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The leafhoppers comprise by far the largest family within the Hemiptera, with approximately 19,500 described species in over 40 subfamilies (Oman et al. 1990) of which the subfamily Cicadellinae comprises around 2,400 species in around 330 genera. The name “sharpshooter” for this group of xylemfeeding leafhoppers has increasingly been used especially in the USA. They are among the largest and most brightly coloured of the leafhoppers. Some species are important vectors of the xylem-limited bacterium Xylella fastidiosa, which affects both citrus trees in Brazil as well as grapevines in southern USA. The Cicadellinae, as currently defined, was revised by David Young (1915–1991) in three remarkable volumes (Young 1968a, 1977a, 1986a). The publication of these works has enabled the evaluation and description of additional genera and species, primarily by researchers in Brazil and China. The availability of these taxonomic monographs and subsequent publications has made the Cicadellinae a relatively well-known group. In 2004 a project was started, funded by UK-based Leverhulme Trust, which has enabled a compilation of digital images of Cicadellinae. This paper is a brief review of the project in the context of the history of taxonomic work on this group of leafhoppers over the past 150 years. Abbreviations for Institutions discussed in text BMNH The Natural History Museum, London, UK HNHM Hungarian Museum of Natural History, Budapest, Hungary MMBC Brno, Czech Republic MNHN Museum National d’Histoire Naturelle, Paris, France NCSU North Carolina State University Insect Collection, Raleigh, North Carolina, USA NHRS Naturhistoriska riksmuseet, Stockholm, Sweden NMW Naturhistorisches Museum Wien, Vienna, Austria USNM National Museum of Natural History, [formerly, United States National Museum], Washington, DC, USA ZMHB Museum fur Naturkunde der HumboldtUniversitat, Berlin, Germany

Leptin is secreted by adipose tissue and thought to regulate appetite at the central level. Several studies have explored the central nervous system (CNS) entry of this peptide across the blood-brain and blood-cerebrospinal fluid (CSF) barriers in parallel, but this is the first to explore the transport kinetics of leptin across the choroid plexus (blood-CSF barrier) in isolation from the blood-brain barrier (BBB). This is important as the presence of both barriers can lead to ambiguous results from transport studies. The model used was the isolated Ringer perfused sheep choroid plexus. The steady-state extraction of [(125)I]leptin (7.5 pmol l(-1)) at the blood face of the choroid plexus was 21.1+/-5.7%, which was greater than extraction of the extracellular marker, giving a net cellular uptake for [(125)I]leptin (14.0+/-3.7%). In addition, trichloroacetic acid precipitable [(125)I] was detected in newly formed CSF, indicating intact protein transfer across the blood-CSF barrier. Human plasma concentrations of leptin are reported to be 0.5 nM. Experiments using 0.5 nM leptin in the Ringer produced a concentration of leptin in the CSF of 12 pM (similar to that measured in humans). [(125)I]Leptin uptake at the blood-plexus interface using the single-circulation paired tracer dilution technique (uptake in60 s) indicated the presence of a saturable transport system, which followed Michaelis-Menten-type kinetics (K(m)=16.3+/-1.8 nM, V(max)=41.2+/-1.4 pmol min(-1) g(-1)), and a non-saturable component (K(d)=0.065+/-0.002 ml min(-1) g(-1)). In addition, secretion of new CSF by the choroid plexuses was significantly decreased with leptin present. This study indicates that leptin transport at the blood-CSF barrier is via saturable and non-saturable mechanisms and that the choroid plexus is involved in the regulation of leptin availability to the brain.

The positive outcomes of drinking citrus juice, as well as the biological responses to specific nutrients found in juice, have been researched extensively. This chapter summarizes the role citrus juice plays in providing important nutrients and bioactive compounds to the diet. It also summarizes the relationship of these components to various health benefits.

