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Background Fcε RIβ reportedly functions as an amplifier of the Fcε RIγ-mediated activation signal using a reconstitution system. However, the amplification mechanisms in human mast cells ( MCs) are poorly understood. We previously reported the hyperexpression of Fcε RIβ of MCs in giant papillae from vernal keratoconjunctivitis patients, compared with that in conjunctivae from nonallergic conjunctivitis patients. Elucidation of the molecular mechanisms of the amplification induced by Fcε RIβ should provide new targets for novel therapeutic interventions. The aim is to understand in greater details the function of Fcε RIβ in human MC Fcε RI expression and signaling. Methods Fcε RIβ and Lyn expression was reduced using a lentiviral sh RNA silencing technique. Localization of Lyn and Fcε RIβ in cultured MCs was examined by confocal microscopic analysis. Mediators were measured by ELISAs. Results The diminution of Fcε RIβ significantly downregulated cell surface Fcε RI expression and Fcε RI-mediated mediator release/production. The downregulation of Fcε RI-mediated degranulation was not only due to the decrease in Fcε RI expression. The diminution of Fcε RIβ inhibited the redistribution of Lyn within the cell membrane following Ig E sensitization. The diminution of Lyn in MCs significantly downregulated Fcε RI-mediated degranulation. The recombinant cell-penetrating forms of phosphorylated Fcε RIβ immunoreceptor tyrosine-based activation motif ( ITAM) for intracellular delivery disturbed the interaction between Lyn and phosphorylated endogenous Fcε RIβ ITAM, resulted in inhibiting Ig E-dependent histamine release from MCs in vitro and from giant papillae specimens ex vivo. Conclusion The interaction between Lyn and Fcε RIβ is indispensable for Fcε RI-mediated human MC activation, and specific inhibition of the interaction may represent a new therapeutic strategy for the treatment of human allergic diseases. [ABSTRACT FROM AUTHOR]

Because impaired insulin secretion is characteristic of type 2 diabetes in Asians, including Japanese, the genes involved in pancreatic beta-cell function are candidate susceptibility genes for type 2 diabetes. We examined the association of variants in genes encoding several transcription factors (TCF1, TCF2, HNF4A, ISL1, IPF1, NEUROG3, PAX6, NKX2-2, NKX6-1, and NEUROD1) and genes encoding the ATP-sensitive K(+) channel subunits Kir6.2 (KCNJ11) and SUR1 (ABCC8) with type 2 diabetes in a Japanese cohort of 2,834 subjects. The exon 16 -3c/t variant rs1799854 in ABCC8 showed a significant association (P = 0.0073), and variants in several genes showed nominally significant associations (P < 0.05) with type 2 diabetes. Although the E23K variant rs5219 in KCNJ11 showed no association with diabetes in Japanese (for the K allele, odds ratio [OR] 1.08 [95% CI 0.97-1.21], P = 0.15), 95% CI around the OR overlaps in meta-analysis of European populations, suggesting that our results are not inconsistent with the previous studies. This is the largest association study so far conducted on these genes in Japanese and provides valuable information for comparison with other ethnic groups. [ABSTRACT FROM AUTHOR]

The allele frequencies for a Pro12-->Ala substitution in peroxisome proliferator-activated receptor-gamma differ among ethnic groups, and its relationship with diabetes and associated diseases is controversial. The prevalence of this polymorphism and its effects on clinical characteristics have now been evaluated with a large number of Japanese individuals with type 2 diabetes (n = 2,201) and normal control subjects (n = 1,212) recruited by 10 institutions located in seven different cities in Japan. The allele frequency for the Ala12 variant was significantly lower in the type 2 diabetic group than in the control group (2.39 vs. 4.13%, P = 0.000054). However, compared with subjects without the Ala12 variant, the diabetic subjects with this variant exhibited a significantly higher serum concentration of total cholesterol (P = 0.001), manifested a reduced capacity for insulin secretion as evaluated by homeostasis model assessment (P = 0.007), and tended to possess a higher level of HbA1c. These data suggest that the Ala12 variant is associated with a reduced risk for the development of diabetes in the general population, but that it may be also a risk factor for insulin deficiency and disease severity in individuals with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The article discusses assignment of the human solute carrier family 4, sodium bicarbonate cotransporter like, member 10 gene (SLC4A10) to 2q23->q24 by insitu hybridization and radiation hybrid mapping. Recently, a novel cDNA encoding a bicarbonate transporter-like protein was isolated from the mouse insulin secreting cell line MIN6 cDNA library. A part of the human homolo- gue of the gene, SLC4A 10 has been cloned and mapped to human chromosome 2q23->q24. To confirm the chromo- somal location, somatic cell hybrid mapping and radiation hybrid mapping were performed.

