丙泊酚对N-甲基-D-天冬氨酸所致PC12细胞损伤的保护作用

目的　探讨静脉麻醉药丙泊酚 (PPF)脑保护作用的可能机制。方法　乳酸脱氢酶 (LDH)法及MTT比色法判断细胞损伤程度及细胞存活率 ,Fura 2 /AM荧光标记法测定细胞内Ca2 + 浓度 ( [Ca2 + ]i)的变化 ,分光光度法测定细胞一氧化氮合酶 (NOS)活性。结果　N 甲基 D 天冬氨酸 (NMDA) 3 0 0 μmol·L-1处理4h可明显导致PC1 2细胞的损伤 ,表现为LDH释放量明显增加 ,吸光度值A570nm明显降低 ,细胞存活率降低 ,同时 [Ca2 + ]i 和NOS活性则明显增加。PPF6.2 5 ,2 5 ,1 0 0 ,40 0 μmol·L-1与NMDA同时处理PC1 2细胞则使LDH释放量显著降低 ,细胞存活率增加。PPF 1 2 .5和 1 2 5 μmol·L-1可显著降低NMDA诱导的[Ca2 + ]i 水平及NOS活性的提高。结论　PPF对NMDA所致的PC1 2细胞损伤有明显的保护作用 ,其机制可能与其抑制NMDA受体的功能 ,降低 [Ca2 + ]i,减弱Ca2 + 超载 ,并降低NMDA诱导的NOS活性增加有关。提示PPF可能是通过抑制NMDA受体 Ca2 + NOS通路的功能而产生细胞保护效应     

Serum alanine aminotransferase activity in obese children

To confirm the significance of the serum alanine aminotransferase (ALT) test for the diagnosis of fatty liver and to clarify the relationship between serum ALT activity and the duration of obesity, we analysed 310 obese young schoolchildren (195M, 115F), who were classified into three duration groups (1–3 y, 4–6 y, 7+ y), three age groups (6–7 y, 8–9 y, 10–11 y), and four obesity groups (weight excess; mild, 20–29%: moderate, 30–39%; severe. 40–49%; very severe. 50%). Seventy-seven patients with abnormal ALT test, >30 IU/1, and 27 patients with normal ALT test were examined by ultrasound study to identify the fatty-fibrotic pattern of the liver. Abnormal results of the serum ALT test were found in 24% of all patients. The fatty-fibrotic pattern was identified in 64/77 (83%) patients with abnormal ALT test and in 5/27 (18%) patients with normal ALT test. The serum ALT test has a sensitivity of 0.92 for detecting the fatty-fibrotic pattern proven by ultrasound study Frequencies of cases with abnormal serum ALT levels increased with the duration of obesity. In the shortest duration group, however, the frequencies of abnormal results in serum ALT test did not increase with advanced ages or the grades of obesity. In conclusion, the present study confirmed the usefulness of the serum ALT test for screening fatty liver, and showed that a longer duration of obesity is generally associated with the occurrence of fatty liver in a paediatric obese population. In young patients with mild obesity or a short duration of obesity, however, fatty liver or fatty fibrosis may develop. Early intervention should be made in the case of obese children.     

门冬氨酸左氧氟沙星与其他左氧氟沙星盐的药动学比较

目的对门冬氨酸左氧氟沙星与其他左氧氟沙星盐在大鼠体内进行了药动学比较。方法以替硝唑为内标,血浆样品经乙腈沉淀蛋白后,采用高效液相的方法进行了测定。结果线性范围0.5~25μg/m l,日内、间精密度RSD均<6%,平均回收率大于89%。大鼠腹腔注射门冬氨酸左氧氟沙星、盐酸左氧氟沙星、乳酸左氧氟沙星和左氧氟沙星,测定不同时间的药物浓度,所得的主要药物动力学参数:门冬氨酸左氧氟沙星t1/2K a=7.461m in、t1/2α=16.499m in、t1/2β(m in)=218.989m in、tm ax=22.600m in、AUC=1202.262(μg.m in)/m l;盐酸左氧氟沙星t1/2K a=0.064m in、t1/2K e=24.155m in、tm ax=3.433m in、Cm ax=10.946μg/m l、AUC=420.925(μg.m in)/m l;乳酸左氧氟沙星t1/2K a=0.409m in、t1/2K e=13.576m in、tm ax=2.131m in、Cm ax=13.042μg/m l、AUC=282.797(μg.m in)/m l;左氧氟沙星t1/2K a=0.977m in、t1/2K e=8.519m in、tm ax=3.448m in、Cm ax=13.624μg/m l、AUC=221.667(μg.m in)/m l。结论门冬氨酸左氧氟沙星在大鼠体内的生物利用度比左氧氟沙星及其盐有所提高。     

