The Quality of Paediatric Nursing Care - Children’s Perspective

Hoitotyön laatu - lasten näkökulma Tämän kolmivaiheisen tutkimuksen tarkoituksena oli kuvailla lasten odotuksia ja arviointeja lasten hoitotyön laadusta sekä kehittää mittari kouluikäisille sairaalassa oleville lapsille laadun arviointiin. Perimmäisenä tavoitteena oli lasten hoitotyön laadun kehittäminen sairaalassa. Ensimmäisessä vaiheessa 20 alle kouluikäistä (4-6v) sekä 20 kouluikäistä (7-11v) lasta kuvailivat odotuksiaan lasten hoitotyön laadusta. Aineisto kerättiin haastattelulla ja lasten piirustusten avulla, sekä analysoitiin sisällön analyysilla. Lasten odotukset lasten hoitotyön laadusta kohdistuivat hoitajaan, hoitotyön toimintoihin ja ympäristöön, fyysinen ympäristö korostui piirustuksissa. Ensimmäisen vaiheen tulosten, aikaisemman kirjallisuuden sekä Leino-Kilven “HYVÄ HOITO” mittarin pohjalta kehitettiin “Lasten Hoidon Laatu Sairaalassa” (LHLS) mittari ja testattiin sen psykometrisiä ominaisuuksia tutkimuksen toisessa vaiheessa. Mittaria kehitettiin ja testattiin kolmen vaiheen kautta. Aluksi asiantuntijapaneeli (n=7) arvioi mittarin sisältöä. Seuraavaksi mittari esitestattiin kahdesti kouluikäisillä sairaalassa olevilla lapsilla (n=41 ja n=16), samassa vaiheessa myös viiden lastenosaston hoitajat (n=19) yhdessä arvioivat mittarin sisältöä sekä 8 lasta. Lopuksi mittaria testattiin kouluikäisillä lapsilla (n=388) sairaalassa sekä hoitajat (n=198) arvioivat mittarin sisällön validiteettia. Mittarin kehittämisen aikana päälaatuluokkien: hoitajan ominaisuudet, hoitotyön toiminnot ja hoitotyön ympäristö Cronbachin alfa kertoimet paranivat. Pääkomponentti analyysi tuki mittarin hoitotyön toimintojen ja ympäristön alaluokkien teoreettista rakennetta. Kolmannessa vaiheessa “Lasten Hoidon Laatu Sairaalassa” (LHLS III, versio neljä) mittarilla kerättiin aineisto Suomen yliopistosairaaloiden lastenosastoilta kouluikäisiltä 7-11 -vuotiailta lapsilta (n=388). Mittarin lopussa lapsia pyydettiin lisäksi kuvailemaan kivointa ja ikävintä kokemustaan sairaalahoidon aikana lauseen täydennystehtävänä. Aineisto analysoitiin tilastollisesti sekä sisällön analyysilla. Lapset arvioivat fyysisen hoitoympäristön, hoitajien inhimillisyyden ja luotettavuuden sekä huolenpidon ja vuorovaikutustoiminnot kiitettäviksi. Lapset arvioivat hoitajien viihdyttämistoiminnot kaikkein alhaisimmiksi. Lapsen ikä ja sairaalantulotapa olivat yhteydessä lasten saamaan tiedon määrään. Lasten kivoimmat kokemukset liittyivät ihmisiin ja heidän ominaisuuksiinsa, toimintoihin, ympäristöön sekä lopputuloksiin. Ikävimmät kokemukset liittyivät potilaana oloon, tuntemuksiin sairauden oireista sekä erossaoloon, hoitotyön fyysisiin toimintoihin sekä ympäristöön. Tutkimuksen tulokset osoittavat lasten olevan kykeneviä arvioimaan omaa hoitoaan ja heidän näkökulmansa tulisi nähdä osana koko laadun kehittämisprosessia parannettaessa laatua käytännössä todella lapsilähtöisemmällä lähestymistavalla. “Lasten Hoidon Laatu Sairaalassa” (LHLS) mittari on mahdollinen väline saada tietoa lasten arvioinneista lasten hoitotyön laadusta, mutta mittarin testaamista tulisi jatkaa tulevaisuudessa

