【Objective】 To establish the internal quality control standard of leukocyte-depleted suspended red blood cell volume in our center, so as to guide the preparation of components, strengthen the internal quality control and improve the quality of blood preparations. 【Methods】 A total of 1 523 bags of whole blood collected using two manufacturers′ leukocyte-depleted blood bags from March to August 2023 at our center were extracted. The blood before and after filtration were weighed, and the volume of whole blood collected, the volume of filtration loss and the product volume based on the formula and measured specific gravity were calculated. According to the data distribution characteristics, the reference range of leukocyte-depleted suspended red blood cell volume was determined, and the differences of whole blood collection volume, filtration loss capacity and product capacity between the two manufacturers were analyzed. The quality control data of leukocyte-depleted red blood cells over the past year with the difference between another 100 bags of these cells and the reference interval were compared, and the effectiveness of reference interval was validated. 【Results】 The median whole blood collection volume in the sample size was 402.0 mL, with a median filtration loss of 42.4 mL, and an average volume of leukocyte-depleted suspended red blood cells at 322.5 mL. The whole blood collection volume (A: median 404.4 mL; B: median 397.7 mL, P<0.01) and the volume of leukocyte-depleted suspended red blood cell products (A: mean 331.4 mL; B: mean 312.0 mL, P<0.01) using manufacturer A′s leukocyte-depleted blood bag were both higher, with a lower filtration loss capacity (A: median 39.5 mL; B: median 46.6 mL, P<0.01). The standard deviation of the volume of leukocyte-depleted suspended red blood cell was 19.6, and the reference interval was 284.1-360.9 mL. The validation samples and quality control sampling data showed no difference from the interval samples (P>0.05). 【Conclusion】 According to the actual situation of our center, the volume standard of leukocyte-depleted suspended red blood cells in our center is determined to be 284.1-360.9 mL.

Objective To construct c-Met CAR-T cells secreting PD-1 antibodies to reduce immune inhibitory effect of tumor cells and enhance the efficacy of CAR-T cell therapy against pancreatic cancer.Methods Kaplan-Meier Plotter,GEPIA,and Timer 2.0 bioinformatics databases were used to analyze c-Met expression in pancreatic cancer and its correlation with survival and immune infiltration status.In clinical samples of pancreatic cancer and pancreatic cancer Aspc-1 cells,c-Met and PD-L1 expressions were detected using immunohistochemistry or flow cytometry.Using gene editing technology,PD-1 secretory antibodies and HIS tags were linked to second-generation c-Met CAR molecules to construct PD-1/c-Met CAR plasmids,which were then packaged into lentiviruses for infection of activated T cells.The positive rate and cell subset distribution of CAR-T cells were analyzed with flow cytometry,and secretory PD-1 antibodies in cell supernatants were detected using Western blotting.The target cell killing efficiency and proliferative activity of the modified CAR-T cells were evaluated after activation,and cytokine secretion was analyzed using ELISA.Results The expression of c-Met was significantly higher in pancreatic cancer than in normal tissues,and its expression level was negatively correlated with the patients'survival and positively correlated with immune cell infiltration.The clinical samples of pancreatic cancer tissues expressed significantly higher levels of c-Met and PD-L1 than the adjacent tissues,and 90.7%and 57.7%of Aspc-1 cells were positive for c-Met and PD-L1,respectively.The constructed PD-1/c-Met CAR-T cells were capable of secreting PD-1 antibodies and showed a significantly higher killing efficiency against tumor cells than c-Met CAR-T cells at an effector-to-target ratio of 20:1,with also a higher proliferative activity after target cell stimulation and higher levels of IL-2 and TNF-α secretin.Conclusion PD-1/c-Met CAR-T cells have higher killing efficiency against pancreatic cancer cells with also higher proliferative activity than c-Met CAR-T cells.