Aims The essential role of basophils as an initiator of chronic allergic reaction has been elucidated in mouse models. The aim of this present study was to analyse the in situ immunolocalisation of basophils and other relevant inflammatory cells in chronic allergic keratoconjunctivitis. Methods Transmission electron microscopic (TEM) analysis was carried out to examine the existence of basophils in the giant papillae obtained from atopic keratoconjunctivitis (AKC) and vernal keratoconjunctivitis (VKC) patients. Cryostat sections of giant papillae were immunostained with basophil-specific antibody BB-1, and with anti-CD4, anti-CD8, anti-CD20, anti-major basic protein (MBP), anti-IgE and anti-FcϵRI-β antibodies. Results TEM analysis confirmed the existence of basophils in the giant papillae. Small clusters of basophils were observed in the substantia propria of giant papillae, especially at the vicinity of vascular endothelium and subepithelial regions. BB-1-positive basophil clusters were surrounded by T cells, B cells, IgE-positive cells and MBP-positive eosinophils. No BB-1-positive basophils were observed in the control conjunctivae. Conclusion Basophils may infiltrate from either vascular endothelium into the giant papillae. The existence of basophils at the centre of inflammatory cells suggests the role of basophils as an initiator of chronic allergic conjunctivitis. [ABSTRACT FROM AUTHOR]

Abstract: Tear hyperosmolarity is thought to play a key role in the mechanism of dry eye, a common symptomatic condition accompanied by visual disturbance, tear film instability, inflammation and damage to the ocular surface. We have constructed a model for the mass and solute balance of the tears, with parameter estimation based on extensive data from the literature which permits the influence of tear evaporation, lacrimal flux and blink rate on tear osmolarity to be explored. In particular the nature of compensatory events has been estimated in aqueous-deficient (ADDE) and evaporative (EDE) dry eye. The model reproduces observed osmolarities of the tear meniscus for the healthy eye and predicts a higher concentration in the tear film than meniscus in normal and dry eye states. The differential is small in the normal eye, but is significantly increased in dry eye, especially for the simultaneous presence of high meniscus concentration and low meniscus radius. This may influence the interpretation of osmolarity values obtained from meniscus samples since they need not fully reflect potential damage to the ocular surface caused by tear film hyperosmolarity. Interrogation of the model suggests that increases in blink rate may play a limited role in compensating for a rise in tear osmolarity in ADDE but that an increase in lacrimal flux, together with an increase in blink rate, may delay the development of hyperosmolarity in EDE. Nonetheless, it is predicted that tear osmolarity may rise to much higher levels in EDE than ADDE before the onset of tear film breakup, in the absence of events at the ocular surface which would independently compromise tear film stability. Differences in the predicted responses of the pre-ocular tears in ADDE compared to EDE or hybrid disease to defined conditions suggest that no single, empirically-accessible variable can act as a surrogate for tear film concentration and the potential for ocular surface damage. This emphasises the need to measure and integrate multiple diagnostic indicators to determine outcomes and prognosis. Modelling predictions in addition show that further studies concerning the possibility of a high lacrimal flux phenotype in EDE are likely to be profitable. [Copyright &y& Elsevier]

Abstract: Background: Our genomewide association study documented an association between cold medicine‐related Stevens‐Johnson syndrome/toxic epidermal necrolysis (CM‐SJS/TEN) and Ikaros Family Zinc Finger 1 (IKZF1). Few studies examined biological and pathological functions of IKZF1 in mucosal immunity. We hypothesized that IKZF1 contributes to the mucocutaneous inflammation. Methods: Human skin and conjunctival tissues were obtained for immunohistological studies. Primary human conjunctival epithelial cells (PHCjECs) and adult human epidermal keratinocytes (HEKa) also used for gene expression analysis. We also generated K5‐Ikzf1‐EGFP transgenic mice (Ikzf1 Tg) by introducing the Ik1 isoform into cells expressing keratin 5, which is expressed in epithelial tissues such as the epidermis and conjunctiva, and then examined them histologically and investigated gene expression of the epidermis. Moreover, Ikzf1 Tg were induced allergic contact dermatitis. Results: We found that human epidermis and conjunctival epithelium expressed IKZF1, and in PHCjECs and HEKa, the expression of IKZF1 mRNA was upregulated by stimulation with polyI:C, a TLR3 ligand. In Ikzf1 Tg, we observed dermatitis and mucosal inflammation including the ocular surface. In contact dermatitis model, inflammatory infiltrates in the skin of Ikzf1 Tg were significantly increased compared with wild type. Microarray analysis showed that Lcn2, Adh7, Epgn, Ifi202b, Cdo1, Gpr37, Duoxa1, Tnfrsf4, and Enpp5 genes were significantly upregulated in the epidermis of Ikzf1 Tg compared with wild type. Conclusion: Our findings support the hypothesis that Ikaros might participate in mucocutaneous inflammation. [ABSTRACT FROM AUTHOR]

