ObjectiveTo explore a new method for establishing premature piglet model of short bowel syndrome. MethodsThirty two premature piglets were randomly divided into 4 groups, including jejunoileal anastomosis group, jejunocolic anastomosis group, sham operation group, and blank control group. Each group enrolled 8 premature piglets. Jejunoileal anastomosis group:resected 75% of small intestinal, reserved the proximal jejunum (10% of the total small intestine length) and distal ileum (15% of the total small intestine length), with jejunoileal anastomosis. Jejunocolic anastomosis group:removed 75% of the small intestine, including the distal jejunum (25% of the total small intestine length), total ileum (50% of total small intestine length), the ileocecal valve, and the colon beyond 5 cm far from the ileocecal valve, retained the proximal jejunum (25% of the total length of the small intestine), with jejunocolic anastomosis. Sham group:cut off the ileum at a distance of nearly 25 cm of the ileocecal valve ileum, then anastomosed the intestine again. Blank control group:no surgery. Data included the first defecation time, duration of diarrhea and parenteral nutrition (PN) after surgery, the length and weight of the small intestine, the weight of the colon, the villus height and crypt depth of both jejunum and ileum at 21st days postoperatively, were collected and analysed. ResultsCompared with the sham group and blank control group, jejunoileal and jejunocolic anastomosis groups showed higher villus height and the crypt depth of jejunum and ileum (P<0.050), provided enough anatomy evidence of intestinal adaptation. However, the duration of PN in jejunocolic group was longer than in jejunoilea anastomosis group (P<0.050). The length and weight of the small intestine and the weight of colon in jejunocolic anastomosis group, were lower than in jejunoileal anastomosis group (P<0.050), improving that the ability of intestinal adaptation of jejunocolic anastomosis was better than the jejunoileal anastomosis group. ConclusionsPremature piglet models of short bowel syndrome could be established by methods of jejunoileal and jejunocolic anastomosis. Both of the methods had their own different degree of intestinal adaptation and growth. The jejunoileal anastomosis is maybe a better way to establish this model.
The study of neuronal activity with low frequency has shown an increasing interest for its greater stability and reliability recent years. One challenge in analyzing this kind of activity is to find similarities and differences between signals efficiently and effectively. The traditional analysis methods, such as short-time Fourier transform, are easily obscured by background noises and often involve a large number of parameters. Therefore, this paper introduces a novel time-frequency analysis method based on wavelet transformation and half-ellipsoid modeling to extract instantaneous frequency and instantaneous phase information. This method overcomes some shortcomings of conventional time-frequency analysis. In this method, wavelet transformation is used to provide high-level representations of raw signals, and parsimonious half-ellipsoid models are used to extract changes in time domain and frequency domain of neural recordings. The method was validated to local field potentials (LFPs) of olfactory bulb of anesthetized rats during three different odor stimuli. The results suggested that this method could detect odor-relevant features from olfactory signals with large variability. The Odors then were classified with support vector machine (SVM) algorithm and the classification accuracy reached 79.4%.