"Finding oneself after critical illness": voices from the remission society.

The number of people who survive critical illness is increasing. In parallel, a growing body of literature reveals a broad range of side-effects following intensive care treatment. Today, more attention is needed to improve the quality of survival. Based on nine individual stories of illness experiences given by participants in two focus groups and one individual interview, this paper elaborates how former critically ill patients craft and recraft their personal stories throughout their illness trajectory. The analysis was conducted from a phenomenological perspective and led to the meaning structure; a quest to find oneself after critical illness. In this structure, illness represented a breakdown of the participants' lives, forcing them to develop a new understanding of themselves. Despite acute illness, they felt safe in hospital. Coming home, however, meant a constant balancing between health and illness, and being either in or out of control. To gain a deeper understanding of the participants' narratives of survival, the meaning structure was developed from a phenomenological life world perspective, Heidegger's concept of homelikeness and Arthur Frank's typologies of illness narratives. In conclusion listening to and acknowledging the patients' lived experiences of critical illness may support the patient efforts to establish the newly defined self and hence be vital for recovery. Phenomenology is one approach facilitating care tailored to the patients' lived experience of critical illness and its aftermaths.

Electrostrictive counterforce on fluid microdroplet in short laser pulse.

When a micrometer-sized fluid droplet is illuminated by a laser pulse, there is a fundamental distinction between two cases. If the pulse is short in comparison with the transit time for sound across the droplet, the disruptive optical Abraham-Minkowski radiation force is countered by electrostriction, and the net stress is compressive. In contrast, if the pulse is long on this scale, electrostriction is cancelled by elastic pressure and the surviving term of the electromagnetic force, the Abraham-Minkowski force, is disruptive and deforms the droplet. Ultrashort laser pulses are routinely used in modern experiments, and impressive progress has moreover been made on laser manipulation of liquid surfaces in recent times, making a theory for combining the two pertinent. We analyze the electrostrictive contribution analytically and numerically for a spherical droplet.

Vitamin E reduces endosulfan-induced toxic effects on morphology and behavior in early development of zebrafish (Danio rerio).

The aim of this study was to investigate if vitamin E (α-TOC) modulates the developmental toxicity of the pesticide endosulfan (ESF), using a modified zebrafish embryotoxicity test (ZET). Zebrafish (Danio rerio) embryos were exposed from 6 to 72 h post fertilization (hpf) to either ESF (0.1-50 mg/L) or α-TOC (0.01-3 mM) alone or in combination. The effects of these exposures on embryonic morphology, larval behavior and antioxidant gene expression were analyzed. Phenotypic analysis at 48 hpf showed that ESF led to a dose-dependent increase in embryonic deformities, including axis malformations, pericardial edema and reduced pigmentation. Co-exposure of ESF with α-TOC (1-3 mM) significantly (p < 0.05) reduced ESF-induced embryonic malformations. Exposure to solely α-TOC did not affect rates of survival or malformations. Behavior studies showed that ESF caused hyperactivity at 5 days post fertilization, indicating a developmental neurotoxic effect. The ESF-induced hyperactivity was ameliorated by α-TOC. Elevated ESF concentrations caused down-regulation of the antioxidant genes cuzn-sod, gpx1a and cat, suggesting that ESF promoted oxidative stress in the embryos. α-TOC did not prevent the ESF-induced dysregulation of these genes. These results demonstrate that α-TOC protects against phenotypic and behavioral effects caused by ESF but did not rescue ESF-induced aberrations in antioxidant gene expression.

Expression of two zebrafish homologues of the murine Six3 gene demarcates the initial eye primordia.

The murine homeobox gene Six3 and its Drosophila homologue sine oculis both have regulatory functions in eye development. We report the isolation and characterization of two zebrafish genes, six3 and six6, that are closely related to the murine Six3 gene. Zebrafish six3 may be the structural orthologue, while the six6 gene is more similar with respect to embryonic expression. Transcripts of both zebrafish six genes are first detected in involuting axial mesendoderm and, subsequently, in the overlying anterior neural plate from which the optic vesicles and the forebrain will develop. Direct correspondence between six3/six6 expression boundaries and the optic vesicles indicate essential roles in defining the eye primordia. During later stages only the six6 gene displays similar features of expression in the eyes and rostral brain as reported previously for murine Six3.

The zebrafish Pax3 and Pax7 homologues are highly conserved, encode multiple isoforms and show dynamic segment-like expression in the developing brain.

