Effect of early hemostasis strategy on secondary post-traumatic sepsis in trauma hemorrhagic patients.

INTRODUCTION: Fibrinogen and platelet, as the two main components of hemostatic resuscitation, are frequently administered in traumatic massive hemorrhage patients. It is reasonable to infer that they may have an impact on post-traumatic sepsis as more and more recognition of their roles in inflammation and immunity. This study aims to determine the association between the fibrinogen/platelet transfusion ratio during the first 24 h after trauma and the risk of the post- traumatic sepsis. METHODS: We analyzed the data from the National Trauma Data Bank (NTDB). Subjects included the critically injured adult patients admitted to Level I/II trauma center from 2013 to 2017 who received fibrinogen and platelet supplementation and more than 10 units (about 4000 ml) packed red blood cells (pRBCs) during the first 24 h after trauma. Two parts of analyses were performed: (1) multivariable stepwise regression was used to determine the variables that influence the risk of post-traumatic sepsis; (2) propensity score matching (PSM), to compare the influences of different transfusion ratio between fibrinogen and platelet on the risk of sepsis and other outcomes after trauma. RESULTS: 8 features were screened out by bi-directional multivariable stepwise logistic regression to predict the post-traumatic sepsis. They are age, sex, BMI, ISSabdomen, current smoker, COPD, Fib4h/24h and Fib/PLT24h. Fib/PLT24h was negatively related to sepsis (p < 0.05). A total of 1601 patients were included in the PSM cohort and grouped by Fib/PLT24h = 0.025 according to the fitting generalized additive model (GAM) model curve. The incidence of sepsis was significantly decreased in the high Fib/PLT group [3.3 % vs 9.4 %, OR = 0.33, 95 %CI (0.17-0.60)]; the length of stay in ICU and mechanical ventilation were both shortened as well [8 (IQR 2.00,17.00) vs 9 (IQR 3.00,19.25), p = 0.006 and 4 (IQR 2.00,10.00) vs 5 (IQR 2.00,14.00), p = 0.003, respectively. CONCLUSIONS: Early and sufficient supplementation of fibrinogen was a convenient way contribute to reduce the risk of sepsis after trauma.

[Platelet Transfusion Strategies for MASPAT-Matched Platelet Transfusion Failed Patient with Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To investigate the causes of ineffectiveness of platelet transfusion with monoclonal antibody solid phase platelet antibody test (MASPAT) matching in patients with allogeneic hematopoietic stem cell transplantation and explore the strategies of platelet transfusion. METHODS: A case of donor-specific HLA antibodies (DSA) induced by transfusion which ultimately resulted in transplantation failure and ineffective platelet transfusion with MASPAT matching was selected, and the causes of ineffective platelet transfusion and platelet transfusion strategy were retrospectively analyzed. RESULTS: The 32-year-old female patient was diagnosed as acute myeloid leukemia (high risk) in another hospital with the main symptoms of fever and leukopenia, who should be admitted for hematopoietic stem cell transplantation after remission by chemotherapy. In the course of chemotherapy, DSA was generated due to platelet transfusion, and had HLA gene loci incompatible with the donor of the first transplant, leading to the failure of the first transplant. The patient received platelet transfusion for several times before and after transplantation, and the results showed that the effective rate of MASPAT matched platelet transfusion was only 35.3%. Further analysis showed that the reason for the ineffective platelet transfusion was due to the missed detection of antibodies by MASPAT method. During the second hematopoietic stem cell transplantation, the DSA-negative donor was selected, and the matching platelets but ineffective transfusion during the primary transplantation were avoided. Finally, the patient was successfully transplanted and discharged from hospital. CONCLUSIONS: DSA can cause graft failure or render the graft ineffective. For the platelet transfusion of patients with DSA, the platelet transfusion strategy with matching type only using MASPAT method will miss the detection of antibodies, resulting in invalid platelet transfusion.

Mechanism of selective induction of apoptosis of HCT116 tumor cells in circulating blood by riboflavin photochemistry.

