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Phillip S. Naimo Tyson A. Fricke Melissa G.Y. Lee Yves d'Udekem Johann Brink Christian P. Brizard Igor E. Konstantinov 《The Journal of thoracic and cardiovascular surgery》2021,161(2):368-375
ObjectiveTo determine the outcomes of patients with a quadricuspid truncal valve (TV) and durability of TV repair.MethodWe reviewed 56 patients with truncus arteriosus and a quadricuspid TV who underwent complete repair between 1979 and 2018.ResultsTV insufficiency was present in 39 patients (mild, n = 22; moderate, n = 14; and severe, n = 3). Fourteen patients had concomitant TV surgery. Early mortality in patients who had concomitant TV surgery was 14% (2 out of 14 patients) and overall survival was 77.1% ± 11.7% at 15 years. Freedom from TV reoperation was 30.3% ± 14.6% at 15 years. Early mortality in patients who did not undergo concomitant TV surgery was 9.5% (4 out of 42 patients) and overall survival was 74.9% ± 6.9% at 15 years. Progression of TV insufficiency requiring TV surgery occurred in 16.7% (7 out of 42 patients). Freedom from TV reoperation was 77.1% ± 7.8% at 15 years. The most common method of repair was tricuspidization of the TV. Freedom from TV reoperation was 64.3% ± 21.0% at 10 years after tricuspidization and 0% at 6 years after other types of TV surgery. Overall follow-up was 97.6% (41 out of 42 patients) complete for survivors with median follow-up of 16.6 years. At last follow-up there was no TV insufficiency in 16 patients, mild insufficiency in 24 patients, and moderate insufficiency in 1 patient.ConclusionsMore than one-third of patients with a quadricuspid TV require TV surgery. Tricuspidization of the quadricuspid TV appears to be a durable repair option with good long-term outcomes. 相似文献
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The kinesin superfamily of proteins (KIFs) are microtubule motor proteins that use the hydrolysis of ATP to power directional movement along microtubules. KIFs induce microtubule depolymerization to regulate the length and dynamics of microtubules in a variety of cell processes and structures, including the mitotic and meiotic spindles and centriole and interphase microtubules. KIF plays a significant role in the transport of organelles, protein complexes and mRNAs. The brown planthopper (Nilaparvata lugens) is a major insect pest in rice paddy fields. Ovarian development is regulated by multiple factors, including endocrine factors. The role of KIFs in brown planthopper ovarian development remains unknown. We found that downregulation of KIF2A significantly compromised the development and eclosion of the brown planthopper, delayed ovarian cell cycle progression, disrupted ovarian development, reduced the expression of MCM genes required for DNA replication and significantly reduced the number of nuclei in the follicles. We also found a significant reduction in Vg mRNA and protein levels. We conclude that downregulation of KIF2A disrupts the cell cycle progression of cells. Alternatively, the ovarian phenotype could be an indirect effect of a compromised trophic cord. In summary, KIF2A regulates ovarian development via modulating cell cycle progression and/or vitollogenin transportation. 相似文献
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H. Jang Y.-J. Ma E.Y. Chang S. Fazeli R.R. Lee A.F. Lombardi G.M. Bydder J. Corey-Bloom J. Du 《AJNR. American journal of neuroradiology》2021,42(5):868
BACKGROUND AND PURPOSE:MR imaging has been widely used for the noninvasive evaluation of MS. Although clinical MR imaging sequences are highly effective in showing focal macroscopic tissue abnormalities in the brains of patients with MS, they are not specific to myelin and correlate poorly with disability. We investigated direct imaging of myelin using a 2D adiabatic inversion recovery ultrashort TE sequence to determine its value in assessing disability in MS.MATERIALS AND METHODS:The 2D inversion recovery ultrashort TE sequence was evaluated in 14 healthy volunteers and 31 patients with MS. MPRAGE and T2-FLAIR images were acquired for comparison. Advanced Normalization Tools were used to correlate inversion recovery ultrashort TE, MPRAGE, and T2-FLAIR images with disability assessed by the Expanded Disability Status Scale.RESULTS:Weak correlations were observed between normal-appearing white matter volume (R = –0.03, P = .88), lesion load (R = 0.22, P = .24), and age (R = 0.14, P = .44), and disability. The MPRAGE signal in normal-appearing white matter showed a weak correlation with age (R = –0.10, P = .49) and disability (R = –0.19, P = .31). The T2-FLAIR signal in normal-appearing white matter showed a weak correlation with age (R = 0.01, P = .93) and disability (R = 0.13, P = .49). The inversion recovery ultrashort TE signal was significantly negatively correlated with age (R = –0.38, P = .009) and disability (R = –0.44; P = .01).CONCLUSIONS:Direct imaging of myelin correlates with disability in patients with MS better than indirect imaging of long-T2 water in WM using conventional clinical sequences.MS is the most common demyelinating disease of the brain.1 Demyelination affects many aspects of neurologic function, including speech, balance, and cognitive awareness. Across time, this frequently leads to severe and irreversible clinical disability. MR imaging has been widely used for accurate diagnosis of MS, with current techniques focused on imaging the long-T2 water components in WM and GM.2-4 MS lesions often appear hypointense with T1-weighted gradient recalled-echo sequences2 and hyperintense with T2-weighted FSE and T2-weighted FLAIR sequences.3 Active lesions can be highlighted with gadolinium-enhanced imaging.4 The magnetization transfer ratio has been used as an indirect marker of myelin disorder in regions of normal-appearing WM (NAWM).5 There are also several other advanced imaging techniques for indirect myelin imaging via assessment of myelin water, such as multicomponent T2 or T2* analysis6,7 and direct visualization of components with short transverse relaxation times.8,9While conventional MR imaging sequences are highly effective in detecting focal macroscopic brain tissue abnormalities, they are not specific for pathologic substrates of MS lesions such as demyelination and remyelination, and they may not correlate well with patients'' neurologic deficits. Current MR imaging techniques correlate only modestly with disability assessed by the Expanded Disability Status Scale (EDSS).10-15 The total lesion load showed statistically significant-but-weak correlations with the EDSS score in several large-scale studies (R = 0.1–0.3).10-12 Composite scores including relaxation times of different tissues and/or volumetric measures generally correlate more strongly with the EDSS score, with a maximum observed correlation of R = 0.34 (P < .001).13 Lesions seen with gadolinium-enhanced imaging are only moderately correlated with disability in the first 6 months and are not predictive of changes in the EDSS score in the subsequent 1 or 2 years.14 A large-scale multicenter study reported very limited correlation between the EDSS score and normalized brain volume (R = –0.18), cross-sectional area (R = –0.26), magnetization transfer ratio of whole-brain tissue (R = –0.16), and GM (R = –0.17).15The poor performance of conventional MR imaging sequences in assessing disability highlights the need for novel MR imaging techniques that can directly image myelin lipid and enable direct assessment of both myelin damage and repair. However, myelin has an extremely short transverse relaxation time and is not directly detectable with conventional MR images, which typically have TEs of several milliseconds or longer. Ultrashort TE (UTE) sequences can directly detect signal from myelin with ultrashort T2 (ie, excluding water with longer T2s).16-21 In this study, we describe imaging of WM using a 2D adiabatic inversion recovery prepared UTE (IR-UTE) sequence in healthy volunteers and patients with MS and evaluate its performance in assessing disability in patients with MS compared with 2 conventional clinical sequences. 相似文献
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