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1.
J Eat Disord ; 11(1): 221, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082362

RESUMO

Two decades have elapsed since our publication of 'What kind of illness is anorexia nervosa?'. The question remains whether our understanding of anorexia nervosa and its treatment thereof has evolved over this time. The verdict is disappointing at best. Our current gold standard treatments remain over-valued and clinical outcomes are modest at best. Those in our field are haunted by the constant reminder that anorexia nervosa carries the highest mortality rate of any psychiatric disorder. This cannot continue and demands immediate action. In this essay, we tackle the myths that bedevil our field and explore a deeper phenotyping of anorexia nervosa. We argue that we can no longer declare agnostic views of the disorder or conceive treatments that are "brainless": it is incumbent upon us to challenge the prevailing zeitgeist and reconceptualise anorexia nervosa. Here we provide a roadmap for the future.

2.
Mol Hum Reprod ; 25(1): 30-41, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30395244

RESUMO

STUDY QUESTION: Can 13C-Magnetic Resonance Spectroscopy (MRS) of selected metabolites provide useful information about human sperm metabolism and how glycolysis or oxidative phosphorylation are used by different sperm populations? SUMMARY ANSWER: Sperm populations, prepared by density gradient centrifugation (DGC) and incubated with either 13Cu-glucose, 13Cu-fructose or 13C1-pyruvate, showed consistent evidence of metabolism generating principally lactate and more intermittently bicarbonate, and significantly more lactate was produced from 13Cu-glucose by vital or motile sperm recovered from the 40/80% interface compared to those from the pellet, which could not be accounted for by differences in the non-sperm cells present. WHAT IS KNOWN ALREADY: Previous studies have focused on CO2 or other specific metabolite production by human sperm and there remains considerable debate about whether glycolysis and/or oxidative phosphorylation is the more important pathway for ATP production in sperm. STUDY DESIGN, SIZE, DURATION: Sperm populations were prepared by DGC and subjected to 13C-MRS to answer the following questions. (i) Is it possible to detect human sperm metabolism of 13C substrates implicated in energy generation? (ii) What are the kinetics of such reactions? (iii) Do different sperm populations (e.g. '80%' pellet sperm and '40%' interface sperm) utilise substrates in the same way? Semen samples from 97 men were used in these experiments; 52 were used in parallel for aims (i) and (ii) and 45 were used for aim (iii). PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm populations were prepared from ejaculates of healthy men using a Percoll/Phosphate Buffered Saline (PBS) DGC and then incubated with a range of 13C-labelled substrates (13Cu-glucose, 13Cu-fructose, 13C1-pyruvate, 13C1-butyrate, 13C3-lactate, 13C2,4-D-3-hydroxybutyrate, 13C5-l-glutamate, 13C1,2-glycine or 13Cu-galactose) along with penicillin/streptomycin antibiotic at 37°C for 4 h, 24 h or over 48 h for an estimated rate constant. Sperm concentration, vitality and motility were measured and, for a subset of experiments, non-sperm cell concentration was determined. A 9.4 T magnetic resonance spectrometer was used to acquire 1D 13C, inverse gated 1H decoupled, MRS spectra. Spectrum processing was carried out using spectrometer software and Matlab scripts to determine peak integrals for each spectrum. MAIN RESULTS AND THE ROLE OF CHANCE: 13Cu-glucose, 13Cu-fructose and 13C1-pyruvate were consistently converted into lactate and, to a lesser extent, bicarbonate. There was a significant correlation between sperm concentration and lactate peak size for 13Cu-glucose and 13Cu-fructose, which was not observed for 13C1-pyruvate. The lactate peak did not correlate with the non-sperm cell concentration up to 6.9 × 106/ml. The concentration of 13Cu-glucose, 13Cu-fructose or 13C1-pyruvate (1.8, 3.6, 7.2 or 14.4 mM) had no influence on the size of the observed lactate peak over a 4 h incubation. The rate of conversion of 13C1-pyruvate to lactate was approximately three times faster than for 13Cu-glucose or 13Cu-fructose which were not significantly different from each other. After incubating for 4 h, the utilisation of 13Cu-glucose, 13Cu-fructose or 13C1-pyruvate by sperm from the '40%' interface of the DGC was no different from those from the pellet when normalised to total sperm concentration. However, after normalising by either the vital or motile sperm concentration, there was a significant increase in conversion of 13Cu-glucose to lactate by '40%' interface sperm compared to pellet sperm (Vital = 3.3 ± 0.30 × 106 vs 2.0 ± 0.21 × 106; P = 0.0049; Motile = 7.0 ± 0.75 × 106 vs 4.8 ± 0.13 × 106; P = 0.0032. Mann-Whitney test P < 0.0055 taken as statistically significant). No significant differences were observed for 13Cu-fructose or 13C1-pyruvate. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Only 13C labelled metabolites that accumulate to a sufficiently high concentration can be observed by 13C MRS. For this reason, intermediary molecules in the metabolic chain are difficult to observe without trapping the molecule at a particular step using inhibitors. Non-sperm cell concentration was typical of the general population and no link was found between these cells and the magnitude of the 13C-lactate peak. However, it is possible that higher concentrations than the maximum observed (6.9 × 106/ml) may contribute to exogenous substrate metabolism in other experiments. WIDER IMPLICATIONS OF THE FINDINGS: 13C-MRS can provide information on the underlying metabolism of multiple pathways in live sperm. Dysfunction in sperm metabolism, as a result of either impaired enzymes of lack of metabolisable substrate, could be detected in sperm by a non-destructive assay, potentially offering new treatment options to improve overall sperm quality and outcomes for reproduction. STUDY FUNDING AND COMPETING INTERESTS: This work was supported by the Medical Research Council Grant MR/M010473/1. The authors declare no conflicts of interest.


