A Capabilities Approach to Prenatal Screening for Fetal Abnormalities

International guidelines recommend that prenatal screening for fetal abnormalities should only be offered within a non-directive framework aimed at enabling women in making meaningful reproductive choices. Whilst this position is widely endorsed, developments in cell-free fetal DNA based Non-Invasive Prenatal Testing are now raising questions about its continued suitability for guiding screening policy and practice. This issue is most apparent within debates on the scope of the screening offer. Implied by the aim of enabling meaningful reproductive choices is the idea that screening services should support women in accessing prenatal tests that best enable them to realize the types of reproductive choice that they find important. However, beyond whatever options meet the quality standards required for facilitating an informed decision, the remaining criteria of facilitating autonomous choice is strictly non-directive. As a result, policy makers receive little indication prior to consultation with each individual woman, about what conditions should be prioritized during the offer of screening. In this paper we try to address this issue by using the capabilities approach to further specify the non-directive aim of enabling meaningful reproductive choice. The resulting framework is then used to assess the relative importance of offering prenatal screening where concerning different types of genetic condition. We conclude that greater priority may be ascribed to offering prenatal screening for conditions that more significantly diminish a woman's central capabilities. It follows that serious congenital and earlier-onset conditions are more likely to fulfill these criteria.

Just choice: a Danielsian analysis of the aims and scope of prenatal screening for fetal abnormalities

Developments in Non-Invasive Prenatal Testing (NIPT) and cell-free fetal DNA analysis raise the possibility that antenatal services may soon be able to support couples in non-invasively testing for, and diagnosing, an unprecedented range of genetic disorders and traits coded within their unborn child's genome. Inevitably, this has prompted debate within the bioethics literature about what screening options should be offered to couples for the purpose of reproductive choice. In relation to this problem, the European Society of Human Genetics (ESHG) and American Society of Human Genetics (ASHG) tentatively recommend that any expansion of this type of screening, as facilitated by NIPT, should be limited to serious congenital and childhood disorders. In support of this recommendation, the ESHG and ASHG cite considerations of distribution justice. Notably, however, an account of justice in the organization and provision of this type of screening which might substantiate this recommendation has yet to be developed. This paper attempts to redress this oversight through an investigation of Norman Daniels' theory of Just health: meeting health needs fairly. In line with this aim, the paper examines what special moral importance (for Just health) screening for the purpose of reproductive choice might have where concerning serious congenital and childhood disorders in particular. The paper concludes that screening for reproductive choice where concerning serious congenital and childhood disorders may be important for providing women with fair opportunity to protect their health (by either having or not having an affected child).

Qualifying choice: ethical reflection on the scope of prenatal screening

In the near future developments in non-invasive prenatal testing (NIPT) may soon provide couples with the opportunity to test for and diagnose a much broader range of heritable and congenital conditions than has previously been possible. Inevitably, this has prompted much ethical debate on the possible implications of NIPT for providing couples with opportunities for reproductive choice by way of routine prenatal screening. In view of the possibility to test for a significantly broader range of genetic conditions with NIPT, the European Society of Human Genetics (ESHG) and American Society of Human Genetics (ASHG) recommend that, pending further debate, prenatal screening for reproductive choice should only be offered where concerning serious congenital conditions and childhood disorders. In support of this recommendation, the ESHG and ASHG discuss a number of ethical issues on which they prompt further debate: the informational privacy of the future child, the trivialization of abortion, the risk of information overload, and issues of distributive justice. This paper responds to this call with further reflection on each ethical issue and how it relates to the moral justification of providing couples with opportunities for meaningful reproductive choice. The paper concludes that whilst there may be good reasons for qualifying the scope of any unsolicited prenatal screening offer to serious congenital conditions and childhood disorders, if prenatal screening is justified for providing couples with opportunities for meaningful reproductive choice, then health services may have obligations to empower couples with the same opportunity where concerning other conditions.

