Immunocytochemical Identification of the Peripolar Cell and Macula Densa Cell Types

The three "classical" components of the juxtaglomerular apparatus are the myoepithelioid cells, the macula densa cells and the lacis cells, which have been studied for over half a century. This complex multicellular structure is situated in the periglomerular position of every glomerulus, and is responsible for the intrinsic renal control of glomerular filtration rate and tubular reabsorption of sodium, and the regulation of body fluid volume and blood pressure. Complex cellular interactions occur within the juxtaglomerular apparatus. These cells also exhibit physiological relationships with other tissues of the body; but detailed mechanism are still unclear. Ten years ago, a distinctive type of cell, the peripolar cell, was recognised in close anatomical relationship with the juxtaglomerular apparatus. Morphological evidence indicates that the peripolar cell is a secretory type of cell but the substance of the secretory product is unknown. The available data suggests that the peripolar cell might be a previously unrecognised but integral component of the juxtaglomerular apparatus. Its secretory product may be responsible for the hormonal control of renal proximal tubular reabsorption, although this remains speculative

Cytokine Regulation in Systemic Lupus Erythematosus (SLE)

The origin of the defects leading to pathogenicity in systemic lupus erythematosus (SLE), an autoimmune disorder characterised by multi-system involvement, female preference, B-cell hyperactivity, autoantibody production and immune complex deposition, is still controversial. The therapeutic strategies today for treatment of lupus disease are mainly based on a general suppression of the immune system with uncertainty about their long term effects being beneficial or rather harmful to the patients. These treatments that may achieve a temporary symptomatic relief do not cure the disease and are often followed by problematic side effects including infections. The underlying mechanism for the development of the disease is yet to be clarified. There is, however, some evidence that defects in the ability of lymphocytes to produce or respond to cytokines may disturb the finely balanced immune system resulting in abnormal B-cell regulation. In contrast to the B-cell hyperactivity, deficient T-cell functional activity is another prominent feature of the disease. Many cytokine disorders have been reported in both SLE patients and the animal models but findings are often difficult to reconcile, especially differences between data from the in vitro and in vivo studies. In order to understand the mechanism of immune regulation in SLE, experiments were designed, in the present study, to give a detailed analysis of the nature and pathological relevance of those immunological abnormalities, the T-helper cell functional defects in particular. Much of the work focused on and described in this thesis was based mainly on two well established murine models of SLE including an early-life (MRL/lpr) model and a later-life (NZB/W) disease model. Both the NZB/W and the MRL/lpr strains are mutant mice which spontaneously develop a disease similar to human SLE. Female mice of different ages were used in the study and the normal control strains were sex and age-matched BALB/c and CBA mice. Results from studies using lymphocytes and serum samples from SLE patients are also described and compared with the studies on the mouse models. The study included both in vitro and in vivo approaches. Results from the in vitro studies indicate that T-cell, particularly T-helper, functions are severely impaired in the lupus mice. These include abnormal production of IL-2, IFN-gamma and IL-4, inability of T-cells to express functional high affinity IL-2R and to proliferate in response to Con A stimulation, confirming and extending previous studies by other investigators. Since the stage of development at which these defects occur is not clearly understood, efforts have been devoted to analysis of lymphocytes from lupus mice at different ages, in relation to the disease activity. Attention has been particularly focused on young lupus mice including mice of one week old, before the onset of clinical disease. Evidence is given indicating an early onset of the T-helper functional defects and the central role of IL-2 deficiency in the defective T-cell activation. The hyporesponsiveness of lupus T-cells to Con A is due to the inability of T-helper cells to produce IL-2 and this can be bypassed by exogenous IL-2 in vitro. Addition of IL-2 during Con A activation restores fully the ability of lupus T-cells to proliferate, upregulates IL-2R expression and increases the frequency of IFN-gamma secretors resulting in normalised levels of IFN-gamma secretion. T-cell phenotype analysis indicates that IL-2 preferentially promotes the expansion of the functionally more mature single positive cell population while inhibiting the growth of the characteristic CD3+CD4-CD8- (double negative) cells in MRL/lpr mice. Addition of IL-1 during Con A stimulation of T-cells did not restore the IL-2 production defect in the lupus mice. In general, the study indicates a crucial role for the Th1 functional defect and therapeutic potential of IL-2 in SLE. It sheds some doubt on the current clinical treatments by non-specific immunosuppressive drugs and favours approaches which may enhance the endogenous capacity of the immune system to carry out its proper functions in maintaining self-tolerance. The need for new insights into the underlying mechanism of the disease and more consideration of the immune deficient aspects of autoimmune phenomena as a whole for therapeutic strategies are discussed. (Abstract shortened by ProQuest.)

