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171.
172.
Monika Das Prabir K. Mukhopadhyay Mridula Chowdhury 《Molecular and cellular biochemistry》1994,132(2):91-99
Sugar-binding proteins obtained from the peri-implantation uterine tissue have been thought in recent years to have significant roles in embryo implantation, where carbohydrate moieties of the protein are actively involved. Based on this rationale a mannose-containing glycoprotein/lectin (named uterine agglutinin or UA) was purified by Concanavalin A (Con A) affinity chromatography in a previous study. A modification of the original purification procedure to include a 33% ammonium sulfate fractionation improves the yield of the protein significantly. An alternative purification procedure by Mannan affinity matrix, indicates that apart from containing mannose, UA possesses mannose-binding properties as well.In this paper, we report some of the biochemical and more specifically, the carbohydrate-binding characteristics of UA. The protein is seen to contain mannose-6-phosphate (M-6-P)-binding sites, which is of importance since M-6-P receptors have a large number of biologically significant roles, including that of binding to growth factors.SDS-PAGE, gel filtration chromatography and alkaline PAGE indicate the homogenous nature of the protein with subunit molecular weights of 36 kDa and 19 kDa, and a native size of 64kDa. Amino acid analysis shows glycine, glutamic acid and aspartic acid to be the major constituents.UA is a glycoprotein and shows presence of N-acetyl glucosamine and galactose, apart from mannose.De nove synthesis studies in the presence of tunicamycin show that the carbohydrate moiety of the glycoprotein is attached by N-linkage to the protein. Binding characteristics of the protein is studied quantitatively in which (125I)-labelled lectin is bound to Mannan-Sepharose affinity matrix. The sugar inhibition pattern of this binding shows -methyl mannopyranoside and M-6-P to be equally effective as inhibitors. Scatchard analysis of the binding of UA to (14C)-mannose shows a Ka of 6.43×105 (M–1) and that 1 mole of UA can bind to 8 moles of mannose. The possible role of the protein in implantation has also been discussed.Abbreviations b.w.
body weight
- BSA
Bovine Serum Albumin
- Con A
Concanavalin A
- cpm
counts per minute
- Endo H
endoglycosidase H
- GlcNAc
N-acetyl glucosamine
- Man
mannose
- M-6-P
mannose-6-phosphate
- MEM-deficient
Minimum Essential Medium Eagle-deficient modification
- NaBH4
sodium borohydride
- NaN3
sodium azide
- (NH4)2SO4
ammonium sulphate
- p.c.
post coitum
- PMSF
phenyl methyl sulphonyl fluoride
- PTA
phosphotungstic acid
- RCA
Ricinus communis Agglutinin
- SDS-PAGE
sodium dodecyl sulphate-polyacrylamide gel electrophoresis
- TCA
trichloroacetic acid
- UA
Uterine Agglutinin
- WGA
Wheat-germ Agglutinin 相似文献
173.
Ranajit K. Banerjee 《Molecular and cellular biochemistry》1988,83(2):105-128
Summary It is well known that the partial reduction of oxygen can result in the formation of highly reactive oxygen products. Hydrogen peroxide is one of these metabolites of oxygen. Peroxidases utilize this metabolite for a variety of functions. It is the purpose of this treatise to review the nature and function of various membrane peroxidases in the body. 相似文献
174.
This study examines the effect of melengestrol acetate (MGA) implants on reproductive function and various biochemical parameters, ovarian activity, and uterine morphology in ten female common marmosets implanted for either 6-8 or 19-21 months. Measures of body weight, concentrations of urinary glucose and blood liver enzymes were taken. Ovarian activity was assessed by analysis of urinary progestin levels and ultrasound examinations of the ovaries. Ultrasonography was also used to evaluate uterine morphology. MGA was highly effective in preventing pregnancies in the study animals. No changes in biochemical parameters were found; however, seven females developed a substantial weight gain during the study. Follicular development was not suppressed, as indicated by the presence of antral follicles, luteinized structures, and elevated urinary progestin levels. The uteri of the MGA-treated subjects were moderately enlarged with a thickened endometrium that showed a marked change in structural appearance indicative of hypertrophy and decidualization. After implant removal these changes quickly disappeared and all females ovulated within 3 weeks and conceived within 4 months post-treatment. MGA appears to be an acceptable contraceptive in the marmoset, although non-steroidal methods should be evaluated as possible potential alternatives. 相似文献
175.
摘要 目的:研究三维能量多普勒超声联合血清人附睾蛋白4(HE4)、胸苷激酶1(TK1)、甲壳质酶蛋白40(YKL-40)对绝经后出血患者子宫内膜癌的预测价值。方法:选择我院2019年10月~2022年10月收治的150例绝经后出血患者。将其按照病理检查结果的差异分为子宫内膜癌组31例与子宫内膜良性增生组119例。对所有患者均开展三维能量多普勒超声检查,并检测血清HE4、TK1、YKL-40水平。以受试者工作特征曲线(ROC)分析三维能量多普勒超声联合血清HE4、TK1、YKL-40水平预测绝经后出血患者子宫内膜癌的效能。结果:子宫内膜癌组血流指数(FI)、血管形成指数(VI)、血管形成-血流指数(VFI)以及由该三参数构建的综合指数I相较于子宫内膜良性增生组均更高(均P<0.05)。子宫内膜癌组血清HE4、TK1、YKL-40水平相较于子宫内膜良性增生组均更高(均P<0.05)。经ROC曲线分析发现:三维能量多普勒超声联合血清HE4、TK1、YKL-40水平预测绝经后出血患者子宫内膜癌的曲线下面积(AUC)、灵敏度、特异度以及约登指数均高于上述四项单独预测。结论:三维能量多普勒超声联合血清HE4、TK1、YKL-40水平预测绝经后出血患者子宫内膜癌的效能较佳。 相似文献
176.