Global health ethics: an introduction to prominent theories and relevant topics

Global health ethics is a relatively new term that is used to conceptualize the process of applying moral value to health issues that are typically characterized by a global level effect or require action coordinated at a global level. It is important to acknowledge that this account of global health ethics takes a predominantly geographic approach and may infer that the subject relates primarily to macro-level health phenomena. However, global health ethics could alternatively be thought of as another branch of health ethics. It may then relate to specific topics in themselves, which might also include micro-level health phenomena. In its broadest sense, global health ethics is a normative project that is best characterized by the challenge of developing common values and universal norms for responding to global health threats. Consequently, many subjects fall within its scope. Whilst several accounts of global health ethics have been conceptualized in the literature, a concise demarcation of the paradigm is still needed. Through means of a literature review, this paper presents a two-part introduction to global health ethics. First, the framework of 'borrowed' ethics that currently form the core of global health ethics is discussed in relation to two essential ethical considerations: 1) what is the moral significance of health and 2) what is the moral significance of boundaries? Second, a selection of exemplar ethical topics is presented to illustrate the range of topics within global health ethics.

Peritoneal macrophage and blood monocyte functions after open and laparoscopic-assisted cecectomy in rats

BACKGROUND

It has been well established that open abdominal surgery results in systemic immunosuppression postoperatively; in contrast, laparoscopic surgery is associated with significantly better preserved systemic immune function. However, when intraperitoneal (local) immune function is considered, laparoscopic procedures done under a CO2 pneumoperitoneum (pneumo) have been shown to result in greater immunosuppression compared to that of open surgery. Few studies have simultaneously assessed systemic and local immune function. The purpose of this study was to assess peripheral blood mononuclear cell (PBMC) and peritoneal macrophage tumor necrosis factor-alpha (TNF-alpha) levels, H2O2 production, and MHC class II antigen expression after open and laparoscopically assisted cecectomy in a rat model.

METHODS

A total of 75 Sprague Dawley rats were used for three separate experiments. For each study, rats were randomly divided into three groups: anesthesia alone (AC), laparoscopic-assisted cecectomy (LC), and open cecectomy via full laparotomy (OP). A CO2 pneumo was used for laparoscopic operations. On postoperative day 1 the animals were sacrificed, macrophages were harvested via intraperitoneal lavage, and PBMCs were isolated from whole blood obtained by cardiac puncture. In experiment 1, macrophages and PBMC from each animal were stimulated with lipopolysaccharide, after which TNF-alpha levels of the supernatant were determined. In experiment 2, after stimulation with PMA, H2O2 release was assessed by measuring fluorescence. In experiment 3, via flow cytometry, the number of cells with surface MHC class II proteins were determined. Data from the three groups in each experiment were compared using analysis of variance Tukey-Kramer tests.

RESULTS

Macrophages and PBMC from rats in the OP group released significantly more TNF-alpha than cells from rats in the LC ( p < 0.05) or AC ( p < 0.05) groups. Macrophages from rats in the OP group released significantly less H2O2 than cells from the AC ( p < 0.01) and LC ( p < 0.05) groups. There was no difference between the AC and LC results. No significant differences in PBMC H2O2 release were noted among any of the groups. OP group macrophages expressed significantly less MHC class II antigen than did AC group macrophages ( p < 0.05). No differences were noted among the LC results and either the OP or AC group's outcomes. No differences were noted in PBMC MHC class II expression among any of the groups.

CONCLUSIONS

In all instances, the LC group's macrophage results were similar to the AC group's results. OC group macrophages produced significantly more TNF-alpha and less H2O2 than both the AC and LC groups. MHC class II protein expression was less for the OC group than for the AC group. OC group PBMCs produced more TNF-alpha. No differences in PBMC H2O2 release or MHC class II expression were noted. Laparoscopic methods better preserves the baseline values of the parameters studied.

