RESUMO
A recent trial showed that high-dose docosahexaenoic acid (high-DHA) supplementation of infants born <29 weeks' gestation improves intelligence quotient (IQ) at five years' corrected age. However, this finding has not been detected by other trials of DHA, which either did not measure IQ or included more mature infants. We analyzed the subgroup of 204 infants born <29 weeks' from our earlier randomized trial of high-DHA (â¼1 % total fatty acids) or standard-DHA (â¼ 0.3 % total fatty acids). Participants were assessed for cognition at 18 months, and IQ and behavior at seven years' corrected age. No group differences were detected for mean cognitive, IQ or behavior scores. At 18 months, 18.8 % of children in the high-DHA group had a cognitive score <85, compared with 31.1 % of children in the standard-DHA group, but at seven years there was no difference. Although an underpowered post-hoc subgroup analysis, this study provides limited support to recommendations that infants born <29 weeks' gestation require supplemental DHA.
Assuntos
Ácidos Docosa-Hexaenoicos , Recém-Nascido Prematuro , Recém-Nascido , Lactente , Criança , Feminino , Humanos , Suplementos Nutricionais , Cognição , Ácidos GraxosRESUMO
OBJECTIVE: To investigate whether use of ST analysis of the fetal electrocardiogram (STan) as an adjunct to continuous cardiotocography (CTG) reduces the rate of emergency Cesarean section (EmCS) compared with CTG alone. METHODS: This was a randomized controlled trial of patients with a singleton fetus in cephalic presentation at ≥ 36 weeks' gestation, requiring continuous electronic fetal monitoring during labor at a tertiary maternity hospital in Adelaide, Australia, between January 2018 and July 2021. Participants were randomized to undergo CTG + STan or CTG alone. The calculated sample size was 1818 participants. The primary outcome was EmCS. Secondary outcomes included metabolic acidosis, a composite adverse perinatal outcome, and other maternal and neonatal morbidity and safety outcomes. RESULTS: The present study enrolled 970 women, of whom 967 were included in the primary analysis. EmCS occurred in 107/482 (22.2%) deliveries in the CTG + STan arm and in 107/485 (22.1%) in the CTG arm (adjusted relative risk, 1.02 (95% CI, 0.81-1.27); P = 0.89). There was no difference in the rate of adverse maternal or neonatal outcomes between arms. CONCLUSIONS: The addition of STan as an adjunct to continuous CTG did not reduce the EmCS rate. The smaller-than-anticipated sample size meant that this study was underpowered to detect absolute differences of ≤ 5% and, therefore, this negative finding could be due to a Type-2 error. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Assuntos
Cardiotocografia , Trabalho de Parto , Recém-Nascido , Gravidez , Feminino , Humanos , Cesárea , Austrália , Parto , Eletrocardiografia , Monitorização FetalRESUMO
The number of children with Autism Spectrum Disorder (ASD) has significantly increased over the last few years. On the one hand, this surge may be associated with increased awareness of this entity and the greater availability of diagnostic tools. On the other hand, influence of factors believed to cause or facilitate ASD development (including environment pollution, stress of modern civilization, brain trauma and use of drugs) could have a negative impact on individuals in the phase of their social and psychological development. Due to the increasing problem, more and more attention is being focused on early detection of ASD, what allows to intervene at the earliest time point. In consequence, the quality of life of ASD-affected people may be significantly improved if diagnosed early. In this review, the list of possible risk factors for ASD is critically appraised and some "pearls for practice", helping in early diagnosis of even mild ASD are outlined.
Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/psicologia , Encéfalo , Criança , Humanos , Qualidade de Vida , Fatores de RiscoRESUMO
INTRODUCTION: Monitoring for adverse events following immunisation (AEFI) is critical for vaccine pharmacovigilance. Given the global and expanding availability of mobile phones their utility for consumer-based vaccine safety surveillance is of interest but little is known about consumer acceptability. This study nested within the Stimulated Telephone Assisted Rapid Safety Surveillance (STARSS) randomised control trial sought to evaluate the acceptability of SMS for AEFI surveillance. METHODS: The primary STARSS study was a multi-centre RCT evaluating the efficacy of repeated SMS prompts for AEFI surveillance with participants being adult vaccinees or parents of children receiving any vaccine. This nested study enrolled primary RCT participants who completed a detailed computer assisted telephone interview to determine their attitudes towards SMS-based surveillance and ascertain their knowledge and attitudes toward vaccine safety, efficacy, data privacy and use of electronic health records. Attitudes to surveillance and related behaviour were used as measures of acceptability. RESULTS: 20% (1200/6555) of the participants were enrolled and 1139 completed the full-length questionnaire. 96% indicated that SMS-based surveillance after immunisation to check the safety of the vaccine "should be done" but 62% of all respondents said it should be done but consent should be sought first. Neither vaccine safety attitudes nor attitudes toward privacy were associated with opposition to SMS-based surveillance. In terms of SMS related behaviour demographic rather than attitudinal factors were associated with non-compliance. CONCLUSION: Overall, the attitude towards SMS-based surveillance was very favourable. Experiencing the SMS surveillance has the effect of reducing opposition to an SMS surveillance system, and at the same time increasing the likelihood of a preference for prior consent. Detection of a vaccine safety signal could be impeded in particular demographic groups who are non-compliant and we should undertake further research to understand why these groups are non-compliant and how this can be improved.
Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Telemedicina , Adulto , Criança , Humanos , Imunização , Telefone , VacinaçãoRESUMO
BACKGROUND: There is insufficient information on the prevalence of hypertension (HPT) among children and adolescents with ID. AIM: The aim of this study was to determine the prevalence of HPT in children and adolescents with ID in comparison with the control group, which accounted for children and adolescents without ID. METHODS: The study included 568 students with ID, aged from 7 to 18, attending special education institutions in southeastern Poland. The control group consisted of 568 students (matched to the study group for age and gender) without ID, attending randomly selected elementary and secondary schools located in the same area. Blood pressure was measured in compliance with the European Society of Hypertension recommendations. RESULTS: The overall prevalence of HPT and pre-HPT in children and adolescents with ID were 18.5 and 20.6% respectively. Prevalence of HPT and pre-HPT in children and adolescents without ID were 5.8 and 18.5% respectively. Children and adolescents with a higher level of ID were found to be at a greater risk of HPT. An excessive body mass and older age were predisposing factors to a significantly higher prevalence of HPT in children and adolescents with ID. CONCLUSION: The prevalence of HPT among students with ID was more than three times higher than in the general population. The level of ID, age, sex and body mass significantly correlated with HPT in the study group.
Assuntos
Hipertensão/epidemiologia , Deficiência Intelectual/epidemiologia , Pré-Hipertensão/epidemiologia , Adolescente , Criança , Comorbidade , Feminino , Humanos , Masculino , Polônia/epidemiologia , PrevalênciaRESUMO
A cornea bank must have an organizational structure in which responsibility and authority to issue directives are clearly defined. It must also use a documented quality management system on the basis of good practice procedures which is maintained to the current standards. The personnel of a cornea bank must be present in sufficient numbers and be suitably qualified. A cornea bank must be in possession of appropriate facilities which are suitable for the main purpose of conservation of donor corneas. All equipment must be designed and maintained corresponding to the intended purpose. Deviations from the stipulated quality and safety standards must give rise to documented investigations which include decisions on options for correctional and preventive measures. Acquisition of donors and tissue sampling must be strictly controlled and documented. This also applies to entry of donor tissue in the cornea bank. During conservation a microscopic examination of the endothelial cell layer must be carried out at least once. Measures must be taken to keep the risk of contamination as low as possible. Donor corneal tissue can only be released if defined criteria are fulfilled. Any suspicion of severe undesired reactions and events for the recipient of a corneal transplant must be registered with the authorities. The activities of a cornea bank must maintain and adapt the state-of-the-art with respect to scientific progress.
Assuntos
Córnea , Transplante de Córnea/normas , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Bancos de Tecidos/normas , AlemanhaRESUMO
Organotypic cornea equivalents are used as in vitro models for permeation studies. Many ophthalmic drugs are applied as ester prodrugs to achieve a higher bioavailability. The esterase activity of three corneal human cell lines (epithelial, stromal, endothelial cells) as well as of excised porcine cornea, human donor cornea and human cornea construct (HCC) was investigated and compared. Esterase activity was determined using p-nitrophenyl acetate and hydrocortisone acetate (HCA) as esterase substrates. Hydrocortisone acetate permeation across porcine cornea, human donor cornea and HCC was studied in vitro using Franz-diffusion cells. Corneal epithelial cells showed the highest esterase activity and only small differences to keratocytes and endothelial cells were detectable. The permeation barrier properties of the different corneal tissues were very similar in the case of HCA permeation whereas HCA metabolism rates were in the ranking order of porcine cornea > HCC > human donor cornea. Permeation and metabolism studies indicate that the in vitro permeation model HCC is able to adequately convert hydrocortisone acetate to hydrocortisone.
