Microbiomics of irrigation with xylitol or Lactococcus lactis in chronic rhinosinusitis.

OBJECTIVE: Topical sinonasal rinse therapies may alter the local microbiome and improve disease control in chronic rhinosinusitis (CRS). The objective of this study was to examine microbiome changes in post-surgical CRS patients when rinsing with commercially available products containing xylitol or Lactococcus lactis. METHODS: A crossover-type protocol with a washout period was designed. Swab samples from anterior ethmoid cavities of CRS patients were collected prospectively at baseline. Subjects were provided packets containing either L. lactis W136 or xylitol in non-blinded fashion and instructed to add it to their rinse bottles daily for 28 days, after which another swab was taken. A saline wash-out period was completed and a third swab taken. A final 28-day regimen of the opposite product was followed by a final swab. DNA extraction and sequencing of the 16S rRNA gene allowed for global microbiome analysis. RESULTS: We enrolled 25 subjects with CRS and 10 controls resulting in 70 adequate samples. Increased detection of Lactococcus was observed after use of L. lactis. No significant trends in alpha or beta diversity as a result of treatment were observed. SNOT-22 score did not change significantly following treatment with xylitol, L. lactis, or saline. CONCLUSION: We did not detect any major clinical or microbiome-level effect due to treatment with two topical rinse products. Further research is needed to elucidate their clinical utility and possible probiotic effect. LEVEL OF EVIDENCE: 3.

The Cataract-linked Mutant Connexin50D47A Causes Endoplasmic Reticulum Stress in Mouse Lenses.

Mice expressing connexin50D47A (Cx50D47A) exhibit nuclear cataracts and impaired differentiation. Cx50D47A does not traffic properly, and homozygous mutant lenses show increased levels of the stress-responsive αB-crystallins. Therefore, we assessed whether expression of Cx50D47A led to endoplasmic reticulum (ER) stress in the lens in vivo Although pharmacologic induction of ER stress can be transduced by three different pathways, we found no evidence for activation of the IRE1α or ATF6 pathways in Cx50D47A-expressing lenses. In contrast, heterozygous and homozygous Cx50D47A lenses showed an increase in phosphorylated PERK immunoreactivity and in the ratio of phosphorylated to total EIF2α (2.4- and 3.3-fold, respectively) compared with wild type. Levels of ATF4 were similar in wild type and heterozygous lenses but elevated in homozygotes (391%). In both heterozygotes and homozygotes, levels of calreticulin protein were increased (184 and 262%, respectively), as was Chop mRNA (1.9- and 12.4-fold, respectively). CHOP protein was increased in homozygotes (384%). TUNEL staining was increased in Cx50D47A lenses, especially in homozygous mice. Levels of two factors that may be pro-survival, Irs2 and Trib3, were greatly increased in homozygous lenses. These results suggest that expression of Cx50D47A induces ER stress, triggering activation of the PERK-ATF4 pathway, which potentially contributes to the lens pathology and leads to increased expression of anti-apoptotic factors, allowing cell survival.

Comparative label-free LC-MS/MS analysis of colorectal adenocarcinoma and metastatic cells treated with 5-fluorouracil.

A label-free mass spectrometric strategy was used to examine the effect of 5-fluorouracil (5-FU) on the primary and metastatic colon carcinoma cell lines, SW480 and SW620, with and without treatment. 5-FU is the most common chemotherapeutic treatment for colon cancer. Pooled biological replicates were analyzed by nanoLC-MS/MS and protein quantification was determined via spectral counting. Phenotypic and proteomic changes were evident and often similar in both cell lines. The SW620 cells were more resistant to 5-FU treatment, with an IC(50) 2.7-fold higher than that for SW480. In addition, both cell lines showed pronounced abundance changes in pathways relating to antioxidative stress response and cell adhesion remodeling due to 5-FU treatment. For example, the detoxification enzyme NQO1 was increased with treatment in both cell lines, while disparate members of the peroxiredoxin family, PRDX2 or PRDX5 and PRDX6, were elevated with 5-FU exposure in either SW480 or SW620, respectively. Cell adhesion-associated proteins CTNNB1 and RhoA showed decreased expression with 5-FU treatment in both cell lines. The differential quantitative response in the proteomes of these patient-matched cell lines to drug treatment underscores the subtle molecular differences separating primary and metastatic cancer cells.

Dynamic changes appearing in collagen fibers during intrinsic tendon repair.

Intrinsic healing of severed tendons shows a delay in a gain in breaking strength and the tendon becomes translucent. The cause of tendon translucence was investigated in suture-repaired rat Achilles tendon. The repair site with adjacent translucent tendon were evaluated histologically on day 10 by immunofluorescence and transmission electron microscopy. The healing tendon translucent region by hematoxylin-eosin staining had few inflammatory cells, polarized light birefringence showed thinner collagen fibers, immunofluorescence showed few myofibroblasts, and transmission electron microscopy revealed frayed, irregular thin collagen fibers. During embryogenesis, tendon fibers grow by the addition of discreet collagen fibril segment structures. The speculation is that collagen fibril segment structures are released from collagen fibers within the translucent tendon region for reuse during the regeneration of tendon collagen fibers during intrinsic tendon repair. Healing tendon translucence is related to a decrease in the diameter of collagen fibers by the release of collagen fibril segments within tendon bundles/fascicles.