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In the mammalian central nervous system, a remarkably small number of connexins is used in electrical synapses, with the majority formed from Cx36. A larger number has been detected in teleosts, with some seeming to serve restricted roles. Here, we report the discovery of a new connexin expressed in the zebrafish lens and a limited set of neurons. Zebrafish cx79.8 (gja8a), previously annotated incorrectly as cx50.5 based on a partial cDNA sequence, is a homologue of mammalian Cx50 (Gja8). We examined its expression through transgenic promoter-reporter constructs, in situ hybridization, and immunolabeling, and examined regulation of coupling in transfected HeLa cells. cx79.8 was expressed most strongly in the lens, but expression was also found in several groups of neurons in the cerebellum and related areas at the midbrain-hindbrain boundary, in cone photoreceptors, and in neurons in the retinal inner nuclear and ganglion cell layers. Labeling in the retina with antibodies against two C-terminal epitopes revealed numerous small punctate spots in the inner plexiform layer and along the somata of cones. Abundant gap junctions were labeled in the outer 1/3 of the lens, but were absent from the center, suggesting that the epitopes or the entire protein was absent from the center. Cx79.8 tracer coupling was strongly regulated by phosphorylation, and was extremely low in control conditions in HeLa cells due to protein phosphatase 2A activity. These properties allow coupling to be strongly restricted in situ, a frequently observed property for electrical synapses. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 548-561, 2017.

The cadaver dissection course remains a time-honored tradition in medical education, partly because of its importance in cultivating professional attitudes in students. This study aims to investigate students' attitudes-specifically characterized as "detached concern"-in a cadaver dissection course. An interpretative phenomenological analysis was performed with semi-structured, focus group interviews among 12 third-year medical students from a Taiwanese medical school to reveal their perceptions and learning experiences regarding human cadaver dissection. Based on these interviews, four relevant categories of perspectives were delineated: (1) initial emotional impact, (2) human referents, (3) coping strategies, and (4) ways of perceiving cadavers. Students were divided into two groups based on these categories. Students in Group 1 developed mechanisms described as "detachment" to cope with their initial emotional reactions to cadaveric dissection, which was noted to have disruptive effects on their learning. They considered human referents to be learning obstacles and avoided contact with or thinking about the human referents while performing dissections. Some of them faced a conflict between perceiving the cadaver as a learning tool versus as a human being. This impasse could be resolved if they latently adopted a "perspective switch" between the concept of a learning tool (rational aspect) and a human being (sensitive aspect). The students in Group 2 had no obvious initial emotional reaction. For them, the human referents functioned as learning supports, and the cadavers were consistently perceived as humans. These students held the notion that "cadaver dissection is an act of love"; therefore, they did not experience any need to detach themselves from their feelings during dissection. This alternative attitude revealed that detached concern alone is not sufficient to describe the entire range of medical students' attitudes toward cadaver dissection. Anat Sci Educ 9: 265-271. © 2015 American Association of Anatomists.

We used pseudo-triple-stage tandem MS to rapidly differentiate terminal α(2,3)- and α(2,6)-linked sialic acids of glycopeptides and native glycans. The precursor ions generate important diagnostic fragments to distinguish different terminal linked isomeric glycans and glycopeptides based on collision-induced dissociation (CID). The diagnostic ions include hexose linked with N-acetylhexosamine residues, sialic acid with the loss of water, and sialic acid residues. Their values of mass-to-charge ratio (m/z) are at 366.14, 274.09, and 292.10, respectively. The relative intensity ratios (RIR) were calculated by the intensity of signals at m/z 274.09 and 292.10 divided by the intensity of the signal at m/z 366.14. Under optimal conditions of an in-source fragmentation voltage of 70 V and a normalized collision energy of 30 %, the difference in RIR of diagnostic ions between terminal α(2,3)-linked sialic acid of glycopeptide (1.3) and terminal α(2,6)-linked sialic acid of glycopeptide (