Poor foetal and neonatal nutrition may impair normal pancreatic β -cell development and predispose to diabetes in later life. We investigate here the nature of the pancreatic β -cell dysfunction in sucrose-fed adult offspring malnourished during the foetal-neonatal period and examine glucose metabolism and the generation of signals involved in the secretory mechanism. In islets from sucrose-fed previously malnourished rats, rates of glucose utilisation (production of 3 H 2 O) and oxidation (production of 14 CO 2 ), at 2, 6 and 10 mM glucose, were not lower than those of controls. ATP concentrations in islets from previously malnourished rats fed sucrose at 2 and 10 mM glucose were similar to those of controls. Glucose-stimulated insulin release was impaired (by 49–55%) in islets from these animals as was the response to keto-isocaproate (by 70%) and tolbutamide (by 70%). Under conditions in which ATP-sensitive K + channels were clamped open (40 mM K + and diazoxide), glucose-stimulated insulin release in islets from previously malnourished rats fed sucrose was reduced. These findings show that defects in insulin secretion in islets isolated from previously malnourished animals are located in both ATP-sensitive K + channel dependent and independent pathways. They do not involve alterations in the early steps of glucose handling in the β -cell, including glucose metabolism and ATP generation.

To test the hypothesis that poor foetal–neonatal nutrition predisposes adult animals to impaired glucose tolerance or diabetes, pregnant and lactating rats were fed a low (5%) protein diet and glucose tolerance and pancreatic islet function then assessed in the adult offspring. To expose any underlying defects the offspring were allowed access to a sucrose supplement (35%) or fed a high fat diet. Offspring born to low protein-fed females had significantly lower body weights than controls. In islets from previously malnourished rats, insulin release in batch incubations or perifusion was not significantly different to controls. In islets from previously malnourished animals fed sucrose, glucose-stimulated insulin release was reduced in perifusion by 66% (PPPPP Journal of Endocrinology (1997) 154, 177–185

We fed normal rats a high sucrose diet in order to test the hypothesis that mild hyperglycemia can induce defects in pancreatic beta-cell function and impair glucose-stimulated insulin release. Rats provided with free access to a sucrose solution (35%) voluntarily consumed 50% more carbohydrate than control per day. After 7 days of sucrose feeding, glucose tolerance was significantly impaired; the area under the glucose tolerance test curve (GTT) was 683 +/- 61 mmol/120 min compared with 472 +/- 56 mmol/120 min in controls (P0.05). Impaired glucose tolerance was still present after a further 12 days (area under the GTT: 749 +/- 99 mmol/120 min). Sucrose-fed rats were significantly (P0.05) hyperglycemic by 1.5 mmol/l over controls. When insulin secretion was assessed in vivo and in vitro in control and sucrose-fed rats, no significant differences were apparent in plasma samples collected over a 1-h period or in statically incubated or perifused isolated pancreatic islets. In addition, the rates of glucose utilisation and oxidation were normal in islets from sucrose-fed rats. These data do not support the hypothesis that minimal hyperglycemia is sufficient to impair glucose-stimulated insulin release.

Summary Extracts of cotton dust were tested for their ability to activate the alternative complement pathway in fresh normal human serum (NHS). Alternative pathway activation was determined by a haemolytic assay utilizing glutathione-sensitized human erythrocytes, consumption of alternative pathway components in terms of alternative pathway CH50 units and an immunoelectrophoretic assay to detect split products of activation of factor B. All assays were performed under conditions that have been shown to block the initial steps of classical pathway activation but permit activation of the alternative complement pathway. Results demonstrate that the cotton dust extracts could consume alternative complement pathway proteins in a dose-response manner. The complement activating factor is probably endotoxin since a cotton dust extract obtained by an extraction method for endotoxin yielded the greatest activity.

1 Temperate woodland canopy as a habitat for insects is discussed. 2 A general account is given of the Typhlocybinae as the mesophyll-feeding guild of canopy feeders. 3 Three sampling sites in South Wales are described, from which adult leaf-hoppers were sampled regularly from twelve species of trees during 1974. 4 Rearing records, based on the sampling of last instar nymphs and subsequent rearing of adults, are given. 5 Over 20 000 adult insects of thirty-five identified species were taken during 1974. 6 Results are analysed to compare species associations with different tree species. Most leaf-hoppers show very distinct specific plant-dependent distributions within the canopy. Many are dominantly associated with only one host plant. Others show more complicated patterns of associations. Only one species was found on all trees sampled. 7 The patterns of leafhopper distributions in woodland canopy are compared with previously described grassland habitats. The relative permanence and size of trees may be important factors. 8 Examples of groups of ecologically similar species coexisting together are discussed.