This study describes the isolation and characterization of zebrafish homologues of the mammalian Pax3 and Pax7 genes. The proteins encoded by both zebrafish genes are highly conserved (>83%) relative to the known mammalian sequences. Also the neural expression patterns during embryogenesis are very similar to the murine homologues. However, observed differences in neural crest and mesodermal expression relative to mammals could reflect some functional divergence in the development of these tissues. For the zebrafish Pax7 protein we report the first full-length amino acid sequences in vertebrates and show the existence of three additional isoforms which have truncations in the homeodomain and/or the C-terminal region. These novel variants provide evidence for additional isoform diversity of vertebrate Pax proteins.

Transient expression of a novel Six3-related zebrafish gene during gastrulation and eye formation.

Both the Drosophila homeobox gene sine oculis and its murine homologue Six3 have regulatory functions in eye development. In zebrafish, in addition to two previously reported homologues of murine Six3, we have identified a related gene (six7). Although the deduced Six7 protein shares less than 68% sequence identity with the other known zebrafish Six3-like proteins, the embryonic expression patterns have highly conserved features. The six7 transcripts are first detected in involuting axial mesendoderm and, subsequently, in the overlying neurectoderm from which the forebrain and optic primordia develop. Similar to the two other zebrafish Six3 homologues, the expression boundaries of six7 correspond quite closely with the edges of the optic vesicles. Hence, the partially overlapping expression domains of these three six genes probably contribute to anteroposterior specification and in defining the eye primordia.

Diverse PAH transcripts in lymphocytes of PKU patients with putative nonsense (G272X, Y356X) and missense (P281L, R408Q) mutations.

The majority of mutations in the human phenylalanine hydroxylase (PAH) gene that lead to the recessive disease phenylketonuria (PKU) are believed to affect the activity or stability of the PAH enzyme. In this study we have performed in vivo analyses of lymphocyte PAH mRNA from PKU patients homozygous for the PKU missense mutations P281L and R408Q as well as the nonsense mutations G272X and Y356X. The mutations G272X, P281L and R408Q, which are located outside the consensus splice site sequence, result in transcripts with one or more exons skipped in addition to full-length transcripts. The mutation Y356X results in transcripts with one or more exons skipped, but no full-length transcripts. Our findings question the value of functional and structural predictions of mutations at the protein level without analyses of the corresponding transcript.

RNA interference: mechanisms and applications.

RNA interference (RNAi) is a phenomenon induced by double-stranded RNA (dsRNA) in which gene expression is inhibited through specific degradation of mRNA. The mechanism involves conversion of dsRNA into short RNAs that direct ribonucleases to homologous mRNA targets. This process is related to normal defence against viruses and mobilisation of transposons. Treatment with dsRNA has become an important method for analysing gene functions in invertebrate organisms. RNAi has also been demonstrated in several vertebrate species but with lower efficiency. Development of procedures for in vivo production of dsRNA may provide efficient tools for tissue- and stage-specific gene targeting.

Selenium and mercury have a synergistic negative effect on fish reproduction.

Selenium (Se) can reduce the negative impacts of mercury (Hg) toxicity on growth and survival, but little is known about how these two elements interact in reproduction. In the following study we explored the effects of organic Hg and Se on the growth, survival and reproduction of female zebrafish (Danio rerio). Fish were fed one of four diets from 73 until 226 dpf in a 2 × 2 factorial design, using selenomethionine (SeMet) and methylmercury (MeHg) as the Se and Hg sources, respectively. Each diet contained Se at either requirement (0.7 mg Se/kg DM) or elevated levels (10 mg Se/kgDM), and Hg at either low (0.05 mg Hg/kg DM) or elevated (12 mg Hg/kg DM) levels. Between 151 and 206 dpf the female fish were pairwise crossed against untreated male fish and the mating success, fecundity, embryo survival, and subsequent overall reproductive success were measured. Elevated dietary Se reduced Hg levels in both the adult fish and their eggs. Elevated dietary Hg and Se increased egg Se levels to a greater extent than when dietary Se was elevated alone. At elevated maternal intake levels, egg concentrations of Se and Hg reflected the maternal dietary levels and not the body burdens of the adult fish. Elevated dietary Hg reduced the growth and survival of female fish, but these effects were largely prevented with elevated dietary Se. Elevated dietary Se alone did not affect fish growth or survival. Compared to other treatments, elevated dietary Hg alone increased both mating and overall reproductive success with <100 days of exposure, but decreased these parameters with >100 days exposure. Elevated dietary Se decreased fecundity, embryo survival, and overall reproductive success. The combination of elevated Se and Hg had a synergistic negative effect on all aspects of fish reproduction compared to those groups fed elevated levels of either Se or Hg. Overall the data demonstrate that while increased dietary Se may reduce adverse effects of Hg on the growth and survival in adult fish, it can negatively affect fish reproductive potential, and the effect on reproduction is enhanced in the presence of elevated Hg.

