Insulin-like and insulin-inhibitory effects of monoclonal antibodies for different epitopes on the human insulin receptor

Monoclonal antibodies previously shown to react with five distinct epitopes on the human insulin receptor were tested for their metabolic effects on isolated human adipocytes. Two antibodies which reacted with receptor alpha-subunit and completely inhibited 125I-insulin binding mimicked the actions of insulin to stimulate lipogenesis from [14C]glucose and to inhibit catecholamine-induced lipolysis. On a molar basis, these antibodies were comparable in potency with insulin itself. Two other antibodies which decreased insulin binding only slightly or not at all also mimicked these metabolic effects of insulin. One of these antibodies reacted with receptor beta-subunit. In contrast, a further antibody which reacted with alpha-subunit and inhibited insulin binding did not affect basal lipogenesis or catecholamine-induced lipolysis, but was able to antagonize the effects of insulin on these processes. The same antibody antagonized the insulin-like effect of another antibody with which it competed in binding to insulin receptor, but not the effect of an antibody which bound independently to the receptor. It is concluded that binding of ligand at or close to the insulin-binding site is neither necessary nor sufficient to trigger insulin-like metabolic effects, which may rather depend on some general property of antibodies, such as their ability to cross-link and aggregate receptor molecules.

Uveitis and arthritis induced by systemic injection of streptococcal cell walls

A single injection of an aqueous suspension of group A streptococcal peptidoglycan-polysaccharide complexes (PG-PS) when injected intraperitoneally into Lewis rats induced a self-limiting bilateral uveitis with associated perpetuating polyarthritis. The uveitis was characterized clinically during the first 72 h by iritis and fibrin deposition. Acutely, there was infiltration of polymorphonuclear cells. The symptoms gradually subsided, and at the close of the experiment eyes were normally clinically and histologically. In contrast, perpetuating inflammation and severe tissue injury developed in the limb. Using an enzyme immunoassay with specificity for the group A streptococcal polysaccharide, the levels of PG-PS in tissues of animals that were killed 1 to 7 days post-injection were measured. The relative amounts of antigen in eye:limb:liver of PG-PS injected animals were 1:9:170. The differences in the amounts of antigen detected in the eye and limb may help explain the development of the acute uveitis in contrast to the perpetuating polyarthritis observed on PG-PS administration. The authors suggest that bacterial debris may act similarly in causing ocular inflammation in man.

Relationship between private self-consciousness and anxiety scores in threatening situations

The present study explored the hypothesis that, when facing a threatening situation persons high in dispositional self-focus will exhibit higher state-anxiety than persons low in dispositional self-focus. It was predicted that dispositional self-focus is positively correlated with trait-anxiety and in a threatening situation is associated with increased ‘worry.’ The relation between the experience of anxiety and the direction of attention was investigated using the private self-consciousness subscale as a measure of dispositional self-focus. 64 undergraduate male and female students scored high on a measure of state-anxiety prior to a course examination. Women had significantly higher state-anxiety scores than men. Significant correlations were found for private self-consciousness with state-anxiety, trait-anxiety, and ‘worry.’ These results are discussed in relation to the experience of anxiety.

Epstein-Barr virus binding to virus-carrying cell lines is enhanced in the presence of C3 and C3d

The relationship between the receptors for the Epstein-Barr virus (EBV) and the C3d fragment of complement was investigated at the molecular level. In the presence of cell-bound C3, virus binding was enhanced in EBV genome-carrying lines. An identical effect could be elicited by C3d at one-quarter the weight amount; C3b and methylamine-treated C3 had no effect on virus binding. The minimum concentration of C3 which produced significant enhancement was 25 micrograms/ml. Virus binding increases were observed only after 20 min of complement-cell co-incubation. The response was not noted with EBV-negative lines and was independent of virus strain assayed (B95-8 and P3HR-1). These studies suggest that the binding sites for the two moieties are distinct, although they both involve the same cell surface complex. The two receptors are believed to display cooperativity.

Hydroptila Dalman and Orthotrichia Eaton (Trichoptera: Hydroptilidae) from the islands of New Guinea and New Britain, with Observations on Relationships

Nine new species of Hydroptila and fourteen of Orthotrichia are described from the islands of New Guinea and New Britain. and new records are given from this region for three previously known species, Hydroptila bispina Kimmins (New Guinea), H. triloba Kimmins (Guadalcanal I.) and H. incertula Mosely (north-eastern Australia). Keys to adult males of all New Guinea species in the two genera are provided and relationships of species are discussed.

