[Mode of median nerve irritation under different wrist forcing postures observed by ultrasonography and foot pressure measurement system].

Objective: To analyze the influence of simulation mouse use motion under different wrist forcing postures on median nerve, tendons and ligaments in the carpal tunnel. Methods: From June to November in 2017, a total of 49 healthy volunteers [aged from 18 to 27 years, 24 males (48 cases of hands) and 25 females (50 cases of hands)] were selected in the Institute of Digitized Medicine and First Affiliated Hospital of Wenzhou Medical University.Three hand postures of the volunteers were simultaneously and continuously measured by using LOGIQ E9 ultrasonic diagnostic apparatus and Zebris foot pressure distribution measurement system.Seventeen parameters of nerves, tendons and ligaments in carpal tunnel were observed under natural (0 N), and two forced (25 and 50 N) states.Double factor variance analysis was performed with generalized estimating equation (GEE). Results: With increasing pressure (0, 25 and 50 N) of hand postures, the distance between median nerve and transverse carpal ligament were all less than 0.2 cm.The differences in both the distance between median nerve and flexor pollicis longus under the hand pressure changes or under the hand posture changes and the top angle of a triangle composed of median nerve, flexor pollicis longus and flexor digitorum superficialis group under the hand pressure changes or under the hand posture changes were all significant under the GEE analysis (all P<0.01). There were no significant changes in all other structural parameters in the carpal tunnel with the increasing of hand pressure (all P>0.05). Conclusions: The influence of the transverse carpal ligament to the median nerve belongs to the mechanism of pressure-induced irritation damage.The influence of flexor pollicis longus to median nerve belongs to the mechanism of tension-induced irritation damage.The influence of flexor digitorum superficialis to median nerve belongs to the mechanism of mixed shear irritation damage.

Hydrogen peroxide regulated photosynthesis in C4-pepc transgenic rice.

In this study, we investigated the photosynthetic physiological basis in 'PC' transgenic rice (Oryza sativa L.), showing high-level expression of the gene encoding C4 phosphoenolpyruvate carboxylase (pepc), by hydrogen peroxide (H2O2). The C4-PEPC gene (pepc) from maize in the transgenic rice plants was checked by PCR. Comparison of yield components and photosynthetic indices between PC and untransformed wild-type (WT) plants indicated that increased yield in PC was associated with higher net photosynthetic rate and higher activities of phosphoenolpyruvate carboxylase (PEPC). Both PC and WT plants were treated with 1 mmol L(-1) abscisic acid (ABA), 0.04% 1-butanol (BA), 2 mmol L(-1) neomycin (NS), or 2 mmol L(-1) diphenyleneiodonium chloride (DPI) to investigate the relationship between photosynthesis and levels of H2O2 and phosphatidic acid. In both PC and WT, ABA induced H2O2 generation and simultaneous decrease in stomatal conductance (g(s)). PC plants treated with BA showed decreased H2O2 content and strongly increased g(s) within 2 h of treatment. Similar results were observed in response to DPI treatment in PC. However, WT did not observe the decrease of H2O2 during the treatments of BA and DPI. The reduced H2O2 content in PC caused by BA treatment differed to that induced by DPI because BA did not inhibit NADPH oxidase activities. While BA induced a larger PEPC activity in PC, and higher catalase activity as well. These results indicated that the regulation of endogenous H2O2 metabolism of PC could be helpful for enhancing photosynthetic capability.

Effect of soluble soybean protein hydrolysate-calcium complexes on calcium uptake by Caco-2 cells.

Soybean protein hydrolysates (SPHs) bind with calcium, forming soluble SPH-calcium complexes via the carboxyl groups of glutamic and aspartic acid residues. However, their effect on calcium uptake is still unclear. In this study, Caco-2 cells were used to estimate the effect of SPH-calcium complexes with different molecular weights on calcium uptake in vitro. The changes in intracellular calcium ion concentration were measured by Fura-2 loading and expressed in fluorescence intensity. SPH-calcium complexes could promote calcium uptake. Improved fluorescence intensity was significantly different in SPH-calcium complexes (10 to 30 kDa), SPH-calcium complexes (3 to 10 kDa), and SPH-calcium complexes (1 to 3 kDa). The maximum levels of relative fluorescence intensity (18.3) occurred with SPH-calcium complexes (10 to 30 kDa). The effect of SPH-calcium complexes (10 to 30 kDa) on Ca(2+) increase was determined to be concentration dependent in the range of 0.5 to 4 mg/mL. Our results indicate that soybean protein itself might be responsible for promoting calcium absorption.

A study of the soluble complexes formed during calcium binding by soybean protein hydrolysates.

The soluble complexes formed between hydrolyzed soybean protein and calcium at pH 7.4 were investigated using dialysis, gel chromatography, and Fourier transform infrared spectrometry (FTIR). The results demonstrate that the amount of calcium bound was significantly different for soybean protein hydrolysates obtained using the proteases neutrase, flavourzyme, protease M, and pepsin. Maximum levels of calcium binding (66.9 mg/g) occurred with hydrolysates produced using protease M. Peptide fragments exhibiting high calcium binding capacity had molecular weights of either 14.4 kDa or 8 to 9 kDa, and the calcium binding capacity was linearly correlated with carboxyl group content (R(2)= 0.8204). FTIR experiments revealed that upon binding calcium, the amide I band underwent a shift to lower wave numbers. A wide, intense Ca-O absorption band also appeared between 400 and 100 cm(-1) in the far-infrared spectrum. The width and intensity of this band increased after treatment of samples with glutaminase. The amount of bound calcium was related to both the molecular weight of the peptides and to the carboxyl group content, and the most likely sites for calcium binding are the carboxyl groups of Asp and Glu.