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BACKGROUND AND PURPOSE:In the chronic phase after traumatic brain injury, DTI findings reflect WM integrity. DTI interpretation in the subacute phase is less straightforward. Microbleed evaluation with SWI is straightforward in both phases. We evaluated whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase.MATERIALS AND METHODS:Sixty of 211 consecutive patients 18 years of age or older admitted to our emergency department ≤24 hours after moderate to severe traumatic brain injury matched the selection criteria. Standardized 3T SWI, DTI, and T1WI were obtained 3 and 26 weeks after traumatic brain injury in 31 patients and 24 healthy volunteers. At baseline, microbleed concentrations were calculated. At follow-up, mean diffusivity (MD) was calculated in the normal-appearing WM in reference to the healthy volunteers (MDz). Through linear regression, we evaluated the relation between microbleed concentration and MDz in predefined structures.RESULTS:In the cerebral hemispheres, MDz at follow-up was independently associated with the microbleed concentration at baseline (left: B = 38.4 [95% CI 7.5–69.3], P = .017; right: B = 26.3 [95% CI 5.7–47.0], P = .014). No such relation was demonstrated in the central brain. MDz in the corpus callosum was independently associated with the microbleed concentration in the structures connected by WM tracts running through the corpus callosum (B = 20.0 [95% CI 24.8–75.2], P < .000). MDz in the central brain was independently associated with the microbleed concentration in the cerebral hemispheres (B = 25.7 [95% CI 3.9–47.5], P = .023).CONCLUSIONS:SWI-assessed microbleeds in the subacute phase are associated with DTI-based WM integrity in the chronic phase. These associations are found both within regions and between functionally connected regions.

The yearly incidence of traumatic brain injury (TBI) is around 300 per 100,000 persons.1,2 Almost three-quarters of patients with moderate to severe TBI have traumatic axonal injury (TAI).3 TAI is a major predictor of functional outcome,4,5 but it is mostly invisible on CT and conventional MR imaging.6,7DTI provides direct information on WM integrity and axonal injury.5,8 However, DTI abnormalities are neither specific for TAI nor stable over time. Possibly because of the release of mass effect and edema and resorption of blood products, the effects of concomitant (non-TAI) injury on DTI are larger in the subacute than in the chronic phase (>3 months).4,9,10 Therefore, DTI findings are expected to reflect TAI more specifically in the chronic than in the subacute phase (1 week–3 months).4 Even in regions without concomitant injury, the effects of TAI on DTI are dynamic, possibly caused by degeneration and neuroplastic changes.6,11,12 These ongoing pathophysiological processes possibly contribute to the emerging evidence that DTI findings in the chronic phase are most closely associated with the eventual functional outcome.12,13Although DTI provides valuable information, its acquisition, postprocessing, and interpretation in individual patients are demanding. SWI, with which microbleeds can be assessed with high sensitivity, is easier to interpret and implement in clinical practice. In contrast to DTI, SWI-detected traumatic microbleeds are more stable1 except in the hyperacute14,15 and the late chronic phases.16 Traumatic cerebral microbleeds are commonly interpreted as signs of TAI. However, the relation is not straightforward. On the one hand, nontraumatic microbleeds may be pre-existing. On the other hand, even if traumatic in origin, microbleeds represent traumatic vascular rather than axonal injury.17 Indeed, TAI is not invariably hemorrhagic.18 Additionally, microbleeds may secondarily develop after trauma through mechanisms unrelated to axonal injury, such as secondary ischemia.18DTI is not only affected by pathophysiological changes but also by susceptibility.19 The important susceptibility-effect generated by microbleeds renders the interpretation of DTI findings at the location of microbleeds complex. In the chronic phase, mean diffusivity (MD) is the most robust marker of WM integrity.4,6 For these reasons, we evaluated MD in the normal-appearing WM.Much TAI research focuses on the corpus callosum because it is commonly involved in TAI5,18,20 and it can reliably be evaluated with DTI,5,21 and TAI in the corpus callosum is related to clinical prognosis.6,20 The corpus callosum consists of densely packed WM tracts that structurally and functionally connect left- and right-sided brain structures.22 The integrity of the corpus callosum is associated with the integrity of the brain structures it connects.23 Therefore, microbleeds in brain structures that are connected through the corpus callosum may affect callosal DTI findings. Analogous to this, microbleeds in the cerebral hemispheres, which exert their function through WM tracts traveling through the deep brain structures and brain stem,24,25 may affect DTI findings in the WM of the latter.Our purpose was to evaluate whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase. We investigated this relation within the cerebral hemispheres and the central brain and between regions that are functionally connected by WM tracts.  相似文献   
