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1.
Ann Med ; 54(1): 1265-1276, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35510813

RESUMO

BACKGROUND: Lower socioeconomic status (SES) is associated with higher mortality rates and the likelihood of receiving less evidence-based treatment after stroke. In contrast, little is known about the impact of SES on recovery after discharge from inpatient rehabilitation. The aim of this study was to investigate the influence of SES on long-term recovery after stroke. PATIENTS AND METHODS: In a prospective, observational, multicentre study, inpatients were recruited towards the end of rehabilitation. The 12-month follow-up focussed on upper limb motor recovery, measured by the Fugl-Meyer score. A clinically relevant improvement of ≥5.25 points was considered recovery. Patient-centric measures such as the Patient-reported Outcomes Measurement Information System-Physical Health (PROMIS-10 PH) provided secondary outcomes. Information on schooling, vocational training, income and occupational status pre-stroke entered a multidimensional SES index. Multivariate logistic regression models calculating odds ratios (ORs) and corresponding confidence intervals (CIs) were applied. SES was added to an initial model including age, sex and baseline neurological deficit. Additional exploratory analyses examined the association between SES and outpatient treatment. RESULTS: One hundred and seventy-six patients were enrolled of whom 98 had SES and long-term recovery data. Model comparisons showed the SES-model superior to the initial model (Akaike information criterion (AIC): 123 vs. 120, Pseudo R2: 0.09 vs. 0.13). The likelihood of motor recovery (OR = 17.12, 95%CI = 1.31; 224.18) and PROMIS-10 PH improvement (OR = 20.76, 95%CI = 1.28; 337.11) were significantly increased with higher SES, along with more frequent use of outpatient therapy (p = .02). CONCLUSIONS: Higher pre-stroke SES is associated with better long-term recovery after discharge from rehabilitation. Understanding these factors can improve outpatient long-term stroke care and lead to better recovery.KEY MESSAGEHigher pre-stroke socioeconomic status (SES) is associated with better long-term recovery after discharge from rehabilitation both in terms of motor function and self-reported health status.Higher SES is associated with significantly higher utilization of outpatient therapies.Discharge management of rehabilitation clinics should identify and address socioeconomic factors in order to detect individual needs and to improve outpatient recovery. Article registration: clinicaltrials.gov NCT04119479.


Assuntos
Reabilitação Neurológica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Pacientes Internados , Estudos Prospectivos , Recuperação de Função Fisiológica , Classe Social , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Extremidade Superior
3.
Sci Rep ; 8(1): 4820, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29556088

RESUMO

How organisms adapt to unfavorable environmental conditions by means of plasticity or selection of favorable genetic variants is a central issue in evolutionary biology. In the Maipo River basin, the fish Basilichthys microlepidotus inhabits polluted and non-polluted areas. Previous studies have suggested that directional selection drives genomic divergence between these areas in 4% of Amplified Fragment Length Polymorphism (AFLP) loci, but the underlying genes and functions remain unknown. We hypothesized that B. microlepidotus in this basin has plastic and/or genetic responses to these conditions. Using RNA-Seq, we identified differentially expressed genes in individuals from two polluted sites compared with fish inhabiting non-polluted sites. In one polluted site, the main upregulated genes were related to cellular proliferation as well as suppression and progression of tumors, while biological processes and molecular functions involved in apoptotic processes were overrepresented in the upregulated genes of the second polluted site. The ornithine decarboxylase gene (related to tumor promotion and progression), which was overexpressed in both polluted sites, was sequenced, and a parallel pattern of a heterozygote deficiency and increase of the same homozygote genotype in both polluted sites compared with fish inhabiting the non-polluted sites was detected. These results suggest the occurrence of both a plastic response in gene expression and an interplay between phenotypic change and genotypic selection in the face of anthropogenic pollution.


