RESUMO
AIM: Despite the documented benefits of the World Health Organisation Patient Safety Checklist compliance rates with implementation continue to cause risk to patient safety. This qualitative systematic review aimed to explore the reported factors that impact compliance and implementation processes related to surgical safety checklists in perioperative settings. DESIGN: A qualitative systematic review. METHODS: A systematic review using the Joanna Briggs Institute (JBI) approach to synthesize qualitative studies was conducted and reported according to PRISMA guidelines. Electronic databases were expansively searched using keywords and subject headings. Articles were assessed using a pre-selected eligibility criterion. Data extraction and quality appraisal was undertaken for all included studies and a meta-aggregation performed. DATA SOURCES: The CINAHL, Medline and Scopus databases were searched in August 2022 and the search was repeated in June 2023. RESULTS: 34 studies were included. Following the synthesis of the findings there were multiple interrelating barriers to checklist compliance that impacted implementation. There were more barriers than enablers reported in existing studies. Enablers included effective leadership, education and training, timely use of audit and feedback, local champions, and the option for local modifications to the surgical checklist. Further research should focus on targeted interventions that improve observed compliance rates to optimize patient safety. CONCLUSION: This qualitative systematic review identified multiple key factors that influenced the uptake of the Surgical Safety Checklist in operating theatres. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Surgeon participation, hierarchical culture, complacency, and duplication of existing safety processes were identified which impacted the use and completion of the checklist.
Assuntos
Lista de Checagem , Cirurgiões , Humanos , Salas Cirúrgicas , Segurança do Paciente , Pesquisa QualitativaRESUMO
BACKGROUND: Children and young people affected by kidney failure experience complexities in their care. Little is known about the unique needs of this young patient population group living with a long-term condition. OBJECTIVE: A meta-aggregation of all qualitative studies was conducted to identify experiences of supportive care among children and young people living with kidney failure. METHODS: A systematic review of qualitative studies was conducted following the Joanna Briggs Institute meta-aggregation method. This review has been reported according to the PRISMA statement guidelines. Six electronic databases (CINAHL, Cochrane Library, MEDLINE, Proquest, PsycINFO, and Scopus) were comprehensively searched by an expert systematic review librarian using keywords and subject headings, from inception to September 2022. All studies were accessed using a predetermined inclusion and exclusion criteria. Methodological quality assessment and data extraction performed. Qualitative findings accompanied by illustrative quotes from included studies were extracted and grouped into categories which created the overall synthesised findings. RESULTS: A total of 34 studies were included in this review representing a total of 613 children and young people affected by kidney failure. There was a total of 190 findings which created 13 categories representing experiences of supportive care. The meta-aggregation developed five synthesised findings namely: 'physical needs', 'information and technology', 'treatment and healthcare', 'social needs' and 'psychological impacts'. CONCLUSION: This systematic review identified that children and young people affected by kidney failure can experience a range of unmet supportive care needs in routine clinical services. Kidney failure impacted children and young people's self-identify, social and peer networks, introduced daily practical needs because of inherent physical and psychological burden due to the failure and associated treatments. Despite improvements in the medical management of kidney failure in children and young people, further attention is needed to optimise supported self-management in this young patient group.
Assuntos
Pesquisa Qualitativa , Insuficiência Renal , Humanos , Criança , Insuficiência Renal/psicologia , Insuficiência Renal/terapia , Insuficiência Renal/complicações , Adolescente , Apoio SocialRESUMO
AIM: To explore the attitudes of vocational dental trainers (VDTs) working in general dental practice to the role of dental nurses as trainers and assessors of trainee dental nurses (tDNs), vocational dental practitioners (VDPs) and vocational dental hygienist/therapists (VDHTs). METHOD: This research was conducted within the context of the development of a training and assessment qualification for dental nurses. A survey was sent to all 148 VDTs in Scotland. The survey assessed VDT attitudes as to the appropriateness of dental nurses to train and assess tDNs, VDPs, VDHTs with regard to their clinical, communication-based and administrative duties. The three sets of attitudes for tDNS, VDPS and VDHTs were assessed on a five-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree). The data were subjected to one way and repeated measures of ANOVA. RESULTS: A total of 126 VDTs responded giving an 85% response rate. For clinical, communication-based and administrative activities, VDTs had significantly greater mean scores for the appropriateness of DNs to train [F(1,57) = 45.69, P < 0.001] and assess [F(1,57) = 76.94, P < 0.001] tDNs compared with VDPs and VDHTs. CONCLUSION: Vocational dental trainers felt it was more appropriate for DNs to train and assess tDNs' clinical, communication-based and administrative activities compared with VDPs and VDHTs. Over 80% of dental trainers, however, indicated there would be benefit to their practice in having a dental nurse educated in the principles and application of training and assessment.
