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101.
Pressure-volume technique was utilized to evaluate salinity response among three populations ofSpartina patens (Ait.) Muhl. from Louisiana Gulf coast marshes. Plants were subjected to salinities of 85 and 425 mol m?3 for 77 d in a greenhouse. Ψw and Ψπ decreased in all populations in response to increases in salinity. There were 32% decrease in Ψsat, 42% decrease in Ψtlp in response to salinity changes from 85 to 425 mol m?3 in the Ferblanc population. Similarly, there were 35% and 41% decrease in Ψsat in the Clovelly and Lake Tambour populations, respectively. All populations showed the ability to adapt to the increased salinity as was evidenced by osmotic adjustment. However, the Lake Tambour population appeared to have superior ability to adapt to high salinity through having a significantly lower osmotic potential at saturation (Ψsat), osmotic potential at turgor loss point (Ψtlp), and maximum turgor potential (ΨP(max)) compared to other populations. Ferblanc and Clovelly populations revealed the ability to adapt to saline environments to a lesser extent as compared to the Lake Tambour population. Results indicate that there is a potential for selection of superior strains ofSpartina patens for use in marsh restoration projects aiming at prevention of wetland loss in certain coastal areas. 相似文献
102.
Takenobu Ishii Montserrat Ruiz-Torruella Jae Young Kim Hiroyuki Kanzaki Abdullah Albassam Wichaya Wisitrasameewong Satoru Shindo Roodelyne Pierrelus Alireza Heidari Umadevi Kandalam Shin Nakamura Alexandru Movila Dmitriy Minond Toshihisa Kawai 《Journal of cellular and molecular medicine》2023,27(12):1750-1756
Bone remodelling is mediated by orchestrated communication between osteoclasts and osteoblasts which, in part, is regulated by coupling and anti-coupling factors. Amongst formally known anti-coupling factors, Semaphorin 4D (Sema4D), produced by osteoclasts, plays a key role in downmodulating osteoblastogenesis. Sema4D is produced in both membrane-bound and soluble forms; however, the mechanism responsible for producing sSema4D from osteoclasts is unknown. Sema4D, TACE and MT1-MMP are all expressed on the surface of RANKL-primed osteoclast precursors. However, only Sema4D and TACE were colocalized, not Sema4D and MT1-MMP. When TACE and MT1-MMP were either chemically inhibited or suppressed by siRNA, TACE was found to be more engaged in shedding Sema4D. Anti-TACE-mAb inhibited sSema4D release from osteoclast precursors by ~90%. Supernatant collected from osteoclast precursors (OC-sup) suppressed osteoblastogenesis from MC3T3-E1 cells, as measured by alkaline phosphatase activity, but OC-sup harvested from the osteoclast precursors treated with anti-TACE-mAb restored osteoblastogenesis activity in a manner that compensates for diminished sSema4D. Finally, systemic administration of anti-TACE-mAb downregulated the generation of sSema4D in the mouse model of critical-sized bone defect, whereas local injection of recombinant sSema4D to anti-TACE-mAb-treated defect upregulated local osteoblastogenesis. Therefore, a novel pathway is proposed whereby TACE-mediated shedding of Sema4D expressed on the osteoclast precursors generates functionally active sSema4D to suppress osteoblastogenesis. 相似文献
103.
Oral liposarcomas are uncommon diseases, the most predominant histopathological subtype being atypical lipomatous tumour/well-differentiated liposarcoma. In regard to its clinical aspects in the oral cavity, it is challenging to confirm a diagnosis and develop a treatment plan. In this case report, we present a rare case of atypical lipomatous tumour/well-differentiated liposarcoma in the right cheek of a 77-year-old male patient. Conservative surgery was performed considering the histopathological subtype of the neoplasm. Knowledge of the clinical and histopathological characteristics of this rare disease is essential to maintaining function and aesthetics through conservative treatment in older patients. 相似文献
104.
Jong An Lee Jung Ho Ahn Gi Bae Kim Sol Choi Ji Yeon Kim Sang Yup Lee 《Biotechnology and bioengineering》2023,120(1):203-215
Microbial production of various TCA intermediates and related chemicals through the reductive TCA cycle has been of great interest. However, rumen bacteria that naturally possess strong reductive TCA cycle have been rarely studied to produce these chemicals, except for succinic acid, due to their dependence on fumarate reduction to transport electrons for ATP synthesis. In this study, malic acid (MA), a dicarboxylic acid of industrial importance, was selected as a target chemical for mass production using Mannheimia succiniciproducens, a rumen bacterium possessing a strong reductive branch of the TCA cycle. The metabolic pathway was reconstructed by eliminating fumarase to prevent MA conversion to fumarate. The respiration system of M. succiniciproducens was reconstructed by introducing the Actinobacillus succinogenes dimethylsulfoxide (DMSO) reductase to improve cell growth using DMSO as an electron acceptor. Also, the cell membrane was engineered by employing Pseudomonas aeruginosa cis-trans isomerase to enhance MA tolerance. High inoculum fed-batch fermentation of the final engineered strain produced 61 g/L of MA with an overall productivity of 2.27 g/L/h, which is the highest MA productivity reported to date. The systems metabolic engineering strategies reported in this study will be useful for developing anaerobic bioprocesses for the production of various industrially important chemicals. 相似文献
105.
