Reproducibility and Validity of a Semi-quantitative Food Frequency Questionnaire in Men Assessed by Multiple Methods

Among 626 participants of the Men’s Lifestyle Validation Study (2011-2013), we evaluated the validity and reproducibility of a self-administered 152-item semiquantitative food frequency questionnaire (SFFQ) using two 7-day dietary records (7DDRs), four automated self-administered 24-hour dietary recalls (ASA24s), four 24-hour urine samples, one doubly-labeled water measurement (repeated in 104 participants), and two fasting blood samples, collected over 15 months. Compared to 7DDRs, SFFQs underestimated energy intake, macronutrients, and sodium intake, but overestimated some micronutrients. The mean of Spearman correlation coefficients was 0.66 (range 0.38 to 0.88) between 46 energy-adjusted nutrients estimated from 7DDRs and the final SFFQ, de-attenuated for within-person variation in the 7DDRs. These deattenuated correlations were similar using ASA24s as the comparison. Relative to biomarkers, SFFQs underestimated energy, sodium, and protein intakes, and the sodium:potassium ratio. The energy-adjusted correlations between the final SFFQ and the biomarkers were slightly lower than the correlations between the SFFQ and 7DDRs. Using method of triads to calculate validity coefficients (VC), the median VC between SFFQ and true intake was 0.65 and 0.69 using 7DDRs or ASA24s as the third method. These data indicate that this SFFQ provided reasonably valid estimates for a wide range of nutrients when evaluated by multiple comparison methods.

Color Shift, Color Stability, and Post-Polishing Surface Roughness of Esthetic Resin Composites

The aim of this study was to compare color shift, color stability, and post-polishing surface roughness of esthetic restorative materials. Twenty-five disc-shaped specimens (10 mm in diameter and 2 mm in thickness) from five esthetic resin materials (Z250XT, IPS Empress-Direct, G-ænial, Vit-l-escence, and Ceram.X) were fabricated. Color shift before and immediately after light-curing (∆E0) then color stability after immersion in tea, coffee, berry juice, and distilled water were measured using a spectrophotometer. Color changes were measured after 2 (ΔE2), 4 (ΔE4), 6 (ΔE6), and 8 weeks (ΔE8). Surface roughness values (Rq) were determined using an optical profilometer after polishing using a rotary polishing system. Data were analyzed using ANOVA and multiple comparison methods at 0.05 significance level. There were no significant differences between the tested materials regarding color shift except between Vit-l-escence and Ceram.X (p = 0.033). There was no significant difference between coffee and tea solutions (p = 1.0) and between berry juice and distilled water (p = 0.15). There was no difference between the tested materials regarding Rq (p = 0.057). Ceram.X was associated with the lowest ΔE8 values overall. Tested materials were comparable regarding color shift and post-polishing surface roughness. Susceptibility to staining was dependent on the material.

Spatial Difference of Transit-Based Accessibility to Hospitals by Regions Using Spatially Adjusted ANOVA

This paper proposes a spatial difference analysis method for evaluating transit-based accessibility to hospitals using spatially adjusted ANOVA. This method specializes in examining spatial variations of accessibility to hospitals by regions (i.e. administrative districts or subdistricts). The spatial lag model is applied to adjust traditional ANOVA, which reduces spatial dependency and avoids false rejection to null hypothesis. Multiple comparison methods are used for further detection of differences in accessibility between regions. After multiple comparison, accessibility within regions is classified into three levels. The study is conducted on two scales—administrative districts and subdistricts—to discuss spatial variations in macro and micro dimensions respectively in the central part of Wuhan, China. Accessibility is calculated by using a simple model and a gravity model. The final classification results showed that the spatially adjusted method is more reliable than the traditional non spatially adjusted one and the gravity model can better detect more hidden information about the inequal distribution of medical resources. It is also found that the subdistricts, which have significantly lower accessibility to hospitals than others, are mainly distributed in Hongshan and Qingshan district. Our study hopes to shed new lights in spatial difference analysis for accessibility and provide policy recommendations that would promote equality in provisions of public health services.

A Mixed Effect Emax Model Applied for Determination of Malathion Optimal Dose

Background: Malathion is an organophosphate insecticide and is the most appropriate one used widely in the world. Organophosphate insecticides cause a specific biochemical defect in the body. A major cause of this wastage is inhibition of cholinesterase (ChE) enzyme. Objectives: This study was conducted to determine the optimal dose of the pesticide malathion which inhibited 50% of ChE enzyme. Materials and Methods: An experimental study was conducted on 18 male rats weighing 180-250 g. The rats were randomly divided into 6 groups. The Ellman method was used to measure the acetylcholinesterase (AChE) enzymatic activity. Doses 0, 25, 50, 100, 200 and 400 mg/kg of pesticide malathion was tested on rats to determine the dose of the pesticide malathion with 50% inhibition of the ChE enzyme, at 24, 48, and 72 hours. According to these data, Emax model was fitted, then the median effective doses of the pesticide malathion were estimated at different time intervals, separately. Results: Based on the reduction Emax model, the optimal dose 29.14 mg/kg was determined at 72 time point. Conclusion: Using the mixed effect Emax model instead of the multiple comparison methods, such analysis of variance was suggested to determine the optimal dose of organophosphates such as malathion, which provide more accurate results.