Assuntos
Isótopos de Carbono/análise , Espectroscopia de Ressonância Magnética/métodos , Espermatozoides/metabolismo , Centrifugação com Gradiente de Concentração , Ciclo do Ácido Cítrico/genética , Ciclo do Ácido Cítrico/fisiologia , Glicólise/genética , Glicólise/fisiologia , Humanos , Masculino
3.
Mol Hum Reprod ; 23(7): 441-451, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28431025

RESUMO

STUDY QUESTION: Can 1H Magnetic Resonance Spectroscopy (MRS) be used to obtain information about the molecules and metabolites in live human spermatozoa? SUMMARY ANSWER: Percoll-based density gradient centrifugation (DGC) followed by a further two washing steps, yielded enough sperm with minimal contamination (<0.01%) from seminal fluid to permit effective MRS which detected significant differences (P < 0.05) in the choline/glycerophosphocholine (GPC), lipid and lactate regions of the 1H MRS spectrum between sperm in the pellet and those from the 40%/80% interface. WHAT IS KNOWN ALREADY: Current methods to examine sperm are either limited in their value (e.g. semen analysis) or are destructive (e.g. immunohistochemistry, sperm DNA testing). A few studies have previously used MRS to examine sperm, but these have either looked at seminal plasma from men with different ejaculate qualities or at the molecules present in pooled samples of lyophilized sperm. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: Sperm suspended in phosphate buffered saline (PBS) at 37°C were examined by 1H MRS scanning using a 1H excitation-sculpting solvent suppression sequence after recovery from fresh ejaculates by one of three different methods: (i) simple centrifugation; (ii) DGC with one wash; or (iii) DGC with two washes. In the case of DGC, sperm were collected both from the pellet ('80%' sperm) and the 40/80 interface ('40%' sperm). Spectrum processing was carried out using custom Matlab scripts to determine; the degree of seminal plasma/Percoll contamination, the minimum sperm concentration for 1H MRS detection and differences between the 1H MRS spectra of '40%' and '80%' sperm. MAIN RESULTS AND THE ROLE OF CHANCE: DGC with two washes minimized the 1H MRS peak intensity for both seminal plasma and Percoll/PBS solution contamination while retaining sperm specific peaks. For the MRS scanner used in this study, the minimum sperm concentration required to produce a choline/GPC 1H MRS peak greater than 3:1 signal to noise ratio (SNR) was estimated at ~3 × 106/ml. The choline/GPC and lactate/lipid regions of the 1H spectrum were significantly different by two-way ANOVA analysis (P < 0.0001; n = 20). ROC curve analysis of these region showed significant ability to distinguish between the two sperm populations: choline/GPC ROC AUC = 0.65-0.67, lactate/lipid ROC AUC = 0.86-0.87. LIMITATIONS, REASONS FOR CAUTION: Only 3-4 semen samples were used to assess the efficacy of each sperm washing protocol that were examined. The estimated minimum sperm concentration required for MRS is specific to the hardware used in our study and may be different in other spectrometers. Spectrum binning is a low resolution analysis method that sums MRS peaks within a chemical shift range. This can obscure the identity of which metabolite(s) are responsible for differences between sperm populations. Further work is required to determine the relative contribution of somatic cells to the MRS spectrum from the '40%' and '80%' sperm. WIDER IMPLICATIONS OF THE FINDINGS: 1H MRS can provide information about the molecules present in live human sperm and may therefore permit the study of the underlying functional biology or metabolomics of live sperm. Given the relatively low concentration of sperm required to obtain a suitable MRS signal (~3 × 106/ml), this could be carried out on sperm from men with oligo-, astheno- or teratozoospermia. This may lead to the development of new diagnostic tests or ultimately novel treatments for male factor infertility. STUDY FUNDING AND COMPETING INTEREST(S): This work was supported by the Medical Research Council Grant MR/M010473/1. The authors declare no conflicts of interest.