Objective To construct c-Met CAR-T cells secreting PD-1 antibodies to reduce immune inhibitory effect of tumor cells and enhance the efficacy of CAR-T cell therapy against pancreatic cancer.Methods Kaplan-Meier Plotter,GEPIA,and Timer 2.0 bioinformatics databases were used to analyze c-Met expression in pancreatic cancer and its correlation with survival and immune infiltration status.In clinical samples of pancreatic cancer and pancreatic cancer Aspc-1 cells,c-Met and PD-L1 expressions were detected using immunohistochemistry or flow cytometry.Using gene editing technology,PD-1 secretory antibodies and HIS tags were linked to second-generation c-Met CAR molecules to construct PD-1/c-Met CAR plasmids,which were then packaged into lentiviruses for infection of activated T cells.The positive rate and cell subset distribution of CAR-T cells were analyzed with flow cytometry,and secretory PD-1 antibodies in cell supernatants were detected using Western blotting.The target cell killing efficiency and proliferative activity of the modified CAR-T cells were evaluated after activation,and cytokine secretion was analyzed using ELISA.Results The expression of c-Met was significantly higher in pancreatic cancer than in normal tissues,and its expression level was negatively correlated with the patients'survival and positively correlated with immune cell infiltration.The clinical samples of pancreatic cancer tissues expressed significantly higher levels of c-Met and PD-L1 than the adjacent tissues,and 90.7%and 57.7%of Aspc-1 cells were positive for c-Met and PD-L1,respectively.The constructed PD-1/c-Met CAR-T cells were capable of secreting PD-1 antibodies and showed a significantly higher killing efficiency against tumor cells than c-Met CAR-T cells at an effector-to-target ratio of 20:1,with also a higher proliferative activity after target cell stimulation and higher levels of IL-2 and TNF-α secretin.Conclusion PD-1/c-Met CAR-T cells have higher killing efficiency against pancreatic cancer cells with also higher proliferative activity than c-Met CAR-T cells.

Objective To investigate the application value of point-of-care lung ultrasound (POC-LUS) scoring in selecting respiratory support treatment modalities for neonatal infectious pneumonia (NIP). Methods A total of 89 NIP patients were selected as the study subjects and divided into control group (no assisted ventilation) with 46 cases, noninvasive group (noninvasive assisted ventilation) with 28 cases, and invasive group (invasive mechanical ventilation) with 15 cases based on the degree of dyspnea and blood gas analysis results. The POC-LUS scores of the three groups were compared, and the correlations of POC-LUS scores with arterial oxygen partial pressure [p_a(O₂)] and arterial carbon dioxide partial pressure [p_a(CO₂)] were analyzed. Receiver operating characteristic (ROC) curves were plotted to assess the predictive efficacy of POC-LUS scores for the need for noninvasive assisted ventilation or invasive mechanical ventilation in NIP patients. Results The POC-LUS scores of the noninvasive group and the invasive group were (31.7±7.3) and (42.1±8.0), respectively, which were higher than (21.5±7.3) of the control group. Additionally, the score of the invasive group was higher than that of the noninvasive group (P < 0.05). Correlation analysis revealed a significant negative correlation between POC-LUS scores and p_a(O₂) (r=-0.802, P < 0.05), and a significant positive correlation with p_a(CO₂) (r=0.807, P < 0.05). ROC curve analysis showed that the area under the curve (AUC) of POC-LUS scores for predicting the need for noninvasive assisted ventilation and invasive mechanical ventilation were 0.918 (95%CI, 0.862 to 0.973) and 0.938 (95%CI, 0.889 to 0.987), respectively. The sensitivity was 0.767 and 0.933, and the specificity was 0.935 and 0.824, with optimal cutoff values of 29.5 and 31.5, respectively. Conclusion POC-LUS scoring can quantitatively assess the severity of lung lesions in NIP patients and serves as a guiding tool for clinicians in selecting assisted ventilation treatment modalities.