Assuntos
Córnea/metabolismo , Esterases/metabolismo , Soluções Oftálmicas/farmacocinética , Idoso , Animais , Disponibilidade Biológica , Células Cultivadas , Córnea/citologia , Córnea/efeitos dos fármacos , Córnea/enzimologia , Substância Própria/efeitos dos fármacos , Substância Própria/enzimologia , Substância Própria/metabolismo , Endotélio Corneano/citologia , Endotélio Corneano/efeitos dos fármacos , Endotélio Corneano/metabolismo , Epitélio Corneano/citologia , Epitélio Corneano/efeitos dos fármacos , Epitélio Corneano/enzimologia , Epitélio Corneano/metabolismo , Humanos , Hidrocortisona/análogos & derivados , Hidrocortisona/metabolismo , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Permeabilidade , Pró-Fármacos/farmacocinética , Suínos , Fatores de Tempo , Doadores de TecidosRESUMO
AIMS: For the study of transcorneal in vitro permeation of ophthalmic drugs, excised animal cornea or corneal epithelial cell culture are frequently used as a replacement for the human cornea. The main purposes of this study were to reconstruct a complete human organotypic cornea equivalent, consisting of all three different cell types (epithelial, stromal, and endothelial); to test the barrier function of this bio-engineered human cornea using three different model drugs (pilocarpine hydrochloride (PHCl), befunolol hydrochloride (BHCl), and hydrocortisone (HC)); and to determine its usefulness as an in vitro model for prediction of ocular drug absorption into the human eye. METHODS: A multilayer tissue construct was created step by step in Transwell cell culture insert using SV-40 immortalised human endothelial and epithelial cells and native stromal cells (fibroblasts). Morphology was characterised by light microscopy using routine H&E staining. Scanning electron microscopy was used to evaluate ultrastructural features. Ocular permeation of drugs across the human cornea construct was tested using modified Franz cells and compared with data obtained from excised porcine cornea and previously described porcine cornea constructs. RESULTS: and conclusion: The cornea construct exhibited typical corneal structures such as a monolayer of hexagonally shaped endothelial cells and a multilayered epithelium consisting of seven to nine cell layers with flat superficial cells. The formation of microplicae and microvilli was also confirmed. The human cornea construct showed similar permeation behaviour for all substances compared with excised porcine cornea. However, permeability (permeation coefficients K(p)) of the human cornea equivalent (PHCl 13.4*10(-6) (SD 3.01*10(-6)); BHCl 9.88*10(-6) (SD 1.79*10(-6)); HC 5.41*10(-6) (SD 0.40*10(-6)) cm/s) was about 1.6-1.8 fold higher than excised porcine cornea. Compared with data from the porcine cornea construct the cultivated human equivalent showed a decreased permeability. The reconstructed human cornea could be appropriate to predict drug absorption into the human eye.
