Tear Mediators in Corneal Ectatic Disorders

PurposeTo compare the concentrations of 11 tear mediators in order to reveal the biochemical difference between pellucid marginal degeneration (PMD) and keratoconus (KC).MethodsWe have designed a cross-sectional study in which patients with corneal ectasia based on slit-lamp biomicroscopy and Pentacam HR (keratometry values (K1, K2, Kmax), astigmatism, minimal radius of curvature (Rmin), corneal thickness (Apex and Min), indices (surface variation, vertical asymmetry, keratoconus, central keratoconus, height asymmetry and decentration)) were enrolled. Eyes of keratoconic patients were similar to the PMD patients in age and severity (K2, Kmax and Rmin). Non-stimulated tear samples were collected from nine eyes of seven PMD patients, 55 eyes of 55 KC patients and 24 eyes of 24 healthy controls. The mediators’ (interleukin -6, -10, chemokine ligand 5, -8, -10, matrix metalloproteinase (MMP) -9, -13, tissue inhibitor of metalloproteinases (TIMP)-1, tissue plasminogen activator, plasminogen activator inhibitor, nerve growth factor) concentrations were measured using Cytometric Bead Array.ResultsMMP-9 was the only mediator which presented relevant variances between the two patient groups (p = 0.005). The ratios of MMP-9 and TIMP-1 were 2.45, 0.40 and 0.23 in PMD, KC and the controls, respectively.ConclusionAs far as we are aware, this is the first study that aims to reveal the biochemical differences between PMD and KC. Further studies of biomarkers to investigate the precise role of these mediators need to be defined, and it is important to confirm the observed changes in a larger study to gain further insights into the molecular alterations in PMD.     

Histamine causes Ca entry via both a storemoperated and a store-independent pathway in bovine adrenal chromaffin cells

The characteristics and properties of the increase in cytosolic [Ca²⁺] that occurs in bovine adrenal medullary chromaffin cells on exposure to histamine have been investigated. Specifically, these experiments were conducted to determine how much external Ca²⁺ enters the cell through a (capacitative) Ca²⁺ entry pathway activated as a consequence of intracellular Ca²⁺ store mobilization, relative to that which enters independently of store depletion via other channels activated by histamine. In Fura-2 loaded cells continued exposure to histamine (10 μM) caused a rapid but transient increase in cytosolic [Ca²⁺] followed by a lower plateau that was sustained as long as external Ca²⁺ was present. In the absence of external Ca²⁺ only the initial brief transient was observed. In cells previously treated with thapsigargin (100 nM) in Ca²⁺-free medium to deplete the internal Ca²⁺ stores, histamine caused no increase in cytosolic [Ca²⁺] when external Ca²⁺ was absent. Re-introduction of external Ca²⁺ to thapsigargin-treated store-depleted cells caused a sustained increase in cytosolic [Ca²⁺] that was further increased (P < 0.0002) upon exposure to histamine. The histamine-evoked increase was prevented by the H₁-receptor antagonist, mepyramine (2 μM). A comparison was made between store-dependent Ca²⁺ entry consequent upon store mobilization with histamine in Ca²⁺-free medium and plateau phase Ca²⁺ entry resulting from stimulation with histamine in Ca²⁺-containing medium. The latter was found to be approximately 3 times greater in magnitude than the former (P ? 0.0001) at the same concentration of histamine (10 μM). It is concluded that histamine causes Ca²⁺ entry not only via a capacitative entry pathway secondary to internal store mobilization, but also causes substantial Ca²⁺ entry through other pathways.     