311 TEMPERATURE DURING OVERNIGHT HOLDING IN MEIOSIS INHIBITOR-FREE MEDIUM AFFECTS CHROMATIN CONFIGURATION AND MEIOTIC RESUMPTION IN EQUINE OOCYTES

Immature equine oocytes may be held overnight in an Earle's/Hanks' M199-based medium in the absence of meiotic inhibitors (EH medium) to schedule the onset of in vitro maturation. Holding in EH has been shown not to affect meiotic or developmental competence of equine oocytes (Choi et al. 2006 Theriogenology 66, 955–963). However, no studies have been performed to identify the mode by which this medium suppresses meiosis. We hypothesised that holding temperature may affect oocyte meiotic arrest. The effect of 3 holding temperatures (25, 30, 38°C) on chromatin status was investigated after Hoechst 33258 staining (Hinrichs et al. 2005 Biol. Reprod. 72, 1142–1150). Oocytes were recovered by scraping of follicles from slaughterhouse-derived ovaries. Data were analysed by Chi-squared test and one-way ANOVA followed by Dunn's or Holm-Sidak Multiple Comparison methods. A level of P < 0.05 was considered significant. There were no significant differences in chromatin configuration between oocytes held overnight at 25°C (25°C-held) and controls (immediately-fixed oocytes); the proportion of oocytes showing meiotic resumption was 1/27, 4% and 0/26, 0%, respectively (not significant, NS). In contrast, holding at higher temperature significantly increased meiosis resumption (14/38, 37% and 14/28, 50%, at 30 and 38°C, respectively; P < 0.01) and reduced the proportion of oocytes showing the most meiotically-competent germinal-vesicle (GV) configuration (condensed chromatin, CC; 24 to 29% v. 65 to 70% for control and 25°C-held, respectively; P < 0.05). Based on these results, a subsequent experiment was performed in which oocyte meiotic stage and mitochondrial (mt) potential of 25°C-held (n = 29) and control (n = 36) oocytes was evaluated. Nuclear chromatin, mt activity (MitoTracker orange), intracellular reactive oxygen species (ROS) levels (2′,7′-dichlorodihydrofluorescein diacetate, DCDHFDA), and mt/ROS colocalization (Pearson's coefficient) were analysed by epifluoscence and confocal microscopy (Martino et al. 2012 Fertil. Steril. 97, 720–728). Meiotic arrest after EH treatment at 25°C was confirmed (0/29, 0% v. 5/36, 14% for meiotic resumption in 25°C-held and controls, respectively; NS). At any GV stage, 25°C-held treatment had no effect on mt activity, ROS levels, or mt/ROS colocalization. For example, in CC oocytes, values for control and 25°C-held, respectively, were: MitoTracker, 547.8 ± 499.5 v. 722.9 ± 390.3; DCF fluorescence intensity, 278.5 ± 179.3 v. 378 ± 185, and mt/ROS colocalization, 0.5 ± 0.1 v. 0.5 ± 0.2; these were not significantly different (NS). In conclusion, EH holding at 25°C maintains meiotic arrest, viability, and mt potential of equine oocytes.

Statistical Methods for Identifying Conserved Residues in Multiple Sequence Alignment

The assessment of residue conservation in a multiple sequence alignment is a central issue in bioinformatics. Conserved residues and regions are used to determine structural and functional motifs or evolutionary relationships between the sequences of a multiple sequence alignment. For this reason, residue conservation is a valuable measure for database and motif search or for estimating the quality of alignments. In this paper, we present statistical methods for identifying conserved residues in multiple sequence alignments. While most earlier studies examine the positional conservation of the alignment, we focus on the detection of individual conserved residues at a position. The major advantages of multiple comparison methods originate from their ability to select conserved residues simultaneously and to consider the variability of the residue estimates. Large-scale simulations were used for the comparative analysis of the methods. Practical performance was studied by comparing the structurally and functionally important residues of Src homology 2 (SH2) domains to the assignments of the conservation indices. The applicability of the indices was also compared in three additional protein families comprising different degrees of entropy and variability in alignment positions. The results indicate that statistical multiple comparison methods are sensitive and reliable in identifying conserved residues.