Antioxidant activity of anti-inflammatory plant extracts

The antioxidant properties of twenty medical herbs used in the traditional Mediterranean and Chinese medicine were studied. Extracts from Forsythia suspensa, Helichrysum italicum, Scrophularia auriculata, Inula viscosa, Coptis chinensis, Poria cocos and Scutellaria baicalensis had previously shown anti-inflammatory activity in different experimental models. Using free radical-generating systems H. italicum. I. viscosa and F. suspensa protected against enzymatic and non-enzymatic lipid peroxidation in model membranes and also showed scavenging property on the superoxide radical. All extracts were assayed at a concentration of 100 microg/ml. Most of the extracts were weak scavengers of the hydroxyl radical and C. chinensis and P. cocos exhibited the highest scavenging activity. Although S. baicalensis inhibited the lipid peroxidation in rat liver microsomes and red blood cells, the extract showed inhibitory actions on aminopyrine N-demethylase and xanthine oxidase activities as well as an pro-oxidant effect observed in the Fe3+-EDTA-H2O2 system. The results of the present work suggest that the anti-inflammatory activities of the same extracts could be explained, at least in part, by their antioxidant properties.     

Atmospheric water vapor as driver of litter decomposition in Mediterranean shrubland and grassland during rainless seasons

Litter production in many drought‐affected ecosystems coincides with the beginning of an extended season of no or limited rainfall. Because of lack of moisture litter decomposition during such periods has been largely ignored so far, despite potential importance for the overall decay process in such ecosystems. To determine drivers and extent of litter decay in rainless periods, a litterbag study was conducted in Mediterranean shrublands, dwarf shrublands and grasslands. Heterogeneous local and common straw litter was left to decompose in open and shaded patches of various field sites in two study regions. Fresh local litter lost 4–18% of its initial mass over about 4 months without rainfall, which amounted to 15–50% of total annual decomposition. Lab incubations and changes in chemical composition suggested that litter was degraded by microbial activity, enabled by absorption of water vapor from the atmosphere. High mean relative humidity of 85% was measured during 8–9 h of most nights, but the possibility of fog deposition or dew formation at the soil surface was excluded. Over 95% of the variation in mass loss and changes in litter nitrogen were explained by characteristics of water‐vapor uptake by litter. Photodegradation induced by the intense solar radiation was an additional mechanism of litter decomposition as indicated by lignin dynamics. Lignin loss from litter increased with exposure to ultraviolet radiation and with initial lignin concentration, together explaining 90%–97% of the variation in lignin mass change. Our results indicate that water vapor, solar radiation and litter quality controlled decomposition and changes in litter chemistry during rainless seasons. Many regions worldwide experience transient periods without rainfall, and more land area is expected to undergo reductions in rainfall as a consequence of climate change. Therefore, absorption of water vapor might play a role in decomposition and nutrient cycling in an increasing number of ecosystems.     

Parental care trade‐offs in the inter‐brood phase in Barn Swallows Hirundo rustica

In seasonal environments with limited time and energy resources, double‐brooded birds face trade‐offs in the timing of their two reproductive attempts and in the effort allocated to the first and the second broods. In the Barn Swallow Hirundo rustica a long care period for the first brood enhances the survival of first‐brood chicks, but also delays the start of the second brood, which in turn reduces the survival prospects of second‐brood chicks. Probably as a response to this trade‐off, double‐brooded Barn Swallows reduce the period of post‐fledging care for first‐brood fledglings. By radiotracking whole families, we investigated the determinants of this behaviour and its consequences for the survival of the first‐brood fledglings. The end of the females’ investment in post‐fledging care of the first brood was related to the beginning of egg synthesis for the second clutch. With the start of egg synthesis, females significantly reduced provisioning rates to the first‐brood fledglings to less than one‐fifth of the previous rates, while the proportion of time they spent foraging remained high. Assuming that the females’ foraging success was constant, we conclude that their energy income was allocated to egg production rather than fledgling provision. Males did not compensate for the females’ reduced feeding rates. Thus the start of egg production for the second clutch had a marked effect on the quantity of food received by first‐brood fledglings. In parallel with the changes in parental behaviour and provisioning rates, we observed a marked drop in the daily survival rate of first‐brood chicks. These results support the hypothesis that females face a strong trade‐off in the allocation of energy to subsequent broods. Energy allocation to a second clutch involves a cost in terms of reduced provisioning, and as a result the survival of first‐brood chicks is compromised. This is probably outweighed by the improved success of an early second brood.     

Cytologic characteristics of endocrine ductal carcinoma in situ of the breast. A case report

BACKGROUND: Endocrine ductal carcinoma in situ is a rare form of ductal carcinoma in situ. It is regarded as a distinct subgroup of mammary carcinoma. However, the cytologic features of endocrine ductal carcinoma in situ have not been previously reported. CASE: A case of endocrine ductal carcinoma in situ exhibited characteristic cytologic findings on a specimen obtained by the scrape method (stained with hematoxylin and eosin and Diff-Quik). CONCLUSION: The cytologic criteria for endocrine ductal carcinoma in situ are sufficiently distinct and are useful for making the diagnosis on fine needle aspiration.     

