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Braff Marissa H - - 2005
Immune defense at an interface with the external environment reflects the functions of physical and chemical barriers provided by epithelial and immune cells. Resident epithelial cells, such as keratinocytes, produce numerous peptides with direct antimicrobial activity but also provide a physical barrier against invading pathogens and signal the recruitment of ...
Buist Harrie E - - 2005
The dermal route of exposure is important in worker exposure to biocidal products. Many biocidal active substances which are used on a daily basis may decrease the barrier function of the skin to a larger extent than current risk assessment practice addresses, due to possible skin effects of repeated exposure. ...
Takasawa R - - 2005
The induction of apoptosis in keratinocytes by ultraviolet (UV)-irradiation is considered to be a protective function against skin cancer. UV-induced DNA damage is a crucial event in UVB- and UVC-mediated apoptosis. However, the differences between the UVB- and UVC-induced apoptotic pathways remain unclear. Here we examine the differential mechanisms by ...
Raap Ulrike - - 2005
PURPOSE OF REVIEW: Recent studies have gained widespread information about the complex regulation of genetic, environmental, immunologic, and pharmacologic factors that contribute to the development of allergic inflammatory skin diseases such as atopic dermatitis. Neuroimmune mechanisms, however, still remain to be elucidated. This review will focus on the interaction between ...
Bynoe Margaret S - - 2005
The rebirth of interest in suppressor T cells has spawned a vast amount of data that shed light on their biology and role in immune system homeostasis. Since the early studies on the naturally occurring CD4+/CD25+ T regulatory cells, much attention has been focused on ways to induce suppressor T ...
Niyonsaba Fran?ois - - 2005
Beside its physical barrier against invading microorganisms, the skin has the ability to produce a number of antimicrobial peptides and proteins, including human beta-defensins, cathelicidin LL-37 and lysozyme that participate in the innate host defense. These antimicrobial agents are strongly active against a wide spectrum of various pathogens such as ...
De Vry Christopher G - - 2005
RDP58 is the first lead compound in a series of immunomodulating decapeptides discovered through activity-based screening and computer-aided, rational design. RDP58 disrupts cellular responses signaled through the Toll-like and tumor necrosis factor (TNF) receptor families and occludes important signal transduction pathways involved in inflammation, inhibiting the production of tumor necrosis ...
Fourtanier Anny - - 2005
It is increasingly accepted that sunscreens should protect against ultraviolet radiation (UVR)-induced immunosuppression, with an index of protection that can be compared with the sun protection factor (SPF). Five groups of immunoprotection researchers met to discuss the status of immune protection factor (IPF) evaluation in human skin in vivo. Current ...
Galadari Ibrahim - - 2005
Psoriasis is a disease characterized by scaly skin lesions secondary to keratinocyte hyperplasia. The presence of active T cells in the lesions, experimental observations on disease transfer, and therapeutic efficacy of specific immunosuppressive drugs have led to the identification of the activated T lymphocyte as the primary factor for keratinocyte ...
Bowcock Anne M - - 2005
Psoriasis is a chronic inflammatory disorder of the skin that is mediated by T cells, dendritic cells and inflammatory cytokines. We now understand many of the cellular alterations that underlie this disease, and genomic approaches have recently been used to assess the alterations of gene expression in psoriatic skin lesions. ...
El-Abaseri Taghrid B - - 2006
Chronic exposure to ultraviolet (UV) irradiation induces skin cancer, in part, through epigenetic mechanisms that result in the deregulation of cell proliferation. UV irradiation also rapidly activates the epidermal growth factor receptor (EGFR). Since EGFR activation is strongly mitogenic in many cell types including keratinocytes of the skin, we hypothesized ...
Li-Weber Min - - 2005
UV irradiation is carcinogenic and immunosuppressive. Previous studies indicate that UV-mediated alteration of APCs and induction of suppressor T cells play a critical role in UV-induced immune suppression. In this study, we show that UV irradiation can directly (independently of APCs and suppressor T cells) inhibit T cell activation by ...
Pi Jingbo - - 2005
Inorganic arsenic is a human carcinogen that targets the skin. Carcinogenesis is a multistep process in which acquired apoptotic resistance is a common event and prior work in non-skin cells shows acquired resistance to apoptosis occurs with chronic arsenite exposure. In the present study, when HaCaT cells, an immortalized, non-tumorigenic ...
