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1.
Glucoraphasatin is an atypical glucosinolate mainly found in Raphanus sativus roots and sprouts. This review focuses on the chemistry, the occurrence, and the biological properties of glucoraphasatin. 相似文献
2.
Márcia M. Medeiros Henrique B. da Silva Aramys S. Reis Renato Barboza Joanne Thompson Maria Regina D'Império Lima Cláudio R. F. Marinho Carlos E. Tadokoro 《PloS one》2013,8(11)
It is postulated that accumulation of malaria-infected Red Blood Cells (iRBCs) in the liver could be a parasitic escape mechanism against full destruction by the host immune system. Therefore, we evaluated the in vivo mechanism of this accumulation and its potential immunological consequences. A massive liver accumulation of P. c. chabaudi AS-iRBCs (Pc-iRBCs) was observed by intravital microscopy along with an over expression of ICAM-1 on day 7 of the infection, as measured by qRT-PCR. Phenotypic changes were also observed in regulatory T cells (Tregs) and dendritic cells (DCs) that were isolated from infected livers, which indicate a functional role for Tregs in the regulation of the liver inflammatory immune response. In fact, the suppressive function of liver-Tregs was in vitro tested, which demonstrated the capacity of these cells to suppress naive T cell activation to the same extent as that observed for spleen-Tregs. On the other hand, it is already known that CD4+ T cells isolated from spleens of protozoan parasite-infected mice are refractory to proliferate in vivo. In our experiments, we observed a similar lack of in vitro proliferative capacity in liver CD4+ T cells that were isolated on day 7 of infection. It is also known that nitric oxide and IL-10 are partially involved in acute phase immunosuppression; we found high expression levels of IL-10 and iNOS mRNA in day 7-infected livers, which indicates a possible role for these molecules in the observed immune suppression. Taken together, these results indicate that malaria parasite accumulation within the liver could be an escape mechanism to avoid sterile immunity sponsored by a tolerogenic environment. 相似文献
3.
L Kolster C Jensen A Bruni L Mietto G Toffano S Norn 《Biochimica et biophysica acta》1987,927(2):196-202
The effect of lysophosphatidylserine on immunological histamine release has been studied in rat peritoneal mast cells actively sensitized with horse serum and in human basophils challenged with anti-IgE. In contrast to other lysophospholipids, lysophosphatidylserine enhances the immunological histamine release in rat mast cells. The effect shows the kinetics of a saturable process with an apparent Km for lysophosphatidylserine of 0.26 microM. A similar Km value (0.21 microM) is found when measuring the non-immunological histamine release activated by lysophosphatidylserine plus nerve growth factor. A comparison with phosphatidylserine shows that a half-maximal response to lysophosphatidylserine occurs at a concentration 4-times lower. In addition, the magnitude of the response is higher. At variance with rat mast cells, lysophosphatidylserine does not influence the histamine release elicited by immunological and non-immunological stimuli in human basophils. The histamine secretion in these cells is instead affected by a calcium ionophore or tetradecanoylphorbolacetate, a compound producing activation of protein kinase C. 相似文献
4.
Dielectric properties of Artemia cysts at low water contents. Evidence for a percolative transition. 总被引:2,自引:1,他引:1
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Cellular cysts of the crustacean Artemia provide a useful model for studies on water-dependent mechanisms in cellular function because they can undergo reversible cycles of dehydration-rehydration. We explored their dielectric behavior over the frequency range of 10 kHz to 1 MHz, at water contents between near zero and 0.5 g H2O/g dry weight (g/g). The dc conductivity and static dielectric permittivity were evaluated from electrostatic analysis of data obtained with a three-layered capacitor. Below cyst hydrations of 0.05 g/g, negligible dielectric response was observed at all frequencies. Between 0.05 and 0.25 g/g the permittivity increased sharply then reached a near plateau up to cyst hydrations close to 0.35 g/g, above which a second abrupt increase occurred. Values for the dielectric loss (tan delta) exhibited frequency-dependent peaks over the hydration range of 0.05-0.3 g/g, followed by an abrupt increase near 0.35 g/g, an hydration at which metabolism is first initiated in this system. These hydration-dependent dielectric changes are compared with previous studies on the biology and physics of this system, and evaluated by a model involving percolative ionic (likely protonic) conduction. Percolative behavior is characterized by a sharp increase in conductivity at a critical threshold of hydration (hc) according to a power law in which the exponent, t, equals 1.65 for a three-dimensional infinite lattice. For the Artemia cyst, t = 1.64 above hc = 0.35 g/g, which is in excellent agreement with theory. These results are compared to similar studies on lysozyme which also exhibits percolative behavior connected with the onset of biological function. 相似文献
5.