Assuntos
Proteínas de Peixes/genética , Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Marcadores Genéticos , Ornitina Descarboxilase/genética , Seleção Genética , Poluentes Químicos da Água/toxicidade , Animais , Evolução Biológica , Poluição Ambiental/efeitos adversos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo Genético
4.
Heredity (Edinb) ; 119(6): 429-437, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28953268

RESUMO

The utilization of similar habitats by different species provides an ideal opportunity to identify genes underlying adaptation and acclimatization. Here, we analysed the gene expression of two closely related salamander species: Salamandra salamandra in Central Europe and Salamandra infraimmaculata in the Near East. These species inhabit similar habitat types: 'temporary ponds' and 'permanent streams' during larval development. We developed two species-specific gene expression microarrays, each targeting over 12 000 transcripts, including an overlapping subset of 8331 orthologues. Gene expression was examined for systematic differences between temporary ponds and permanent streams in larvae from both salamander species to establish gene sets and functions associated with these two habitat types. Only 20 orthologues were associated with a habitat in both species, but these orthologues did not show parallel expression patterns across species more than expected by chance. Functional annotation of a set of 106 genes with the highest effect size for a habitat suggested four putative gene function categories associated with a habitat in both species: cell proliferation, neural development, oxygen responses and muscle capacity. Among these high effect size genes was a single orthologue (14-3-3 protein zeta/YWHAZ) that was downregulated in temporary ponds in both species. The emergence of four gene function categories combined with a lack of parallel expression of orthologues (except 14-3-3 protein zeta) suggests that parallel habitat adaptation or acclimatization by larvae from S. salamandra and S. infraimmaculata to temporary ponds and permanent streams is mainly realized by different genes with a converging functionality.


Assuntos
Aclimatação/genética , Ecossistema , Salamandra/genética , Adaptação Fisiológica/genética , Animais , Europa (Continente) , Expressão Gênica , Larva , Análise de Sequência com Séries de Oligonucleotídeos , Lagoas , Rios , Especificidade da Espécie , Transcriptoma
5.
Artigo em Alemão | MEDLINE | ID: mdl-26763526

RESUMO

A male, 12-year-old Cairn terrier suffering from Cushing's syndrome with two therapy-resistant inflammatory subcutaneous lesions was examined pathomorphologically and parasitologically. Within the subcutaneous tissue, there was a suppurative to necrotizing and histiocytic inflammation present with the formation of caverns. Intralesional whitish-grey cysts with a diameter of 1-4 mm were detected. Molecular investigations of the cysts confirmed the preliminary morphological identification as Cysticercus longicollis. The adenohypophysis showed an infiltrative growing carcinoma. Cysticercus longicollis is the metacestode of Taenia (T.) crassiceps, a tapeworm of foxes and coyotes. Small rodents are typical intermediate hosts, in which the metacestode develops within the body cavities as well as in the subcutis. Subcutaneous cysticercosis after infection with eggs of T. crassiceps is also described in different domestic animal species and in humans, who represent aberrant intermediate hosts. Immunosuppression due to Cushing's syndrome, probably caused by the tumor of the adenohypophysis, may have played a role in the pathogenesis of the present case.


Assuntos
Síndrome de Cushing/veterinária , Cisticercose/veterinária , Doenças do Cão/patologia , Doenças do Cão/parasitologia , Animais , Síndrome de Cushing/parasitologia , Cisticercose/complicações , Cisticercose/diagnóstico , Cães , Masculino
6.
J Neural Transm (Vienna) ; 122(11): 1573-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26179478