Böhm Markus - - 2005
Proopiomelanocortin (POMC)-derived peptides and their receptors have been identified in many peripheral organs including the skin in which they exert a diversity of biological actions. We investigated the expression and potential role of the POMC system in human dermal papilla cells (DPCs), a specialized cutaneous mesenchymal cell type regulating hair ...
Raveh Eli - - 2005
Transcriptional regulators of the Runx family play critical roles in normal organ development and, when mutated, lead to genetic diseases and cancer. Runx3 functions during cell lineage decisions in thymopoiesis and neurogenesis and mediates transforming growth factor-beta signaling in dendritic cells. Here, we study the function of Runx3 in the ...
Myers Wendy - - 2005
Alefacept is a dimeric fusion protein that consists of the extracellular CD2-binding portion of human lymphocyte function-associated antigen-3, which is linked to the Fc segment of human IgG1. Alefacept inhibits T-cell activation and proliferation, and induces apoptosis of memory-effector (CD45RO+) T cells in vitro, limiting the inflammatory and uncontrolled keratinocyte ...
Assefa Zerihun - - 2005
Epidemiological and experimental evidences have established solar ultraviolet (UV) radiation as the leading cause of skin cancers. Specifically, the frequency of non-melanoma skin cancer, one of the malignancies with the most rapidly increasing incidence, is directly related to the total exposure to solar UV light. As part of a general ...
Kuchel Johanna M - - 2005
We tested the hypothesis that DNA is a target for solar-simulated ultraviolet radiation (ssUVR)-induced suppression of the reactivation of memory immunity in humans. T4N5 liposomes contain the DNA repair enzyme T4 endonuclease V. This cleaves DNA at the site of ultraviolet radiation (UVR)-induced cyclobutane pyrimidine dimers (CPD), initiating DNA repair. ...
Cywes Bentley Colette - - 2005
Group A Streptococcus (GAS) colonizes the oropharynx and damaged skin. To cause local infection or severe invasive syndromes the bacteria must gain access into deeper tissues. Host cell death may facilitate this process. GAS internalization has been identified to induce apoptosis. We now report an alternate mechanism of GAS-mediated apoptosis ...
Pivarcsi Andor - - 2005
Atopic dermatitis is a chronic or chronically relapsing inflammatory skin disease with a prevalence ranging from 10% to 20% in children and 1% to 3% in adults of developed countries. Skin-infiltrating leukocytes play a pivotal role in the initiation and amplification of atopic skin inflammation. Recent studies demonstrated that infiltration ...
Schaller M - - 2005
BACKGROUND: The inflammation in acne vulgaris is widely thought to be induced by an immunological reaction, but the role of Propionibacterium acnes is unclear. OBJECTIVES: To examine the local host response mechanism of a keratinocyte cell line 3 h and 6 h after stimulation with viable and heat-killed P. acnes. ...
Zheng Tao - - 2005
Atopic dermatitis (AD) is a complex disease that manifests immunologic abnormalities in the skin. The immunologic changes of AD are characterized by a T helper cell type 2 (Th2)-dominated immune response in its acute phase and a Th1/Th2 mixed immune response in its chronic phase. Although the clinical presentation and ...
Ezendam Janine - - 2005
Hexachlorobenzene (HCB) is an environmental pollutant that induces adverse immune effects in humans and rats. Brown Norway rats (BN) appear to be very susceptible to HCB-induced immune effects. Oral exposure causes inflammatory skin and lung lesions, enlarged spleen and lymph nodes (LN) and elevated humoral responses. This review describes recent ...
Shepherd Andrew J - - 2005
Capsaicin-mediated depletion of neuropeptides in the skin was previously shown to abolish a dinitrocholorobenzene (DNCB)-induced contact sensitivity (CS) response. To understand the basis for this disruption, we explored whether nerve fibres innervating the draining lymph node (LN) could be involved. As expected, removal of the draining LN after DNCB sensitisation ...
Engelhart Karin - - 2005
Dermatitis is a group of highly pruritic chronic inflammatory skin diseases which represents a major public-health problem worldwide. The prevalence of dermatitis has increased in recent years affecting up to 20% of the general population. Acute skin lesions are characterized by extensive degrees of intercellular edema of the epidermis (spongiosis) ...
