Comparative assessment of gut microbial composition and function in patients with Graves' disease and Graves' orbitopathy.

BACKGROUND: A previous study indicated that gut microbiota changed notably in Graves' orbitopathy (GO) patients as compared to controls. However, the characteristics of intestinal bacteria in Graves' disease (GD) and GO are unclear. OBJECTIVE: The present study aimed to identify specific intestinal bacteria of GD and GO, respectively. METHODS: The gut microbial communities of the fecal samples of 30 GD patients without GO, 33 GO subjects, and 32 healthy subjects were analyzed and compared by 16S rRNA gene sequencing. RESULTS: At the phylum level, the proportion of Deinococcus-Thermus and Chloroflexi was decreased significantly in GO patients as compared to GD. At the genus level, the proportion of Subdoligranulum and Bilophila was increased while that of Blautia, Anaerostipes, Dorea, Butyricicoccus, Romboutsia, Fusicatenibacter, unidentified_ Lachnospiraceae, unidentified_Clostridiales, Collineslla, Intestinibacter, and Phascolarctobacterium was decreased in the GO group as compared to the GD group. Random forest analysis was used for the identification of specific intestinal microbiota, and Deinococcus-Thermus, Cyanobacteria and Chloroflexi were ranked in the top ten according to their contributions to sample classification. Moreover, compared to the control, there were multiple gut bacterial enrichment metabolic pathways in GO and GD patients, including nucleotide metabolism, enzyme family, and energy metabolism. Compared to GO, the only enrichment metabolic pathway found in GD was the viral protein family. CONCLUSIONS: This study highlighted the significant differences in the intestinal microbiota and predictive functions of GD with GO, thereby providing new insights into the role of the gut bacteria that might contribute to the development of GO in GD patients.

Improved, low-cost methods for pancreatic islet purification in rats.

OBJECTIVE: Density gradient separation of islets from exocrine tissue is usually performed using Ficoll. However, this reagent significantly increases the cost of isolation. The aim of the present study was to investigate the effects on islet preparations of purification methods using Lymphoprep and Iodixanol (OptiPrep) density gradients. METHODS: Pancreata were procured from 46 Wistar rats, loaded with collagenase V (Sigma), and mechanically dissociated using standard procedures. After the digestion phase, the islets purified by 3 methods-Ficoll, Lymphoprep, and Iodixanol (OptiPrep)-were assessed for yields, purity, morphology, and in vitro function. RESULT: We expressed the yields as islet equivalents (IEQ, diameter standardizing to 150 microm), showing no significant differences. Compared with the Ficoll group, the purity was significantly higher in the Lymphoprep (P = .005) and Iodixanol (OptiPrep) groups (P = .011). While the viability was >90% in all 3 groups, the viability in the Lymphoprep Group and OptiPrep groups was significantly higher than that of the Ficoll group (P < .001). In vitro islet function did not differ among the 3 experimental groups. CONCLUSION: Lymphoprep and Iodixanol were as effective as Ficoll in terms of islet yield and in vitro function. High-purity and high-viability islet cells were obtained using improved Lymphoprep-based or Iodixanol (OptiPrep)-based density gradient methods, potential low-cost substitutes for Ficoll.

Clinical improvement and immunohistochemical findings in severe atopic dermatitis treated with interferon gamma.

BACKGROUND: Several clinical studies have focused on the therapeutic effects of interferon gamma (IFN-gamma) in patients with severe atopic dermatitis (AD), although the dosage of recombinant IFN-gamma (rIFN-gamma), therapeutic schedule, and the degree of clinical improvement were different among studies. Although the exact mechanism of action of IFN-gamma therapy in AD is not clear, the beneficial effects of IFN-gamma have been attributed mainly to an immunomodulating effect on the expression of certain immunologic markers. OBJECTIVE: Our purpose was to study the therapeutic effect of two different dosages of rIFN-gamma on AD and to investigate the change of lesional expression of infiltrating inflammatory cell markers associated with rIFN-gamma therapeutic efficacy. METHODS: Fifty-one patients with severe recalcitrant AD were treated with rIFN-gamma. Twenty patients were treated with 0.5 x 10(6) IU/m(2) of rIFN-gamma (low-dose [LD] group); 21 patients received 1.5 x 10(6) IU/m(2) of rIFN-gamma (high-dose [HD] group); and 10 patients received placebo. The patients were injected subcutaneously 3 times a week for 12 weeks. Immunohistochemical study was performed in 20 patients of the HD group in the initial visit and after completion of rIFN-gamma therapy with a panel of 14 monoclonal antibodies as markers of inflammatory cells and cytokines. RESULTS: The disease severity of the 2 groups treated with rIFN-gamma was reduced significantly at the end of treatment compared with that of the placebo group (P<.05). More rapid clinical improvement and more effective treatment outcome were seen in the HD group than in the LD group for the initial 6-week treatment period; however, the clinical improvement in both of the treated groups was stable and maintained after week 8 of treatment. Immunohistochemical findings showed statistically significant reduction in the lesional expression of CD25 and EG2 cells that infiltrated into skin after rIFN-gamma therapy. CONCLUSION: This study demonstrated that rIFN-gamma therapy for AD is safe and effective. In the early phase of therapy, a higher dosage of rIFN-gamma is more effective; and for the maintenance of clinical improvement, a lower dosage of rIFN-gamma is recommended when high cost and effectiveness of rIFN-gamma are considered. The therapeutic efficacy of rIFN-gamma in AD might be in part related to the decreased number of CD25(+) and EG2(+) inflammatory cells infiltrated into skin.