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1.
medRxiv ; 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38585825

ABSTRACT

Collagen VI-related dystrophies (COL6-RDs) manifest with a spectrum of clinical phenotypes, ranging from Ullrich congenital muscular dystrophy (UCMD), presenting with prominent congenital symptoms and characterised by progressive muscle weakness, joint contractures and respiratory insufficiency, to Bethlem muscular dystrophy, with milder symptoms typically recognised later and at times resembling a limb girdle muscular dystrophy, and intermediate phenotypes falling between UCMD and Bethlem muscular dystrophy. Despite clinical and immunohistochemical features highly suggestive of COL6-RD, some patients had remained without an identified causative variant in COL6A1, COL6A2 or COL6A3. With combined muscle RNA-sequencing and whole-genome sequencing we uncovered a recurrent, de novo deep intronic variant in intron 11 of COL6A1 (c.930+189C>T) that leads to a dominantly acting in-frame pseudoexon insertion. We subsequently identified and have characterised an international cohort of forty-four patients with this COL6A1 intron 11 causative variant, one of the most common recurrent causative variants in the collagen VI genes. Patients manifest a consistently severe phenotype characterised by a paucity of early symptoms followed by an accelerated progression to a severe form of UCMD, except for one patient with somatic mosaicism for this COL6A1 intron 11 variant who manifests a milder phenotype consistent with Bethlem muscular dystrophy. Characterisation of this individual provides a robust validation for the development of our pseudoexon skipping therapy. We have previously shown that splice-modulating antisense oligomers applied in vitro effectively decreased the abundance of the mutant pseudoexon-containing COL6A1 transcripts to levels comparable to the in vivo scenario of the somatic mosaicism shown here, indicating that this therapeutic approach carries significant translational promise for ameliorating the severe form of UCMD caused by this common recurrent COL6A1 causative variant to a Bethlem muscular dystrophy phenotype.

2.
Pediatr Res ; 95(6): 1611-1616, 2024 May.
Article in English | MEDLINE | ID: mdl-38233513

ABSTRACT

BACKGROUND: Infections cause significant morbidity and mortality in children with Severe Neurological Impairment (SNI). Alterations in immune cell numbers and function in children with neurodisability have been reported. We aimed to characterise neutrophil, monocyte and lymphocyte proportions and activation, at baseline and in response to stimulation with lipopolysaccharide, in children with SNI compared to healthy controls. METHODS: Whole blood samples of children with SNI and controls were incubated in the presence or absence of lipopolysaccharide (10 ng/ml). Monocyte and neutrophil function (Cluster of Differentiation (CD)11b, (TLR)-4 and CD66b expression) and lymphocytes were assessed by flow cytometry. Expression of genes involved in the inflammasome (NLR Family Pyrin Domain Containing(NLRP)-3, Apoptosis-Associated Speck-like protein (ASC) and Interleukin(IL)1ß) were assessed by PCR. RESULTS: Monocytes and CD8+ T cells were lower in children with SNI (n = 14). CD66b, was hyporesponsive and monocyte TLR4 was hyperresponsive to lipopolysaccharide in children with SNI compared to controls (n = 14). NLRP3 expression was higher at baseline and IL1ß expression was not upregulated in response to lipopolysaccharide in children with SNI in contrast to controls. CONCLUSION: We have found significant differences in immune regulation in children with SNI compared to controls which may provide a useful therapeutic target in the future. IMPACT: Children with SNI have reduced monocyte and CD8+ T cells. Neutrophils and monocytes in children with SNI show altered markers of activation in response to lipopolysaccharide. Expression of NLRP3 at the RNA level was higher at baseline in children with SNI. This study adds to the existing literature that children with neurological impairment have altered inflammatory and immune cell responses. This may provide a useful therapeutic target to reduce infection-related morbidity and mortality, and tertiary neurological injury in the future.


