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951.
Light inhibited the growth and glucose consumption of colorlessmutant cells of Chlorella vulgaris (# 125). Sugar consumptionwas also inhibited in a medium containing a hexose such as D-fructose,D-galactose and D-mannose. Blue light strongly inhibited growth and glucose consumptionbut red light only slightly affected them. Respiration was notinhibited by blue light. The inhibitions of growth and glucoseconsumption were saturated at light intensities as low as 800mW.m2 and continued in the dark for at least one dayafter brief illumination with white light. The half-maximumeffect was observed with 15 min of illumination in both casesand the action spectra for light-induced inhibitions of growthand glucose consumption were similar, both showing peaks at370, 457 and 640 nm. The role of light in the inhibitions of growth and glucose consumptionis discussed. (Received June 18, 1984; Accepted October 29, 1984) 相似文献
952.
A platelet factor stimulating the proliferation of vascular endothelial cells: Partial purification and characterization 总被引:2,自引:0,他引:2
Kohei Miyazono Tetsuro Okabe Shun Ishibashi Akio Urabe Fumimaro Takaku 《Experimental cell research》1985,159(2):487-494
Platelets have been shown to contain a novel growth factor that stimulates the proliferation of vascular endothelial cells in vitro. The factor potently stimulated both DNA synthesis and proliferation rate in serum-deprived endothelial cells. Gel exclusion chromatography showed at least two peaks of activity on endothelial cells, the major peak being at an apparent molecular weight of 20 000. Isoelectric focusing revealed that the pI of the factor was 4.0-4.8. It was adsorbed to a column of DEAE ion exchange chromatography and eluted with a salt gradient. The factor was heat-labile and trypsin-sensitive. The activity was not destroyed by a reducing agent including dithiothreitol. This factor stimulated the proliferation of vascular endothelial cells but was found to be inactive against normal rat kidney fibroblasts. 相似文献
953.
The white rot fungus Phanerochaete chrysosporium metabolized the lignin model compounds veratylglycerol--guaiacyl ether I and 4-ethoxy-3-methoxy-phenylglycerol--guaiacyl ether V in stationary culture under an atmosphere of 100% oxygen and under nitrogen limiting conditions. 2-(o-methoxyphenoxy)-ethanol VII was identified as a product of the metabolism of both substrates. Veratryl alcohol and 4-ethoxy-3-methoxybenzyl alcohol IV were identified as metabolites of I and V respectively. Metabolites were identified after comparison with chemically synthesized standards by mass spectrometry. These results indicate the existence of an enzyme system capable of directly cleaving the etherated dimers I and V at the , bond. The additional identification of 2-(o-methoxyphenoxy)-1,3 propanediol IX as a metabolic product indicates that cleavage of the alkyl-phenyl bond of these dimers or their metabolites also occurs.Abbreviations GLC
Gas liquid chromatography
- TMSi
trimethylsilyl
- TLC
Thin layer chromatography 相似文献
954.
955.
Limnology - Appropriate management of macrophyte biomass via harvesting is crucial for maintaining eutrophic inland waters. However, information on the effects of macrophyte harvesting on the... 相似文献
956.
957.
Dendritic cell-based vaccines suppress metastatic liver tumor via activation of local innate and acquired immunity 总被引:2,自引:0,他引:2
Yamaguchi S Tatsumi T Takehara T Sasakawa A Hikita H Kohga K Uemura A Sakamori R Ohkawa K Hayashi N 《Cancer immunology, immunotherapy : CII》2008,57(12):1861-1869
Background Dendritic cell (DC)-based vaccines have been applied clinically in the setting of cancer, but tumor-associated antigens (TAAs)
have not yet been enough identified in various cancers. In this study, we investigated whether preventive vaccination with
unpulsed DCs or peptide-pulsed DCs could offer anti-tumor effects against MC38 or BL6 liver tumors.
Methods Mice were subcutaneously (s.c.) immunized with unpulsed DCs or the recently defined TAA EphA2 derived peptide-pulsed dendritic
cells (Eph-DCs) to treat EphA2-positive MC38 and EphA2-negative BL6 liver tumors. Liver mononuclear cells (LMNCs) from treated
mice were subjected to 51Cr release assays against YAC-1 target cells. In some experiments, mice were injected with anti-CD8, anti-CD4 or anti-asialo
GM1 antibody to deplete each lymphocyte subsets.