Assuntos
Atitude do Pessoal de Saúde , Assistentes de Odontologia/educação , Avaliação Educacional/métodos , Ensino/métodos , Competência Clínica , Comunicação , Delegação Vertical de Responsabilidades Profissionais , Assistentes de Odontologia/psicologia , Auxiliares de Odontologia/educação , Higienistas Dentários/educação , Feminino , Odontologia Geral , Humanos , Masculino , Administração de Consultório , Escócia , Desenvolvimento de Pessoal , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Prostate cancer is the second most commonly diagnosed cancer globally. Cancer prehabilitation is defined as a process on the continuum of care that occurs between the time of a cancer diagnosis and the beginning of acute treatment. This article will discuss the importance of prostate cancer prehabilitation interventions in optimising physical and psychological recovery to enhance person-centred care. DATA SOURCES: Electronic databases including CINAHL, MEDLINE, PsychINFO, Scopus, professional websites, and grey literature were searched using Google Scholar. CONCLUSION: Prehabilitation in cancer care aims to enhance perioperative care and recovery. An emerging field of research suggests that the preoperative period may be physically and psychologically salient to introduce modifiable self-management behaviours to optimise overall recovery. IMPLICATIONS FOR NURSING PRACTICE: Prostate cancer specialist nurses provide the hub of person-centred care across the entire cancer care continuum embedded within the multidisciplinary team. Individually tailored interventions such as exercise and pelvic floor muscle training programmes, nutritional advice, anxiety and depression reduction, and sexual well-being interventions should be considered in the prehabilitation phase of the cancer care continuum.
Assuntos
Enfermagem Oncológica/métodos , Exercício Pré-Operatório , Neoplasias da Próstata/enfermagem , Humanos , Masculino , Assistência Centrada no Paciente/métodos , Neoplasias da Próstata/psicologiaRESUMO
The ability of intestinal mucosa to absorb dietary ferric iron is attributed to the presence of a brush-border membrane reductase activity that displays adaptive responses to iron status. We have isolated a complementary DNA, Dcytb (for duodenal cytochrome b), which encoded a putative plasma membrane di-heme protein in mouse duodenal mucosa. Dcytb shared between 45 and 50% similarity to the cytochrome b561 family of plasma membrane reductases, was highly expressed in the brush-border membrane of duodenal enterocytes, and induced ferric reductase activity when expressed in Xenopus oocytes and cultured cells. Duodenal expression levels of Dcytb messenger RNA and protein were regulated by changes in physiological modulators of iron absorption. Thus, Dcytb provides an important element in the iron absorption pathway.
Assuntos
Grupo dos Citocromos b/metabolismo , Duodeno/metabolismo , Compostos Férricos/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Ferro da Dieta/metabolismo , Oxirredutases/metabolismo , Transfecção , Sequência de Aminoácidos , Anemia/enzimologia , Animais , Linhagem Celular , Clonagem Molecular , Grupo dos Citocromos b/química , Grupo dos Citocromos b/genética , DNA Complementar , Duodeno/enzimologia , Enterócitos/enzimologia , Enterócitos/metabolismo , Indução Enzimática , Hipóxia , Mucosa Intestinal/enzimologia , Ferro da Dieta/administração & dosagem , Masculino , Camundongos , Microvilosidades/enzimologia , Microvilosidades/metabolismo , Dados de Sequência Molecular , Nitroazul de Tetrazólio/metabolismo , Oócitos , Oxirredução , Oxirredutases/química , Oxirredutases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Regulação para Cima , XenopusRESUMO
BACKGROUND AND AIMS: Total body iron and high dietary iron intake are risk factors for colorectal cancer. To date there is no comprehensive characterisation of iron transport proteins in progression to colorectal carcinoma. In this study, we examined expression of iron import (duodenal cytochrome b (DCYTB), divalent metal transporter 1 (DMT1), and transferrin receptor 1 (TfR1)) and export (hephaestin (HEPH) and ferroportin (FPN)) proteins in colorectal carcinoma. METHODS: Perl's staining was used to examine colonocyte iron content. Real time polymerase chain reaction (PCR) and western blotting were used to examine mRNA and protein levels of the molecules of interest in 11 human colorectal cancers. Semiquantitative immunohistochemistry was used to verify protein levels and information on cellular localisation. The effect of iron loading on E-cadherin expression in SW480 and Caco-2 cell lines was examined by promoter assays, real time PCR and western blotting. RESULTS: Perl's staining showed increased iron in colorectal cancers, and there was a corresponding overexpression of components of the intracellular iron import machinery (DCYTB, DMT1, and TfR1). The iron exporter FPN was also overexpressed, but its intracellular location, combined with reduced HEPH levels, suggests reduced iron efflux in the majority of colorectal cancers examined. Loss of HEPH and FPN expression was associated with more advanced disease. Iron loading Caco-2 and SW480 cells caused cellular proliferation and E-cadherin repression. CONCLUSIONS: Progression to colorectal cancer is associated with increased expression in iron import proteins and a block in iron export due to decreased expression and aberrant localisation of HEPH and FPN, respectively. This results in increased intracellular iron which may induce proliferation and repress cell adhesion.
