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ID PMID Title PublicationDate abstract
20436081 Androgens and integrins in salivary glands in Sjogren's syndrome. 2010 Jun OBJECTIVE: Laminin alpha1-chain normally induces intercalated duct progenitors to differentiate to acinar cells through integrin (INT) alpha1ss1 and alpha2ss1 receptors. Maintenance of acinar cells is impaired in Sjögren's syndrome (SS), which is also characterized by low levels of serum and salivary androgens. We hypothesized that androgens normally support salivary gland remodeling by upregulating either laminin alpha1 chain or its cellular alpha1 or alpha2 INT subunit-containing receptors. METHODS: Intercalated duct and acinar human salivary gland (HSG) cells and labial salivary gland (LSG) biopsies from healthy controls and patients with SS were cultured without or with sex steroids. Laminin alpha1 chain and INT alpha1 and alpha2 subunits were studied using quantitative reverse-transcription real-time polymerase chain reaction and INT alpha1 and alpha2 subunits using immunofluorescence staining. RESULTS: INT alpha1-subunit and alpha2-subunit messenger RNA (mRNA) levels were increased in intercalated duct and acinar cells by DHEA and testosterone. In contrast, laminin alpha1-chain mRNA levels were not affected. The upregulating effect of DHEA on INT subunits was also seen at the protein level. DHEA also increased mRNA levels of both INT subunits in healthy but not SS LSG. CONCLUSION: Androgens increased INT alpha1 and alpha2 subunits in tubuloepithelial cells and in healthy LSG, but in SS salivary glands this androgen regulation was defective, which is likely to contribute to defective outside-in signaling, acinar atrophy, and ductal cell hyperplasia.
19841086 A hypomorphic allele of ZAP-70 reveals a distinct thymic threshold for autoimmune disease 2009 Oct 26 ZAP-70 is critical for T cell receptor (TCR) signaling. Tyrosine to phenylalanine mutations of Y315 and Y319 in ZAP-70 suggest these residues function to recruit downstream effector molecules, but mutagenesis and crystallization studies reveal that these residues also play an important role in autoinhibition ZAP-70. To address the importance of the scaffolding function, we generated a zap70 mutant mouse (YYAA mouse) with Y315 and Y319 both mutated to alanines. These YYAA mice reveal that the scaffolding function is important for normal development and function. Moreover, the YYAA mice have many similarities to a previously identified ZAP-70 mutant mouse, SKG, which harbors a distinct hypomorphic mutation. Both YYAA and SKG mice have impaired T cell development and hyporesponsiveness to TCR stimulation, markedly reduced numbers of thymic T regulatory cells and defective positive and negative selection. YYAA mice, like SKG mice, develop rheumatoid factor antibodies, but fail to develop autoimmune arthritis. Signaling differences that result from ZAP-70 mutations appear to skew the TCR repertoire in ways that differentially influence propensity to autoimmunity versus autoimmune disease susceptibility. By uncoupling the relative contribution from T regulatory cells and TCR repertoire during thymic selection, our data help to identify events that may be important, but alone are insufficient, for the development of autoimmune disease.
20605287 [Kikuchi-Fujimoto disease]. 2010 Nov Kikuchi-Fujimoto disease is a necrotizing lymphadenitis, involving young patients, predominantly females. Lymphadenopathy is usually localized, particularly in the cervical area, mostly unilateral and tender. Fever is present in one third of cases. Associated skin lesions, arthralgia, myalgia, splenomegaly or hepatomegaly are rare. Laboratory evaluation shows a slight increase of erythrocyte sedimentation rate and leukopenia. Kikuchi-Fujimoto has been reported in association with other diseases, including systemic lupus, Still's disease, hemophagocytosis, pregnancy, other autoimmune diseases, and cancer. A viral or bacterial origin has been suspected but not confirmed. Lymph node biopsy allows the diagnosis and shows necrotizing lymphadenitis with acidophil necrosis, CD68+ histiocyte infiltrate, presence of plasmacytoid monocytes, multiple apoptotic cells (CD8+ T cell) with nuclear dust, immunoblastic reaction and the absence of neutrophils or eosinophils. The disease course is usually spontaneously favourable in few weeks or months, requiring corticosteroids only occasionally.
