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排序方式: 共有225条查询结果,搜索用时 31 毫秒
41.
Cassano M Cassano P Ciprandi G 《Journal of biological regulators and homeostatic agents》2011,25(2):299-301
Respiratory viral infections may worsen bronchial hyperreactivity. However, there is no data on the possible role of recurrent infectious rhinitis in nose hyperreactivity. This study was therefore designed to investigate whether subjects suffering from recurrent common cold have nasal hyperreactivity, assessed by histamine nasal challenge. This study included a group of 40 patients (19 males, mean age 34.1 years) with history of at least five episodes of common cold in the previous year, but without documented allergy, and twenty healthy subjects (8 males, mean age 32.3 years) were enrolled as control group, all of whom were non-allergic. Nasal provocation test with histamine was performed in all subjects. Nasal provocation test with histamine induced a 200% increase in nasal resistance after provocation in 24 (60%) patients suffering from recurrent viral rhinitis. No normal subject had an increase >180% in nasal resistance. There was a significant difference between the patient group and the control group (p<0.05). In conclusion, this study shows that nasal hyperreactivity might be a sequela of recurrent common cold. Further studies should be conducted to confirm this preliminary finding. 相似文献
42.
Cassano N Mastrandrea V Principi M Loconsole F De Tullio N Di Leo A Vena GA 《Journal of biological regulators and homeostatic agents》2011,25(2):285-289
One of the problems possibly related to the use of biological agents targeting tumor necrosis factor (TNF)-alpha is the increased risk of infections, including the activation of hepatitis B virus (HBV). HBV activation can occur in carriers of hepatitis B surface antigen (HBsAg), but the risk may also involve the HBsAg-negative (anti-HBc ± anti-HBs) occult carriers. Precise data on the safety of anti-TNF and/or other immunosuppressive drugs in HBV occult carriers are not available. We performed a retrospective analysis of 62 psoriatic patients with occult HBV infection treated with anti-TNF biological agents over a period of approximately 4 years: 44 subjects were treated with etanercept, 8 with infliximab and 10 with adalimumab. During the observational treatment period, no signs of HBV activation were observed. Only in one patient the reappearance of HBsAg, without detectable HBV-DNA, was noted before retreatment with etanercept and after 10 months from discontinuation of the previous course. In this patient etanercept was re-administered in association with lamivudine without any adverse event. Our results suggest the overall safety of treatment with anti-TNF drugs in HBV occult carriers, although a careful and constant monitoring of virological markers is required in such patients during treatment with anti-TNF drugs in order to have an early recognition of viral reactivation. 相似文献
43.
Guaragnella N Antonacci L Passarella S Marra E Giannattasio S 《Biochemical Society transactions》2011,39(5):1538-1543
The use of non-mammalian model organisms, including yeast Saccharomyces cerevisiae, can provide new insights into eukaryotic PCD (programmed cell death) pathways. In the present paper, we report recent achievements in the elucidation of the events leading to PCD that occur as a response to yeast treatment with AA (acetic acid). In particular, ROS (reactive oxygen species) generation, cyt c (cytochrome c) release and mitochondrial function and proteolytic activity will be dealt with as they vary along the AA-PCD time course by using both wild-type and mutant yeast cells. Two AA-PCD pathways are described sharing common features, but distinct from one another with respect to the role of ROS and mitochondria, the former in which YCA1 acts upstream of cyt c release and caspase-like activation in a ROS-dependent manner and the latter in which cyt c release does not occur, but caspase-like activity increases, in a ROS-independent manner. 相似文献
44.
Ficarra S Russo A Stefanizzi F Mileto M Barreca D Bellocco E Laganà G Leuzzi U Giardina B Galtieri A Tellone E 《The Journal of membrane biology》2011,242(1):31-39
Palytoxin (PTX) is classified as one of the most powerful marine biotoxins (of high molecular weight and no protein origin) because it is able to interact strongly with important cellular structures influencing their function in different biological processes. This study of the effects of PTX on red blood cells (RBC) extends the knowledge about its toxicity, which concerns not only the well-known action on Na(+)/K(+)-ATPase but also band 3 protein (B3 or AE1), the role of which is essential for anion transport and for the structure, function, and metabolic integrity of the erythrocyte. The effects of PTX on RBC can be summarized as follows: it alters the anionic flux and seriously compromises not only CO(2) transport but also the metabolic modulation centered on the oxy-deoxy cycle of hemoglobin; it stabilizes the plasma membrane by preventing lipid peroxidation; and its effect does not lead to activation of caspases 3 and 8. From what is reported in steps 2 and 3, and on the basis of the results obtained on hemolysis, methemoglobin levels, and phosphatase activity, an increase of the reducing power of the erythrocytes (RBC) in the presence of PTX clearly emerges. The results have enabled us to outline some metabolic adaptations induced in the RBC by PTX. 相似文献
45.