病毒性脑膜脑炎262例血清线粒体天冬氨酸转氨酶同工酶变化的临床意义

目的　探讨病毒性脑膜脑炎 (病脑 )患儿血清线粒体天冬氨酸转氨酶同工酶 (m AST)变化及其临床意义。方法　应用全自动生化分析仪测定 2 62例病脑患儿和 12 1例健康儿童静脉血清中m AST、天冬氨酸转氨酶总活性 (t AST)活性 ,并计算m AST/t AST。结果　轻度病脑组血清m AST活性 15.50± 3 .91U/L ,中度组3 4 .79± 7.2 5U/L ,重度组 55.76± 11.3 3U/L ,正常对照组 7.93± 2 .80U/L ,各组间比较差异有显著性 (P均 <0 .0 5) ;m AST/t AST值 ,轻度患儿组 (3 6.76± 8.51) % ,中度患儿组 (47.63± 11.53 ) % ,重度患儿组 (61.81±7.3 3 ) % ,正常对照组 (2 5.2 6± 9.2 1) % ,各组间比较差异亦有显著性 (P均 <0 .0 5)。结论　测定血清m AST活性及m AST/t AST可作为判断小儿病脑病情及预后的指标之一     

大剂量何首乌醇提物致大鼠多脏器损伤研究

目的观察大剂量何首乌对大鼠主要脏器的损伤作用,暴露其可能的毒性作用。方法采用亚急性毒性试验,初步比较生何首乌和制何首乌不同提取物（20g生药／b）灌胃28天的毒性,观察肝脏病变频数;进一步对毒性较大的生何首乌和制何首乌醇提物进行研究,以40g生药／kg连续灌胃28天,观察大鼠体重增长情况、脏器指数变化、肝肾功能生化指标、组织病变结果。结果初步发现生何首乌和制何首乌醇提物毒性均大于各自的水提物和药材全粉,肉眼观察发现服药大鼠主要脏器中,肝脏发生显著病变的频数最高。何首乌醇提物毒性结果发现,与未给药动物比较,生何首乌组和制何首乌组大鼠体重增长显著受抑,生首乌组主要脏器指数显著升高;组织病理检查显示生何首乌组和制何首乌组肝、肾和肺脏均发生显著损伤;肝功能生化指标动态监测显示：生何首乌组谷丙转氨酶和谷草转氨酶仅在给药第3天时出现一过性显著升高,在此后第7、14、21和28天均无显著改变,而CCl。阳性对照组在实验第1周ATJT和AST即出现显著升高。结论初步实验提示何首乌的肝毒性物质可能集中在醇提物,其毒性器官主要集中在肝脏。进一步实验提示生何首乌毒性大于制何首乌,何首乌对肝、肾和肺均有损伤,其中对肺脏的损伤作用是首次报道;肝功能生化指标谷丙转氨酶和谷草转氨酶对何首乌肝损伤不敏感,提示何首乌肝损伤的机制可能与CCl。主要基于细胞膜脂质过氧化的肝损伤机制不同。     

