Identification and sequencing of temperature sensitive alleles of the Anaphase Promoting Complex component mat-3 in C. elegans.

The Anaphase Promoting Complex (APC) regulates the transition from metaphase to anaphase during cell division and is important to prevent defects in chromosome segregation. In a recent temperature sensitive genetic screen looking for further genes involved in fertilization, we isolated a new temperature sensitive allele of mat-3 (as49) . We also sequenced a previously identified mat-3 ( or344 ) allele that did not previously have an annotated sequence. We determined that the as49 allele was an Alanine to Threonine (A451T) mutation in the sixth exon and the or344 mutation was a Leucine to Phenylalanine (L474F) mutation in the seventh exon. These locations of the mutant alleles are consistent with other previously annotated alleles that displayed the same metaphase to anaphase transition defect phenotype and further reinforce the importance of the tetratricopeptide repeats to mediate protein interactions.

Ferromagnetic Subwavelength Periodic Nanogroove Structure with High Magneto-Optical Kerr Effect for Sensing Applications.

The transverse magneto-optical Kerr effect (TMOKE) with gas sensing ability was comprehensively investigated in this study by directly patterning a subwavelength periodic nanogroove on a cobalt film. High-amplitude TMOKE was observed for the proposed structure, which was 243 times as intense as that of a smooth film. Further, the physical mechanism responsible for this significant improvement is elucidated by the effective activation of surface plasmon resonance at the gas-cobalt interface. The mechanism was established by investigating the electric field distributions at a resonant angle of incidence and the reflectance spectra associated with the metallic nanogroove grating structure. Moreover, we demonstrate that this scheme has a high detection sensitivity of up to 112.2° per refractive index unit and a large figure of merit, allowing the system to be integrated with microfluidics for sensing applications.

CRISPR/Cas9 Mediated Fluorescent Tagging of Caenorhabditis elegans SPE-38 Reveals a Complete Localization Pattern in Live Spermatozoa.

The Caenorhabditis elegans spe-38 gene encodes a four-pass transmembrane molecule that is required in sperm for fertilization. In previous work, the localization of the SPE-38 protein was examined using polyclonal antibodies on spermatids and mature amoeboid spermatozoa. SPE-38 is localized to unfused membranous organelles (MOs) in nonmotile spermatids. Different fixation conditions revealed that SPE-38 either localized to fused MOs and the cell body plasma membrane or the pseudopod plasma membrane of mature sperm. To address this localization paradox in mature sperm, CRISPR/Cas9 genome editing was used to tag endogenous SPE-38 with fluorescent wrmScarlet-I. Homozygous male and hermaphrodite worms encoding SPE-38::wrmScarlet-I were fertile indicating the fluorescent tag does not interfere with SPE-38 function during sperm activation or fertilization. We found that SPE-38::wrmScarlet-I localized to MOs in spermatids consistent with previous antibody localization. In mature and motile spermatozoa we found SPE-38::wrmScarlet-I in fused MOs, the cell body plasma membrane, and the pseudopod plasma membrane. We conclude that the localization pattern observed with SPE-38::wrmScarlet-I represents the complete distribution of SPE-38 in mature spermatozoa and this localization pattern is consistent with a hypothesized role of SPE-38 directly in sperm-egg binding and/or fusion.

The relationships between clinical teaching behaviour and transition shock in newly graduated nurses.

AIM: To explore the relationships between clinical teaching behaviour and transition shock in newly graduated nurses and significant differences in the northwest and northeast China. DESIGN: A cross-sectional design. METHODS: A total of 211 (nurses) and 925 (preceptors) were recruited in six Third-class different hospitals from July to August 2019. RESULTS: The transition shock is negatively correlated with the clinical teaching behaviour in northwest and northeast China, while the transition shock in the northwest is higher than that in the northeast for the behindhand economy and natural limit. CONCLUSION: The transition process of newly graduated nurses in northeast China with ethnic minorities and the behindhand economy is more difficult. For newly graduated nurses, personal health and a supportive environment need further improvement. Teaching strategies for preceptors need to be enhanced. Two-way feedback is more useful for both the newly graduated nurses and preceptors to improve quality care, and holistic care.

BRCA2 associates with MCM10 to suppress PRIMPOL-mediated repriming and single-stranded gap formation after DNA damage.

