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21.
Bersinger NA; Brandenberger A; Berger E; Baumann CK; Birkhauser MH 《Human reproduction (Oxford, England)》1998,13(7):1962-1967
We have previously observed the repeated presence of low but detectable
amounts of the trophoblast marker pregnancy-specific beta1-glycoprotein
(SP1) in the serum of some women undergoing in-vitro fertilization (IVF)
treatment around the time of oocyte retrieval. The occurrence of these
signals seemed to be restricted to a defined group of patients which also
showed a lower pregnancy success rate in a preliminary study. To test our
hypothesis we have analysed 173 consecutive cycles leading to an embryo
transfer. Fifty-four cycles (31%) had a serum SP1 level of at least 0.1
ng/ml between days embryo transfer -5 and embryo transfer (group A). Five
pregnancies were obtained in this group (pregnancy rate = 9.3%), while in
group B, defined by the absence of detectable SP1 before embryo transfer
(119 cycles), 36 ongoing pregnancies were achieved (30.3%). Ten of the 41
pregnancies were achieved in 33 first-time non-pregnant patients undergoing
further attempts during the study period. Again the pregnancy rate was
higher in the first-time group B women (9/23 versus 1/10 for group A).
Patients tended to remain in their groups A or B, the latter being
associated with a better immediate as well as subsequent chance for
pregnancy. Group A cycles had a significantly lower endometrial thickness
two days before oocyte retrieval than group B (P = 0.0011). We postulate
that the presence of an unknown, maternal and progesterone- or follicle
stimulating hormone-independent factor in some patients could stimulate
tonic ectopic SP1 synthesis and at the same time negatively influence
endometrial development.
相似文献
22.
Blind source separation assumes that the acquired signal is composed of a weighted sum of a number of basic components corresponding
to a number of limited sources. This work poses the problem of ECG signal diagnosis in the form of a blind source separation
problem. In particular, a large number of ECG signals undergo two of the most commonly used blind source separation techniques,
namely, principal component analysis (PCA) and independent component analysis (ICA), so that the basic components underlying
this complex signal can be identified. Given that such techniques are sensitive to signal shift, a simple transformation is
used that computes the magnitude of the Fourier transformation of ECG signals. This allows the phase components corresponding
to such shifts to be removed. Using the magnitude of the projection of a given ECG signal onto these basic components as features,
it was shown that accurate arrhythmia detection and classification were possible. The proposed strategies were applied to
a large number of independent 3s intervals of ECG signals consisting of 320 training samples and 160 test samples from the
MIT-BIH database. The samples equally represent five different ECG signal types, including normal, ventricular couplet, ventricular
tachycardia, ventricular bigeminy and ventricular fibrillation. The intervals analysed were windowed using either a rectangular
or a Hamming window. The methods demonstrated a detection rate of sensitivity 98% at specificity of 100% using nearest neighbour
classification of features from ICA and a rectangular window. Lower classification rates were obtained using the same classifier
with features from either PCA or ICA and a rectangular window. The results demonstrate the potential of the new method for
clinical use. 相似文献
23.
Youssef AR Shen CR Lin CL Barker RN Elson CJ 《Clinical and experimental immunology》2005,139(1):84-89
New Zealand Black (NZB) mice spontaneously develop autoimmune haemolytic anaemia (AIHA). Here the effect of injecting NZB mice with plasmids encoding IL-4 (pIL-4) or IL-10 (pIL-10) on NZB disease was tested. Both constructs delayed the development of anaemia as judged by increased haematocrit values as compared with controls, but neither altered the IgG1 to IgG2 red blood cell (RBC) bound autoantibody levels. The increased haematocrit value was associated temporally with increased RBC bound IgG in NZB mice treated with pIL-10, but not pIL-4. By contrast, up-regulation of splenic macrophage FcgammaRIIb2 mRNA was associated temporally with increased haematocrit values in NZB mice given pIL-4. However, no such increase occurred in NZB mice that inhaled a peptide containing a dominant T-cell epitope, although this treatment is known to bias the autoimmune response towards Th2 and to reduce the severity of anaemia. It is considered that IL-4 treatment, in part, ameliorates NZB anaemia by increasing the expression of the inhibitory FcgammaRIIb2 and thereby reducing the capacity of splenic macrophages to phagocytose autoantibody coated RBC, but that this mechanism does not explain the beneficial effects of the inhaled peptide. 相似文献
24.