RESUMO

Continuous intrathecal Baclofen application (ITB) through an intracorporeal pump system is widely used in adults and children with spasticity of spinal and supraspinal origin. Currently, about 1200 new ITB pump systems are implanted in Germany each year. ITB is based on an interdisciplinary approach with neurologists, rehabilitation specialists, paediatricians and neurosurgeons. We are presenting the proceedings of a consensus meeting organised by IAB-Interdisciplinary Working Group for Movement Disorders. The ITB pump system consists of the implantable pump with its drug reservoir, the refill port, an additional side port and a flexible catheter. Non-programmable pumps drive the Baclofen flow by the reservoir pressure. Programmable pumps additionally contain a radiofrequency control unit, an electrical pump and a battery. They have major advantages during the dose-finding phase. ITB doses vary widely between 10 and 2000 µg/day. For spinal spasticity, they are typically in the order of 100-300 µg/day. Hereditary spastic paraplegia seems to require particularly low doses, while dystonia and brain injury require particularly high ones. Best effects are documented for tonic paraspasticity of spinal origin and the least effects for phasic muscle hyperactivity disorders of supraspinal origin. Oral antispastics are mainly effective in mild spasticity. Botulinum toxin is most effective in focal spasticity. Myotomies and denervation operations are restricted to selected cases of focal spasticity. Due to its wide-spread distribution within the cerebrospinal fluid, ITB can tackle wide-spread and severe spasticity.


Assuntos
Baclofeno/administração & dosagem , Transtornos dos Movimentos/tratamento farmacológico , Relaxantes Musculares Centrais/administração & dosagem , Espasticidade Muscular/tratamento farmacológico , Alemanha , Humanos , Bombas de Infusão Implantáveis/efeitos adversos , Injeções Espinhais
7.
Heredity (Edinb) ; 111(6): 520-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981957

RESUMO

Cottus rhenanus and Cottus perifretum have formed hybrid lineages and narrow hybrid zones that can be best explained through the action of natural selection. However, the underlying selective forces as well as their genomic targets are not well understood. This study identifies genomic regions in the parental species that cause hybrid incompatibilities and tests whether these manifest in a sex-specific manner to learn about processes that affect natural hybridization in Cottus. Interspecific F2 crosses were analyzed for 255 markers for genetic mapping and to detect transmission distortion as a sign for genetic incompatibilities. The Cottus map consists of 24 linkage groups with a total length of 1575.4 cM. A male heterogametic (XY) sex determination region was found on different linkage groups in the two parental species. Genetic incompatibilities were incomplete, varied among individuals and populations and were not associated with the heterogametic sex. The variance between populations and individuals makes it unlikely that there are species-specific incompatibility loci that could affect the gene pool of natural hybrids in a simple and predictable way. Conserved synteny with sequenced fish genomes permits to genetically study the Cottus genome through the transfer of genomic information from the model fish species. Homology relationships of candidate genomic regions in Cottus indicate that sex determination is not based on the same genomic regions found in other fish species. This suggests a fast evolutionary turnover of the genetic basis of sex determination that, together with the small size of the heterogametic regions, may contribute to the absence of fitness effects related to the Haldane's rule.


Assuntos
Hibridização Genética , Perciformes/genética , Processos de Determinação Sexual , Animais , Evolução Biológica , Mapeamento Cromossômico , Cruzamentos Genéticos , Feminino , Ligação Genética , Genômica , Masculino , Perciformes/fisiologia
8.
J Evol Biol ; 26(2): 229-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23323997

RESUMO

Hybridization has many and varied impacts on the process of speciation. Hybridization may slow or reverse differentiation by allowing gene flow and recombination. It may accelerate speciation via adaptive introgression or cause near-instantaneous speciation by allopolyploidization. It may have multiple effects at different stages and in different spatial contexts within a single speciation event. We offer a perspective on the context and evolutionary significance of hybridization during speciation, highlighting issues of current interest and debate. In secondary contact zones, it is uncertain if barriers to gene flow will be strengthened or broken down due to recombination and gene flow. Theory and empirical evidence suggest the latter is more likely, except within and around strongly selected genomic regions. Hybridization may contribute to speciation through the formation of new hybrid taxa, whereas introgression of a few loci may promote adaptive divergence and so facilitate speciation. Gene regulatory networks, epigenetic effects and the evolution of selfish genetic material in the genome suggest that the Dobzhansky-Muller model of hybrid incompatibilities requires a broader interpretation. Finally, although the incidence of reinforcement remains uncertain, this and other interactions in areas of sympatry may have knock-on effects on speciation both within and outside regions of hybridization.


