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21.
The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor. 相似文献
22.
A historic overview including the European, American, Asian, and African continents is given on attitudes toward and the handling of humans with congenital malformations in ancient cultures and on pertinent customs in some prehistoric peoples. Figures of early works of art showing malformed individuals are presented testifying to this worldwide and timeless problem of humankind. In parallel, analogous patient photographs from our hospital before and after reconstructive surgery are shown. Philosophies of ancient Greece, rome, and China on the subject of malformed infants essentially did not differ from the known attitudes of the less developed tribes in Europe and pre-Columbian America, although the means of elimination of unwanted offspring were rather passive (exposure) than active (manual killing). A radical change in attitudes and practices occurred with the spread of the Christian religion and its political installment in Europe. The care for the underprivileged including the malformed ones was considered a Christian duty to be performed with compassion and love. In our century, the clocks have been and apparently are turned back again. Atheistic and Darwinian influences, political atheism, and the belief in "higher ethics" issued by "superman" have led to a relapse into barbarism, also within the medical system. We, as craniofacial surgeons, are privileged to have the means to turn the clocks forward again by rehabilitating the physically most underprivileged: those with conspicuous craniofacial malformations. The necessary techniques exist and are applied, as the figures of patients from our hospital demonstrate, but the will and the emotional strength for their consequent application require more than our hands. 相似文献
23.
HF Jeejeebhoy 《Canadian Metallurgical Quarterly》1977,35(2):161-169
Lymphocytes from 10 patients with breast carcinoma were seeded in autologous serum, on autochthonous tumour cells and allogeneic tissue-cultured breast tumour cell lines. In 4 patients, the anti-tumour cell cytotoxicity against at least one of 3 breast tumour cell lines differed significantly from that against autochthonous tumour cells. Further study of these 4 individuals (using their previously frozen lymphoid cells and sera) showed that these differences occurred because serum which decreased ("blocked") lymphocyte anti-tumour cytotoxicity when applied to one tumour cell line, could either have no effect or potentiate it when applied to another, without any consistent pattern vis-à-vis target-cell susceptibility to these different humoral effects. 相似文献
24.
Origin and Processing Methods Slightly Affect Allergenic Characteristics of Cashew Nuts (Anacardium occidentale) 下载免费PDF全文
Marit Reitsma Shanna Bastiaan‐Net Lutske Sijbrandij Evelien de Weert Stefano Sforza Roy Gerth van Wijk Huub F. J. Savelkoul Nicolette W. de Jong Harry J. Wichers 《Journal of food science》2018,83(4):1153-1164
The protein content and allergen composition was studied of cashews from 8 different origins (Benin, Brazil, Ghana, India, Ivory Coast, Mozambique, Tanzania, Vietnam), subjected to different in‐shell heat treatments (steamed, fried, drum‐roasted). On 2D electrophoresis, 9 isoforms of Ana o 1, 29 isoforms of Ana o 2 (11 of the acidic subunit, 18 of the basic subunit), and 8 isoforms of the large subunit of Ana o 3 were tentatively identified. Based on 1D and 2D electrophoresis, no difference in allergen content (Ana o 1, 2, 3) was detected between the cashews of different origins (P > 0.5), some small but significant differences were detected in allergen solubility between differently heated cashews. No major differences in N‐ and C‐terminal microheterogeneity of Ana o 3 were detected between cashews of different origins. Between the different heat treatments, no difference was detected in glycation, pepsin digestibility, or IgE binding of the cashew proteins. 相似文献
25.
DA Hullett MT Cantorna C Redaelli J Humpal-Winter CE Hayes HW Sollinger HF Deluca 《Canadian Metallurgical Quarterly》1998,66(7):824-828
BACKGROUND: 1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. METHODS: To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. RESULTS: The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. CONCLUSION: These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection. 相似文献
26.
