[Diagnosis and orthodontic treatment strategy of complete canine transposition].

Tooth transposition is a challenge for orthodontists, especially in correcting the order of teeth. At present, the literature on transposition canines mainly focuses on epidemiological studies and case reports, and no systematic treatment guidance has been formed. In this article, the definition and classification, epidemiology and etiology, imaging diagnosis, treatment and risk control of transposed canines are systematically described in order to provide reference for clinical practice.

[Prevalence and influence factors of job burnout among hospital staffs-a cross-sectional study].

Objective: To explore the influencing factors of job burnout of medical staff and provide reference for the formulation of intervention measures. Methods: From November to December, 2018, a questionnaire survey was conducted among medical staff in a general hospital by using the research design of the current situation survey. A total of 1193 questionnaires were distributed and 939 questionnaires were returned, with a recovery rate of 78.7%, including 891 valid questionnaires and an effective recovery rate of 94.9%. Social support rating scale (SSRs) was used to evaluate social support, and Maslach Burnout Scale (MBI-GS) was used to evaluate job burnout. Single factor analysis was performed by chi square test and Fisher exact probability method. To explore the influencing factors of job burnout by using disordered multi classification logistic. Results: The average age was (27.47 ± 4.22) years old, female accounted for 71.5% (637/891) . The total physical examination rate of job burnout was 46.6%. The scores of emotional exhaustion, cynicism and decreased sense of achievement were (10.10±3.75) , (6.14±3.43) , (17.91±4.13) respectively. Multiple logistic regression analysis showed that, compared with the non detected job burnout, the young, working for 1-3 years, average sleep ≤6 hours, and poor social support were more likely to have mild job burnout (OR=0.91, 0.40, 2.25, 2.38, P<0.05) ; female, high night shift frequency in the past year, average sleep ≤6 h. Those with poor social support were more likely to have moderate to severe job burnout (OR=1.59, 2.94, 4.01, 2.40, 3.66, P<0.05) . Conclusion: Corresponding measures should be taken to reduce job burnout and improve work efficiency.

[Detection of epidermal growth factor receptor mutations using bronchial washing fluid in lung cancer patients with negative results by rapid on-site evaluation].

Objective: To evaluate the clinical application of bronchial washing fluid (BWF) in the detection of epidermal growth factor receptor (EGFR) gene mutation in lung cancer patients during diagnostic bronchoscopic procedure. Methods: Patients with suspected lung cancer lesions but failed to be identified as malignancy by rapid on-site cytologic evaluation (ROSE) were enrolled. Performed blocker PCR for EGFR mutation detection using the supernatant and cell pellet of BWF samples and compared the detective results to the EGFR mutation status detected using histologic tumor samples. Results: A total of 85 BWF and paired histological samples were collected at Fudan University Affiliated Zhongshan Hospital from October 2016 to June 2017. There were 46 male and 39 female, with a mean age of 61 years (range 30-87 years). Thirty-one patients had benign diseases and 54 patients had primary lung cancer. Among these 54 lung cancer patients, the diagnoses were made basing on bronchoscopic biopsy samples in 31 patients. The detection rate of EGFR gene mutation in BWF samples was 100.0% concordant with that using histological samples.Another 23 cases whose bronchoscopic biopsy failed to establish malignant diagnoses were further identified by other sampling methods including surgical resection, lung biopsy, etc. A total of 15 patients were identified as EGFR mutated type by pathologic detection or clinically effect assessment, and BWF could detect 11 of them, accounting for 11/15 of all cases. Overall, BWF had achieved an overall accuracy of 95.3% (81/85) comparing to paired tumor histologic samples. Conclusions: BWF is an effective complementary specimen to bronchoscopic biopsy samples in EGFR gene mutation detection in patients with suspected lung cancer lesion and negative biopsy results evaluated by ROSE during bronchoscopy.

Survivin is essential for fertile egg production and female fertility in mice.

Survivin is the smallest member of the inhibitor of apoptosis protein (IAP) family and acts as a bifunctional protein involved in mitosis regulation and apoptosis inhibition. To identify the physiological role of Survivin in female reproduction, we selectively disrupted Survivin expression in oocytes and granulosa cells (GCs), two major cell types in the ovary, by two different Cre-Loxp conditional knockout systems, and found that both led to defective female fertility. Survivin deletion in oocytes did not affect oocyte growth, viability and ovulation, but caused tetraploid egg production and thus female infertility. Further exploration revealed that Survivin was essential for regulating proper meiotic spindle organization, spindle assembly checkpoint activity, timely metaphase-to-anaphase transition and cytokinesis. Mutant mice with Survivin depleted in GCs showed reduced ovulation and subfertility, caused by defective follicular growth, increased follicular atresia and impaired luteinization. These findings suggest that Survivin has an important role in regulating folliculogenesis and oogenesis in the adult mouse ovary.