S. Lönnberg P. Nieminen L. Kotaniemi‐Talonen H. Kujari J. Melkko G. Granroth M. Vornanen T. Pietiläinen J. Arola J. Tarkkanen T. Luostarinen A. Anttila 《Cytopathology》2012,23(3):172-180
S. Lönnberg, P. Nieminen, L. Kotaniemi‐Talonen, H. Kujari, J. Melkko, G. Granroth, M. Vornanen, T. Pietiläinen, J. Arola, J. Tarkkanen, T. Luostarinen and A. Anttila Large performance variation does not affect outcome in the Finnish cervical cancer screening programme Objective: Cytology screening for prevention of cervical cancer can reduce incidence and mortality by more than 80% in settings with good organization and rigorous quality control. Audit studies are essential for reaching and maintaining a high quality of screening. The aim of this study was to evaluate variation in performance indicators by screening laboratory and assess the impact on the effectiveness of screening as indicated by cervical intraepithelial neoplasia grade 3 and above (CIN3+) rates after a negative screen. Methods: Seven cytology screening laboratories operating during 1990–1999 with a total of 953 610 screening tests performed were included in the study. By linking screening and cancer register files, all cases of CIN3+ diagnosed in the screened population were identified. For 395 CIN3+ cases with a preceding negative screen and 787 controls, a re‐evaluation of smears was undertaken to uncover false negative screening tests. Performance parameters and rates of CIN3+ after a negative screen were analysed for interlaboratory heterogeneity. Results: The rates of follow‐up recommendations and referrals varied by up to 3.6‐ (2.8–10.2%) and 4.0‐fold (0.03–0.12%), respectively. CIN1, CIN2 and CIN3+ screen detection rates differed by up to 8.5‐ (0.02–0.17%), 5.4‐ (0.05–0.25%) and 3.3‐fold (0.05–0.18%). False negative rates determined by re‐evaluation showed up to 2.1‐fold differences (29–62%). Rates of CIN3+ after a negative screen (0.023–0.048%) and as a proportion of total CIN3+ (15–31%) in the screened population were low and did not vary significantly. Conclusions: There were large variations in the sensitivity–specificity trade‐off between laboratories, reflected in all performance indicators as well as in the test validity estimates of the re‐evaluation phase, but not in screening effectiveness. Even though performance variations do not always have an impact on the effectiveness of screening, they lead to variations in cost, treatment and psychological burden, and should be addressed. 相似文献
177.
《Bioorganic & medicinal chemistry letters》2014,24(1):141-146
In this Letter we describe SAR investigation on the cyclopentyl-triazolol-pyrimidine scaffold in pursuit of new oral P2Y12 inhibitors. Different synthetic routes were developed for variations at the cyclopentyl core. Optimization finally led to compound 2d which was advanced into preclinical development based on better potency and safety profile in comparison to ticagrelor. 相似文献
178.
《Bioscience, biotechnology, and biochemistry》2013,77(4):1006-1008
Skipjack samples were prepared using two different killing methods, namely, struggling death in iced sea water (control) and instant death by mechanical bleeding. The hemoglobin content in the bled muscles was significantly lower than that in the control. 4-Hydroxyhexenal content in the bled muscles was significantly lower than that in the control over 2 d of storage at 0 °C. 相似文献
179.
Giulia Cavaliere 《Bioethics》2020,34(7):727-734
In a recent article in this journal, Kathryn MacKay advances a defence of ectogenesis that is grounded in this technology’s potential to end—or at least mitigate the effects of—gender-based oppression. MacKay raises important issues concerning the socialization of women as ‘mothers’, and the harms that this socialization causes. She also considers ectogenesis as an ethically preferable alternative to gestational surrogacy and uterine transplantation, one that is less harmful to women and less subject to being co-opted to further oppressive ends. In this article, I challenge some of the assumptions that underlie MacKay’s case in favour of ectogenesis by questioning whether the relationship between women’s capacity to gestate and birth children and gender-based oppression is as strong as MacKay makes it out to be. I subsequently argue that—even if MacKay’s reading of this relationship is accurate—ectogenesis is not a desirable means to end gender-based oppression. It embodies a strategy that could be used to pursue liberating projects that follow what Iris Marion Young defines as ‘the ideal of assimilation’, but that must be resisted. I then concur with MacKay’s contention that ectogenesis is better than gestational surrogacy and uterine transplantation. My argument is that many of the problematic issues that MacKay herself sees as features of these practices will not disappear with ectogenesis. Finally, I conclude that MacKay’s narrow focus on women’s biology and ectogenesis as a solution to gender-based oppression results in the overlooking of broader systemic issues that contribute to the upholding of oppressive norms. 相似文献
180.
吉林省47年育成的水稻品种根系伤流液重量变化及其与剑叶光合速率的关系 总被引:2,自引:0,他引:2
为了解不同年代水稻品种根系活力的变化及其与叶片光合的关系,以根系伤流液重量作为根系活力指标,研究了吉林省1958-2005年间育成的33个水稻品种抽穗后根系伤流液重量变化及其与剑叶净光合速率的关系。2--~-的研究结果表明,47年的遗传改良导致了水稻品种根系伤流液重量增加,根系伤流液重量与品种的育成年份呈显著正相关,与剑叶光合速率也呈显著正相关。抽穗后根系伤流液重量可以作为剑叶光合能力和高产的参考指标。 相似文献