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711.
Our aim was to compare white matter (WM) microstructure in preterm infants with and without punctate WM lesions on MRI using tract-based spatial statistics (TBSS) and probabilistic tractography. We studied 23 preterm infants with punctate lesions, median GA at birth 30 (25-35) wk, and 23 GA- and sex-matched preterm controls. TBSS and tractography were performed to assess differences in fractional anisotropy (FA) between the two groups at term equivalent age. The impact of lesion load was assessed by performing linear regression analysis of the number of lesions on term MRI versus FA in the corticospinal tracts in the punctate lesions group. FA values were significantly lower in the posterior limb of the internal capsule, cerebral peduncles, decussation of the superior cerebellar peduncles, superior cerebellar peduncles, and pontine crossing tract in the punctate lesions group. There was a significant negative correlation between lesion load at term and FA in the corticospinal tracts (p = 0.03, adjusted r2 = 0.467). In conclusion, punctate lesions are associated with altered microstructure in the WM fibers of the corticospinal tract at term equivalent age.  相似文献   
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Preterm birth affects 5–18% of all babies and is associated with neurodevelopmental impairment and increased neuropsychiatric disease risk. Although preterm birth associates with differential DNA methylation at neurodevelopmental genes in buccal DNA, including leucine‐rich alpha‐2‐glycoprotein 1 (LRG1), it is not known whether these differences also occur in the brain, or whether they persist. Thus, there is a need for animal models or in vitro systems in which to undertake longitudinal and mechanistic studies. We used a combination of in vivo rat studies and ex vivo experiments in rat cortical slices to explore their utility in modelling the human preterm brain. We identified temporal changes in DNA methylation at LRG1 in human buccal DNA over the first year of life and found persistent differences in LRG1 methylation between preterm and term infants at 1 year. These developmental changes also occurred in rat brains in vivo, alongside changes in global DNA hydroxymethylation and expression of the ten‐eleven translocation (Tet1) enzyme, and were reproducible in ex vivo rat cortical slices. On the basis of the observation that neonatal glucose homeostasis can modify neurodevelopmental outcome, we studied whether glucose concentration affects Lrg1 methylation using cortical slices. Culture of slices in lower glucose concentration was associated with lower Lrg1 methylation, lower global 5hmC and Tet1 expression. Our results suggest that ex vivo organotypic cultures may be useful in the study of biological and environmental influences on the epigenome and that perturbations during early life including glucose concentration can affect methylation at specific genes implicated in neurodevelopment.  相似文献   
714.
The use of splints and casts in the treatment of war injuries varied according to the particular echelon of command in which they were required. In general, emergency splinting was effected with the regulation army halfring splint. For transportation following primary surgery plaster was almost universally employed. Definitive splinting in the Zone of Communication was accomplished by use of the halfring splint or plaster, frequently by a combination of the two. Internal splinting was, for the most part, reserved for the Zone of the Interior. Two points deserve especial attention; the use of splints in the protection of extensive soft tissue injuries during transportation and the abuse of splints in the treatment of fractures of the hand.  相似文献   
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716.

Aim

This study was performed to evaluate concordance between clinical and pathologic staging of non-small cell lung cancer (NSCLC) in our hospital network.

Methods

We retrospectively reviewed records of 417 patients with NSCLC who received curative surgery and whose pathology was evaluated in our hospital between 2016 and 2021. Cytology, tissue pathology, and associated clinical, surgical, and imaging information were retrieved from hospital digital records.

Results

The cohort included 214 female and 203 male patients aged 20.6–85.8 years. Median times among staging computed tomography and surgery (105 days [interquartile range (IQR) 77.0–143.0]), positron emission tomography and surgery (78.5 days [IQR 56.0–109.0]), and endobronchial ultrasound-guided transbronchial needle aspiration and surgery (59 days [IQR 42–94]) indicated that Australian guidelines of <42 days between original referral and commencement of treatment were not being met in the majority of cases. Discordance between clinical TNM (cTNM) and pathologic TNM staging was 25.9%, including 18.4% cases that were clinically understaged and two patients with undetected stage IVA disease. cTNM understaging was significantly associated with time between the final staging investigation and surgery (p = .023), pleural (p < .05) and vessel (p < .05) invasion, and diagnosis of high-grade adenocarcinoma (p = .001).

Conclusion

Discordance between clinical and pathologic staging of NSCLC is associated with tumor histopathologic characteristics and treatment delays. Although tumor factors that lead to discordant staging cannot be controlled, reduced time to surgery may have resulted in better outcomes for some patients in this potentially curable lung cancer cohort.  相似文献   
717.
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