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71.
Yan Xue Liu Jia Wu Ke-Xin Yang Nan Pan Li-Ben Song Ying Liu Yang Tang Zhong-Hua 《Journal of Plant Growth Regulation》2022,41(6):2421-2434
Journal of Plant Growth Regulation - Early-spring plants are a special type of plant that complete their life cycle promptly in cold, early spring. Very little effort has been made into researching... 相似文献
72.
Ying Jin Dan Long Juan Li Ruichao Yu Yueming Song Jie Fang Xi Yang Shu Zhou Shishu Huang Zhihe Zhao 《Journal of cellular physiology》2019,234(9):14838-14851
Bone and tooth, fundamental parts of the craniofacial skeleton, are anatomically and developmentally interconnected structures. Notably, pathological processes in these tissues underwent together and progressed in multilevels. Extracellular vesicles (EVs) are cell-released small organelles and transfer proteins and genetic information into cells and tissues. Although EVs have been identified in bone and tooth, particularly EVs have been identified in the bone formation and resorption, the concrete roles of EVs in bone and tooth development and diseases remain elusive. As such, we review the recent progress of EVs in bone and tooth to highlight the novel findings of EVs in cellular communication, tissue homeostasis, and interventions. This will enhance our comprehension on the skeletal biology and shed new light on the modulation of skeletal disorders and the potential of genetic treatment. 相似文献
73.
Chien-Hung Liu Wen-Ming Chen Jo-Shu Chang 《World journal of microbiology & biotechnology》2007,23(5):633-640
Acidic lipase finds its commercial values in medical applications and bioremediation of food wastes. In this work, approaches
for rapid screening of lipase-producing bacteria were developed and the feasibility assessment of the screening methods was
performed. From food waste samples, the proposed screening procedures allowed isolation of sixteen pure bacterial strains
expressing higher lipase activity at acidic pH (pH 6.0) than at alkaline pH (pH 9.0). To enhance the accuracy of lipase activity
determination under acidic conditions, a novel assay procedure was also developed by deactivating lipase activity by microwave
treatment prior to back titration. This additional step could minimize interferences arising from residual lipase activity
during conventional direct back-titration methods in measuring lipase activity at acidic pH. Using the four strategies proposed
in this work, the best acidic-lipase-producing isolate was obtained by strategy C (SSC) and was identified as Aeromonas sp. C14, displaying an optimal lipase activity of 0.7 U/ml at an acidic pH of 6.0. 相似文献
74.
The occurrence of Nyctereutes during the Plio-Pleistocene has long been reported in northern China, with the highest abundance in the Nihewan Basin. However, due to site dispersal, the coexistence of different taxa, and lack of a precise stratigraphic constraint, the evolutionary process of this genus remains enigmatic. In this study, we re-examined the available Nyctereutes materials recovered from the Nihewan Basin housed in IVPP and Tianjin Natural History Museum, in addition to a newly recovered specimen from our latest excavation. Furthermore, we compared these materials with Nyctereutes fossils recovered from the Pleistocene Zhoukoudian sites near Beijing and the extant species N. procyonoides. Our analysis of the upper molar morphometry reveals the variations in size and dietary characteristics within different species of Nyctereutes during the late Plio-Pleistocene. The examination of molars indicates an increase in the size of Nyctereutes sinensis compared to early Pliocene N. tingi as well as changes in the molar teeth morphology. Subsequently, changes in diet or environmental factors possibly caused the decrease of body size in the late Pleistocene. We also estimate an age constraint for the fossils of N. sinensis from the Xiashagou section by relocating Licent's localities and referring of updated magnetostratigraphic data. 相似文献
75.
The phorbol myristate acetate (PMA) stimulated nutrophil respiratory burst has been considered to simply involve the activation of protein kinase C (PKC). However, the PLD activity was also increased by 10‐fold in human neutrophils stimulated with 100 nM PMA. Unexpectedly, U73122, an inhibitor of phospholipase C, was found to significantly inhibit PMA‐stimulated respiratory burst in human neutrophils. U73122 at the concentrations, which were sufficient to inhibit the respiratory burst completely, caused partial inhibition of the PLD activity but no inhibition on PKC translocation and activation, suggesting that PLD activity is also required in PMA‐stimulated respiratory burst. Using 1‐butanol, a PLD substrate, to block phosphatidic acid (PA) generation, the PMA‐stimulated neutrophil respiratory burst was also partially inhibited, further indicating that PLD activation, possibly its hydrolytic product PA and diacylglycerol (DAG), is involved in PMA‐stimulated respiratory burst. Since GF109203X, an inhibitor of PKC that could completely inhibit the respiratory burst in PMA‐stimulated neutrophils, also caused certain suppression of PLD activation, it may suggest that PLD activation in PMA‐stimulated neutrophils might be, to some extent, PKC dependent. To further study whether PLD contributes to the PMA stimulated respiratory burst through itself or its hydrolytic product, 1,2‐dioctanoyl‐sn‐glycerol, an analogue of DAG , was used to prime cells at low concentration, and it reversed the inhibition of PMA‐stimulated respiratory burst by U73122. The results indicate that U73122 may act as an inhibitor of PLD, and PLD activation is required in PMA‐stimulated respiratory burst. 相似文献
76.
