240 research outputs found
Kimura's Disease
Kimuras disease is a chronic inflammatory disorder of unknown etiology. It is rare in the West, but endemic in Asia. It typically presents as solitary or multiple subcutaneous nodules, that slowly increase in size. The lesions are variably painful and pruritic. It often accompanied by regional lymphadenopathy, raised serum eosinophil counts, and markedly elevated serum immunoglobulin E levels. Histologically, the lesions are characterized by reactive lymphoid follicles with eosinophilic infiltration and an increased amount of postcapillary venules. The optimal treatment for KD remains controversial. Although the condition seldom resolves spontaneously, malignant transformation has not been reported to date, and the prognosis is good. We describe a male patient with a 4-year pruritic progressive “bump” in front of his left ear. On physical examination, the patient had 2 discrete lesions on the left side of his face near his ear. Postauricularly, there was a 3 × 5
cm erythematous to violaceous, indurated nodule. Preauricularly, there was a similar, but smaller cyst-like nodule. Punch biopsy showed a superficial and deep nodular and interstitial infiltrate, reactive lymphoid follicles with a dense infiltration of eosinophils and areas of eosinophilic follicle lysis. The patient received intralesional triamcinolone acetonide injections 10 mg/cc behind left ear with a good improvement
The Effect of Doxycycline on PMA-Induced MUC5B Expression via MMP-9 and p38 in NCI-H292 Cells
ObjectivesDoxycycline is commonly used in medicine for its bacteriostatic antimicrobial properties. Recent studies have reported that doxycycline also has anti-inflammatory effects. Matrix metalloproteinase (MMP)-9 has been found to be involved in the physiological and pathological process of inflammatory airway disease. Phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, is known to stimulate the expression of MMP and mucin genes in the airway and intestinal epithelial cells. Therefore, the effects and signal pathways of doxycycline on PMA-induced MUC5B expression dependent MMP-9 in human airway epithelial cells were investigated.MethodsIn human NCI-H292 airway epithelial cells, MUC5B and MMP-9 mRNA expression, MUC5B protein expression, and MMP-9 protein activity after the treatment with PMA, MMP-9 or doxycycline were determined by reverse transcriptase-polymerase chain reaction, enzyme immunoassay, gelatin zymography, and Western blot analysis.ResultsPMA increased MMP-9 and MUC5B expression. MMP-9 increased MUC5B expression. Doxycycline inhibited PMA-induced MUC5B expression, and PMA-induced MMP-9 mRNA expression and protein activity. Doxycycline inhibited phosphorylation of p38 induced by PMA and MMP-9.ConclusionThe results of this study suggest that doxycycline inhibited PMA-induced MUC5B mRNA expression and protein production through the MMP-9 and p38 pathways in human NCI-H292 airway epithelial cells
Minocycline-induced hypersensitivity syndrome presenting with meningitis and brain edema: a case report
<p/> <p>Background</p> <p>Hypersentivity Syndrome (HS) may be a life-threatening condition. It frequently presents with fever, rash, eosinophilia and systemic manifestations. Mortality can be as high as 10% and is primarily due to hepatic failure. We describe what we believe to be the first case of minocycline-induced HS with accompanying lymphocytic meningitis and cerebral edema reported in the literature.</p> <p>Case presentation</p> <p>A 31-year-old HIV-positive female of African origin presented with acute fever, lymphocytic meningitis, brain edema, rash, eosinophilia, and cytolytic hepatitis. She had been started on minocycline for inflammatory acne 21 days prior to the onset of symptoms. HS was diagnosed clinically and after exclusion of infectious causes. Minocycline was withdrawn and steroids were administered from the second day after presentation because of the severity of the symptoms. All signs resolved by the seventh day and steroids were tailed off over a period of 8 months.</p> <p>Conclusion</p> <p>Clinicians should maintain a high index of suspicion for serious adverse reactions to minocycline including lymphocytic meningitis and cerebral edema among HIV-positive patients, especially if they are of African origin. Safer alternatives should be considered for treatment of acne vulgaris. Early recognition of the symptoms and prompt withdrawal of the drug are important to improve the outcome.</p
Unexpected effect of a Bacteroides conjugative transposon, CTnDOT, on chromosomal gene expression in its bacterial host
