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In this article, I describe the lclogit2 command, an enhanced version of lclogit (Pacifico and Yoo, 2013, Stata Journal 13: 625–639). Like its predecessor, lclogit2 uses the expectation-maximization algorithm to fit latent class conditional logit (LCL) models. But it executes the expectation-maximization algorithm's core algebraic operations in Mata, so it runs considerably faster as a result. It also allows linear constraints on parameters to be imposed more conveniently and flexibly. It comes with the parallel command lclogitml2, a new stand-alone command that uses gradient-based algorithms to fit LCL models. Both lclogit2 and lclogitml2 are supported by a new postestimation command, lclogitwtp2, that evaluates willingness-to-pay measures implied by fitted LCL models. [ABSTRACT FROM AUTHOR]

Most Stata commands allow cluster( varname ) or vce(cluster clustvar ) as an option, popularizing the use of standard errors that are robust to oneway clustering. For adjusting standard errors for multiway clustering, there is no solution that is as widely applicable. While several community-contributed packages support multiway clustering, each package is compatible only with a subset of models that Stata's ever-expanding library of commands allows the researcher to fit. We introduce a command, vcemway, that provides a one-stop solution for multiway clustering. vcemway works with any estimation command that allows cluster( varname ) as an option, and it adjusts standard errors, individual significance statistics, and confidence intervals in output tables for multiway clustering in specified dimensions. The covariance matrix used in making this adjustment is stored in e(V), meaning that any subsequent call to postestimation commands that use e(V) as input (for example, test and margins) will also produce results that are robust to multiway clustering. [ABSTRACT FROM AUTHOR]

Detailed information about the excitatory and inhibitory synapses on the hypoglossal motoneurons may help understand the neural mechanism for control of the hypoglossal motoneuron excitability and hence the precise and coordinated movements of the tongue during chewing, swallowing and licking. For this, we investigated the distribution of GABA-, glycine (Gly)- and glutamate (Glut)-immunopositive (+) axon terminals on the genioglossal (GG) motoneurons by retrograde tracing, electron microscopic immunohistochemistry, and quantitative analysis. Small GG motoneurons (< 400 μm2 in cross-sectional area) had fewer primary dendrites, significantly higher nuclear/cytoplasmic ratio, and smaller membrane area covered by synaptic boutons than large GG motoneurons (> 400 μm2). The fraction of inhibitory boutons (GABA + only, Gly + only, and mixed GABA +/Gly + boutons) of all boutons was significantly higher for small GG motoneurons than for large ones, whereas the fraction of Glut + boutons was significantly higher for large GG motoneurons than for small ones. Almost all boutons (> 95%) on both small and large GG motoneurons were GABA + , Gly + or Glut +. The frequency of mixed GABA +/Gly + boutons was the highest among inhibitory boutons types for both small and large GG motoneurons. These findings may elucidate the anatomical substrate for precise regulation of the motoneuron firing required for the fine movements of the tongue, and also suggest that the excitability of small and large GG motoneurons may be regulated differently. [ABSTRACT FROM AUTHOR]

Objective To determine the diameter of the crown, total crown area, individual cusp area, and occlusal table area in Korean maxillary permanent molars, as well as dental characteristics relevant to the hypocone reduction trait. Materials and methods Subjects included 121 dental school students in Korea (81 men and 40 women). A digital image analysis system was used for measurements and we relied on visual scoring to assign categories of hypocone expression. Results The mean crown dimension was larger in the first molar (M1) than in the second molar (M2). Regarding differences according to gender, the crown diameter, total crown area, and individual cusp area were significantly larger in the men than in the women. The mean occlusal table area ratios were 61% for M1 and 57% for M2, and these ratios increased in proportion to the total crown area. With respect to the hypocone and other features of the maxillary molars, differences between the men and women were more prominent for M1 than for M2. The M2 hypocone tended to be smaller than the M1 hypocone, and hypocone reduction was inversely related to the cusp area of the protocone. The protocone area may be considered a reliable parameter for comparing race and/or gender differences in maxillary molars. Conclusion This study concerning characteristics of the maxillary molar occlusal surface in Koreans provides useful information for comparative studies among human races. [ABSTRACT FROM AUTHOR]