Subject(s)
Inflammasomes , Interleukin-1beta , Lipopolysaccharides , Monocytes , NLR Family, Pyrin Domain-Containing 3 Protein , Nervous System Diseases , Neutrophils , Toll-Like Receptor 4 , Humans , Monocytes/metabolism , Monocytes/immunology , Inflammasomes/metabolism , Inflammasomes/immunology , Neutrophils/metabolism , Neutrophils/immunology , Child , Female , Male , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Child, Preschool , Toll-Like Receptor 4/metabolism , Interleukin-1beta/metabolism , Interleukin-1beta/blood , Nervous System Diseases/immunology , Adolescent , GPI-Linked Proteins/metabolism , Case-Control Studies , Antigens, CD/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , CARD Signaling Adaptor Proteins/metabolism , CD11b Antigen/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Adhesion Molecules
3.
Sci Rep ; 13(1): 21292, 2023 12 02.
Article in English | MEDLINE | ID: mdl-38042898

ABSTRACT

Dysregulation of nitric oxide (NO) production can cause ischaemic retinal injury and result in blindness. How this dysregulation occurs is poorly understood but thought to be due to an impairment in NO synthase function (NOS) and nitro-oxidative stress. Here we investigated the possibility of correcting this defective NOS activity by supplementation with the cofactor tetrahydrobiopterin, BH4. Retinal ischaemia was examined using the oxygen-induced retinopathy model and BH4 deficient Hph-1 mice used to establish the relationship between NOS activity and BH4. Mice were treated with the stable BH4 precursor sepiapterin at the onset of hypoxia and their retinas assessed 48 h later. HPLC analysis confirmed elevated BH4 levels in all sepiapterin supplemented groups and increased NOS activity. Sepiapterin treatment caused a significant decrease in neuronal cell death in the inner nuclear layer that was most notable in WT animals and was associated with significantly diminished superoxide and local peroxynitrite formation. Interestingly, sepiapterin also increased inflammatory cytokine levels but not microglia cell number. BH4 supplementation by sepiapterin improved both redox state and neuronal survival during retinal ischaemia, in spite of a paradoxical increase in inflammatory cytokines. This implicates nitro-oxidative stress in retinal neurones as the cytotoxic element in ischaemia, rather than enhanced pro-inflammatory signalling.


Subject(s)
Biopterins , Retinal Diseases , Mice , Animals , Biopterins/metabolism , Retinal Diseases/drug therapy , Nitric Oxide/metabolism , Cell Death , Dietary Supplements , Ischemia/drug therapy
4.
Cell Cycle ; 22(11): 1380-1390, 2023 06.
Article in English | MEDLINE | ID: mdl-37183425

ABSTRACT

FBXW7 is the substrate recognition component of the E3 ubiquitin ligase SCFFBW7 complex which controls the levels of CYCLINE, c-MYC and HIF1α proteins crucial for cell growth and differentiation. Mutations in FBXW7 are frequently associated with tumourigenesis. While examining FBXW7 regulation we were compelled to reevaluate a commonly used anti-FBXW7 antibody. Retinal microvascular endothelial cells (RMEC) were exposed to normoxia (21% oxygen) or hypoxia (1% oxygen) for 24 h or treated with MG132 and protein extracted for western blotting. Flag-tagged FBXW7-α, ß or γ isoforms were transfected into HEK293A cells and processed using denaturing and native extraction protocols for western blotting or immunoprecipitation analysis. Two anti-FBXW7 antibodies were used, one raised to the unique FBXW7α N-terminus and the other to the C-terminus region common to all isoforms. Initial studies showed that the pan-isoform C-terminus antibody detected a single 64kDa band in RMEC rather than any of the predicted sizes for FBXW7. In contrast, expression of the isoform-specific constructs, detected with an anti-Flag antibody, confirmed the expected migratory distance of 110kDa, 68kDa and 65kDa for α, ß and γ respectfully. Similarly, the N-terminus FBXW7α antibody also detected the 110kDa product. Notably, the C-terminus antibody did not recognize any of the isoforms but continued to detect a 64kDa band in all samples, including the non-transfected controls. Immunoprecipitation confirmed this lack of specificity and the inability to detect overexpressed or endogenous FBXW7α in HEK293A cells and RMEC. A commonly used C-terminus FBXW7 antibody does not detect FBXW7 under standard western blotting conditions.


