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871.
Neurotensin, at less than or equal to 10(-9) M, in the presence of an optimal concentration of macrophage CSF (CSF-1), stimulated a dose-dependent enhancement of colony formation by murine marrow-derived mononuclear phagocyte progenitor cells. The additional colonies arose from the cell cycle and Ia Ag-positive subpopulation previously identified as two-signal-dependent progenitors. Two-signal colony formation diminished when the peptide was added at concentrations greater than 10(-9) M. Neurotensin binds specifically to two distinct receptors, a high affinity receptor (KD approximately 10(-9) M) and a lower affinity (KD approximately 10(-7) M) receptor identified as the tuftsin receptor. Rat liver ferritin and an inhibitory tuftsin analog. (ALA1)-tuftsin, which inhibit two-signal colony formation stimulated by tuftsin and tuftsin-like peptides in combination with CSF-1, did not inhibit colony formation stimulated by CSF-1 and 10(-9) M neurotensin. Both inhibitors, however, reversed the loss of two-signal colony growth in the presence of higher neurotensin concentrations. Neurotensin fragment 1-6, unlike ferritin and (ALA1)-tuftsin, inhibited two-signal colony formation stimulated by 10(-9) M neurotensin. However, like ferritin and (ALA1)-tuftsin, fragment 1-6 permitted full expression of two-signal colony formation in the presence of CSF-1 and 10(-7) M neurotensin. The data indicated that occupancy of both receptors at neurotensin concentrations greater than 10(-9) M might be responsible for the diminished progenitor response. The data further support a potential role for neurotensin as an inflammatory mediator. In addition to direct effects on mature phagocytic leukocytes, neurotensin, at least in vitro can influence the production of new mononuclear phagocytes.  相似文献   
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The use of different seaweeds such as Sargassum sp., Turbinaria conoides, and Ulva sp. in removing mercury(II) from aqueous solutions were investigated. The initial experimental runs, conducted at different equilibrium pH conditions, demonstrated that brown seaweeds outperformed green seaweed in Hg(II) biosorption at all pH conditions. In particular, at pH 5, maximum biosorption capacities of 170.3 and 145.8 mg/g were recorded for the brown seaweeds T. conoides and Sargassum sp., respectively, compared with 138.4 mg/g for the green seaweed Ulva sp. Isotherm data were modeled and interpreted using the Langmuir, Freundlich, Redlich-Peterson, and Toth models, with the latter described the Hg(II) isotherms with high correlation coefficients and low % error values. The kinetic data indicate the rapidity of the biosorption process, with the equilibrium achieved within 90 min. Several models, including the Elovich, pseudo-first-order, and pseudo-second-order models, were examined for their suitability with the present data; the correlation coefficient and % error values, along with better prediction of equilibrium uptake values, favored the pseudo-first-order model. The desorption experiments were highly successful for T. conoides biomass with 0.05 M HCl, whereas for the other two seaweeds, 0.05 M HCl resulted in high biomass weight loss. Reusing T. conoides biomass in three successive sorption-desorption cycles resulted in only 8.8% reduction in Hg(II) biosorption capacity compared with its original uptake.  相似文献   
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Molecular and Cellular Biochemistry - Antibiotics are the front-line treatment against many bacterial infectious diseases in human. The excessive and long-term use of antibiotics in human cause...  相似文献   
874.
Oral infections have a strong ethnic predilection; suggesting that ethnicity is a critical determinant of oral microbial colonization. Dental plaque and saliva samples from 192 subjects belonging to four major ethnicities in the United States were analyzed using terminal restriction fragment length polymorphism (t-RFLP) and 16S pyrosequencing. Ethnicity-specific clustering of microbial communities was apparent in saliva and subgingival biofilms, and a machine-learning classifier was capable of identifying an individual’s ethnicity from subgingival microbial signatures. The classifier identified African Americans with a 100% sensitivity and 74% specificity and Caucasians with a 50% sensitivity and 91% specificity. The data demonstrates a significant association between ethnic affiliation and the composition of the oral microbiome; to the extent that these microbial signatures appear to be capable of discriminating between ethnicities.  相似文献   
875.
In the present study, we report the distribution of true to type and atypical Nili-Ravi buffalo, a vulnerable dairy type riverine breed of North India and its underlying genetic structure. Out of total investigated buffaloes 73.5% had bilateral wall eyes while 5.4% had unilateral wall eyes and 21.1% had no wall eyes. 41.15% of Nili-Ravi buffaloes maintained in the breeding farm were having typical true to the type characteristics (both eyes walled, white markings in forehead, muzzle/chin, all the four legs and tail) while only 28.5% of Nili-Ravi buffaloes were true to the type under field conditions. Genotypic data were generated in four groups of Nili-Ravi buffalo (FMTNR—Typical Nili-Ravi from farm; FMANR—Atypical Nili-Ravi from farm; FDTNR—Typical Nili-Ravi from field; FDANR—Atypical Nili-Ravi from field) at 16 microsatellite loci. Comparative genetic analysis of various groups of Nili-Ravi buffaloes with Murrah revealed significant between group differences with an estimated global F ST of 0.063. Pair-wise F ST values ranged from 0.003 (between FDTNR and FDANR) to 0.112 (between FMTNR and FDTNR). Phylogenetic analysis and multi-dimensional scaling revealed clustering of FDTNR and FDANR together while FMTNR and FMANR clustered separately with Murrah in between farm and field Nili-Ravi buffaloes. Based on the results, the paper also proposes three pronged strategy for conservation and sustainable genetic improvement of Nili-Ravi buffalo in India.  相似文献   
876.
Experiments were conducted to investigate the relationship between ultraviolet (UV) C-induced oxidative damage and the activity of ascorbate peroxidase (APX), using transgenic tobacco (Nicotiana tabacum L. cv. Petit Havana) plants overexpressing cytosolic APX gene (apx1). Transgenic plants having 2.3 fold higher total APX activity, as compared to the wild type plants, showed normal morphological characters. Exposure of 70-day-old plants to fixed intensity UV-C radiation caused an increase in the malondialdehyde (MDA) content in wild type as well as transgenic plants. However, the wild type plants showed significantly higher (p < 0.05) lipid peroxidation as compared to the transgenic plants. Higher proline accumulation was recorded in transgenic plants as compared to the wild type plants, after 24 hours of UV-C exposure. Although the ascorbate content decreased continuously with increasing exposure to UV-C radiation, yet the wild type plants exhibited higher ascorbate levels than the transgenic plants. A marked difference in H2O2 content, between the wild type and transgenic plants, was consistently observed up to 20 hours of UV-C exposure. A direct correlation of ascorbate, MDA and H2O2 levels was recorded with the extent of oxidative stress, signifying that these could be used as potential bio-marker molecules for oxidative stress. The results clearly demonstrate that overexpression of cytosolic APX can protect tobacco plants from UV-C-induced oxidative damage.  相似文献   
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Russian Journal of Bioorganic Chemistry - An efficient, simple, and greener method has been described for the synthesis of 3-(2-chlorobenzyl)-6-(substituted...  相似文献   
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