Epidermal Growth Factor and Basic Fibroblast Growth Factor Protect Dopaminergic Neurons from Glutamate Toxicity in Culture

Abstract: In this report we characterize the toxicity of the excitatory amino acid l -glutamate with respect to dopaminergic neurons cultured from embryonic rat mesencephalon. We also demonstrate that two growth factors, epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF), can protect these neurons from damage. Micromolar concentrations of l -glutamate, as well as agonists that specifically activate N -methyl- d -aspartate (NMDA) and non-NMDA receptors, are all toxic to dopamine neurons in a concentration-dependent manner, as reflected by decreases in high-affinity dopamine uptake and confirmed by decreases in numbers of tyrosine hydroxylase-immunoreactive neurons. Although the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione could attenuate the effects of quisqualate, treatment with this antagonist could not eliminate the effects of glutamate itself. Similarly, (±)-2-amino-5-phosphonopentanoic acid was effective against NMDA toxicity but could not protect cells from quisqualate toxicity. Thus, each type of receptor could mediate neurotoxicity independently of the other. The presence of EGF or bFGF in the culture medium conferred a relative resistance of dopaminergic neurons to glutamate and quisqualate neurotoxicity by increased glutamate transport. However, treatment of the cultures with l - trans -pyrrolidine-2,4-dicarboxylic acid, an inhibitor of glutamate transport, attenuated but did not eliminate the protective effects of both growth factors against glutamate toxicity. When cultures were incubated with conditioned medium from growth factor-treated cultures, neuroprotection was also achieved. These results suggest that both EGF and bFGF can protect neurons from neurotoxicity in culture by increasing the capacity of the culture for glutamate uptake as well as by the secretion of soluble factors into the medium.     

Five new Gc variants detected by isoelectric focusing in agarose gel

Summary Five new genetically determined Gc variants were observed by isoelectric focusing. Seven rare variants 1A4, 1C1, 1C3, 1C9, 1C11, 2A2, and 2A5 were also found in the material comprising Danish ans Swedish paternity cases. All the variants were further analysed by electrophoresis in agarose gel. Two of the new variants had double bands of which the anodal one was susceptible to neuraminidase treatment (Gc 1C13 and 1C14). The three other new variants appeared as a single band, which was unaffected by neuraminidase treatment (Gc 2A9, 2C5, and 2C6). The Gc Ar variant originally detected by electrophoresis was reexamined by isoelectric focusing and named 2C4.     

Cellular localization of somatolactin in the pars intermedia of some teleost fishes

Summary We report here on the cellular localization in the fish pituitary of somatolactin (SL), a putative new pituitary hormone related to growth hormone and prolactin, which has been recently identified in the piscine pituitary gland. Immunocytochemical staining, using anti-cod SL serum, revealed that in the cod pituitary gland, SL is produced by cells in the intermediate lobe, bordering the neural tissue. These cells, staining weakly with periodic-acid-Schiff (PAS), are distinct from the melanocyte stimulating hormone (MSH) cells which, as in all teleosts, are PAS-negative. SL-immunoreactivity was observed in the same location in all other teleost species examined: flounder, rainbow trout, killifish, molly, catfish and eel. In most fish the SL-immunoreactive cells are either strongly or weakly PAS-positive but in rainbow trout are chromophobic, indicating that the SL protein can probably exist in glycosylated and non-glycosylated forms. Thus, in demonstrating the cellular localization of SL, this study provides the first identification of the enigmatic, second cell-type of the fish pars intermedia.     

Transferrin subtypes in 51 Danish patients with hereditary haemochromatosis and in 847 normal subjects

Summary Transferrin (TF) subtypes were determined by isoelectric focusing in 51 unrelated Danish patients with hereditary haemochromatosis (HH) and in 847 normal subjects. The following TF phenotype frequencies were observed in HH patients and controls, respectively: TF*C1, 70.6% vs. 58.8%; TF*C2, 5.9% vs. 2.4%; TF* C3, 0% vs. 0.4%; TF*C1–2, 11.8% vs. 24.7%; TF*C1–3, 5.9% vs. 9.7%; TF*C2–3, 3.9% vs. 2.2%; TF*B–C1, 2.0% vs. 1.5%; TF*B–C2, 0% vs. 0.4%. None of these differences were statistically significant. There was no relationship between the TF subtypes and the clinical or paraclinical expression of disease in HH patients.     