Subject(s)
F-Box Proteins , F-Box Proteins/genetics , F-Box Proteins/metabolism , Endothelial Cells/metabolism , F-Box-WD Repeat-Containing Protein 7/genetics , F-Box-WD Repeat-Containing Protein 7/metabolism , Cell Cycle/genetics , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Antibodies
5.
Eur J Paediatr Neurol ; 42: 42-46, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36525883

ABSTRACT

AIMS: To highlight the current diagnostic pathway for children with Spinal Muscular Atrophy (SMA) in Ireland. We look to identify points along the diagnostic pathway that may impede a timely diagnosis, and argue that newborn screening for SMA is the single best measure to remediate these delays. METHODS: Through retrospective chart review and an online questionnaire, we gathered SMA patient data outlining clinical characteristics and the route to diagnosis of the SMA cohort attending the National SMA Treatment centre at Children's Health Ireland. RESULTS: We found that 32 children were diagnosed with SMA in Ireland in the 15-years from 2007 to 2021, with twelve cases of SMA type I. Muscle weakness is the most commonly reported initial sign, and the GP is usually the first health provider to address parental concerns. Patients commonly experience delays in diagnosis due to factors such as varied SMA clinical phenotypes, and a lack of experience or awareness of SMA amongst community based health care practitioners. In spite of this, when patients do gain early access to tertiary diagnostics through prenatal or neonatal genetic testing, they then report rapid diagnosis and initiation of disease modifying therapy in the crucial pre-symptomatic window. CONCLUSION: We conclude that delays to diagnosis inherent within the current Irish system are pervasive and arise prior to engagement with tertiary services. All of these delays are remediable through the establishment of a dedicated SMA newborn screening programme.


Subject(s)
Muscular Atrophy, Spinal , Spinal Muscular Atrophies of Childhood , Pregnancy , Female , Infant, Newborn , Humans , Retrospective Studies , Muscular Atrophy, Spinal/diagnosis , Muscular Atrophy, Spinal/genetics , Spinal Muscular Atrophies of Childhood/genetics , Genetic Testing , Neonatal Screening
6.
Front Pediatr ; 9: 668544, 2021.
Article in English | MEDLINE | ID: mdl-34434904

ABSTRACT

Cerebral Palsy (CP) describes a heterogenous group of non-progressive disorders of posture or movement, causing activity limitation, due to a lesion in the developing brain. CP is an umbrella term for a heterogenous condition and is, therefore, descriptive rather than a diagnosis. Each case requires detailed consideration of etiology. Our understanding of the underlying cause of CP has developed significantly, with areas such as inflammation, epigenetics and genetic susceptibility to subsequent insults providing new insights. Alongside this, there has been increasing recognition of the multi-organ dysfunction (MOD) associated with CP, in particular in children with higher levels of motor impairment. Therefore, CP should not be seen as an unchanging disorder caused by a solitary insult but rather, as a condition which evolves over time. Assessment of multi-organ function may help to prevent complications in later childhood or adulthood. It may also contribute to an improved understanding of the etiology and thus may have an implication in prevention, interventional methods and therapies. MOD in CP has not yet been quantified and a scoring system may prove useful in allowing advanced clinical planning and follow-up of children with CP. Additionally, several biomarkers hold promise in assisting with long-term monitoring. Clinicians should be aware of the multi-system complications that are associated with CP and which may present significant diagnostic challenges given that many children with CP communicate non-verbally. A step-wise, logical, multi-system approach is required to ensure that the best care is provided to these children. This review summarizes multi-organ dysfunction in children with CP whilst highlighting emerging research and gaps in our knowledge. We identify some potential organ-specific biomarkers which may prove useful in developing guidelines for follow-up and management of these children throughout their lifespan.