Quality of Abdominal Surgical Nursing Care

The study evaluates the quality of abdominal surgical nursing care. The data were collected from patients (n=1208) having undergone abdominal surgical operations on their last day of hospitalization and nurses (n=218) working in the same wards. Three instruments originally created in Finland and adapted to the Lithuanian context were used: (1) Good Nursing Care Scale for patients and nurses (GNCS-P, GNCS-N), (2) Nurse Competence Scale (NCS), and (3) Nurse Empowerment Scale (NES). Patient and nurses’ perceptions of the quality of nursing care were evaluated. In addition, nurses’ perceptions of their competence and empowerment were evaluated. The patient and nurses' perceptions of the quality of abdominal surgical nursing care were positive, with more criticism in the nurses’ perceptions. Both patients and nurses gave the lowest evaluation to the quality in the progress of nursing care and the co-operation with significant others. The nurses gave the highest evaluation to the self-assessed level of their competence and the frequency of using competences in practice, with the highest assessment given to situation management and their role at work and the lowest to teaching-coaching and ensuring quality. The nurse perceptions of their empowerment were positive in the qualities and performance of an empowered nurse and empowerment promoting factors, with the highest evaluation in moral principles and sociability and the lowest evaluation in the future-orientedness and expertise. The empowerment-impeding factors were evaluated as negative. The perceptions of the quality of nursing care of both patients and nurses had significant correlations with patient and nurse satisfaction and nurse job independence. The nurse perceptions of their competence and empowerment correlated with their education, the type of the nurse license, completed courses of development of their knowledge and skills, nurse job independence, and nurse satisfaction. The nurse perceptions of the quality of nursing care had a positive correlation with their perceptions of competence and empowerment. Generally, the quality of nursing care was evaluated as high and had correlations with the patients' demographic and satisfaction factors and with the nurse demographic, work-related, and satisfaction factors. The study produced the knowledge that the quality in co-operation with significant others and the progress of nursing process, surgical nurse competence in teaching-coaching, and future-orientedness of surgical nurse empowerment need to be improved in order to develop the quality of abdominal surgical nursing care. The knowledge may be used to offer better services for abdominal surgical patients and increase their satisfaction with nursing care, as well as to increase nurses' satisfaction with work and independence at work. The study suggests implications for clinical practice and management, nursing education, and nursing research.

Factors affecting immunoglobulin concentration in colostrum of healthy Holstein cows immediately after delivery

This study analyzed the influence of the number of milkings, number of births, and udder quarter in immunoglobulin (Ig) concentration in the colostrum of healthy Holstein cows. It was collected two samples of colostrum by manual milking, getting the first jets to completion of bacteriological examination and immunoglobulin levels by radial immunodiffusion test in agar gel. Positive samples for bacteriological examination were excluded from this investigation. Medians of immunoglobulin's G, A and M in the colostrum collected before the first and second milking were respectively 9,200 and 6,400mg/dL (p=0.0029); 400 and 200mg/dL (p=0.0018); 800 and 400mg/dL (p=0.0001). Median immunoglobulin concentration in animals that calved once, twice or three times or in cows that calved 4 to 6 times were 6,400; 6,400; 3,200 and 11,200mg/dL IgG; 100, 200, 100 and 800mg/dL IgA ; and 400, 400, 100 and 800mg/dL IgM, respectively. Concentrations of IgG, IgA and IgM were greater in animals that calved more than 4 times (p<0.05). Medians of IgG, IgA and IgM in the right fore quarter (RF), right hind quarter (RH), left fore quarter (LF) and left hind quarter (LH) were, respectively, 7,800; 6,400; 7,800 and 6,400mg/dL; 200, 200, 200 and 200mg/dL; and 400, 400, 400 and 400mg/dL. Ig concentrations in the colostrum of Holstein cows were influenced by the number of milkings after delivery and number of lactations. These variations may be considered risk factors to passive immunity transfer to newborn calves, predisposing them to diseases and causing economic losses to dairy production.