Isolates of Phytophthora cryptogea Pathogenic to Wheat and Some Other Crop Plants

Abstract A fungus of the genus Phytophthora , frequently isolated from diseased spinach roots and also from field-grown wheat plants in an area in the south of Sweden, was identified as P. cryptogea on the basis of morphology, growth characters and cardinal temperatures. Mycelium or zoospores applied as inoculum in a series of pathogenicity tests induced symptoms in spinach, sugarbeet, wheat, cucumber, oil-seed rape, pea and oats. These ranged from death of all (spinach) or some inoculated plants (sugarbeet and wheat), to only slight root symptoms (oats). Successful re-isolations from all plants tested, confirmed infectivity in all cases. This is the first report of the occurrence of P. cryptogea in Sweden and, as far as we know, of pathogenicity of this fungus to wheat, oil-seed rape and oats.     

The diet of feral raccoon dog (<Emphasis Type="Italic">Nyctereutes procyonoides</Emphasis>) and native badger (<Emphasis Type="Italic">Meles meles</Emphasis>) and red fox (<Emphasis Type="Italic">Vulpes vulpes</Emphasis>) in Denmark

The raccoon dog (Nyctereutes procyonoides) is an East Asian Canid that has been introduced in Europe. Introduction of alien species is an increasing conservation issue. We examined the diet of a recently established raccoon dog population in Denmark by analysing stomach content in 249 carcasses collected in 2008–2016. Raccoon dog diet was compared to the diet of native badger (Meles meles) and red fox (Vulpes vulpes) in Denmark. The most common food for raccoon dogs were invertebrates (frequency of occurrence, FO 69%), small mammals (FO 68%), birds (FO 41%), fruits (FO 38%), amphibians (FO 36%) and carrions (FO 34%). The occurrence of invertebrates was highest during spring and summer, while fruits, cereals and carrions were eaten most often during autumn and winter. As expected, raccoon dog shared the major food categories with badger and red fox, but generally, it had a wider dietary niche. Overall, dietary overlap between raccoon dog and badger was 0.74 (Pianka index, O_jk). The dietary overlap with red fox was relatively high in all seasons, peaking in summer (O_jk 0.87) and dropping in winter (O_jk 0.79). Despite the dietary overlap between the alien racoon dog and native red fox and badger, the species may coexist due to partitioning of feeding habitats and/or because the red fox is limited by other factors, e.g. diseases and anthropogenic activities. The introduced raccoon dog seems to fit a dietary niche between badger and red foxes in human-dominated landscapes in north-western Europe.     

Identification of a new serum protein polymorphism as transferrin

Summary By isoelectric focusing at pH 3.5–9.5, Kühnl and Spielmann (1977) recently demonstrated a new genetically determined serum protein polymorphism designated Hp^a because of an apparently specific reaction with antihaptoglobin. In this study the polymorphism was reproduced, but the components were found to focus at pH 5.8, which is different from the pI of haptoglobin, and immunologic relation to haptoglobin could not be comfirmed. Using pure transferrin as a reference, the results of isoelectric focusing, crossed immunoelectrophoresis, and immunofixation indicated that the polymorphic components were identical to transferrin. This polymorphism does not correspond to the already known transferrin polymorphism, as the two usual genes, tentatively designated Tf¹ and Tf², in my population sample (n=132) were 0.19 and 0.81, and, further, all individuals except three in the sample belong to type Tf-C.     

Structure, enzymatic stability and antitumor activity of sea lamprey GnRH-III and its dimer derivatives

Direct antitumor activity of sea lamprey (Petromyzon marinus) gonadotropin-releasing hormone III (Glp-His-Trp-Ser-His-Asp-Trp-Lys-Pro-Gly-NH(2); lGnRH-III) was described on several tumor cells. To improve the selectivity of antitumor effects without increasing the hormone releasing activity and to enhance the enzymatic stability, lGnRH-III dimers were prepared via disulfide bond formation. Our results demonstrate that the lGnRH-III dimer derivatives exhibited higher antiproliferative effect and enzymatic stability in comparison with the native lGnRH-III, while lower LH-releasing potency was determined. In order to find a correlation between the biological and structural features of these compounds, the conformation of lGnRH-III and its dimer derivatives was determined by ECD, VCD, FT-IR and (1)H NMR.