OBJECTIVETo study the effect of activated microglia grafting on rats' hind limb motor function recovery after spinal cord injury.

METHODSMicroglia were separated from primary culture and subcultured for 3 generations. Lipopolysaccharide was added to the culture medium with the terminal concentration of 10 microl/L for microglia activation 3 days before transplantation. Totally 80 adult Wistar rats were divided into transplantation group and control group, with 40 rats in each group. Spinal cord injury model of rats was set by hitting onto the spinal cord using a modified Allen impactor. With a 5 microl micro-syringe, the activated microglia suspension was injected into the injured area 7 days after the first operation. Basso, Beattie and Bresnahan (BBB) scoring for hind limb motor function was taken on the 1st, 7th, 14th, 21st, and 28th day after microglia transplantation, and 8 rats were sacrificed at each time point mentioned above, respectively. Frozen sections of the spinal cord were made for haematoxylin-eosin (HE) and Naoumenko-Feigin stainings. SPSS 11.0 software was used for statistical analysis.

RESULTSBBB scores for hind limb motor function on the 14th, 21st, and 28th day were significantly higher compared with the control group. Most liquefaction necrosis areas disappeared and only a few multicystic cavities surrounded by aggregated microglia remained in the transplantation group. Naoumenko-Feigin staining for microglia showed that the transplantation group had significantly more positive cells (P < 0.05).

CONCLUSIONSGrafting of activated microglia into the injured spinal cord can significantly promote the hind limb motor function recovery in rats with spinal cord injury and reduce the size of liquefaction necrosis area. The extent of lower limb motor function improvement has a positive correlation with the number of aggregated microglia.

Animals ; Antigens, CD ; analysis ; Antigens, Differentiation, Myelomonocytic ; analysis ; Cells, Cultured ; Flow Cytometry ; Fluorescent Antibody Technique, Indirect ; Hindlimb ; physiopathology ; Immunohistochemistry ; Microglia ; transplantation ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Spinal Cord Injuries ; immunology ; physiopathology ; therapy

BACKGROUNDThis study aimed to evaluate the effects of standard rescue procedure (SRP) in improving severe trauma treatments in China.

METHODSThis study was conducted in 12 hospitals located in geographically and industrially different cities in China. A standard procedure on severe trauma rescue was established as a general rule for staff training and patient treatment. A regional network (system) efficiently integrating prehospital rescue, emergency room treatments, and hospital specialist treatments was built under the rule for information sharing and improving severe trauma treatments. Treatment outcomes were compared between before and 1 year after the implementation of the SRP.

RESULTSThe outcomes of a total of 74,615 and 12,051 trauma cases were collected from 12 hospitals before and after the implementation of the SRP. Implementation of the SRP led to efficient cooperation and information sharing of different treatment services. The emergency response time, prehospital transit time, emergency rescue time, consultation call time, and mortality rate of patients were 24.24 ± 4.32 min, 45.69 ± 3.89 min, 6.38 ± 1.05 min, 17.53 ± 0.72 min, and 33.82% ± 3.87% (n = 441), respectively, before the implementation of the standardization and significantly reduced to 10.11 ± 3.21 min, 22.39 ± 4.32 min, 3.26 ± 0.89 min, 3.45 ± 0.45 min, and 20.49% ± 3.11%, separately (n = 495, P < 0.05) after that.

CONCLUSIONSStaff training and SRP can significantly improve the efficiency of severe trauma treatments in China.

Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; China ; Emergency Medical Services ; standards ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Wounds and Injuries ; Young Adult

Objective: To investigate a SARS-CoV-2 epidemic reported in Rongcheng City, Weihai, Shandong Province. Methods: The SARS-CoV-2 nucleic acid positive patients and their close contacts were investigated, and the whole genome sequencing and genetic evolution analysis of 9 variant viruses were carried out. An infection source investigation and analysis were carried out from two sources of home and abroad, and three aspects of human, material and environment. Results: A total of 15 asymptomatic infections were reported in this epidemic, including 13 cases as employees of workshop of aquatic products processing company, with an infection rate of 21.67% (13/60). Two cases were infected people's neighbors in the same village (conjugal relation). The first six positive persons were processing workers engaged in the first process of removing squid viscera in the workshop of the company. The nucleic acid Ct value of the first time were concentrated between 15 and 29, suggesting that the virus load was high, which was suspected to be caused by one-time homologous exposure. The whole genome sequence of 9 SARS-CoV-2 strains was highly homologous, belonging to VOC/Gamma (Lineage P.1.15). No highly homologous sequences were found from previous native and imported cases in China. It was highly homologous with the six virus sequences sampled from May 5 to 26, 2021 uploaded by Chile. The infection source investigation showed that the company had used the squid raw materials captured in the ocean near Chile and Argentina from May to June 2021 over the last 14 days. Many samples of raw materials, products and their outer packages in the inventory were tested positive for nucleic acid. Conclusion: This epidemic is the first local epidemic caused by the VOC/Gamma of SARS-CoV-2 in China. It is speculated that the VOC/Gamma, which was prevalent in South America from May to June 2021, could be imported into China through frozen squid.
Humans ; SARS-CoV-2 ; COVID-19 ; Epidemics ; China/epidemiology*