An endpoint enzymatic assay for fructose 2,6-bisphosphate performed in 96-well plates 总被引:1,自引:0,他引:1
An endpoint enzymatic assay for fructose 2,6-bisphosphate based on the ability of the compound to stimulate pyrophosphate 6-phosphofructo-1-kinase and performed in a 96-well plate is reported here. The method presents a low detection limit and a high sensitivity that could be further improved; moreover, the use of 96-well plates greatly increases the number of samples that can be simultaneously assayed. 相似文献
6.
Sertoli and Leydig cell numbers and gonadotropin receptors in rat testis from birth to puberty 总被引:4,自引:0,他引:4
Marino Bortolussi Renato Zanchetta Paola Belvedere Lorenzo Colombo 《Cell and tissue research》1990,260(1):185-191
Summary In testes of rats from 2 to 60 days of age, we examined the number of Sertoli cells (SC) and Leydig cells (LC) as well as the binding of radioiodinated gonadotropins to frozen sections and homogenates. The number of SC per testis increased only during the first 2 postnatal weeks, whereas that of LC was stable up to days 7–10 and increased thereafter. The uptake of 125I-labelled human follicle-stimulating hormone (125I-FSH) to frozen sections was confined to sex cords or seminiferous tubules, while that of 125I-labelled human choriogonadotropin (125I-hCG) matched the distribution of LC in the interstitium. High affinity receptors for FSH and hCG were found in homogenates at all stages studied. The number of FSH receptors per testis increased steadily, whereas that of hCG receptors was low until days 7–10 and rose afterwards. Thus, SC in rat testis appear to proliferate in the presence of fetal LC during the first 2 postnatal weeks and to differentiate concomitantly with the emergence of the adult LC generation after day 10. The complement of FSH receptors in SC remains constant as they proliferate and increases after day 21 as they differentiate. The hCG receptor number is relatively fixed in each LC generation, being higher in adult compared to fetal LC. 相似文献
7.
Renato V. La Rocca Cy A. Stein Romano Danesi Charles E. Myers 《The Journal of steroid biochemistry and molecular biology》1990,37(6):893-898
Suramin, a polyanionic compound originally synthesized for use as an antiparasitic agent, has recently entered clinical trials for the treatment of a variety of human cancers refractory to conventional modalities of therapy. This is based on suramin's ability to bind and to inactivate growth factor and enzyme systems critical to cellular homeostasis and proliferation. In addition, this compound possesses adrenocorticolytic properties in vivo and exerts significant cytostatic and cytocidal effects against a variety of human tumor cell lines in vitro. Pilot studies using suramin have thus far been conducted in adrenocortical carcinoma, prostate cancer refractory to conventional hormonal manipulation and nodular lymphomas. 相似文献
8.
Arsenio Corrado Negrini Renato Ariano Guiseppina Delbono Antonio Ebbli Antonio Quaglia Daniele Arobba 《Aerobiologia》1992,8(3):355-358
Summary The authors examined 734 sensitised patients living in four localities in Liguria (Genoa, Savona, Pietra Ligure and Sanremo). The commonest source of sensitisation (62.7%) was Urticaceae (Parietaria), followed by Poaceae (52.5%) andOlea europaea L. (24.0%). A survey of airborne pollens revealed a greater presence of Urticaceae and Poaceae in Genoa and of Oleaceae in Pietra Ligure and Sanremo. 相似文献
9.
10.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献