Adipose-derived stem cells(ASCs)have become important seed cells in tissue engineering,because of their unique advantages.Extensive research has been conducted to determine the ideal method of cryopreservation for ASCs.In this review,we summarize the basic cryobiology and cryopreservation protocols for ASCs,and look forward to future research into cryopreservation protocols for ASCs.

Adipose-derived stem cells(ASCs)have become important seed cells in tissue engineering,because of their unique advantages.Extensive research has been conducted to determine the ideal method of cryopreservation for ASCs.In this review,we summarize the basic cryobiology and cryopreservation protocols for ASCs,and look forward to future research into cryopreservation protocols for ASCs.

ObjectiveTo investigate the promotional effect of astragaloside on the repair and healing of chronic non-healing wounds and its mechanism. MethodA total of 60 male SD rats were constructed with full-layer skin defect wounds on the back， and except for the control （Con） group， the rest were constructed with non-healing wounds， which were then randomly divided into the sham-operation （sham） group， the low-dose astragaloside group， the high-dose astragaloside group， the astragaloside + LY294002 ［phosphatidylinositol 3-kinase （PI3K） inhibitor］ group， and the astragaloside + EX527 ［silencing regulatory protein 1 （SIRT1） inhibitor］ group. The percentage of wound area in each group was observed on the 2nd， 4th， 6th， and 8th days after wound molding. Collagen type Ⅰ alpha 1 （COL1A1） and alpha smooth muscle actin （α-SMA） expressions in the wound tissue were detected by immunofluorescence. Hematoxylin and eosin （HE） staining was performed to determine the pathological structure of the wound. The mRNA expression of inflammatory factors in the wound was measured by real-time polymerase chain reaction （Real-time PCR）， and the expression of proteins related to the SIRT1/ nuclear factor （NF）-κB and PI3K/protein kinase B （Akt） signaling pathways in the wound was tested by Western blot. ResultCompared with the sham group， the percentage of postoperative wound area of rats in both low-dose and high-dose astragaloside groups gradually decreased with time， and the efficacy of the high-dose astragaloside group was better. Compared with the Con group， the fluorescence intensity of COL1A1 in wound tissue of the sham group decreased， while the expression of α-SMA increased. The epithelial tissue was severely damaged， with an increase in the thickness， and a large number of inflammatory cells were seen in the infiltration. The mRNA expression of tumor necrosis factor （TNF）-α， interleukin （IL）-1β， IL-6， and inducible nitric oxide synthase （iNOS） was elevated. The protein expression of NF-κB p65， p-PI3K/PI3K， and p-Akt/Akt was elevated， while SIRT1 expression was decreased （P<0.05）. Compared with the sham group， the fluorescence intensity of COL1A1 and α-SMA increased after astragaloside treatment. The number of epithelial cells increased， and the thickness decreased. The inflammatory cells decreased， and the amount of collagen increased. The mRNA expression of TNF-α， IL-1β， IL-6， and iNOS was decreased， and the protein expression of NF-κB p65， p-PI3K/PI3K， and p-Akt/Akt was decreased. SIRT1 was elevated， and the effect was better in the high-dose astragaloside group （P<0.05）. Compared with the high-dose astragaloside group， inhibition of the PI3K/Akt and SIRT1 pathways by LY294002 and EX527 prevented the therapeutic efficacy of astragaloside on chronic non-healing wounds. ConclusionThe topical application of astragaloside significantly promotes the healing of chronic non-healing wounds in rats， and the mechanism may be related to the activation of the PI3K/Akt pathway and the SIRT1/NF-κB pathway.

