Simulation-based development: shaping clinical procedures for extra-uterine life support technology.

BACKGROUND: Research into Artificial Placenta and Artificial Womb (APAW) technology for extremely premature infants (born < 28 weeks of gestation) is currently being conducted in animal studies and shows promising results. Because of the unprecedented nature of a potential treatment and the high-risk and low incidence of occurrence, translation to the human condition is a complex task. Consequently, the obstetric procedure, the act of transferring the infant from the pregnant woman to the APAW system, has not yet been established for human patients. The use of simulation-based user-centered development allows for a safe environment in which protocols and devices can be conceptualized and tested. Our aim is to use participatory design principles in a simulation context, to gain and integrate the user perspectives in the early design phase of a protocol for this novel procedure. METHODS: Simulation protocols and prototypes were developed using an iterative participatory design approach; usability testing, including general and task-specific feedback, was obtained from participants with clinical expertise from a range of disciplines. The procedure made use of fetal and maternal manikins and included animations and protocol task cards. RESULTS: Physical simulation with the active participation of clinicians led to the diffusion of tacit knowledge and an iteratively formed shared understanding of the requirements and values that needed to be implemented in the procedure. At each sequel, participant input was translated into simulation protocols and design adjustments. CONCLUSION: This work demonstrates that simulation-based participatory design can aid in shaping the future of clinical procedure and product development and rehearsing future implementation with healthcare professionals.

Accelerated growth of orbital schwannomas during pregnancy does not correlate with sex hormone- or growth factor receptor status.

Purpose: Until now, three cases of growth of an orbital schwannoma during pregnancy have been published. We aim to provide additional insight in the effect of pregnancy on orbital schwannomas. Methods: We present two additional cases of accelerated growth of orbital schwannomas during pregnancy and investigate receptor expression profiles for estrogen, progesterone, androgen, VEGF, EGF, FGF, PDGF-Rß and ki-67 in the two pregnant cases and six non-pregnant cases. Results: Case 1: A 26-year-old woman developed unilateral exophthalmos during pregnancy, with normal visual acuity and ocular motility. During a subsequent pregnancy, again the exophthalmos progressed. MRI showed a mass suggestive of schwannoma. After delivery, resection of the lesion was performed through an anterior approach. Pathology confirmed schwannoma. The expression profile was positive for estrogen- and FGF receptors and ki-67, but negative for progesterone-, androgen- and other growth factor receptors. Case 2: A 24-year-old woman presented with diplopia and unilateral pain during pregnancy. She had normal visual acuity, but a mild exophthalmos and elevation deficit. MRI revealed an extraconal mass suggestive of schwannoma. After delivery, resection was performed through an anterior approach. Pathology confirmed the diagnosis. The expression profile was positive for ki-67, but negative for sex hormone- and growth factor receptors. In the six non-pregnant cases the expression profiles varied, with only one subject showing a strong expression of estrogen-, progesterone- and androgen receptors. Conclusions: Orbital schwannomas can experience growth during pregnancy. The underlying mechanism remains unclear as hormone- and growth factor expression profiles show no correlation to the pregnant state.

Cenozoic evolution of the steppe-desert biome in Central Asia.

The origins and development of the arid and highly seasonal steppe-desert biome in Central Asia, the largest of its kind in the world, remain largely unconstrained by existing records. It is unclear how Cenozoic climatic, geological, and biological forces, acting at diverse spatial and temporal scales, shaped Central Asian ecosystems through time. Our synthesis shows that the Central Asian steppe-desert has existed since at least Eocene times but experienced no less than two regime shifts, one at the Eocene-Oligocene Transition and one in the mid-Miocene. These shifts separated three successive "stable states," each characterized by unique floral and faunal structures. Past responses to disturbance in the Asian steppe-desert imply that modern ecosystems are unlikely to recover their present structures and diversity if forced into a new regime. This is of concern for Asian steppes today, which are being modified for human use and lost to desertification at unprecedented rates.

Food Safety Issues Related to Uses of Insects for Feeds and Foods.

Edible insects are expected to become an important nutrient source for animals and humans in the Western world in the near future. However, before insects can be put on the market, the safety of their use for feed and food is warranted. This literature study was prepared to provide an overview of the actual knowledge of possible food safety hazards, including chemical, microbiological, and allergenic agents and prions, to human and animal health upon the use of insects for food and feed, and to highlight data gaps and suggest the way forward. From the data available, heavy metals of concern are cadmium in black soldier fly and arsenic in yellow mealworm larvae. Investigated mycotoxins do not seem to accumulate. Residues of pesticides, veterinary drugs, and hormones, as well as dioxins and PCBs, are sometimes found in insects. Contamination of insects with pathogens to human health is a consequence of a combination of the substrates used and the farming and processing steps applied. Insects harbor a wide variety of microorganisms, and some human pathogenic bacteria may be present. In addition, insects may harbor and transmit parasites. There is no evidence so far insects may harbor pathogenic viruses or prions, but they may act as vectors. Insects and insect-derived products may have allergenic potential. In this review, evidence on some safety aspects is displayed, and data gaps are identified. Recommendations are given for future research to fill the most relevant data gaps.