Nurse Competence of Graduating Nursing Students

The competence of graduating nursing students is an important issue in health care as it is related to professional standards, patient safety and the quality of nursing care. Many changes in health care lead to increased demand with respect to nurses’ competence as well the number of nurses. The purpose of this empirical study was to i) describe the nurse competence areas of nursing students in Europe, ii) evaluate the nurse competence of graduating nursing students, iii) identify factors related to the nurse competence, and to iv) assess the congruence between graduating nursing students’ self-assessments and their mentors’ assessments of students’ nurse competence. The study was carried out in two phases: descriptive phase and evaluation phase. The descriptive phase focused on describing the nurse competence areas of nursing students in Europe with the help of a literature review (n=10 empirical studies and n=4 additional documents). Thematic analysis was used as the analysis method. In the evaluation phase, the nurse competence with particular focus on nursing skills of graduating nursing students (n=154) was assessed. In addition, factors related to the nurse competence were examined. Also, the congruence between graduating nursing students’ self-assessments and their mentors’ assessments of students’ nurse competence was evaluated by comparing graduating nursing students’ self-assessments with the assessments by their mentors (n=42) in the final clinical placement in four university hospitals. Descriptive statistics and inferential statistics were used to analyse the data. Based on the results, the nurse competence of nursing students in Europe consists of nine main competence areas: (1) professional/ethical values and practice, (2) nursing skills and interventions, (3) communication and interpersonal skills, (4) knowledge and cognitive ability, (5) assessment and improving quality in nursing, (6) professional development, (7) leadership, management and teamwork, (8) teaching and supervision, and (9) research utilization. Graduating nursing students self-assessed their nurse competence as good. However, when graduating nursing students’ nurse competence was assessed by their mentors, the results were poorer. Readiness for practice based on nurse education, pedagogical atmosphere on the ward, supervisory relationship between student and mentor and being in paid work in health care at the moment of the study were the most significant factors related to the nurse competence. Conclusions: Nurse competence can be evaluated with a scale based on self-assessment, but other evaluation methods could be used alongside to ensure that nurse competence can be completed and evaluated critically. Practical implications are presented for nurse education and nursing practice. In future, longitudinal research is needed in order to understand the development of nurse competence during nurse education and the transition process from a nursing student to a professional nurse.

Online problem-based learning : perceptions of nursing educators /

A qualitative study was conducted to detennine 5 nursing educators' perceptions about the online application of a problem-based learning strategy in undergraduate nursing education. The question asked in the study was: Can the essential elements of face-to-face problem-based learning be supported in an online format? The data for this study came from 2 individual tape-recorded interviews with each of the 5 participants over a 3-month period and from a researchjournaI. The educators felt that student-centered learning and critical thinking could be supported within an online format. However, they noted that challenges could exist in terms of developing tutor roles, fostering student self-direction, facilitating group process and connections, and incorporating a nursing philosophy of online learning. The importance of tailoring an online problem-based learning course to reflect educators' philosophies and values in nursing emerged as an important theme from the interview responses. Overall, the participants suggested that an ideal environment would blend both face-to-face and online elements and that fewer elements would be offered in the first 2 years of the nursing program. They described a hybrid model of problem-based learning in which the online component could be used to support face-to-face sessions.

What are the components of humanized childbirth in a highly specialized hospital? : an organizational case study