虎杖苷对大鼠脑出血性损伤脑脊液中兴奋性氨基酸动态变化的影响

目的:观察虎杖苷对大鼠脑出血损伤后脑脊液中兴奋性氨基酸动态变化和脑组织含水量的影响,探讨虎杖苷对脑出血损伤的治疗作用及其作用机制。方法:采用微透析-高效液相色谱法建立天门冬氨酸(Asp)、谷氨酸(G lu)的测定方法;用Ⅶ型胶原酶诱导建立大鼠脑出血模型,观察虎杖苷对大鼠脑出血后0,6,12,24,36,48,60,72,84,96,108 h脑脊液内天门冬氨酸、谷氨酸含量的动态变化,并断头取脑检测脑组织含水量。结果:天门冬氨酸和谷氨酸含量在大鼠脑出血后24 h内迅速升高,并于24 h达到最高,随后逐渐开始降低。虎杖苷治疗后,天门冬氨酸和谷氨酸含量均上升缓慢,分别在12~72,6~84 h与同时段模型组比较有显著性差异(P0.01或P0.05),84,96 h后与同时段模型组相比无显著性差异。与假手术组比较,模型组脑含水量明显较高,虎杖苷组则明显降低(P0.01)。结论:虎杖苷能抑制脑出血后脑脊液中ASP,G lu含量升高,能明显抑制脑出血造成的脑水肿,表明虎杖苷抗脑出血损伤的作用机制可能与其抗脑出血后兴奋性氨基酸含量的升高有关。     

Hearing impairment and hypoxia ischaemic encephalopathy: Incidence and associated factors

Objective

To establish the local incidence of hearing loss in newborns with Hypoxic Ischaemic Encephalopathy (HIE) and to identify associated risk factors.

Astrocytes in the damaged brain: Molecular and cellular insights into their reactive response and healing potential

Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities.     

Two generation reproduction and teratogenicity studies of feeding cyadox in Wistar rats

To investigate the teratogenic potential and reproductive toxicity of cyadox, a growth promoting agent, Wistar rats (F₀) were fed with diets containing cyadox (0, 50, 150 and 2500 mg/kg) or olaquindox (150 mg/kg), approximately equivalent to cyadox 5, 15, 250 or olaquindox 15 mg/kg b.w./day across two generations. Half of the pregnant rats (F₀, F_1b) were subjected to caesarean section on gestational day 20 for teratogenic examination and the other half produced pups F_1a and F_2a, respectively. At the 250 mg/kg b.w./day cyadox group, body weights of F_1b pregnant rats and F_2a on day 21 after birth decreased; fetal body lengths and tail lengths decreased; the number of fetal resorptions increased significantly; litter weights, number of viable fetuses decreased; number of embryo resorptions increased significantly; number of liveborn F_1a, F_1b and F_2a decreased. No macroscopic or microscopic change of any significance was found in the reproductive organs. Significant increases in the incidence of cervial ribs or lumbar ribs in F_2a pups and significant increases of relative organ weight of testis and epididymis in F_1b were observed at the 250 mg/kg b.w./day cyadox group. The NOAEL for reproduction/development of cyadox for rats was estimated to be 150 mg/kg diet, which was equivalent to approximately 15 mg/kg b.w./day.     

One-year efficacy of tenofovir alafenamide in patients with chronic hepatitis B: An observational study

Non-inferior antiviral efficacy and better renal safety have been reported in chronic hepatitis B patients with tenofovir alafenamide (TAF) treatment. The experience in real-world clinical practice is limited.We aimed to explore the efficacy after 1-year TAF treatment.A total of 148 patients (42 HBeAg-positive and 106 HBeAg-negative) with TAF treatment ≥1 year were included. Virological suppression (<20 IU/mL or undetectable), HBsAg level, alanine aminotransferase (ALT) normalization (≤36 U/L), and estimated glomerular filtration rate (eGFR) were analyzed at 1 year. Multivariate logistic regression analysis was performed to determine the associated factors for virological suppression and ALT normalization.Virological suppression was achieved in 83% and the 1-year median decline of hepatitis B virus DNA was 5.18 log IU/mL. ALT normalization occurred in 75.7%. HBsAg level decreased at a median of 0.27 log IU/mL with significant difference from baseline (P < .001). Baseline ALT (odds ratio [OR] 1.005, 95% confidence interval [CI] 1.000–1.010, P = .036) and hepatitis B virus DNA (OR 0.222, 95% CI 0.079–0.621, P = .004) were significant factors for 1-year virological suppression. Age (OR 1.064, 95% CI 1.003–1.130, P = .041) was associated with ALT normalization. Significant changes were observed in creatinine (mean increase 0.03 mg/dL, P = .011) and eGFR (mean decrease 2.6 mL/min/1.73 m², P = .004) after 1-year TAF treatment.One-year TAF treatment came to good virological response, modest ALT normalization rate and significant HBsAg decline. The observation of significant changes in eGFR warranted further studies.