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11.
A factor shed by lymphoblastoid cell lines of HLA-B27 positive patients with ankylosing spondylitis, specifically modifies the cells of HLA-B27 positive normal individuals.
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P Orban J S Sullivan A F Geczy L I Upfold N Coulits H V Bashir 《Clinical and experimental immunology》1983,53(1):10-16
Epstein-Barr virus transformed lymphoblastoid cell lines from HLA-B27 positive individuals with ankylosing spondylitis (B27+AS+) release, into the culture medium, a factor capable of specifically modifying the HLA-B27 positive lymphocytes of normal individuals (B27+AS-); this modification results in a phenotypic change similar to that seen on B27+AS+ lymphocytes. This lymphoblastoid cell line derived factor appears to be physically and functionally similar to a factor present in the culture filtrate of certain Klebsiella isolates. Biogel P-100 chromatography of the material released from the cell line indicated a mol.wt of 25,000-30,000, similar to that of the Klebsiella derived factor. Chromatofocusing on a PBE 94 column revealed that cell line derived factor had an isoelectric point of 5.5 (cf. pI 5.4 for the Klebsiella derived factor). Immunoadsorption experiments suggest that the factor from the B27+AS+ cell line shares antigenic determinants with a cell surface component present on certain Klebsiella isolates. These results will form the basis for future studies on the nature of the interaction between HLA-B27 and certain enteric organisms and their products. A better understanding of this association should elucidate some of the early events in the pathogenesis of the seronegative arthropathies. 相似文献
12.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
13.
Permanent impairment of embryo development by hydrosalpinges 总被引:6,自引:9,他引:6
Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy
outcome for in-vitro fertilization (IVF) and improvement following surgical
treatment. We compared the effect of hydrosalpinx on pregnancy outcome in
286 patients having 348 IVF cycles and followed the development of
untransferred embryos for 7 days to determine if hydrosalpinges affect
oocyte quality or embryo development. The delivery rate per retrieval was
significantly lower for patients with hydrosalpinx, but was restored by
surgical treatment to that of patients without hydrosalpinx. However, the
implantation rate per embryo transferred and normal blastulation of
untransferred embryos, which were significantly decreased in patients with
hydrosalpinx, and growth arrest and degeneration of untransferred embryos,
which were significantly increased compared to patients without
hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We
conclude that surgical treatment of hydrosalpinges decreases early
pregnancy loss and improves pregnancy outcome, possibly by diminishing
reversible deleterious effects exerted on the endometrium. As we have seen
in our laboratory, hydrosalpinges may have a permanent negative influence
on ovarian function, follicular development and oocyte quality since
implantation of transferred embryos and normal blastulation of
untransferred embryos remain low, and in-vitro growth arrest and
degeneration remain high despite surgical treatment of hydrosalpinges.
相似文献
14.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
15.
16.
17.
Complex and simple coronary artery stenoses: a new way to interpret coronary angiograms based on morphologic features of lesions 总被引:1,自引:0,他引:1
For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms. 相似文献
18.
双—对二甲氨基苯甲醛缩二胺类希夫碱合成、表征及抗菌活性 总被引:9,自引:1,他引:8
目的:合成双-对二甲氨基苯甲醛缩二胺类希夫碱,并对其抗菌活性进行研究。方法:以对二甲氨基苯甲醛和二胺类为原料,经缩合反应,制得4种相应希夫碱。结果:结构经元素分析、红外光谱、核磁共振谱确定,4种化合物均未见文献报道,抗菌活性测试表明,它们具有一定抗菌活性。结论:乙酸是催化剂,对缩合反应有利,希夫碱化合物具有一定抗菌活性。 相似文献
19.
Human Brain Regions Involved in Direction Discrimination 总被引:11,自引:0,他引:11
20.
D K Xiao S Raiguel V Marcar J Koenderink G A Orban 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(24):11303-11306
A recurrent theme in the organization of vertebrate visual cortex is that of receptive fields with an associated "silent" opponency component. In the middle temporal area (area MT), a cortical visual area involved in the analysis of retinal motion in primates, this opponency appears in the form of a region outside the classical receptive field (CRF) that in itself gives no response but suppresses responses to motion evoked within the CRF. This antagonistic motion surround has been described as very large and symmetrically arrayed around the CRF. On the basis of this view, the primary function of the surround has long been thought to consist of simple figure-ground segregation based on movement. We have made use of small stimulus patches to map the form and extent of the surround and find evidence that the surround inhibition of many MT cells is in fact confined to restricted regions on one side or on opposite sides of the CRF. Such regions endow MT cells with the ability to make local-to-local motion comparisons, capable of extracting more complex features from the visual environment, and as such, may be better viewed as intrinsic parts of the receptive field, rather than as separate entities responsible for local-to-global comparisons. 相似文献