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21.
Enrico Bertino Carolina Bisson Claudio Martano Alessandra Coscia Claudio Fabris Giovanna Monti Tiziana Testa Amedeo Conti 《Pediatric allergy and immunology》2006,17(7):484-488
AIM: A positive correlation between maternal and cord-blood IgE levels is well documented for total IgEs, but not for specific IgEs. The difficulty in detecting specific cord-blood IgEs is due to their low concentrations, which hinder their dosage by low-sensitivity methods. The study aimed to correlate maternal and foetal specific IgEs against individual cow's milk proteins, detected by highly sensitive and specific techniques. METHODS: Cow's milk specific IgE detection was performed by chemiluminescence on 52 specimens of maternal and cord blood after cow's milk protein separation by 1D and 2D gel electrophoresis. Cow's milk protein (CMP) antigens were identified by mass spectrometry techniques. RESULTS: Specific IgEs for CMPs were found in 25/52 (48.1%) of maternal sera and in 19/52 (37%) of cord-blood sera. In order of decreasing frequency, the proteins found were BSA, IgG heavy chain, caseins and, in a single case, b-lactoglobulin. Positive cord-blood sera in all cases corresponded to a positive maternal result, and maternal and foetal immunoreactivity patterns were closely correlated. Moreover, in no case was there a positive cord-blood response with a negative maternal response. CONCLUSION: The study demonstrates a close relationship between maternal and cord-blood specific IgE patterns. The phenomenon observed could provide a model to elucidate the general production method of foetal IgEs, which might only be produced in the presence of both the corresponding maternal IgE and the related allergen. 相似文献
22.
BCSH Blood Transfusion Task Force D. Voak R. Cann R. D. Finney K. Foreman S. M. Knowles R. Mitchell J. A. F. Napier P. K. Phillips A. J. Rejman A. H. Waters J. K. Wood R. M. Hutchinson A. J. Bell J. K. M. Duguid J. M. Hows K. Jestice D. E. Pegg N. G. Testa 《Transfusion medicine (Oxford, England)》1994,4(2):165-172
SUMMARY. There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long-term bone marrow culture are alluded to but these are still in a research phase. 相似文献
23.
Modulatory effect of prolactin on the resting and mitogen-induced activity of T, B, and NK lymphocytes 总被引:4,自引:0,他引:4
Lina Matera Alessandra Cesano Graziella Bellone Emanuela Oberholtzer 《Brain, behavior, and immunity》1992,6(4):409-417
Prolactin (PRL) has been shown to contribute to the development of lymphoid tissues and maintenance of physiological immune function. Here we show that the role of the hormone extends to the control of the effector phase of the immune response. In addition to triggering resting lymphocytes to cell division, the hormone can also control the magnitude of their response to polyclonal stimuli. Concentrations of PRL in the physiological range increased the [3H]thymidine, [3H]uridine, and [3H]leucine incorporation of unstimulated NK cells cultured in serum-free conditions. The same concentrations of the hormone increased the response of NK, T, and B cells to the mitogenic stimuli interleukin 2 (IL2), phytohemagglutinin (PHA), and staphylococcus aureus cowan, respectively, the effect being maximally evident in the presence of suboptimal concentrations of the mitogens. By contrast concentrations of PRL five- to tenfold the physiological levels inhibited the mitogenic response to IL2 and PHA. These data indicate a double-faceted regulatory role of this hormone in vivo. 相似文献
24.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
25.
Inhibition by N-acetylcysteine of carcinogen-DNA adducts in the tracheal epithelium of rats exposed to cigarette smoke 总被引:1,自引:0,他引:1
Izzotti Alberto; Balansky Roumen; Scatolini Leonardo; Rovida Alessandra; De Flora Silvio 《Carcinogenesis》1995,16(3):669-672
The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. 32P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/108 nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts. 相似文献
26.
Pierpaolo Sileri Vito Maria Stolfi Giampiero Palmieri Alessandra Mele Alessandro Falchetti Sara Di Carlo Achille Lucio Gaspari 《Journal of gastrointestinal surgery》2007,11(12):1662-1668
Stapled hemorrhoidopexy is widely accepted to treat hemorrhoids, but serious complications have been reported. In this prospective
audit, we correlated clinical outcome with pathological findings. From January 2003 to April 2007, 94 patients underwent hemorrhoidopexy.
Macroscopic appearance of the specimen (shape, size, and depth) was recorded. Microscopically, the presence of columnar, transitional,
and squamous epithelium, the involvement of circular/longitudinal smooth muscle, and features of mucosal prolapse were assessed.
Clinical outcome was evaluated by a validated questionnaire. Postoperative pain, secretion, and bleeding durations were 12.7 +/− 10.6,
5.6 +/− 9.6, and 6.3 +/− 8.4 days. Patient’s return to work averaged 16.7 +/− 10.7 days. Fissure, skin tags, and anal strictures
were observed in 23.4%. Seven patients experienced pain for a significantly longer period of time. All specimens contained
columnar mucosa, but 29.8% contained columnar and transitional epithelium and 12.8% contained columnar, anal transitional,
and stratified squamous epithelium. Smooth muscle was observed in 62.7%. Pain was significantly increased if transitional
epithelium was present in the specimen. No correlation or differences were observed if smooth muscle was present, although
postoperative bleeding was more frequent. Hemorrhoidopexy is safe and effective. The specimen should always be sent for pathology
examination. Only columnar epithelium should be present and, although the presence of smooth muscle does not influence the
outcome in terms of functional results, its presence may play a role in postoperative bleeding.
Presented as poster at the Digestive Disease Week, May 2007, Washington, USA 相似文献
27.
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29.
Randomised prospective study on renal effects of two different contrast media in humans: protective role of a calcium channel blocker 总被引:6,自引:0,他引:6
Contrast media affect renal hemodynamics. Hyperosmolality is regarded as the major factor responsible for renal hemodynamic changes. In this study, the role of osmolality was evaluated in 30 hospitalized patients without risk factors during intravenous pyelography. Contrast media with low and high osmolality were used. In addition, nifedipine was administered before infusion of high-osmolality contrast to evaluate the role of calcium ions in radiocontrast-induced changes of renal hemodynamics. Hyperosmolar contrast reduced renal plasma flow and glomerular filtration rate. Calcium channel blocker prevented changes of renal hemodynamics. Hyperosmolality appears the most likely factor affecting renal hemodynamics during hyperosmolar radiocontrast infusion. Calcium channel blocker may prevent renal changes due to hyperosmolar medium. 相似文献
30.
Residual damage in haemopoietic progenitor cell populations, spleen and granulocyte-macrophage colony-forming cells (CFU-S and GM-CFC) was detected in mice after 15 daily fractions where the dose per fraction was as low as 0.1 Gy. The injury was dose-dependent and after higher total fractionated doses of 7.5-10 Gy the CFU-S population recovered to about 50% of control between 2 and 12 months after irradiation. Residual damage was also detected in the stroma, in the form of reduced numbers of fibroblastoid colony-forming cells and of CFU-S in ossicles under the kidney capsule. The response to a second course of 15 fractions, given 3 weeks after the end of the first course, was similar and additive to the response to the first course in the short term. However, in the long term, recovery levels were similar after either one or two courses. 相似文献