Amelogenin, an enamel matrix protein has been considered to be exclusively expressed by ameloblasts during odontogenesis. However, burgeoning evidence indicates that amelogenin is also expressed in non-mineralizing tissues. Under the hypothesis that amelogenin may be a functional molecule in developing hair follicles which share developmental features with odontogenesis, this study for the first time elucidated the presence and functional changes of amelogenin and its receptors during rat hair follicle development. Amelogenin was specifically localized in the outer epithelial root sheath of hair follicles. Its expression appeared in the deeper portion of hair follicles, i.e. the bulbar and suprabulbar regions rather than the superficial region. Lamp-1, an amelogenin receptor, was localized in either follicular cells or outer epithelial sheath cells, reflecting functional changes during development. The expression of amelogenin splicing variants increased in a time-dependent manner during postnatal development of hair follicles. Amelogenin expression was increased by treatment with cyclosporin A, which is an inducer of anagen in the hair follicle, whereas the level of Lamp-1 and -2 was decreased by cyclosporin A treatment. These results suggest that amelogenin may be a functional molecule involved in the development of the hair follicle rather than an inert hair shaft matrix protein. [ABSTRACT FROM AUTHOR]

Highlights: [•] We compare preferences on nursing jobs elicited by profile and multi-profile case DCEs. [•] The paper is the first to contrast the two types of DCEs using monetary and nonmonetary attributes. [•] Preferences are comparable across the DCEs but only for non-monetary attributes. [•] Respondents value salary gains relatively more in the multi-profile DCEs. [•] The evidence suggests that this discrepancy is not due to the variation in cognitive difficulty. [ABSTRACT FROM AUTHOR]

Although the level of neuroscience research is rapidly developing with the introduction of new technologies, the method of neuroanatomy education remains at the traditional level and requires improvement to meet the needs of educators and trainees. We developed a new three‐dimensional (3D) printed device (human brain‐cutting mold, HBCM) for creating human brain slices; moreover, we demonstrated a simple method for creating semi‐permanent ultraviolet (UV) resin‐mounted brain slice specimens for neuroanatomy education. We obtained brain slices of uniform thickness (3 mm) through the HBCM; the resultant brain slices were optimal for assessing morphological details of the human brain. Furthermore, we used an agar‐embedding method for brain‐slicing with the HBCM, which minimized geometrical distortions of the brain slices. Also, we prepared semi‐permanent brain serial specimens using an acrylic brain slice frame and UV‐curable resin, which was highly compatible with moist bio‐specimens. During UV resin curing, neither air bubble formation nor color change occurred. The resultant UV resin‐mounted brain slices produced definite coronal sections with high transparency and morphological accuracy. We also performed 3D modeling by stacking brain slice images that differentiated the cortical area and nine subcortical regions via manual segmentation. This method could be a reliable alternative for displaying high‐quality human brain slices and would be helpful for students and trainee to understand anatomical orientation from 2D images to 3D structures. Also, this may present an innovative approach for preparing and preserving coronal sections of the normal or pathological human brain. [ABSTRACT FROM AUTHOR]

Aim: We aimed to identify a key molecule that maintains periodontal tissue homeostasis during biophysical force‐induced tooth movement (BTM) by orchestrating alveolar bone (AB) remodelling. Materials and Methods: Differential display‐PCR was performed to identify key molecules for BTM in rats. To investigate the localization and expression of the identified molecules, immunofluorescence, real‐time RT‐PCR and Western blotting were performed in rats and human periodontal ligament (PDL) cells. Functional test and micro‐CT analysis were performed to examine the in vivo effects of the identified molecules on BTM. Results: Secretory leucocyte peptidase inhibitor (SLPI) in the PDL was revealed as a key molecule for BTM‐induced AB remodelling. SLPI was enhanced in the PDL under both compression and tension, and downregulated by an adenyl cyclases inhibitor. SLPI induced osteoblastogenic genes including runt‐related transcription factor 2 (Runx2) and synergistically augmented tension‐induced Runx2 expression. SLPI augmented mineralization in PDL cells. SLPI induced osteoclastogenic genes including receptor activator of nuclear factor kappa‐Β ligand (RANKL) and synergistically augmented the compression‐induced RANKL and macrophage colony‐stimulating factor (MCSF) expression. Finally, the in vivo SLPI application into the AB significantly augmented BTM. Conclusions: SLPI or its inhibitors might serve as a biological target molecule for therapeutic interventions to modulate BTM. [ABSTRACT FROM AUTHOR]