OBJECTIVE: To investigate the effect of human subcutaneous adipose-derived stem cells (hADSCs) local transplantation on orthodontically induced root resorption (OIRR) and provide theoretical and experimental basis for the clinical application of hADSCs to inhibit OIRR. METHODS: Forty 8-week-old male Sprague Dawley rats were randomly divided into experimental group and control group, with 20 rats in each group, to establish the first molar mesial orthodontic tooth movement (OTM) model of rat right maxillary. The rats in the experimental group were injected with 25 μL of cell suspension containing 2.5×10 ⁵ hADSCs on the 1st, 4th, 8th, and 12th day of modeling, while the rats in the control group were injected with 25 μL of PBS. The rat maxillary models were obtained before and after 7 and 14 days of force application, and 10 rats in each group were killed and sampled after 7 and 14 days of force application. The OTM distance was measured by stereomicroscope, the root morphology of the pressure side was observed by scanning electron microscope and the root resorption area ratio was measured. The root resorption and periodontal tissue remodeling of the pressure side were observed by HE staining and the root resorption index was calculated. The number of cementoclast and osteoclast in the periodontal tissue on the pressure side was counted by tartrate resistant acid phosphatase staining. RESULTS: The TOM distance of both groups increased with the extension of the force application time, and there was no significant difference ( P<0.05). There was no significant difference in OTM distance between the experimental group and the control group after 7 and 14 days of force application ( P>0.05). Scanning electron microscope observation showed that small and shallow scattered resorption lacunae were observed on the root surface of the experimental group and the control group after 7 days of force application, and there was no significant difference in the root resorption area ratio between the two groups ( P>0.05); after 14 days of application, the root resorption lacunae deepened and became larger in both groups, and the root resorption area ratio in the experimental group was significantly lower than that in the control group ( P<0.05). The range and depth of root absorption in the experimental group were smaller and shallower than those in the control group, and the root absorption index in the experimental group was significantly lower than that in the control group after 14 days of force application ( P<0.05). The number of cementoclast in the experimental group was significantly lower than that in the control group after 7 and 14 days of force application ( P<0.05); the number of osteoclasts in the experimental group was significantly lower than that in the control group after 14 days of force application ( P<0.05). CONCLUSION Local transplantation of hADSCs may reduce the area and depth of root resorption by reducing the number of cementoclasts and osteoclasts during OTM in rats, thereby inhibiting orthodontic-derived root resorption.
Rats ; Male ; Humans ; Animals ; Root Resorption/therapy* ; Rats, Sprague-Dawley ; Osteoclasts ; Tooth Movement Techniques ; Stem Cells

Objective To study von Willebrand factor(VWF) damage based on a novel Maglev Taylor-Couette blood-shearing device. Methods The magnetic levitation (maglev) Taylor-Couette blood-shearing device was designed, and the blood-shearing platform was built. Fresh porcine blood was tested in circulation loop for 1 hour at laminar flow state. VWF damage was assessed by analyzing sample through Western blot and enzyme-linked immunosorbent assay. Results With the increase of exposure time and shear stress, a large number of high molecular weight VWF multimers were degraded into low molecular weight VWF. The maximum rate of degradation was 569%. When the shear stress increased from 18 Pa to 55 Pa, the ratio of VWF-Rco to VWF-Ag decreased from 45.7% to 32.8%. ConclusionsCompared with initial sample, the VWF damage was mainly manifested by the decrease of high molecular weight VWF and the decrease of VWF activity, and VWF-Ag did not change significantly. The novel maglev Taylor-Couette blood-shearing device can quantitatively control the flow parameters (exposure time and shear stress), and be used for blood damage research in vitro, thus providing references for the design and optimization of extracorporeal membrane oxygenation and blood pump.

【Objective】 To explore the difference of total protein (TP) content, coagulation factor VIII (FⅧ) activity and Fib content in different common plasma products, and to further provide basis for the establishment and refinement of relevant quality standards of common plasma products. 【Methods】 Samples involved in the experiment included frozen plasma and cryoprecipitated frozen plasma derived from whole blood and eukocyte-depleted whole blood. The TP content determination was carried out by biuret method. The FⅧ activity (FⅧ: C) and Fib content were determined by coagulation method. 【Results】 The TP content( g/L) in frozen plasma and cryoprecipitated frozen plasma derived from whole blood and eukocyte-depleted whole blood were 59.64±4.78 vs 58.09±4.1 vs 52.20±3.57 vs 51.89±1.50, respectively, and the FⅧ: C( %) were 109.63±43.38 vs 27.06±7.09 vs 71.83±21.64 vs 21.66±3.86,, and the Fib content (g/L) were 2.19±0.39 vs 1.30±0.24 vs 2.04±0.37 vs1.22±0.15, respectively. There was a significant difference in TP content between other common plasma products (P<0.05) while similar between frozen plasma and cryoprecipitated frozen plasma derived from eukocyte-depleted whole blood (P>0.05). There was significant difference in FⅧ: C among four common plasma products (P<0.05). The Fib content of cryoprecipitated frozen plasma was significantly lower than that of frozen blood, and there was no significant difference in Fib content among other common plasma products (P>0.05). 【Conclusion】 The TP content and FⅧ: C of common plasma products are closely related to the initial blood and preparation process. It is suggested that the quality standard of common plasma products should be further refined, and the establishment of cryoprecipitated frozen plasma relevant quality standard and clinical indications should be considered.