ABSTRACT
<p><b>OBJECTIVE</b>To study the extraction system of hirudin emulsion liquid membrane with the Poecilobdella manillensis as raw material, di-(2-ethylhexyl) phosphate (D2EHPA) as carrier, Span 80 as emulsifier, octane and D2EHPA mixed to constitute membrane solution, diluted HCl solutions as internal aqueous phase.</p><p><b>METHOD</b>Using the orthogonal experiment to optimize the extraction conditions of hirudin reference substance such as membrane phase, internal aqueous phase volume ratio (MIPVR), external aqueous phase pH, internal aqueous phase pH, mobile carrier concentration and so on, and then using hirudin crude extracts to do purifying experiment, and gaining experimental samples.</p><p><b>RESULT</b>The optimal conditions of hirudin extraction were as follows: MIPVR 10: 3, internal aqueous phase pH 2.6, external aqueous phase pH 3.4, the mass fraction of carrier D2EHPA 2%. In the optimal extraction conditions, when the initial concentration of hirudin was one anti-thrombin activity units (ATU) x mL(-1), ATU recovery rate of the reference substance was 83.06%. In the purifying experiment of crude extracts, ATU recovery rate was 82.99%, and the specific activity of sample was 3 289.48 the ATU x mg(-1). Discontinuous polyacrylamide gel electrophoresis and spectral scanning, the results showed that the purity and reference substance were considerable.</p><p><b>CONCLUSION</b>The method of preparation hirudin was relatively simple, the purity of the experimental samples and ATU recovery were both high.</p>
Subject(s)
Animals , Emulsions , Chemistry , Hirudins , Leeches , Chemistry , Membranes, Artificial , Solid Phase Extraction , MethodsABSTRACT
Mouse stroke models provide experiment basis for study of the mechanisms of cell death and neural repair, and the neuroprotective effect of new drugs. There are at least three models of middle cerebral artery occlusion (MCAO) routinely used in experimental study. These models vary widely in their application in study of cell death or neural repair, and simulation of human diseases. This review article is focused on the characteristics of three mouse MCAO models and the strains-related differences in susceptibility to cerebral ischemia.
Subject(s)
Animals , Mice , Brain Ischemia , Disease Models, Animal , Infarction, Middle Cerebral Artery , Classification , Species Specificity , StrokeABSTRACT
A new experimental software of an X-ray machine's console virtual operation system based on VB is introduced. This software can simulate the manual operation on the X-ray machine's console, and has the characteristics of easy operation, multi-function and good interactivity.
Subject(s)
Computer Simulation , Software Design , Tomography, X-Ray Computed , Methods , User-Computer InterfaceABSTRACT
Chronic post-hypoxic myoclonus, also known as Lance-Adams syndrome (LAS), is a rare complication of successful cardiopulmanry resuscitation often accompanied by action myoclonus and cerebellar ataxia. It is seen in patients who have undergone a cardiorespiratory arrest, regained consciousness afterwards, and then developed myoclonus days or weeks after the event. Worldwide, 122 cases have been reported in the literature so far, including 1 case of Chinese. Here we report 2 Chinese LAS patients with detailed neuroimagings. Cranial single photon emission computed tomography (SPECT) of patient 1, a 52-year-old woman, showed a mild hypoperfusion in her left temporal lobe, whereas patient 2, a 54-year-old woman, manifested a mild bilateral decrease of glucose metabolism in the frontal lobes and a mild to moderate decrease of the N-acetyl aspartate (NAA) peak in the bilateral hippocampi by cranial [(18)F]-fluorodeoxyglucose positron emission tomographic (PET) scan and cranial magnetic resonance spectroscopy (MRS), respectively. We also review the literature on the neuroimaging, pathogenesis, and treatment of LAS.