The role of female oviposition behaviour in determining the food plant preferences of phytophagous insects observed in the field is reviewed. Complex patterns of food plant relationships in leafhoppers associated with trees in Britain are discussed. Some species are polyphagous, others are oligophagous and most are monophagous. Experiments on feeding of nymphs and oviposition behaviour of adult leafhoppers give little support for theories which invoke the nymphal conditioning of food preferences and adult oviposition. Distinctive patterns of oviposition behaviour are important factors in the ecology and evolution of these insects. RESUME LE COMPORTEMENT DE PONTE, FACTEUR ECOLOGIQUE CHEZ LES CICADELLES DES SOMMETS DES ARBRES Lors de la ponte, les insectes phytophages font generalement une distinction entre les differentes plantes qui s'offrent a eux sur le terrain. Les cicadelles associees aux arbres ont souvent des systemes de ponte specifiques sur leur plantes-hotes. Des experiences avec les cicadelles oligophages se nourrissant de mesophylle, Aguriahana stellulata, Edwardsiana rosae, Lindbergina aurovittata et Ribautiana tenerrima, et les monophages R. scalaris et R. ulmi montrent que les nymphes de toutes ces especes peuvent se nourrir et survivre sur des especes vegetales plus nombreuses que celles sur lesquelles on les trouve sur le terrain. Les nymphes de R. ulmi ont montre une preference marquee pour les feuilles de Carpinus lorsqu'elles leur ont ete presentees avec celles de leur hote habituel, Ulmus, dans des conditions experimentales. Il n'y a pas de preuve que la nourriture absorbee par les nymphes les conditionnent quant a leurs preferences alimentaires on leurs preferences de ponte ulterieures. On en conclut que les comportements de ponte hereditaires, chez les cicadelles et chez beaucoup d'autres insectes phytophages, sont importants dans l'ecologie et dans l'evolution des interactions insecte/plante-hote.

1. The male songs of two of the commonest cicadas in southern France are described with oscillograms. 2. Males of Cicada orni L. aggregate during calling whilst those of Lyristes plebeius (Scop.) space themselves out. 3. Both species are widely polyphagous on trees and shrubs, but L. plebeius sings from thinner stems than does C. orni 4. Such behaviour may result in the spatial separation of different species in the same habitat.

Antigenic relationships among three species of Aspergillus (A. fumigatus, A. glaucus, and A. flavus) were examined by paired cross-radioallergosorbent test (RAST) inhibition analysis, an in vitro technique based on human IgE antibody specificity. Alternaria tenuis was found to be antigenically unrelated to each of the three species of Aspergillus and was used as a negative control. A single test serum yielded uninhibited RAST indices of 6, 7.4, 8.1, and 7.8 for A. fumigatus, A. glaucus, A. flavus, and Alternaria tenuis, respectively. At a concentration of 10 mg/ml, A. fumigatus inhibited A. glaucus RAST by 63% and A. flavus RAST by 62%. A. glaucus inhibited A. fumigatus RAST by 36% and A. flavus RAST by 63%. A. flavus inhibited A. fumigatus RAST by 44% and A. glaucus RAST by 81%. Each species of Aspergillus produced significant but only partial inhibition of RAST to each of the other two species analyzed. Results indicate the existence of both shared and unique antigens among these three species of Aspergillus. Paired cross-RAST inhibition may be used as an approach to study species relationships among genera of several classes of clinically relevant fungi. Unless many strains are employed, data obtained do not represent a definitive analysis of species, because of possible different degrees of inhibition by various strains of a particular species. They do, however, allow for the antigenic comparison of two or more crude, poorly characterized preparations thought to be important in human allergic disease.

Cryoproteins were isolated from the serum of 5 patients with essential cryoglobulinaemia 5 patients with rheumatoid arthritis, and 2 patients with Sjøgren's syndrome. These cryoprecipitates contained IgG, IgM, and IgA as well as complement proteins C1q, C4, C3, and factor B. The cryoprecipitates were analysed further for content of antibody and antigen, and were tested for their ability to activate complement. In the cryoprecipitates of 2 patients with Sjøgren's syndrome, nuclear antigen and antinuclear antibody characteristic of an immunological specificity found in Sjøgren's syndrome were shown. The cryoprecipitates of 6 other patients contained rheumatoid factor and antibody to a lymphocyte nuclear antigen. The solubilized cryoprecipitates were tested by in vitro assays for their ability to activate complement by the classical or alternative pathways. All 12 cryoprecipitates activated the classical pathway. 9 of the 12 cryoprecipitates also activated the alternative complement pathway under conditions which did not involve activation of C1 and C4. These studies show that a high percentage of cryoprecipitates consist at least in part of immune reactants. We discuss the relationship of these findings to pathogenetic mechanisms in disease.