Results Immunization with unpulsed DCs displayed comparable efficacy against both MC38 and BL6 liver tumors when compared with Eph-DCs.
Both DC-based vaccines significantly augmented the cytotoxicity of LMNCs against YAC-1 cells. In vivo antibody depletion studies
revealed that NK cells, as well as, CD4+ and CD8+ T cells play critical roles in the anti-tumor efficacy associated with either
DC-based modality.
Tumor-specific cytotoxic T lymphocyte (CTL) activity was generally higher if mice had received Eph-DCs versus unpulsed DCs.
Importantly, the mice that had been protected from MC38 liver tumor by either unpulsed DCs or Eph-DCs became resistant to
s.c. MC38 rechallenge, but not to BL6 rechallenge.
Conclusions These results demonstrate that unpulsed DC vaccines might serve as an effective therapy for treating metastatic liver tumor, for which TAA has not yet been identified.
Shinjiro Yamaguchi and Tomohide Tatsumi contributed equally to this work. 相似文献
958.
Deguchi Y Toyoizumi T Masuda S Yasuhara A Mohri S Yamada M Inoue Y Kinae N 《Mutation research》2007,627(2):178-185
To develop a simple system for monitoring the presence of mutagens/carcinogens in the leachates from landfill sites, we used a micronucleus test and a single cell gel electrophoresis (comet) assay originally developed for mice and rats on goldfish (Carassius auratus). The goldfish were exposed for 9 days to the leachate with chemical and biological treatment (treated leachate) or without treatment (raw leachate). The goldfish exposed to several samples died because of the high concentrations of NaCl or ammonium ion (NH4+). In the comet assay using peripheral erythrocytes, the raw leachates showed higher mutagenic activity than the treated leachates. In the micronucleus test, it was difficult to detect the micronuclei in peripheral erythrocytes. On the other hand, the frequency of micronuclei was high in gill cells of goldfish exposed to the raw leachates compared to the treated leachates. A combination of the two bioassays was shown to be useful to evaluate the mutagenic activity of the leachates. We also propose a new scoring method for determination of water quality by using acute toxicity and mutagenic activity. 相似文献
959.
960.
Husain K Vazquez M Ansari RA Malafa MP Lalla J 《Molecular and cellular biochemistry》2008,307(1-2):51-58
The link between chronic alcohol consumption and cardiovascular injury including hypertension is well known. However, molecular
mediators implicated with alcohol-induced elevation in blood pressure (BP) remain elusive. The aim of this study was to investigate
the relationship of chronic ethanol-induced endothelial injury and elevation in BP with angiotensin II levels in rats. Male
Fisher rats were divided into two groups of seven animals each and treated as follows: (1) Control (5% sucrose, orally) daily
for 12 weeks and (2) ethanol (4 g kg−1, orally) daily for 12 weeks. The BP (systolic, diastolic, and mean) was recorded every week. The animals were anesthetized
with pentobarbital after 12 weeks; blood and thoracic aorta were isolated and analyzed for aortic reactivity response, angiotensin
II levels, and oxidative endothelial injury. The results show that the systolic, diastolic, and mean BP were significantly
elevated 12 weeks after ethanol ingestion. The increased BP was related to elevated angiotensin II levels in the plasma and
aorta of alcohol treated group compared to control. The aortic NADPH oxidase activity, ratio of oxidized to reduced glutathione
(GSSG/GSH) and lipid peroxidation significantly increased, whereas nitric oxide (NO), endothelial NO synthase (eNOS), and
vascular endothelial growth factor (VEGF) protein expressions were depressed in alcohol group compared to control. The phenylephrine-mediated
vasoconstriction response was not altered, while acetylcholine-mediated vasorelaxation response was depressed in the aorta
of ethanol treated rats compared to control. It is concluded that chronic ethanol ingestion induces hypertension which is
correlated with elevated tissue angiotensin II levels, activation of NADPH oxidase activity causing endothelial injury, depletion
of endothelial NO generating system, and impaired vascular relaxation in rats. 相似文献