Assuntos
Colina/análise , Glicerilfosforilcolina/análise , Ácido Láctico/análise , Espectroscopia de Ressonância Magnética/métodos , Análise do Sêmen/métodos , Espermatozoides/química , Adulto , Centrifugação com Gradiente de Concentração/métodos , Humanos , Espectroscopia de Ressonância Magnética/instrumentação , Masculino , Curva ROC , Sêmen/química , Análise do Sêmen/instrumentação , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/citologia
4.
JIMD Rep ; 34: 27-32, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27481510

RESUMO

The literature describes eight cases of mutations in the DPM1 gene generating DMP1-CDG, causing similar phenotype of early onset seizures, microcephaly and developmental delay. Investigations of these patients revealed associated abnormal findings on brain imaging, elevated CK, abnormal clotting factors and mildly deranged serum transaminases. We describe the ninth case of DMP1-CDG, whose clinical presentation includes severe gastrointestinal involvement, i.e. food protein induced enterocolitis syndrome (FPIES). Gastrointestinal manifestations (GIT) of the congenital glycosylation disorders have included deranged liver function, hepatomegaly, liver fibrosis, steatosis and protein-losing enteropathy. This is the first report of a congenital glycosylation disorder being associated with FPIES.

5.
Biomed Microdevices ; 18(4): 73, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27464497

RESUMO

The vascular endothelium and shear stress are critical determinants of physiological hemostasis and platelet function in vivo, yet current diagnostic and monitoring devices do not fully incorporate endothelial function under flow in their assessment and, therefore, they can be unreliable and inaccurate. It is challenging to include the endothelium in assays for clinical laboratories or point-of-care settings because living cell cultures are not sufficiently robust. Here, we describe a microfluidic device that is lined by a human endothelium that is chemically fixed, but still retains its ability to modulate hemostasis under continuous flow in vitro even after few days of storage. This device lined with a fixed endothelium supports formation of platelet-rich thrombi in the presence of physiological shear, similar to a living arterial vessel. We demonstrate the potential clinical value of this device by showing that thrombus formation and platelet function can be measured within minutes using a small volume (0.5 mL) of whole blood taken from subjects receiving antiplatelet medications. The inclusion of a fixed endothelial microvessel will lead to biomimetic analytical devices that can potentially be used for diagnostics and point-of-care applications.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Dispositivos Lab-On-A-Chip , Trombose/diagnóstico , Plaquetas/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Fibrina/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Inibidores da Agregação Plaquetária/farmacologia , Sistemas Automatizados de Assistência Junto ao Leito , Estresse Mecânico , Trombose/sangue , Trombose/tratamento farmacológico
6.
Reproduction ; 151(6): 657-71, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27002000

RESUMO

Syncytial nuclear aggregates (SNAs), clusters of nuclei in the syncytiotrophoblast of the human placenta, are increased as gestation advances and in pregnancy pathologies. The origins of increased SNAs are unclear; however, a better appreciation of the mechanism may give insight into placental ageing and factors underpinning dysfunction. We developed three models to investigate whether SNA formation results from a dynamic process of nuclear movement and to generate alternative hypotheses. SNA count and size were measured in placental explants cultured over 16 days and particles released into culture medium were quantified. Primary trophoblasts were cultured for 6 days. Explants and trophoblasts were cultured with and without cytoskeletal inhibitors. An in silico model was developed to examine the effects of modulating nuclear behaviour on clustering. In explants, neither median SNA number (108 SNA/mm(2) villous area) nor size (283 µm(2)) changed over time. Subcellular particles from conditioned culture medium showed a wide range of sizes that overlapped with those of SNAs. Nuclei in primary trophoblasts did not change position relative to other nuclei; apparent movement was associated with positional changes of the syncytial cell membrane. In both models, SNAs and nuclear clusters were stable despite pharmacological disruption of cytoskeletal activity. In silico, increased nuclear movement, adhesiveness and sites of cytotrophoblast fusion were related to nuclear clustering. The prominence of SNAs in pregnancy disorders may not result from an active process involving cytoskeleton-mediated rearrangement of syncytial nuclei. Further insights into the mechanism(s) of SNA formation will aid understanding of their increased presence in pregnancy pathologies.


