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1.
Ceramide synthases (CerS) synthesise ceramides of defined acyl chain lengths, which are thought to mediate cellular processes in a chain length-dependent manner. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), we observed a significant elevation of CerS2 and its products, C24-ceramides, in CD11b+ cells (monocytes and neutrophils) isolated from blood. This result correlates with the clinical finding that CerS2 mRNA expression and C24-ceramide levels were significantly increased by 2.2- and 1.5-fold, respectively, in white blood cells of MS patients. The increased CerS2 mRNA/C24-ceramide expression in neutrophils/monocytes seems to mediate pro-inflammatory effects, since a specific genetic deletion of CerS2 in blood cells or a total genetic deletion of CerS2 significantly delayed the onset of clinical symptoms, due to a reduced infiltration of immune cells, in particular neutrophils, into the central nervous system. CXCR2 chemokine receptors, expressed on neutrophils, promote the migration of neutrophils into the central nervous system, which is a prerequisite for the recruitment of further immune cells and the inflammatory process that leads to the development of MS. Interestingly, neutrophils isolated from CerS2 null EAE mice, as opposed to WT EAE mice, were characterised by significantly lower CXCR2 receptor mRNA expression resulting in their reduced migratory capacity towards CXCL2. Most importantly, G-CSF-induced CXCR2 expression was significantly reduced in CerS2 null neutrophils and their migratory capacity was significantly impaired. In conclusion, our data strongly indicate that G-CSF-induced CXCR2 expression is regulated in a CerS2-dependent manner and that CerS2 thereby promotes the migration of neutrophils, thus, contributing to inflammation and the development of EAE and MS. 相似文献
2.
A. AbuKaraky M. Al Mousa O.A. Samara Z.H. Baqain 《International journal of oral and maxillofacial surgery》2021,50(6):798-800
Pseudoaneurysms in the external carotid artery system are rare, mostly reported in the superficial temporal and facial arteries. The bilateral sagittal split osteotomy has a low incidence of complications requiring emergency interventions. We report the case of a patient with acute bleeding from a pseudoaneurysm of the inferior alveolar artery diagnosed by angiography and treated successfully by super-selective embolization. 相似文献
3.
Rationale:Tarlov or perineurial cysts are nerve root lesions often found in the sacral region. Most perineural cysts (PCs) remain asymptomatic throughout a patient''s life. While their pathogenesis is still unclear, trauma resulting in hemorrhaging into subarachnoid space has been put forward as a possible cause of these cysts. Recently, we worked with a patient experiencing symptomatic PCs after spontaneous subarachnoid hemorrhage.Patient concerns:A 45-year-old man had a coil embolization procedure performed after being diagnosed with a subarachnoid hemorrhage from a ruptured anterior communicating artery. His symptoms were relieved after the procedure, but 7 days later he reported worsening pain in the left perineal area. The pain was intermittent at its onset and exacerbated by sitting, walking, and coughing.Diagnoses:Two weeks after the embolization procedure, a lumbar spine MRI revealed 2 PCs at the S1 and S2 level affecting the left S2 root with high signal intensity in T2 and T1 images, suggestive of bleeding within the cyst.Interventions:We operated using a posterior approach. Cyst fenestration was done after S1 laminectomy. We aspirated approximately 1 cc of old blood.Outcomes:His pain was relieved immediately after cyst removal and no neurologic deterioration occurred during the postoperative period.Lessons:Subarachnoid hemorrhage can be the source of the development of pain from asymptomatic PCs, making them symptomatic. Surgical extirpation is 1 treatment option for these symptomatic PCs. 相似文献
4.
BackgroundCarbetocin has been found to be superior to oxytocin in terms of need for additional uterotonics and prevention of postpartum haemorrhage at caesarean delivery. However, this is based on combined data from labouring and non-labouring parturients and it remains unclear how effective carbetocin is in the purely elective setting. The aim of this review was to compare carbetocin to oxytocin in elective caesarean delivery.MethodsMedline, Embase, CINAHL, Web of Science, and the Cochrane databases were searched for randomised controlled trials in any language. The primary outcome was need for additional uterotonics. Secondary outcomes were mean blood loss, need for blood transfusion and incidence of postpartum haemorrhage >1000 mL.ResultsNine studies with a total of 1962 patients were included. Trial sequential analysis confirmed that the information size (n=1692) had surpassed that required (n=1166) in order to demonstrate a statistically significant reduction in the use of additional uterotonics. Need for additional uterotonics was reduced by 53% with carbetocin compared to oxytocin (OR 0.47, 95% CI 0.34 to 0.64; P <0.001, I2=63.5). The number needed-to-treat was 11. The risk of bias, data heterogeneity and inconsistency in reporting bleeding outcomes made it difficult to reach definite conclusions about prevention of PPH.ConclusionsCarbetocin is associated with a reduced need for additional uterotonics when compared with oxytocin at elective caesarean delivery. Standardisation of bleeding-related outcomes in studies is necessary to facilitate synthesis of data in future analyses. 相似文献
5.
《Paediatrics & Child Health》2019,29(8):339-344
Von Willebrand Disease is a common cause of excessive bruising and bleeding in children. This short article gives advice on diagnosis and management for paediatricians. Given its prevalence and presenting symptoms, VWD should always be considered in the assessment of children suspected of non-accidental injury. Its diagnosis can be challenging, not only because of the various subtypes of the disorder but because of the considerable overlap between VWD and normal individuals. Laboratory diagnosis requires a range of quantitative and qualitative tests of the VWF protein, with targeted gene analysis increasingly used to confirm the diagnosis of type 2 and type 3 VWD. Bleeding Assessment Tools may be helpful in directed laboratory testing but are often less so in young children who have had limited haemostatic challenges. Treatment for VWD includes the use of antifibrinolytic drugs, vasopressin or VWF-containing clotting factor concentrates. Treatment is often on-demand for individual bleeding episodes but there are specific indications for the use of prophylactic treatment in children. 相似文献
6.
