ABSTRACT
Objective To investigate MR T2-mapping in evaluating birth-related levator ani muscle injury.Methods 25 primiparas at 6 weeks after first vaginal delivery as primiparous group and 12 nulliparous volunteers as control group were prospectively studied. All the subjects underwent pelvic MRI including T2-mapping,mDIXON-T2 WI sequences.Levator ani muscle were divided into two subgroups:levator ani muscle injury group and non-injury group according to if there were edema,avulsion,or rupture in each levator ani muscle subdivisions[puborectal muscle(PRM);iliococcygeal muscle(ICM)],which were showed on mDIXON-T2 WI images.Two radiologists evaluated T2 values of PRM,ICM and observed artificial color images respectively.The consistency between two observers for T2 values of PRM,ICM were evaluated using the intraclass correlation coefficient (ICC ),the difference of T2 values in each levator ani muscle subdivisions among control group,non-injury group and muscle injury group were analyzed using ANOVA .Results There were 26 PRM injury cases and 24 non-injury cases in primiparous group on mDIXON-T2 WI images,and no ICM injured cases in our study.Inter-rater reliability for T2 values between two observers were good(ICC >0.75).T2 values in PRM injury group,non-injury group and control group were(62.78±1.23)ms,(49.75±3.17)ms,(49.96±4.37)ms respectively and the difference was significant. There were significant difference between PRM injury group and non-injury group,control group respectively(P =0.000,P =0.000). The T2 values of ICM in PRM injury group,non-injury group and control group were(70.80±6.50)ms,(62.41±7.32)ms,(62.78±6.91)ms and there were significant difference(P =0.000),meanwhile the difference between PRM injury group and non-injury group,control group were significant respectively(P =0.000,P =0.000).The color gradation of PRM in PRM injury group were mixed with blue, green,and yellow,and tone were lightened on T2-mapping artificial color images;ICM color gradation were uneven with green and yellow, a d tone were higher than those of control group and non-injurygroup.Conclusion T2-mapping can quantitatively assess birth-related levator ani muscle injury and T2-mapping artificial color images show the range and degree of levator ani muscle injury visually.It is hopeful to find micro lesions that T2 WI images are difficult to find.
ABSTRACT
Objective To investigate MR T2-mapping in evaluating birth-related levator ani muscle injury.Methods 25 primiparas at 6 weeks after first vaginal delivery as primiparous group and 12 nulliparous volunteers as control group were prospectively studied. All the subjects underwent pelvic MRI including T2-mapping,mDIXON-T2 WI sequences.Levator ani muscle were divided into two subgroups:levator ani muscle injury group and non-injury group according to if there were edema,avulsion,or rupture in each levator ani muscle subdivisions[puborectal muscle(PRM);iliococcygeal muscle(ICM)],which were showed on mDIXON-T2 WI images.Two radiologists evaluated T2 values of PRM,ICM and observed artificial color images respectively.The consistency between two observers for T2 values of PRM,ICM were evaluated using the intraclass correlation coefficient (ICC ),the difference of T2 values in each levator ani muscle subdivisions among control group,non-injury group and muscle injury group were analyzed using ANOVA .Results There were 26 PRM injury cases and 24 non-injury cases in primiparous group on mDIXON-T2 WI images,and no ICM injured cases in our study.Inter-rater reliability for T2 values between two observers were good(ICC >0.75).T2 values in PRM injury group,non-injury group and control group were(62.78±1.23)ms,(49.75±3.17)ms,(49.96±4.37)ms respectively and the difference was significant. There were significant difference between PRM injury group and non-injury group,control group respectively(P =0.000,P =0.000). The T2 values of ICM in PRM injury group,non-injury group and control group were(70.80±6.50)ms,(62.41±7.32)ms,(62.78±6.91)ms and there were significant difference(P =0.000),meanwhile the difference between PRM injury group and non-injury group,control group were significant respectively(P =0.000,P =0.000).The color gradation of PRM in PRM injury group were mixed with blue, green,and yellow,and tone were lightened on T2-mapping artificial color images;ICM color gradation were uneven with green and yellow, a d tone were higher than those of control group and non-injurygroup.Conclusion T2-mapping can quantitatively assess birth-related levator ani muscle injury and T2-mapping artificial color images show the range and degree of levator ani muscle injury visually.It is hopeful to find micro lesions that T2 WI images are difficult to find.