19298243 Nuclear BCL10 in primary Sjögren's syndrome. 2009 Jul BACKGROUND: The events following triggering of antigen receptors and subsequent activation of the transcription factor nuclear factor kappa B (NFkappaB) need to be carefully controlled to prevent abnormal immune responses. BCL10 links the antigen receptor to NFkappaB. The aim of this study was to determine the expression pattern of BCL10 and NFkappaB in minor salivary gland infiltrates of patients with primary Sjögren's syndrome (pSS). METHODS: Minor salivary glands from patients with primary SS (n = 17) and sicca controls (n = 4) were evaluated by single and double immunohistochemistry and immunofluorescence for confocal microscopy. BCL10 and NFkappaB-p65 expression were evaluated in the infiltrating lymphocytes. Ectopic germinal centers (GCs) were investigated by CD21. Tonsil, lymph node and lymphoma tissue were used as positive controls. RESULTS: BCL10 nuclear positive cells were observed in focal lymphocytic infiltrates in the investigated minor salivary glands and were not restricted to patients with ectopic GCs. By double-staining, some of the BCL10 nuclear positive cells were identified as B cells. There was, however, no constitutive activation of NFkappaB as depicted by the exclusive cytoplasmic expression of p65 in the infiltrating lymphocytes in the pSS. CONCLUSION: Nuclear expression of BCL10 in infiltrating lymphocytes was a common occurrence in pSS minor salivary glands indicating it as a possible marker of autoimmune induced chronic inflammation. There was, however, no constitutive activation of NFkappaB.
20923710 Mechanotransduction and epigenetic control in autoimmune diseases. 2011 Jan Differentiation of epithelial cells is required to define tissue architecture and appropriate function of these cells is associated with a specific pattern of gene expression. DNA methylation, post-translational modification of histones and chromatin remodeling are nuclear mechanisms implicated in epigenetic control of gene expression. All factors relevant to tissue differentiation, including cell adhesion and shape, extracellular stimuli and transcriptional control, modulate gene expression and, thus, some of them are likely to impact on nuclear mechanisms of epigenetic control. The epithelial cells of salivary glands from Sjögren's syndrome patients display alterations in cell adhesion and shape. In this review, we summarize how these alterations are thought to lead to chromatin remodeling and, in doing so, bring about changes in transcriptional patterns. Additionally, we discuss how mechanotransduction in cells with impaired structural organization is implicated in modifying gene expression in these patients.
20184390 Non-infectious granulomatous diseases of the skin and their associated systemic diseases: 2010 Non-infectious granulomatous diseases of the skin are a broad group of distinct reactive inflammatory conditions that share important similarities. As a group, they are relatively difficult to diagnose and distinguish both clinically as well as histologically. Many of these disorders have significant associations with systemic diseases that impact the patient's overall prognosis. In this update, we offer a discussion of emerging concepts and controversies in this field, as presented through evidence-based answers to seven important clinical questions regarding palisading and epithelioid granulomata. These questions offer an opportunity to review ten non-infectious granulomatous conditions that have implications for systemic disease: granuloma annulare, annular elastolytic giant cell granuloma, necrobiosis lipoidica, methotrexate-induced accelerated rheumatoid nodulosis, necrobiotic xanthogranuloma, interstitial granulomatous dermatitis, interstitial granulomatous drug reaction, palisaded neutrophilic granulomatous dermatitis, sarcoidosis, and metastatic Crohn disease. Recent clinical, epidemiologic, and laboratory studies have shed some light on these diseases, the association of these conditions with systemic disorders, and their overall prognoses.