Determination of high density lipoprotein cholesterol in venous and capillary whole blood

A procedure is presented and evaluated for separation of plasma high density lipoprotein from either capillary or venous whole blood. The lipoprotein is separated by adding 50 microliter of sample to 250 microliter of 0.15 M NaCl solution containing 99.9 g/l polyethyleneglycol 6000, 0.0374 g/l dextran sulfate (Mr 15,000) and 2.6 mM Mg2+. After gentle mixing for a few minutes and standing 10 min at room temperature, mixtures are centrifuged (1,500 g) for 10 min and cholesterol is measured on 200 microliter of supernatant by an enzymatic-colorimetric method. Comparison studies demonstrate a good correlation between high density lipoprotein cholesterol in plasma and capillary or venous whole blood. The procedure is simple, has the advantage of using either K3-EDTA-anticoagulated whole blood, without the need of centrifugation, or capillary whole blood which can also be collected away from the laboratory.     

Evidence that the phytochrome gene family in black cottonwood has one PHYA locus and two PHYB loci but lacks members of the PHYC/F and PHYE subfamilies

The phytochrome photoreceptors play important roles in the photoperiodic control of vegetative bud set, growth cessation, dormancy induction, and cold-hardiness in trees. Interestingly, ecotypic differences in photoperiodic responses are observed in many temperate- zone tree species. Northern and southern ecotypes of black cottonwood (Populus trichocarpa Torr. & Gray), for example, exhibit marked differences in the timing of short-day-induced bud set and growth cessation, and these responses are controlled by phytochrome. Therefore, as a first step toward determining the molecular genetic basis of photoperiodic ecotypes in trees, we characterized the phytochrome gene (PHY) family in black cottonwood. We recovered fragments of one PHYA and two PHYB using PCR-based cloning and by screening a genomic library. Results from Southern analyses confirmed that black cottonwood has one PHYA locus and two PHYB loci, which we arbitrarily designated PHYB1 and PHYB2. Phylogenetic analyses which included PHY from black cottonwood, Arabidopsis thaliana and tomato (Solanum lycopersicum) suggest that the PHYB/D duplications in these species occurred independently. When Southern blots were probed with PHYC, PHYE, and PHYE heterologous probes, the strongest bands that we detected were those of black cottonwood PHYA and/or PHYB. These results suggest that black cottonwood lacks members of the PHYC/F and PHYE subfamilies. Although black cottonwood could contain additional PHY that are distantly related to known angiosperm PHY, our results imply that the PHY family of black cottonwood is less complex than that of other well-characterized dicot species such as Arabidopsis and tomato. Based on Southern analyses of five black cottonwood genotypes representing three photoperiodic ecotypes, substantial polymorphism was detected for at least one of the PHYB loci but not for the PHYA locus. The novel character of the PHY family in black cottonwood, as well as the differences in polymorphism we observed between the PHYA and PHYB subfamilies, indicates that a number of fundamental macro- and microevolutionary questions remain to be answered about the PHY family in dicots.      

牛脾转移因子的提取工艺研究

目的：比较从牛脾中提取活性ＴＦ的不同方法。方法：分别利用Ｌａｗｒｅｎｃｅ－－透析法、Ｌａｗｒｅｎｃｅ－超滤法、超离心－超滤法提取,再以蛋白反应、红外及紫外扫描予以鉴定比较。结果：Ｌａｗｒｅｎｃｅ－超滤法和超离心－超滤法效果较好。结论：工业化生产中应采用Ｌａｗｒｅｎｃｅ－超滤法。     

Functional diversity of reef molluscs along a tropical-to-temperate gradient

Coral Reefs - Global warming is leading to range shifts of marine species, threatening the structure and functioning of ecological communities and human populations that rely on them. The largest...     

Human apolipoprotein a-I natural variants: molecular mechanisms underlying amyloidogenic propensity

Human apolipoprotein A-I (apoA-I)-derived amyloidosis can present with either wild-type (Wt) protein deposits in atherosclerotic plaques or as a hereditary form in which apoA-I variants deposit causing multiple organ failure. More than 15 single amino acid replacement amyloidogenic apoA-I variants have been described, but the molecular mechanisms involved in amyloid-associated pathology remain largely unknown. Here, we have investigated by fluorescence and biochemical approaches the stabilities and propensities to aggregate of two disease-associated apoA-I variants, apoA-IGly26Arg, associated with polyneuropathy and kidney dysfunction, and apoA-ILys107-0, implicated in amyloidosis in severe atherosclerosis. Results showed that both variants share common structural properties including decreased stability compared to Wt apoA-I and a more flexible structure that gives rise to formation of partially folded states. Interestingly, however, distinct features appear to determine their pathogenic mechanisms. ApoA-ILys107-0 has an increased propensity to aggregate at physiological pH and in a pro-inflammatory microenvironment than Wt apoA-I, whereas apoA-IGly26Arg elicited macrophage activation, thus stimulating local chronic inflammation. Our results strongly suggest that some natural mutations in apoA-I variants elicit protein tendency to aggregate, but in addition the specific interaction of different variants with macrophages may contribute to cellular stress and toxicity in hereditary amyloidosis.