Assuntos
Especiação Genética , Hibridização Genética , Adaptação Fisiológica , Animais , Fluxo Gênico , Fenótipo
9.
Acta Biomater ; 9(5): 6741-52, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23333865

RESUMO

One procedure to treat stenotic coronary arteries is the percutaneous transluminal coronary angioplasty (PTCA). In recent years, drug-eluting stents (DESs) have demonstrated elaborate ways to improve outcomes of intravascular interventions. To enhance DESs, the idea has evolved to design stents that elute specific small interfering RNA (siRNA) for better vascular wall regeneration. Layer-by-layer (LbL) technology offers the possibility of incorporating siRNA nanoplexes (NPs) to achieve bioactive medical implant coatings. The LbL technique was used to achieve hyaluronic acid/chitosan (HA/Chi) films with incorporated Chi-siRNA NPs. The multilayer growth was monitored by quartz crystal microbalance. The coating on the stents and its thickness were analyzed using fluorescence and scanning electron microscopy. All stents showed a homogeneous coating, and the polyelectrolyte multilayers (PEMs) were not disrupted after ethylene oxide sterilization or expansion. The in vitro uptake of fluorescent-labeled NPs from PEMs in primary human endothelial cells (ECs) was analyzed by flow cytometry for 2, 6 and 9 days. Furthermore, stents coated with HA/Chi and Chi-siRNA NPs were expanded into porcine arteries and showed ex vivo delivery of NPs. The films showed no critical results in terms of hemocompatibility. This study demonstrates that Chi-siRNA NPs can be incorporated into PEMs consisting of HA and Chi. We conclude that the NPs were delivered to ECs under in vitro conditions. Furthermore, under ex vivo conditions, NPs were transferred into porcine artery walls. Due to their good hemocompatibility, they might make an innovative tool for achieving bioactive coatings for coronary stents.


Assuntos
Materiais Biocompatíveis , Vasos Coronários , RNA Interferente Pequeno/administração & dosagem , Stents , Endotélio Vascular/citologia , Citometria de Fluxo , Humanos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência
10.
Thorac Cardiovasc Surg ; 59(6): 322-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21692023

RESUMO

BACKGROUND: Acute rejection reactions and the development of graft arterial disease are serious limitations after transplantation. Both are connected to the expression of adhesion molecules on the activated microvascular endothelium of the allograft. METHODS: siRNA-mediated silencing of ESELE, ICAM-1, and VCAM-1 on human cardiac microvascular cells (HCMEC) was investigated in order to inhibit leukocyte-endothelial interactions. HCMEC were investigated for the time-dependent expression of ESELE, ICAM-1, and VCAM-1 after TNF-α stimulation and for siRNA mediated suppression using a nonviral transfecting approach. Furthermore, the effects of siRNA transfection on leukocyte binding to the endothelium were analyzed. RESULTS: Transfection with siRNA induced a significant suppression of adhesion molecule expression, regardless of whether there had been a prior single or cocktail transfection of the sequences ( P < 0.05). The quantity of attaching leukocytes was significantly reduced after an equal silencing of adhesion molecules ( P < 0.05). CONCLUSIONS: This investigation demonstrates that liposomal transfection of HCMEC with specific siRNA sequences is capable of both repressing adhesion molecule expression and of reducing subsequent leukocyte-endothelial actions.