Many studies have focused on the concept of humanization of birth in normal pregnancy cases or at low obstetric risk, but no studies, at our knowledge, have so far specifically focused on the humanization of birth in both high-risk, and low risk pregnancies, in a highly specialized hospital setting. The present study thus aims to: 1) define the specific components of the humanized birth care model which bring satisfaction to women who seek obstetrical care in highly specialized hospitals; and 2) explore the organizational and cultural dimensions which act as barriers or facilitators for the implementation of humanized birth care practices in a highly specialized, university affiliated hospital in Quebec. A single case study design was chosen for this thesis. The data were collected through semi-structured interviews, field notes, participant observations, selfadministered questionnaire, relevant documents, and archives. The samples comprised: 11 professionals from different disciplines, 6 administrators from different hierarchical levels within the hospital, and 157 women who had given birth at the hospital during the study. The performed analysis covered both quantitative descriptive and qualitative deductive and inductive content analyses. The thesis comprises three articles. In the first article, we proposed a conceptual framework, based on Allaire and Firsirotu’s (1984) organizational culture theory. It attempts to examine childbirth patterns as an organizational cultural phenomenon. In our second article, we answered the following specific question: according to the managers and multidisciplinary professionals practicing in a highly specialized hospital as well as the women seeking perinatal care in this hospital setting, what is the definition of humanized care? Analysis of the data collected uncovered the following themes which explained the perceptions of what humanized birth was: personalized care, recognition of women’s rights, humanly care for women, family-centered care,women’s advocacy and companionship, compromise of security, comfort and humanity, and non-stereotyped pregnancies. Both high and low risk women felt more satisfied with the care they received if they were provided with informed choices, were given the right to participate in the decision-making process and were surrounded by competent care providers. These care providers who humanly cared for them were also able to provide relevant medical intervention. The professionals and administrators’ perceptions of humanized birth, on the other hand, mostly focused on personalized and family-centered care. In the third article of the thesis, we covered the dimensions of the internal and external components of an institution which can act as factors that facilitate or barriers that prevent, a specialized and university affiliated hospital in Quebec from adopting a humanized child birthing care. The findings revealed that both the external dimensions of a highly specialized hospital -including its history, society, and contingency-; and its internal dimensions -including culture, structure, and the individuals present in the hospital-, can all affect the humanization of birth care in such an institution, whether separately, simultaneously or in interaction. We thus hereby conclude that the humanization of birth care in a highly specialized hospital setting, should aim to meet all the physiological, as well as psychological aspects of birth care, including respect of the fears, beliefs, values, and needs of women and their families. Integration of competent and caring professionals and the use of obstetric technology to enhance the level of certainty and assurance in both high-risk and low risk women are both positive factors for the implementation of humanized care in a highly specialized hospital. Finally, the humanization of birth care approach in a highly specialized and university affiliated hospital setting demands a new healthcare policy. Such policy must offer a guarantee for women to have the place of birth, and the health care professional of their choice as well as those, which will enable women to make informed choices from the beginning of their pregnancy.

Measuring and evaluating quality of care in referral maternities in Mali and Senegal in the context of overlapping interventions

Dans cette thèse, nous décrivons les résultats d’un projet de recherche visant à mesurer et évaluer la qualité des soins obstétricaux des hôpitaux de référence au Mali et au Sénégal. Dans ces pays, la mortalité maternelle hospitalière est élevée et est liée en partie à la pratique médicale inadéquate. Cette recherche a été réalisée dans le cadre de l’étude QUARITE, un essai randomisé en grappe évaluant l’efficacité du programme GESTA International visant à réduire la mortalité maternelle hospitalière. GESTA a été mis en œuvre entre 2008 et 2010 et consistait en la formation des professionnels de santé et en la revue des cas de décès maternels. En parallèle de QUARITE, les programmes de prévention de la transmission du VIH de la mère à l’enfant (PTME) ont été mis à l’échelle à travers les pays. Ces derniers ayant également la capacité d’augmenter la qualité des soins obstétricaux, nous avons donc évalué les effets des deux programmes (GESTA et PTME) sur la qualité des soins. Dans un premier temps, à l’aide d’une recension des écrits nous avons évalué la capacité d’un audit clinique basé sur des critères à mesurer la qualité des soins obstétricaux. Cet audit vérifiait si l’offre des soins avait respecté les critères cliniques définissant la meilleure prise en charge selon l’évidence scientifique et l’avis des experts. Nous avons démontré que cet outil est largement utilisé dans les pays à faibles et moyens revenus, malgré le peu d’évidence sur sa validité (article 1). Dans un deuxième temps, nous avons développé un audit clinique basé sur des critères qui s’applique au contexte ouest-africain et qui a été approuvé par des experts-obstétriciens nationaux et internationaux. À partir des dossiers obstétricaux, les actes médicaux posés pendant le travail et l’accouchement ont été évalués à l‘aide de cet instrument. La qualité des soins a été estimée sous forme de pourcentage de critères atteints. Appliqué dans différents contextes et par différents auditeurs, nous avons démontré que notre instrument est fiable et valide (article 3). Néanmoins, l’expérience de l’audit nous a amenés à nous questionner sur le mauvais remplissage des dossiers médicaux et ses conséquences sur la qualité des soins (article 2). Dans un troisième temps, l’outil a été appliqué à large échelle pour évaluer les effets de l’intervention GESTA (article 4). Nous avons mené une révision de plus de 800 dossiers obstétricaux dans 32 hôpitaux de référence (16 bénéficiaires de l’intervention et 16 non-bénéficiaires). Grâce à cet audit clinique, nous avons démontré que le programme GESTA contribue à l’amélioration de la qualité des soins, spécifiquement l’examen clinique lors de l’admission et le suivi après l’accouchement. Dernièrement, nous avons utilisé cet instrument afin d’évaluer les effets des programmes de PTME sur la qualité des soins obstétricaux (article 5). Notre travail a documenté que seulement certaines composantes du programme de PTME améliorent la qualité des soins telles que la formation des professionnels et les services complémentaires en nutrition. En conclusion, cette recherche a identifié plusieurs pistes d’intervention pour améliorer la qualité des soins obstétricaux en Afrique de l’Ouest.

