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531.
Bacillus firmus strongly stimulates Ig synthesis in the cultures of human peripheral blood mononuclear leukocytes. As apparent from the character
of Ig formation and blastic transformation, the stimulation has features of a polyclonal activation of B lymphocytes without
substantial participation of T lymphocytes.B. firmus is a strong B cell polyclonal activator even for human cord blood lymphocytes. The most striking feature is the strong stimulation
of IgA synthesis in both adult and cord blod lymphocytes. Several crude fractions were isolated fromB. firmus. None of them exhibited any remarkable enhancement of activity but the cytoplasmic fraction P-40 was clearly more potent
than the intact bacilli. On the other hand, cell wall peptidoglycan, a well known polyclonal activator of B cells, had a much
lower activity than whole bacteria. The effect ofB. firmus on the stimulation of Ig formation is thus relatively complex; it is not caused mainly by peptidoglycan but rather by some
cytoplasmic constituents of the bacterium.
Dedicated to Professor C. John on the occasion of his 75th birthday 相似文献
532.
The oxidation of gallic acid by an enzyme preparation isolated from the culture medium ofNicotiana tabacum cell suspension could be followed by means of fast scan differential pulse polarography (DPP). A product was formed which could be reduced by means of DPP at- 0.47 V (MSE). The nature of the oxidation products is discussed. 相似文献
533.
Pi uptake in cells or spheroplasts ofParacoccus denitrificans is biphasic; only the first rapid phase represents net Pi transport. The second phase is limited by the rate of Pi utilization inside the cell, i.e., mainly by its esterification, and as such it was inhibited by DCCD. The Pi/dicarboxylate antiporter does not seem to be operative, and its inhibitorn-butylmalonate did not exert specific inhibition. Pi transport is inhibited by SH reagents; the most potent inhibitor is PCMB, and mersalyl is much less effective. However, neither inhibitor affects efflux of accumulated Pi. The gradient of potassium ions may be involved in the Pi uptake, which is lowered in the presence of valinomycin. FCCP alone does not release accumulated Pi from spheroplasts unless they are preincubated with SCN?. The results indicate that Pi enters the cell by symport with protons. 相似文献
534.
Thirty-eight pigs were immunized with normal human γG-, γA- and γM-immunoglobulins, fragments of γG-immunoglobulin (Fab, Fc+F'c),
type K and L Bence-Jones proteins and other antigens containing immunoglobulins or their fragments. The pigs formed antibodies
readily against the heavy γ, α, μ and δ chains and also against η chains. No antibodies whatsoever were formed against the
surface determinants of λ chains; the antibodies present reacted only with hidden determinants of these chains. In isolated
cases, antibodies against the Fd fragments of γG-immunoglobulin were also identified. A quantitative precipitation test showed
that porcine antibodies are of the “R”, precipitin, type. 相似文献
535.
Breast cancer is known as the most common type of invasive cancer in women. It is well-known that phenolic compounds play an important role in the treatment of this disease. This study hypothesized that isoeugenol based two polyphenolic compounds 1 and 2 exerts its anti-proliferative effects through the induction of apoptosis and cell migration arrest on human breast cancer cell. Based on this hypothesis, the study aimed to investigate the anti-proliferative, anti-migrative effects of these compounds and their possible basic molecular mechanisms of action in MCF-7 cell lines. As a result, isoeugenol-based compounds 1 and 2 showed anti-proliferative, anti-apoptotic and anti-migrative effects in MCF-7 breast cancer cells. This result was supported by molecular analyzes and it was determined that there were changes in the expression of some gene regions involved in apoptosis and migration. Additionally, it was a remarkable result that cell viability inhibition did not occur in healthy breast tissue cells and no cytotoxic effect was observed. The existence of such a differentiation between cancer cells and healthy cells significantly increases the potential of these compounds to be used as chemotherapeutic drug active ingredients without side effects. 相似文献
536.
The PsbS protein is a critical component in the regulation of non-photochemical quenching (NPQ) in higher plant photosynthesis. Electron microscopy and image analysis of grana membrane fragments from wild type and mutant Arabidopsis plants showed that the semi-crystalline domains of photosystem II supercomplexes were identical in the presence and absence of PsbS. However, the frequency of the domains containing crystalline arrays was increased in the absence of PsbS. Conversely, there was a complete absence of such arrays in the membranes of plants containing elevated amounts of this protein. It is proposed that PsbS controls the macro-organisation of the grana membrane, providing an explanation of its role in NPQ. 相似文献
537.
Streptomyces cinnamonensis produces a new substance named AIB (for anti-isobutyrate) factor which, on a solid medium, efficiently counteracts toxic
concentrations not only of isobutyrate but also of other salts of short-chain monocarboxylic acids. In the present study we
demonstrate that the AIB factor activity is widely spread because this effect was positively detected in 25 of 31 randomly
chosen microorganisms (streptomycetes, ascomycetes, zygomycetes and basidiomycetes). The AIB factor produced by the tested
microorganisms on an agar media allows for germination, growth, and sporulation of the testingStreptomyces coelicolor on an agar medium containing 20 mmol/L acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and 2-methylbutyrate.
The activity of the AIB factor from different sources towards these substances differs. 相似文献
538.
539.
540.
F. Škvařil 《Folia microbiologica》1960,5(4):264-271
Во время хранения, человека γ-глобулин препараты протеолиза проходить медленно, в результате в составе двух фракций сплит. Один из них (γx) медленнее, чем обычно γ-глобулин, в то время как другие (γи) больше быстрыми темпами. Темпы разрушения в плазме подготовка охватывает несколько лет, тогда как в препаратов, полученных в результате haemolysed и плацентарной материала это несколько месяцев. Аналогичная разбивка была искусственно вызванной в плазмин, trypsin и papain. Определенный артикль изменения могут быть обнаружены путем immunoelectrophoresis, но электрофореза в Агар и высокоскоростного центрифугирования также дают приблизительную картину состояния подготовки. Определенный артикль γx дроби могут быть восстановлены в immunoelectrophoretically чистом состоянии путем осадков с сульфата аммония (более 50% насыщения), или с Zn2+ солей (в supernatant жидкости составляет более 50 мм концентрация). Определенный артикль γи фракция crystallizes из решений с низкой ионной силы в виде минуту, игла-как, оптически неактивных кристаллов. Причины изменений в соответствующую препаратов и биохимических и Иммунохимические аспекты с учетом явления рассматриваются. 相似文献