Comparison between two-dimensional and midsagittal three-dimensional cephalometric measurements of dry human skulls

The aim of this study was to compare two- and three-dimensional cephalometric values by using a three-dimensional analysis based on the midsagittal plane. Spherical metal markers were fixed on to the anatomical landmarks of 10 human skulls, which were examined radiographically with conventional lateral cephalograms and cone-beam computed tomographic (CBCT) scans. Preprogrammed analyses calculated the 18 angular and linear two- and three-dimensional cephalometric values. An error study was made to assess the accuracy and reliability of the methods used. Both sets of values were compared using Wilcoxon's signed-rank test. Probabilities of less than 0.05 were accepted as significant. Reliability of the measurements was assessed by intraclass correlation coefficients (ICC) based on absolute agreement. The method error (ME) was tiny (mean ME < 0.61 measuring unit) and reliable (ICC > 0.97). Comparison of the two- and three-dimensional measurements showed that that they were reliable (ICC > 0.88) and that there were no significant differences (P = 0.41-1.00). The values from the cephalometric analyses were comparable and interchangeable when using the midsagittal three-dimensional approach as described.     

Novel Stability-Indicating RP-HPLC Method for the Simultaneous Estimation of Clindamycin Phosphate and Adapalene along with Preservatives in Topical Gel Formulations

A novel stability-indicating RP-HPLC method was developed for the simultaneous estimation of clindamycin phosphate (hydrophilic), adapalene (hydro-phobic), phenoxyethanol, and methylparaben in topical gel formulations. Optimum chromatographic separation among the analytes and stress-induced degradants peaks was achieved on the XBridge C18 (50 × 4.6 mm, 3.5 µm) column using a mobile phase consisting of a variable mixture of pH 2.50 ammonium hydrogen phosphate buffer, acetonitrile, and tetrahydrofuran with gradient elution. Detection was performed at 210 nm for phenoxyethanol, methylparaben, and clindamycin phosphate and 321 nm for adapalene. The method was optimized with a unique diluent selection for the extraction of clindamycin phosphate and adapalene from the gel matrix. The developed method was validated for method precision, specificity, LOD and LOQ, linearity, accuracy, robustness, and solution stability as per ICH guidelines. The proposed method can be employed for the quantification of clindamycin phosphate, adapalene, phenoxyethanol, and methylparaben in commercial topical gel formulations.     

Travel Distance and Home Dialysis Rates in the United States

♦ Introduction: Rural residence is associated with increased peritoneal dialysis (PD) utilization. The influence of travel distance on rates of home dialysis utilization has not been examined in the United States. The purpose of this study was to determine whether travel distances to the closest home and in-center hemodialysis (IHD) facilities are a barrier to home dialysis.♦ Methods: This was a retrospective cohort study of patients aged ≥ 18 years initiating dialysis between 2005 and 2011. Unadjusted PD and home hemodialysis (HHD) rates were compared by travel distances to both the closest home dialysis and closest IHD facilities. Adjusted PD and HHD utilization rates were examined using multivariable logistic regression models.♦ Results: There were 98,608 patients in the adjusted analyses. 55.5% of the dialysis facilities offered home dialysis. IHD, PD and HHD patients traveled median distances of 5.4, 3.5 and 6.6 miles respectively to their initial dialysis facilities. Unadjusted analyses showed an increase in PD rates and decrease in HHD rates with increased travel distances. Adjusted odds of PD and HHD were 1.6 and 1.2 respectively for a ten mile increase in distance to the closest home dialysis facility, while for distances to the closest IHD facility the odds ratios for both PD and HHD were 0.7 (all p < 0.01).♦ Conclusions: In metropolitan areas, PD and HHD generally increased with increased travel distance to the closest home dialysis facility and decreased with greater distance to an IHD facility. Examination of travel distances to PD and HHD facilities separately may provide further insight on specific barriers to these modalities which can serve as targets for future studies examining expansion of home dialysis utilization.     

Folate deficiency is associated with the formation of complex nuclear anomalies in the cytokinesis‐block micronucleus cytome assay

Chromosomal instability (CIN) is an important hallmark to oncogenesis and can be diagnosed morphologically by the presence of nuclear anomalies such as micronuclei (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBuds). We have identified additional nuclear anomalies formed under folate‐deficient conditions, defined as “fused” nuclei (FUS), “circular” nuclei (CIR), and “horse‐shoe” nuclei (HS) and investigated their suitability for inclusion as additional CIN biomarkers in the lymphocyte cytokinesis‐block micronucleus cytome (CBMN‐Cyt) assay. Although the morphological appearance of FUS, CIR, and HS suggested an origin from multiple NPB in the fusion region between the two nuclei, the very low frequency of dicentric chromosomes in metaphase spreads from these cultures did not support this model. Fluorescence in situ hybridization (FISH) analysis of cytokinesis‐blocked binucleated (BN) cells with peptide nucleic acid probes for telomeres and centromeres (PNA–FISH) revealed a high proportion of fusion regions contained both centromeric and telomeric DNA. This suggests that folate deficiency may disrupt the process of sister chromatid separation and chromosome segregation during mitosis. It was concluded that the FUS, CIR, and HS morphologies represent promising biomarkers of CIN that are sensitive to folate deficiency, and further validation and investigation of the mechanisms responsible for their formation is warranted. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.