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Background:Acute ischemic stroke (AIS) is an important factor leading to adult death and disability globally. For AIS patients who meet certain conditions, recombinant tissue plasminogen activator (rt-PA) intravenous thrombolysis is an important method recommended by national guidelines to achieve vascular recanalization. However, complications such as hemorrhagic transformation and vascular reocclusion after thrombolysis are still unsolved problems in clinical. Several systematic reviews of clinical randomized controlled trials (RCTs) in the past have shown that Chinese herbal injections (CHIs) can improve the neurological function of patients, increase the tolerance of ischemic tissues to hypoxia, and inhibit platelet aggregation. Therefore, this study conducted a meta-analysis of AIS treatment with intravenous thrombolysis alone and compared it with the combined application of CHIs. To evaluate whether CHIs have a synergistic effect on thrombolytic therapy and provide a basis for clinical application.Methods:The following databases will be searched until September 2020: ①English databases: PubMed, Cochrane Library, Embase; ②Chinese databases: CNKI, Wanfang database, Weipu database, SinoMed. RCTs will be included to compare the efficacy of thrombolysis combined with CHIs and thrombolysis alone in the treatment of AIS. Data extraction and risk of bias assessments will be carried out by 2 verifiers independently. The risk of bias will be evaluated through the Cochrane risk of bias tool. Review Manager software 5.3 will be used for statistical analysis.Results:This study will provide comprehensive evidence for the treatment of AIS by CHIs combined with intravenous thrombolysis from multiple aspects.Conclusion:The conclusion of the meta-analysis will provide a basis for judging whether CHIs combined with intravenous thrombolysis is an effective measure for the treatment of AIS.Ethics and dissemination:Ethical approval is not needed because this study will be based on data that already published. We will publish the findings of this study in a peer-reviewed journal and related conferences.PROSPERO registration number:CRD42020215546.  相似文献   
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Herpesvirus entry mediator (HVEM) displays dual signals in T-cell activation according to the ligands and intracytoplasmic effectors it interacts with. High HVEM expression may play an immunosuppressive role in several malignancies. The present study investigated the clinical impact of HVEM on intrahepatic cholangiocarcinoma (ICC), including its prognostic value, and association with clinicopathological features and immune status. The clinical data of 102 consecutive patients with ICC who underwent surgical treatment from January 2012 to December 2017 were collected. The expression of HVEM and different types of tumor-infiltrating lymphocytes (TILs) were investigated in ICC tissue samples by immunohistochemical staining. HVEM expression was detected in the tumor tissues of 92 (90.2%) patients with ICC. Patients with high HVEM expression were more likely to have increased peripheral blood lymphocyte (PBL) concentrations (P=0.031), decreased CEA (P=0.036), low TNM stage (P=0.043) and high frequencies of small-duct histological type (P=0.021) and BAP1 retained expression (P=0.010). Survival analysis showed that high HVEM expression was a favorable independent predictor of overall postoperative survival (P=0.034, hazard ratio=0.486, 95% confidence interval=0.249–0.945). In addition, no significant association of HVEM expression with CD4+ (P=0.512), CD8+ (P=0.750) or CD45RO+ (P=0.078) TILs was identified in the ICC tissues. These results indicate that HVEM may serve as a favorable prognostic marker for ICC. Furthermore, co-stimulatory signals from HVEM may play a dominant role in the progression of ICCs, which can be explained by an increase in the number of PBLs rather than a change in the number of TILs. However, the function of the HVEM network in ICC progression is complex and requires further study.  相似文献   
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A 21‐year‐old female presented with a 5‐year history of an erythematous papule on her right breast. The biopsy showed a dense, dermal nodular infiltrate, extending focally into the subcutaneous tissue. The infiltrate was composed predominantly of pleomorphic cells with bi‐lobed, multi‐lobed, horseshoe, or ring‐shaped nuclei. There was a smaller subset of monomorphous cells characterized by a round, reniform, or elongated single‐lobed nucleus. Accompanying cells included few foamy histiocytes, lymphocytes, and numerous scattered eosinophils. No necrosis, vascular invasion, or ulceration was present. The pleomorphic and monomorphic granular cells were positive for Giemsa stain as well as for tryptase, CD117, CD68, CD2, and CD30 immunohistochemistry and negative for S100, CD1a, myeloperoxidase, lysozyme, and CD56. Clinical examination was negative for any additional similar lesions and serum tryptase was within normal limits. The bone marrow was not biopsied. In addition, fluorescent in situ hybridization revealed multiple clones with loss of number 5 chromosome and PDGFRA and HRAS mutations. The lesion did not recur or progress after a 6‐year clinical follow‐up. To our full knowledge, we report the first case of pleomorphic mastocytoma with loss of chromosome 5 and PDGFRA and HRAS mutations.  相似文献   
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