Assuntos
Córnea/metabolismo , Soluções Oftálmicas/farmacocinética , Engenharia Tecidual , Antagonistas Adrenérgicos beta/farmacocinética , Córnea/efeitos dos fármacos , Humanos , Hidrocortisona/farmacocinética , Microscopia Eletrônica de Varredura , Mióticos/farmacocinética , Permeabilidade , Pilocarpina/farmacocinética , Propanolaminas/farmacocinéticaRESUMO
BACKGROUND: Apoptosis very probably plays a key part in endothelial cell loss during corneal storage in organ culture as well as hypothermic storage. However, the mechanisms underlying endothelial apoptosis are poorly understood. The response of a human corneal endothelial cell (HCEC) line to staurosporine, a known inducer of apoptosis, was investigated to gain insights into the intracellular modulators that participate in endothelial cell death. METHODS: Immortalised HCECs were studied after 3, 6, 12, and 24 hours of incubation with 0.2 micro M staurosporine. Cell shedding was monitored. Hoechst 33342 fluorescent DNA staining combined with propidium iodide was used for apoptosis/necrosis quantification and morphological examination. The caspase-3 active form was assessed using western blot, proteolytic activity detection, and immunocytochemistry. The cleaved form of poly(ADP-ribose) polymerase (PARP) was assessed using immunocytochemistry and western blot. The ultrastructural features of cells were screened after 12 hours with staurosporine or vehicle. RESULTS: The specific apoptotic nature of staurosporine induced HCEC death was confirmed. The ultrastructural features of staurosporine treated cells were typical of apoptosis. HCEC shedding and DNA condensation increased with time. Caspase-3 activity was detected as early as 3 hours after exposure with staurosporine, peaking at 12 hours of incubation. The presence of cleaved PARP after 3 hours confirmed caspase-3 activation. CONCLUSIONS: These data suggest strongly that HCEC cell death induced by staurosporine is apoptosis. The main consequence of HCEC apoptosis is shedding. Staurosporine induced apoptosis of endothelial cells involves activation of caspase-3, and could be a useful model to study strategies of cell death inhibition.
Assuntos
Apoptose/efeitos dos fármacos , Endotélio Corneano/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Estaurosporina/farmacologia , Western Blotting , Caspase 3 , Caspases/metabolismo , Linhagem Celular , Endotélio Corneano/enzimologia , Endotélio Corneano/fisiologia , Ativação Enzimática , Humanos , Imuno-Histoquímica/métodos , Microscopia Eletrônica , Poli(ADP-Ribose) Polimerases/metabolismoRESUMO
BACKGROUND: Removal of bovine serum from organ culture medium is necessary because of the variability in serum composition and the potential risk of infection. Two specific endothelial cell media (F99 and Endothelial-SFM) were compared with the routinely used medium MEM for their use in serum free cultivation of human corneal endothelial cells (HCEC) and donor corneas. METHODS: HCEC were incubated in three test media with or without increasing serum content and a growth assay was performed. Seven pairs of donor corneas were cultured in each of three media for 3 weeks, one cornea with serum supplementation and one without. Endothelial cell density was determined once each week. Trypan blue staining of the endothelium and vital staining of keratocytes was performed after 3 weeks. RESULTS: All three media promoted proliferation of cultured HCEC when supplemented with serum. Endothelial cell density of donor corneas was comparable after 3 weeks of cultivation in the different media. Only corneas cultured in medium MEM without serum exhibited a higher endothelial cell loss. Trypan blue staining of the endothelium after cultivation revealed the lowest number of damaged cells on corneas cultured in the medium Endothelial-SFM. The highest densities of keratocytes were found in corneas cultured in Endothelial-SFM and the lowest densities occurred after culture in MEM. CONCLUSION: After incubation in Endothelial-SFM even under serum free conditions corneas were found to be of higher quality with respect to endothelial cell survival, cell membrane integrity, and keratocyte density. This medium may replace MEM, which is routinely used in European eye banks but requires supplementation with serum.
Assuntos
Córnea/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , Idoso , Idoso de 80 Anos ou mais , Técnicas de Cultura de Células/métodos , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Córnea/citologia , Endotélio Corneano/citologia , Endotélio Corneano/efeitos dos fármacos , Humanos , Técnicas de Cultura de Órgãos/métodos , Preservação de Tecido/métodosRESUMO
PURPOSE: Endothelial cell loss can be observed after keratoplasty, therefore in a retrospective study we analysed whether there is a correlation between donor age, recipient age, time post-mortem, preoperative cell density, diagnosis of the recipient and postoperative endothelial cell density. METHODS: The endothelial cell densities of 120 patients who had undergone penetrating keratoplasty were examined over a period of 2 years. We divided the patients into four groups based on the endothelial cell density over 2 years. We examined the groups with regard to the parameters given above. RESULTS: The lowest postoperative cell densities 2 years after keratoplasty showed a high correlation with the highest donor and recipient age. Even the lowest preoperative cell density was found in this group. Patients who underwent keratoplasty because of keratoconus had the highest cell densities after 2 years and also the lowest donor and recipient age. The preoperative cell density was also highest in this group. DISCUSSION: The results indicate a correlation between increasing donor and recipient age, decreasing preoperative cell density and loss of endothelial cells 2 years after penetrating keratoplasty. Patients with the diagnosis keratoconus should also receive transplants with higher donor age.