Characterizations of alphaalpha-well-posedness for parametric quasivariational inequalities defined by bifunctions

The purpose of this paper is to investigate the well-posedness issue of parametric quasivariational inequalities defined by bifunctions. We generalize the concept of $alpha$-well-posedness to parametric quasivariational inequalities having a unique solution and derive some characterizations of $alpha$-well-posedness. The corresponding concepts of $alpha$-well-posedness in the generalized sense are also introduced and investigated for the problems having more than one solution. Finally, we give some sufficient conditions for $alpha$-well-posedness of parametric quasivariational inequalities

Silver Metallization of Polyimide Surfaces Using EnvironmentallyFriendly Reducing Agents

Two environmentally friendly reducing agents, ascorbic acid and glucose, were employed to fabricate Ag-thin-film-coated polyimide(PI) films. Ascorbic acid is an acidic reducing agent, whereas glucose is an alkaline reducing agent. Both of these reducing agentsare capable of reducing Ag+ ions doped in poly(amic acid) (PAA) formed by hydrolysis of a PI surface. Only glucose can producea continuous and dense Ag thin film on a PAA surface. Granular and discontinuous Ag thin films were obtained when ascorbic acidwas employed as a reducing agent. This difference in reactivity is attributed to the pH values of these reducing solutions

Clinical study of retinal detachment associated with choroidal detachment

AIM: To analyze the clinical characteristics of retinal detachment associated with choroidal detachment and to evaluate the surgical techniques, the efficacy and operation time for treatment.<p>METHODS: We reviewed and analyzed the operative effects of vitreoretinal surgeries in 45 patients(45 eyes)with retinal and choroidal detachment in our hospital from January, 2010 to January, 2012. In these 45 patients, there were 38 patients of rhegmatogenous retinal detachment associated with choroidal detachment, 7 patients of retinal redetachment associated with choroidal detachment. The surgical techniques include scleral encircling operation, epichoroidal space drainage by sclerocentesis intraocular photocoagulation, gas-fluid exchange, perfluoropropane(C₃F₈)or silicone oil intraocular tamponade and vitreoretinal surgery.<p>RESULTS: The drainage of the suprachoroidal space liquid and blood was successful in 45 eyes. Silicone oil tamponade was performed for 39 eyes and C₃F₈ tamponade for 6 eyes. Retinas and choroids were all reattached and retinal holes were closed. Visual acuities were improved, ≥0.1 in 23 eyes.<p>CONCLUSION: The vitreoretinal surgery and external drainage by sclerocentesis and scleral encircling operation is an effective operating method for rhegmatogenous retinal detachment associated with choroidal detachment

Development of a Generic PCR Detection of 3-Acetyldeoxy-nivalenol-, 15-Acetyldeoxynivalenol- and Nivalenol-Chemotypes of Fusarium graminearum Clade

