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81.
两种新生儿缺血缺氧性脑病模型建模方法的比较   总被引:6,自引:0,他引:6  
目的比较两种新生儿缺血缺氧性脑病(HIE)模型建模方法的差异,探讨麻醉和动物缺血缺氧间期对HIE动物模型的影响。方法采用7d龄SD乳鼠建立HIE模型。传统组动物乙醚麻醉后结扎左侧颈总动脉,休息2~3h,同时人37℃水溶闭缺氧箱,持续充以8%氧+92%氮的混合气体,气流量1L/min,维持2.5h。改进组动物动脉结扎手术前动物不予麻醉,且术后动物不作休息立即进行缺氧。比较建模过程中两组动物的存活情况;光镜下观察建模后3d两组动物左侧大脑半球的病理变化情况,并比较两组动物病理总评分的差异。结果改进组建模过程中所有动物未见死亡,传统组建模过程中6只动物死亡(P〈0.025)。建模后3d,改进组动物脑组织变性、坏死显著,病理总评分550分,传统组大部分动物脑组织未见明显病变,总评分130分(P〈0.01)。结论传统HIE建模方法动物在建模过程中死亡率高,而存活的模型动物病理变化却不确切。改进的HIE建模方法模型动物个体之间均衡性好,脑部病变确切,建模过程中动物死亡率低,值得推广。  相似文献   
82.
《山东中医杂志》2017,(10):872-875
目的 :观察针刺十三鬼穴结合西医治疗对肝性脑病患者血氨、β-内啡肽水平的影响。方法 :86例肝性脑病患者随机分为治疗组44例和对照组42例。对照组予门冬氨酸鸟氨酸、支链氨基酸静脉滴注治疗,治疗组在对照组治疗基础上加用针刺十三鬼穴,治疗1周后,评价疗效,复查肝功能、血氨、β-内啡肽的变化,与治疗前进行对比。结果:总有效率对照组69.0%,治疗组90.9%,两组比较差异有统计学意义(P0.05)。治疗组肝功能、血氨、β-内啡肽的下降程度显著优于对照组,差异有统计学意义(P0.05)。结论:在西药治疗的基础上针刺十三鬼穴,可增强西药对肝性脑病的治疗效果,改善患者肝功能,显著降低肝性脑病患者血氨、β-内啡肽的水平。  相似文献   
83.
The incidence of liver disease continues to increase and is now one of the leading causes of death in the United Kingdom. The increasing prevalence of viral hepatitis combined with a surge in the incidence of both alcohol and obesity related liver disease mean that critical care units are increasingly being called upon to assist in managing those with life-threatening complications or end-stage liver disease. Decompensated cirrhosis is not a single organ illness but a complex multi-system disorder typified by impaired immunity, malnutrition and multi-organ failure and presents a significant challenge to the critical care physician. In this article we describe the epidemiology, aetiology and pathophysiology of decompensated liver disease and describe the management strategies of a range of resulting clinical complications.  相似文献   
84.
催产素减轻新生大鼠海马神经元缺氧缺血性损伤   总被引:1,自引:1,他引:0       下载免费PDF全文
目的:探讨催产素(oxytocin)对新生大鼠缺氧缺血性损伤后海马CA1区神经元的作用及机制。方法:采用氧糖剥夺(OGD)制备体外缺氧缺血模型,取8只7~10日龄新生大鼠的急性分离脑片(6~8片/只)随机分为4组,即对照组、OGD 20 min组、OGD 40 min组和OGD+oxytocin组,进行TO-PRO-3染色实验观察催产素对神经元的作用。另取20只新生大鼠脑片随机分为4组,分别是OGD组、OGD+oxytocin组、OGD+d VOT(催产素受体阻断剂)+oxytocin组和OGD+bicuculline(GABAA受体阻断剂)+oxytocin组,用全细胞膜片钳记录不同药物作用下海马神经元缺氧去极化的出现时间。结果:TO-PRO-3染色结果显示海马CA1区神经元死亡数量随着氧糖剥夺时间延长而增加,催产素能显著减少OGD所致的死亡神经元数目(P0.05)。全细胞膜片钳记录结果显示,催产素可使缺氧去极化时间显著延长;d VOT及bicuculline可以消除这种效应。结论:催产素能减轻新生大鼠海马CA1区神经元缺氧缺血性损伤,其机制可能是通过结合催产素受体,增强抑制性神经传递,从而产生神经保护作用。  相似文献   
85.