Schwarz Thomas - - 2005
Regulatory T cells belong to a subset of T lymphocytes which suppress immune reactions in an antigen-specific fashion. They play an important role in the prevention of autoimmune diseases. Ultraviolet (UV) radiation was also found to suppress the immune system in an antigen-specific fashion mediated by UV-induced regulatory T cells. ...
Liu Luzheng - - 2005
Iatrogenic cutaneous infection with vaccinia virus (VV) and naturally occurring systemic infection with variola virus both lead to the characteristic skin "pox" lesions. Despite significant medical experience with both viruses, surprisingly little is understood about the interactions between these poxviruses and healthy resident skin cells. In recent years, it has ...
Pernet I - - 2005
Normal human skin controls the intrusion of microorganisms by the production of peptide antibiotics such as defensins. The aim of our study was to develop a culture model of normal human keratinocytes for optimal beta-defensin mRNA detection which allows the screening of molecules able to stimulate hBD2 and hBD3 without ...
Boyman O - - 2005
Psoriasis is a common and chronic relapsing inflammatory skin disorder. Although a role for T cells in mediating the induction and maintenance of psoriatic lesions is well established, mechanisms responsible for activation of T cells by antigen-presenting cells (APCs) during disease relapse are poorly understood. (i) To determine whether expression ...
Andersson Anna K - - 2005
Leprosy type 1 reactions (T1R) are due to increased cell-mediated immunity and result in localized tissue damage. The anti-inflammatory drug prednisolone is used for treatment, but there is little good in vivo data on the molecular actions of prednisolone. We investigated the effect of prednisolone treatment on tumor necrosis factor ...
Mägert Hans-Jürgen - - 2005
Serine proteinases fulfill and facilitate a broad spectrum of biological processes. They are held in check by different specific inhibitors. This delicate balance can be disturbed by genetic defects or exogenous influences and has been shown as the underlying or promoting cause for a large number of different diseases. For ...
Albanesi Cristina - - 2005
Although in the past, keratinocytes were considered simply as passive targets of immunological attack from infiltrating T lymphocytes, a number of studies have definitively demonstrated that keratinocytes actively participate in the cutaneous immune responses. Upon activation, keratinocytes express a plethora of cytokines, chemokines and accessory molecules, which can transmit both ...
Sigmundsdottir Hekla - - 2005
Narrow-band ultraviolet B (UVB) phototherapy is an effective treatment for psoriasis. Owing to its limited penetration, the direct effects of UVB are mostly restricted to cells residing in the epidermis and papillary dermis, and are associated with epidermal depletion of Langerhans' cells (LC) and T cells. It has been argued ...
Peters Eva Milena J - - 2005
Stress is said to induce itchiness of the skin, exacerbate inflammatory skin diseases, and inhibit wound healing. Neuropeptides such as substance P (SP) may play a role in these processes. Recently, we were able to show that both stress or SP are associated with neurogenic inflammation and increased apoptosis in ...
Markkula S Eveliina - - 2005
Carp (Cyprinus carpio) were repeatedly exposed to 0, 60, 120 and 240 mJ/cm2 ultraviolet B (UVB) radiation three times in 1 week (short-term exposure) or 12 times in 4 weeks (long-term exposure). The effect of UVB on the functioning of the carp immune system was studied on day 2 after ...
Pastore Saveria - - 2005
Resident cell populations of the skin contribute to the inflammatory response by producing an array of chemokines, which attract leukocytes from the circulation. TNF-alpha is a major inducer of proinflammatory mediators in keratinocytes. We have recently observed that epidermal growth factor receptor (EGFR) signaling affects TNF-alpha-driven chemokine expression in epidermal ...
Hirota Ayako - - 2005
Ultraviolet (UV) radiation is one of the most important environmental factors involved in the pathogenesis of skin aging and cancer. Many harmful effects of UV radiation are associated with the generation of reactive oxygen species, and cellular antioxidants act to prevent the occurrence and reduce the severity of UV-induced skin ...
Metcalfe A D - - 2005
Biomedical science has made major advances in understanding how cells grow into functioning tissue and the signalling mechanisms used to achieve this are slowly being dissected. Tissue engineering is the application of that knowledge to the building or repairing of organs, including skin, the largest organ in the body. Generally, ...