Assuntos
Caderinas/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Ligação ao Ferro/metabolismo , Ferro/metabolismo , Antígenos CD/metabolismo , Células CACO-2 , Proteínas de Transporte de Cátions/metabolismo , Adesão Celular/fisiologia , Proliferação de Células , Neoplasias Colorretais/etiologia , Grupo dos Citocromos b/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Oxirredutases/metabolismo , Receptores da Transferrina/metabolismoRESUMO
AIMS: To assess the spontaneous resolution of neonatal nephrocalcinosis and its long term effects on renal function. METHODS: Fourteen very low birthweight preterm babies with nephrocalcinosis were followed up at 5-7 years of age; 14 controls were matched for sex, gestation, and birth weight. Height, weight, blood pressure, and renal symptomatology were recorded, and a renal ultrasound scan was performed. Early morning urine osmolality and creatinine ratios of albumin, phosphate, calcium, oxalate and beta microglobulin were determined. Urea and electrolytes in the study group were determined, and glomerular filtration rate (GFR) and TmP/GFR (tubular reabsorption of phosphate per GFR) were calculated. Statistical analysis was performed on a group basis using the Mann-Whitney confidence interval. RESULTS: Mean age was 6.9 years (range 5.81-7.68). An early morning urine osmolality >700 mOsm/kg was achieved in all cases. In two cases and four controls, the calcium/creatinine ratio was >0.7 mmol/mmol. In all cases, the GFR was normal (median 132.6 ml/min/1.73 m(2) (range 104.1-173.1)). Median TmP/GFR was 1.22 mmol/l (0.73-1.61), with two having levels below the normal range. These did not have persisting nephrocalcinosis. Nephrocalcinosis was found in three of the 12 cases scanned and one control. There were no significant differences in urine biochemistry. CONCLUSIONS: Resolution of nephrocalcinosis occurred in 75% of cases. No evidence was found to suggest that nephrocalcinosis is associated with renal dysfunction in the long term. There was evidence of hypercalciuria in the cases and controls, suggesting that prematurity may be a risk factor.
Assuntos
Doenças do Prematuro/diagnóstico , Nefrocalcinose/diagnóstico , Peso ao Nascer , Cálcio/urina , Estudos de Casos e Controles , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico por imagem , Doenças do Prematuro/fisiopatologia , Recém-Nascido de muito Baixo Peso , Rim/diagnóstico por imagem , Rim/patologia , Rim/fisiopatologia , Masculino , Nefrocalcinose/diagnóstico por imagem , Nefrocalcinose/fisiopatologia , Concentração Osmolar , Prognóstico , UltrassonografiaRESUMO
The normally acidic mucosal surface pH of 6.24 +/- 0.02(30) in rat proximal jejunum in vivo is effectively neutralised by 30 min exposure to heat-stable Escherichia coli (STa) enterotoxin (14 micrograms/ml) to 6.80 +/- 0.07 (n = 5) or to a forskolin/theophylline combination (1 mM:20 mM) to 7.10 +/- 0.07(7) while perfusion with Krebs-phosphate buffer alone without glucose left the mucosal surface pH unchanged at a pH of 6.21 +/- 0.02(9). Forskolin alone had no effect, and 20 mM theophylline moderately elevated the surface pH to 6.52 +/- 0.03(5). Theophylline, forskolin and their combination all elevated cAMP levels per mg tissue DNA above control values while STa enterotoxin was without effect. In contrast, all agents elevated cGMP levels per mg tissue DNA above control levels. These findings indicate that surface pH is only moderately affected by changes in cAMP levels and is affected to a much greater extent by altered cGMP levels.