19168191 Intravenous immunoglobulin treatment for painful sensory neuropathy associated with Sjögr 2009 Apr 15 BACKGROUND: Patients with painful sensory neuropathy associated with Sjögren's syndrome-associated neuropathy often show severe neuropathic pain which is not relieved by conventional treatments. OBJECTIVE: To evaluate the effect of intravenous immunoglobulin (IVIg) therapy in the treatment of neuropathic pain associated with Sjögren's syndrome. PATIENTS AND METHODS: We examined 5 patients affected by painful sensory neuropathy associated with Sjögren's syndrome. All patients were treated with IVIg (0.4 g/kg/day for 5 days) and pain rating was assessed by the Visual Analogue Scale (VAS). RESULTS: All five patients showed a remarkable improvement in neuropathic pain following IVIg therapy. Pain, assessed by the determination of mean VAS score, was reduced by 73.4% from days 2-14 following treatment. The observed clinical improvement persisted for 2 to 6 months. One patient, examined by quantitative sensory testing (QST), showed an improvement of superficial sensory deficit accompanied by pain relief. CONCLUSION: IVIg might be an effective treatment for pain in Sjögren's syndrome-associated neuropathy. Further studies should be done in a controlled, blind study.
19212346 Melanoma inhibitor of apoptosis protein (ML-IAP) specific cytotoxic T lymphocytes cross-re 2009 Aug A large proportion of melanoma patients host a spontaneous T-cell response specifically against ML-IAP-derived peptides. In this study, we describe that some ML-IAP-specific cytotoxic T cells isolated from melanoma patients cross react with an epitope from the auto-antigen SS56. SS56 is a recently described target of autoantibody responses in Sjögren's syndrome (SS) as well as systemic lupus erythematosus (SLE). Here, we describe that SS56 is also an auto-antigen for T cells in SS and SLE. Hence, SS56-specific T cells could readily be detected in circulation and among the infiltrating cells of SLE skin lesions. SS56-specific T cells were able to lyse target cells presenting the peptide epitope on the surface. Notably, SS56-specific CD8 T cells isolated from an SS patient cross reacted with the ML-IAP epitope. This early evidence of a target for auto-reactive CTL in SS and SLE patients; it is to our knowledge previously unreported and underscores the important role of CD8 T cells in autoimmune disorders. Furthermore, the cross-reactivity against the auto-antigen SS56 and the tumor-antigen ML-IAP confirms the link between autoimmunity and anti-cancer cellular immune responses.
20126479 Spectral-domain optical coherence tomography and adaptive optics may detect hydroxychloroq 2009 Dec PURPOSE: To describe spectral-domain optical coherence tomography (SD-OCT) and adaptive optics (AO) imaging in hydroxychloroquine retinal toxicity. METHODS: Two patients with long-term hydroxychloroquine use, subtle perifoveal ophthalmoscopic pigmentary changes, and bilateral perifoveal defects on automated Humphrey visual field (HVF) 10-2 perimetry were imaged using SD-OCT and AO. RESULTS: SD-OCT images demonstrated loss of photoreceptor inner segment/outer segment (IS/OS) junction and a downward "sink-hole" displacement of inner retinal structures in areas of hydroxychloroquine toxicity corresponding to HVF 10-2 defects and ophthalmoscopic clinical examination findings. SD-OCT irregularities in the IS/OS junction were also seen in areas not detected on HVF 10-2. AO images showed disruption of the cone photoreceptor mosaic in areas corresponding to HVF 10-2 defects and SD-OCT IS/OS junction abnormalities. Additionally, irregularities in the cone photoreceptor density and mosaic were seen in areas with normal HVF 10-2 and SD-OCT findings. CONCLUSIONS: SD-OCT and AO detected abnormalities that correlate topographically with visual field loss from hydroxychloroquine toxicity as demonstrated by HVF 10-2 and may be useful in the detection of subclinical abnormalities that precede symptoms or objective visual field loss.