Le dispositif institutionnel et la relation thérapeutique en salle d'accouchement : entre le risque, le savoir hégémonique et les rapports de pouvoir.

Ce mémoire vise à établir la complexité de la relation thérapeutique entre l’infirmière et le couple en salle d’accouchement. Sachant que la relation thérapeutique est essentielle à la réussite du processus de soins, sa conceptualisation demeure primordiale pour une meilleure compréhension de son impact et pour mener à bien les soins. Cette recherche ethnographique a voulu documenter les relations des infirmières avec des couples en salle d’accouchement dans un hôpital de l’île de Montréal. Ce mémoire aborde un thème central de l’anthropologie : les relations humaines. La question clef de ce mémoire questionne les facteurs qui entravent et qui favorisent la relation thérapeutique entre l’infirmière et le couple en salle d’accouchement. Cette recherche démontre des lacunes théoriques qui technicisent la relation thérapeutique et indique que la notion du risque, les normes institutionnelles, l’hégémonie du savoir obstétrical et le pouvoir médical sont des facteurs qui semblent avoir une grande influence dans la relation thérapeutique.

Apatite-Polymer Composites for the Controlled Dual Delivery of BMP-2 and BMP-6 for Bone Tissue Engineering

The release of growth factors from tissue engineering scaffolds provides signals that influence the migration, differentiation, and proliferation of cells. The incorporation of a drug delivery platform that is capable of tunable release will give tissue engineers greater versatility in the direction of tissue regeneration. We have prepared a novel composite of two biomaterials with proven track records - apatite and poly(lactic-co-glycolic acid) (PLGA) – as a drug delivery platform with promising controlled release properties. These composites have been tested in the delivery of a model protein, bovine serum albumin (BSA), as well as therapeutic proteins, recombinant human bone morphogenetic protein-2 (rhBMP-2) and rhBMP-6. The controlled release strategy is based on the use of a polymer with acidic degradation products to control the dissolution of the basic apatitic component, resulting in protein release. Therefore, any parameter that affects either polymer degradation or apatite dissolution can be used to control protein release. We have modified the protein release profile systematically by varying the polymer molecular weight, polymer hydrophobicity, apatite loading, apatite particle size, and other material and processing parameters. Biologically active rhBMP-2 was released from these composite microparticles over 100 days, in contrast to conventional collagen sponge carriers, which were depleted in approximately 2 weeks. The released rhBMP-2 was able to induce elevated alkaline phosphatase and osteocalcin expression in pluripotent murine embryonic fibroblasts. To augment tissue engineering scaffolds with tunable and sustained protein release capabilities, these composite microparticles can be dispersed in the scaffolds in different combinations to obtain a superposition of the release profiles. We have loaded rhBMP-2 into composite microparticles with a fast release profile, and rhBMP-6 into slow-releasing composite microparticles. An equi-mixture of these two sets of composite particles was then injected into a collagen sponge, allowing for dual release of the proteins from the collagenous scaffold. The ability of these BMP-loaded scaffolds to induce osteoblastic differentiation in vitro and ectopic bone formation in a rat model is being investigated. We anticipate that these apatite-polymer composite microparticles can be extended to the delivery of other signalling molecules, and can be incorporated into other types of tissue engineering scaffolds.