Fusarium graminearum clade pathogens cause Fusarium head blight (FHB) or scab of wheat and other small cereal grains, producing different kinds of trichothecene mycotoxins that are detrimental to human and domestic animals. Type B trichothecene mycotoxins such as deoxynivalenol, 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON) and nivalenol (NIV) are the principal Fusarium mycotoxins reported in China, as well as in other countries. A genomic polymerase chain reaction (PCR) to predict chemotypes was developed based on the structural gene sequences of Tri13 genes involved in trichothecene mycotoxin biosynthesis pathways. A single pair of primers derived from the Tri13 genes detected a 583 bp fragment from 15-AcDON-chemotypes, a 644 bp fragment from 3-AcDON-chemotypes and an 859 bp fragment from NIV-producing strains. Fusarium strains from China, Nepal, USA and Europe were identified by this method, revealing their mycotoxin chemotypes identical to that obtained by chemical analyses of HPLC or GC/MS and other PCR assays. The mycotoxin chemotype-specific fragments were amplified from a highly variable region located in Tri13 genes with three deletions for 15-AcDON-chemotypes, two deletions for 3-AcDON-chemotypes and no deletion for NIV-producers. This PCR assay generated a single amplicon and thus should be more reliable than other PCR-based assays that showed the absence or presence of a PCR fragment since these assays may generate false-negative results. The results with strains from several different countries as well as from different hosts further indicated that this method should be globally applicable. This is a rapid, reliable and cost-effective method for the identification of type B trichothecene mycotoxin chemotypes in Fusarium species and food safety controls

Dense and accurate motion and strain estimation in high resolution speckle images using an image-adaptive approach

Digital image processing methods represent a viable and well acknowledged alternative to strain gauges and interferometric techniques for determining full-field displacements and strains in materials under stress. This paper presents an image adaptive technique for dense motion and strain estimation using high-resolution speckle images that show the analyzed material in its original and deformed states. The algorithm starts by dividing the speckle image showing the original state into irregular cells taking into consideration both spatial and gradient image information present. Subsequently the Newton-Raphson digital image correlation technique is applied to calculate the corresponding motion for each cell. Adaptive spatial regularization in the form of the Geman-McClure robust spatial estimator is employed to increase the spatial consistency of the motion components of a cell with respect to the components of neighbouring cells. To obtain the final strain information, local least-squares fitting using a linear displacement model is performed on the horizontal and vertical displacement fields. To evaluate the presented image partitioning and strain estimation techniques two numerical and two real experiments are employed. The numerical experiments simulate the deformation of a specimen with constant strain across the surface as well as small rigid-body rotations present while real experiments consist specimens that undergo uniaxial stress. The results indicate very good accuracy of the recovered strains as well as better rotation insensitivity compared to classical techniques

Regulatory B Cells - Implications in Autoimmune and Allergic Disorders

B lymphocytes are a major player in the immune system and their best understood effector functions are antibody production, presentation of antigens to T cells and modulation of immune responses via cytokine production. Most B cell functions are considered to amplify immune responses, but it has also been demonstrated that due to production of immunosuppressive cytokines or antibodies, B cells can down-regulate immune responses and have the ability to induce tolerance. These B cells with regulatory capacity (Breg cells) have been shown to suppress effector functions of various target cells including T cells, dendritic cells and macrophages, and can even convert effector T cells into regulatory T cells. The most prominent mechanism of Breg mediated suppression is the release of anti-inflammatory cytokines such as IL-10 and TGF-β. Additional suppression mechanisms via cell-cell contact, involving surface molecules such as program death-1 (PD-1), CD80/CD86 and FasL mediating target cell apoptosis, have been described as well. Most importantly, Breg cells have been implicated in various inflammatory conditions, such as allergic and autoimmune diseases. There is evidence for Breg deficiencies in human SLE patients and various adoptive transfer experiments in mouse models of autoimmune and allergic diseases indicate that Breg cells are capable of suppressing disease development. In this review we endeavour to give an overview of the current knowledge about regulatory B cell immunobiology and their implications in allergic and autoimmune conditions.published_or_final_versio