ABSTRACT
Objective To investigate the prompt value of abnormal vaginal morphology on diagnosing pelvic organ prolapse . Methods Forty eight pelvic organ prolapse female patients diagnosed by pelvic organ prolapse quantification were enrolled in the pelvic organ prolapse group and 51 normal female volunteers were enrolled in the control group in this study. Pelvic MRI T2WI were performed in all cases. The vaginal shape were evaluated according to Delancey Ⅱ level on the transverse images, which were divided into two categories:normal morphology (H-shaped) and abnormal morphology(non H-shaped). The vaginal shape distribution of different prolapse degree(0,Ⅰ,Ⅱ,Ⅲ,Ⅳstage) and types(anterior,middle, posterior pelvic prolapse) were recorded. Chi-square test was used to analyse distribution difference of vaginal shape between the two groups. The ROC curve was used to analyse the diagnostic efficiency of abnormal vaginal morphology for diagnosing pelvic organ prolapse. Results In the control group, there were 40 cases with normal vaginal morphology and 11 cases with abnormal morphology mainly including W-shaped and U-shaped abnormal morphology. In the prolapse group, there were 5 cases with normal vaginal morphology and 43 cases with abnormal morphologymainly including U-shaped (13 cases), W-shaped (26 cases) and O-shaped(4 cases) abnormal morphology. There was significant difference between the two groups(c2=46.137,P<0.01). The area under the curve (AUC) was 0.800. The sensitivity and specificity of abnormal vaginal shape for diagnosing pelvic organ prolapse were 89.6% and 78.4%respectively.The distribution of vaginal morphology in different degrees and types of prolapse were different:vaginal morphology of 0 stage prolapse showed H-typed mainly (40/51, 78.4%), Ⅰ stage prolapse showed W-shaped (16/28 57.1%), Ⅱ,Ⅲ stage prolapse all showed non H-shaped (20/20, 100%), Ⅱstage mainly showed W-shaped (9/14), Ⅲ stage mainly showed O-shaped (3/6). Anterior pelvic organ prolapse were manifested mainly with W-shaped vaginal morphology (4/9) and middle pelvic organ prolapse mainly showed O-shaped vaginal morphology (4/7). Conclusions The abnormal vaginal morphology has the prompt value on diagnosing pelvic organ prolapse.Moreover, the different shape probably indicates the different degrees and types of pelvic organ prolapse.
ABSTRACT
Malic acid is a dicarboxylic acid that is widely used in food, pharmaceutical and chemical industries. We studied the effects of overexpression of carboxylation pathway genes and inactivation of malic enzymes on the aerobic production of malic acid. Over expression of phosphoenolpyruvate (PEP) carboxylase (ppc) generated strain E21, which increased malic acid production from 0.57 g/L to 3.83 g/L. Then pyc gene from Coryenbacterium glutamicus and pck gene from Actinobacillus succinogenes were overexpressed in E21 separately. The resulting strains E21 (pTrcpyc) and E21 (pTrc-A-pck) produced 6.04 and 5.01 g/L malate with a yield of 0.79 and 0.65 mol/mol glucose, respectively. Deleting two malic enzymes (encoded by maeA and maeB) also led to an increase of 36% in malic acid production with a production of 5.21 g/L. However, the combination of malic enzymes deletion and pyc overexpression could not further increase the yield of malic acid. After optimization of fermentation conditions, strain E21 (pTrcpyc) produced 12.45 g/L malic acid with a yield of 0.84 mol/mol which is 63.2% of the theoretical yield.