Effects of DNA damage and short-term spindle disruption on oocyte meiotic maturation.

DNA damage has recently been shown to inhibit or delay germinal vesicle breakdown (GVBD) in mouse oocytes, but once meiosis resumes, DNA-damaged oocytes are able to extrude the first polar body. In this study, using porcine oocytes, we showed that DNA damage did not affect GVBD, but inhibited the final stages of maturation, as indicated by failure of polar body emission. Unlike mitotic cells in which chromosome mis-segregation causes DNA double-strand breaks, meiotic mouse oocytes did not show increased DNA damage after disruption of chromosome attachment to spindle microtubules. Nocodazole-treated oocytes did not display increased DNA damage signals that were marked by γH2A.X signal strength, but reformed spindles and underwent maturation, although aneuploidy increased after extended nocodazole treatment. By using the mouse for parthenogenetic activation studies, we showed that early cleavage stage embryos derived from parthenogenetic activation of nocodazole-treated oocytes displayed normal activation rate and normal γH2A.X signal strength, indicating that no additional DNA damage occured. Our results suggest that DNA damage inhibits porcine oocyte maturation, while nocodazole-induced dissociation between chromosomes and microtubules does not lead to increased DNA damage either in mouse meiotic oocytes or in porcine oocytes.

A validated method for quantifying entecavir in biological matrices and its application in a pharmacokinetic study in rats and dogs.

A sensitive and specific liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) method that uses ganciclovir as an internal standard (IS) has been developed and validated for quantifying entecavir in rat and dog plasma. Following solid-phase extraction (SPE), the analytes were separated on an Inertsil® ODS-3 (5 µm, 150 mm × 2.1 mm i.d.) column and analyzed in selected ion monitoring (SIM) mode with a positive electrospray ionization (ESI) source using the [M+H]+ ions, 278.1 for entecavir and 256.0 for ganciclovir. The method was validated over the concentration range of 0.01-9 µg/mL for entecavir. All precisions (RSD) within and between batches were less than 10%, and accuracies ranged from 98.1 to 102.5%. The lower limit of quantification was 0.01 µg/mL. The extraction recovery averaged 93.9-96.7%. The validated method was used for a pharmacokinetic study of entecavir in rats and dogs. The following pharmacokinetic parameters were obtained for rats and dogs, respectively: the area under the plasma concentration vs. time curves from time 0 to 24 h (AUC0-24) were 15.4 ± 4.5 and 23.4 ± 7.2 µg∙h/mL; the mean maximum plasma concentration (Cmax) were 2.4 ± 0.8 and 5.0 ± 0.9 µg/mL; the mean time to reach the maximum plasma concentrations (Tmax) were 1.7 ± 0.7 and 1.5 ± 0.4 h; and the mean elimination half-life (t1/2) were 5.3 ± 1.4 and 3.8 ± 1.3 h.

Pharmacokinetics, distribution and excretion of PNA in rat by liquid chromatography mass spectrometry method.

The pharmacokinetic profiles, tissue distribution and excretion patterns of PNA in healthy male and female Sprague-Dawley rats following a single intra-duodenum administration were investigated by previously established LC-MS method. Absorption was rapid in rats as evidenced by a short time to maximum concentration (Cmax) of 0.050 ± 0.021, 0.072 ± 0.017 and 0.067 ± 0.018 h at the 25, 50 and 100 mg/kg dose level, respectively. The Cmax were 754.9 ± 196.1, 1187.8 ± 642.1 and 2082.1 ± 1,278.5 ng/mL and the AUC0-4 were 71.8 ± 25.9, 135.2 ± 69.9 and 303.3 ± 198.3 µg/L h, which showed linear with the intra-duodenum administration range from 25-100 mg/kg. Tissues were collected at 4 time points (3, 10 min, 1 and 3 h) after dosing at 50 mg/kg. Compare to the concentrations of plasma and other tissues, the level was particularly high in the liver and brain during 3 h. Bile/urine and feces samples were collected before dosing and till 24/48 h post-dosing. The mean cumulative excretion of unchanged PNA in bile amounted to 0.021% of the dose up to 24 h. The mean recoveries of unchanged PNA were 0.0095% and 0.043% of the dose up to 48 h in urine and feces, respectively. There was no significant difference in PNA concentration observed between male and female rats during the experiments.