Foreign DNA elements such as plasmids and conjugative transposons are constantly entering new bacterial hosts. A possible outcome of such events that has not been considered previously is that regulatory genes carried on some of them might affect the expression of chromosomal genes of the new host. To assess this possibility, we investigated the effect of the Bacteroides conjugative transposon CTnDOT on expression of chromosomal genes in Bacteroides thetaiotaomicron 5482 (BT4001). Most of the upregulated genes were genes of unknown function, but a number of them were associated with a region of the chromosome that contained a putative conjugative transposon, which had been tentatively designated as CTn4-bt. Upregulation of CTn4-bt genes and other chromosomal genes affected by CTnDOT was controlled by two regulatory genes on CTnDOT, rteA and rteB, which encode a two-component regulatory system. Transfer of CTn4-bt was also mediated by rteA and rteB. Three other putative CTns, CTn1-bt, CTn2-bt and CTn3-bt, were mobilized by CTnERL, a CTn closely related to CTnDOT, but genes from CTnERL other than rteA and rteB were also required. Unexpectedly, homologous recombination was required for CTn1-bt, CTn2-bt, CTn3-bt and CTn4-bt to integrate in the recipient. Our results show that regulatory genes on an incoming mobile element can have multiple effects on its new host, including the activation of previously non-transmissible elements
Activator protein-1 (AP-1) signalling in human atherosclerosis: results of a systematic evaluation and intervention study
Animal studies implicate the AP-1 (activator protein-1) pro-inflammatory pathway as a promising target in the treatment of atherosclerotic disease. It is, however, unclear whether these observations apply to human atherosclerosis. Therefore we evaluated the profile of AP-1 activation through histological analysis and tested the potential benefit of AP-1 inhibition in a clinical trial. AP-1 activation was quantified by phospho-c-Jun nuclear translocation (immunohistochemistry) on a biobank of aortic wall samples from organ donors. The effect of AP-1 inhibition on vascular parameters was tested through a double blind placebo-controlled cross-over study of 28 days doxycycline or placebo in patients with symptomatic peripheral artery disease. Vascular function was assessed by brachial dilation as well as by plasma samples analysed for hs-CRP (high-sensitivity C-reactive protein), IL-6 (interleukin-6), IL-8, ICAM-1 (intercellular adhesion molecule-1), vWF (von Willebrand factor), MCP-1 (monocyte chemoattractant protein-1), PAI-1 (plasminogen activator inhibitor-1) and fibrinogen. Histological evaluation of human atherosclerosis showed minimal AP-1 activation in non-diseased arterial wall (i.e. vessel wall without any signs of atherosclerotic disease). A gradual increase of AP-1 activation was found in non-progressive and progressive phases of atherosclerosis respectively (P<0.044). No significant difference was found between progressive and vulnerable lesions. The expression of phospho-c-Jun diminished as the lesion stabilized (P<0.016) and does not significantly differ from the normal aortic wall (P<0.33). Evaluation of the doxycycline intervention only revealed a borderline-significant reduction of circulating hs-CRP levels (−0.51 μg/ml, P=0.05) and did not affect any of the other markers of systemic inflammation and vascular function. Our studies do not characterize AP-1 as a therapeutic target for progressive human atherosclerotic disease
Dietary magnesium, not calcium, prevents vascular calcification in a mouse model for pseudoxanthoma elasticum
Pseudoxanthoma elasticum (PXE) is a heritable disorder characterized by ectopic calcification of connective tissue in skin, Bruch’s membrane of the eye, and walls of blood vessels. PXE is caused by mutations in the ABCC6 gene, but the exact etiology is still unknown. While observations on patients suggest that high calcium intake worsens the clinical symptoms, the patient organization PXE International has published the dietary advice to increase calcium intake in combination with increased magnesium intake. To obtain more data on this controversial issue, we examined the effect of dietary calcium and magnesium in the Abcc6−/− mouse, a PXE mouse model which mimics the clinical features of PXE. Abcc6−/− mice were placed on specific diets for 3, 7, and 12 months. Disease severity was measured by quantifying calcification of blood vessels in the kidney. Raising the calcium content in the diet from 0.5% to 2% did not change disease severity. In contrast, simultaneous increase of both calcium (from 0.5% to 2.0%) and magnesium (from 0.05% to 0.2%) slowed down the calcification significantly. Our present findings that increase in dietary magnesium reduces vascular calcification in a mouse model for PXE should stimulate further studies to establish a dietary intervention for PXE
Population Genetic Analysis of Propionibacterium acnes Identifies a Subpopulation and Epidemic Clones Associated with Acne
