Objective:To investigate the application effect of the teaching model of massive open online course (MOOC)+small private online course (SPOC) in the undergraduate clinical teaching of Fundamentals of Surgery.Methods:A total of 30 undergraduate medical trainees in the five-year program were randomly divided into experimental group and control group, with 15 trainees in each group. With the chapter of basic surgical procedures as an example, the trainees in the control group received traditional teaching, and those in the experimental group received MOOC+SPOC teaching. Theoretical assessment and surgery simulation were performed at one week after the course to evaluate the teaching effect. SPSS 17.0 was used for the t-test and the chi-square test. Results:The experimental group had a theoretical assessment score of (92.5±6.4) points and a basic skill operation score of (91.7±2.2) points, while the control group had a theoretical assessment score of (85.3±7.3) points and a basic skill operation score of (83.6±6.4) points. The experimental group had an excellent rate of 60% (9/15) in theoretical assessment and 66.7% (10/15) in basic skill operation test, while the control group had an excellent rate of 40% (6/15) in theoretical assessment and 33.3% (5/15) in basic skill operation test. The experimental group had significantly higher scores and grades than the control group ( P<0.05). Conclusion:MOOC+SPOC teaching can significantly enhance the understanding of theoretical knowledge and the mastery of operational skills among trainees and improve teaching effect, and therefore, it has a good application prospect.

Objective:A rare case of δ-globin gene (HBD) mutation in Guangdong Province was analyzed to provide reference for avoiding misdiagnosis of δ-thalassemia in clinic.Methods:The patient was admitted to Guangdong Maternal and Child Health Hospital, and the peripheral blood sample was collected for hematological phenotypes [mean erythrocyte volume (MCV), mean erythrocyte hemoglobin content (MCH), hemoglobin (Hb)] and Hb typing analysis. The routine deletion and mutation of α-thalassemia and β-thalassemia genes were analyzed by PCR-flow fluorescence hybridization. At the same time, DNA sequencing was used to analyze the type of HBD mutation.Results:The results of hematological phenotypes analysis showed that MCV was 87.9 fl, MCH was 29.3 pg, and Hb content was 140 g/L. The results of Hb typing showed that the contents of Hb F, Hb A 2, Hb A 2 variant, and Hb A were 0.4%, 1.3%, 0.6%, and 97.7%, respectively. No abnormality was found in α-thalassemia and β-thalassemia genes by routine deletion and mutation detection. According to DNA sequencing analysis, the patient had HBD: c.349 C>G variant. Conclusion:The low Hb A 2 content (reference value is 2.5% - 3.5%) in this case is due to the mutation of HBD, HBD: c.349 C>G variant is rare in Chinese population.

The quality inspection of magnetic resonance imaging (MRI) performance parameters is an important means to ensure the image quality and the reliability of diagnosis results. There are some problems in the manual calculation and eye recognition of the quality inspection parameters, such as strong subjectivity and low efficiency. In view of these facts, an automatic analysis system for MRI quality detection based on QT is proposed and implemented in C++ language. The image processing algorithm is introduced to automatically measure and calculate the quality inspection parameters. The software with comprehensive functions is designed to systematically manage the quality inspection information of MRI. The experimental results show that the automatically calculated parameters are consistent with the manually calculated ones. Accordingly, the accuracy and reliability of the algorithm is verified. The whole system is efficient, convenient and easy to operate, and it can meet the actual needs of MRI quality inspection.
Algorithms ; Image Processing, Computer-Assisted ; Magnetic Resonance Imaging ; standards ; Reproducibility of Results

Objective To establish and optimize a loop-mediated isothermal amplification (LAMP) method for the rapid detection of Escherichia coli and its microbial toxin.Methods The LAMP reaction system and reaction conditions were determined by optimizing LAMP reaction,and the optimized LAMP system was used for the detection.Results Primers targeting shiga toxin (stx) gene and O157 antigen gene rfbe were designed.The established and optimized LAMP amplification system contained 1.2 mmol/L dNTPs,10 mmol/L MgSO4,0.4 mol/L betaine,1 μl 10 × Bst DNA polymerase Buffer,8 U Bst DNA polymerase fragment,2 μl DNA template,and the ratio of inner-primer (FIP and BIP) and outerprimer (F3 and B3) were 8∶ 1.Time and temperature for LAMP was 60 min,60 ℃.The sensitivity was 103 times higher than polymerase chain reaction (PCR),reached 5 × 101 CFU/ml.When LAMP was applied to 19 reference strains,102 EHEC strains,the specification was 100％ while identification rate of rfbe,stx1 and stx2 gene reached 100％,95.2％,92.9％.Conclusions The LAMP method showed a promising prospect for the rapid detection of common nosocomial pathogens microbial toxin.