Assuntos
Toxinas Bacterianas/farmacologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Enterotoxinas/farmacologia , Mucosa Intestinal/fisiologia , Jejuno/fisiologia , Teofilina/farmacologia , Animais , Condutividade Elétrica , Proteínas de Escherichia coli , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Jejuno/efeitos dos fármacos , Jejuno/metabolismo , Cinética , Ratos , Ratos Endogâmicos , Valores de ReferênciaRESUMO
Iron metabolism in animals is altered by haemolytic anaemia induced by phenylhydrazine (PHZ). In common with a number of other modulators of iron metabolism, the mode and the mechanisms of this response are yet to be determined. However, recent studies have shown increased expression of the ferrous transporter DMT1 in the duodenum and other tissues of mice administered PHZ. We examined the expression of the ferric reductase Dcytb, DMT1 and some other genes involved in Fe metabolism in tissues of mice dosed with PHZ. The expression of iron-related genes in the duodenum, liver, and spleen of the mice were evaluated using Northern blot analyses, RT-PCR and immunocytochemistry. Dcytb, and DMT1 mRNA and protein increased markedly in the duodenum of mice given PHZ. The efflux protein Ireg1 also increased in the duodenum of the treated mice. These changes correlated with a decrease in hepatic hepcidin expression. Dcytb, DMT1, Ireg1 and transferrin receptor 1 mRNA expression in the spleen and liver of mice treated with PHZ responded to the enhanced iron demand associated with the resulting stimulation of erythropoiesis. Enhanced iron absorption observed in PHZ-treated animals is facilitated by the up-regulation of the genes involved in iron transport and recycling. The probable association of the erythroid and the store regulators of iron homeostasis and absorption in the mice is discussed.
Assuntos
Ferro/metabolismo , Fenil-Hidrazinas/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Transporte Biológico , Northern Blotting , Proteínas de Transporte de Cátions/metabolismo , Grupo dos Citocromos b/metabolismo , FMN Redutase/metabolismo , Hemólise , Hepcidinas , Imuno-Histoquímica , Camundongos , Oxirredutases/metabolismo , RNA Mensageiro/metabolismo , Receptores da Transferrina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição TecidualRESUMO
Iron has a variety of functions in cellular organisms ranging from electron transport and DNA synthesis to adenosine triphosphate (ATP) and neurotransmitter synthesis. Failure to regulate the homeostasis of iron can lead to cognition and demyelination disorders when iron levels are deficient, and to neurodegenerative disorders when iron is in excess. In this study we show that three members of the b561 family of predicted ferric reductases, namely mouse cytochrome b561 and mouse and fly stromal cell-derived receptor 2 (SDR2), have ferric reductase activity. Given that a fourth member, duodenal cytochrome b (Dcytb), has previously been shown to be a ferric reductase, it is likely that all remaining members of this family also exhibit this activity. Furthermore, we show that the rat sdr2 message is predominantly expressed in the liver and kidney, with low expression in the duodenum. In hypotransferrinaemic (hpx) mice, sdr2 expression in the liver and kidney is reduced, suggesting that it may be regulated by iron. Moreover, we demonstrate the presence of mouse sdr2 in the choroid plexus and in the ependymal cells lining the four ventricles, through in situ hybridization analysis.