7.
Cochrane Database Syst Rev ; 7: CD012756, 2021 07 05.
Article in English | MEDLINE | ID: mdl-34224134

ABSTRACT

BACKGROUND: Cerebral palsy (CP) is a heterogeneous group of non-progressive disorders of posture or movement, caused by a lesion of the developing brain. Osteoporosis is common in children with cerebral palsy, particularly in children with reduced gross motor function, and leads to an increased risk of fractures. Gross motor function in children with CP can be categorised using a tool called the Gross Motor Function Classification System (GMFCS). Bisphosphonate increases bone mineral density (BMD) and reduces fracture rates. Bisphosphonate is used widely in the treatment of adult osteoporosis. However, the use of bisphosphonate in children with CP remains controversial, due to a paucity of evidence and a lack of recent trials examining the efficacy and safety of bisphosphonate use in this population. OBJECTIVES: To examine the efficacy and safety of bisphosphonate therapy in the treatment of low BMD or secondary osteoporosis (or both) in children with cerebral palsy (GMFCS Levels III to V) who are under 18 years of age. SEARCH METHODS: In September 2020, we searched CENTRAL, MEDLINE, Embase, six other databases, and two trial registers for relevant studies. We also searched the reference lists of relevant systematic reviews, trials, and case studies identified by the search, and contacted the authors of relevant studies in an attempt to identify unpublished literature. SELECTION CRITERIA: All relevant randomised controlled trials (RCTs), and quasi-RCTs, comparing at least one bisphosphonate (given at any dose, orally or intravenously) with placebo or no drug, for the treatment of low BMD or osteoporosis in children up to 18 years old, with cerebral palsy (GMFCS Levels III to V). DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We were unable to conduct any meta-analyses due to insufficient data, and therefore provide a narrative assessment of the results. MAIN RESULTS: We found two relevant RCTs (34 participants). Both studies included participants with non-ambulatory CP or CP and osteoporosis. Participants in both studies were similar in severity of CP, age distribution, and sex distribution. The two trials used different bisphosphonate medications and different intervention durations, but further comparison of the interventions was not possible due to a lack of published data from one trial. One trial received funding and support from research, academic, and hospital foundations, with pharmaceutical companies providing components of the calcium and vitamin supplement; the other trial did not report sources of funding. We judged one study at an overall high risk of bias; the other as overall unclear risk of bias. PRIMARY OUTCOME: Compared to placebo or no treatment, both studies provided very low certainty evidence of improved BMD at least four months post-intervention in children treated with bisphosphonate. Only one study (12 participants) provided sufficient detail to assess a measure of the effect, and reported an improvement at six months post-intervention in lumbar spine z-score (mean difference (MD) 18%, 95% confidence interval (CI) 6.57 to 29.43; very low certainty evidence). SECONDARY OUTCOMES: Very low certainty evidence from one study found that bisphosphonate reduced serum N-telopeptides (NTX) more than placebo; the other study reported that both bisphosphonate plus alfacalcidol and alfacalcidol alone reduced NTX, but did not compare groups. One study reported inconclusive results between groups for serum bone-specific alkaline phosphatase (BAP). The other study reported that both bisphosphonate plus alfacalcidol and alfacalcidol alone reduced BAP, but did not compare groups. Neither study reported data for the effect of bisphosphonate treatment on changes in volumetric BMD in the distal radius or tibia, changes in fracture frequency, bone pain, or quality of life. One study reported that two participants had febrile events noted during their first dosing schedule, but no further adverse events were reported in either relevant study. AUTHORS' CONCLUSIONS: Based on the available evidence, there is very low certainty evidence that bisphosphonate treatment may improve bone health in children with cerebral palsy. We could only include one study with 14 participants in the assessment of the effect size; therefore, the precision of the effect estimate is low. We could only evaluate one planned primary outcome, as there was insufficient detail reported in the relevant studies. Further research from RCTs on the effect and safety of bisphosphonate to improve bone health in children with cerebral palsy is required. These studies should clarify the optimal standard treatment regarding weight-bearing exercises, vitamin D and calcium supplementation, and should include fracture frequency as a primary outcome.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Bone Density/drug effects , Cerebral Palsy/complications , Diphosphonates/therapeutic use , Osteoporosis/drug therapy , Adolescent , Alkaline Phosphatase/blood , Bias , Child , Child, Preschool , Collagen Type I/blood , Female , Fractures, Spontaneous/prevention & control , Humans , Hydroxycholecalciferols/therapeutic use , Infant , Male , Osteoporosis/blood , Peptides/blood , Randomized Controlled Trials as Topic
8.
Acta Paediatr ; 110(8): 2352-2356, 2021 08.
Article in English | MEDLINE | ID: mdl-33942377