46.
Enrica Ciucci Pamela Calussi Ersilia Menesini Alessandra Mattei Martina Petralli Simone Orlandini 《International journal of biometeorology》2011,55(3):327-337
This study aimed to analyze the impact of winter weather conditions on young children’s behavior and affective states by examining
a group of 61 children attending day-care centers in Florence (Italy). Participants were 33 males, 28 females and their 11
teachers. The mean age of the children at the beginning of the observation period was 24.1 months. The day-care teachers observed
the children’s behavioral and emotional states during the morning before their sleeping time and filled in a questionnaire
for each baby five times over a winter period of 3 weeks. Air temperature, relative humidity, air pressure and solar radiation
data were collected every 15 min from a weather station located in the city center of Florence. At the same time, air temperature
and relative humidity data were collected in the classroom and in the garden of each day-care center. We used multilevel linear
models to evaluate the extent to which children’s emotional and behavioral states could be predicted by weather conditions,
controlling for child characteristics (gender and age). The data showed that relative humidity and solar radiation were the
main predictors of the children’s emotional and behavioral states. The outdoor humidity had a significant positive effect
on frustration, sadness and aggression; solar radiation had a significant negative effect only on sadness, suggesting that
a sunny winter day makes children more cheerful. The results are discussed in term of implications for parents and teachers
to improve children’s ecological environment. 相似文献
47.
We studied the relationship between differentiation, transformation, and uPA production in a system of rat thyroid cells in vitro. The fully differentiated FRTL5 cells did not produce detectable amounts of uPA, even after stimulation with phorbol esters, potent inducers of uPA expression. All the other cell lines (i.e., FRT, cells which have lost the characteristics of the differentiated thyroid cells; 1-5 G and FRA, transformed cells derived from rat thyroid tumors) produced uPA, the 1-5 G line being the highest producer. Also the FRTL line became positive for uPA production after viral transformation (clone KM4). The lack of uPA expression in FRTL5 cells was not due to the presence of inhibitors and these cells did not produce an inactive molecule, as shown by immunoprecipitation with anti-uPA antibody. However, in FRTL5 cells Northern analysis showed the presence of a small amount of uPA-specific mRNA that increased appreciably after phorbol ester stimulation. In conclusion, in our system uPA expression was a property of undifferentiated and transformed cells; in fully differentiated cells uPA expression was switched off by a still unclear mechanism. 相似文献
48.
Influence of cetylpyridinium chloride on the ultrastructural appearance of sulphated glycosaminoglycans in human colonic mucosa 总被引:1,自引:0,他引:1
F. Malchiodi Albedi A. M. Cassano F. Ciaralli G. Donelli A. Giuliani P. Mingazzini V. Marinozzi 《Histochemistry and cell biology》1988,89(4):397-401
Summary The effect of adding cetylpyridinium chloride to the fixative on the preservation of sulphated glycosaminoglycans (SGs) was studied in human normal colonic mucosa. SGs were visualized at the ultrastructural level through the application of Spicer's High Iron Diamine (HID) technique followed by a post-fixation with potassium ferrocyanide-reduced osmium tetroxide. SGs were mainly localized in basement membranes of epithelium and capillary wall and along collagen fibers. The morphology of the reactive sites depended on the presence of cetylpyridinium chloride, SGs being granular in absence of the salt and more or less elongated when cetylpyridinium chloride was added to the fixative.We suggest that the use of cetylpyridinium chloride during fixation may help to preserve SG molecule at the ultrastructural level. 相似文献
49.
Five rat thyroid cell lines were tested for the expression of the cell surface receptor for urokinase type plasminogen activator (uPA). All tested lines were found to bind uPA, but transformed 1-5G and Ki-Mol cells, which are also high uPA producers, bound at least ten times more uPA, as compared to non-producers, 'normal' TL5 cells. Moreover, it was possible to remove membrane-bound uPA by treating the cells with phosphatidylinositol-specific phospholipase C, suggesting that rat uPAR, like its human counterpart, is linked to the membrane by a glucosyl-phosphatidylinositol anchor. The specificity of the binding was tested by competition with three different synthetic peptides corresponding to amino acids 14-37 of human, rat and mouse uPA. The results indicate also that the receptor binding region of rat uPA is located within the growth factor domain of the molecule and that its expression may be dependent on the transformed state of the cells. 相似文献
50.