Assuntos
Grupo dos Citocromos b/metabolismo , FMN Redutase/metabolismo , Oxirredutases/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Grupo dos Citocromos b/genética , FMN Redutase/genética , Feminino , Humanos , Hibridização In Situ , Ferro/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Família Multigênica , Oócitos/fisiologia , Oxirredutases/genética , Ratos , Receptores de Superfície Celular/genética , Distribuição Tecidual , Xenopus laevisRESUMO
BACKGROUND: Human cytomegalovirus (CMV) infection is a major cause of morbidity in transplant patients. Early diagnosis and treatment have been shown to improve outcome. We evaluated the suitability of CMV immediate early, early, and late gene expression detected by nucleic acid sequence-based amplification (NASBA) as markers of CMV infection. METHODS: Blood samples were taken immediately before transplant and every one to two weeks after transplantation for 12 weeks from 50 patients undergoing thoracic organ transplantation. CMV-NASBA was performed and results compared with serology, CMV pp65 antigenaemia (CMV-AG) and the development of clinical CMV infection. Patients received "preemptive" anti-CMV therapy with ganciclovir based on the CMV-AG results. RESULTS: CMV immediate early and early gene expression were detected in 87 and 47%, respectively, of patients without other evidence of CMV infection. CMV late gene expression had a sensitivity of 97% for infection (compared with 83% for CMV-AG P=0.06) and a specificity of 93% (compared with 100% P=NS). Late gene expression occurred at the same time as CMV antigenaemia but 1.1 weeks earlier than the threshold of antigenaemia (CMV-AG>10) used to initiate preemptive therapy. CONCLUSION: NASBA provided a standardized tool for the detection of CMV transcripts with a greater sensitivity than the standard antigenemia test. Detection of immediate early and early gene transcripts was not specific for subsequent infection. CMV late gene expression determined by NASBA was an accurate and early marker of CMV infection. Detection of CMV late gene expression could be used to trigger "preemptive" anti-CMV therapy.
Assuntos
Citomegalovirus/genética , Genes Virais/genética , Transplante de Coração , Transplante de Coração-Pulmão , Transplante de Pulmão , Replicação de Sequência Autossustentável/métodos , Adulto , Antivirais/uso terapêutico , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/imunologia , Feminino , Ganciclovir/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Transcrição GênicaRESUMO
Placental pregnancy-associated plasma protein-A (PAPP-A) mRNA expression, placental PAPP-A protein concentration and maternal serum levels of PAPP-A were examined in pregnancies affected by trisomy 21 (n=8), trisomy 18 (n=7) and 15 normal controls at 12-15 weeks of gestation. The maternal serum concentration of PAPP-A in the trisomic group of pregnancies was significantly lower than in the normal controls. However there were no significant differences between the three groups in PAPP-A mRNA expression or PAPP-A protein concentration in the placental tissues. There was no significant association between the level of placental mRNA and either placental protein or maternal serum PAPP-A concentrations in the normal or trisomic pregnancies. There was however a significant association between placental protein and maternal serum PAPP-A concentrations in the normal and trisomy 21 pregnancies but not in those affected by trisomy 18. These findings suggest that the decrease in maternal serum PAPP-A in trisomic pregnancies is due to alternations in post-translational events such as protein stability, alterations in the release mechanism of the protein, impaired protein transport across the placenta or modified serum stability of PAPP-A.
Assuntos
Expressão Gênica , Placenta/metabolismo , Proteína Plasmática A Associada à Gravidez/genética , Trissomia , Cromossomos Humanos Par 18 , Síndrome de Down/genética , Feminino , Humanos , Gravidez , Proteína Plasmática A Associada à Gravidez/metabolismo , RNA Mensageiro/metabolismoRESUMO
OBJECTIVE: To investigate whether the increased nuchal translucency of trisomic fetuses is the consequence of heart failure by examining cardiac expression of atrial natriuretic peptide and brain natriuretic peptide genes. METHODS: Cardiac atrial natriuretic peptide and brain natriuretic peptide messenger RNA (mRNA) levels were measured in fetal hearts from 15 pregnancies affected by trisomy 21 or 18 at 12-16 weeks' gestation and from 30 normal controls at 10-20 weeks. RESULTS: In normal fetuses, mRNA levels of atrial natriuretic peptide decreased, but levels of brain natriuretic peptide did not change significantly with gestation. In trisomic fetuses, mRNA levels of both atrial natriuretic peptide and brain natriuretic peptide were significantly higher than in gestational age-matched normal controls. CONCLUSION: These data demonstrate that atrial natriuretic peptide and brain natriuretic peptide genes are transcribed prenatally, and the findings in trisomic fetuses suggest that the increased translucency of trisomic fetuses may be the consequence of heart failure.