Assuntos
Endotélio Corneano/patologia , Ceratoplastia Penetrante/patologia , Complicações Pós-Operatórias/patologia , Doadores de Tecidos , Adulto , Fatores Etários , Idoso , Contagem de Células , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
BACKGROUND: Echocardiographic contrast media have been used to assess myocardial perfusion and to enhance endocardial definition for improved assessment of left ventricular (LV) function. These methodologies, however, have been qualitative or have required extensive offline image analysis. Power modulation is a recently developed imaging technique that provides selective enhancement of microbubble-generated reflections. Our goal was to test the feasibility of using power modulation for combined quantitative assessment of myocardial perfusion and regional LV function in an animal model of acute ischemia. METHODS AND RESULTS: Coronary balloon occlusions were performed in 18 anesthetized pigs. Transthoracic power modulation images (Agilent 5500) were obtained during continuous intravenous infusion of the contrast agent Definity (DuPont) at baseline and during brief coronary occlusion and reperfusion and were analyzed with custom software. At each phase, myocardial perfusion was assessed by calculation, in 6 myocardial regions of interest, of mean pixel intensity and the rate of contrast replenishment after high-power ultrasound impulses. LV function was assessed by calculation of regional fractional area change from semiautomatically detected endocardial borders. All ischemic episodes caused detectable and reversible changes in perfusion and function. Perfusion defects, validated with fluorescent microspheres, were visualized in real time and confirmed by a significant decrease in pixel intensity in the left anterior descending coronary artery territory after balloon inflation and reduced rate of contrast replenishment. Fractional area change decreased significantly in ischemic segments and was restored with reperfusion. CONCLUSIONS: Power modulation allows simultaneous online assessment of myocardial perfusion and regional LV wall motion, which may improve the echocardiographic diagnosis of myocardial ischemia.
Assuntos
Circulação Coronária , Ecocardiografia/métodos , Processamento de Imagem Assistida por Computador , Isquemia Miocárdica/diagnóstico por imagem , Função Ventricular Esquerda , Animais , Oclusão com Balão , Meios de Contraste , Modelos Animais de Doenças , Ecocardiografia/instrumentação , Estudos de Viabilidade , Fluorocarbonos , Técnicas In Vitro , Masculino , Microesferas , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Suínos , Função Ventricular Esquerda/fisiologiaRESUMO
In vitro cultivation of human corneal endothelial cells (HCEC) is associated with loss of typical cobblestone-like appearance during successive passages. Thus far morphology was the sole criterion for the cell's endothelial nature. Mouse monoclonal antibodies (mabs) to human corneal endothelial cells were raised using standard immunization and hybridoma isolation procedures. The specificity of mabs for human corneal endothelial cells was tested in comparison to other endothelial cell types, to fibroblasts, corneal keratocytes and to human retinal pigmented epithelial cells. In addition immunofluorescence or immunoperoxidase staining was performed with frozen tissue sections of human corneas and with various other human tissues. The mab 9.3.E reacts with cultured human corneal endothelial cells, but not with cultured human fibroblasts and human keratocytes. In frozen sections selective positivity of corneal endothelium in contrast to negativity of the other corneal cell types was confirmed. In investigated extraocular tissues positivity was observed in smooth muscle cells including related cells (i.e. Ito and mesangial cells) and in Schwann's cells and adipocytes, but apparently not in vascular endothelial cells. The mab is human-specific and binds to a protein with a molecular weight of 130 kDa mainly accumulating along cell membranes. A mouse monoclonal antibody against human corneal endothelial cells was established in vitro and was shown to be capable of differentiating corneal endothelial cells from other corneal cell types, especially from corneal keratocytes. It is, however, not cornea-specific, but also reacts with certain extraocular cell types.