Assuntos
Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Citoesqueleto/ultraestrutura , Placenta/ultraestrutura , Trofoblastos/ultraestrutura , Feminino , Imunofluorescência , Humanos , Gravidez , Imagem com Lapso de Tempo
7.
JIMD Rep ; 26: 91-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26303608

RESUMO

Pyridox(am)ine 5'-phosphate oxidase deficiency results in an early-onset neonatal encephalopathy that can be fatal if not detected and treated early. The condition is rare, can result in preterm delivery, and can mimic hypoxic ischemic encephalopathy. Thus, suspicion of the diagnosis, appropriate investigations, and therapeutic trials with pyridoxal-5'-phosphate are often delayed. In this paper we report four cases of pyridox(am)ine 5'-phosphate oxidase deficiency, two of whom are siblings. Three were treated with pyridoxal-5'-phosphate in the first few days of life and the fourth within the first month. One of the siblings was electively treated from birth until a diagnosis was secured. Our cases demonstrate that early diagnosis and treatment can be associated with normal neurodevelopment in childhood. We suggest that a low threshold for investigating for pyridox(am)ine 5'-phosphate oxidase deficiency and electively treating with pyridoxal-5'-phosphate is considered in any neonate with encephalopathy, including those with presumed hypoxic ischemic encephalopathy in whom the degree of encephalopathy is not expected from perinatal history, cord gases and/or neuroimaging.

8.
Toxicol Pathol ; 42(4): 672-83, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24499802

RESUMO

Pharmacologically, vasoactive agents targeting endothelial and/or smooth muscle cells (SMC) are known to cause acute drug-induced vascular injury (DIVI) and the resulting pathology is due to endothelial cell (EC) perturbation, activation, and/or injury. Alteration in EC structure and/or function may be a critical event in vascular injury and, therefore, evaluation of the circulatory kinetic profile and secretory pattern of EC-specific proteins such as VWF and VWFpp could serve as acute vascular injury biomarkers. In rat and dog models of DIVI, this profile was determined using pharmacologically diverse agents associated with functional stimulation/perturbation (DDAVP), pathological activation (lipopolysaccharide [LPS]/endotoxin), and structural damage (fenoldopam [FD], dopamine [DA], and potassium channel opener (PCO) ZD6169). In rats, FD caused moderate DIVI and time-related increase in plasma VWF levels ∼33% while in control rats VWF increased ∼5%. In dogs, VWF levels transiently increased ∼30% when there was morphologic evidence of DIVI by DA or ZD6169. However, in dogs, VWFpp increased >60-fold (LPS) and >6-fold (DDAVP), respectively. This was in comparison to smaller dynamic 1.38-fold (LPS) and 0.54-fold (DDAVP) increases seen in plasma VWF. Furthermore, DA was associated with a dose-dependent increase in plasma VWFpp. In summary, VWF and VWFpp can discriminate between physiological and pathological perturbation, activation, and injury to ECs.


Assuntos
Células Endoteliais/patologia , Precursores de Proteínas/sangue , Lesões do Sistema Vascular/patologia , Administração Oral , Amidas/efeitos adversos , Animais , Benzofenonas/efeitos adversos , Biomarcadores/sangue , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cães , Dopamina/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Células Endoteliais/efeitos dos fármacos , Feminino , Fenoldopam/efeitos adversos , Masculino , Flebotomia , Ratos , Ratos Wistar , Lesões do Sistema Vascular/etiologia , Fator de von Willebrand
9.
Placenta ; 34(12): 1251-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24172869

RESUMO

Syncytial nuclear aggregates (SNAs) are increased in pregnancy complications and include 'true' syncytial knots and inter-villous bridges. Apparent nuclear overlay caused by sectioning artefacts are frequently counted from single sections. Haematoxylin and eosin stained serial sections were assessed for frequency of SNA subtypes in placentas from normal, preeclamptic and fetal growth restricted (FGR) pregnancies. There were more sectioning artefacts and syncytial knots and fewer bridges in samples from preeclampsia compared to controls. There were no significant differences between FGR and control samples. This suggests the villous tree in preeclampsia has less inherent structural support and trophoblast cell dynamics are different.