Assuntos
Moléculas de Adesão Celular/genética , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Microvasos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transfecção , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Técnicas de Cocultura , Vasos Coronários/citologia , Selectina E/genética , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular/genética , Lipossomos , Microvasos/citologia , Neutrófilos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética
11.
J Cardiovasc Surg (Torino) ; 52(2): 251-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21460776

RESUMO

AIM: Coronary artery bypass grafting (CABG) is a standard procedure for treatment of coronary heart disease. Eighty percent of all CABGs are performed with venous grafts which then get exposed to an arterial pressure after surgery. This widely used procedure, however, is complicated by the development of alterations in the vein graft wall, leading to a decreased patency rate and graft failure. This study enlightens the influence of an even moderate arterial pressure on the gene expression of adhesion molecules in venous grafts which play a decisive role for the early induction of atherogenesis. METHODS: Segments of porcine vena jugularis and arteria carotis were mounted in a simulated bypass circuit and subjected to pulsatile flow. Vessel segments were examined for adhesion molecule expression with quantitative real-time - polymerase chain reaction (qRT-PCR) and adherence of leukocytes was observed by confocal laser scanning microscopy and scanning electron microscopy. RESULTS: Veins grafts subjected to an even moderate arterial pressure showed a 14-fold increase of ICAM-1 expression already after 4 hours. An arterial pressure of around 100/80 mmHg was enough to stimulate the adhesion molecule expression Furthermore it led to a 9-fold increase of leukocyte adhesion to the venous endothelium, but, in contrast this was not the case in arteries. CONCLUSION: This study showed, that already 100 mmHg upregulates the expression of several adhesion molecules in pig veins followed by increased adhesion of leukocytes. Therefore, our data demonstrate the advantage of arteries for CABG, and that new therapeutic strategies are urgently necessary to protect vein grafts either physically or pharmacologically if arteries are not available for CABG.


Assuntos
Pressão Sanguínea , Artérias Carótidas/imunologia , Moléculas de Adesão Celular/metabolismo , Ponte de Artéria Coronária/efeitos adversos , Veias Jugulares/imunologia , Animais , Adesão Celular , Moléculas de Adesão Celular/genética , Selectina E/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/metabolismo , Veias Jugulares/transplante , Leucócitos/imunologia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Perfusão , Fluxo Pulsátil , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Fatores de Tempo , Molécula 1 de Adesão de Célula Vascular/metabolismo
12.
Biomed Sci Instrum ; 47: 64-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21525598

RESUMO

A protocol for spin-casting uniform Poly(DL-lactide-co-glycolide) (PLGA) thin films was developed and a variety of known solvents were evaluated for their impact on the quality of the films produced. Film thickness was quantified using a reflectometer and the elastic moduli were determined using a wavelength bucking technique. Qualitative observations of the films’ morphological characteristics were made using optical microscopy. These parameters were then monitored over time as PLGA thin films were exposed to mildly agitated aqueous buffer solutions at 37 °C. Initial results suggest that over the course of several weeks films undergo a reduction in thickness with a concomitant change in film morphology. Current efforts are focused on determining how the changes in the mechanical properties of these films are correlated with the degradation process, in order to elucidate the mechanism and provide guidance on the use of PLGA in biological applications involving mechanical stresses.