Objective To explore the cytotoxic effects and mechanisms of Aflatoxins B1(AFB1) on the African green monkey kidney cells (Vero E6).Methods After incubation of Vero E6 cells with AFB1,cellular toxicity was assessed by CCK-8 assay and LDH release rate.Annexin V/PI double staining and DAPI staining was used to detected cell apoptosis.Results AFB1 has significant toxic effects on Vero E6 cells.Cell viability was less than 10% when treated by 200 μmol/L AFB1 for 48 h.LDH release rate was increased significantly with the increase of AFB1 concentration.Externalization of cell membrane phosphatidylserine was observed by Annexin V/PI double staining.Nucleus fragmentation was detected by DAPI staining.Conclusion AFB1 exhibits significantly cytotoxic effects on Vero E6 cells by inducing cell apoptosis.

The patient was a 21 days-old baby girl,admitted to Guangdong Women and Children Hospital because of "poor intake,seldom crying and no activity in 1 day".The major clinical manifestations included hypotonia,aggravation of the conscious disturbance,pancytopenia,intractable acidosis and hyperammonemia,so,inherited metabolic disorders should be considered.Screening of inherited metabolic diseases with blood and urine samples,genetic test and active treatments were carried out.After targeted next-generation sequencing,a novel homozygotic frame shift mutation in PCCB gene:c.838_839insC (L280Pfs * 11) was identified,which was validated by Sanger sequencing.This mutation had not been reported in the mutation database,and bioinformatic analysis of this mutation indicated disease-causing.So,the diagnosis of propionic acidemia was identified.The baby was in a critical condition,and despite active treatment,her conscious disturbance was aggravated,and the spontaneous breathing disappeared.Subsequently,the baby died of pneumonia.Propionic acidemia is a relatively common genetic metabolic disease in newborns.The severity and the clinical phenotypes of propionic acidemia varied,which often made the diagnosis difficult.When the baby is presented with developmental delay,hypotonia,recurrent convulsion and vomiting,etc,which can't be explained by common diseases of children,propionic acidemia may be considered.Next generation sequencing analysis of the complicated cases can easily to pinpoint a disease-causing gene,which lays a solid foundation for accurate diagnosis and treatment of the patients.

Objective To investigate the application value of fetal umbilical cord blood hemoglobin analysis in the prenatal diag ‐nosis of thalassemia .Methods 113 couples were the carriers of the same gene type of thalassemia ,moreover the females were in the pregnant period of 24 - 30 pregnant weeks and performed the prenatal diagnosis .The fetal umbilical cord blood hemoglobin compo‐nents were analyzed by the full automatic capillary electrophoresis technique ,meanwhile the fetal thalassemia gene was detected .Re‐sults Among 113 fetuses ,the umbilical cord blood HbBart′s level in 11 cases of severe α thalassemia was 85 .0% - 95 .5% ,which in 9 cases of intermediate type α thalassemia was 22 .0% - 39 .5% ;the umbilical cord blood HbA level in 6 cases of severe β thalas‐semia was 0% - 0 .4% ,which in 17 cases of light type β thalassemia was 2 .1% - 12 .5% .Conclusion The fetal umbilical cord blood hemoglobin analysis could be used for rapid prenatal diagnosis of severe α ,β and intermediate type α thalassemia ,which can serve as a supplementary method for the prenatal diagnosis of thalassemia .

