Th2 cytokines, IgE and mast cells play a crucial role in the induction of para-phenylenediamine-induced contact hypersensitivity in mice

We previously reported the establishment of a mouse model system of contact hypersensitivity (CHS) to paraphenylemediamine (PPD). In order to analyse the functional contribution of Th2 cytokines, IL-4 and IL-5, in PPD induced CHS, STAT6 deficient (STAT6(–/–)) and wild-type control (WT) mice (C57BL/6) were immunized by the topical application of a PPD solution, and then the subsequent skin reactions were examined. Ear swelling was significantly reduced with a delayed peak response in STAT6(–/–) mice as compared with that of WT mice. A histological analysis showed the infiltration of both eosinophils and neutrophils in the skin of STAT6(–/–) mice challenged 24 h previously to significantly decrease in comparison with that in the WT mice. The expression of Th2 cytokines (IL-4, IL-5) by ELISA in the PPD-challenged skin tissue specimens as well as the IgE and IgG1 response after challenge were also profoundly reduced in the STAT6(–/–) mice. The adoptive transfer of the serum obtained from sensitized WT mice for the putative IgE transfer induced a peak response at 3 h and 24 h after challenge. To further investigate the role of mast cells in the induction of PPD-CHS, mast cell deficient W/W(v) mice were sensitized with PPD and then were challenged. Maximal ear swelling was detected from 12 to 24 h and another small peak response was observed at 1 h in+/+mice, whereas only a small peak response at 24 h was detected in W/W(v) mice. These data indicate that not only Th2 cytokines and IgE but also mast cells play an essential role in the induction of PPD-CHS

Evaluation of 3D heads-up vitrectomy: outcomes of psychometric skills testing and surgeon satisfaction

OBJECTIVES: To evaluate the use of a three-dimensional heads-up microscope (3DM) during 25-gauge pars plana vitrectomy (PPV) compared with a traditional ophthalmic microscope (TM) in terms of efficacy, safety, and teaching and learning satisfaction. METHODS: Prospective comparative interventional study. Fifty eyes affected by one of the following diseases: rhegmatogenous or tractional retinal detachment, epiretinal membrane, full-thickness macular hole, vitreous hemorrhage, or dropped lens. The 50 eyes were randomly assigned to one of two groups: group A (25 eyes) underwent 25-gauge PPV with 3DM, and group B (25 eyes) underwent 25-gauge PPV with TM. The main outcome measures were the duration of the operation, intraoperative complications, and surgeon and observer satisfaction. A questionnaire was used to assess surgeon satisfaction according to the following parameters: comfort, visibility, image quality, depth perception, simplicity of use, maneuverability, and teaching. A questionnaire to assess observer satisfaction was completed by 20 observers (surgical residents or ophthalmic surgeons). RESULTS: The degree of satisfaction was higher using 3DM for both surgeons and observers (P < 0.001). The average duration of the operation did not differ significantly between the two methods. No major complications occurred for either method. CONCLUSIONS: PPV with 3DM is more comfortable for the surgeon and poses no substantially greater risk of complications for the patient. The high-definition screen delivers excellent depth perception and better screen parameter control, which results in high-quality surgical performance. 3DM surgery helps to significantly improve teaching and learning intra-operative surgical procedure

A prospective study of the adaptive changes in the gut microbiome during standard-of-care chemoradiotherapy for gynecologic cancers.

BackgroundA diverse and abundant gut microbiome can improve cancer patients' treatment response; however, the effect of pelvic chemoradiotherapy (CRT) on gut diversity and composition is unclear. The purpose of this prospective study was to identify changes in the diversity and composition of the gut microbiome during and after pelvic CRT.Materials and methodsRectal swabs from 58 women with cervical, vaginal, or vulvar cancer from two institutions were prospectively analyzed before CRT (baseline), during CRT (weeks 1, 3, and 5), and at first follow-up (week 12) using 16Sv4 rRNA gene sequencing of the V4 hypervariable region of the bacterial 16S rRNA marker gene. 42 of these patients received antibiotics during the study period. Observed operational taxonomic units (OTUs; representative of richness) and Shannon, Simpson, Inverse Simpson, and Fisher diversity indices were used to characterize alpha (within-sample) diversity. Changes over time were assessed using a paired t-test, repeated measures ANOVA, and linear mixed modeling. Compositional changes in specific bacteria over time were evaluated using linear discriminant analysis effect size.ResultsGut microbiome richness and diversity levels continually decreased throughout CRT (mean Shannon diversity index, 2.52 vs. 2.91; all P ConclusionAfter CRT, the diversity of the gut microbiomes in this population tended to return to baseline levels by the 12 week follow-up period, but structure and composition remained significantly altered. These changes should be considered when designing studies to analyze the gut microbiome in patients who receive pelvic CRT for gynecologic cancers