Schön Michael P - - 2005
Tissue-selective recruitment of lymphocytes to peripheral organs, such as the skin, is crucial for spatial compartmentalisation within the immune system as well as immune surveillance under normal conditions. In addition, this process plays a key role for the pathogenesis of various diseases including common inflammatory disorders such as atopic dermatitis ...
Braff Marissa H - - 2005
Cathelicidins and other antimicrobial peptides are deployed at epithelial surfaces to defend against infection. These molecules have broad-spectrum killing activity against microbes and can have effects on specific mammalian cell types, potentially stimulating additional immune defense through direct chemotactic activity or induction of cytokine release. In humans, the cathelicidin hCAP18/LL-37 ...
Kuwahara Keiichi - - 2005
BACKGROUND: Acne vulgaris is a chronic inflammatory disease involving colonization of Propionibacterium acnes (P. acnes), activation of neutrophils and lymphocytes. Circumstantial evidence suggests that antigen-independent and -dependent immune responses against P. acnes are involved in the pathogenesis of inflammatory acne. Epidermal keratinocytes are also suggested to be involved in initiation ...
Schade Nicole - - 2005
About 30 years ago, the discovery of the connection between UV radiation and the immune system triggered the field of photoimmunology. In that time, many aspects were studied, and a complex picture emerged. UV absorption results in multi-tiered molecular and cellular UV radiation-induced events, eventually affecting the immune system. The ...
Namazi Mohammad R - - 2005
Psoriasis is a clinical conundrum that affects an estimated 1-3% of the world's population. The psoriatic disease process, characterized by a type 1 cytokine pattern, is supposed to be maintained by a continuing immune response in a "peripheral lymphoid tissue" that forms in lesional skin and is composed of T ...
Sakkas Lazaros I - - 2005
Systemic sclerosis (SSc) is characterized by extensive fibrosis, vasculopathy and activation of the immune system. Fibrosis can be caused by profibrotic cytokines, such as transforming growth factor-beta (TGFbeta), interleukin-4 (IL-4), platelet-derived growth factor (PDGF), and connective tissue growth factor. Vasculopathy can be caused by TGFbeta, PDGF, while paucity of vessels ...
Allanson Munif - - 2005
Accumulating evidence suggests that suberythemogenic ultraviolet A (UVA) (320-400 nm) exposure protects against the immunosuppressive effect of ultraviolet B (290-320 nm) radiation or its epidermal photoproduct, cis-urocanic acid (cis-UCA). In skin, UVA photoimmunoprotection is mediated by the inducible antioxidant stress enzyme, heme oxygenase-1 (HO-1), which degrades heme into carbon monoxide ...
Novak N - - 2005
For a long time, therapeutic strategies of atopic dermatitis (AD) have been dominated by the application of local or systemic steroids or other immunosuppressive agents, which have been limited by their potential for unwanted local or systemic side effects. Recently, the use of a new generation of topical nonsteroidal, immunomodulatory ...
Wenzel Joerg - - 2005
Recent studies have suggested that type I interferons (IFN) play a role in the pathogenesis of lupus erythematosus (LE), an autoimmune disease of unknown aetiology. Natural interferon-producing plasmacytoid cells have been demonstrated in cutaneous LE (CLE) lesions, along with elevated levels of IFN-alpha mRNA. The hypothesis in the current study ...
Birch K E - - 2005
Regulatory T cells are thought to have a critical role in the suppression of immune responses. In addition to the prevention of the development of autoimmunity, they are also thought to have a role in the prevention of allergic responses to environmental allergens, immune responses to tumours and the development ...
Nagafuchi H - - 2005
Excessive Th1 cell function is importantly involved in the pathogenesis of Behcet's disease (BD). We previously found that Txk, a member of the Tec family of tyrosine kinases, acts as a Th1 cell specific transcription factor. To investigate immune aberration in the pathogenesis of BD, we studied the expression of ...
Lenz Holger - - 2005
Cutaneous aging is characterized by a decline in cellular energy metabolism, which is mainly caused by detrimental changes in mitochondrial function. The processes involved seem to be predominantly mediated by free radicals known to be generated by exogenous noxes, e.g., solar ultraviolet (UV) radiation. Basically, skin cells try to compensate ...
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