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191.
Recombinant human Protein C (rHPC), expressed in human kidney293 cells, has a higher anticoagulant activity than plasma HPC,while its in vivo circulatory half-life is essentially unalteredcompared to that of the natural protein. In seeking to elucidatethe molecular basis for the improved efficacy of the recombinantantithrombotic drug, we focused on the carbohydrate moiety ofrHPC. Protein C is a heavily post-translationally modified serineprotease with four N-glycosylation sites. Glycosyl compositionanalysis of rHPC revealed a 5-fold higher fucose content anda 2-fold lower sialic acid content compared to plasma HPC. Inaddition, we found that rHPC contains N-acetylgaiac-tosamine(2.6 mol GalNAc/mol rHPC) in its Asn-linked oligosaccharides,while plasma HPC is devoid of GalNAc. The Asn-linked oligosaccharidesof rHPC were released by N-glycanase and separated into 25 fractionsby high-pH anion-exchange chromatography. The most abundantoligosaccharides were structurally characterized by glycosylcomposition and linkage analysis, in conjunction with 1H-NMRspectroscopy at 600 MHz. The structure of the major neutraloligosaccharide in rHPC was determined to be: Two representatives of the sialylated oligosaccharides in rHPCare: and Thus, many of the Asn-linked oligosaccharides in rHPC were foundto terminate in GaINAcß(1  相似文献   
192.
A woman’s lack of or limited reproductive autonomy could lead to adverse health effects, feeling of being inferior, and above all being unable to adequately care for her children. Little is known about the reproductive autonomy of married Ikwerre women of Rivers State, Nigeria. This study demonstrates how Ikwerre women understand the terms autonomy and reproductive rights and what affects the exercise of these rights. An exploratory research design was employed for this study. A semi-structured interview schedule was used to conduct thirty-four in-depth interviews and six focus group discussions with purposively sampled educated, semi-educated, and uneducated Ikwerre women in monogamous or polygynous marriages. The collected data was analysed qualitatively with MAXQDA 11 using open and axial coding. The interviews and focus group responses reveal a low level of awareness of autonomy and reproductive rights amongst the Ikwerre women in Nigeria. While some educated women were aware of their reproductive rights, cultural practices were reported to limit the exercise of these rights. Participants reported that Ikwerre culture is a patriarchal one where married women are expected to submit and obey their husbands in all matters; and a good married woman according to Ikwerre standard is one who complies with this culture. Women’s refusal of sexual advances from their husbands is described as not being acceptable in this culture; and hence rape in marriage is not recognized in Ikwerre culture. Education and awareness creation on the importance of women’s reproductive autonomy could improve their reproductive rights and autonomy in marital settings. Overcoming the patriarchal aspects of Ikwerre culture—for example, the greater value placed on male children than female children and treating women as incompetent individuals—is necessary to promote gender equality as well as help improve women’s reproductive autonomy.  相似文献   
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Maturity-onset diabetes of the young, MODY, is an autosomal dominant disease with incomplete penetrance. In a family with multiple generations of diabetes and several early onset diabetic siblings, we found the previously reported P33T PDX1 damaging mutation. Interestingly, this substitution was also present in a healthy sibling. In contrast, a second very rare heterozygous damaging mutation in the necroptosis terminal effector, MLKL, was found exclusively in the diabetic family members. Aberrant cell death by necroptosis is a cause of inflammatory diseases and has been widely implicated in human pathologies, but has not yet been attributed functions in diabetes. Here, we report that the MLKL substitution observed in diabetic patients, G316D, results in diminished phosphorylation by its upstream activator, the RIPK3 kinase, and no capacity to reconstitute necroptosis in two distinct MLKL−/− human cell lines. This MLKL mutation may act as a modifier to the P33T PDX1 mutation, and points to a potential role of impairment of necroptosis in diabetes. Our findings highlight the importance of family studies in unraveling MODY’s incomplete penetrance, and provide further support for the involvement of dysregulated necroptosis in human disease.Subject terms: Necroptosis, Diabetes  相似文献   
195.
The effects of the chemical inducers, gamma-aminobutyric acid (GABA) and potassium chloride (KCl), on the larval settlement and metamorphosis of the donkey-ear abalone, Haliotis asinina, was investigated. H. asinina larvae (5–6 h post-hatch) were exposed to a range of GABA (0.125–2.00 μM) and KCl (1.00–12.00 mM) concentrations for 72 h. Results of the dose response experiments showed that settlement and metamorphosis vary according to the dose levels of the inducer compounds. Under controlled laboratory conditions, 0.45–0.50 μM and 6.0 mM seemed to be the optima for GABA and KCl, respectively, as these concentrations elicited the greatest number of postlarvae that metamorphosed, settled or survived. However, GABA generally promoted better attachment and metamorphic response as well as survival than KCl in H. asinina postlarvae.  相似文献   
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Adult male pigeons, some intact and some castrated in adulthood, were housed in individual cages kept in an isolated room with temperature and lighting controlled. Weekly measurements were made of ad lib. food intake and body weight for 4 mo after surgery. Castration was followed by a significant depression in body weight and by initially depressed but then progressively enhanced feeding. Food deprivation elicited an increase in food intake proportional to body weight loss, but castrates consumed less food at 100%, 90%, and 80% of ad lib. feeding weight than either intact birds or castrates treated daily with testosterone propionate (TP). Castrates gained weight and ate more than controls in response to daily treatments (im) with TP (6 mg/400 g) or 5a-dihydrotestosterone (DHT, 6 mg/400 g), while androstenedione (15 mg/400 g) and androsterone (15 mg/400 g) were ineffective. Administration of 100 mg DHT (sc) to castrates produced a significant enhancement of body weight without elevating the level of food intake. The biological potency of these diverse androgens on male courtship behavior was reciprocal to that for weight-promoting potency. The results suggest that the structural requirements of the androgen molecule for promoting body weight differ from those for stimulating sexual behavior.  相似文献   
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The Ebola epidemic in Western Africa has highlighted issues related to weak health systems, the politics of drug and vaccine development and the need for transparent and ethical criteria for use of scarce local and global resources during public health emergency. In this paper we explore two key themes. First, we argue that independent of any use of experimental drugs or vaccine interventions, simultaneous implementation of proven public health principles, community engagement and culturally sensitive communication are critical as these measures represent the most cost‐effective and fair utilization of available resources. Second, we attempt to clarify the ethical issues related to use of scarce experimental drugs or vaccines and explore in detail the most critical ethical question related to Ebola drug or vaccine distribution in the current outbreak: who among those infected or at risk should be prioritized to receive any new experimental drugs or vaccines? We conclude that healthcare workers should be prioritised for these experimental interventions, for a variety of reasons.  相似文献   
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