An analysis of the optimal intrusion force of the maxillary central incisor with root horizontal resorption using the finite element method and curve fitting.

There are no studies on the optimal intrusion force in orthodontic patients with the existing root resorption (RR). The study aimed to analyze the optimal intrusion force for central incisors with existing horizontal root resorption using the finite element method (FEM). We calculated the optimal intrusion force using the finite element method and curve fitting. We found that with the increase of the maxillary central incisor's root horizontal resorption length, the optimal intrusion force interval's median gradually increases. If the resorption length is more significant than 1/2 of the root length, it is not recommended to use intrusion force theoretically.

Synthesis of 1α,25-dihydroxyvitamin D3 analogues with α,α-difluorocycloketone at the CD-ring side chains and their biological properties in ovariectomized rats.

Two novel 1α,25-dihydroxyvitamin D3 derivatives containing a α,α-difluorocyclopentanone (3) or α,α-difluorocyclohexanone (4) moiety at the CD-ring side chains were designed, synthesized, and evaluated for their biological properties on restoring bone mass in ovariectomized (OVX) rats with established osteopenia. The synthesis of compounds 3 and 4 utilized the Wittig-Horner coupling to build up the vitamin D conjugated triene system, followed by the introduction of the cycloketone fragments at the side chain, and subsequent α,α-difluorination of the ketone by the treatment of the derived silyl enol ether with Selectfluor, as the key synthetic steps. In comparison with the natural 1α,25-dihydroxyvitamin D3 (calcitriol; 200 ng/kg/day), oral administration of compounds 3 and 4 at the dose of 25 ng/kg/day for 6 weeks led to much improved bone mass and bone density related parameters, while maintaining normal serum calcium and serum phosphorus levels. The immunohistochemistry results showed that both compounds remarkably decreased in osteoclast number and moderately decreased in osteoblast number on trabecular bone surface. Therefore, our findings suggested that compounds 3 and 4 successfully rescue bone loss by suppression on bone turnover in OVX rat models.

Patient safety climate in general public hospitals in China: differences associated with department and job type based on a cross-sectional survey.

OBJECTIVE: This study analysed differences in the perceived patient safety climate among different working departments and job types in public general hospitals in China. DESIGN: Cross-sectional survey. SETTING: Eighteen tertiary hospitals and 36 secondary hospitals from 10 areas in Shanghai, Hubei Province and Gansu Province, China. PARTICIPANTS: Overall, 4753 staff, including physicians, nurses, medical technicians and managers, were recruited from March to June 2015. MAIN OUTCOME MEASURE: The Patient Safety Climate in Healthcare Organisations (PSCHO) tool and the percentages of 'problematic responses' (PPRs) were used as outcome measures. Multivariable two-level random intercept models were applied in the analysis. RESULTS: A total of 4121 valid questionnaires were collected. Perceptions regarding the patient safety climate varied among departments and job types. Physicians responded with relatively more negative evaluations of 'organisational resources for safety', 'unit recognition and support for safety efforts', 'psychological safety', 'problem responsiveness' and overall safety climate. Paediatrics departments, intensive care units, emergency departments and clinical auxiliary departments require more attention. The PPRs for 'fear of blame and punishment' were universally significantly high, and the PPRs for 'fear of shame' and 'provision of safe care' were remarkably high, especially in some departments. Departmental differences across all dimensions and the overall safety climate primarily depended on job type. CONCLUSIONS: The differences suggest that strategies and measures for improving the patient safety climate should be tailored by working department and job type.