Neurosteroid hydroxylase CYP7B: vivid reporter activity in dentate gyrus of gene-targeted mice and abolition of a widespread pathway of steroid and oxysterol hydroxylation

The major adrenal steroid dehydroepiandrosterone (DHEA) enhances memory and immune function but has no known dedicated receptor; local metabolism may govern its activity. We described a cytochrome P450 expressed in brain and other tissues, CYP7B, that catalyzes the 7alpha-hydroxylation of oxysterols and 3beta-hydroxysteroids including DHEA. We report here that CYP7B mRNA and 7alpha-hydroxylation activity are widespread in rat tissues. However, steroids related to DHEA are reported to be modified at positions other than 7alpha, exemplified by prominent 6alpha-hydroxylation of 5alpha-androstane-3beta,17beta-diol (A/anediol) in some rodent tissues including brain. To determine whether CYP7B is responsible for these and other activities we disrupted the mouse Cyp7b gene by targeted insertion of an IRES-lacZ reporter cassette, placing reporter enzyme activity (beta-galactosidase) under Cyp7b promoter control. In heterozygous mouse brain, chromogenic detection of reporter activity was strikingly restricted to the dentate gyrus. Staining did not exactly reproduce the in situ hybridization expression pattern; post-transcriptional control is inferred. Lower level staining was detected in cerebellum, liver, and kidney, and which largely paralleled mRNA distribution. Liver and kidney expression was sexually dimorphic. Mice homozygous for the insertion are viable and superficially normal, but ex vivo metabolism of DHEA to 7alpha-hydroxy-DHEA was abolished in brain, spleen, thymus, heart, lung, prostate, uterus, and mammary gland; lower abundance metabolites were also eliminated. 7alpha-Hydroxylation of 25-hydroxycholesterol and related substrates was also abolished, as was presumed 6alpha-hydroxylation of A/anediol. These different enzyme activities therefore derive from the Cyp7b gene. CYP7B is thus a major extrahepatic steroid and oxysterol hydroxylase and provides the predominant route for local metabolism of DHEA and related molecules in brain and other tissues.

Protein kinase C-related kinase 2 phosphorylates the protein synthesis initiation factor eIF4E in starfish oocytes

Phosphorylation of eIF4E is required for protein synthesis during starfish oocyte maturation. The activity of protein kinase C-related kinase 2 (PRK2) increases prior to the phosphorylation of eIF4E (G. Stapleton et al., 1998, Dev. Biol. 193, 34-46). We investigate here whether eIF4E is activated by PRK2. A 3.5-kb eIF4E clone isolated from starfish cDNA is 57% identical to human eIF4E and contains the putative phosphorylation site serine-209. The serine-209 environment (SKTGS(209)MAKSRF) is similar to the consensus sequence of the phosphorylation site of protein kinase C and related kinases. A starfish eIF4E fusion protein (GST-4E) was phosphorylated in vitro by PRK2 in the presence of 1,2-diolyl-sn-glycerol 3-phosphate. In contrast, replacing the GST-4E serine-209 with an alanine significantly reduced this phosphorylation. Analysis by two-dimensional phosphopeptide mapping reveals a major phosphopeptide in trypsin-digested GST-4E, but not in its serine-209 mutant. Importantly, this major phosphopeptide in GST-4E corresponds to a major phosphopeptide of eIF4E isolated from (32)P-labeled oocytes. Thus, PRK2 may regulate translation initiation during oocyte maturation by phosphorylating the serine-209 residue of eIF4E in starfish. We also demonstrate that high levels of cAMP inhibit the activation of PRK2, eIF4E, and the eIF4E binding protein during starfish oocyte maturation, while PI3 kinase activates these proteins.

Regulation of a multigenic invasion programme by the transcription factor, AP-1: re-expression of a down-regulated gene, TSC-36, inhibits invasion

The transcription factor AP-1 (activator protein-1) is required for transformation by many oncogenes, which function upstream of it in the growth factor-ras signal transduction pathway. Previously, we proposed that one role of AP-1 in transformation is to regulate the expression of a multigenic invasion programme. As a test of this proposal we sought to identify AP-1 regulated genes based upon their differential expression in 208F rat fibroblasts transformed by FBR-v-fos (FBR), and to determine if they functioned in the invasion programme. Subtracted cDNA libraries specific for up- or down-regulated genes in FBRs compared to 208Fs were constructed and analysed. Northern analysis revealed that the cDNAs in both libraries represented differentially expressed genes. Nucleic acid sequence analysis of randomly selected cDNA clones from each library coupled with searches of nucleic acid and amino acid sequence databases determined that many of the cDNAs represented proteins that function in various aspects of the invasion process. Functional analysis of one the down-regulated genes, TSC-36/follistatin-related protein (TSC-36/Frp), which has not previously been associated with invasion, demonstrated that its expression in FBRs inhibited in vitro invasion. These results support the proposal that AP-1 in transformed cells regulates a multigenic invasion programme.