ABSTRACT

AIM: Neonatal encephalopathy (NE) is associated with altered cognitive, motor, sensory abilities and behavioural outcomes. This case-control study aimed to assess whether Quality of Life (QoL) and sleep disorders are affected in older children following NE compared to age-matched controls. METHODS: Children at school-age post-NE were recruited and compared to age-matched controls. Sleep and QoL were assessed with the Pediatric Quality of Life Inventory and the Child Sleep Habit Questionnaire. RESULTS: One hundred children were recruited with an age range of 4-6 years, including children post-NE (n=45) and age-matched controls (n = 55). Significantly higher pathological sleep scores were evident in 58% of children post-NE compared to controls (43.8 vs 40.2; p = 0.001). Children post-NE had increased bedtime resistance (p = 0.028) and sleep anxiety (p = 0.01) compared to controls. Children in the post-NE group had lower total QoL scores versus controls (mean score 82.5 vs 95.8; p < 0.01). Children with mild NE also had lower total QoL scores than controls (90.0 vs 95.8, p = 0.003). There was a strong correlation between low QoL with high total sleep scores (Rho 0.339, p = 0.014). CONCLUSION: There were high rates of sleep issues in school-aged children with mild and moderate-severe NE. Consideration and management of sleep problems may improve QoL in childhood post-NE.


Subject(s)
Brain Diseases , Sleep Wake Disorders , Case-Control Studies , Child , Child, Preschool , Humans , Infant, Newborn , Quality of Life , Sleep , Sleep Wake Disorders/epidemiology , Sleep Wake Disorders/etiology , Surveys and Questionnaires
9.
Dev Med Child Neurol ; 63(4): 407-412, 2021 04.
Article in English | MEDLINE | ID: mdl-33185287

ABSTRACT

AIM: To examine pro- and anti-inflammatory cytokines in children with cerebral palsy (CP) at baseline and in response to endotoxin (lipopolysaccharide), and correlate outcomes compared with age-matched comparisons, to evaluate their ability to mount an immune response. METHOD: Serum cytokines were assessed in 12 children (eight males, four females; mean age 10y 1mo [SD 1y 8mo], 6-16y) with CP against 12 age-matched comparisons (eight males, four females; mean age 9y 1mo [SD 1y 1mo]). Pro- and anti-inflammatory cytokines (interleukin-1ß, interleukin-2, interleukin-6, interleukin-8, interleukin-10, interleukin-18, tumour necrosis factor [TNF]-α, TNF-ß, interferon-γ, granulocyte-macrophage colony-stimulating factor [GM-CSF], vascular endothelial growth factor [VEGF], erythropoietin, and interleukin-1 receptor antagonist) were measured at baseline and in response to in vitro simulation with lipopolysaccharide by multiplex enzyme-linked immunosorbent assay. RESULTS: Significantly higher erythropoietin was found at baseline in children with CP compared with the comparison group. There was a strong response to lipopolysaccharide for interleukin-8, VEGF, TNF-α, and GM-CSF in both children with CP and the comparison group; however, there was significant lipopolysaccharide hyporesponsiveness in children with CP compared with the comparison group for interleukin-1α, interleukin-1ß, interleukin-2, and interleukin-6. INTERPRETATION: Altered cytokine responses in children with CP compared with the comparison group demonstrate an altered inflammatory state that may contribute to ongoing sequelae and could be a target for therapy. WHAT THIS PAPER ADDS: Altered inflammatory responses persist in children with cerebral palsy (CP). Erythropoietin is elevated in children with CP compared with the comparison group. Children with CP have reduced interleukin-1α, interleukin-1ß, interleukin-2, and interleukin-6 inflammatory responses to lipopolysaccharide.