Qualidade de vida do cuidador de enfermagem e sua relação com o cuidar; Quality of life of the nursing caregiver and its relationship with care

Objective:To identify aspects that affect the quality of life of nursing caregivers and their relationship with care in an Intensive Care Unit for Adults (A-ICU). Methods:This was a descriptive study with qualitative approach, taking as subjects 21 professionals who constitute the nursing staff of the A-ICU of a school hospital in Maringá-PR. Unstructured interview was used as a strategy to collect data, conducted between May and June 2009. Data analysis was based on the method of content analysis. The categories identified were: overlooking improvement in quality of life related to the resources in an A-ICU; the quality of life influencing the form of care; interpersonal relationships into the health team reflecting on the quality of life and care. Results:The analysis of caregivers’ speech and the results of the observation showed that there is correlation between the aspects they consider influential in their quality of life and the way of caring for patients in an A-ICU.Conclusion: The findings indicate that, among the influential aspects, the stressful factors overlap the enhancing ones. From this perspective, dealing with caregiver’s suffering might be the starting point for the improvement in quality of care in an A-ICU.

Dendrimers: a new class of nanoscopic containers and delivery devices

Dendrimers and hyperbranched polymers are a relatively new class of materials with unique molecular architectures and dimensions in comparison to traditional linear polymers. This review details recent notable advances in the application of these new polymers in terms of the development of new polymeric delivery systems. Although comparatively young, the developing field of hyperbranched drug delivery devices is a rapidly maturing area and the key discoveries in drug-conjugate systems amongst others are highlighted. As a consequence of their ideal hyperbranched architectures, the utilisation of host-guest chemistries in dendrimers has been included within the scope of this review. (C) 2003 Elsevier Ltd. All rights reserved.

The use and usefulness of financial assistance to UK SMEs

Existing literature has paid considerable attention to the effects of supporting programmes on the survival and performance of small and medium-sized enterprises (SMEs), but it lacks a deep understanding of the benefits of the use of such assistance and the factors influencing the evaluation of such services from the perspective of SMEs. We examine the factors affecting the propensity to use assistance when SMEs make financial decisions and the usefulness perceived by the users. We examine 2500 UK SMEs and find that the use of assistance and the usefulness of such services, as perceived by SMEs, are much related to: the characteristics of the entrepreneur, the nature of the business, and the financial products used by the business. These empirical results imply that support and advice on financial decision making, available for SMEs, are important for them to better manage and to access finance. Assistance and advice are also very valuable for SMEs and entrepreneurs to compensate for their lack of human capital and thus facilitate overcoming possible problems in managing their businesses.

Myostatin gene knockdown through lentiviral-mediated delivery of shRNA for in vitro production of transgenic bovine embryos

Myostatin is described as a negative regulator of the skeletal muscle growth. Genetic engineering, in order to produce animals with double the muscle mass and that can transmit the characteristic to future progeny, may be useful. In this context, the present study aimed to analyse the feasibility of lentiviral-mediated delivery of short hairpin RNA (shRNA) targeting of myostatin into in vitro produced transgenic bovine embryos. Lentiviral vectors were used to deliver a transgene that expressed green fluorescent protein (GFP) and an shRNA that targeted myostatin. Vector efficiency was verified through in vitro murine myoblast (C2C12) cell morphology after inductive differentiation and by means of real-time PCR. The lentiviral vector was microinjected into the perivitellinic space of in vitro matured oocytes. Non-microinjected oocytes were used as the control. After injection, oocytes were fertilized and cultured in vitro. Blastocysts were evaluated by epifluorescence microscopy. Results demonstrated that the vector was able to inhibit myostatin mRNA in C2C12 cells, as the transducted group had a less amount of myostatin mRNA after 72 h of differentiation (p < 0.05) and had less myotube formation than the non-transduced group (p < 0.05). There was no difference in cleavage and blastocyst rates between the microinjected and control groups. After hatching, 3.07% of the embryos exhibited GFP expression, indicating that they expressed shRNA targeting myostatin. In conclusion, we demonstrate that a lentiviral vector effectively performed shRNA myostatin gene knockdown and gene delivery into in vitro produced bovine embryos. Thus, this technique can be considered a novel option for the production of transgenic embryos and double muscle mass animals.