Abstract: The flow characteristics of circulating water in a proton exchange membrane (PEM) electrolyzer were experimentally evaluated using a small cell and two-phase flow theory. Results revealed that when a two-phase flow of circulating water at the anode is either slug or annular, then mass transport of the water for the anode reaction is degraded, and that the concentration overvoltage increases at higher current density compared to that when the flow is bubbly. In a serpentine-dual flow field, when both phases of the two-phase flow are assumed laminar, then the increase in pressure drop caused by the increase in gas production can be explained relatively well using the Lockhart–Martinelli method with the Chisholm parameter. The optimal flow rate of circulating water was also discussed based on mass balance analysis. [ABSTRACT FROM AUTHOR]

Purpose: The expression and function of Toll-like receptor 5 (TLR5) was analysed in human conjunctival epithelial cells (HCjEC). Methods: The expression of TLR5 in HCjEC was studied by reverse transcriptase (AT) PCR and flow cytometry. The amount of interleukin (IL) 6 and IL-8 proteins was determined by ELISA. Messenger RNA expression elicited by stimulation with flagellins derived from Pseudomonas aeruginosa, Serratia marcescens, Salmonella typhimurium and Bacillus subtilis was assayed by quantitative RT-PCR. The localisation of TLR5 protein in human conjunctival epithelium was detected immunohistochemically. Results: HCjEC expressed TLR5-specific mRNA and TLA5 protein. In HCjEC stimulated with flagellins derived from P aeruginosa and S marcescens, IL-6 and IL-8 production was increased and IL-6 and lL-8 mANA was upregulated. Flagellins from S typhimurium and B subtilis did not induce the upregulation of these genes and proteins. TLR5 protein was detected on the basolateral but not the apical side of human conjunctival epithelium. Conclusions: Human conjunctival epithelium harbours functional TLR5. Considering the spatially selective basolateral localisation of TLR5 protein, it was postulated that flagellins from ocular pathogenic bacteria induce inflammatory responses when disruption of the epithelial barrier permits their transmigration to the basolateral side but not under healthy physiological conditions on the ocular surface. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the risk factors for rubeosis iridis by colour Doppler imaging (CDI) in patients with complete internal carotid artery occlusion (ICAO). Methods: 34 eyes of 32 consecutive patients with complete ICAO were enrolled. Using CDI, blood flow direction (forward, reverse, undetectable) in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliory artery (SPCA) were determined. Arterial mean blood velocity (Vmean) and resistive index (RI) were calculated and correlations between the rubeosis iridis incidence and CDI parameters analysed. Results: The eyes were classified into four types according to blood flow direction: forward flow in OA, CRA, and SPCA (type 1; n = 11); reverse OA and forward CRA and SPCA How (type 2a; n = 12); reverse OA and undetectable CRA and SPCA How (type 2b; n = 8); undetectable How in all three arteries (type 3; n=3). Rubeosis iridis was seen only in type 2b and 3 eyes. Type 2b showed significantly (p<0.01) higher Vmean and lower RI values in the OA, indicating more rapid reverse How than in type 2a eyes. Although in type 1 and 2a eyes OA flow was in opposite directions, they manifested no rubeosis iridis and no difference in the Ymean and RI values of the CRA and SPCA. Conclusions: The classification of eyes from patients with ICAO into four types by CDI may facilitate the identification of the eyes at high risk for rubeosis iridis. Markedly diminished How in both the CRA and SPCA may result in rubeosis iridis, regardless of OA How direction. [ABSTRACT FROM AUTHOR]

The lipid layer is an essential component of the tear film, providing a smooth optical surface for the cornea and retarding evaporation from the eye. The meibomian lipids which compose it are well adapted for this purpose. They form a thin, smooth film whose thickness, and probably composition, influences the rate of evaporation. Their melting range ensures sufficient fluidity for delivery to the tear film from the lid margin reservoirs, while the film itself may exhibit a higher viscosity at the cooler temperature of the ocular surface. The factors governing lipid film formation during the blink are not fully understood, but one view is that the polar lipids, interacting with the aqueous sub-phase of the tear film, spread in advance of the non-polar components, which form the bulk of the film. The meibomian lipids stabilise the tear film by lowering its free energy; they carry water into the film during its formation and interact with lipid-binding proteins in the aqueous phase, such as tear lipocalin. The lipocalins, complexed with other tear components, may also contribute to the high, non-Newtonian viscosity of the tear film and its low surface tension, features which are essential for tear film stability.Formation of the lipid film is a complex process. Lipid is delivered to the tear film in the up-phase of the blink, more from the lower than the upper reservoir. The lipid layer comes to a stop well after completion of the blink and remains relatively immobile until it is compressed in the down-phase of the blink that follows. Then, it either retains its structure in a series of subsequent blinks, or is completely re-constituted after mixing with the reservoir lipids.Delivery of meibomian lipid to the marginal reservoirs is mainly the result of continuous secretion, under neural and hormonal control, supplemented by lid action. The reservoirs provide a hydrophobic barrier to tear overspill and to contamination by skin lipids which might destabilise the tear film. They probably also provide the chief route for meibomian lipid excretion. [Copyright &y& Elsevier]