The removal or inactivation of circulating tumor cells (CTCs) can prevent distant metastasis by hematogenous route, but there is still a lack of mature and effective technical means. In the previous research, our team has initially established a method of riboflavin photosensitized treatment (RPT) for continuous treatment of peripheral blood in vitro for the inactivation of CTCs. The core of this technology is that it can selectively induce apoptosis of CTCs (HCT116 cells) without damaging immunocyte (mainly Peripheral Blood Mononuclear Cells，PBMCs) under specific parameters. To clarify the specific mechanism, firstly, the enrichment of riboflavin in HCT116 cells and PBMCs was observed under fluorescence microscope. Secondly, the apoptotic signaling pathways in HCT116 cells and PBMCs in response to RPT treatment were analyzed by transcriptomics. Finally, the mitochondrial damage in HCT116 cells and PBMCs before and after RPT treatment was observed under electron microscope. The results showed that under the same treatment conditions, HCT116 cells were significantly enriched in riboflavin compared with PBMCs. Besides, RPT treatment reduced the expression of long non﹣coding RNA (lncRNA) NEAT1, an effector gene of HCT116 cells, which further down-regulated the expression of target gene PAX2 and promoted the expression of Bax, leading to mitochondrial outer membrane permeabilization (MOMP), and consequently increased the release of pro-apoptotic factors such as cytochrome c(Cyt C), high-temperature requirement protein A2(HTRA2), apoptosis-inducing factor (AIF), endonuclease G(ENDOG), finally leading to apoptosis of HCT116 cells. In contrast, lncRNA NEAT1 remained unchanged in PBMCs before and after RPT treatment, and was unable to stimulate the PBMCs apoptotic signaling pathway. The results of the study indicated that under the specific treatment conditions, RPT technology could selectively induce apoptosis of HCT116 cells by activating the mitochondrial apoptosis pathway, which would further provide a theoretical and technical support for the effective inactivation of CTCs by RPT technology, thereby reducing the risk of recurrence of malignant tumors and improving the cure rate of malignant tumors.

[A Novel Lyophilized PRP-Loaded Gel Based on Chitosan and PEG with Hemostatic and Antibacterial Properties].

OBJECTIVE: A dynamic gel loaded with lyophilized platelet-rich plasma-chitosan/difunctionalized polyethylene glycol (LPRP-CP) was prepared to investigate its hemostatic antibacterial and promoting wound healing of scald wounds through in vitro and in vivo experiments. METHODS: In this study, normal gauze/blank tablet (Ctrl), LPRP-CP, Chitosan HUCHUANG Powder(Chito P)and ChitoGauze XP PRO group (Chito G group) were set. The hemostatic effect and promoting healing effect of the four groups of materials were evaluated by establishing rabbit ear artery hemorrhage model and superficial Ⅱ° scalded model of skin on the back. The hemostatic time and bleeding amount were calculated and the gross and histological results of scald healing were observed. The antibacterial effect of the four groups of materials was evaluated by antibacterial test in vitro. RESULTS: In the rabbit ear arterial hemorrhage model, the hemostasis of all materials was successful. The hemostatic time of Ctrl, Chito P, LPRP-CP and Chito G groups was 213.33±38.30, 118.33±24.01, 115.00±8.37 and 111.67±11.69 s, respectively. The blood loss was 1233.83±992.27, 346.67±176.00, 193.33±121.47 and 147.50±80.66 mg, respectively. Compared with Ctrl, the hemostasis time of LPRP-CP, Chito P and Chito G group was significantly shorter (P<0.001), and the amount of blood loss of LPRP-CP and Chito G group was decreased (P<0.05). Compared with LPRP-CP, there were no significant differences in hemostatic time and blood loss between Chito P and Chito G group (P>0.05). In the model of superficial Ⅱ° scalded on the back of rabbit, the wound healing rate of LPRP-CP was faster than that of the other three groups at the same time, and the healing effect was perfect. In the antibacterial test in vitro, only LPRP-CP had better anti-S. aureus effect, and all groups had no anti-E. coli effect. CONCLUSION: LPRP-CP is an excellent hemostatic material for superficial wounds, and has certain antibacterial and wound healing effects, which has a wide academic value and research prospects.