Transcriptional regulation of cell invasion: AP-1 regulation of a multigenic invasion programme

The focus of this review will be on the regulation of the multigenic invasion programme by activator protein-1 (AP-1). Investigation of AP-1-regulated gene expression in transformed cells can be used to identify the genes in the multigenic invasion programme and to validate them as targets for diagnosis or therapy.

Persistent central diabetes insipidus presenting in a very low birth weight infant successfully managed with intranasal dDAVP

We report a case of a premature very low birth weight infant who presented shortly after birth with idiopathic central diabetes insipidus that persisted beyond the neonatal period and has been successfully managed with intranasal 1-desamino-8-D-arginine vasopressin. Although this condition is rare in neonates, early recognition, evaluation, and therapy may prevent more severe morbidity. Long-term successful management resulting in normal growth and development during infancy can be achieved with intranasal 1-desamino-8-D-arginine vasopressin therapy.

Phosphorylation of protein kinase C-related kinase PRK2 during meiotic maturation of starfish oocytes

The resumption of meiosis in the developing starfish oocyte is the result of intracellular signaling events initiated by 1-methyladenine stimulation. One of the earliest detectable kinase activities during meiotic maturation of starfish oocytes is a protein kinase C or PKC-like activity. In this study, several isoforms of protein kinase C were cloned from the oocyte; however, the most abundant PKC-like maternal transcript corresponds to protein kinase C-related kinase 2 (PRK2). PRK2 is expressed in the immature oocyte and at least until germinal vesicle breakdown. Subcellular localization of PRK2 revealed a cytoplasmic distribution in the immature oocyte, which, during meiotic maturation, remained in the cytoplasm but also localized to the disintegrating germinal vesicle. Significantly, PRK2 is phosphorylated in vivo in response to 1-methyladenine which precedes MPF activation, making PRK2 a candidate regulator of early signaling events of meiotic maturation.

Cyp7b, a novel brain cytochrome P450, catalyzes the synthesis of neurosteroids 7alpha-hydroxy dehydroepiandrosterone and 7alpha-hydroxy pregnenolone

Steroids produced locally in brain (neurosteroids), including dehydroepiandrosterone (DHEA), influence cognition and behavior. We previously described a novel cytochrome P450, Cyp7b, strongly expressed in rat and mouse brain, particularly in hippocampus. Cyp7b is most similar to steroidogenic P450s and potentially could play a role in neurosteroid metabolism. To examine the catalytic activity of the enzyme mouse Cyp7b cDNA was introduced into a vaccinia virus vector. Extracts from cells infected with the recombinant showed NADPH-dependent conversion of DHEA (Km, 13.6 microM) and pregnenolone (Km, 4.0 microM) to slower migrating forms on thin layer chromatography. The expressed enzyme was less active against 25-hydroxycholesterol, 17beta-estradiol and 5alpha-androstane-3beta,17beta-diol, with low to undetectable activity against progesterone, corticosterone, and testosterone. On gas chromatography and mass spectrometry of the Cyp7b metabolite of DHEA the retention time and fragmentation patterns were identical to those obtained with authentic 7alpha-hydroxy DHEA. The reaction product also comigrated on thin layer chromatography with 7alpha-hydroxy DHEA but not with 7beta-hydroxy DHEA; when [7alpha-3H]pregnenolone was incubated with Cyp7b extracts the extent of release of radioactivity into the medium suggested that hydroxylation was preferentially at the 7alpha position. Brain extracts also efficiently liberated tritium from [7alpha-3H]pregnenolone and converted DHEA to a product with a chromatographic mobility indistinguishable from 7alpha-hydroxy DHEA. We conclude that Cyp7b is a 7alpha-hydroxylase participating in the synthesis, in brain, of neurosteroids 7alpha-hydroxy DHEA, and 7alpha-hydroxy pregnenolone.