13.
Health SA Gesondheid (Print) ; 15(1): 1-7, 2010.
Artigo em Inglês | AIM (África) | ID: biblio-1262463

RESUMO

Clinical community health facilities where undergraduate students are placed for their practical work in community nursing science are dynamic and have undergone major transformation over the past few years. In the clinical field; community nurses and undergraduate students are representative of the different races and language and ethnic groups in the South African population; with each group espousing different value systems. Both parties - students and community nurses - report that; due to these differences; value conflicts are experienced during clinical accompaniment and that this has negative effects on clinical learning in community nursing science. The goal of this study was to explore and describe the experiences of students with regard to value-sensitive clinical accompaniment in the community nursing environment. An exploratory; descriptive and contextual design was used. Interactions between community nurses and students during clinical accompaniment were explored for value sensitivity by means of video recordings; participant observation and focus group interviews. Data were collected by means of video recordings; participant observation and focus group interviews. The data were analysed and coded by the researcher and the external coder; using an inductive descriptive method to identify important segments of the regularity of behaviour. The focus group interviews were transcribed; analysed and coded by the researcher and the external coder; using Tesch's steps of analysis (Creswell 1994:155-156). Lincoln and Guba's criteria (1985:290) for trustworthiness were applied to the study. The general findings indicate that clinical accompaniment in community nursing is not value sensitive and; as a result; guidelines for value-sensitive clinical accompaniment need to be developed for undergraduate students in the community nursing environment. The following values (values for which guidelines need to be developed) were identified: respect during clinical accompaniment; value-sensitive communication and sensitivity to the quality of clinical accompaniment. People's thoughts often focus on the suicide victim immediately after a completed suicide. Yet; the real victims of such an event are those individuals who are left behind to cope with the aftermath of the suicide. This phenomenological psychological study explored the lived experiences of lateadolescent suicide survivors; particularly those negative experiences that seemed to worsen in the weeks and months after a significant other's completed suicide. The research participants were five female late-adolescents (aged 17-22 years) who were recruited by means of purposive sampling at a South African tertiary institution and at youth camps. Data collection consisted of collagefacilitated; face-to-face phenomenological interviews. In addition; some participants provided documentary material in the form of personal diaries; letters and poems. The data analysis was conducted according to Giorgi's phenomenological method. The following salient experiences emerged during the data analysis: guilt; self-blame; blaming others or God; anger; loss or restriction of 'self'; depression; suboptimal behavioural coping patterns; changes in relationship dynamics; and suicidality. The results of this study can be used by mental health professionals and caregivers to support adolescent suicide survivors effectively; in the midst of their mourning


Assuntos
Enfermagem em Saúde Comunitária , Cuidados Paliativos na Terminalidade da Vida , Competência Profissional , Estudantes
14.
Mol Ecol ; 18(12): 2615-27, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19457191

RESUMO

Theory predicts that reproductive isolation may be due to intrinsic genetic incompatibilities or extrinsic ecological factors. Therefore, an understanding of the genetic basis of isolation may require analyses of evolutionary processes in situ to include environmental factors. Here we study genetic isolation between populations of sculpins (Cottus) at 168 microsatellites. Genomic clines were fit using 480 individuals sampled across independent natural hybrid zones that have formed between one invading species and two separate populations of a resident species. Our analysis tests for deviations from neutral patterns of introgression at individual loci based on expectations given genome-wide admixture. Roughly 51% of the loci analysed displayed significant deviations. An overall deficit of interspecific heterozygotes in 26% and 21% of the loci suggests that widespread underdominance drives genomic isolation. At the same time, selection promotes introgression of almost 30% of the markers, which implies that hybridization may increase the fitness of admixed individuals. Cases of overdominance or epistatic interactions were relatively rare. Despite the similarity of the two hybrid zones in their overall genomic composition, patterns observed at individual loci show little correlation between zones and many fit different genotypic models of fitness. At this point, it remains difficult to determine whether these results are due to differences in external selection pressures or cryptic genetic differentiation of distinct parental populations. In the future, data from mapped genetic markers and on variation of ecological factors will provide additional insights into the contribution of these factors to variation in the evolutionary consequences of hybridization.


Assuntos
Peixes/genética , Genética Populacional , Hibridização Genética , Seleção Genética , Alelos , Animais , Evolução Molecular , Frequência do Gene , Marcadores Genéticos , Especiação Genética , Variação Genética , Repetições de Microssatélites , Modelos Genéticos , Reprodução/genética , Análise de Sequência de DNA
15.
Mol Biol Evol ; 26(4): 925-36, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19174479

