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51.
This study investigated the effect of type‐I interferon (IFN) on the expression of matrix metalloproteinases (MMPs) of the bovine endometrial stromal cells (BES) and epithelial cells (BEE). The cells were separated and purified from the caruncles and cultured in DMEM/F‐12 containing 10% fetal bovine serum. Spheroids were generated by using ascorbate. Zymograms of the supernatant showed that BEE predominantly expressed MMP‐9, whereas MMP‐2 was expressed in BES and homo‐spheroids. While MMPs expression was not detected in hetero‐spheroids. Real‐time quantitative PCR revealed that type‐I IFN and P4 suppressed the gene expression of MMP‐2 and MMP‐9 in hetero‐spheroids, respectively. On the other hand, gelatin zymography analysis of the supernatant showed that type‐I IFN strongly promote the clearance of MMPs. While zymograms of the MMPs stocked in the hetero‐spheroids were significantly reduced by type‐I IFN. Phenylmethanesulfonyl fluoride and leupeptin (both are serine proteinase inhibitors) significantly repressed the clearance of MMP‐2 and MMP‐9 induced by type‐I IFN. Moreover, collagen fibers in hetero‐spheroids significantly decreased after the treatment with type‐I IFN. In conclusion, it was suggested that type‐I IFN participate in the tissue remodeling by regulation the clearance of MMPs.  相似文献   
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Knowing the structure and variations of the plexus brachialis is important in neck and shoulder surgery. The knowledge of the brachial plexus reduces the injury rate of the nerves in surgical interventions to the axillary region. The major nerve trunks of the thoracic limb were the suprascapular, subscapular, axillary, radial, musculocutaneous, median and ulnar nerves. In Van cats, the brachial plexus was formed by the ventral branches of the spinal nerves, C6-C7-C8 and T1. The 7th cervical nerve was quite thick compared to the others. The subscapular nerve was the thinnest (on the right side, the average length was 6.55 ± 0.60 mm and on the left side was 6.50 ± 0.60 mm), and the radial nerve was the thickest (the average length on the right side was 28.48 ± 0.44 mm and on the left side was 29.11 ± 0.55 mm). The suprascapular nerve was formed by the ventral branch of the 6th cervical nerve. The subscapular nerves were formed by a branch originating from the 6th cervical nerve and the two medial and caudal branches originating from the 7th cervical nerve. No communicating branch between the ulnar nerve and the median nerve was observed in the palmar region. The axillary nerve was formed by the ventral branches of the 7th nerve, the musculocutaneous nerve was formed by ventral branches of the 6th and 7th cervical nerves, and the ulnar nerve was formed by ventral branches of the 8th cervical and the 1st thoracic nerves. The radial nerve was the thickest branch in the brachial plexus. In Van cats, the origin and distribution of nerves were similar to those reported in the literature for other species of cats, with the exception of the suprascapular, subscapular and axillary nerves.  相似文献   
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Terrestrial laser scanning technology is an advanced active remote sensing ranging method that is well suited for yielding high-resolution scans of the morphology of a tree, which is an indicator of the health of the plant. The Ganoderma boninense fungus causes basal stem rot (BSR), which threatens the oil palm industry in Malaysia. To date, the current practice of inspection in a plantation is conducted every 6 months. Monitoring the progress with a closer gap is required to comprehend if any changes can be seen earlier than 6 months. Therefore, the objectives of this study were to identify the most suitable parameters of the oil palm trees to detect the BSR disease based on temporal laser scanning data and to identify suitable time frames for monitoring the progress of the symptoms of the disease. Terrestrial laser scanning data was used to analyse changes in the crown and frond metrics of oil palm trees with two different scan durations i.e., 2- and 4-months after the first scan. This spatio-temporal data is important in the precision agriculture field for better oil palm management, to understand the disease development for long-term solutions and also to provide a fast response so that appropriate treatment can be given to the palm as early as possible. Statistical analyses, i.e., the Kruskal–Wallis test with α?=?0.05 and the Wilcoxon post-hoc test, were conducted to determine significant differences in the parameters at different points in time. The results show that crown strata number 17 (850 cm from the top) and the crown area were the most suitable parameters to be used. Furthermore, the oil palm trees with BSR can be detected by comparing the 4-month scan or the second 2-month scan. The results have shown that the effect of Ganoderma boninense infection can be differentiated at the later stage. In conclusion, the changes can be measured at 4-months after the first inspection, thus helping to preventing crop losses.

  相似文献   
55.
Homestead forests contribute substantially to the rural economy of Bangladesh. Rural people depend on trees and plants for their energy usage, housing, food and other forms of subsistence livelihood. In order to identify the potential role of forests on homestead dwellers, an empirical field investigation was conducted in the four Upazilas of Mymensingh district of Bangladesh. It was found that land holdings of the respondents within the four sites are the highest in Mymensingh. The study made an important observation that among all homestead vegetation between 5–6 years old, tree species are generally preferred over plants. This is perhaps due to the efforts of the social forestry extension service to demonstrate that planting trees is an important long-term investment. In all four Upazilas, there was a significant correlation between household annual income and homestead forestry, agriculture and fisheries practice, suggesting that higher income families tend to have larger holdings of homesteads, farms and pond areas. Three Upazilas displayed a strong positive relationship (nearly 45%) between homestead forest areas and annual family income; however, the Fulbaria Upazila showed a very poor relationship (0.2%) in this regard. The results of this study suggest that homestead forests play a positive role in the rural economy, in addition to helping mitigate the increasing problem of deforestation in Bangladesh.  相似文献   
56.