Assuntos
Artefatos , Núcleo Celular/patologia , Vilosidades Coriônicas/patologia , Microtomia , Pré-Eclâmpsia/patologia , Trofoblastos/patologia , Adulto , Forma do Núcleo Celular , Cesárea , Feminino , Retardo do Crescimento Fetal/patologia , Humanos , Placentação , Gravidez , Adulto Jovem
10.
Toxicol Pathol ; 40(6): 874-86, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22549976

RESUMO

Fenoldopam, a dopaminergic DA1 agonist, induces vasodilatation via nitric oxide (NO), and this may be associated with mesenteric arterial injury. NO is produced from the enzymatic action of nitric oxide synthase (NOS), which is regulated by the shear-stress mediating protein caveolin-1. Profound vasodilatation and accompanied decreased shear are early events that could initiate vascular injury. Therefore, it is of interest to determine the role of caveolin-1 and the NO pathway in fenoldopam-induced vascular injury. At sites of fenoldopam-induced mesenteric arterial injury, decreased caveolin-1 expression and apoptosis were prominent immunohistochemical findings. An additional finding at these sites of injury were loss and/or reduced expression of caveolin-1 regulated structural proteins, connexin-43, (gap junction) ZO-1, and claudin (tight junctions). Because functional loss of caveolin-1 is associated with increased NOS activity and vasodilatation via NO, studies were conducted to show a NO donor produced vascular lesions in the mesenteric arteries morphologically similar to those induced by fenoldopam. Moreover, the incidence and severity of fenoldopam-induced vascular injury were reduced when an NOS inhibitor or a scavenger of NO-generated free radicals were coadministered with fenoldopam. Collectively, these data suggest that caveolin-1 and its regulated NO pathway may play an important role in vasodilatory drug-induced vascular injury.


Assuntos
Fenoldopam/toxicidade , Óxido Nítrico/metabolismo , Lesões do Sistema Vascular/induzido quimicamente , Lesões do Sistema Vascular/metabolismo , Análise de Variância , Animais , Caspase 3/metabolismo , Caveolina 1/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/patologia , Doadores de Óxido Nítrico/toxicidade , Nitroprussiato/toxicidade , Ácido Peroxinitroso/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Lesões do Sistema Vascular/patologia
11.
Arch Dis Child ; 94(10): 790-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19556220

RESUMO

BACKGROUND: Cerebral venous sinus thrombosis (CVST) in children is associated with a high incidence of serious morbidity and mortality. The presenting features are variable. It can be diagnostically challenging and the optimal treatment is uncertain. AIM: To describe the features of a series of children with CVST treated in a single paediatric neurology centre and to discuss the role of local thrombolysis. METHODS: Electronic databases were searched using diagnostic labels and International Classification of Diseases (ICD) codes to identify children aged 1 month to under 17 years with CVST. Their records were reviewed. RESULTS: 21 children were identified over a period of 8.25 years with a median age of 7.1 years. The presenting symptoms included headache (15 children), vomiting (14 children) and visual disturbance (eight children). Signs found included papilloedema (16 children), fever (six children) and sixth nerve palsy (six children). The most common underlying condition was middle ear infection (13 children). All cases received unfractionated heparin and four severe cases received local pharmacological thrombolysis. 48% of cases had an adverse outcome (death, chronic intracranial hypertension, residual hemiparesis or sixth nerve palsy). DISCUSSION: CVST has non-specific presenting features and a high risk of significant morbidity. CVST is typically found in association with a predisposing condition. Although heparin is the mainstay of treatment, thrombolysis may reverse deterioration as seen in three cases in this series. However, there is insufficient evidence to recommend the routine use of thrombolysis at present.


Assuntos
Trombose dos Seios Intracranianos/diagnóstico , Trombose dos Seios Intracranianos/tratamento farmacológico , Terapia Trombolítica/métodos , Adolescente , Anticoagulantes/uso terapêutico , Criança , Pré-Escolar , Feminino , Fibrinolíticos/uso terapêutico , Seguimentos , Transtornos da Cefaleia Secundários/etiologia , Heparina/uso terapêutico , Humanos , Lactente , Masculino , Fatores de Risco , Trombose dos Seios Intracranianos/complicações , Trombofilia/complicações , Trombofilia/diagnóstico , Fatores de Tempo , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento , Transtornos da Visão/etiologia , Vômito/etiologia
12.
Emerg Med J ; 24(7): 482-4, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17582039

RESUMO

Management of paracetamol overdose (POD) is common in the emergency department (ED) and forms part of the clinical effectiveness audit programme of the British Association for Emergency Medicine. N-acetylcysteine (NAC) infusion regimens for the treatment of POD are complicated and prescribing and administration errors have been well documented. This study assessed the ability of doctors and nurses to calculate correct doses using manual calculation skills and a weight-based NAC dosing chart when prescribing and preparing NAC infusions. With manual calculations, errors were made by doctors and nurses in 26% of cases collectively. No errors were made using the dosing chart. The dosing chart ensured 100% accuracy in dose calculations, which may translate into improved patient safety.


