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1. The present study is designed to investigate the brain distribution and plasma pharmacokinetics profiles of chlorogenic acid (CGA) after intranasal administration in Charles–Foster rats to evaluate whether the CGA molecules are transported directly via the nose-to-brain path.

2. The CGA is administered intravenously (IV) and intranasally (IN) at the dose of 10?mg/kg. Further, its concentration in the plasma, cerebrospinal fluid (CSF) and the whole brain is analyzed by HPLC-UV method.

3. The study observes that CGA is rapidly absorbed in plasma with tmax of 1?min similar to IV route after IN administration. The peak plasma concentration and AUC0–24 are higher by 3.5 and 4.0 times respectively in IV administration, compared to IN delivery that represents the significant less systemic exposure of CGA in IN route.

4. However, the concentration of CGA in the brain is 4, 6.5, 5.3, 5.2 and 4.5 times higher at 30, 60, 120, 240 and 360?min, respectively in IN administration compared to IV administration. The exposure of CGA in the brain after IN administration (AUCbrain, IN) was significantly greater (4 times) as compared to the exposure of CGA in the brain (AUCbrain, IV) after IV administration reflecting significant brain uptake of CGA through nasal route. Therefore, IN delivery of CGA can be a promising approach for the treatment of stroke and neurodegenerative disorders.  相似文献   

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A two and half year old male child was seen with systemic hypertension, left ventricular dysfunction, mitral regurgitation and congestive cardiac failure. Examination revealed adenoid hypertrophy. He was also suffering from obstructive sleep apnea. He was being treated with anti-hypertensive and anti-failure drugs. Adenoidectomy was performed following which obstructive sleep apnea symptoms disappeared and his cardiac status improved markedly. Subsequently he was weaned off anti-hypertensive and anti-failure therapy.  相似文献   
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Pulmonary function in healthy young adult Indians in Madras.   总被引:2,自引:0,他引:2       下载免费PDF全文
Forced vital capacity, forced expiratory volume in one second, functional residual capacity, residual volume, total lung capacity, and single breath diffusing capacity measurements (effective alveolar volume, carbon monoxide transfer factor, and transfer coefficient) were measured in 247 young healthy adults (130 male, 117 female) aged 15-40 years living in Madras. Subjects were of Dravidian stock, living at sea level with rice as their staple diet. Regression equations were derived for men and women for predicting normal pulmonary function for young adults in South India. The values were similar to those reported for subjects from Western India and lower than those reported for North Indians and caucasians.  相似文献   
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Headache following lumbar puncture is a well known and well described complication. Various manoeuvres have been tried to prevent post lumbar puncture headache--the commonest being bed rest for 4 to 24 hours following lumbar puncture, though its value is questionable. Randomised controlled clinical trial was done to evaluate the effect of 24 hours bed rest on the incidence and severity of post lumbar puncture headaches. Two hundred and eight patients were randomly allocated to either the ambulant or the bed rest group. Patients were interviewed by a single investigator on days 0, 1, 2 and 7 about the presence and nature of headache. Other relevant clinical and laboratory data pertaining to the lumbar puncture was collected. The overall incidence of post lumbar puncture headache was 17%; 15% in the ambulant and 18% in the bed rest group. Of the patients who had headaches, severe headache was observed in 57% in the ambulant and 12% in the bed rest group (p = 0.02). Other variables did not alter the outcome of headaches. Bed rest does not appear to alter the incidence of post lumbar puncture headaches, but reduces the severity in those who get headaches, after a lumbar puncture.  相似文献   
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A series of polycaprolactone and ternary-based (Na(2)O)(0.55-x)(CaO)(x)(P(2)O(5))(0.45) glass composites were created, each containing 20% volume percentage of glass with various calcium compositions. A short-term degradation study was carried out to investigate the physical and ion release behaviour of these composites, utilising analytical techniques such as dynamical mechanical analysis, and ion chromatography. All the composites experienced significant loss of weight and stiffness throughout the study, with the 24 mol% calcium composites losing the greatest amount of weight and stiffness. The pH profile of the aqueous solutions in which the composites were placed were initially acidic, but began to neutralise mid-way through the study, with the 36 mol% solution achieving the most acidic conditions. The ion release behaviour mirrored the mass loss behaviour of the glass component of the composites. The cations (sodium and calcium ions) release was comparable with the initial stages of composite mass degradation, both of which exhibited almost immediate release when placed into solution. The 24 mol% composites underwent rapid rates of cation release, while the 36 mol% experienced the slowest rates of release. By contrast, anion (phosphates and polyphosphates) release showed a dissimilar trend, with rapid release of the P(2)O(7) and P(3)O(10) occurring during the first few hours in solution, whilst the P(3)O(9) structure released steadily during the first 48 h in solution. Finally, PO(4) release was at a constant rate over the duration of the study, releasing up to 300 ppm from the 32 and 36 mol% samples by the end of 200 h. To summarise, these results show that by combining phosphate glasses with biodegradable polymer, it is possible to create composites whose rate of degradation can be controlled to meet the needs of their end application.  相似文献   
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Our inability to associate distant regulatory elements with the genes they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries, we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBSs), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes they regulate. A total of 2116 and 1942 CBSs >200 kb were assembled for HMC and HMF, respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBSs, we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a gene's regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide an extensive data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.  相似文献   
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