19688289 Anti-proteasome activator 28alpha is a novel anti-cytoplasmic antibody in patients with sy 2009 We evaluated the extent to which anti-proteasome activator (PA) 28alpha antibodies act as anti-cytoplasmic antibodies in systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). Sera from 46 SLE patients without SS, 11 SLE patients with SS, and 45 primary SS patients were tested. Using anti-PA28alpha and anti-PA28gamma (Ki) antibodies purified from nitrocellulose membranes onto which recombinant PA28alpha and Ki had been transferred, the cellular distributions of the targeted antigens were analyzed immunohistochemically. In addition, the incidence of anti-PA28alpha antibodies was compared with those of other anti-cytoplasmic antibodies. Immunofluorescent staining showed that purified anti-PA28alpha antibodies reacted with the cytoplasm of HEp-2 cells, whereas purified anti-Ki antibodies reacted with nucleoplasm. Among the 15 SLE patients without SS, the six SLE patients with SS, and the 30 primary SS patients who were anti-cytoplasmic-antibody positive, anti-SS-A/Ro antibodies were the most frequently detected (53, 67, and 70%, respectively); anti-PA28alpha antibodies were, respectively, detected in 33, 50, and 40% of those patient groups, incidences that were higher than those of anti-ribosomal P, anti-smooth muscle and anti-mitochondrial M2 antibodies. These results show that anti-PA28alpha antibodies are major anti-cytoplasmic antibodies in patients with SLE and SS, and the distinct cellular distributions of PA28alpha and Ki suggest these proteins are associated with different cellular functions.
19770713 High-frequency topical cyclosporine 0.05% in the treatment of severe dry eye refractory to 2009 Dec PURPOSE: The purpose of this study was to report the efficacy of topical cyclosporine 0.05% at a frequency of 3 to 4 times daily in severe dry eye disease. METHODS: We retrospectively identified a cohort of patients with severe dry eye disease who had shown inadequate response to at least a 4-month course of treatment with twice-daily use of topical cyclosporine 0.05% but who showed significant improvement to more frequent dosing. RESULTS: Twenty-two patients, including 13 patients with ocular graft-versus-host disease and 9 patients with primary or secondary Sjögren's syndrome, were included. After a minimum of a 2-month course of treatment with more frequent dosing of cyclosporine 0.05% (3 times a day in 7 patients and 4 times a day in 15 patients), overall dry eye symptoms were improved in 15 (68.2%) patients (9 patients with ocular graft-versus-host disease and 6 patients with Sjögren's syndrome). Mean corneal fluorescein staining scores (National Eye Institute scale of 0-15) improved (decreased) from the baseline (precyclosporine use) by -3.5 (range, 0 to -7) in patients with ocular graft-versus-host disease (P < or = 0.0008) and -2.8 (range, 0 to -5) in patients with Sjögren's syndrome (P < or = 0.001). After treatment with high-frequency use of cyclosporine 0.05%, the global physician assessment of dry eye status was favorable (improved) in 16 (72.7%) patients. Three (13.6%) patients reported new-onset symptoms of burning or irritation with the use of high-frequency dosing of topical cyclosporine. No other associated adverse effect was reported. CONCLUSION: These data suggest that patients with severe dry eye may require more frequent dosing of topical cyclosporine 0.05% than twice daily.
19745687 Hematologic manifestations and predictors of lymphoma development in primary Sjögren synd 2009 Sep The diverse hematologic manifestations of primary Sjögren syndrome (pSS) have not been systematically investigated, and their prognostic relevance remains unclear. We conducted a retrospective study of 536 consecutive patients followed in our institution to assess the prevalence of hematologic abnormalities and their associations with various disease manifestations in pSS. We also aimed to identify risk factors for the development of non-Hodgkin lymphoma (NHL) overall and by subtype. Anemia of chronic disease and hypergammaglobulinemia were the most prevalent hematologic manifestations encountered at diagnosis and during the course of pSS. Univariate analysis between cytopenias and glandular manifestations revealed a statistically significant correlation between lymphocytopenia and parotid gland enlargement (p = 0.002), as well as between neutropenia and xerostomia (p = 0.019). Anemia, lymphocytopenia, thrombocytopenia, hypergammaglobulinemia, the presence of monoclonal serum proteins, and cryoglobulinemia correlated significantly with the presence of extraglandular symptoms such as palpable purpura, lymphadenopathy, and splenomegaly. Lymphoma was diagnosed in 7.5% (95% confidence interval [CI], 5.4%-10%) of patients. Marginal zone B-cell lymphomas (MZBCLs) were the predominant histologic type (65%; 95% CI, 48.3%-79.4%), while diffuse large B-cell lymphomas (DLBCLs) accounted for 17.5% (95% CI, 7.3%-32.8%) of all cases. The development of NHL in patients with pSS could be predicted by the presence of simple clinical and laboratory factors at diagnosis: neutropenia (p = 0.041), cryoglobulinemia (p = 0.008), splenomegaly (p = 0.006), lymphadenopathy (p = 0.021), and low C4 levels (p = 0.009). Patients carrying any of these factors had a more than 5-fold increased risk of NHL compared to patients with no risk factors at all. The above set of disease characteristics could predict subsequent development of MZBCL; the presence of lymphocytopenia (p = 0.044) at diagnosis served as a risk factor for the development of a non-MZBCL, most commonly DLBCL. Anemia of chronic disease and hypergammaglobulinemia are common hematologic manifestations at diagnosis and during the course of pSS. Neutropenia and cryoglobulinemia at diagnosis are significantly associated with an increased risk of lymphoma development.