Assuntos
Fator Natriurético Atrial/genética , Síndrome de Down/genética , Coração Fetal/química , Proteínas do Tecido Nervoso/genética , Trissomia , Adulto , Biomarcadores/análise , Feminino , Idade Gestacional , Humanos , Peptídeo Natriurético Encefálico , RNA Mensageiro/análise , Transcrição GênicaRESUMO
The mucosal surface pH (acid microclimate) and nucleotide levels of rat proximal jejunum were measured in vivo under various conditions which included exposure to pharmacological agents and to surfactants. Mucosal surface pH was unaffected by sodium nitroprusside, A23187 and amiloride, as was mucosal cGMP content, although amiloride and A23187 reduced cAMP content. In contrast, surfactants elevated the pH of the mucosal surface significantly (P less than 0.001): control value 6.23 +/- 0.02 (n = 12); Lubrol PX 0.8% (v/v) 6.98 +/- 0.02 (n = 5); sodium deoxycholate 2 mmol/l 6.67 +/- 0.04 (n = 5); Triton X-100 0.5% (v/v) 7.41 +/- 0.03 (n = 5). No significant changes in cGMP levels were noted after surfactant treatment, although DOC and Triton X-100 reduced cAMP levels. The ability of higher concentrations of surfactant to elevate the mucosal surface pH beyond neutrality to values similar to plasma pH contrasts with the action of Escherichia coli heat-stable (STa) enterotoxin which at high concentrations could not elevate the mucosal surface pH beyond neutrality. Consistent with the known effects on tight junction permeability, surfactants may act by allowing plasma-like subepithelial fluid to neutralise the microclimate.
Assuntos
Ácido Desoxicólico/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Tensoativos/farmacologia , Amilorida/farmacologia , Animais , Toxinas Bacterianas/farmacologia , Calcimicina/farmacologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Ácido Dioctil Sulfossuccínico/farmacologia , Enterotoxinas/farmacologia , Proteínas de Escherichia coli , Concentração de Íons de Hidrogênio , Mucosa Intestinal/química , Jejuno/química , Jejuno/metabolismo , Masculino , Nitroprussiato/farmacologia , Polietilenoglicóis/farmacologia , Radioimunoensaio , Ratos , Ratos EndogâmicosRESUMO
Nickel exhibits low oral toxicity. It shares the absorptive pathways for iron, though there are substantial quantitative differences in handling of both metals. To analyse these differences more closely, jejunal segments from iron-deficient and iron-adequate rats were luminally perfused ex vivo with 59Fe and 63Ni at six different concentrations (1-500 micromo1/l) under steady state conditions. 59Fe over-all absorption increased 2.0-4.6-fold in iron-deficiency at luminal concentrations between 1 and 100 micromol/l, while 63Ni absorption increased to a much lower extent (2.6-fold at 1 micromol/l and 1.5-fold at higher luminal concentrations). Moreover, there was a 5-7-fold higher concentration for 63Ni in the jejunal tissue than in the absorbate at luminal concentrations above 50 micromol/l which was not observed at 1 micromol 63Ni/l and not for 59Fe. 63Ni tissue load showed a linear and a saturable fraction. In iron-deficiency the saturable 63Ni fraction increased 4-fold as compared to only 1.5-fold increments for 59Fe. Moreover, a substantially higher share of 63Ni was retained in the jejunal tissue at high as compare to low luminal concentrations after perfusion had been continued without luminal radioactivity. This was not found for 59Fe and suggests a concentration-dependent block of 63Ni export across the enterocytes' basolateral membrane. To explain these results one may speculate that 63Ni may bind more tightly to tissue ligands than 59Fe due to the higher thermodynamic and kinetic stability of nickel complexes. In particular, nickel may bind to a basolateral population of metal carriers and block its own basolateral transfer in a concentration-dependent manner. Tight 63Ni binding to non-specific jejunal ligands is responsible for the unaltered high linear fraction of jejunal 63Ni load in iron-deficient and iron-adequate segments. Binding of 63Ni to food and tissue ligands in the small intestine may, thus, be a likely explanation for the low oral nickel toxicity.
Assuntos
Absorção Intestinal , Ferro da Dieta , Ferro , Jejuno/metabolismo , Níquel/metabolismo , Animais , Transporte Biológico Ativo , Relação Dose-Resposta a Droga , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Ferro/administração & dosagem , Ferro/metabolismo , Deficiências de Ferro , Radioisótopos de Ferro , Masculino , Perfusão , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
In this study we examined alpha-fetoprotein (AFP) mRNA expression in fetal liver at 12-15 weeks of gestation in trisomy 21 (n = 13), trisomy 18 (n = 5) and control fetuses (n = 24). No significant difference was found in the steady-state level of fetal liver AFP mRNA levels in either of the two trisomy groups studied. These findings suggest that the decrease in maternal serum AFP concentration found in trisomic pregnancies is unlikely to be the consequence of impaired transcription of the AFP gene by the fetal liver.