《Archivos de la Sociedad Espa?ola de Oftalmología》2019,94(8):409-412
The case concerns a 20 year-old woman with a sudden visual loss in her left eye. In the fundus examination, a focal pre-retinal haemorrhage was observed in the superior temporal vascular branch with accompanying vitreous haemorrhage. There was a favourable spontaneous outcome. Eighteen months later, she presented with a new visual loss in the same eye, showing a sub-hyaloid pre-macular haemorrhage that was satisfactorily drained by hyaloidotomy using a Nd-YAG laser. The patient had also presented with an upper digestive tract haemorrhage and menorrhagia. A haemostasis study was performed that showed a coagulation factor VII deficiency. This is a very uncommon disorder that has not been previously described in association with the appearance of pre-retinal haemorrhages. 相似文献
7.
8.
目的 :观察MDA-7/IL-24基因对肝癌的选择性杀伤作用,为肝癌的基因治疗提供理论基础。 方法 :将携带人MDA-7/IL-24基因的腺病毒Ad.mda-7感染人正常肝细胞L02和肝癌细胞HepG2;用RT-PCR法观察MDA-7/IL-24基因的表达;ELISA方法检测细胞培养上清液中MDA-7/IL-24蛋白的浓度;4甲基偶氮唑蓝染色法(MTT)及Hoechst染色观察MDA-7/IL-24对肝癌细胞的生长抑制和杀伤作用;Annexin-V和PI双染后流式细胞仪检测2种细胞的凋亡;用流式细胞仪检测细胞周期。 结果 :复制缺陷型腺病毒能介导外源基因MDA-7/IL-24在肝癌细胞株HepG2和正常细胞L02中的高效表达;细胞培养上清液中有MDA-7/IL-24蛋白的表达; MDA-7/IL-24能明显抑制肝癌细胞生长并可促进肝癌细胞的凋亡;MDA-7/IL-24阻滞肝癌细胞于G2/M期,能选择性杀伤肝癌细胞而对正常的肝细胞无阻滞作用和毒性作用。结论 :复制缺陷型重组腺病毒载体Ad.mda-7能介导MDA-7/IL-24基因在人肝癌细胞中高效表达,促使细胞增殖阻滞及诱导肿瘤细胞凋亡,选择性地杀伤肝癌细胞HepG2,而对正常肝细胞L02无任何毒性作用。 相似文献
9.
急性脑血管病肿瘤坏死因子-α的临床研究 总被引:1,自引:0,他引:1
目的:探讨肿瘤坏死因子-α(TNF-α)在急性脑血管病(ACVD)中的作用及其变化的临床意义。方法:选取95例ACVD患者,并设性别及年龄相匹配的血清对照组(20例)及脑脊液对照组(10例)。应用酶联免疫吸附法(ELISA)于发病后第1、3、7、14d测定血清和脑脊液中TNF-α。结果:①三种脑血管病患者血清TNF-α动态变化存在差异,脑出血和脑梗死组的峰值单间为发病后第3d,而蛛网膜下腔出血(SAH)组为第1d。②脑梗死患者血清TNF-α水平与梗死面积、神经功能缺损程度及病情恶化与否相关。③SAH组于发病后第1d、3d、7d脑脊液TNF-α值高于血清,14d时降至对照组水平并与血清无差异。结论:①脑梗死患者血清TNF-α的动态观察,可为临床预测梗死灶大小、神经功能缺损程度及病情恶化与否提供依据。②发病早期的脑梗死患者若CT未能显示病灶时,血清TNF-α的明显升高有助于临床诊断和治疗。③SAH患者脑脊液中TNF-α水平明显高于血清,进一步提示脑内神经组织可产生TNF-α。脑脊液中TNF-α的持续明显升高可能与SAH后脑血管痉挛有关。④TNF-α参与了ACVD的炎性反应过程,早期抑制TNF产生及抗炎性反应的治疗可能具有潜在的临床价值。 相似文献
10.
Dissociation of GFAP intermediate filaments in EAE: observations in the lumbar spinal cord 总被引:1,自引:0,他引:1
Acute experimental allergic encephalomyelitis (EAE) in the Lewis rat is a cell-mediated autoimmune disease of central nervous system myelin. The lesion has been characterized by breakdown of the blood-brain barrier, edema, and periventricular infiltration of macrophages and lymphocytes. At the early stage of the disease, the astrocytes show a marked increase in immunostaining for glial fibrillary acidic protein (GFAP). A corresponding increase in GFAP content, however, cannot be demonstrated. Electron microscopic examination of the early lesion shows a typical reactive astrocytic response expressed by an enlarged watery cytoplasm, particularly at the level of the processes surrounding neurons and blood vessels and in the neuropil itself. The astroglial processes contain numerous glycogen particles (aggregates and single particles). Glial filaments are also conspicuous and are arranged in small bundles or loose thin filaments adjacent to the bundles. The glial filaments that normally appear as tight bundles have expanded and appear less dense. We suggest that the increase in GFAP immunostaining of the astrocytes in the early lesion is due in part to edema, which causes dissociation of the filaments and thereby exposes more antigenic sites to the antibodies. 相似文献