Assuntos
Acetaminofen/intoxicação , Acetilcisteína/administração & dosagem , Analgésicos não Narcóticos/intoxicação , Expectorantes/administração & dosagem , Adulto , Competência Clínica , Esquema de Medicação , Overdose de Drogas , Emergências , Humanos , Infusões Parenterais , Corpo Clínico Hospitalar , Erros de Medicação/prevenção & controle , Recursos Humanos de Enfermagem Hospitalar
13.
Arch Dis Child Fetal Neonatal Ed ; 91(5): F320-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16690640

RESUMO

BACKGROUND: The long term outcome of children entered into neonatal trials of high frequency oscillatory ventilation (HFOV) or conventional ventilation (CV) has been rarely studied. OBJECTIVE: To evaluate respiratory and neurodevelopmental outcomes for children entered into the United Kingdom Oscillation Study, which was designed to evaluate these outcomes. METHODS: Surviving infants were followed until 2 years of age corrected for prematurity. Study forms were completed by local paediatricians at routine assessments, and parents were asked to complete a validated neurodevelopmental questionnaire. RESULTS: Paediatricians' forms were returned for 73% of the 585 surviving infants. Respiratory symptoms were common in all infants, and 41% had received inhaled medication. Mode of ventilation had no effect on frequency of any symptoms. At 24 months of age, severe neurodevelopmental disability was present in 9% and other disabilities in 38% of children, but the prevalence of disability was similar in children who received HFOV or CV (relative risk 0.93; 95% confidence interval 0.74 to 1.16). The prevalence of disability did not vary by gestational age, but boys were more likely to have overall disability. Developmental scores were unaffected by mode of ventilation (relative risk 1.13; 95% confidence interval 0.78 to 1.63) and were lower in infants born before 26 weeks gestation compared with babies born at 26-28 weeks. CONCLUSIONS: Initial mode of ventilation in very preterm infants has no impact on respiratory or neurodevelopmental morbidity at 2 years. HFOV and CV appear equally effective for the early treatment of respiratory distress syndrome.


Assuntos
Ventilação de Alta Frequência , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Desenvolvimento Infantil , Deficiências do Desenvolvimento/etiologia , Seguimentos , Crescimento , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Terapia Intensiva Neonatal/métodos , Readmissão do Paciente/estatística & dados numéricos , Transtornos Respiratórios/etiologia , Respiração Artificial/métodos , Resultado do Tratamento
14.
Arch Dis Child Fetal Neonatal Ed ; 91(3): F197-201, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16418306

RESUMO

OBJECTIVE: To test the hypothesis that male compared with female prematurely born infants would have worse lung function at follow up. DESIGN: Prospective follow up study. SETTING: Tertiary neonatal intensive care units PATIENTS: Seventy six infants, mean (SD) gestational age 26.4 (1.5) weeks, from the United Kingdom oscillation study. INTERVENTIONS: Lung function measurements at a corrected age of 1 year. MAIN OUTCOME MEASURES: Airways resistance (Raw) and functional residual capacity (FRC(pleth)) measured by whole body plethysmography, specific conductance (sGaw) calculated from Raw and FRC(pleth), and FRC measured by a helium gas dilution technique (FRC(He)). RESULTS: The 42 male infants differed significantly from the 34 female infants in having a lower birth weight for gestation, requiring more days of ventilation, and a greater proportion being oxygen dependent at 36 weeks postmenstrual age and discharge. Furthermore, mean Raw and FRC(pleth) were significantly higher and mean sGaw significantly lower. After adjustment for birth and current size differences, the sex differences in FRC(pleth) and sGaw were 15% and 26% respectively and remained significant. CONCLUSION: Lung function at follow up of prematurely born infants is influenced by sex.


Assuntos
Doenças do Prematuro/fisiopatologia , Transtornos Respiratórios/fisiopatologia , Caracteres Sexuais , Resistência das Vias Respiratórias/fisiologia , Feminino , Seguimentos , Capacidade Residual Funcional , Humanos , Recém-Nascido , Pneumopatias Obstrutivas/fisiopatologia , Masculino , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Sensibilidade e Especificidade
15.
Arch Dis Child Fetal Neonatal Ed ; 91(3): F193-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16239293