[Preliminary Study on Screening and Identification of Lewis a Antigen Mimic Epitope in Alpaca Phage Display Nanobody Library].

OBJECTIVE: To establish a new method for synthesizing Lewis blood group antigens, that is, the mimotopes of Lewis blood group antigens were screened by using an alpaca phage display nanobody library. METHODS: We selected mimotopes of the Lewis a (lea) antigen by affinity panning of an alpaca phage display nanobody library using a monoclonal anti-lea antibody. Enzyme-linked immunosorbent assay (ELISA) was used to test the affinity of the positive clones for the monoclonal anti-lea antibody, and the high-affinity positive clones were selected for sequencing and synthesis. Finally, the sensitivity, specificity and reactivity of the synthesized lea mimotope in clinical samples were verified by ELISA. RESULTS: A total of 96 phage clones were randomly selected, and 24 were positive. Fourteen positive clones with the highest affinity were selected for sequencing. The result showed that there were 5 different sequences, among which 3 sequences with the highest frequency, largest difference and highest affinity were selected for expression and synthesis. The sensitivity and specificity of lea mimic antigen by ELISA showed that, the minimum detection limit of gel microcolumn assay (GMA) and ELISA method were 25 times different, and the lea mimic antigen had no cross reacted with the other five unrelated monoclonal antibodies(P<0.001). Finally, 30 clinical plasma samples were analyzed. The mean absorbance of the 15 positive plasma samples was significantly higher than that of the 15 negative plasma samples (P=0.02). However, the positive signal values of the clinical samples were much lower than those of the monoclonal antibodies. CONCLUSION: A new method of screening lea mimic antigen by using alpaca phage nanoantibody library has been established, which is expected to realize the screening of lea mimotopes, thus realizing the application of high-sensitivity detection methods such as ELISA and chemiluminescence in blood group antibody identification.

The Strengthening Mechanism of the Relationship between Social Work and Public Health under COVID-19 in China.

Social work and public health have always shared a common mission and vision in promoting human health. However, existing research tends to view social work and public health as two separate fields at both practice and policy levels, and these studies have largely neglected the consideration of how to integrate public health and social work. In the context of the COVID-19 epidemic, the link between the two has been strengthened and health social work has been given more importance. The question addressed in this article is through what mechanisms or practices the social work profession can strengthen its professional status and engage in interprofessional collaboration. Based on key informant interviews and case studies (one community and two cabin Hospitals), this study points out that three legitimacy mechanisms are needed: operationalizing policy, extending value, and completing justification. Furthermore, the future and possible limitations in relation to the development of health social work in China are discussed and specific recommendations are provided. Health social work needs to conduct practices and summarize its experiences and methods, to create a more friendly political environment by translating its results into policies that are conducive to the development of health social work through a political agenda. It needs to improve upon its practical abilities and methodologies, as well as professional education relating to professional values and ethics, in addition to identifying the deeper social needs of residents and discovering new, undeveloped areas of service. Moreover, because long-term change is difficult to justify due to China's policy agendas, the question of whether the professional status of health social work in the post-epidemic context can be improved is something that needs to be further explored in future studies.

[Research and Application Progress of Chitosan-based Hemostatic Materials---Review].

Whether in war or peace, timely, effective and accurate hemostasis is an important measure to improve the survival rate and cure rate of the wounded. All the countries in the world are actively developing different types of hemostatic materials so as to reduce the amount of bleeding in an emergency and create favorable conditions for subsequent transport and treatment. At present, the commercialized hemostatic materials are mainly divided into natural biological, synthetic biological, mineral and coagulation components, but all these materials have their own limitations. In this article, the characteristics of chitosan and its derivatives are reviewed as the representatives of the natural organic macromolecular polysaccharide hemostasis materials. Their molecular structures, biomedical properties, domestic and foreign research and application progress as well as comparison with applications of other hemostatic materials are involved. The further research is prospected for optimization and innovation to develop composite chitosan hemostatic materials with the function of hemostasis, antibiosis, pain relief and promoting wound healing.