The involvement of Propionibacterium acnes in the pathogenesis of acne is controversial, mainly owing to its dominance as an inhabitant of healthy skin. This study tested the hypothesis that specific evolutionary lineages of the species are associated with acne while others are compatible with health. Phylogenetic reconstruction based on nine housekeeping genes was performed on 210 isolates of P. acnes from well-characterized patients with acne, various opportunistic infections, and from healthy carriers. Although evidence of recombination was observed, the results showed a basically clonal population structure correlated with allelic variation in the virulence genes tly and camp5, with pulsed field gel electrophoresis (PFGE)- and biotype, and with expressed putative virulence factors. An unexpected geographically and temporal widespread dissemination of some clones was demonstrated. The population comprised three major divisions, one of which, including an epidemic clone, was strongly associated with moderate to severe acne while others were associated with health and opportunistic infections. This dichotomy correlated with previously observed differences in in vitro inflammation-inducing properties. Comparison of five genomes representing acne- and health-associated clones revealed multiple both cluster- and strain-specific genes that suggest major differences in ecological preferences and redefines the spectrum of disease-associated virulence factors. The results of the study indicate that particular clones of P. acnes play an etiologic role in acne while others are associated with health
Mucopolysaccharidosis type II (Hunter syndrome): a clinical review and recommendations for treatment in the era of enzyme replacement therapy
Mucopolysaccharidosis type II (MPS II; Hunter syndrome) is a rare X-linked recessive disease caused by deficiency of the lysosomal enzyme iduronate-2-sulphatase, leading to progressive accumulation of glycosaminoglycans in nearly all cell types, tissues and organs. Clinical manifestations include severe airway obstruction, skeletal deformities, cardiomyopathy and, in most patients, neurological decline. Death usually occurs in the second decade of life, although some patients with less severe disease have survived into their fifth or sixth decade. Until recently, there has been no effective therapy for MPS II, and care has been palliative. Enzyme replacement therapy (ERT) with recombinant human iduronate-2-sulphatase (idursulfase), however, has now been introduced. Weekly intravenous infusions of idursulfase have been shown to improve many of the signs and symptoms and overall wellbeing in patients with MPS II. This paper provides an overview of the clinical manifestations, diagnosis and symptomatic management of patients with MPS II and provides recommendations for the use of ERT. The issue of treating very young patients and those with CNS involvement is also discussed. ERT with idursulfase has the potential to benefit many patients with MPS II, especially if started early in the course of the disease
Critical data-based re-evaluation of minocycline as a putative specific microglia inhibitor.
Minocycline, a second generation broad-spectrum antibiotic, has been frequently postulated to be a "microglia inhibitor." A considerable number of publications have used minocycline as a tool and concluded, after achieving a pharmacological effect, that the effect must be due to "inhibition" of microglia. It is, however, unclear how this "inhibition" is achieved at the molecular and cellular levels. Here, we weigh the evidence whether minocycline is indeed a bona fide microglia inhibitor and discuss how data generated with minocycline should be interpreted. GLIA 2016;64:1788-1794
Molecular Effects of Doxycycline Treatment on Pterygium as Revealed by Massive Transcriptome Sequencing
Pterygium is a lesion of the eye surface which involves cell proliferation, migration, angiogenesis, fibrosis, and extracellular matrix remodelling. Surgery is the only approved method to treat this disorder, but high recurrence rates are common. Recently, it has been shown in a mouse model that treatment with doxycycline resulted in reduction of the pterygium lesions. Here we study the mechanism(s) of action by which doxycycline achieves these results, using massive sequencing techniques. Surgically removed pterygia from 10 consecutive patients were set in short term culture and exposed to 0 (control), 50, 200, and 500 µg/ml doxycycline for 24 h, their mRNA was purified, reverse transcribed and sequenced through Illumina’s massive sequencing protocols. Acquired data were subjected to quantile normalization and analyzed using cytoscape plugin software to explore the pathways involved. False discovery rate (FDR) methods were used to identify 332 genes which modified their expression in a dose-dependent manner upon exposure to doxycycline. The more represented cellular pathways included all mitochondrial genes, the endoplasmic reticulum stress response, integrins and extracellular matrix components, and growth factors. A high correlation was obtained when comparing ultrasequencing data with qRT-PCR and ELISA results
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