Subject(s)
Cerebral Palsy/blood , Cytokines/blood , Adolescent , Child , Female , Granulocyte-Macrophage Colony-Stimulating Factor/blood , Humans , Inflammation/blood , Interleukins/blood , Male , Tumor Necrosis Factor-alpha/blood , Vascular Endothelial Growth Factor A/blood
10.
Eur J Paediatr Neurol ; 29: 81-86, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32951992

ABSTRACT

BACKGROUND: Severe Neurological Impairment (SNI) is a term for which there is no consistently used definition. This may hamper consistency in the reporting of research in the area and communication between professionals involved in the care of those with SNI. OBJECTIVE: We aimed to create an international, multidisciplinary, consensus-based definition of SNI. DESIGN: The Delphi method was employed to reach consensus on the definition of SNI. METHOD: An international, multi-disciplinary expert panel was recruited. The process proceeded over three rounds with feedback provided to panellists between each of them. Consensus was defined as 70% agreement. A working definition was created and, following presentation at an international meeting and consultation with parent representatives, further refined, to create a finalised definition. RESULTS: Thirty-four expert panellists commenced the process. Six items reached the threshold of consensus. The finalised definition is as follows: "Severe Neurological Impairment describes a group of disorders of the central nervous system which arise in childhood, resulting in motor impairment, cognitive impairment and medical complexity, where much assistance is required with activities of daily living. The impairment is permanent but can be progressive or static." CONCLUSION: A consensus-based definition of SNI which includes multi-disciplinary, international and parental input has been created. This should prove useful for clinical, research and resource-planning purposes.


Subject(s)
Developmental Disabilities , Nervous System Diseases , Child , Consensus , Delphi Technique , Humans
11.
BMC Neurol ; 20(1): 115, 2020 Mar 30.
Article in English | MEDLINE | ID: mdl-32228505

ABSTRACT

BACKGROUND: Cytokines are possible mediators of neuroinflammation and associated with adverse outcome in neonatal encephalopathy (NE). Our aim was to explore cytokine response in children with Neonatal Encephalopathy (NE) at school age compared to age-matched controls. METHOD: Follow up at school age, children who had NE and age-matched controls were assessed for their cytokine responses and neurodevelopment outcome. Pro- and anti-inflammatory cytokines in the serum, [Interleukin (IL)-1α, IL-1ß, IL-2, IL-6, IL-8, IL-18, Tumor necrosis factor (TNF)-α, TNF ß, Interferon (IFN)-γ, granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), erythropoietin (EPO), IL-10 & IL-1RA] were measured at baseline and in response to in vitro stimulation with lipopolysaccharide (LPS: endotoxin). RESULTS: GM-CSF, TNF-ß, IL-2 IL-6 and IL-8 were significantly elevated at school age following NE (n = 40) compared to controls (n = 37). A rise in GM-CSF, IL-8, TNF-α, IL-1ß, & IL-6 were seen in NE group following LPS stimulation. Relative LPS hypo-responsiveness was also noted in children with severe NE with IL-10, VEGF, EPO and TNF-ß. Elevated TNF-ß was associated with low gross motor scores on assessment at school age. CONCLUSION: School-age children post-NE had significantly altered cytokine responses to endotoxin compared to controls. TNF-ß was associated with adverse developmental outcomes. This suggests the inflammatory process may persist into childhood and a longer therapeutic window may be available for neuroprotection therapies.