Summary The development ofEimeria dispersa Tyzzer, a parasite of bobwhite quail, in Madin-Darby bovine kidney cell cultures was investigated. Excysted sporozoites were inoculated into Leighton tubes containing cell monolayers on glass coverglasses and maintained in minimum essential medium supplemented with heat-inactivated fetal calf serum. Sporozoites became intracellular within 2 h. Sporozoite-shaped schizonts, schizonts with developing merozoites, and mature first-generation schizonts were seen 24 h postinoculation. Intracellular first-generation merozoites, second-generation trophozoites, and early second-generation schizonts containing two nuclei were first observed 72 h postinoculation. Second-generation schizonts containing developing merozoites as well as mature second-generation schizonts were first seen 96h postinoculation. Gametogony was not observed.DM
developing merozoite
- HN
host nucleus
- IM
intracellular merozoite
- M
merozoite
- N
nucleus
- R
refractile body
- RB
residual body
- V
parasitophorous vacuole 相似文献
25.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
26.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
27.
p53 immunoreactivity in hepatocellular adenoma, focal nodular hyperplasia, cirrhosis and hepatocellular carcinoma 总被引:2,自引:0,他引:2
I. OJANGUREN A. ARIZA E.M. CASTELLÀ A. FERNÁNDEZ-VASALO J.L. MATE J.J. NA VAS-PALACIOS 《Histopathology》1995,26(1):63-68
The prolonged half-life of mutant p53 makes feasible its immunocytochemical detection. In order to assess the pathogenetic role of mutant p53 in regenerative and neoplastc liver disease we studied its immunohistochemical expression in cases of hepatic cirrhosis, hepatocellular carcinoma (HCC), cirrhosis with areas of HCC, hepatocellular adenoma and focal nodular hyperplasia. The study included needle and wedge biopsies of 50 cirrhotic livers, 59 HCCs (36 of them with associated cirrhosis), six adenomas and two focal nodular hyperplasias. Sixty-five HCC fineneedle cytology specimens were also included in the study. There was no immunohistochemical evidence of mutant p53 expression in any of the cases of cirrhotic liver (except for one instance associated with HCC) adenoma or focal nodular hyperplasia. In contrast p53 was detected in 8.5% of HCC cases in the biopsy series and 24% of HCC cases in the fine needle aspiration series. In addition, mutant p53 expression in HCC was positively correlated with tumour grade. According to grade, the distribution of p53 positive immunoreactivity among HCCs was as follows: Grade I-II, 0% of cases in the biopsy series and 9% in the fine needle aspirates; Grade III, 18% in the biopsy series and 55% in the fine needle aspirates; and Grade IV, 40% in the biopsy series. Therefore, mutant p53 expression does not seem to be associated with benign liver lesions but seems to correlate with the progression of HCC through various grades of increasing malignancy. 相似文献
28.
29.
30.
Ouadrhiri Y Pilette C Monteiro RC Vaerman JP Sibille Y 《American journal of respiratory cell and molecular biology》2002,26(3):315-332
Human alveolar macrophages (HAM) express FcalphaR receptors for immunoglobulin (Ig)A which could link humoral and cellular branches of lung immunity. Here, we investigate the effects of polymeric (p-IgA) and secretory (S-IgA) IgA interaction with Fc(alpha)R on lipopolysaccharide (LPS)- and phorbol myristate acetate (PMA)-activated respiratory burst and TNF-alpha release by HAM. Activation of HAM with LPS and PMA increases the respiratory burst and TNF-alpha release through activation of the extracellular signal-related protein kinases 1 and 2 (ERK1/2) pathway, because these effects are inhibited by treatment of HAM with PD98059, a selective inhibitor of mitogen-activated protein (MAP)/ERK kinases (MEK) pathway. S-IgA and p-IgA downregulate the LPS-increased respiratory burst in HAM through an inhibition of ERK1/2 activity. In contrast, p- and S-IgA induce an increase in the respiratory burst of PMA-treated HAM. This effect is associated with an upregulation by IgA of the PMA-induced phosphorylation of ERK1/2 and is also inhibited by PD98059. Moreover, p-IgA and S-IgA enhance TNF-alpha release by HAM through an alternative pathway distinct from ERK1/2. Because LPS is known to activate nuclear factor-kappaB (NF-kappaB) in HAM, we evaluate the effect of IgA on NF-kappaB. Treatment of HAM with LPS, p- and S-IgA, but not PMA, induces NF-kappaB activation through IkappaBalpha phosphorylation and subsequent proteolysis. Antioxidants, namely N-acetylcysteine (NAC) and glutathione (GSH), have no effects on IgA-mediated NF-kappaB nuclear translocation and only a minor and late effect on that of LPS, suggesting that reactive oxygen intermediates (ROI) play a minor role in HAM activation through NF-kappaB. TNF-alpha release by LPS-activated HAM is sensitive to NF-kappaB inhibition and only partly to oxidant scavenging. In contrast, TNF-alpha release by IgA-treated HAM is not dependent on oxidants and only partly dependent on NF-kappaB. Our results show a differential HAM regulation by IgA through both dependent and independent modulation of ERK pathway. In addition, IgA activates NF-kappaB and this effect was independent on oxidants. These data may help to understand the role of IgA in both lung protection and inflammation. 相似文献