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21.
Summary The in vitro and in vivo activity has been investigated of antisera prepared against a murine (C-1300) neuroblastoma line (MNB) capable of differentiation. An antibody-dependent cellular cytotoxicity (ADCC) reaction was employed using rat spleen cells (RSC). ADCC activity in vitro (using 51Cr-release) was shown, but a maximum of only 50% of the immunologically releasable 51Cr was achieved. Nevertheless, in vivo (syngeneic mouse-tumor flank assay) significant delays were obtained in tumor onset and lethality. Under ideal circumstances, i.e., coating of tumor cells prior to inoculation and high RSC effector cell ratios, a significant number of animals could be cured of substantial tumor burdens (106 cells). While close proximity of the site of injection of effector cells was required (ectopic injections of RSC were ineffective), the anti-MNB ADCC was shown to be quite active in vivo without external precoating of the cells with antisera. RCS obtained from BCG-treated rats were more numerous and slightly more effective. RSC obtained from -radiated animals retained normal activity. With appropriate antisera this approach could be useful under selected clinical circumstances.  相似文献   
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Desulfovibrio species are Gram-negative anaerobic sulfate-reducing bacteria that colonize the human gut. Recently, Desulfovibrio spp. have been implicated in gastrointestinal diseases and shown to stimulate the epithelial immune response, leading to increased production of inflammatory cytokines by macrophages. Activated macrophages are key cells of the immune system that impose nitrosative stress during phagocytosis. Hence, we have analyzed the in vitro and in vivo responses of Desulfovibrio vulgaris Hildenborough to nitric oxide (NO) and the role of the hybrid cluster proteins (HCP1 and HCP2) and rubredoxin oxygen oxidoreductases (ROO1 and ROO2) in NO protection. Among the four genes, hcp2 was the gene most highly induced by NO, and the hcp2 transposon mutant exhibited the lowest viability under conditions of NO stress. Studies in murine macrophages revealed that D. vulgaris survives incubation with these phagocytes and triggers NO production at levels similar to those stimulated by the cytokine gamma interferon (IFN-γ). Furthermore, D. vulgaris hcp and roo mutants exhibited reduced viability when incubated with macrophages, revealing that these gene products contribute to the survival of D. vulgaris during macrophage infection.  相似文献   
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Purpose  

The purpose of this study is to provide life cycle inventory data and results for components of electrical grids to the larger community of life cycle assessment practitioners. This article is the first in a series of two, each focusing on different components of power grids. In part 1, the objects under scope are power lines and cables. Systems for overhead, underground, and subsea transmission are modeled here, including HVDC systems used in long-distance transmission.  相似文献   
24.
Purinergic Signalling - Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the occurrence of the t(9;22)(q34;q11) translocation. First-line therapy for CML consists...  相似文献   
25.
E-cadherin protein (CDH1 gene) integrity is fundamental to the process of epithelial polarization and differentiation. Deregulation of the E-cadherin function plays a crucial role in breast cancer metastases, with worse prognosis and shorter overall survival. In this narrative review, we describe the inactivating mechanisms underlying CDH1 gene activity and its possible translation to clinical practice as a prognostic biomarker and as a potential targeted therapy.  相似文献   
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Strain MG, isolated from an acidic pond sediment on the island of Milos (Greece), is proposed as a novel species of ferrous iron- and sulfur-oxidizing Acidithiobacillus. Currently, four of the eight validated species of this genus oxidize ferrous iron, and strain MG shares many key characteristics with these four, including the capacities for catalyzing the oxidative dissolution of pyrite and for anaerobic growth via ferric iron respiration. Strain MG also grows aerobically on hydrogen and anaerobically on hydrogen coupled to ferric iron reduction. While the 16S rRNA genes of the iron-oxidizing Acidi-thiobacillus species (and strain MG) are located in a distinct phylogenetic clade and are closely related (98–99% 16S rRNA gene identity), genomic relatedness indexes (ANI/dDDH) revealed strong genomic divergence between strain MG and all sequenced type strains of the taxon, and placed MG as the first cultured representative of an ancestral phylotype of iron oxidizing acidithiobacilli. Strain MG is proposed as a novel species, Acidithiobacillus ferrianus sp. nov. The type strain is MGT (= DSM 107098T = JCM 33084T). Similar strains have been found as isolates or indicated by cloned 16S rRNA genes from several mineral sulfide mine sites.

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Probiotics and Antimicrobial Proteins - The use of natural products together with standard antimicrobial drugs has recently received more attention as a strategy to combat infectious diseases...  相似文献   
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The Mediterranean Basin is a global biodiversity hotspot, hosting a number of native species belonging to families that are found almost exclusively in tropical climates. Yet, whether or not these taxa were able to survive in the Mediterranean region during the Quaternary climatic oscillations remains unknown. Focusing on the European free-tailed bat (Tadarida teniotis), we aimed to (a) identify potential ancient populations and glacial refugia; (b) determine the post-glacial colonization routes across the Mediterranean; and (c) evaluate current population structure and demography. Mitochondrial and nuclear markers were used to understand T. teniotis evolutionary and demographic history. We show that T. teniotis is likely restricted to the Western Palearctic, with mitochondrial phylogeny suggesting a split between an Anatolian/Middle East clade and a European clade. Nuclear data pointed to three genetic populations, one of which is an isolated and highly differentiated group in the Canary Islands, another distributed across Iberia, Morocco, and France, and a third stretching from Italy to the east, with admixture following a pattern of isolation by distance. Evolutionary and demographic reconstruction supports a pre-Last Glacial Maximum (LGM) colonization of Italy and the Anatolian/Middle East, while the remaining populations were colonized from Italy after the Younger Dryas. We also found support for demographic expansion following the Iberian colonization. The results show that during the LGM T. teniotis persisted in Mediterranean refugia and has subsequently expanded to its current circum-Mediterranean range. Our findings raise questions regarding the physiological and ecological traits that enabled species with tropical affinities to survive in colder climates.  相似文献   
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