Correlation of acetylcholinesterase activity in the brain and blood of wistar rats acutely infected with Trypanosoma congolense

ObjectiveTo investigate the neurotransmitter enzyme Acetylcholinesterase (AChE) activity in the brain and blood of rats infected with Trypanosoma congolense (T. congo).MethodsPresence and degree of parasitemia was determined daily for each rat by the rapid matching method. AChE activity was determined by preparing a reaction mixture of brain homogenate and whole blood with 5, 5-dithiobisnitrobenzioc acid (DTNB or Ellman's reagent) and Acetylthiocholine (ATC). The increase in absorbance was recorded at 436 nm over 10 min at 2 min intervals. Trypanosome species identification (before inoculation and on day 10 post infection) was done by Polymerase chain reaction using specific primers.ResultsThe AChE activity in the brain and blood decreased significantly as compared with the uninfected control. The AChE activity dropped to 0.32 from 2.20 μmol ACTC min^?1mg protein^?1 in the brain and 4.57 to 0.76 μmol ACTC min-1mg protein^?1 in the blood. The animals treated with Diminaveto at 3.5 mg/kg/d were observed to have recovered significantly from parasitemia and were able to regain AChE activity in the blood but not in the brain as compared to the control groups. We also observed, that progressive parasitemia resulted to alterations in PCV, Hb, RBC, WBC, neurophils, total protein, lymphocytes, monocytes and eosinophil in acute infections of T. congo. Polymerase chain reaction (PCR) of infected blood before inoculation and on day 10 post infection revealed 600 bp on agarose gel electrophoresis.ConclusionsThis finding suggest that decrease in AChE activity increases acetylcholine concentration in the synaptic cleft resulting to neurological failures in impulse transfer in T. congo infection rats.     

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with N^G-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.     

神经调节素对阿尔茨海默病大鼠模型海马细胞凋亡和核转录因子κB表达的影响

目的 研究神经调节素1β( neuregulin 1β,NRG1β)对β-淀粉样蛋白1-40(beta-amyloid protein,Aβ1-40)所致的模拟阿尔茨海默病模型大鼠空间学习记忆能力、神经元凋亡、核转录因子κB( nuclear factor kappa B,NFκB)表达的影响,探讨NRG改善学习记忆能力的作用机制.方法 成年健康雄性Wistar 大鼠30只,随机数字表法分为对照组、模型组和治疗组,每组10只,经侧脑室微量注射Aβ1-40建立实验性阿尔茨海默病模型大鼠,经侧脑室注射NRG1β(0.3μg·kg-1)干预治疗.各组大鼠实验前及造模7d后、治疗14d后均用Y型迷宫检测大鼠学习和记忆功能,利用HE染色观察海马神经细胞的结构变化,原位TUNEL法检测海马神经细胞凋亡,免疫组织化学法检测海马神经细胞NFκB的表达.结果 模型组大鼠学习能力[ (57.50±1.58)次]和记忆能力[(7.20±1.03)次]较对照组学习[(59.50±2.79)次]和记忆能力[(7.50±1.08)次]明显下降(=20.36,5.28,P＜0.05),海马区神经细胞排列稀疏、紊乱,有明显神经元脱失,TUNEL阳性细胞数明显增多、NFκB表达增加(P＜0.05).NRG1β治疗组大鼠学习记忆能力[ (67.70±4.90)次,(5.80±0.63)次]及细胞结构较模型组[(79.10±4.12)次,(4.40±0.69)次]显著改善( t=5.63,4.69,P＜0.05).相对于模型组[(41.10±7.95)次,(29.30±7.24)个],NRG1β治疗组NFκB表达(25.90±6.67)明显减弱、细胞凋亡数量[(23.50±3.89)个]明显减少(t=4.63,2.23,P＜0.05).结论 NRG1β能抑制海马神经细胞NFκB表达,减少细胞凋亡,从而改善阿尔茨海默病大鼠的学习和记忆能力.     

Respiratory symptoms in preterm infants: burden of disease in the first year of life

Objective

While respiratory symptoms in the first year of life are relatively well described for term infants, data for preterm infants are scarce. We aimed to describe the burden of respiratory disease in a group of preterm infants with and without bronchopulmonary dysplasia (BPD) and to assess the association of respiratory symptoms with perinatal, genetic and environmental risk factors.

Methods

Single centre birth cohort study: prospective recording of perinatal risk factors and retrospective assessment of respiratory symptoms during the first year of life by standardised questionnaires. Main outcome measures: Cough and wheeze (common symptoms), re-hospitalisation and need for inhalation therapy (severe outcomes). Patients: 126 preterms (median gestational age 28.7 weeks; 78 with, 48 without BPD) hospitalised at the University Children''s Hospital of Bern, Switzerland 1999-2006.

Results

Cough occurred in 80%, wheeze in 44%, rehospitalisation in 25% and long term inhalation therapy in wheezers in 13% of the preterm infants. Using logistic regression, the main risk factor for common symptoms was frequent contact with other children. Severe outcomes were associated with maximal peak inspiratory pressure, arterial cord blood pH, APGAR and CRIB-Score.

Conclusions

Cough in preterm infants is as common as in term infants, whereas wheeze, inhalation therapy and re-hospitalisations occur more often. Severe outcomes are associated with perinatal risk factors. Preterm infants who did not qualify for BPD according to latest guidelines also showed a significant burden of respiratory disease in the first year of life.     

Neonatal airway obstruction caused by rapidly growing nasopharyngeal teratoma

A case report is presented of a rapidly growing congenital nasopharyngeal teratoma (epignathus) in a preterm infant, leading to severe upper airway obstruction. Prenatal diagnosis by ultrasonography did not reveal the condition because the tumour masses were initially small and there was no polyhydramnios. Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period and should be treated surgically.
Conclusion:  Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period.     

Core-peripheral temperature gradient in children: does it reflect clinically important changes in circulatory haemodynamics?

Following open heart surgery, changes in core and peripheral skin temperature and changes in the core-peripheral temperature gradient were measured in 10 children. These were correlated with changes in cardiac index, systemic vascular resistance index, mean arterial pressure and urinary output. During the study intervals, which lasted 1 h each, no changes in medical management were made. Using Spearman's rank correlation, only a change in central venous pressure was found to correlate with a change in the core-peripheral temperature gradient. We conclude that a change in the core-peripheral temperature will give valuable information about the patient's intravascular volume.