RESUMO

Genomewide analyses of the transcriptome have confirmed that gene misexpression may underlie reproductive isolation mechanisms in interspecific hybrids. Here, using a 16,006 features cDNA microarray, we compared and contrasted gene expression divergence at two ontogenetic stages in incipient species of normal and dwarf whitefish (Coregonus clupeaformis) with that of first generation (normal x dwarf) and second-generation hybrid crosses (backcross: [normal x dwarf] x normal]. Our goal was to identify the main mode of action responsible for gene transcription and to discover key genes misexpressed in hybrids. Very few transcripts (five of 4,950 expressed) differed in mean expression level between parentals and hybrids at the embryonic stage, in contrast to 16-week-old juvenile fish for which 617 out of 5,359 transcripts differed significantly. We also found evidence for more misexpression in backcross hybrids whereby nonadditivity explained a larger fraction of hybrid inheritance patterns in backcross (54%) compared with F1-hybrids (9%). Gene expression in hybrids was more variable than in pure crosses and transgressive patterns of expression were ubiquitous in hybrids. In backcross embryos in particular, the expression of three key developmental genes involved in protein folding and mRNA translation was severely disrupted. Accordingly, gene misexpression in hybrids adds to other factors previously identified as contributing to the reproductive isolation of incipient species of lake whitefish.


Assuntos
Perfilação da Expressão Gênica , Salmonidae/genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Análise de Sequência com Séries de Oligonucleotídeos
16.
Health SA Gesondheid (Print) ; 13(1): 55-62, 2008.
Artigo em Inglês | AIM (África) | ID: biblio-1262413

RESUMO

The purpose of the study was to explore and describe experiences of mothers during childbirth in a tertiary hospital in the Limpopo Province. This was achieved through a qualitative research study which was exploratory; descriptive; contextual and inductive in nature. A sample of 24 mothers participated in this study. Data obtained from unstructured in-depth interviews were analysed according to the protocol by Tesch (1990; cited in Cresswell; 1994:155). Five themes were identified; namely mutual participation and responsibility sharing; dependency and decision-making; information sharing and empowering autonomy and informed choices; open communication and listening; accom -modative /non-accommodative midwifery actions; and maximising human and material infrastructure. The themes indicated experiences that foster or promote dependency on midwifery care. Guidelines on how to transform this dependency into a mother-centered care approach during childbirth are provided


Assuntos
Parto Obstétrico , Tocologia , Mães , Parto , Encaminhamento e Consulta
17.
Health SA Gesondheid (Print) ; 13(2): 61-73, 2008.
Artigo em Inglês | AIM (África) | ID: biblio-1262420

RESUMO

Although the prone positioning of a critically ill patient poses a challenge to nursing interventions; it remains the responsibility of nurses to develop a way to provide the same basic and intensive care to those patients lying prone as to those lying supine. The purpose of this study was firstly to conduct a systematic review of the literature as explora-tion and description of the evidence in support of the beneficial nursing interventions during prone positioning of ventilated patients; and secondly to develop evidence-based nursing guidelines for the nursing process. This exploratory; descriptive and retrospective systematic review includes data from 45 clinical trials; with a total population of 2 148 patients. Data was extracted onto data abstraction forms; assessed for methodological quality and finally summarised in evidence tables. All statistical calculations for the meta-analysis were performed by the RevMan 4.2.8 program. Prone positioning showed significant (p 0.0001) increases in the partial pressure of oxygen in arterial blood (PaO2) weighted mean difference (WMD CI = 11.36; 31.8). The effects of complications; oxygenation and haemodynamic outcomes compared with the different prone-positioning protocols produced in conclusive results. Nursing guidelines for prone positioning were developed based on the best available evidence. The lack of related articles on nursing care of prone positioning was a drawback. Based on these results; recommendations are made towards further study on the nursing care of prone-positioned patients


Assuntos
Cuidados Críticos , Estado Terminal , Medicina Baseada em Evidências , Enfermagem , Revisão
18.
Health SA Gesondheid (Print) ; 12(2): 3-13, 2007.
Artigo em Inglês | AIM (África) | ID: biblio-1262388