Numicia gauhati sp.n., collected from rice in Assam, India, is described and illustrated. It is compared with other known species of Numicia from the Oriental Region. N. maculosa pusana Ghauri is raised to specific status.

1. Field host plants of the six British species of Oncopsis are described. O. avellanae is unusual in being associated with both Corylus and Alnus. 2. Laboratory experiments on nymphal feeding preferences, nymphal and adult survival, and adult oviposition preferences are described for all species, using Carpinus, Corylus, Alnus and Betula species as test plants. 3. All experiments demonstrated considerable specificity in feeding, and especially oviposition. 4. It is suggested that discriminative oviposition behaviour is the major determinant of observed field distribution patterns.

The natural vegetation of southern Saskatchewan prior to settlement has been reconstructed from 2500 township plats compiled during the Dominion Lands Survey of the 1880's. The north–south section lines within each township were used as transects from which percent cover of grassland, woodland, scrub, brulé, marsh, and open water was calculated and compiled in map form. Although directly comparable modern data are not available, it is concluded that woodland areas have increased over the last 80 or 90 years.

1. Sixty-two British species of Typhlocybine leafhoppers are known to feed on the leaf-mesophyll tissue of trees and shrubs. British host records for fifty-five of these are given. 2. The leafhopper faunas of thirty-six species of native and introduced trees and shrubs are described. 3. The Shannon-Wiener equation was used to calculate species diversity for adult samples collected from twenty different species at sixteen different localities in Wales, southern England and northern Scotland. 4. Sorensen's coefficients were calculated for rearing data from Britain generally, and subjected to cluster analysis. Most trees have low similarities with respect to leafhopper faunas and are quite distinct. Taxonomic relationships of trees appear to be relatively unimportant in determining the similarities of their leaf-hopper faunas. 5. Using the same data, species—area relationships were calculated for thirty-four different tree and shrub species and their associated leaf-hoppers. A significant regression was obtained, but it explained only 16% of the variation. It is thus suggested that host plant range is relatively unimportant in determining the numbers of these species associated with different trees in Britain. 6. Some introduced species of trees, particularly the recently planted Nothofagus, have acquired large leafhopper faunas.

Animals sensitized by intratracheal administration of particulate Micropolyspora faeni antigen and subsequently challenged with the antigen intratracheally developed lesions of hypersensitivity pneumonitis histologically similar to those observed in man wih this disease. Animals sensitized with antigen but depleted of complement with cobra venom factor prior to challenge with the antigen manifested a significant reduction in mean lesion indices when compared to a group of control animals that were not complement-depleted. These data indicate that complement is necessary for the development of pulmonary lesions of experimental hypersensitivity pneumonitis in the rabbit.

1. 239 species of leafmining insects have been recorded from thirty-seven species of trees and large shrubs in Britain. 2. A significant species—area relationship was obtained for these insects, but it explained only 19% of the variation about the regression he. A further 23% of the variation may be accounted for by taxonomic relationship of host plants. 3. A significant correlation was established between the number of species of leafminers and those of mesophyll-feeding leafhoppers for twentyeight host tree species. Both guilds are dominated by host specific feeders. 4. It is suggested that species—area effects are important in determining species richness of phytophagous insects mainly when groups of closely related host plants are considered. With more diverse arrays of hosts, taxonomic influences, which are probably mainly chemical, may outweigh such area related effects.

Unique hypertrophic apocrine sweat glands are described in the neck, perineal and inguinal skin of mink kits. These glands enlarge after birth, only to regress rapidly and become vestigal by weaning. No similar phenomenon has been recognized before in mammals. Behavioral studies indicate a possible role for the glandular secretion in maternal recognition of the young.