The effects of sodium orthovanadate, noradrenaline and angiotensin II on isolated perfused rat kidney glomerular-tuft diameter

The effects of sodium orthovanadate, angiotensin II (A II) and noradrenaline (NA) were studied on the isolated perfused rat kidney (IPRK) and on the diameter of the glomerular capsule and tuft. Vanadate (4.5 microM), A II (20 nM) and NA (17.3 microM) increased the total resistance of the IPRK. There was a simultaneous increase in glomerular filtration rate with vanadate and A II, but a decrease with NA. The glomerular tuft/capsule diameter ratio decreased significantly from 0.85 (control) to 0.81, 0.81 and 0.78 for vanadate, A II, and NE treated kidneys, respectively. The decrease in ratio was associated with an increase in diameter of the glomerular capsule for A II and NE. This finding accompanied with simultaneous rise in TPR and GFR in the case of vanadate and A II, indicates that the post capillary efferent arteriolar vasoconstriction is a component in the mechanism of action with A II and vanadate. Evidence for such a component is less clear for NA because GFR decreases and TPR increases. Vanadate may affect both with a predominance on the efferent arteriole. The data indicate that histological measurements of glomerular size lead to a better understanding of the mechanisms of vasoactive drugs acting on the kidney.

The Epstein-Barr virus receptor is distinct from the C3 receptor

Polyvalent serum directed against C3 receptors was employed in an attempt to block Epstein-Barr virus (EBV) binding to virus receptor-containing cell lines. The serum eliminated 90% of virus binding to Daudi and BJAB, lines which express only the C3d receptor. Raji and Ramos cells, which express the C3d, C3b and C3bi receptors, still adsorbed 70% of their virus capacity in the presence of excess antiserum. These effects were independent of the virus strain. In the light of previous reports, these data imply that, although the two receptors, EBV and C3d, are closely associated, the binding sites of EBV and complement are distinct. Additionally, an unusual EBV substrain-specific receptor found on U698 and P3HR-1/ASNP lines was shown to be independent of complement receptors.

New Species in the Australian Hydroptilidae (Trichoptera), with Observations on Relationships and Distributions

Seventeen new species are described in five genera of Australian Hydroptilidae, bringing the total number now known to 97. Interest in the new species centres particularly on the extension of the distribution of the genus Maydenoptila to include south-west Western Australia and on the addition of five species to the highly divergent aberrans-group in Orthotrichia. Further new species are referred to Hellyethira, Orphninotrichia, Mulgravia and to other species-groups in Orthotrichia.

Quantitative comparison of Epstein-Barr virus receptor expression on sIgM and sIgG cell lines and B-cell lymphoma biopsies

Over 50 B-cell derived lines and B-cell lymphoma and leukemia biopsies were screened for expression of the Epstein-Barr virus (EBV) receptor. The 13 sIgM-positive lines bound more than five times as much virus as the six IgG lines. Among the biopsies, the 17 sIgM, 11 sIgM and sIgD, and seven sIgG expressing biopsies were further divided according to expression of the C3 receptor. C3 receptor-positive biopsies, which expressed sIgM alone or along with sIgD, had the largest subpopulation of cells which expressed the EBV receptor (EBVR). C3 receptor-negative biopsies only expressed the EBVR on half as many cells as their C3 receptor-positive counterparts. However, the relative number of EBVR on individual EBVR-positive cells was independent of C3 receptor expression. Within the sIgG class, both C3 receptor-negative and positive cells expressed equally low levels of EBVR, both in terms of subpopulation and relative number of EBVR per positive cell. These results suggest that subpopulation expression of the EBV receptor is related to the C3 receptor but that relative number of receptors per cell is associated with sIg phenotype.

Tricholeiochiton Kloet & Hincks and Hew Genera in the Australian Hydroptilidae

The west Palearctic-Southeast Asian genus Tricholeiochiton is newly recorded from Australia with descriptions of four species; the generic diagnosis is revised and a key given to Australian species. The number of endemic genera in the Australian Hydroptilidae is increased to eight, with the erection of four new genera to accommodate seven problematical species: the relationships of the endemics are discussed.