RESUMO

The purpose of this study was to explore and describe the experiences of mothers who lost a baby during pregnancy and care given by doctors and midwives during this period. To realise this goal the researcher followed a qualitative; exploratory; descriptive and contextual approach. Data were collected by using in-depth unstructured interviews. The interviews were taped and transcribed verbatim. Data were analysed through open coding. Data were collected until saturation had occurred. All mothers who were interviewed described their experiences of the loss of a baby during pregnancy. Some shared the same experiences and others did not. In the findings of this research; it became clear that mothers with the loss of a baby during pregnancy had experienced hardships and difficult times during this period. They expressed the wish that people acknowledge their loss; be considerate; sensitive; and give them a listening ear and emotional support. On the other hand; mothers identified the inability of health workers to give them the appropriate support


Assuntos
Morte Fetal , Mães , Gestantes
19.
Mol Ecol ; 15(7): 1983-93, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16689913

RESUMO

Hybrid zones are commonly studied to dissect the processes that drive divergence among lineages, which have incomplete barriers of reproduction. Most hybrid zones have existed for an extended time making inferences on the initial mode of formation difficult. It is a priori unclear how fast a nascent hybrid zone would form as a response to endogenous and exogenous factors. We have studied several hybrid zones between two lineages of sculpins (Cottus spp.), which emerged due to a recent range expansion of one of the lineages along the river Rhine in the early 1990s. Applying a dense sampling across two contact areas and using a highly informative set of 45 microsatellite markers we found pronounced genetic structure. Steep genetic clines suggest that strong selective forces have shaped the respective hybrid zones from the beginning. We find that the zones are coupled to ecological transitions from small streams to larger rivers. The width of these zones is much smaller than estimates of annual individual dispersal distances, as estimated outside of the hybrid zones. The pattern is apparently not strongly affected by pre- or postzygotic reproductive isolation because numerous backcross hybrids occur within the zones. This suggests that strong natural selection acts against immigrant genotypes. The study exemplifies how local adaptation can play a key role in preventing admixture in dependence of the ecological context.


Assuntos
Adaptação Fisiológica , Ecossistema , Peixes/fisiologia , Hibridização Genética , Animais , Peixes/classificação , Peixes/genética , Genótipo , Geografia , Comportamento de Retorno ao Território Vital , Repetições de Microssatélites , Rios , Seleção Genética , Análise de Sequência de DNA , Comportamento Sexual Animal
20.
J Evol Biol ; 18(6): 1619-24, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16313473

RESUMO

To initiate QTL studies in the nonmodel fish Cottus gobio we constructed a genetic map based on 171 microsatellite markers. The mapping panel consisted of F1 intercrosses between two divergent Cottus lineages from the River Rhine System. Basic local alignment search tool (BLAST) searches with the flanking sequences of the microsatellite markers yielded a significant (e < 10(-5)) hit with the Tetraodon nigroviridis genomic sequence for 45% of the Cottus loci. Remarkably, most of these hits were due to short highly conserved noncoding stretches. These have an average length of 40 bp and are on average 92% conserved. Comparison of the map locations between the two genomes revealed extensive conserved synteny, suggesting that the Tetraodon genomic sequence will serve as an excellent genomic reference for at least the Acanthopterygii, which include evolutionarily interesting fish groups such as guppies (Poecilia), cichlids (Tilapia) or Xiphophorus (Platy). The apparent high density of short conserved noncoding stretches in these fish genomes will highly facilitate the identification of genes that have been identified in QTL mapping strategies of evolutionary relevant traits.


Assuntos
Peixes/genética , Ligação Genética/genética , Mapeamento Físico do Cromossomo , Animais , Biologia Computacional , Cruzamentos Genéticos , Alemanha , Repetições de Microssatélites/genética , Filogenia , Locos de Características Quantitativas , Especificidade da Espécie
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