Mutations in the X-linked gene CDKL5 cause early-onset epileptic encephalopathy and severe developmental delay. Because this disorder predominantly affects females, the full clinical spectrum of male patients remains elusive. We herein report a 16-year-old boy, who suffered from intractable seizures 20 days after birth. Serial electroencephalograms detected recurrent focal epileptiform discharges from age 4 months, which evolved to hypsarrhythmia later in infancy. Mass-spectrometric analyses revealed increase in urinary excretion of methylmalonic acid without perturbed concentrations of propionic acid, homocystein and methionine. Whole-exome sequencing identified a de novo, truncating mutation in CDKL5 (NM_003159.2:c.419dupA, p.Asn140Lysfs*8). Targeted sequencing excluded concomitant mutations in methylmalonic academia-associated genes. No methylmalonic acidemia has been reported in children with CDKL5 disorder. Extensive analyses on organic acid metabolism for males with CDKL5 mutations will gain more insight into their biochemical profiles in infancy.  相似文献   
86.
Somatic mosaicism in single nucleotide variants of SCN1A is known to occur in a subset of parents of children with Dravet syndrome (DS). Here, we report recurrent somatic mosaic microdeletions involving SCN1A in children diagnosed with DS. Through the evaluation of 237 affected individuals with DS who did not show SCN1A or PCHD19 mutations in prior sequencing analyzes, we identified two children with mosaic microdeletions covering the entire SCN1A region. The allele frequency of the mosaic deletions estimated by multiplex ligation‐dependent probe amplification and array comparative genomic hybridization was 25–40%, which was comparable to the mosaic ratio in lymphocytes and buccal mucosa cells observed by fluorescence in situ hybridization analysis. The minimal prevalence of SCN1A mosaic deletion is estimated to be 0.9% (95% confidence level: 0.11–3.11%) of DS with negative for SCN1A and PCDH19 mutations. This study reinforces the importance of somatic mosaicism caused by copy number variations in disease‐causing genes, and provides an alternative spectrum of SCN1A mutations causative of DS. Somatic deletions in SCN1A should be considered in cases with DS when standard screenings for SCN1A mutations are apparently negative for mutations.
  相似文献   
87.
Chronic traumatic encephalopathy (CTE) is an acquired primary tauopathy with a variety of cognitive, behavioral, and motor symptoms linked to cumulative brain damage sustained from single, episodic, or repetitive traumatic brain injury (TBI). No definitive clinical diagnosis for this condition exists. In this work, we used [F-18]FDDNP PET to detect brain patterns of neuropathology distribution in retired professional American football players with suspected CTE (n = 14) and compared results with those of cognitively intact controls (n = 28) and patients with Alzheimer’s dementia (AD) (n = 24), a disease that has been cognitively associated with CTE. [F-18]FDDNP PET imaging results in the retired players suggested the presence of neuropathological patterns consistent with models of concussion wherein brainstem white matter tracts undergo early axonal damage and cumulative axonal injuries along subcortical, limbic, and cortical brain circuitries supporting mood, emotions, and behavior. This deposition pattern is distinctively different from the progressive pattern of neuropathology [paired helical filament (PHF)-tau and amyloid-β] in AD, which typically begins in the medial temporal lobe progressing along the cortical default mode network, with no or minimal involvement of subcortical structures. This particular [F-18]FDDNP PET imaging pattern in cases of suspected CTE also is primarily consistent with PHF-tau distribution observed at autopsy in subjects with a history of mild TBI and autopsy-confirmed diagnosis of CTE.The consensus statement on concussions from the Fourth International Conference on Concussion in Sports (Zurich 2012) (1) defines acute mild traumatic brain injury (mTBI) or cerebral concussion as a brain injury with a complex pathophysiological process induced by biomechanical forces. Cerebral concussion causes white matter axonal injury due to axonal shearing and stretching (2), typically resulting in the rapid onset of short-lived impairment of neurological function that resolves spontaneously and largely reflects a functional disturbance rather than a structural injury. As such, no abnormality is seen on standard structural neuroimaging determinations (1).A number of early literature reports described a neurodegenerative disease associated with a history of repetitive TBI in retired professional boxers (3, 4), with a prevalence rate of up to 47% among retired professional boxers aged 50 y and older who boxed for more than 10 y (5). Initially named “punch drunk syndrome” (3) and dementia pugilistica (4), this syndrome is now known as chronic traumatic encephalopathy (CTE) in the current literature (6, 7).Compelling autopsy evidence (68) and neurobehavioral determinations (9) of retired professional American football athletes indicate that a subgroup develops neurodegenerative and clinical changes typical of CTE, a progressive syndrome distinctively different from Alzheimer’s disease (AD), which is the most common form of dementia in the elderly (10). The connection between multiple concussions and subconcussive head impacts (2) and CTE is compelling, because history of repetitive concussions is the strongest risk factor for development of CTE in numerous contact sports (e.g., American football, rugby, boxing, ice hockey, soccer, and professional wrestling), in war veterans with a history of blast or blunt force TBI, and in conditions where trauma to the head occurs for various reasons (e.g., falls during seizures, head-banging in autistic children, motor vehicle and domestic accidents, domestic violence and abuse) (6, 8, 1114). As with most neurodegenerative diseases, clinical diagnosis remains elusive due to the lack of specificity of CTE clinical symptomatology criteria, and histopathological examination of brain at autopsy is the most definitive diagnostic modality (6, 8, 11).The novel imaging approaches leading to the in vivo characterization of CTE brain neuropathology premortem (e.g., PET) are complementary to structural imaging modalities [e.g., diffusion tensor imaging MRI (DTI MRI)] and offer a specific and sensitive strategy to facilitate diagnosis of CTE. Neuronal and glial fibrillar hyperphosphorylated microtubule-associated protein tau deposits composed of paired helical filament (PHF)-tau are the primary brain proteinopathy of CTE based on autopsy determinations, and their 3R/4R tau isoform ratio is similar to that of AD (11). Their topographically predictable pattern of distribution was used as a basis for a severity staging system of CTE neuropathology (7), ranging from mild (neuropathology stages I and II) to advanced (neuropathology stages III and IV) (7) (Tables S1 and S2). In addition, more than 80% of analyzed pathologically confirmed CTE cases also show transactive response (TAR) DNA-binding protein of ∼43 kDa (TDP-43) either as inclusions in sparse neurites in cortex, medial temporal lobe structures, and brainstem in CTE neuropathology stages I–III, as widespread neuronal and glial inclusions in severe CTE cases (neuropathology stage IV), or in CTE cases with motor neuron disease (7, 15) (Tables S1 and S2). CTE cases also can exhibit the presence of other fibrillar protein aggregates. McKee et al. (7) and Omalu et al. (8) reported that in autopsy determinations, less than half of all CTE cases and less than one third of “pure” CTE cases show amyloid-β (Aβ) deposits, predominantly as scattered cortical diffuse plaques in low density (Tables S1 and S2). Of note is that subjects with Aβ deposits were significantly older than those without. Moreover, their neuropathology was more severe than that in cases without Aβ deposits and was often combined with α-synuclein deposits (7). As an example, as reported by McKee et al. (7), of 30 CTE cases with at least some cortical Aβ deposits (of 68 confirmed CTE cases), 29 brains were from subjects who died in their seventh decade of life and one from a subject who died in his sixth decade.Subsequent to our preliminary report (16), in this work we use [F-18]FDDNP, an imaging agent for fibrillar insoluble protein aggregates (1620), and PET imaging with the aim of establishing (i) topographic brain localization of [F-18]FDDNP PET signals indicative of fibrillar neuroaggregates in retired professional American football players with suspected CTE (mTBI group) vs. controls (CTRL); (ii) determination of [F-18]FDDNP PET signal patterns in the mTBI group; (iii) presence of [F-18]FDDNP PET signal as a measure of neuropathology in the brain areas involved in mood disorders related neurocircuits; (iv) correlation of [F-18]FDDNP PET results with neuropathology distributions in confirmed CTE cases; (v) differential patterns of [F-18]FDDNP PET signals, and thus deposition of fibrillar neuroaggregates, in the mTBI group with respect to the AD group; and (vi) preliminary demonstration of differences in [F-18]FDDNP PET signal patterns in mTBI cases with different etiology, i.e., contact-sport–related mTBI in retired professional American football players vs. blast-induced mTBI in war veterans. We further intended to demonstrate that tau (vs. Aβ) specificity of high affinity PET molecular imaging probes may not be a necessary requirement when used in CTE subjects with primary proteinopathy in the form of PHF-tau (8): PET imaging probes potentially sensitive to TDP-43 aggregates and Aβ deposits, which are present in higher densities almost exclusively in older CTE cases with more advanced neuropathology (e.g., stage IV), could better define disease progression based on quantification of differences in regional loads of combined neuropathologies because additional neuropathologies appear in predictable topographical and temporal patterns.  相似文献   
88.