Subject(s)
Asphyxia Neonatorum/complications , Asphyxia Neonatorum/immunology , Cytokines/blood , Neurodevelopmental Disorders/etiology , Neurodevelopmental Disorders/immunology , Brain Diseases/etiology , Brain Diseases/immunology , Child , Female , Humans , Infant, Newborn , Male
12.
Cardiovasc Res ; 116(2): 393-405, 2020 02 01.
Article in English | MEDLINE | ID: mdl-30937452

ABSTRACT

AIMS: Cord blood-derived endothelial colony-forming cells (CB-ECFCs) are a defined progenitor population with established roles in vascular homeostasis and angiogenesis, which possess low immunogenicity and high potential for allogeneic therapy and are highly sensitive to regulation by reactive oxygen species (ROS). The aim of this study was to define the precise role of the major ROS-producing enzyme, NOX4 NADPH oxidase, in CB-ECFC vasoreparative function. METHODS AND RESULTS: In vitro CB-ECFC migration (scratch-wound assay) and tubulogenesis (tube length, branch number) was enhanced by phorbol 12-myristate 13-acetate (PMA)-induced superoxide in a NOX-dependent manner. CB-ECFCs highly-expressed NOX4, which was further induced by PMA, whilst NOX4 siRNA and plasmid overexpression reduced and potentiated in vitro function, respectively. Increased ROS generation in NOX4-overexpressing CB-ECFCs (DCF fluorescence, flow cytometry) was specifically reduced by superoxide dismutase, highlighting induction of ROS-specific signalling. Laser Doppler imaging of mouse ischaemic hindlimbs at 7 days indicated that NOX4-knockdown CB-ECFCs inhibited blood flow recovery, which was enhanced by NOX4-overexpressing CB-ECFCs. Tissue analysis at 14 days revealed consistent alterations in vascular density (lectin expression) and eNOS protein despite clearance of injected CB-ECFCs, suggesting NOX4-mediated modulation of host tissue. Indeed, proteome array analysis indicated that NOX4-knockdown CB-ECFCs largely suppressed tissue angiogenesis, whilst NOX4-overexpressing CB-ECFCs up-regulated a number of pro-angiogenic factors specifically-linked with eNOS signalling, in parallel with equivalent modulation of NOX-dependent ROS generation, suggesting that CB-ECFC NOX4 signalling may promote host vascular repair. CONCLUSION: Taken together, these findings indicate a key role for NOX4 in CB-ECFCs, thereby highlighting its potential as a target for enhancing their reparative function through therapeutic priming to support creation of a pro-reparative microenvironment and effective post-ischaemic revascularization.


Subject(s)
Endothelial Progenitor Cells/transplantation , Ischemia/surgery , Muscle, Skeletal/blood supply , NADPH Oxidase 4/metabolism , Neovascularization, Physiologic , Animals , Cell Movement , Cells, Cultured , Cellular Microenvironment , Disease Models, Animal , Endothelial Progenitor Cells/enzymology , Fetal Blood/cytology , Hindlimb , Humans , Ischemia/enzymology , Ischemia/genetics , Ischemia/physiopathology , Mice, Inbred NOD , NADPH Oxidase 4/genetics , Reactive Oxygen Species/metabolism , Recovery of Function , Signal Transduction
13.
Dev Med Child Neurol ; 62(3): 277-282, 2020 03.
Article in English | MEDLINE | ID: mdl-31237356