BACKGROUND:Previous literature reported that the fusion cage moved more than 2 mm from its original position,which means that the fusion cage moved backward.At present,clinical observation has found that the factors leading to the displacement of the fusion cage are complex,and the relationship between these factors and the cage retropulsion is not clear. OBJECTIVE:To explore the risk factors related to cage retropulsion after lumbar interbody fusion. METHODS:Retrospective analysis was conducted in 200 patients who underwent transforaminal lumbar interbody fusion surgery with a polyetheretherketone interbody fusion from February 2020 to February 2022.According to the distance from the posterior edge of the vertebral fusion cage to the posterior edge of the vertebral body after the operation(the second day after the removal of the drainage tube)and 1,3,6 and 12 months after the operation,patients were divided into cage retropulsion group(≥2 mm)and cage non-retropulsion group(<2 mm).The factors that may affect cage retropulsion,such as age,gender,body mass index,bone mineral density,operation time,bleeding,endplate injury,preoperative and postoperative interbody height,cage implantation depth,cage size,and segmental anterior convexity angle,were analyzed by univariate and logistic regression analysis. RESULTS AND CONCLUSION:(1)Posterior displacement of the fusion cage occurred in 15 cases(15/200).The differences in basic information such as age and body mass index between the two groups were not statistically significant.(2)The results of the univariate analysis were that gap height difference,time to wear a brace,segmental anterior convexity angle difference,bone mineral density,and age were related to posterior migration of the cage.(3)The results of logistic regression analysis were that cage size,endplate injury condition,and depth of cage implantation were risk factors for cage retropulsion.(4)These findings suggest that cage retropulsion after lumbar interbody fusion is caused by multiple factors,including segmental anterior convexity angle difference,bone mineral density,cage size,endplate damage,time to wear a brace,and depth of cage implantation.

Objective:To study the infection and epidemiological characteristics of soil borne nematode disease in Sihong County, Suqian City, and to provide scientific basis for further development of prevention and control measures.Methods:In 2022, according to geographic location, Sihong County was divided into east and west areas. Jieji Town, Shiji Township, and Linhuai Town were selected from the east area, and Tianganghu Township, Meihua Town from the west area. One administrative village was selected as a survey point in each township. Using cluster sampling method, 450 permanent residents aged 3 years old and older in the village were selected as the respondents for questionnaire survey and fecal sample collection. The infection status of hookworms, roundworms, whipworms and pinworms in fecal samples were examined, transparent tape anal swab method for detecting pinworm eggs in children, and influencing factors were analyzed.Results:A total of 2 264 survey subjects were included, 18 cases of soil borne nematodes were detected as positive, with an overall positive rate of 0.80%. Among them, 15 cases were positive for hookworms, 1 case was positive for whipworms, and 2 cases were positive for pinworms, with detection rates of 0.66%, 0.04%, and 0.09%, respectively. No ascaris lumbricoides were detected. Transparent tape anal swab method was used to examine 142 children, and the positivity rate of 1.41% (2/142). By township, the detection rate of soil borne nematodes was the highest in Jieji Town, at 2.41% (11/457); the others were Meihua Town, Tianganghu Township, Shiji Township, and Linhuai Town, with detection rates of 0.89% (4/451),0.66% (3/454), 0 (0/451) and 0 (0/451), respectively. There was a statistically significant difference between different townships (χ 2 = 19.21, P < 0.001). Among the 18 positive cases of soil borne nematode, 7 were males and 11 were females, with detection rates of 0.66% (7/1 063) and 0.92% (11/1 201), respectively, the difference was not statistically significant (χ 2 = 0.47, P = 0.491). The age distribution showed the highest detection rate in the 40 - < 60 age group, at 1.42% (9/634), with statistically significant differences between different age groups (χ 2 = 6.41, P = 0.033). The occupational distribution showed the highest detection rate in farmers, at 1.46% (9/617), with statistically significant differences between different professions (χ 2 = 8.00, P = 0.034). The differences in total soil borne nematode and hookworm detection rates were statistically significant among different methods of treating human and animal feces (χ 2 = 11.01, 9.02, P = 0.003, 0.011). Conclusions:The main species of soil borne nematode infections in Sihong County, Suqian City are hookworms, with fewer infections of whipworms and pinworms, and no roundworm infections observed. There are regional differences in detection rate. In the future, it is necessary to strengthen health education for key populations, enhance health knowledge publicity, and effectively intervene to change unhealthy production and lifestyle, further reducing the infection of soil borne nematodes in Suqian City.