Two large virion envelope glycoproteins mediate Epstein-Barr virus binding to receptor-positive cells

The four major Epstein-Barr virion envelope components were separated by column chromatography and reconstituted into artificial liposomes. These liposomes were tested for their ability to bind selectively to Epstein-Barr virus receptor-positive cells. Only when the two high-molecular-weight glycoproteins, VE1 and VE2, were present together was a stable binding complex formed. The addition of the other virion envelope components did not increase the levels of binding. This binding was inhibited by unlabeled viable virions and by neutralizing antisera, which recognized the two components. Adsorption of viable virus was also eliminated by the antisera. The enzyme susceptibility pattern of the cell-liposome interaction is similar to that of the virus-cell interaction, thus confirming the specificity of the binding site. A model for Epstein-Barr virus binding in which VE1 and VE2 coordinately recognize the same binding site is presented.

A microassay for quantitatively detecting the Epstein-Barr virus receptor on single cells utilizing flow cytometry

A quantitative microassay for detecting and analyzing the Epstein-Barr virus receptor (EBVR) utilizing fluorescein-conjugated virions is presented. The test is virus substrain-specific. Both the B95-8 and P3HR-1 strains were labelled and adsorbed to a variety of targets. Relative binding of virus was assessed by flow cytometry, the results being directly comparable with those obtained by earlier methods. Cell size and cellular DNA content were measured simultaneously with virus binding, thus enabling us to calculate EBVR density and to correlate receptor synthesis and cell cycle stage.

The detection of Epstein-Barr virus receptors utilizing radiolabelled virus

Epstein-Barr virus (EBV) was labelled with 3H-thymidine and purified about 1000-fold from the culture medium by ultracentrifugation on 5 to 30% dextran gradients. The presence of the virus was monitored by radioactivity and Epstein-Barr virus-determined nuclear antigen (EBNA) induction in sensitive indicator cells (Ramos). Peaks for both activities occurred in the 17 to 18% dextran fractions. Unlabelled virus recovered in the peak fraction was labelled with 125I. Both thymidine and 125I-labelled purified virus bound quantitatively to receptor-positive Burkitt lymphoma-derived cell lines but not to EBV-receptor-negative T-lymphocyte-derived cell lines. Thymidine-labelled virus that was allowed to bind to Raji cells was present in the interior of briefly trypsinized cells after 3 h incubation at 37 degrees C. The results provide a convenient method for detecting the EBV receptor by radioactively labelled virus.

Difference in viral binding between two Epstein-Barr virus substrains to a spectrum of receptor-positive target cells

Radio-labelled Epstein-Barr virus (EBV) was utilized in a direct binding assay to detect the presence of EBV receptors. The sensitivity of this method was affirmed by the detection of EBV-receptors on three EV-carrying cell lines that have previously been reported as receptor negative. Two laboratory substrains of EBV, derived from the cell lines B95-8 and P3HR-I (designated B and P virus respectively), were tested in the binding assay. The main repcptor prototype adsorbed both viral strains without apparent distinction. In contrast, two lines, a Swedish EBV-negative B-cell lymphoma (U698) and a virus non-producer subline of the receptor-negative P3HR-1 line, adsorbed P virus selectively but failed to adsorb B virus.

Epstein-Barr virus receptor expression is correlated to cell cycle phase

Epstein-Barr virus (EBV) receptor positive cells absorbed FITC-conjugated virions and were subsequently stained for DNA content with propidium iodide. These cells were analyzed by flow cytometry to determine the relationship between cell cycle and EBV receptor (EBVR) expression on single cells. EBVR was present throughout the entire cell cycle. The level of expression, however, varied; increasing in G1 and G2/M while remaining approximately constant in S phase. Analysis of receptor density in terms of cell size demonstrated that smaller cells, in early G1, have a greater density of receptors per unit membrane than larger G2/M and S phase cells.

Cell surface glycoprotein patterns of two EBV-negative lines and their EBV converted sublines

Cell surface galactosyl-glycoprotein patterns were compared between Ramos and BJAB, two Epstein-Barr virus (EBV)-negative Burkitt lymphoma lines, and their acutely EBV-superinfected and stably EBV-converted derivatives. A major difference between Ramos and its EBV-infected variants was the appearance of a 69,000 mol. wt. galactosyl-glycoprotein (GP69) in the latter. The same phenomenon was found in BJAB along with the additional appearance of a 71,000 mol. wt. galactosyl-glycoprotein (GP71) in the EBV-infected cells. GP71 was present in Ramos and in its EBV-converted derivatives.