Functionalization of dendrimers for improved gene delivery to mesenchymal stem cell

Disease, injury, and age problems compromise human quality of life and continuously motivate the search for new and more efficacious therapeutic approaches. The field of Tissue Regeneration and Engineering has greatly evolved over the last years, mainly due to the combination of the important advances verified in Biomaterials Science and Engineering with those of Cell and Molecular Biology. In particular, a new and promising area arose – Nanomedicine – that takes advantage of the extremely small size and especial chemical and physical properties of Nanomaterials, offering powerful tools for health improvement. Research on Stem Cells, the self-renewing progenitors of body tissues, is also challenging to the medical and scientific communities, being expectable the appearance of new and exciting stem cell-based therapies in the next years. The control of cell behavior (namely, of cell proliferation and differentiation) is of key importance in devising strategies for Tissue Regeneration and Engineering. Cytokines, growth factors, transcription factors and other signaling molecules, most of them proteins, have been identified and found to regulate and support tissue development and regeneration. However, the application of these molecules in long-term regenerative processes requires their continuous presence at high concentrations as they usually present short half-lives at physiological conditions and may be rapidly cleared from the body. Alternatively, genes encoding such proteins can be introduced inside cells and be expressed using cell’s machinery, allowing an extended and more sustained production of the protein of interest (gene therapy). Genetic engineering of stem cells is particularly attractive because of their self-renewal capability and differentiation potential. For Tissue Regeneration and Engineering purposes, the patient’s own stem cells can be genetically engineered in vitro and, after, introduced in the body (with or without a scaffold) where they will not only modulate the behavior of native cells (stem cell-mediated gene therapy), but also directly participate in tissue repair. Cells can be genetically engineered using viral and non-viral systems. Viruses, as a result of millions of years of evolution, are very effective for the delivery of genes in several types of cells, including cells from primary sources. However, the risks associated with their use (like infection and immunogenic reactions) are driving the search for non-viral systems that will efficiently deliver genetic material into cells. Among them, chemical methods that are promising and being investigated use cationic molecules as carriers for DNA. In this case, gene delivery and gene expression level remain relatively low when primary cells are used. The main goal of this thesis was to develop and assess the in vitro potential of polyamidoamine (PAMAM) dendrimers based carriers to deliver genes to mesenchymal stem cells (MSCs). PAMAM dendrimers are monodispersive, hyperbranched and nanospherical molecules presenting unique characteristics that make them very attractive vehicles for both drug and gene delivery. Although they have been explored for gene delivery in a wide range of cell lines, the interaction and the usefulness of these molecules in the delivery of genes to MSCs remains a field to be explored. Adult MSCs were chosen for the studies due to their potential biomedical applications (they are considered multipotent cells) and because they present several advantages over embryonic stem cells, such as easy accessibility and the inexistence of ethical restrictions to their use. This thesis is divided in 5 interconnected chapters. Chapter I provides an overview of the current literature concerning the various non-viral systems investigated for gene delivery in MSCs. Attention is devoted to physical methods, as well as to chemical methods that make use of polymers (natural and synthetic), liposomes, and inorganic nanoparticles as gene delivery vectors. Also, it summarizes the current applications of genetically engineered mesenchymal stem cells using non-viral systems in regenerative medicine, with special focus on bone tissue regeneration. In Chapter II, the potential of native PAMAM dendrimers with amine termini to transfect MSCs is evaluated. The level of transfection achieved with the dendrimers is, in a first step, studied using a plasmid DNA (pDNA) encoding for the β-galactosidase reporter gene. The effect of dendrimer’s generation, cell passage number, and N:P ratio (where N= number of primary amines