DJ Kereiakes AM Lincoff DP Miller JE Tcheng CF Cabot KM Anderson HF Weisman RM Califf EJ Topol 《Canadian Metallurgical Quarterly》1998,97(9):857-864
BACKGROUND: Recent studies indicate that eradication of Helicobacter pylori might prevent peptic ulcer formation in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs). On the other hand, gastric adaptation after repeated exposures to aspirin (ASA) is well documented but the influence of H. pylori on this process remains to be elucidated. AIM: To compare gastric damage and adaptation following repeated exposures to ASA in a group of patients with H. pylori infection, before and after eradication of the bacterium, and in H. pylori-negative controls. METHODS: Eight healthy volunteers without H. pylori infection and eight patients with duodenal ulcer (DU) history and H. pylori infection before and after H. pylori eradication were given ASA 2 g/day for a period of 14 days. Mucosal damage was evaluated by endoscopy and histology of biopsy samples. Gastric microbleeding, DNA synthesis in the gastric mucosa and mucosal expression, as well as luminal content of transforming growth factor-alpha (TGFalpha) were determined on days 0, 3, 7 and 14 of the ASA course. RESULTS: In all patients aspirin-induced gastric damage reached a maximum on day 3. In H. pylori-positive patients, this damage was maintained at a similar level up to day 14, whereas in H. pylori-negative controls and H. pylori-eradicated patients this damage significantly lessened on day 14 and was accompanied by elevated DNA synthesis as well as increased mucosal expression and luminal release of TGFalpha. 相似文献
27.
Although myelin basic protein (MBP)-recognizing T cells are not readily obtained after immunization of BALB/c mice with MBP (reflecting the BALB/c resistance to actively induced experimental autoimmune encephalomyelitis (EAE)), they can be expanded and cloned after several rounds of in vitro culture. The majority of BALB/c-derived clones recognize an epitope defined by MBP peptide 59-76. When transferred to naive BALB/c recipients, these clones cause classical EAE, with characteristic inflammation and demyelination of the central nervous system (CNS). We previously showed that two related clones recognizing a minor epitope, defined by MBP peptide 151-168, cause inflammation and demyelination preferentially of the peripheral nervous system (PNS). Because MBP has alternatively spliced isoforms, residues 151-168 are not present contiguously in all MBP isoforms. In order to determine whether induction of PNS disease is idiosyncratic to these sister clones, or related to their properties of epitope recognition, an independent T-cell line with similar recognition properties was studied. Clone 116F, derived from a BALB/c shiverer mouse, expresses a different T-cell receptor (TCR), with distinct TCR contact residues, but like the previously described T cells, this clone requires residues from both exons 6 and 7 for optimal stimulation. When adoptively transferred to BALB/c recipients, this clone preferentially induces disease of the PNS. A control BALB/c shiverer-derived MBP 59-76-recognizing clone, in contrast, induces CNS disease. These data strongly suggest that the site of disease initiation may correlate with epitope recognition, particularly when alternative isoforms are involved. 相似文献
28.
SM Haslam GC Coles EA Munn TS Smith HF Smith HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(48):30561-30570
Structural studies on the N-linked oligosaccharides of Haemonchus contortus, an economically important nematode that parasitizes domestic ruminants, have revealed core fucosylation of a type not previously observed in any eukaryotic glycoprotein. Mass spectrometric analyses were performed on detergent extracts of homogenized adult H. contortus and on purified H11, a glycoprotein isolated from intestinal brush borders which has been previously shown to be an effective vaccine antigen. The major N-linked glycans identified in the present study have up to three fucose residues attached to their chitobiose cores. The fucoses are found at the 3- and/or 6-positions of the proximal GlcNAc and at the 3-position of the distal GlcNAc. The latter substitution is unique in N-glycans. Most anti-H11 monoclonal antibodies are known to recognize carbohydrate epitopes, and it is possible that the newly discovered multifucosylated core structures are highly immunogenic in this glycoprotein. 相似文献
29.
30.