[Numerical simulation study on dust transport law in antibiotic raw material drug powder screening workshop].

To study the distribution pattern of drug dust in the antibiotic raw material drug powder screening workshop and improve the working environment, we used COMSOL Multiphysics 6.0 software to simulate and study the airflow distribution and dust transport law in the powder screening workshop. The results indicated that the dust in the powder screening workshop diffused rapidly with the airflow and reached a stable state at the 100th second. After the dust migrated to a stable state, the area with excessive dust concentration (dust concentration>6 mg/m(3)) widely distributed, mainly distributed in the middle and lower parts of the wall opposite the air inlet from the rotary vibrating screen. The distribution of dust showed a characteristic of local aggregation, and dust transport was related to airflow movement, which was prone to aggregation in areas with low airflow velocity and eddy currents. On the plane of the human respiratory belt height (h=1.5 m), the concentration near the dust producing surface was high, with local concentrations exceeding 32 mg/m(3). It was the key area for dust prevention and control. And the working environment can be improved by changing the air flow distribution in the workshop or other dust reduction methods.

Hyperlipidemia Impairs Osseointegration via the ROS/Wnt/ß-Catenin Pathway.

The influence of hyperlipidemia on titanium implant osseointegration and the underlying mechanisms is not well understood. This study investigates the changes in osseointegration and explores the potential mechanisms in hyperlipidemia conditions. In vivo, specialized titanium implants were implanted in the femurs of diet-induced or genetic hyperlipidemia mice. In vitro, primary murine osteoblasts were cultured on the titanium surface in high-fat medium. Results showed that hyperlipidemia led to poor osseointegration in both types of mice in vivo, and high-fat medium impaired the osteogenic differentiation of primary osteoblasts on the titanium surface in vitro. In addition, high-fat medium caused significant overproduction of reactive oxygen species (ROS) and inhibition of the Wnt/ß-catenin pathway in osteoblasts. Both N-acetyl-L-cysteine (NAC, an ROS antagonist) and Wnt3a (an activator of the Wnt/ß-catenin pathway) attenuated the poor osteogenic ability of osteoblasts. In addition, NAC reactivated the Wnt/ß-catenin pathway in osteoblasts under high-fat stimulation. These results demonstrate that hyperlipidemia impairs osseointegration via the ROS/Wnt/ß-catenin pathway and provide support for the ROS or Wnt/ß-catenin pathway as a promising therapeutic target for the development of novel drugs or implant materials to improve the osseointegration of implants in hyperlipidemic patients.

[Acute suppurative otitis media caused by pasteurella multocida :a case report].

The pasteurella multocida (PM) is widely gastrointestinal parasitic on dogs, cats and other animals. The PM human infections is caused by animal bites orits close contact. Clinically foundin focal wound infection after bite, and acute suppurative otitis media reportshave not been caused by PM. A 45 years old nasopharyngeal cancer who sudden stabbing painof the left ear for 5h. Physical examination found that the left earexisted a lot of yellowish white purulent secretion. Distribution and drug sensitivity test of bacteria showed PM and it was sensitive to many antibiotics. nasopharygo fiberscope revealed that eustachian tube and theleft ear had a large number of purulentsecretion. The main diagnosis was: ①Recurrent nasopharyngealcarcinoma; ② Acute suppurative otitis media. TREATMENT: according to the results of drug sensitive test and skin test inpatients with selection of levofloxacin (0.2 g/12 h), clindamycin (0.6 g/12 h) anti-infection treatment, the patient get better in the end.