Worldwide sequence conservation of transmission-blocking vaccine candidate Pvs230 in Plasmodium vivax

Pfs230, surface protein of gametocyte/gamete of the human malaria parasite, Plasmodium falciparum, is a prime candidate of malaria transmission-blocking vaccine. Plasmodium vivax has an ortholog of Pfs230 (Pvs230), however, there has been no study in any aspects on Pvs230 to date. To investigate whether Pvs230 can be a vivax malaria transmission-blocking vaccine, we performed evolutionary and population genetic analysis of the Pvs230 gene (pvs230: PVX_003905). Our analysis of Pvs230 and its orthologs in eight Plasmodium species revealed two distinctive parts: an interspecies variable part (IVP) containing species-specific oligopeptide repeats at the N-terminus and a 7.5 kb interspecies conserved part (ICP) containing 14 cysteine-rich domains. Pvs230 was closely related to its orthologs, Pks230 and Pcys230, in monkey malaria parasites. Analysis of 113 pvs230 sequences obtained from worldwide, showed that nucleotide diversity is remarkably low in the non-repeat 8-kb region of pvs230 (theta pi = 0.00118) with 77 polymorphic nucleotide sites, 40 of which results in amino acid replacements. A signature of purifying selection but not of balancing selection was seen on pvs230. Functional and/or structural constraints may limit the level of polymorphism in pvs230. The observed limited polymorphism in pvs230 should ground for utilization of Pvs230 as an effective transmission-blocking vaccine. (C) 2011 Elsevier Ltd. All rights reserved.

Stability of the curvature perturbation in dark sectors` mutual interacting models

We consider perturbations in a cosmological model with a small coupling between dark energy and dark matter. We prove that the stability of the curvature perturbation depends on the type of coupling between dark sectors. When the dark energy is of quintessence type, if the coupling is proportional to the dark matter energy density, it will drive the instability in the curvature perturbations: however if the coupling is proportional to the energy density of dark energy, there is room for the stability in the curvature perturbations. When the dark energy is of phantom type, the perturbations are always stable, no matter whether the coupling is proportional to the one or the other energy density. (C) 2008 Elsevier B.V. All rights reserved.

Sjuksköterskestudenters upplevelse av den kliniska färdighetsträningen på Kompetenscenter : Fokusgruppsintervjuer med sjuksköterskestuderande

Syfte: Syfte med denna studie var att belysa hur sjuksköterskestudenter upplevde den kliniska färdighetsträningen på Kompetenscenter. Metod: Den genomfördes som en empirisk studie med kvalitativ ansats där två fokusgruppsintervjuer med fem sjuksköterskestuderande i vardera utfördes. Deltagarna var mellan 22 och 30 år. Materialet analyserades med hjälp av kvalitativ innehållsanalys. Resultat: I analysen framkom ett tema, tre kategorier och tio subkategorier. Studenternas upplevelser speglade ett behov av att lärandemiljön, lärarna och undervisningen bör ha en verklighetsanknytning. Studenterna upplevde den fysiska miljön som autentiskt vilket var viktigt för dem. De framhöll även att läromaterialet bör vara verklighetstroget, vara av god kvalitet och finnas i tillräckligt antal. Studenterna uttryckte behov av trygghet och framhöll vikten av en god relation med läraren. De uttryckte även behov av samstämmiga lärare och poängterade behov att metoder och rutiner som lärs ut skulle vara enhetliga och baseras på aktuell evidens. För att läraren skulle uppfattas trovärdig framhöll de att vederbörande bör ha en verklighetsanknytning. De underströk vikten av att övningarna skulle upplevas verkliga och vara relevanta för det kommande yrket. Studenterna önskade interprofessionellt lärande då de trodde det kunde öka känslan av sammanhang och verklighet. Konklusion: Studenternas upplevelser av den kliniska färdighetsträningen på KC gav uttryck för en verklighetsförankrad lärandemiljö. Studenterna uttryckte behov av att övningarna skulle var evidensbaserade och upplevas verkliga då det ökade deras förmåga att tillägna sig kunskaper i den kliniska färdighetsträningen. 

Maternal health care professionals perspective on the provision and use of antenatal and delivery care : a qualitative descriptive study in rural Vietnam

Background. High quality maternal health care is an important tool to reduce maternal and neonatal mortality. Services offered should be evidence based and adapted to the local setting. This qualitative descriptive study explored the perspectives and experiences of midwives, assistant physicians and medical doctors on the content and quality of maternal health care in rural Vietnam. Method. The study was performed in a rural district in northern Vietnam. Four focus group discussions with health care professionals at primary health care level were conducted. The data was analysed using qualitative manifest and latent content analysis. Result. Two main themes emerged: "Contextual conditions for maternal health care" and "Balancing between possibilities and constraints". Contextual conditions influenced both pregnant women's use of maternal health care and health care professionals' performance. The study participants stated that women's uses of maternal health care were influenced by economical constraints and cultural norms that impeded their autonomy in relation to childbearing. Structural constraints within the health care system included inadequate financing of the primary health care, resulting in lack of human resources, professional re-training and adequate equipment. Conclusion. Contextual conditions strongly influenced the performance and interaction between pregnant women and health care professionals within antenatal care and delivery care in a rural district of Vietnam. Although Vietnam is performing comparatively well in terms of low maternal and child mortality figures, this study revealed midwives' and other health care professionals' perceived difficulties in their daily work. It seemed maternal health care was under-resourced in terms of staff, equipment and continuing education activities. The cultural setting in Vietnam constituting a strong patriarchal society and prevailing Confucian norms limits women's autonomy and reduce their possibility to make independent decisions about their own reproductive health. This issue should be further addressed by policy-makers. Strategies to reduce inequities in maternal health care for pregnant women are needed. The quality of client-provider interaction and management of pregnancy may be strengthened by education, human resources, re-training and provision of essential equipment.