in the dendrimer; P= number of phosphate groups in the pDNA backbone) on the level of transfection is evaluated, being the values always very low. In a second step, a pDNA encoding for bone morphogenetic protein-2, a protein that is known for its role in MSCs proliferation and differentiation, is used. The BMP-2 content produced by transfected cells is evaluated by an ELISA assay and its effect on the osteogenic markers is analyzed through several classical assays including alkaline phosphatase activity (an early marker of osteogenesis), osteocalcin production, calcium deposition and mineralized nodules formation (late osteogenesis markers). Results show that a low transfection level is enough to induce in vitro osteogenic differentiation in MSCs. Next, from Chapter III to Chapter V, studies are shown where several strategies are adopted to change the interaction of PAMAM dendrimers with MSCs cell membrane and, as a consequence, to enhance the levels of gene delivery. In Chapter III, generations 5 and 6 of PAMAM dendrimers are surface functionalized with arginine-glycine-aspartic acid (RGD) containing peptides – experiments with dendrimers conjugated to 4, 8 and 16 RGD units were performed. The underlying concept is that by including the RGD integrin-binding motif in the design of the vectors and by forming RGD clusters, the level of transfection will increase as MSCs highly express integrins at their surface. Results show that cellular uptake of functionalized dendrimers and gene expression is enhanced in comparison with the native dendrimers. Furthermore, gene expression is dependent on both the electrostatic interaction established between the dendrimer moiety and the cell surface and the nanocluster RGD density. In Chapter IV, a new family of gene delivery vectors is synthesized consisting of a PAMAM dendrimer (generation 5) core randomly linked at the periphery to alkyl hydrophobic chains that vary in length and number. Herein, the idea is to take advantage of both the cationic nature of the dendrimer and the capacity of lipids to interact with biological membranes. These new vectors show a remarkable capacity for internalizing pDNA, being this effect positively correlated with the –CH2– content present in the hydrophobic corona. Gene expression is also greatly enhanced using the new vectors but, in this case, the higher efficiency is shown by the vectors containing the smallest hydrophobic chains. Finally, chapter V reports the synthesis, characterization and evaluation of novel gene delivery vectors based on PAMAM dendrimers (generation 5) conjugated to peptides with high affinity for MSCs membrane binding - for comparison, experiments are also done with a peptide with low affinity binding properties. These systems present low cytotoxicity and transfection efficiencies superior to those of native dendrimers and partially degraded dendrimers (Superfect®, a commercial product). Furthermore, with this biomimetic approach, the process of gene delivery is shown to be cell surface receptor-mediated. Overall, results show the potential of PAMAM dendrimers to be used, as such or modified, in Tissue Regeneration and Engineering. To our knowledge, this is the first time that PAMAM dendrimers are studied as gene delivery vehicles in this context and using, as target, a cell type with clinical relevancy. It is shown that the cationic nature of PAMAM dendrimers with amine termini can be synergistically combined with surface engineering approaches, which will ultimately result in suitable interactions with the cytoplasmic membrane and enhanced pDNA cellular entry and gene expression. Nevertheless, the quantity of pDNA detected inside cell nucleus is always very small when compared with the bigger amount reaching cytoplasm (accumulation of pDNA is evident in the perinuclear region), suggesting that the main barrier to transfection is the nuclear membrane. Future work can then be envisaged based on the versatility of these systems as biomedical molecular materials, such as the conjugation of PAMAM dendrimers to molecules able to bind nuclear membrane receptors and to promote nuclear translocation.

Applicability of non-pharmacological strategies for pain relief in parturient: integrative review

MORAES, Maísa Suares Teixeira; ROLIM, Lariane Thays Albuquerque; ENDERS, Bertha Cruz; FARIAS, Glaucea Maciel de; DAVIM, Rejane Marie Barbosa. Applicability of non-pharmacological strategies for pain relief in parturient: integrative review. Revista de Enfermagem UFPE on line, v.4, n.especial, p.131-136, May/June 2010. Disponivel em:< http://www.ufpe.br/revistaenfermagem/index.php/revista/>.