[A Predictive Model for Hemoglobin Change before and after Collection of Apheresis Autologous Red Blood Cells in Patients].

OBJECTIVE: To analyze the affecting factors of hemoglobin changes in apheresis red blood cells (RBCs), and to establish a predictive model for the evaluation of apheresis. METHODS: The clinical data of 130 patients undergoing selective surgery for apheresis autologous RBCs from January 2017 to December 2018 were collected. The change of hemoglobin and its affecting factors before and after apheresis were analyzed. The predictive model of the hemoglobin change was established by machine learning algorithm and compared with the theoretical predictive model. RESULTS: The average Hb level in the 300 ml autologous RBC group decreased by 22.61±8.85 g/L, and the average Hb in 400 ml group decreased by 29.08±7.25 g/L. The change of Hb was mainly affected by Hb level before apheresis and peripheral circulation blood volume (P＜0.05). Sex, age, and the interval time between blood collection and operation not significantly influenced Hb change (P＞0.05). The initially established predictive model by the machine learning (MAE 6.27) is superior to the theoretical predictive model (MAE 8.11). CONCLUSION: The predictive model established by the machine learning can provide a reference for more accurate evaluation of apheresis autologous red blood cells.

[Factors Influencing Mononuclear Cell Collection in Tumor Cell Biotherapy].

OBJECTIVE: To investigate the factors affecting counting and collection efficiency of the final product- mononuclear cells (MNCs) in the collection of mononuclear cells for tumor cell biotherapy. METHODS: The collected data of 142 tumor patients and healthy donors were analyzed, including age, sex, height, weight, BMI, the total blood volume, diagnostic category, vascular access, operator, final product volume, ACD anticoagulant usage, flow rate and circulation times, pre-apheresis Hb, RBC, Plt, WBC, lymphocyte count, monocyte count, neutrophil count, circulating blood volume without anticoagulant, final product MNC and collection efficiency of MNC. CE(collection efficiency)%= final product MNC×100/(pre-apheresis MNC×circulating blood volume without anticoagulant). The factors affecting final products MNC and CE of MNC were detected by T test and multiple linear regression analysis. RESULTS: The CE of tumor patients was higher than that of healthy donors （24.41±1.91,vs 20.01±0.99)，(P=0.043）, and CE of MNC was different among different operators (P=0.01, H=18.59). There was a positive correlation of the final MNC with the volume of final product, ACD anticoagulant usage and pre-apheresis lymphocyte count (P= 0.00, P= 0.01, P= 0.00， r=0.811); CE of MNC negatively correlated with flow rate and pre-apheresis RBC, but positively correlated with operator's working age and ACD anticoagulant usage (P=0.01, P=0.04, P=0.03, P= 0.00, r=0.495). CONCLUSION: more higher pre-apheresis lymphocyte , more amount of the final product and ACD anticoagulant usage, and more high the final MNC. During the collecting process, more ACD anticoagulant usage and more high operator's seniority, lead to the higher MNC'S CE; while more high pre-apheresis RBC and more fast flow rate, cause the lower the CE of MNC.

[Study of biological characteristics of the IVpi-189 virus derived from persistent influenza A virus-infected cell line].

To investigate biological characteristics of the IVpi-189 progeny virus derived from the culture of influenza A virus as a live-attenuated vaccine candidate. Persistent infection of a cultured cell line with influenza A virus (MDCK-IVpi) was established by incubating continuously influenza virus-infected cells at a lower temperature. The infectious progeny virus derived from MDCK-IVpi cells at the 189rd subculture was designated as the IVpi-189 strain of influenza virus. The cytopathic effect induced by IVpi-189 virus was observed under different temperature conditions. The production of infectious progeny virus was examined at 38 and 32 degrees C by plaque titration of cell-associated and released virus. IVpi-189 virus showed cytopathic effect as strong as that of IVwt in infected cell line of MDCK at 32 degrees C. However, when culture temperature was raised to 38 degrees C, the cytopathic effect induced by IVpi-189 virus was delayed and less pronounced. Virus growth in IVpi-189 virus-infected cells at 38 degrees C was significantly reduced as compared with that of IVwt virus, although both viruses yielded nearly equivalent high titers of cell-associated and released virus at 32 degrees C. The reasons of the decreased proliferative ability of IVpi-189 virus at high culture temperature were unrelated with virus inactivation or the release of progeny virus, but associated with the decreased replication of infectious progeny virus in the infected cells. IVpi-189 virus derived from MDCK cells infected persistently with influenza A virus showed biological characteristics as a potential live-attenuated vaccine candidate.

Evaluation of models of the mechanisms underlying intron loss and gain in Aspergillus fungi.

Although intron loss and gain have been widely observed, their mechanisms are still to be determined. In four Aspergillus genomes, we found 204 cases of intron loss and 84 cases of intron gain. Using this data, we tested common hypotheses of intron loss or gain. Statistical analysis showed that adjacent introns tend to be lost simultaneously and small introns were preferentially lost, supporting the model of mRNA-mediated intron loss. The lost introns reside in internal regions of genes, which is inconsistent with the traditional version of the model (partial length cDNAs are reverse transcribed from 3' ends of mRNAs), but consistent with an alternate version (partial length cDNAs are produced by self-primed reverse transcription). The latter version was not supported by examination of the abundance of T-rich segments in mRNAs. Preferential loss of internal introns might be explained by highly efficient recombination at internal regions of genes. Among the 84 cases of intron gain, we found a significantly higher frequency of short direct repeats near exon-intron boundary than in conserved introns, supporting the double-strand break repair model. We also found possible source sequences for two cases of intron gain, one by gene conversion and one by insertion of a mitochondrial sequence during double-strand break repair. Source sequences for most gained introns could not be identified and the possible reasons were discussed. In the four Aspergillus genomes studied, we did not find evidence of frequent parallel intron gains.

[Comparison of the effects resulted by modified maxillary oblique plate and Twin-block in advancing mandible].

UNLABELLED: URPOSE: The aim of this study was to evaluate the effects resulted by modified maxillary oblique plate in advancing mandible. METHODS: Twelve Class II division II cases (4 males, 8 females) with mandibular retrusion were selected as group 1 aligned by fixed appliances in the upper arches, and their mandibles were advanced by the modified maxillary oblique plates. Meanwhile, twelve Class II division II cases (5 males, 7 females) with mandibular retrusion were selected as group 2 treated with the Twin-block. The average age was 11 years 8 months in group 1, and 11 years 6 months in group 2. The effects of advancing mandible were compared between the two groups by analyzing cephalometric films before and after treatment with SAS6.0 software package. RESULTS: Mandibular advancement was achieved in the two groups. Mandibular anterior teeth labial tipping was more obvious in group 1 than in group 2, but without significant those(P>0.05). Both mesial and occlusal movements of the lower first molar in group 2 were more significant than those in group 1 (P<0.05). CONCLUSIONS: Based on the results, the modified maxillary oblique plate is an excellent appliance for the advancing mandible in Class II division II cases with the advantages of economics, simplification and effectiveness.