We previously demonstrated that when arsenic trioxide (ATO)-induced mitotically arrested HeLa S3 cells (AIMACs) were treated with staurosporine (SSP) the cells rapidly exited mitosis. To better define the cellular targets and the underlying mechanisms of AIMACs, we applied 2-D DIGE followed by LC-MS/MS analysis and showed that SSP induced a significant change in the phosphoproteome of AIMACs. Among the proteins whose phosphorylation was modulated by SSP, we identified Hsp70, Rad 23B, and eukaryotic translation initiation factor 4B as potentially new substrates of polo-like kinase 1 (Plk1), an essential serine/threonine kinase with versatile mitotic functions. Since Hsp70 is a stress protein responsible for ATO treatment, we further identified Thr(13) , Ser(362) , Ser(631) , and Ser(633) on Hsp70 intracellularly phosphorylated in AIMACs by combining TiO(2) phospho-peptides enrichment and MS/MS analysis. Using antibody specifically against phosph-Ser(631) Hsp70 and further aided by expression of kinase-dead Plk1 and pharmacological inhibition of Plk1, we concluded that Ser(631) on Hsp70 is phosphorylated by Plk1 in AIMACs. By immnuofluorescent staining, we found the colocalization of Hsp70 and Plk1 in AIMACs but not in interphase cells. In addition, Plk1-mediated phosphorylation of Hsp70 prevented AIMACs from mitotic death. Our results reveal that Hsp70 is a novel substrate of Plk1 and that its phosphorylation contributes to attenuation of ATO-induced mitotic abnormalities.

Aims and Objectives. The aim of this study was to understand the factors related to intention to leave their job among intensive care unit (ICU) nurses in eastern Taiwan and to make between-group comparisons between an intention to leave and an intention to stay as well as to predict the influencing factors that affect ICU staff nurses’ intention to leave. Background. Nurses’ intention to leave their job may have an important impact on the actual turnover of nurses. The issue has always been of concern to nursing executives. Only limited empirical studies in the area have been investigated in an Asian culture context and particularly the eastern Taiwan region. Methods. A cross-sectional predictive study was performed during 2005 with 130 nurses recruited from two ICUs at a medical centre. A researcher-designed questionnaire based on the Cooper's model with structured interviews was used to determine each nurse's characteristics and their intention to leave their job. Multiple logistic regression analysis was employed to investigate the various factors associated with this. Results. The overall response rate was 100%; 63 (48·9%) revealed that they intended to leave their jobs. The findings were that their self-rated health status, the number of diseases, the level of happiness, the presence of depression, job satisfaction, sleep quality, type of license and their unit were significantly associated with an intention to leave (p = 0·05–0·001). Depression and sleep quality proved to be the most significant predictors of ICU staff nurses’ intention to leave their job. Conclusions. The findings suggest that there is a need to take steps to improve nurses’ health-related quality of life and to develop effective strategies to improve nurse retention. Relevance to clinical practice. A succinct validated instrument would help identify the important factors that predict ICU nurses’ intention to leave their job, which may result in job disengagement. Predictors found in this study may be used as outcome variables for developing such an effective method of improving nurse retention in ICUs.

Summary In order to analyse the anserine, carnosine and taurine contents in chicken essences, a high performance liquid chromatograph coupled with an electrospray ionisation (ESI) tandem mass (MS/MS) detector was used. Standards of anserine, carnosine and taurine were derivatised with dabsyl-Cl and their charged states during MS/MS analyses were detected before selected reaction monitoring (SRM) settings were determined. It was found that taurine exhibited exclusively as dabsyl-taurine with one charge at ESI+ mode. The major derivatives of anserine and carnosine showed coupling to one and two dabsyl groups, respectively, and both exhibited double charges at ESI+ mode. The SRM settings of 413 > 224, 265 > 121 and 401 > 224 were therefore selected for the dabsyl derivatives of taurine, anserine and carnosine, respectively, and they gave very good identification of those compounds found in chicken essence. The concentrations of taurine, anserine and carnosine in several commercial chicken essences determined with this MS monitoring method were much lower than those determined with traditional UV monitoring method, which was thought to result from the better identification of MS.

Examination of the collisional cooling effect of the buffer gases on ion trapping and detection in an ion trap mass spectrometer has been undertaken by the SIMION 3D program. Computation for the kinetic energy of ions under various conditions was used to account for the effects of collisional cooling of ions. Several parameters that may affect the collisional cooling effects of ions are evaluated including the existence and the variation of pressure of the buffer gas; the temperature of the ion trap; the size of the inner radius of the ion trap electrodes; the mass to charge ratio of ions; the alternative buffer gases and the qz. values which establish the ion trap trapping environment.