Selenium prevents downregulation of antioxidant selenoprotein genes by methylmercury.

Selenium (Se) is an essential nutrient required by Se-dependent proteins, termed selenoproteins. The selenoprotein family is small but diverse and includes key proteins in antioxidant, redox signaling, thyroid hormone metabolism, and protein folding pathways. Methylmercury (MeHg) is a toxic environmental contaminant that affects seafood safety. Selenium can reduce MeHg toxicity, but it is unclear how selenoproteins are affected in this interaction. In this study we explored how Se and MeHg interact to affect the mRNA expression of selenoprotein genes in whole zebrafish (Danio rerio) embryos. Embryos were obtained from adult zebrafish fed MeHg with or without elevated Se in a 2×2 factorial design. The embryo mRNA levels of 30 selenoprotein genes were then measured. These genes cover most of the selenoprotein families, including members of the glutathione peroxidase (GPX), thioredoxin reductase, iodothyronine deiodinase, and methionine sulfoxide reductase families, along with selenophosphate synthetase 2 and selenoproteins H, J-P, T, W, sep15, fep15, and fam213aa. GPX enzyme activity and larval locomotor activity were also measured. We found that around one-quarter of the selenoprotein genes were downregulated by elevated MeHg. These downregulated genes were dominated by selenoproteins from antioxidant pathways that are also susceptible to Se-deficiency-induced downregulation. MeHg also decreased GPX activity and induced larval hypoactivity. Elevated Se partially prevented MeHg-induced disruption of selenoprotein gene mRNA levels, GPX activity, and larval locomotor activity. Overall, the MeHg-induced downregulation and subsequent rescue by elevated Se levels of selenogenes regulated by Se status suggest that Se deficiency is a contributing factor to MeHg toxicity.

Double-stranded RNA induces specific developmental defects in zebrafish embryos.

Treatment with double-stranded RNA (dsRNA) has been shown to interfere with the function of specific genes in various invertebrate species. However, it has not yet been reported that this technique can be applied to vertebrates as well. We have investigated whether dsRNA treatment will inhibit gene function in zebrafish embryos. By microinjecting dsRNA corresponding to three genetically characterised genes we produced embryonic defects that were similar to the known mutant phenotypes of these loci. The efficiency of inducing specific defects (20-30%) was about 10-fold higher than in experiments with antisense RNA. We also observed that the level of the endogenous mRNA in zebrafish embryos was substantially reduced throughout the embryo following dsRNA injection. However, the interference of gene function showed a strong dependence on the amount of dsRNA. These findings suggest that dsRNA-mediated interference will become an important tool for analysing the functional roles of genes in zebrafish and other vertebrates.

Perinatal outcome after in vitro fertilisation.

A prospective series of 90 consecutive pregnancies (70 singleton, 16 twin and 4 triplet pregnancies) resulting in births of 114 infants after in vitro fertilisation (IVF) at Rigshospitalet were compared to a control group of pregnancies and deliveries in 70 non-IVF infertility patients with singleton pregnancies and 20 women with normal fertility with twin (n = 16) or triplet (n = 4) pregnancies. No differences in the incidence of third trimester pregnancy complications, abnormal fetal karyotypes or malformations were found. The number of women with spontaneous onset of labor and the gestational age at delivery were similar in the IVF and control groups. In singleton deliveries, the birth weight was lower (p < 0.025) in the IVF group (median 3145 g, range 890-4300 g) than in the control group (3399 g, 2592-4850 g), whereas in multiple gestation similar birth weights were found in the IVF and control groups. We conclude that the birth weight in singleton deliveries after IVF is lower than the birth weight in infertility patients treated differently. The cause of this difference remains obscure.

Subparsec-scale structure and evolution of Centaurus A (NGC5128).

We present a series of 8.4-GHz very-long-baseline radio interferometry images of the nucleus of Centaurus A (NGC5128) made with a Southern Hemisphere array, representing a 3.3-year monitoring effort. The nuclear radio jet is approximately 50 milliarcseconds in extent, or at the 3.5-megaparsec distance of NGC5128, approximately 1 parsec in length. Subluminal motion is seen and structural changes are observed on time scales shorter than 4 months. High-resolution observations at 4.8 and 8.4 GHz made in November 1992 reveal a complex morphology and allow us to unambiguously identify the self-absorbed core located at the southwestern end of the jet.