J.-Y. Roh H.-W. Park Y.-H. Je D.-W. Lee B.-R. Jin H.-W. Oh S. S. Gill & S.-K. Kang 《Letters in applied microbiology》1997,24(6):451-454
Bacillus thuringiensis NTB-1 isolated from soil samples in Korea produces ovoidal parasporal inclusions with proteins of approximately 24–40 kDa in size. Although serological study indicated that the isolate has a flagella (H) antigen identical with subsp. israelensis , it seemed to be non-insecticidal against Lepidoptera and Coleoptera as well as Diptera. To investigate the activity of non-insecticidal B. thuringiensis transformed with insecticidal crystal protein genes, cryIVD and cytA genes of B. thuringiensis subsp. morrisoni PG-14, highly toxic to mosquito larvae, were introduced into the isolate NTB-1. The expression of mosquitocidal crystal protein genes in NTB-1 was characterized by SDS–PAGE analysis and electron microscopy. The results showed that crystalline inclusions of host, CryIVD and CytA were stably expressed in the transformant. However, the mosquitocidal activity of transformant was similar to that of B. thuringiensis subsp. kurstaki Cry− B harbouring cryIVD and cytA genes, demonstrating that a synergistic effect by an interaction of both introduced insecticidal and resident non-insecticidal crystal proteins was not observed. 相似文献
77.
Il-Young Paik Hwa-Eun Jin Ah-Ram Suh Hee-Tae Roh Sang-Hoon Suh 《Biochemical and biophysical research communications》2009,383(1):103-107
To investigate the effects of hydration status on oxidative DNA damage and exercise performance, 10 subjects ran on a treadmill until exhaustion at 80% VO2max during four different trials [control (C), 3% dehydration (D), 3% dehydration + water (W) or 3% dehydration + sports drink (S)]. Dehydration significantly decreased exercise time to exhaustion (D < C and S). Plasma MDA levels were significantly higher at pre-exercise in D than C. Plasma TAS was significantly lower at pre-exercise in C and S than in D, and was significantly lower in S than D at 60 min of recovery. Dehydration significantly increased oxidative DNA damage during exercise, but fluid replacement with water or sports drink alleviated it equally. These results suggest that (1) dehydration impairs exercise performance and increases DNA damage during exercise to exhaustion; and (2) fluid replacement prolongs exercise endurance and attenuates DNA damage. 相似文献
78.
Corticosterone, the major stress hormone, plays an important role in regulating neuronal functions of the limbic system, although the cellular targets and molecular mechanisms of corticosteroid signaling are largely unknown. Here we show that a short treatment of corticosterone significantly increases α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-mediated synaptic transmission and AMPAR membrane trafficking in pyramidal neurons of prefrontal cortex, a key region involved in cognition and emotion. This enhancing effect of corticosterone is through a mechanism dependent on Rab4, the small GTPase-controlling receptor recycling between early endosome and plasma membrane. Guanosine nucleotide dissociation inhibitor (GDI), which regulates the cycle of Rab proteins between membrane and cytosol, forms an increased complex with Rab4 after corticosterone treatment. Corticosterone also triggers an increased GDI phosphorylation at Ser-213 by the serum- and glucocorticoid-inducible kinase (SGK). Moreover, AMPAR synaptic currents and surface expression and their regulation by corticosterone are altered by mutating Ser-213 on GDI. These results suggest that corticosterone, via SGK phosphorylation of GDI at Ser-213, increases the formation of GDI-Rab4 complex, facilitating the functional cycle of Rab4 and Rab4-mediated recycling of AMPARs to the synaptic membrane. It provides a potential mechanism underlying the role of corticosteroid stress hormone in up-regulating excitatory synaptic efficacy in cortical neurons. 相似文献
79.
80.