19364392 The minor salivary gland proteome in Sjögren's syndrome. 2009 Jul OBJECTIVE: To identify the global protein expression (the proteome) in the minor salivary glands from primary Sjögren's syndrome (pSS) patients and non-SS controls. MATERIALS AND METHODS: Minor labial salivary glands were obtained from six pSS patients and from six age-matched non-SS controls, lysed in SDS buffer and pooled into two groups, respectively. The lysates were analysed by liquid chromatography electrospray ionization combined with tandem mass spectrometry. Also, the proteins were separated by two-dimensional polyacrylamide gel electrophoresis and protein spots were subjected to mass spectrometry. RESULTS: Heat shock proteins, mucins, carbonic anhydrases, enolase, vimentin and cyclophilin B were among the proteins identified. The differences in the proteomes of minor salivary glands from pSS patients and non-SS controls were mainly related to ribosomal proteins, immunity and stress. Alpha-defensin-1 and calmodulin were among six proteins exclusively identified in pSS patients. CONCLUSION: We have identified several minor salivary gland proteins that may have implications for clarifying the SS pathophysiology. This experiment adds to the knowledge of proteins produced in salivary glands in health and disease, and may form the basis of further studies on biomarkers of prognostic and diagnostic value.
21189220 Bromodomain coactivators in cancer, obesity, type 2 diabetes, and inflammation. 2010 Dec Double bromodomain proteins bind to acetylated lysines in histones, bringing associated histone modification and nucleosome remodeling activity to chromatin. The ability of bromodomain regulators to alter chromatin status and control gene expression has long been appreciated to be important in the development of certain human cancers. However, bromodomain proteins have now been found also to be critical, non-redundant players in diverse, non-malignant phenotypes, directing transcriptional programs that control adipogenesis, energy metabolism and inflammation. The fact that such different processes are functionally linked by the same molecular machinery suggests a common epigenetic basis to understand and interpret the origins of several important co-morbidities, such as asthma or cancer that occurs in obesity, and complex inflammatory diseases like cardiovascular disease, systemic lupus erythematosus, rheumatoid arthritis and insulin resistance that may be built on a common pro-inflammatory foundation.