A novel cytochrome P450 expressed primarily in brain

hct-1 (hippocampal transcript) was detected in a differential screen of a rat hippocampal cDNA library. Expression of hct-1 was enriched in the formation but was also detected in rat liver and kidney, though at much lower levels; expression was barely detectable in testis, ovary, and adrenal. In liver, unlike brain, expression was sexually dimorphic; hepatic expression was greatly reduced in female rats. In mouse, brain expression was widespread, with the highest levels being detected in corpus callosum; only low levels were detected in liver. Sequence analysis of rat and mouse hct-1 cDNAs revealed extensive homologies with cytochrome P450s (CYPs), a diverse family of heme-binding monooxygenases that metabolize a range of substrates including steroids, fatty acids, and xenobiotics. Among the CYPs, hct-1 is most similar (39% at the amino acid sequence) to cholesterol 7 alpha-hydroxylase (CYP7) and contains a postulated steroidogenic domain present in other steroid-metabolizing CYPs but clearly represents a type of CYP not previously reported. Genomic Southern analysis suggests that a single gene corresponding to hct-1 is present in mouse, rat, and human. hct-1 is unusual in that, unlike all other CYPs described, the primary site of expression is in the brain. Similarity to CYP7 and other steroid-metabolizing CYPs may argue that hct-1 (CYP7B) plays a role in steroid metabolism in brain, notable because of the documented ability of brain-derived steroids (neurosteroids) to modulate cognitive function in vivo.

Cell type-specific interactions of transcription factors with a housekeeping promoter in vivo

Mammalian housekeeping promoters represent a class of regulatory elements different from those of tissues-specific genes, lacking a TATA box and associated with CG-rich DNA. We have compared the organization of the housekeeping Htf9 promoter in different cell types by genomic footprinting. The sites of in vivo occupancy clearly reflected local combinations of tissue-specific and ubiquitous binding factors. The flexibility of the Htf9 promoter in acting as the target of cell-specific combinations of factors may ensure ubiquitous expression of the Htf9-associated genes.

Production of cytokines by mouse B cells: B lymphomas and normal B cells produce interleukin 10

We have examined a panel of murine Ly-1+ B lymphomas and purified normal murine peritoneal B cells separated into subsets on the basis of expression of the Ly-1 surface antigen, for their ability to produce cytokines. Where possible, we have used a combination of cytokine detection methods in order to compensate for differences in sensitivity and specificity, and the possibility of inhibitors masking an activity. All the lymphomas tested were shown to constitutively express TGF-beta and CSIF/IL-10. In addition, varying levels of IL-6, TNF-alpha and TNF-beta, and G-CSF, were demonstrable in most of the lymphomas, and variants of one lymphoma (CH12) additionally produced varying levels of IL-3, IL-4, and GM-CSF. FACS purified normal Ly-1+ and Ly-1- peritoneal B cells, were also shown to express RNA encoding CSIF/IL-10, IL-6, TNF-alpha and TNF-beta, and very low levels of G-CSF, following stimulation with LPS. These data were supported by the detection of IL-6 and CSIF/IL-10 in supernatants from LPS-stimulated Ly-1+ and Ly-1- B cells using specific immunoassays. None of the lymphomas or B cell preparations produced IL-1 alpha, IL-2, IL-5, IL-7, or IFN-gamma. The purity of our normal B cell populations was assessed by phenotypic analysis on the FACS and also by the disappearance of certain mRNA transcripts after purification, e.g. CD4, c-fms, GM-CSF, and IFN-gamma, most of which could be detected in LPS-stimulated total peritoneal cell populations. This suggested that our B cell purification method had reduced, to a level undetectable in our assays, contaminating T cells (CD4), macrophages (c-fms, GM-CSF), and NK cells (IFN-gamma). Absence of IL-3, IL-4, IL-5, and GM-CSF expression by LPS-stimulated Ly-1+ and Ly-1- B cells reduced the concern that contaminating peritoneal mast cells could account for the observed cytokine production. We therefore believe our data provide strong support for production of a subset of cytokines by LPS-stimulated normal B cells. Both the Ly-1+ B lymphomas and normal Ly-1+ and Ly-1- B cells appear capable of expressing IL-6, TNF-alpha, TNF-beta, and CSIF/IL-10.(ABSTRACT TRUNCATED AT 400 WORDS)