I. Molnár N. Hayashi K.-P. Choi H. Yamamoto M. Yamashita Y. Murooka 《Molecular microbiology》1993,7(3):419-428
A new metabolite of cholesterol was found in reaction mixtures containing cholesterol or 4-cholesten-3-one as a substrate and extra- or intracellular protein extracts from recombinant Streptomyces lividans and Escherichia coli strains carrying cloned DNA fragments of Streptomyces sp. SA-COO, the producer of Streptomyces cholesterol oxidase. The new metabolite was identified as 4-cholesten-6-ol-3-one based on comparisons of its high-performance liquid chromatography, gas chromatography/mass spectrometry, infrared and proton-nuclear magnetic resonance spectra with those of an authentic standard. Genetic analyses showed that the enzyme responsible for the production of 4-cholesten-6-ol-3-one is cholesterol oxidase encoded by the choA gene. Commercially purified cholesterol oxidase (EC 1.1.3.6.) of a Streptomyces sp., as well as of Brevibacterium sterolicum and a Pseudomonas sp., and a highly purified recombinant Streptomyces cholesterol oxidase were also able to catalyse the 6-hydroxylation reaction. Hydrogen peroxide accumulating in the reaction mixtures as a consequence of the 3β-hydroxysteroid oxidase activity of the enzyme was shown to have no role in the formation of the 6-hydroxylated derivative. We propose a possible scheme of a branched reaction pathway for the concurrent formation of 4-cholesten-3-one and 4-chotesten-6-ol-3-one by cholesterol oxidase, and the observed differences in the rate of formation of the 6-hydroxy-ketosteroid by the enzymes of different bacterial sources are also discussed. 相似文献
106.
107.
Total 2,829 persons consisted of 1,019 general patients and 1,030 asthma-suspected patients who visited Kangnam St. Mary's Hospital and 780 general patients who visited Cheju Medical Center were examined for the antibody titers of Toxoplasma by indirect latex agglutination (ILA) test. Nineteen out of 1,019(1.86%) cases in general patients group, 11 out of 1,030(1.07%) cases in asthma patients group, and 45 out of 780(5.77%) cases in Cheju patients group showed positive ILA titers. Concerned with the age and ILA positive cases, general and asthma patients expressed more cases at thirties to sixties while Cheju patients showed high incidence at children and adolescents in addition to the above mentioned ages. Frequencies of ILA positive titers were highest in 1:32 and 1:64, and some cases showed 1:2,048 or higher titers. 相似文献
108.
Complete mRNA sequence of transferrin from Galleria mellonella was obtained, and compared with those of other species. Until now, two types of insect transferrin were reported. Transferrins in cockroach and termite have two iron binding sites while those in most other insect groups, studied for the protein, have only one. It was suggested that the presence of two types of transferrin was related with transferrin evolution, because vertebrate transferrins have two iron binding sites, called N and C terminal lobe. It was shown that G. mellonella transferrin also has only one iron binding site (N terminal lobe), and the deduced amino acid sequence was most similar to those of Manduca sexta and Bombyx mori. 相似文献
109.
Complete larval development of Crangon hakodatei Rathbun isdescribed, based on material hatched in the laboratory fromovigerous females. The species has six zoeal stages and onepostlarval stage. The morphological characters of the larvaland postlarval stages are described with illustrative figuresand compared with those of two congeneric species. The zoealstages of C. hakodatei can be distinguished from those of otherCrangon species in the number of segments of the antennule peduncle,the number of setae on the antennal scale and basis of the maxillipeds,and the stages of appearance of pereiopods. The first zoealstage in the seven species of Crangon are compared and an annotatedkey for distinguishing them is also provided. 相似文献
110.
Byoung K. Choi Kwan H. Han Tea Y. Park 《Flexible Services and Manufacturing Journal》1996,8(2):159-182
Presented in the article is a method for constructing a graphical model of an FMS by using a new modeling tool called JR-net (Job Resource relation-net). JR-net is an object-oriented graphical tool for modeling automated manufacturing systems (AMSs), such as FMSs, FASs, and AS/RSs. As with the object-oriented modeling paradigm of Rumbaugh et al. (1991), the JR-net modeling framework supports the three stages of models: static layout model (object model); job flow model (functional model); and supervisory control model (dynamic model). In this article, the existing JR-net structure (Park 1992, Han et al., 1995) is extended further to make it a graphical tool for FMS modeling. Using the extended JR-net, a step-by-step procedure for constructing a graphical model of FMSs is presented. Also addressed are issues of classifying FMSs in terms of their generic functions and of utilizing the JR-net model of FMSs. 相似文献