20980463 Interleukin-1β produced in response to islet autoantigen presentation differentiates T-he 2011 Jan OBJECTIVE: The effectiveness of tolerizing immunotherapeutic strategies, such as anti-CD40L or dendritic cells (DCs), is greater when administered to young nonobese diabetic (NOD) mice than at peak insulitis. RelB(lo) DCs, generated in the presence of an nuclear factor-κB inhibitor, induce T-regulatory (Treg) cells and suppress inflammation in a model of rheumatoid arthritis. Interleukin (IL)-1β is overexpressed in humans and mice at risk of type 1 diabetes, dysregulates Treg cells, and accelerates diabetes in NOD mice. We investigated the relationship between IL-1β production and the response to RelB(lo) DCs in the prediabetic period. RESEARCH DESIGN AND METHODS: We injected RelB(lo) DCs subcutaneously into 4- or 14-week-old NOD mice and tracked the incidence of diabetes and effect on Treg cell function. We measured the expression of proinflammatory cytokines by stimulated splenocytes and unstimulated islets from mice of different ages and strains and proliferative and cytokine responses of T effectors to Treg in vitro. RESULTS: Tolerizing RelB(lo) DCs significantly inhibited diabetes progression when administered to 4-week-old but not 14-week-old mice. IL-1β production by NOD splenocytes and mRNA expression by islets increased from 6 to 16 weeks of age when major histocompatibility complex (MHC)-restricted islet antigen presentation to autoreactive T-cells occurred. IL-1 reduced the capacity of Treg cells to suppress effector cells and promoted their conversion to Th17 cells. RelB(lo) DCs exacerbated the IL-1-dependent decline in Treg function and promoted Th17 conversion. CONCLUSIONS: IL-1β, generated by islet-autoreactive cells in MHC-susceptible mice, accelerates diabetes by differentiating Th17 at the expense of Treg. Tolerizing DC therapies can regulate islet autoantigen priming and prevent diabetes, but progression past the IL-1β/IL-17 checkpoint signals the need for other strategies.
20642015 Cy5-Tat-Glu-Pro-Asp-acyloxymethyl ketone. 2004 Caspases are a group of cysteine proteases, which exist within cells as inactive zymogens, and are cleaved to form active enzymes after induction of apoptosis (1-3). There are two major pathways through which caspases are activated. One is the death signal–induced, death receptor–mediated extrinsic pathway, and the other is the stress-induced, mitochondria-directed intrinsic pathway (3, 4). Caspases convey the apoptotic signal in a proteolytic cascade, with caspases cleaving and activating other caspases. Caspase-8 and -9 act as initiators at the upper stream of this cascade, while caspase-3, -6, and -7 work as downstream executioners (1, 3, 4). Although physiological apoptosis takes place during embryonic development and in adult homeostasis, excessive apoptosis has been observed in some human diseases such as myocardial infarction, rheumatoid arthritis, ischemia, transplant rejection, and neurodegenerative disorders (Parkinson's and Alzheimer's) (5, 6). On the contrary, evading apoptosis is a hallmark of human cancer (7, 8). Many different molecular probes have been developed for imaging apoptosis both at the cellular level and in vivo (2, 5, 7, 9, 10). Of them, a large number of the probes are annexin V–based. Annexin V is a 36-kDa protein that binds to externalized phosphatidylserine residues in the presence of calcium ions on the surface of apoptotic cells (5). Radiolabeled annexin V derivatives have already been used for clinical imaging in many diseases, most notably for imaging myocardial dysfunction. A drawback of annexin V–based probes is their low specificity to apoptotic cells. Annexin V cannot distinguish apoptosis from necrosis (5). Phosphatidylserine externalization is also associated with inflammation and platelet activation, causing further challenges with annexin V specificity. During recent years, much work has focused on the development of probes for caspase-3 and -7. Thornberry et al. have observed that most caspases prefer a tetrapeptide motif with an aspartyl residue at P4 (11). Asp-Glu-Val-Asp (DEVD) is the peptide sequence optimal for caspase-3 and -7, while the Val-Glu-His-Asp (VEHD) sequence is preferred by caspase-6 (5). These sequence-based probes demonstrate high caspase specificity; however, most probes suffer from poor cellular uptake in the intact cell, a requirement for early detection. Edgington et al. developed a class of probes based on the acyloxymethyl ketone (AOMK) and the optimal sequence of caspase-3 and -7 (2). AB50-Cy5 is one of the probes, which contains a Glu-Pro-Asp-AOMK sequence labeled with the Cy5 fluorophore. This probe showed labeling of caspase-3 and legumain with no detectable cathepsin B labeling. To enhance the cell permeability of AB50-Cy5, the investigators synthesized the probe tAB50-Cy5, a version of the probe containing a tat peptide. For this probe, the tat peptide was used to increase the cell uptake of the probe through multiple positively charged amino acids, while AOMK was used to label caspases. This chapter summarized the synthesis and comparative analysis of tAB50-Cy5 and AB50-Cy5.
