Subjective and Objective Measures of Dryness Symptoms in Primary Sjögren's Syndrome: Capturing the Discrepancy.

OBJECTIVE: To develop a novel method for capturing the discrepancy between objective tests and subjective dryness symptoms (a sensitivity scale) and to explore predictors of dryness sensitivity. METHODS: Archive data from the UK Primary Sjögren's Syndrome Registry (n = 688) were used. Patients were classified on a scale from -5 (stoical) to +5 (sensitive) depending on the degree of discrepancy between their objective and subjective symptoms classes. Sensitivity scores were correlated with demographic variables, disease-related factors, and symptoms of pain, fatigue, anxiety, and depression. RESULTS: Patients were on average relatively stoical for both types of dryness symptoms (mean ± SD ocular dryness -0.42 ± 2.2 and -1.24 ± 1.6 oral dryness). Twenty-seven percent of patients were classified as sensitive to ocular dryness and 9% to oral dryness. Hierarchical regression analyses identified the strongest predictor of ocular dryness sensitivity to be self-reported pain and that of oral dryness sensitivity to be self-reported fatigue. CONCLUSION: Ocular and oral dryness sensitivity can be classified on a continuous scale. The 2 symptom types are predicted by different variables. A large number of factors remain to be explored that may impact symptom sensitivity in primary Sjögren's syndrome, and the proposed method could be used to identify relatively sensitive and stoical patients for future studies.

Full life-cycle assessment of gene flow consistent with fitness differences in transgenic and wild-type Japanese medaka fish (Oryzias latipes).

Transgenic fish in development for aquaculture could escape from farms and interbreed with wild relatives in the nearby environment. Predicting whether escapes would result in transgene introgression is a major challenge in assessing environmental risks of transgenic fish. Previous studies have simulated gene flow from transgenic fish using mathematical modeling of fitness traits to predict the relative selective value of transgenic genotypes. Here, we present the first study of gene flow over the full life cycle in openly-breeding populations of transgenic animals, along with measurement of fitness traits. We conducted two invasion experiments in which we released two lines of growth-enhanced transgenic fish (T67 and T400), Japanese medaka (Oryzias latipes), into populations of wild-type (W) medaka in structured mesocosms. After several generations, the frequency of transgenic fish varied across replicates in the first invasion experiment (6 months), but the frequency of transgenic fish decreased in the second experiment (19 months). We also measured selected fitness traits in transgenic and wild-type medaka because these traits could be used to predict the relative selective value of a genotype. We found that: T400 males were more fertile than W males; offspring of W females lived longer than those with transgenic mothers; and W and T67 females reached sexual maturity sooner than T400 females. In contrast with other research that reported larger transgenic males had a mating advantage, we found that W males obtained more matings with females than T males; genetic background effects may account for our differing results as we compared W and T fish derived from different strains. The decreasing frequency of transgenic fish in the second invasion experiment suggests that transgenic fish had a selective disadvantage in the experimental environment. Our finding of transgenic advantage of some fitness traits and wild-type advantage in others is consistent with our invasion experiment results.

Silver nano-inukshuks on germanium.

The integration of metallic nanostructures with semiconductors is important for a variety of technological applications. Through an efficient galvanic displacement reaction on germanium, complex silver nanostructures form spontaneously in aqueous conditions at room temperature. The structures, termed nano-inukshuks, are based on stacks of hexagonal metallic structures that grow, initially, parallel to the surface normal of the germanium. TEM, SEM, XPS, XRD, and EDS indicate that the structures are crystalline silver and, based on open cell potential studies, that their nucleation takes place in the first 100 s, followed by growth of the silver structures, most likely through Volmer-Weber growth.