Assuntos
Cromossomos Humanos Par 18 , Síndrome de Down/metabolismo , Fígado/embriologia , RNA Mensageiro/análise , Trissomia , alfa-Fetoproteínas/genética , Northern Blotting , Feminino , Expressão Gênica , Idade Gestacional , Humanos , Fígado/química , Fígado/metabolismo , Gravidez , RNA Mensageiro/metabolismoRESUMO
In this paper, the authors address the serious neglect of the 'classical' virtues in ethical reflection upon mental health nursing. The virtues are offered as a possible alternative paradigm for mental health nursing in its search for new models and approaches. Embodied in the notion of a moral community, the virtues have important implications in addressing problems adherent in various 'dualisms' so described. By invoking the concepts of practical wisdom and praxis, the interrelationship between theory and practice, action and reflection and self and community, is shown. The contextual nature of the virtues is shown in a number of examples and their potential for the transformation of practice is shown. The opportunity is now present for mental health nursing to strengthen its basis for practice by distancing itself from scientific models. In so doing, it can embrace an approach which is consensual and contextual and which places ethical reflection at the centre of practice.
Assuntos
Caráter , Ética em Enfermagem , Filosofia em Enfermagem , Enfermagem Psiquiátrica/organização & administração , Valores Sociais , Empatia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Conhecimento , Modelos de Enfermagem , Relações Enfermeiro-Paciente , Cultura Organizacional , Defesa do Paciente , CiênciaRESUMO
The increasing use of the humanities in nurse education provides an alternative means of facilitating students' understanding of health issues. In part, this contributes to a critique of rationalist-technological approaches to education where knowledge is reduced to abstract, discernable and measured units. A more communal approach to education recognises the place of interpretation as part of learning and, within this, the significance of dialogue, identity, tradition, attachment and partnership. The reading of works of literature is one way in which the reader interprets texts in a multiplicity of ways in order to more fully understand the 'real' world. Mental health offers particular opportunities for literary descriptions. The evaluation of a learning unit within a mental health nursing branch programme where students read a number of works of literature is outlined. Results indicate a variety of student responses to use of such an approach. The authors assert the usefulness of these approaches in encouraging deeper understanding of complex issues faced in mental health nursing practice. At the same time, however, careful consideration is given to the place of such approaches within the overall philosophy of a curriculum programme.
Assuntos
Literatura , Enfermagem Psiquiátrica/educação , Ensino/métodos , Humanos , Aprendizagem , Modelos EducacionaisRESUMO
The concepts of collaboration and partnership currently have extensive impact upon health care providers and higher education institutions. One of the challenges is to develop networks which will foster partnerships able to react, and contribute, to an ever-evolving educational culture. These themes are illustrated by using the example of one school of nursing and midwifery, and the collective experience of a number of its academic staff. By focusing on distinct features of collaboration (strategic planning, origins of change, group dynamics and building a community), the authors seek to explore the impact of an educational culture in an attempt to provide meaning to their recent experiences. In so doing, group identity is explored and the prospect for creating partnerships across disciplines ('similarities rather than differences') is considered.
Assuntos
Docentes de Enfermagem/organização & administração , Relações Interprofissionais , Cultura Organizacional , Processos Grupais , Humanos , Inovação Organizacional , EscóciaRESUMO
This paper explores themes relevant to mental health nursing using the example of one educational module of a nursing degree. The authors argue that the educational preparation of mental health nursing students in higher education must address certain contested philosophical, conceptual, social and ethical dimensions of contemporary mental health care practice. These themes are discussed within the context of a third-year mental health nursing module within a Scottish nursing degree programme. By interlinking epistemology and ontology, the notion of student as 'critical practitioner', involving the encouragement of 'critical thinking', is developed. This is shown via engagement with parallel perspectives of the sciences and the humanities in mental health. Narratives of student nurse engagement with selected literary texts demonstrate the extent to which issues of knowledge, self-awareness and personal development are central to a student's professional journey as they progress through an academic course. The paper concludes by suggesting that these 'critical perspectives' have important wider implications for curriculum design in nursing education. Insights from critical theory can equip nurse educators to challenge consumerist tendencies within contemporary higher education by encouraging them to remain knowledgeable, critical and ethically sensitive towards the needs of their students.