[A woman with acute bilateral vision loss]. / Een vrouw met acuut bilateraal visusverlies.

A 46-year-old woman presented to the emergency department with progressive bilateral loss of vision followed by headache. She had been taking topiramate 25 mg daily for eight days before presentation. In the end, she was diagnosed with topiramate-induced acute glaucoma for which she received appropriate treatment.

[Unwillingness or overconfidence. Orthodontics as a dental specialty]. / Onwil of overmoed. Orthodontie als tandheelkundig specialisme.

January 31st 1953, fifty years ago, orthodontics was the first dental specialty to be recognized in The Netherlands. This article describes the development to this. After the Second World War the dentist emancipated rapidly and dentistry became an academic profession in 1947. At that time the dentist was assumed to have knowledge of every field in dentistry and for orthodontics as a specialty there was no role to play. A few years later the Board of the Dutch Dental Association had to conclude--with some distaste--that a specialty in orthodontics was inevitable. As the chairman of the subcommittee for orthodontics the Groningen professor of orthodontics K.G. Bijlstra (1905-1985) had an important role in this process. November 16th, 1953 the first fifteen orthodontists were registered in The Netherlands.

FMRP is associated to the ribosomes via RNA.

The FMR1 transcript is alternatively spliced and generates different splice variants coding for FMR1 proteins (FMRP) with a predicted molecular mass of 70-80 kDa. FMRP is widely expressed and localized in the cytoplasm. To study a possible interaction with other cellular components, FMRP was isolated and characterized under non-denaturing conditions. Under physiological salt conditions FMRP appears to have a molecular mass of > 600 kDa, indicating a binding to other cellular components. This interaction is disrupted in the presence of high salt concentrations. The dissociation conditions to free FMRP from the complex are similar to the dissociation of FMRP from RNA as shown before. The binding of FMRP from the complex is also disrupted by RNAse treatment. That the association of FMRP to a high molecular weight complex possibly occurs via RNA, is further supported by the observation that the binding of FMRP, containing an lle304Asn substitution, to the high molecular weight complex is reduced. An equal reduced binding of mutated FMRP to RNA in vitro was observed before under the same conditions. The reduced binding of FMRP with the lle304Asn substitution further indicates that the interaction to the complex indeed occurs via FMRP and not via other RNA binding proteins. In a reconstitution experiment where the low molecular mass FMRP (70-80 kDa) is mixed with a reticulocyte lysate (enriched in ribosomes) it was shown that FMRP can associate to ribosomes and that this binding most likely occurs via RNA.

Characterization of FMR1 proteins isolated from different tissues.

FMR1 protein expression was studied in different tissues. In human, monkey and murine tissues, high molecular mass FMR1 proteins (67-80 kDa) are found, as shown in lymphoblastoid cells lines. The identity of these proteins was confirmed by their absence in tissues from patients with the fragile X syndrome and a FMR1 knock-out mouse. An Ile367Asn substitution in the FMR1 protein did not alter the translation, processing and localization of FMR1 proteins in lymphoblastoid cells from a patient carrying this mutation. All the high molecular mass FMR1 proteins isolated from normal lymphoblastoid cells and cells from the patient with the Ile367Asn substitution were able to bind RNA. However, the FMR1 proteins of the patient had reduced affinity for RNA binding at high salt concentrations. In some human, monkey and murine tissues low molecular mass FMR1 proteins (39-41 kDa) were found, which had the same N terminus as the 67-90 kDa isoforms, but differ in their C terminus and are therefore most likely the result of carboxy-terminal proteolytic cleavage. These low molecular mass FMR1 proteins did not bind RNA, in contrast with the high molecular mass FMR1 proteins. The significance of these low molecular mass proteins remains to be studied.

Cognitive impairment in patients with multiple sclerosis and mild physical disability.

Forty mildly disabled and clinically stable patients with multiple sclerosis (MS), representative of the corresponding population in Northern Holland, with disability Status Scale scores evenly distributed within the 1 to 4 range, were compared with 40 age-, sex-, and education-matched normal controls on a battery of neuropsychological tests. Apart from impairments in perceptual-motor functioning, generally mild deficiencies in intelligence and, specifically, in memory were displayed in the MS group. Attentional processes appeared uncompromised. Increasing fatigue during testing could not account for poor performance. The memory deficits could be attributed to poor initial learning, although there was also evidence suggesting that accelerated forgetting of what had been learned may appear with the progression of MS. Seven patients (17.5%), as compared with none of the controls, were classified by blind clinical judgement of test performance as definitely impaired.