The epidemic of bud rot disease affecting oil palm in Colombia is primarily caused by Phytophthora palmivora. The pathogen has a cosmopolitan presence that includes Southeast Asia, but to date, bud rot has not been reported in this region. This study provides an overview of the potential risk of Malaysian P. palmivora isolates cross‐infecting other host species, including cocoa, durian, rubber and Malaysian oil palm planting materials (Dura × Pisifera, D × P). On cocoa pods, the durian isolate PP7 caused dark brown necrotic lesions. Detached leaf bioassays showed that P. palmivora isolates PP3 and PP7 infected different hosts, except rubber foliage without wounding. Inoculation tests on cocoa, durian and rubber seedlings caused brown necrotic lesions when stems were wounded, with 10% mortality in cocoa and durian at 17 days post‐inoculation (dpi). However, no further infection was observed, and lesions closed within 14–28 dpi on the non‐wounded seedlings. Pathogenicity tests of oil palm seedlings inoculated with isolates PP3 and PP7 indicated that Malaysian P. palmivora isolates were not pathogenic to oil palms based on localized infection observed only through wounding. Overall, the work demonstrated that Malaysian P. palmivora isolates were able to cross‐infect multiple hosts but did not show severe infections on oil palms.  相似文献   
57.
Fucoxanthin is a major carotenoid in brown macroalgae and diatoms that possesses a broad spectrum of health benefits. This review evaluated the research trends of the fucoxanthin field from 1928 to June 2021 using the bibliometric method. The present findings unraveled that the fucoxanthin field has grown quickly in recent years with a total of 2080 publications. Japan was the most active country in producing fucoxanthin publications. Three Japan institutes were listed in the top ten productive institutions, with Hokkaido University being the most prominent institutional contributor in publishing fucoxanthin articles. The most relevant subject area on fucoxanthin was the agricultural and biological sciences category, while most fucoxanthin articles were published in Marine Drugs. A total of four research concepts emerged based on the bibliometric keywords analysis: “bioactivities”, “photosynthesis”, “optimization of process’’, and “environment”. The “bioactivities” of fucoxanthin was identified as the priority in future research. The current analysis highlighted the importance of collaboration and suggested that global collaboration could be the key to valorizing and efficiently boosting the consumer acceptability of fucoxanthin. The present bibliometric analysis offers valuable insights into the research trends of fucoxanthin to construct a better future development of this treasurable carotenoid.  相似文献   
58.
Background:Levan or fructan, a polysaccharide of fructose, is widely used in various commercial industries. Levan could be produced by many organisms, including plants and bacteria. The cloning of the gene from Bacillus licheniformis, which expressed levansucrase in Escherichia coli host, was carried out successfully. In the present study, we performed the in vitro production of levan and analyzed its potential application as antibacterial and antioxidant agents. Methods: In vitro levan production catalyzed by heterologous-expressed levansucrase Lsbl-bk1 and Lsbl-bk2 was optimized with BW design. The antibacterial activity of the produced levan was carried out using agar well diffusion method, while its antioxidant activity was tested by free radical scavenging assays. Results:The optimum conditions for levan production were observed at 36 °C and pH 7 in 12% (w/v) sucrose for levansucrase Lsbl-bk1, while the optimum catalysis of levansucrase Lsbl-bk2 was obtained at 32 oC and pH 8 in the same sucrose concentration. The in vitro synthesized levan showed an antibacterial activity within a concentration range of 10-20% (w/v) against Staphylococcus aureus, E. coli, and Pseudomonas aeruginosa. The same levan was also able to inhibit the DPPH radical scavenging activity with the antioxidant strength of 75% compared to ascorbic acid inhibition. Conclusion:Our study, therefore, shows that the optimized heterologous expression of levansucrases encoded by Lsbl-bk1 and Lsbl-bk2 could open the way for industrial levan production as an antibacterial and antioxidant agent. Key Words: Antioxidants, Fructans, In vitro technique, Levan  相似文献   
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ABSTRACT:   Expressed sequence tag (EST) analysis is an efficient tool for gene discovery and for profiling gene expression. A cDNA library developed from messenger RNA of the Japanese flounder, Paralichthys olivaceus spleen was constructed by directional cloning, in order to isolate functional genes involved in immunity in fish. A total of 1010 ESTs from the library were sequenced and compared with sequences in the GenBank database. Of the 1010 ESTs, 618 ESTs (61%) were identified as being homologous with known genes from many organisms by BLAST searches, whereas 392 (39%) appeared to be unknown and are likely to represent newly described genes. Of the identified genes, 105 (17%) encoded proteins associated with cell/organism defence and homeostasis. Of these 105 genes, 21 were identified for the first time in Japanese flounder. These included macrophage inflammatory protein (MIP)-3 α, granulin-A, novel immune-type receptor (NITR), interferon regulatory factor (IRF)-10, presenilin-like protein-2, and antizyme inhibitor. A comparison of ESTs derived from spleen, kidney, liver and leukocytes suggested that expression of immune-related genes in different tissues, organs, or cells are different.  相似文献   
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