showed only low bioavailability. The in situ investigations suggested a rather poor condition of P. vachellii, with histopathological alterations in liver and excretory kidney. Fish from Chongqing city exhibited significant hepatic EROD induction and obvious parasitic infestations. The polycyclic aromatic hydrocarbon (PAH) metabolite 1-hydroxypyrene was detected in bile of fish from all sites. All endpoints in combination with the chemical data suggest a pivotal role of PAHs in the observed ecotoxicological impacts.