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The pH-responsive hydrogels were obtained through successive carboxymethylation and phosphorylase elongatation of phytoglycogen and their structure and functional characterizations were investigated. Phytoglycogen (PG) was first carboxymethylated to obtain carboxymethyl phytoglycogen (CM-PG) with degree of substitution (DS) at 0.15, 0.25, 0.30, and 0.40, respectively. Iodine staining and X-ray diffraction analysis suggested that the linear glucan chains were successfully phosphorylase-elongated from the non-reducing ends at the CM-PG surface and assembled into the double helical segments, leading to formation of the hydrogel. The DS of CM-PG significantly influenced elongation of glucan chains. Specifically, fewer glucan chains were elongated for CM-PG with higher DS and the final glucan chains were shorter, resulting in lower gelation rate of chain-elongated CM-PG and lower firmness of the corresponding hydrogels. Scanning electron microscope observed that the hydrogels exhibited a porous and interconnected morphology. The swelling ratio and volume of hydrogels was low at pH 3–5 and then became larger at pH 6–8 due to electrostatic repulsion resulting from deprotonated carboxymethyl groups. Particularly, the hydrogel prepared from chain-elongated CM-PG (DS = 0.25) showed the highest sensitivity to pH. These results suggested that phosphorylase-treated CM-PG formed the pH-responsive hydrogel and that the elongation degree and the properties of hydrogels depended on the carboxymethylation degree. Thus, it was inferred that these hydrogels was a potential carrier system of bioactive substances for their targeted releasing in small intestine.

SUMMARY: The nerve entry points (NEPs) cannot yet be accurately localized for the treatment of thigh adductor muscles spasticity in chemical neurolysis. The aim of this study was to identify the location and depth of the NEPs of thigh adductor muscles by spiral computed tomography (CT) and bony landmarks. Forty lower limbs of twenty adult cadavers were dissected in supine position. A curved line on skin surface from the tip of greater trochanter of femur to the center of pubic tubercle was designated as the horizontal reference line (H). Another curved line from the tip of great trochanter to the lateral epicondyle of femur was designated as the longitudinal reference line (L). Following dissection, the NEPs were labeled with barium sulfate, and their body surface projection points (P) were determined by spiral CT. Projection of NEP in the opposite direction was designated as P'. The percentage location of the intersections (PH and PL) of P with the H and L and the percentage depth of NEPs were determined with the Syngo system. The PH for the NEP of pectineus, gracilis, adductor longus, adductor brevis and adductor magnus muscles branch were located at 76.41±0.71 %, 93.85±2.07 %, 92.05±2.15 %, 80.75±1.20 % and 88.08±1.09 % of the H, respectively. The PLwere at 1.64±0.04 %, 29.89±1.90 %, 16.06±1.32 %, 11.66±0.11 % and 22.94±0.90 % of the L, respectively. The depth of NEP from P points were at 17.52±0.52 %, 38.38±2.75 %, 20.88±0.79 %, 20.35±0.82 % and 39.52±0.67 % of PP', respectively. These results help to carry out more precise localization of the NEPs. It should provide a novel anatomical guide for improving the efficacy and efficiency of chemical neurolysis in treating thigh adductor muscle spasticity. RESUMEN: Aún no se pueden localizar con precisión los puntos de entrada del nervio (PEN) para el tratamiento de la espasticidad de los músculos aductores del muslo a través de la neurólisis química. El objetivo de este estudio fue identificar la ubicación y la profundidad de los PEN de los músculos aductores del muslo mediante tomografía computarizada espiral (TC) y puntos de referencia óseos. Se disecaron loa miembros inferiores de 20 cadáveres adultos en posición supina. Se trazó una línea curva en la superficie de la piel desdeel ápice del trocánter mayor del fémur hasta el centro del tubérculo púbico y se designó como línea de referencia horizontal (H). Otra línea curva desde el ápice del trocánter mayor hasta el epicóndilo lateral del fémur se designó como línea de referencia longitudinal (L). Después de la disección, los PEN se marcaron con sulfato de bario y sus puntos de proyección de la superficie del cuerpo (P) se determinaron mediante TC helicoidal. La proyección de PEN en la dirección opuesta se designó como P '. El porcentaje de ubicación de las intersecciones (PH y PL) de P con H y L y la profundidad porcentual de los PEN se determinaron con el sistema Syngo. Los PH para los PEN de los músculos pectineus, gracilis, adductor longus, aductor brevis y rama aductora del músculo aductor magnus se localizaron en 76,41±0,71 %, 93,85±2,07 %, 92,05±2,15 %, 80,75±1,20 % y 88,08±1,09 % de H, respectivamente. Los PL estuvieron en 1,64±0,04 %, 29,89±1,90 %, 16,06±1,32 %, 11,66±0,11 % y 22,94±0,90 % de la L, respectivamente. La profundidad de PEN de P puntos fue de 17,52±0,52 %, 38,38±2,75 %, 20,88±0,79 %, 20,35±0,82 % y 39,52±0,67 % de PP ', respectivamente. Estos resultados ayudan a realizar una localización más precisa de los PEN. Se debe proponer una nueva guía anatómica para mejorar la eficacia y la eficiencia de la neurólisis química en el tratamiento de la espasticidad del músculo aductor del muslo.

As a recyclable natural material, starch is an important raw material in food and other fields. The native starch by esterification could improve the performance of the original starch and expand its range of application. This article reviews the preparation process of acetylated distarch adipate, starch sodium octenylsuccinate, starch acetate, hydroxypropyl starch, and starch phosphate and research into the influence of starch esters on dough. At the same time, it forecasts the trend of starch esters and application prospect in the future research.

In this paper, the problem of global stabilization with the developed control Lyapunov function V has been considered. Some sufficient conditions of global stabilization are presented when V is negative semi-definite, hence effectively extending the realm of application of control Lyapunov function. Some examples are presented to show that the results of the paper are useful in stabilization of nonlinear system.