The Genera Oxyethira Eaton, Gnathotrichia Ulmer and Stemoxyethira Kimmins (Trichoptera:Hydroptilidae) in Australia

The number of non-endemic genera in the Australian Hydroptilidae is raised to five with the recognition of Oxyethira Eaton, in which four new species are described, and the referral of species to Gnathotrichia Ulmer and Stenoxyethira Eaton. The discovery of Gnathotrichia and Stenoxyethira is significant as evidence of Oriental affinities within the Australian Hydroptilidae; their taxonomic status is examined. A key to males of Australian Oxyethira is provided.

Effects of sighs and different tidal volumes on compliance, functional residual capacity and arterial oxygen tension in normal and hypoxemic dogs

In order to assess the usefulness of sighs in preventing deterioration of arterial PO2 (PaO2), functional residual capacity (FRC), and compliance in hypoxemic patients, the authors studied 20 anesthetized and paralyzed dogs. The dogs were ventilated with either normal (11.5 ml/kg) or large (23 ml/kg) tidal volumes and their lungs were either normal or made edematous with oleic acid injection. Sighs (46 ml/kg) were administered periodically and PaO2, FRC, and compliance were measured at intervals between sighs. In dogs with normal lungs, regardless of tidal volume, sighs produced a transient increase in compliance and FRC but PaO2 was not significantly affected. In dogs with pulmonary edema, sighs produced inconsistent effects on FRC and compliance and, interestingly, PaO2 decreased after the sighs may be unnecessary in patients with pulmonary edema, especially when they are already receiving large tidal volumes.

A placebo-controlled trial of ketotifen (HC 20-511, Sandoz) in allergen induced asthma and comparison with disodium cromoglycate

Ketotifen failed to protect against cat fur allergen induced asthma in a double blind placebo-controlled trial in ten asthmatic children. Disodium cromoglycate gave effective protection against the immediate and the late asthmatic reactions but there were no significant differences between the effects of ketotifen and a placebo.

A review of the Australian genera Xuthotrichia Mosely and Hellyethira Neboiss decriptions of new species

The taxonomy of the Australian genus Xuthotrichia Mosely is examined, and three of the four known species are transferred to Hellyethira Neboiss. Twelve new species of Hellyvethira are described, bringing the total to 15, with females included for seven. A key to adult males is provided.

The Australian species of Orthotrichia Eaton (Trichoptera : Hydroptilidae)

The genus Orthotrichia Eaton. newly recognized from Australia, is represented here by 25 species of diverse structure, arranged in four species-groups based primarily upon the male genitalia. Twenty-four of the species are new while the remaining one is transferred to Orthotrichia from the monotypic Targa- trichia Neboiss, which is thus synonymized. The scope and diagnoses of Orthotrichia and some other hydroptilid genera are discussed briefly, with special reference to the relative importance of wing and genitalic characters.

A review of the Australian specieso of Hydroptila Dalma (Trichoptera : Hydroptilidae) with descriptions of the new species

The taxonomy of Hydroptila Dalman in Australia is examined. The four known species are reviewed and females of three of them described for the first time. Descriptions of five new species are given, with male and female for four and male only for the fifth. A key to adults is provided.

Noise, vitamin A deficiency, and emotional behavior in rats

This study investigated the effects of aversive stimulation (loud noise) on the emotionality of rats which were food-deprived, satiated, or vitamin A deficient. Activity (number of squares traversed in an open-field task) and defecation scores comprised the measures of emotion. Significantly more boli were recorded for food-deprived Ss than satiated Ss, while the number of boli for vitamin A deficient Ss was in between. Noise significantly increased the number of boli for all groups. Deprivation conditions, noise-no noise, and the interaction of these variables were all significant on activity scores. Food-deprived Ss were the most active, satiated Ss the least active, and again vitamin A deficient Ss fell in between. Groups were more active with noise. The significant interaction probably resulted from the marked increase in activity by deprived Ss under noise. Thus, aversive stimulation may have greater effect on animals already under stress from food deprivation than on satiated animals.