Objective:To explore the airway pathogen characteristics and examine the correlation between donor-derived pathogens and post-transplant outcomes in patients after lung transplantation (LT).Methods:Between January 1, 2015 and December 31, 2019, retrospective review was conducted for clinical and microbiological data of 88 LT recipients.Airway pathogen percentage of different microorganisms and evolution of drug-resistance were examined.Drug-resistant pathogen positive group (n=71) and negative group (n=17) were assigned according to whether or not drug-resistant pathogens were detected.Survival analysis was conducted by Log-rank with 3-year follow-ups.Between April 11, 2020 and September 5, 2020, prospective study was conducted in 14LT recipients.The potential pathogenic bacteria from donor lungs were detected by metagenomic next generation sequencing and the impact of those bacteria was examined on 1-year post-transplantation outcome in 2020.Microbial diversity and richness were shown with Shannon index.The outcome variables included heart rate, neutrophil count, lymphocyte count, immunoglobulin level and pulmonary spirometry.ANOVA and Pearson's correlation analysis were performed for elucidating the relationship between airway microbiota and post-LT outcomes.Results:From 2015 to 2019, 88 recipients were recruited and 992 strains of airway pathogens were isolated, including bacteria 796 strains and fungi 196 strains.Gram-negative bacteria (704 strains) accounted for 88.4% of all bacteria.The detection rates of Gram-positive bacteria, Klebsiella pneumonia (Kp), Acinetobacter baumannii (Ab), Stenotrophomonas maltophilia and Candida increased in 2019 than that in 2015 (8.2% vs. 5.3%, 13.6% vs. 13.2%, 33.2% vs. 17.5%, 6.5% vs. 5.3%, 26.6% vs. 20.2%). Drug resistance rate of Kp to imipenem was 68.18% in 2019 and drug resistance rate of Ab to imipenem 98.44%.The 3-year survival rate was 46.3% and 35.3% in drug-resistance positive and negative groups and the difference was insignificant ( P=0.410). Fourteen recipients were enrolled in 2020.Potential pathogenic bacteria could be detected in all donor samples.Five recipients carried the same bacteria and two died during 1-year follow-up.Nine recipients did not carry the donor-derived pathogens and two died during 1-year follow-up.The diversity of donor/recipient-derived airway microbiota (Shannon index) showed no correlation with the outcomes of 1-year follow-up by Pearson's correlation test. Conclusions:Gram-negative bacteria predominated in airway pathogens of recipients post-LT.The drug resistance rate to imipenem remained high.The donor/recipient-derived pathogen isolates showed no correlation with immediate outcomes post-LT.

Objective:To analyze the protective effect of dust masks worn by super absorbent polymer (SAP) dust-exposed workers and the influence of each test exercise on the protective effect of mask.Methods:In March 2017, forty nine SAP dust-exposed workers in a large chemical enterprise were selected as subjects. The respirator fitness tester was used to test the protective effect of dust mask before and after training, and the influence of each test exercise on the protective effect of dust mask was analyzed.Results:After training, the qualified rate of dust mask protective effect of SAP dust-exposed workers was 95.92% (47/49) , which was significantly higher than that before training [63.31% (32/49) ], and the difference was statistically significant (χ 2=14.69, P<0.01) . When the total protective effect was qualified, the fit factor ( FF) decreased significantly when speaking aloud and bending down ( Z=-2.59, -4.20, P<0.01) . The qualified rates of protective effect of each exercise were significantly different (χ 2=42.70, P<0.01) , among which the qualified rates of deep breath was the highest (100.00%) , and the qualified rate of bending down was the lowest (70.21%) . Conclusion:Strengthening the training of workers to wear masks correctly is helpful to improve their respiratory protection efficiency. Under the condition that the total protective effect of dust masks is qualified, workers should try to avoid unnecessary actions, especially speaking aloud and bending down frequently.

Objective:To analyze the protective effect of dust masks worn by super absorbent polymer (SAP) dust-exposed workers and the influence of each test exercise on the protective effect of mask.Methods:In March 2017, forty nine SAP dust-exposed workers in a large chemical enterprise were selected as subjects. The respirator fitness tester was used to test the protective effect of dust mask before and after training, and the influence of each test exercise on the protective effect of dust mask was analyzed.Results:After training, the qualified rate of dust mask protective effect of SAP dust-exposed workers was 95.92% (47/49) , which was significantly higher than that before training [63.31% (32/49) ], and the difference was statistically significant (χ 2=14.69, P<0.01) . When the total protective effect was qualified, the fit factor ( FF) decreased significantly when speaking aloud and bending down ( Z=-2.59, -4.20, P<0.01) . The qualified rates of protective effect of each exercise were significantly different (χ 2=42.70, P<0.01) , among which the qualified rates of deep breath was the highest (100.00%) , and the qualified rate of bending down was the lowest (70.21%) . Conclusion:Strengthening the training of workers to wear masks correctly is helpful to improve their respiratory protection efficiency. Under the condition that the total protective effect of dust masks is qualified, workers should try to avoid unnecessary actions, especially speaking aloud and bending down frequently.