Neuregulin 1 (NRG1) exhibits potent neuroprotective properties. The aim of the present study was to investigate the antioxidative effects and underlying mechanisms of NRG1 against H2O2-induced oxidative stress in primary rat cortical neurons. The expression level of the excitatory amino acid carrier 1 (EAAC1) protein was measured by Western blotting and immunocytochemistry. The levels of lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) generation, superoxide dismutase (SOD) activity, GPx activity, and mitochondrial membrane potential (∆ψm) were determined to examine cell death and the antioxidant properties of NRG1 in primary rat cortical neurons. H2O2 reduced the expression of EAAC1 in a dose-dependent manner. We found that pretreatment with NRG1 attenuated the H2O2-induced reduction in EAAC1 expression. Moreover, NRG1 reduced the cell death and oxidative stress induced by H2O2. In addition, NRG1 attenuated H2O2-induced reductions in antioxidant enzyme activity and ∆ψm. Our data indicate a role for NRG1 in protecting against oxidative stress via the regulation of EAAC1. These observations may provide novel insights into the mechanisms of NRG1 activity during oxidative stress and may reveal new therapeutic targets for regulating the oxidative stress associated with various neurological diseases. [ABSTRACT FROM AUTHOR]

The formation of dentin and enamel is initiated by the differentiation of odontogenic precursor cells into odontoblasts and ameloblasts, respectively. This study was performed to identify new molecules involved in the differentiation of odontogenic cells. The genes expressed differentially between the root stage (after the differentiation of odontogenic cells and dental hard-tissue formation) and the cap stage (before the differentiation of odontogenic cells and dental hard-tissue formation) were searched using differential display PCR. For the first time, synaptic vesicle protein ( SV) 2b, an important transmembrane transporter of Ca2+-stimulated vesicle exocytosis, was identified as a differentially expressed molecule. Real-time PCR and western blotting revealed an increase in the transcriptional and translational levels of SV2b during or after the differentiation of odontogenic cells. Immunofluorescence revealed this molecule to be localized in not only fully differentiated odontoblasts but also in pre-odontoblasts before dentin matrix secretion. The expression pattern of the SV2a isoform was similar to that of the SV2b isoform, whereas the SV2c isoform showed a contrasting pattern of expression. After treatment with alendronate, an inhibitor of protein isoprenylation for the transport of secretory vesicles, the expression of SV2a and SV2b decreased, whereas that of SV2c increased. These results suggest that the SV2 isoforms are functional molecules of (pre)odontoblasts which may be involved in vesicle transport. [ABSTRACT FROM AUTHOR]

Yang S-Y, Ko H-M, Kang J-H, Moon Y-H, Yoo H-I, Jung N-R, Kim M-S, Cho J-H, Oh W-M, Kim S-H. Relaxin is up-regulated in the rat ovary by orthodontic tooth movement. Eur J Oral Sci 2011; 119: 115-120. © 2011 Eur J Oral Sci Relaxin (Rln) is an ovarian hormone that stimulates osteoclastic and osteoblastic activities and connective tissue turnover. To investigate the expression of Rln during orthodontic tooth movement, rats were implanted with orthodontic appliances that connected a spring from the upper incisors to the first molar with a 70 cN force. Rats in each group were killed 6, 48, and 144 h after activating the appliance, and the levels of Rln1 and Rln3 expression in the ovary were determined by real-time RT-PCR, northern blots, western blots, and immunofluorescence analyses. The amount of tooth movement induced by the orthodontic force increased in a time-dependent manner. The levels of Rln1 mRNA increased by 12-, 41-, and 263-fold at 6, 48, and 144 h, respectively, after orthodontic tooth movement. The time-dependent increase in the concentration of Rln 1 protein in the ovary was also confirmed by western blotting. Rln 1 was localized in the granulosa cells of the ovarian follicles, and the immunoreactivity against Rln 1 was increased by the movement. In contrast, the concentration of Rln 3 was below the level of detection. The results of this study suggest that local changes in periodontal tissues induced by orthodontic tooth movement may affect Rln1 expression in the ovary. However, further studies are needed to decipher the mechanisms involved and the possible contribution of the increased level of expression of Rln 1 to the tooth movement. [ABSTRACT FROM AUTHOR]