RESUMO

BACKGROUND: Airways obstruction in premature infants is often assessed by plethysmography, which requires sedation. The interrupter (Rint) technique does not require sedation, but has rarely been examined in children under 2 years of age. OBJECTIVE: To compare Rint results with plethysmographic measurements of airway resistance (Raw) in prematurely born, young children. DESIGN: Prospective study. SETTING: Infant and Paediatric Lung Function Laboratories. PATIENTS: Thirty children with a median gestational age of 25-29 weeks and median postnatal age of 13 months. INTERVENTIONS AND MAIN OUTCOME MEASURES: The infants were sedated, airway resistance was measured by total body plethysmography (Raw), and Rint measurements were made using a MicroRint device. Further Raw and Rint measurements were made after salbutamol administration if the children remained asleep. RESULTS: Baseline measurements of Raw and Rint were obtained from 30 and 26 respectively of the children. Mean baseline Rint values were higher than mean baseline Raw results (3.45 v 2.84 kPa/l/s, p = 0.006). Limits of agreement for the mean difference between Rint and Raw were -1.52 to 2.74 kPa/l/s. Ten infants received salbutamol, after which the mean Rint result was 3.6 kPa/l/s and mean Raw was 3.1 kPa/l/s (limits of agreement -0.28 to 1.44 kPa/l/s). CONCLUSION: The poor agreement between Rint and Raw results suggests that Rint measurements cannot substitute for plethysmographic measurements in sedated prematurely born infants.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Resistência das Vias Respiratórias/fisiologia , Doenças do Prematuro/diagnóstico , Pletismografia Total/métodos , Albuterol , Broncodilatadores , Capacidade Residual Funcional/fisiologia , Humanos , Lactente , Recém-Nascido , Pletismografia Total/normas , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Arch Dis Child Fetal Neonatal Ed ; 90(4): F320-3, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15878935

RESUMO

OBJECTIVES: To determine the occurrence of respiratory morbidity during infancy after very premature birth and to identify risk factors. DESIGN: Prospective follow up study. SETTING: The United Kingdom oscillation study. PATIENTS: 492 infants, all born before 29 weeks gestation. INTERVENTIONS: Structured questionnaires were completed by local paediatricians when the infants were seen in outpatients at 6 and 12 months of age corrected for prematurity. MAIN OUTCOME MEASURES: Cough, wheeze, and treatment requirements and the composite measure of respiratory morbidity (cough, frequent cough, cough without infection, wheeze, frequent wheeze, wheeze without infection, and use of chest medicine) and their relation to 13 possible explanatory variables. RESULTS: At 6 and 12 months of corrected age, 27% of the infants coughed and 6% had frequent (more than once a week) cough, and 20% and 3% respectively had wheeze or frequent wheeze. At 6 and 12 months, 14% of infants had taken bronchodilators and 8% inhaled steroids. After adjustment for multiple outcome testing, four factors were associated with increased respiratory morbidity: male sex, oxygen dependency at 36 weeks postmenstrual age, having older siblings aged less than 5 years, and living in rented accommodation. CONCLUSIONS: Male infants are particularly vulnerable to respiratory morbidity in infancy after very premature birth. It is important to identify a safe and effective strategy to prevent chronic oxygen dependency.


Assuntos
Doenças do Prematuro/etiologia , Recém-Nascido Prematuro , Nascimento Prematuro , Transtornos Respiratórios/etiologia , Broncodilatadores/administração & dosagem , Tosse/etiologia , Métodos Epidemiológicos , Feminino , Humanos , Lactente , Recém-Nascido , Doenças do Prematuro/tratamento farmacológico , Masculino , Oxigenoterapia , Gravidez , Transtornos Respiratórios/tratamento farmacológico , Sons Respiratórios/etiologia , Fatores Sexuais
18.
Theriogenology ; 63(4): 1092-110, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15710196

RESUMO

Lamb survival is impaired in low birth weight lambs, and those that are slow to stand and suck. Many of the factors that influence lamb vigour, such as parity, litter size, and breed, may exert their effects, at least partially, before birth by influencing placenta development. Our hypothesis was that retarded lamb behavioural development was due to differences in placentation in these animals. Data were collected from Blackface and Suffolk lambs in the first 2 h after birth and placentas were collected when delivered. Suffolk lambs, which were behaviourally slower and had lower rectal temperatures than Blackface lambs, were associated with larger but less efficient placentas (placental efficiency defined as foetal weight supported per g placenta) with fewer foetal cotyledons than Blackface placentas. Triplet lambs were significantly slower than twin or single lambs to suck and had lower rectal temperatures. Although placenta efficiency increased with litter size, placenta and cotyledon weight, and cotyledon number increased with twinning but not thereafter. It seemed likely that triplet lambs suffered some placental insufficiency in comparison to other litter sizes. Lambs born to first parity mothers were slower to stand and reach the udder than lambs of more experienced ewes, and first parity ewes also had smaller and less efficient placentas although cotyledon number was not affected. Male lambs tended to be slower than female lambs for most behaviours, although rectal temperatures were not affected. The sire of the lamb also influenced lamb behaviour and rectal temperature. Both lamb sex and lamb sire influenced the average weight of placental cotyledons, thus some of the sire effect on the behaviour and birth weight of his progeny might be mediated through placental development. Lamb neonatal vigour was correlated with placental efficiency suggesting that lamb behaviour immediately after birth is related to placental development and function.