20469888 Substrate specificity and kinetic studies of PADs 1, 3, and 4 identify potent and selectiv 2010 Jun 15 Protein citrullination has been shown to regulate numerous physiological pathways (e.g., the innate immune response and gene transcription) and is, when dysregulated, known to be associated with numerous human diseases, including cancer, rheumatoid arthritis, and multiple sclerosis. This modification, also termed deimination, is catalyzed by a group of enzymes called the protein arginine deiminases (PADs). In mammals, there are five PAD family members (i.e., PADs 1, 2, 3, 4, and 6) that exhibit tissue-specific expression patterns and vary in their subcellular localization. The kinetic characterization of PAD4 was recently reported, and these efforts guided the development of the two most potent PAD4 inhibitors (i.e., F- and Cl-amidine) known to date. In addition to being potent PAD4 inhibitors, we show here that Cl-amidine also exhibits a strong inhibitory effect against PADs 1 and 3, thus indicating its utility as a pan PAD inhibitor. Given the increasing number of diseases in which dysregulated PAD activity has been implicated, the development of PAD-selective inhibitors is of paramount importance. To aid that goal, we characterized the catalytic mechanism and substrate specificity of PADs 1 and 3. Herein, we report the results of these studies, which suggest that, like PAD4, PADs 1 and 3 employ a reverse protonation mechanism. Additionally, the substrate specificity studies provided critical information that aided the identification of PAD3-selective inhibitors. These compounds, denoted F4- and Cl4-amidine, are the most potent PAD3 inhibitors ever described.
19947069 Characteristics of patients with chronic pain accessing treatment with medical cannabis in 2009 Sep OBJECTIVES: This study was conducted to better understand the characteristics of chronic pain patients seeking treatment with medicinal cannabis (MC). DESIGN: Retrospective chart reviews of 139 patients (87 males, median age 47 years; 52 females, median age 48 years); all were legally qualified for MC use in Washington State. SETTING: Regional pain clinic staffed by university faculty. INCLUSION CRITERIA: age 18 years and older; having legally accessed MC treatment, with valid documentation in their medical records. All data were de-identified. MAIN OUTCOME MEASURES: Records were scored for multiple indicators, including time since initial MC authorization, qualifying condition(s), McGill Pain score, functional status, use of other analgesic modalities, including opioids, and patterns of use over time. RESULTS: Of 139 patients, 15 (11 percent) had prior authorizations for MC before seeking care in this clinic. The sample contained 236.4 patient-years of authorized MC use. Time of authorized use ranged from 11 days to 8.31 years (median of 1.12 years). Most patients were male (63 percent) yet female patients averaged 0.18 years longer authorized use. There were no other gender-specific trends or factors. Most patients (n = 123, 88 percent) had more than one pain syndrome present. Myofascial pain syndrome was the most common diagnosis (n = 114, 82 percent), followed by neuropathic pain (n = 89, 64 percent), discogenic back pain (n = 72, 51.7 percent), and osteoarthritis (n = 37, 26.6 percent). Other diagnoses included diabetic neuropathy, central pain syndrome, phantom pain, spinal cord injury, fibromyalgia, rheumatoid arthritis, HIV neuropathy, visceral pain, and malignant pain. In 51 (37 percent) patients, there were documented instances of major hurdles related to accessing MC, including prior physicians unwilling to authorize use, legal problems related to MC use, and difficulties in finding an affordable and consistent supply of MC. CONCLUSIONS: Data indicate that males and females access MC at approximately the same rate, with similar median authorization times. Although the majority of patient records documented significant symptom alleviation with MC, major treatment access and delivery barriers remain.