Objective To compare the effect of three β-thalassemia prenatal screening strategies in Guangdong province. Methods A total of 13 284 hospital-delivered couples and 13 369 newborns were recruited from 91 hospitals in 21 counties or districts of Guangdong province from June to December 2012. Mean cell volume (MCV), mean corpuscular hemoglobin (MCH) and hemoglobin A2 (Hb A2) were tested for all the couples, and all the couples and newborns were detected by 17 types ofβ-globin gene mutations. The effect of three β-thalassemia prenatal screening strategies were compared as following:(1) MCV/MCH with Hb A2 serial screening(SS):Hb A2 was tested if the woman′s MCV<82 fl and(or)MCH<27 pg. If the woman′s Hb A2>3.5, it meant positive. And if the woman wasβ-thalassemia carrier and her husband′s Hb A2>3.5, it meant couple positive. (2) MCV/MCH with Hb A2 parallel screening(PS):if the woman′s MCV<82 fl and (or) MCH<27 pg and(or) Hb A2>3.5 pg, it meant couple positive. And the husband would be tested forβ-globin gene mutations if the woman was β-thalassemia carrier. (3) MCV/MCH with Hb A2 serial screening for couples(SSC):if one of the couple or both of them had MCV<82 fl and(or) MCH<27 pg, the couple would be tested for Hb A2, and if one of the couple got Hb A2>3.5, it meant couple positive. Results (1) For the SS strategy, the sensitivity was 92.69%(583/629);the specificity was 99.87%(12 638/12 655); the positive predictive value was 97.17%(583/600);and the negative predictive value was 99.64%(12 638/12 684). The results ofβ-globin gene mutations tested showed that the rate ofβ-thalassemia carriers was 4.74%(629/13 284) in the 13 284 pregnant women, and it was 4.29%(570/13 284) in their husbands. (2) The SS strategy detected 27 (0.20%,27/13 284) β-thalassemia carrier couples. For the SS strategy detecting β-thalassemia carrier couples, the missed diagnosis rate was 11.11%(3/27);the sensitivity was 88.89%(24/27);the specificity was 100.00%(27/27); the positive predictive value was 100.00%(24/24); and the negative predictive value was 99.98%(13 257/13 260). (3) When using the SS strategy for 13 369 offsprings, there were 582β-thalassemia carriers (4.35%,582/13 369), including 578 (99.31%,578/582) minorβ-thalassemia, 3 (0.52%,3/582) intermediaβ-thalassemia and 1 (0.17%,1/582) major β-thalassemia. The SS strategy detected 25 fetuses who neededβ-thalassemia prenatal diagnosis. (4) For the PS strategy, the sensitivity was 98.09%(617/629); the specificity was 88.73%(11 229/12 655); the positive predictive value was 30.20%(617/2 043); and the negative predictive value was 99.89%(11 229/11 241). (5) When using the PS strategy for theβ-thalassemia carrier couples, the sensitivity was 100.00%(27/27);the specificity was 95.55%(12 667/13 257);the positive predictive value was 4.38%(27/617);and the negative predictive value was 100.0%(12 667/12 667). (6) The PS strategy detected 28 fetuses who needed β-thalassemia prenatal diagnosis in 13 369 offsprings. (7) For the SSC strategy, the sensitivity was 93.80%(590/629); the specificity was 95.75%(12 117/12 655); the positive predictive value was 52.30%(590/1 128); and the negative predictive value was 99.68%(12 117/12 156). When the SSC strategy was used for the husbands, the sensitivity was 92.28%(526/570); the specificity was 95.27%(12 112/12 714);the positive predictive value was 46.63%(526/1 128); and the negative predictive value was 99.64%(12 112/12 156). (8) When the SSC strategy was used inβ-thalassemia carrier couples, the sensitivity was 100.00%(27/27);the specificity was 91.69%(12 156/13 257);the positive predictive value was 2.39%(27/1 128);and the negative predictive value was 100.00%(12 156/12 156). (9) The SSC strategy detected 28 fetuses who neededβ-thalassemia prenatal diagnosis. Conclusions All the three β-thalassemia prenatal screening strategies had good effect in clinical practice and public health. While in the high-prone area of β-thalassemia, MCV/MCH with Hb A2 parallel screening and MCV/MCH with Hb A2 serial screening for couples stratigies were better.

Female ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis ; alpha-Globins ; genetics

Objective To compare the effect and cost of three different α-thalassemia prenatal screening strategies used in Guangdong, China, and to provide evidence for α-thalassemia prevention. Methods In total, 13 284 hospital-delivery couples and 13 369 newborns/fetuses (offspring) from 21 counties or districts of Guangdong Province were included in this study, who were treated from June to December 2012. Mean cell volume (MCV), mean corpuscular hemoglobin (MCH) and hemoglobin A2 (Hb A2) were detected in the couples, and 6 types ofα-globin gene mutations were found in all couples and newborns. The strategies were MCV/MCH and serum Hb A2 (protocolⅠ) or parallel screening based on pregnant women (protocolⅡ), and serum screening based on couples (protocolⅢ). The validity and reliability of the three strategies were then compared using the Chi-square test. Results The sensitivity and the specificity of pregnant women who wereα-thalassemia carriers in protocolⅠwere 74.82%(1 352/1 807) and 74.11%(8 506/11 477), and were 89.82%(1 623/1 807) and 48.60%(5 578/11 477) in protocol Ⅱ , respectively. And 1.67% (221/13 284) couples were bothα-thalassemia carriers by the gene test. The rate of missed diagnosis in bothα-thalassemia carrier couples in protocolsⅠ,ⅡandⅢwas 50.68%(112/221), 11.76%(26/221) and 11.31%(25/221), respectively. In couples who needed prenatal diagnosis, the rates of missed diagnosis, sensitivity, specificity, positive predictive value, and negative predictive value were 17.46%(11/63), 82.54%(52/63),98.35%(13 003/13 221), 19.26%(52/270) and 99.92%(13 003/13 014) in protocolⅠ;4.76%(3/63), 95.24%(60/63), 88.18%(11 658/13 221), 3.70%(60/1 623) and 99.97%(11 658/11 661) in protocolⅡ;and 3.17%(2/63), 96.83%(61/63), 59.31%(7 842/13 221), 1.12%(61/5 440) and 99.97%(7 842/7 844) in protocol Ⅲ , respectively. The diagnosis of severeα-thalassemia was not missed in all three screening strategies. The mean cost of protocols Ⅰ, Ⅱ and Ⅲ for detecting a couple who needed prenatal diagnosis was 37 049.23, 50 836.00 and 40 321.64 RMB, respectively. Conclusions The three screening protocols have good efficiency in screening forα-thalassemia. However, protocolsⅡandⅢare preferred when financial conditions permit.