Two porcine strains of enteropathogenic Escherichia coli, one possessing K88 antigen and one lacking K88, were orally inoculated into conventional neonatal piglets. Athough both strains caused severe diarrhea, only the K88-possessing strain was able to proliferate in the anterior small intestine. Both K88-possessing and K88-lacking strains were found in large numbers in the posterior small intestine and, using fluorescent antibodies and scanning and transmission electron microscopy, were found adhering to the epitheial surface in these regions. The presence of an unusual surface structure on the bacterial cell of the K88-lacking strain was described.

Lung fluids and leukocytes were obtained from unprimed C3H mice by transpleural lavage at intervals after infection with influenza A/Hong Kong/68 virus and were tested for interferon activity. Lavage fluid interferon titers correlated directly with lung virus titers and with initial increases in leukocyte yields from infected lungs. In contrast to cultured lymph node cells from infected animals or leukocytes from lungs of uninfected mice, washed leukocytes obtained from the lungs of mice infected 2 to 6 days earlier produced interferon spontaneously in culture. The physiochemical, biological, and antigenic properties of both the interferon in lavage fluids and that produced by lung lavage leukocytes were similar and characteristics of alpha interferon. Fractionation studies indicated that macrophages and T lymphocytes were primarily responsible for the interferon produced in culture. The early presence and significant numbers of interferon-producing leukocytes in infected lungs suggests that these cells have an early role in defense against influenza virus infection.

An assay for the detection and quantitation of immune complexes is described. Experimental immune complexes or aggregated human gamma globulin (AHG) were incubated with polymorphonuclear leukocytes (PMN). After challenge of the PMN with opsonized zymosan, chemiluminescence was recorded in a scintillation spectrometer. A quantitative inhibition of chemiluminescence could be demonstrated by the interaction of PMN with immune complexes or AHG. Experimental immune complexes of bovine serum albumin-anti-bovine serum albumin were formed and tested by this assay, and immune complexes formed near antigen excess were best described by this technique. The technique was used to demonstrate immune complexes in the sera from patients with systemic lupus erythematosus, rheumatoid arthritis, and vasculitis. Immune complexes were quantitated by reference to a standard curve using AHG. By this technique, normal human sera had < 10 micrograms of AHG per milliliter of serum. Immune complexes at levels above this were detected in 9/15 patients with systemic lupus erythematosus, 18/30 patients with rheumatoid arthritis, and 2/5 patients with vasculitis. Therefore, this assay is a sensitive, simple method for measurement of circulating immune complexes in the sera of patients with certain connective tissue diseases.

The immunogenic capacity of tobacco smoke or tobacco smoke in combination with host proteins to stimulate antibody production in rabbits was investigated. Several antisera from rabbits immunized with tobacco smoke components reacted by immunoprecipitation with tobacco smoke or leaf antigens. The serum precipitins were present only in immune sera and had electrophoretic mobility and molecular size identical to immunoglobulin. These results suggest that tobacco smoke contains components capable of stimulating an immune response in rabbits. It is possible that these components are immunogenic in man, although their role as allergens remains to be determined.

The life histories of two bivoltine mesophyll-feeding leafhoppers, Lindbergina aurovittata (Douglas) and Edwardsiana rosae (L.), in South Wales are described. L. aurovittata alternates between evergreen Rubus and Quercus in the first generation and various deciduous broad-leaved trees in the second. Experiments on nymphal food preferences and adult oviposition behaviour show that nymphs of both generations tend to prefer older to younger leaves, but show little species specificity. However, adults are discriminating in oviposition preferences, which change regularly and completely in alternating generations. Similar results were obtained with E. rosae. Such obligate seasonal changes in host preferences and utilization are well known amongst aphids, but previously have not been reported in leafhoppers.

The changes with age in serum protein concentrations of 29 normal pigs from 3 litters were estimated. Adult serum protein concentrations were reached by 21–24 weeks of age. Significant litter to litter dif-. ferences in protein concentrations were found in the various age groups. Serum protein concentrations were determined in 327 pigs at 2 days and 3 weeks of age with and without E. coli associated diarrhoea. The gamma globulin concentrations were normally distributed in the 2-day-old pigs and there was no apparent correlation between serum gamma globulin concentrations and incidence of E. coli associated diarrhoea.