19830703 Impediment of NEMO oligomerization inhibits osteoclastogenesis and osteolysis. 2009 Dec 15 The transcription factor NF-kappaB is essential for osteoclastogenesis and is considered an immune-modulator of rheumatoid arthritis and inflammatory osteolysis. Activation of NF-kappaB subunits is regulated by the upstream IkappaB kinase (IKK) complex which contains IKKalpha, IKKbeta, and IKKgamma; the latter also known as NF-kappaB essential modulator (NEMO). The role of IKKalpha and IKKbeta in the skeletal development and inflammatory osteolysis has been described, whereas little is known regarding the role of NEMO in this setting. Typically, signals induced by RANK ligand (RANKL) or TNF prompt oligomerization of NEMO monomers through the coiled-coil-2 (CC2) and leucine zipper (LZ) motifs. This step facilitates binding to IKKs and further relaying signal transduction. Given the central role of NF-kappaB in osteoclastogenesis, we asked whether NEMO is essential for osteoclastogenesis and whether interruption of NEMO oligomerization impedes osteoclast differentiation in vitro and in vivo. Using cell-permeable short peptides overlapping the CC2 and LZ motifs we show that these peptides specifically bind to NEMO monomers, prevent trimer formation, and render NEMO monomers susceptible for ubiquitin-mediated degradation. Further, CC2 and LZ peptides attenuate RANKL- and TNF-induced NF-kappaB signaling in bone marrow-derived osteoclast precursors (OCPs). More importantly, these peptides potently inhibit osteoclastogenesis, in vitro, and arrest RANKL-induced osteolysis, in mice. To further ascertain its role in osteoclastogenesis, we were able to block osteoclastogenesis using NEMO siRNA knockdown approach. Collectively, our data establish that obstruction of NEMO oligomerization destabilizes NEMO monomers, inhibits NF-kappaB activation, impedes osteoclastogenesis and arrests inflammatory osteolysis. Thus, NEMO presents itself as a promising target for anti-osteolytic intervention.
19797564 Diagnostic utility of cytokine biomarkers in the evaluation of acute knee pain. 2009 Oct BACKGROUND: The diagnosis of clinically important meniscal tears of the knee remains challenging, and it is unknown why only some injuries become painful. The role of inflammatory cytokines in generating pain following meniscal injury remains unclear. This study aimed to investigate the cytokine profile in patients with acute knee pain believed to be secondary to meniscal damage. METHODS: This prospective cohort study included thirty-two patients without rheumatoid arthritis who had knee pain for less than six months, with either an acute or insidious onset, and elected to have arthroscopic treatment after nonoperative management had failed. Twenty-three of these patients elected to have the contralateral, nonoperatively treated knee lavaged at the time of arthroscopy. Fifteen asymptomatic control subjects also contributed samples of knee joint fluid, for a total of seventy samples from forty-seven subjects. Lavage of the operatively treated, contralateral, and control knees was performed with the patient under regional anesthesia prior to arthroscopy, if applicable, by the infusion of sterile saline solution into the knee followed by the immediate withdrawal into a syringe. The concentrations of seventeen inflammatory cytokines and chemokines were measured with use of a multiplexed immunoassay panel. Preoperative magnetic resonance imaging findings and cytokine assay results were compared with intraoperative findings. RESULTS: Multivariate analysis of variance detected significantly greater concentrations of interferon gamma (IFN-gamma); interleukins 2, 4, 6, 10, and 13 (IL-2, IL-4, IL-6, IL-10, and IL-13); monocyte chemotactic protein-1 (MCP-1); and macrophage inflammatory protein-1 beta (MIP-1beta) in fluid samples from painful knees than in samples from nonpainful knees. Correlation analysis demonstrated a significant positive correlation between patient-reported pain scores and concentrations of IL-6 (Spearman rho = 0.7), MCP-1 (rho = 0.8), MIP-1beta (rho = 0.6), and IFN-gamma (rho = 0.6). These four cytokines also demonstrated a positive correlation with each other (rho = 0.5 to 0.7). The presence of IFN-gamma, IL-6, MCP-1, or MIP-1beta performed as well as magnetic resonance imaging in the prediction of intraoperative findings. CONCLUSIONS: Intra-articular concentrations of four inflammatory cytokines IFN-gamma, IL-6, MCP-1, and MIP-1beta correlated to pain in patients with symptomatic meniscal tears in the knee but were markedly lower in asymptomatic normal knees and in asymptomatic knees with meniscal tears. These cytokines may be involved in the generation of pain following meniscal injury.