Assuntos
Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Endotélio Corneano/imunologia , Adipócitos/imunologia , Animais , Bovinos , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Feminino , Fibroblastos/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Secções Congeladas , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Epitélio Pigmentado Ocular/imunologia , Células de Schwann/imunologia , SuínosRESUMO
Genetically modified mice have created the need for accurate noninvasive left ventricular mass (LVM) measurements. Recent technical advances provide two-dimensional images adequate for LVM calculation using the area-length method, which in humans is more accurate than M-mode methods. We compared the standard M-mode and area-length methods in mice over a wide range of LV sizes and weights (62-210 mg). Ninety-one CD-1 mice (38 normal, 44 aortic banded, and 9 inherited dilated cardiomyopathy) were imaged transthoracically (15 MHz linear transducer, 120 Hz). Compared with necropsy weights, area-length measurements showed higher correlation than the M-mode method (r = 0.92 vs. 0.81), increased accuracy (bias +/- SD: 1.4 +/- 27.1% vs. 36.7 +/- 51.6%), and improved reproducibility. There was no significant difference between end-systolic and end-diastolic estimates. The truncated ellipsoid estimation produced results similar in accuracy to the area-length method. Whereas current echocardiographic technology can accurately and reproducibly estimate LVM with the two-dimensional, area-length formula in a variety of mouse models, additional technological improvements, rather than refinement of geometric models, will likely improve the accuracy of this methodology.
Assuntos
Ecocardiografia/normas , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/patologia , Miocárdio/patologia , Animais , Aorta , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/patologia , Doença Crônica , Modelos Animais de Doenças , Ecocardiografia/métodos , Ecocardiografia/estatística & dados numéricos , Feminino , Ventrículos do Coração/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Variações Dependentes do Observador , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: To assess the feasibility of measuring left atrial (LA) function with acoustic quantification (AQ) and then assess the effects of age and sex on LA reservoir, conduit, and booster pump function. PATIENTS AND SETTING: 165 subjects without cardiovascular disease, 3-79 years old, were enrolled by six tertiary hospital centres. INTERVENTIONS: Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line. MAIN OUTCOME MEASURES: Parameters of LA performance according to age and sex. RESULTS: Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function. CONCLUSIONS: LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.
Assuntos
Função do Átrio Esquerdo , Função Atrial , Ecocardiografia/métodos , Processamento de Sinais Assistido por Computador , Acústica , Adolescente , Adulto , Fatores Etários , Idoso , Envelhecimento/fisiologia , Algoritmos , Criança , Pré-Escolar , Eletrocardiografia , Estudos de Viabilidade , Feminino , Átrios do Coração/anatomia & histologia , Átrios do Coração/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais , Fatores SexuaisRESUMO
BACKGROUND: The success of long-term corneal organ culture is limited by the progressive loss of endothelial cells during culture and the use of culture medium supplemented with fetal calf serum as a possible source of contamination with infectious agents. In this study, we investigated the suitability of a serum-free medium (Endothelial-SFM) to improve preservation conditions for human donor corneas. METHODS: Six pairs of corneas were stored in Minimum Essential Medium (MEM) supplemented with 2% fetal calf serum (FCS) for 8-14 days. One cornea of each pair was then further cultivated in Endothelial-SFM supplemented with 2% FCS or in MEM with 2% FCS, respectively. In a second series of experiments, the endothelial cell density of seven pairs of freshly isolated donor corneas was determined during cultivation in Endothelial-SFM with 2% FCS or serum-free Endothelial-SFM. RESULTS: After precultivation in conventional medium, the endothelial cell density of corneas allocated to cultivation in Endothelial-SFM was 1000-1950 cells/mm2 and that of those subsequently cultured in MEM 1200-2000 cells/mm2. At 9 weeks, cell densities of 900-1500 cells/mm2 were found after cultivation in Endothelial-SFM compared with a total cell loss in MEM. Freshly isolated corneas cultured in Endothelial-SFM with or without FCS supplementation showed a decrease of endothelial cell density of about 20% within the first 2 weeks of storage. During further cultivation cell density remained constant without statistically significant differences between the groups. Glucose consumption of the corneas was higher in Endothelial-SFM than in MEM. Corneas stored in Endothelial-SFM with 2% FCS showed a higher glucose consumption than those preserved in serum-free Endothelial-SFM. CONCLUSION: Organ culture of human donor corneas using the serum-free basal medium Endothelial-SFM is superior to conventional culture conditions because the decrease in endothelial cell density can be ameliorated, the culture period can be prolonged and the risk of transmitting infectious agents via serum can be minimised.