OBJECTIVETo compare the efficacy and safety between laparoscopic total extraperitoneal prosthetic (TEP) and Lichtenstein herniorrhaphy in the treatment of inguinal hernia (IH).

METHODSClinical data of 158 IH patients at our hospital from October 2015 to October 2016 were retrospectively analyzed. Among 158 patients, 85 patients underwent TEP (TEP group), and 73 underwent Lichtenstein herniorrhaphy(Lichtenstein group). Patients of TEP group received general anesthesia. The space between suprapubic space and iliac fossa was separated with attention to protect the spermatic cord during the operation so as to avoid excessive separation. When the patch was placed, the internal margin exceeded the contralateral pubic tubercle, the lateral margin reached the anterior superior iliac spine, there was at least 2 cm overlap between the superior margin and the joint tendon, the lower margin was inserted into the suprapubic bladder space(Retzius space), and the lateral lower margin was at least 6 cm to internal ring. Lichtenstein group received local anesthesia or continuous epidural anesthesia and all underwent routine Lichtenstein herniorrhaphy. Operative time, postoperative conditions and recurrence were compared between two groups.

RESULTSAmong these 158 patients, 129 were male and 29 were female, with an age ranging from 26 to 75 years (median 42 years). Baseline data were not significantly different between two groups(all P>0.05). There was no perioperative death and serious complications in two groups. The difference was not statistically significant in operative time[(47.6±5.4) minutes vs. (48.9±6.3) minutes, t=0.238, P=1.024]. But TEP group was better than Lichtenstein group in terms of intraoperative blood loss [(7.53±2.31) ml vs. (11.41±4.49) ml, t=5.783, P=0.032], postoperative bedtime [(1.25±0.32) days vs. (2.83±0.52) days, t=5.294, P=0.041], postoperative hospital stay [(2.38±1.14) days vs. (3.46±1.81) days, t=5.482, P=0.037], and postoperative pain score (1.27±0.47 vs. 3.42±1.93, t=5.639, P=0.034). Follow-up was 12-16 months (median 10 months). In TEP and Lichtenstein group after operation, incision infection occurred in both 1 case, edema of the scrotum or labia minora developed in 2 patients and 3 cases respectively, chronic pain was found in one and 2 cases respectively. The patients were followed up for 5 to 16 months(median 10 months), and recurrences was observed in 1 case both in TEP group and Lichtenstein group respectively.

CONCLUSIONLaparoscopic total extraperitoneal prosthetic is safe and effective in the treatment of inguinal hernia, which is better than Lichtenstein herniorrhaphy in fast recovery, less trauma and more comfort, and worthy of clinical promotion.

Objective:To isolate SD rat adipose-derived stem cells(ASCs)by suspended explant culture method.Methods: The healthy rat inguinal fat pads were obtained.The SD rat ASCs were isolated by suspended explant culture method and explant adherent culture method.The growth status and morphology were observed.The growth curve and cell surface markers CD29,CD44,CD45 of the 3rd passage cells were analyzed respectively by CCK-8,immunocytochemistry;the 3rd passage cells were induced individually by adipogenic differentiation medium and osteogenic differentiation medium,and cells were examined by oil red O staining and alizarin red staining.Results: The SD rat ASCs obtained by the two methods exhibited a spindle-shaped appearance and could rapidly expand.The cell growth curves were typical of S type.Immunocytochemistry analysis revealed that the third passage of SD rat ASCs were positive for CD29,CD44,but were negative for CD45.SD rat ASCs were positive for oil red O staining at 14 days after adipogenic induction,and positive for alizarin red staining at 14 days after osteogenic induction.Conclusion: Isolation of SD rat ASCs by suspended explant culture method is successfully established.The method is simple.It provides a new method for the isolation of SD rat ASCs in vitro.