《Brain & development》2022,44(2):122-130
BackgroundAcute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is characterized by biphasic seizures and white matter lesions with reduced diffusion, which are often accompanied by involuntary movements. The neurological outcomes of AESD vary from normal to mild or severe sequelae, including intellectual disability, paralysis, and epilepsy. The present study aimed to clarify the prognostic factors of AESD, including involuntary movements.MethodsWe enrolled 29 patients with AESD admitted to Tottori University Hospital from 1991 to 2020 and retrospectively analyzed their clinical data. Neurological outcomes were assessed by the Pediatric Cerebral Performance Category score and cerebral paralysis as neurological sequelae.ResultsOf the 29 patients, 12 had favorable outcomes and 17 had unfavorable outcomes. Univariate analysis revealed that the presence of underlying diseases, a decline in Glasgow Coma Scale (GCS) score 12–24 h after early seizures, and involuntary movements were associated with unfavorable outcomes. In multivariate analysis, a decline in GCS score and involuntary movements were associated with unfavorable outcomes. The sensitivities and specificities of underlying diseases, a decline of ≥ 3 points in GCS score 12–24 h after early seizures, and involuntary movements for unfavorable outcomes were 53% and 92%, 92% and 65%, and 59% and 92%, respectively.ConclusionsThe appearance of involuntary movements may be associated with unfavorable outcomes of AESD. The prognostic factors identified herein are comparable with previously known prognostic factors of consciousness disturbances after early seizures.  相似文献   
89.
《Brain & development》2022,44(3):210-220
ObjectiveBiomarkers predicting poor outcomes of status-epilepticus-associated-with-fever (SEF) at an early stage may contribute to treatment guidance. However, none have been reported thus far. We investigated the dynamics of serum growth and differentiation factor (GDF)-15 after seizure onset in patients with SEF and determined whether GDF-15 can predict poor outcomes, particularly in the first 6 h after seizure onset.MethodsWe enrolled 37 pediatric patients with SEF and eight patients with simple febrile seizures (SFS) and collected their blood samples within 24 h of seizure onset and eight febrile control patients between March 1, 2017 and September 30, 2020. All patients were aged ≤15 years.ResultsIn the SEF group, the median post-seizure serum GDF-15 values were 1,065 (<6h), 2,720 (6–12 h), and 2,411 (12–24 h) pg/mL. The median serum GDF-15 in the first 6 h was measured in patients with SEF without a significant past medical history (n = 21) and was found to be statistically significantly higher (1,587 pg/mL) than in the febrile control (551 pg/mL) and SFS (411 pg/mL) groups. The median serum GDF-15 was statistically significantly higher in patients with SEF with sequelae (n = 5) and patients with acute encephalopathy with biphasic seizures/reduced diffusion/hemorrhagic shock and encephalopathy syndrome (n = 6) than in patients with SEF without sequelae (n = 16) (15,898 vs 756 pg/mL) and patients with prolonged FS (n = 15) (9,448 vs 796 pg/mL).ConclusionsThis study demonstrates the dynamics of serum GDF-15 in patients with SEF and indicates the potential of GDF-15 as an early predictor of poor outcomes.  相似文献   
90.
《Brain & development》2022,44(3):249-253
IntroductionKIF1A, a gene that encodes a neuron-specific motor protein, plays important roles in cargo transport along neurites. Variants in KIF1A have been described in three different disorders, and neurodegeneration and spasticity with or without cerebellar atrophy or cortical visual impairment syndrome (NESCAVS) is the severest phenotype.Case reportA 3-year-old girl was born at term with a birth weight of 2590 g. At five months of age, she visited our hospital due to developmental delay. An EEG showed multiple epileptic discharge, and a nerve conduction study showed severe axonopathy of both motor and sensory nerves. We performed exome sequencing and identified a de novo heterozygous missense variant in KIF1A (NM_001244008.1: c. 757G > A, p.E253K). At six months of age, she developed acute encephalopathy, multiple organ failure and disseminated intravascular coagulation, necessitating intensive care. Her brain CT showed severe brain edema, followed by profound brain atrophy. We diagnosed hemorrhagic shock and encephalopathy syndrome (HSES) according to the clinico-radiological features. Currently, she is bed-ridden, and requires gastrostomy because of dysphagia.ConclusionThe clinical course of our case confirmed that p.E253K is associated with severe neurological features. Severe KIF1A deficiency could cause thermoregulatory dysfunction and may increase the risk of acute encephalopathy including HSES.  相似文献   
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