Assuntos
Animais Recém-Nascidos/fisiologia , Comportamento Animal/fisiologia , Paridade , Placenta/anatomia & histologia , Ovinos/fisiologia , Animais , Peso ao Nascer , Regulação da Temperatura Corporal , Cruzamento , Feminino , Tamanho da Ninhada de Vivíparos , Masculino , Tamanho do Órgão , Gravidez , Ovinos/genética , Especificidade da Espécie
19.
J Clin Invest ; 114(10): 1457-66, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545996

RESUMO

Hemoglobin (Hb) A production during red blood cell development is coordinated to minimize the deleterious effects of free alpha- and beta-Hb subunits, which are unstable and cytotoxic. The alpha-Hb-stabilizing protein (AHSP) is an erythroid protein that specifically binds alpha-Hb and prevents its precipitation in vitro, which suggests that it may function to limit free alpha-Hb toxicities in vivo. We investigated this possibility through gene ablation and biochemical studies. AHSP(-/-) erythrocytes contained hemoglobin precipitates and were short-lived. In hematopoietic tissues, erythroid precursors were elevated in number but exhibited increased apoptosis. Consistent with unstable alpha-Hb, AHSP(-/-) erythrocytes contained increased ROS and evidence of oxidative damage. Moreover, purified recombinant AHSP inhibited ROS production by alpha-Hb in solution. Finally, loss of AHSP worsened the phenotype of beta-thalassemia, a common inherited anemia characterized by excess free alpha-Hb. Together, the data support a model in which AHSP binds alpha-Hb transiently to stabilize its conformation and render it biochemically inert prior to Hb A assembly. This function is essential for normal erythropoiesis and, to a greater extent, in beta-thalassemia. Our findings raise the possibility that altered AHSP expression levels could modulate the severity of beta-thalassemia in humans.


Assuntos
Eritrócitos/metabolismo , Eritropoese , Hemoglobinas/química , Hemoglobinas/fisiologia , Talassemia beta/metabolismo , Animais , Apoptose , Eritrócitos/patologia , Corpos de Heinz/química , Corpos de Heinz/metabolismo , Hemoglobinas/genética , Heterozigoto , Cinética , Camundongos , Camundongos Knockout , Modelos Biológicos , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
20.
Arch Dis Child Fetal Neonatal Ed ; 88(4): F329-32, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12819168

RESUMO

OBJECTIVE: To determine if chest radiograph appearance at 28 days or 36 weeks postmenstrual age (PMA) can predict recurrent wheeze or cough at follow up in prematurely born infants more effectively than readily available clinical data. DESIGN: Chest radiographs of infants entered into the UKOS trial, who had had a chest radiograph at 28 days and 36 weeks PMA and completed six months of follow up, were assessed for the presence of fibrosis, interstitial shadows, cystic elements, and hyperinflation. At 6 months of corrected age, the occurrence and frequency of wheeze and cough since discharge were determined using a symptom questionnaire. PATIENTS: A total of 185 infants with a median gestational age of 26 (range 23-28) weeks. RESULTS: Thirty seven infants wheezed more than once a week, compared with the rest of the cohort. These infants had significantly higher chest radiograph scores at 28 days (p = 0.020) and 36 weeks PMA (p = 0.005), with significantly higher scores at 28 days for fibrosis (p = 0.017) and at 36 weeks PMA for fibrosis (p = 0.001) and cystic elements (p = 0.0007). They had also been ventilated for longer (p = 0.013). Forty four infants coughed more than once a week; they did not differ significantly from the rest of the cohort. An abnormal chest radiograph score at 36 weeks PMA had the largest area under the receiver operator characteristic curve with regard to prediction of frequent wheeze. CONCLUSION: An abnormal chest radiograph appearance at 36 weeks PMA predicts frequent wheeze at follow up and appears to be a better predictor than readily available clinical data.


Assuntos
Doenças do Prematuro/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Sons Respiratórios/diagnóstico , Fatores Etários , Tosse , Seguimentos , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Valor Preditivo dos Testes , Fibrose Pulmonar/diagnóstico por imagem , Curva ROC , Radiografia , Respiração Artificial , Fatores de Risco
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