Molecular Evolution and Diversification of Proteins Involved in miRNA Maturation Pathway.

Small RNAs (smRNA, 19-25 nucleotides long), which are transcribed by RNA polymerase II, regulate the expression of genes involved in a multitude of processes in eukaryotes. miRNA biogenesis and the proteins involved in the biogenesis pathway differ across plant and animal lineages. The major proteins constituting the biogenesis pathway, namely, the Dicers (DCL/DCR) and Argonautes (AGOs), have been extensively studied. However, the accessory proteins (DAWDLE (DDL), SERRATE (SE), and TOUGH (TGH)) of the pathway that differs across the two lineages remain largely uncharacterized. We present the first detailed report on the molecular evolution and divergence of these proteins across eukaryotes. Although DDL is present in eukaryotes and prokaryotes, SE and TGH appear to be specific to eukaryotes. The addition/deletion of specific domains and/or domain-specific sequence divergence in the three proteins points to the observed functional divergence of these proteins across the two lineages, which correlates with the differences in miRNA length across the two lineages. Our data enhance the current understanding of the structure-function relationship of these proteins and reveals previous unexplored crucial residues in the three proteins that can be used as a basis for further functional characterization. The data presented here on the number of miRNAs in crown eukaryotic lineages are consistent with the notion of the expansion of the number of miRNA-coding genes in animal and plant lineages correlating with organismal complexity. Whether this difference in functionally correlates with the diversification (or presence/absence) of the three proteins studied here or the miRNA signaling in the plant and animal lineages is unclear. Based on our results of the three proteins studied here and previously available data concerning the evolution of miRNA genes in the plant and animal lineages, we believe that miRNAs probably evolved once in the ancestor to crown eukaryotes and have diversified independently in the eukaryotes.

Sensory ataxia rating scale: Development and validation of a functional scale for patients with sensory neuronopathies.

Sensory neuronopathies (SN) result from dorsal root ganglia damage and manifest with a combination of sensory deficits and proprioceptive ataxia. Characterization of the natural history and development of therapeutic trials are hampered by the lack of clinical scales that capture the whole spectrum of SN-related manifestations. We propose and validate a rating instrument for SN. Three experienced neuromuscular specialists developed items to rate SN. The resultant instrument was later validated by the assessment of the intra-class correlation coefficient, for inter-rater validity in 48 SN patients, and later in a smaller subset of 16 patients to assess its intra-rater validity. Standardized Crombach's alpha and Oblimin rotation analysis were performed to verify internal consistency and items' relationship, respectively. Evaluation of Sensory Ataxia Rating Scale (SEARS)'s external validity was performed by comparison to: scale for the assessment and rating of ataxia (SARA), Beck balance scale (BBS), and INCAT sensory sum score (ISS). A 10-item scale with an intra-class correlation coefficient >0.95 for intra- and inter-rating measurements with a good internal consistency (standardized Cronbach's alpha of 0.83) were observed. There was a normal distribution of the scores without a floor or ceiling effect. A moderate to good correlation between SEARS and SARA, BBS, and ISS was observed. SEARS is a reliable, easy-to-perform and consistent instrument to rate SN. Larger cohorts and multicenter studies are needed to validate its usefulness towards possible treatment trials.

The Development of Nonanatomic Denture Occlusion - Part I.

Part I of this two-part article concentrates on the early 20th century origin of the nonanatomic concept of complete denture occlusion. It focuses on Dr. Victor Sears, who in 1922 made a courageous departure from convention when he introduced the design for his "Chewing Members." Development of these teeth marked the birth of the School of Nonanatomic Denture Occlusion. Dr. Sears' 35-year journey of research and development is traced here through his mid-1950s association with Dr. Simon Myerson. Their Myerson-Sears design set the standard for flat-planed, nonanatomic denture teeth for the next half century.

Clinical efficacy of fractional laser (AffirmTM) with combined apex pulse and multiplex technology on post-acne scars and other skin lesions / 中华医学美学美容杂志

Objective To evaluate the clinical efficacy of factional multiplex laser (AffirmTM) with combined apex pulse (CAP) technology in treating depressive acne scars,post inflammatory erythema and enlarged pores and other lesions.By following up,the correlative factors were analyzed to guide the further use of the factional laser (AffirmTM) with CAP technology.Methods Patients who received the AffirmTM laser therapy from Sept.2007 to July 2008 were enrolled in this retrospective follow-up study.Pictures were taken before and after each treatment during the therapy.Then the pictures were evaluated by dermatologists to attain object variables.Other subject variables from patients were recorded during survey.The relation between the efficacy and age,sex and treatment frequencies were analyzed statistically.Results The effective rate was 25.34 ％ for post-acne scars,36.84 ％ for post-acne erythema.28.57 ％ for enlarged pores,and 14.29 ％ for rythids.Nonparametric test showed no statistical difference with gender or age.There was correlation between efficacy and treatment frequencies.No severe adverse effect was observed.Conclusions AffirmTM laser with CAP technology has a good effect on treating post-acne depressed scars and erythema,enlarged pores and fine rythids.