The BRCA2 tumor suppressor protects genome integrity by promoting homologous recombination-based repair of DNA breaks, stability of stalled DNA replication forks and DNA damage-induced cell cycle checkpoints. BRCA2 deficient cells display the radio-resistant DNA synthesis (RDS) phenotype, however the mechanism has remained elusive. Here we show that cells without BRCA2 are unable to sufficiently restrain DNA replication fork progression after DNA damage, and the underrestrained fork progression is due primarily to Primase-Polymerase (PRIMPOL)-mediated repriming of DNA synthesis downstream of lesions, leaving behind single-stranded DNA gaps. Moreover, we find that BRCA2 associates with the essential DNA replication factor MCM10 and this association suppresses PRIMPOL-mediated repriming and ssDNA gap formation, while having no impact on the stability of stalled replication forks. Our findings establish an important function for BRCA2, provide insights into replication fork control during the DNA damage response, and may have implications in tumor suppression and therapy response.

Clinical teaching behaviour effects professional identity and transition shock in new nurses in western china: A cross-sectional study.

AIM: To examine the interrelationship between professional identity, clinical teaching behaviour and transition shock for new nurses in Western China. DESIGN: A cross-sectional design. METHODS: A total of 779 new nurses were recruited in Gansu province and Lanzhou city from June to July 2019. Each patient was given three questionnaires to complete, and structural equation modelling was used to identify the relationships. RESULTS: The overall mean scores for the transition shock, professional identity and clinical teaching behaviour were 92.53(SD = 22.17), 89.74(SD = 16.57) 80.12(SD = 12.38), respectively. The most important aspects identified were the Physical aspect, the Sense of Mastery and Committing to Teaching. Professional identity and clinical teaching behaviour were negatively related to transition shock, a better sense of identity coupled with supportive clinical teaching were keys to a smoother journey from new to experienced nurses.

Effect of clinical teaching behaviours on transition shock in graduate nurses.

AIM: This study aimed to explore the impact of preceptor clinical teaching behaviours on transition shock in graduate nurses using bi-directional feedback between graduate nurses and clinical preceptors and to assess preceptor clinical teaching behaviours. DESIGN: This was a descriptive cross-sectional study. METHODS: This study was conducted from January-February 2019. Participants included graduate nurses (N = 117) and clinical preceptors (N = 908) from a major public tertiary hospital in Western China. RESULTS: Overall level of transition shock of graduate nurses was moderate (mean = 89 SD  17.54). Transition shock level of graduate nurses rose with the increasing of time in clinical work. Intensive care unit graduate nurses suffered the strongest transition shock, whereas surgery graduate nurses suffered the least. Graduate nurses thought that clinical preceptors were best at evaluation and feedback, whereas clinical preceptors thought they were best at showing concern and support. The primary factors associated with transition shock in graduate nurses were the time admitted to the hospital, feedback, and evaluation, use of appropriate teaching strategies, and showing concern and support, explaining 63.5% of the total variation in transition shock in graduate nurses. CONCLUSION: In Western China, where the development of economic and medical conditions lag, transition shock is a major obstacle to the professional development of graduate nurses and clinical teaching behaviours is the key to overcoming transition obstacles. However, the serious shortage of nurses makes it difficult to not only complete heavy clinical nursing work but also to undertake the teaching of students and graduate nurses. The clinical teaching system is influenced by many factors. Focusing on clinical teaching behaviours and transition shock in graduate nurses will provide valuable data for future intervention studies. IMPLICATION: The findings of this study will be of interest to managers at all levels and will enable them to support graduate nurses by engaging in excellent clinical teaching behaviours. In the clinical teaching process, giving more feedback and evaluation, improving the ability of using appropriate teaching strategies and focusing on the physical and mental health of graduate nurses may effectively decrease transition shock of graduate nurses and reduce the turnover rate.

[Study on supercritical CO2 extraction of xiaoyaosan and its GC-MS fingerprint].

To determine the optimum conditions of supercritical CO2 extraction of Xiaoyaosan, and establish its fingerprint by gas chromatography-mass spectrometry (GC-MS), the yield of extract were investigated, an orthogonal test was used to quantify the effects of extraction temperature, pressure, CO2 flow rate and time, and fingerprint analysis of different batches of extracts were by GC-MS. The optimal extraction conditions were determined as follows: extraction pressure 20 MPa, extraction temperature 50 degrees C, CO2 flow rate 25 kg x h(-1), extraction time 3 h, and average yield 2.2%. The GC-MS fingerprint was established and 27 common peaks were found, whose contents add up to 81.89% of the total peak area. Among them, 21 compounds were identified, accounting for 53.20% of the total extract. The extraction process is reasonable and favorable for industrial production. The GC-MS method is accurate, reliable, reproducible, and can be used for quality control of supercritical CO2 extract from Xiaoyaosan.