ABSTRACT

Severe neurological impairment (SNI) is a term commonly used in the medical literature, though there is no agreed definition. This limits opportunities for research into healthcare needs, treatment opportunities, resource planning, and outcome. We reviewed the literature to establish consistency of use of the term and to place it in the context of other commonly employed terms used to describe children with severe, complex medical needs. Forty-two articles were included for full-text analysis, with 23 including a definition of SNI. Motor impairment, intellectual disability, communication difficulties, and increased care needs were included in the definition in 80%, 70%, 30%, and 13% of papers respectively. Dependence on others for decision-making, chronicity, and distinction between disorders of the central nervous system and peripheral nervous system were less frequently included. There is wide variation in the use of the term SNI. A consensus-based definition of this term would be useful to facilitate future research. WHAT THIS PAPER ADDS: There is inconsistency in use of the term severe neurological impairment (SNI), limiting research efforts. In defining SNI, considerations are mobility, intellectual disability, communication difficulties, and increased care needs. Distinction between acute and chronic, central and peripheral nervous system disorders, and dependence on others for decision-making were less significant.


DEFICIENCIA NEUROLÓGICO SEVERO: UNA REVISIÓN DE LA DEFINICIÓN: El deficiencia neurológico severo es un término comúnmente utilizado en la literatura médica, aunque no existe una definición acordada. Esto limita las oportunidades de investigación sobre necesidades de atención médica, oportunidades de tratamiento, planificación de recursos y resultados. Revisamos la literatura para establecer la coherencia en el uso del término y colocarlo en el contexto de otros términos empleados comúnmente que se utilizan para describir a los niños con necesidades médicas graves y complejas. Se incluyeron 42 artículos para el análisis de texto completo, de los cuales 23 incluían una definición de deficiencia neurológico severo. La discapacidad motora, la discapacidad intelectual, las dificultades de comunicación y el aumento de las necesidades de atención se incluyeron en la definición en 80%, 70%, 30% y 13% de los artículos, respectivamente. La dependencia de otros para la toma de decisiones, la cronicidad y la distinción entre los trastornos del sistema nervioso central y el sistema nervioso periférico se incluyeron con menos frecuencia. Existe una amplia variación en el uso del término deficiencia neurológico severo. Una definición basada en el consenso de este término sería útil para facilitar futuras investigaciones.


DEFICIÊNCIA NEUROLÓGICA SEVERA: UMA REVISÃO DA DEFINIÇÃO: A deficiência neurológica severa (DNS) é uma termo comumente usado na literatura médica, embora não tenha definição consensual. Isso limita as oportunidades de pesquisas sobre necessidades de saúde, oportunidades de tratamento, planejamento de recursos, e resultados. Nós revisamos a literature para estabelecer a consistência do uso do termo, e para colocá-lo no contexto de outros termos comumente empregados para descrever crianças com necessidades médicas severas e complexas. Quarenta e dois artigos foram incluídos para análise dos textos completes, com 23 includindo uma definição de DNS. Deficiência motora, deficiência intelectual, dificuldades de comunicação, e necessidades de cuidado aumentadas foram incluídas na definição 80%, 70%, 30%, e 13% dos artigos, respectivamente. Dependência de outros para tomada de decisões, cronicidade, e distinção entre desordens do sistema nervoso central e periférico foram menos frequentemente incluídas. Há grande variação no uso do termo DNS. Uma definição do termo baseada em consenso seria útil para facilitar futuras pesquisas.


Subject(s)
Nervous System Diseases/classification , Nervous System Diseases/diagnosis , Terminology as Topic , Child , Humans , Severity of Illness Index
14.
J Med Internet Res ; 21(6): e13689, 2019 06 04.
Article in English | MEDLINE | ID: mdl-31165715

ABSTRACT

BACKGROUND: Postnatal depression and caregiving difficulties adversely affect mothers, infants, and later childhood development. In many countries, resources to help mothers and infants are limited. Online group-based nurse-led interventions have the potential to help address this problem by providing large numbers of mothers with access to professional and peer support during the postnatal period. OBJECTIVE: This study tested the effectiveness of a 4-month online group-based nurse-led intervention delivered when infants were aged 2 to 6 months as compared with standard care outcomes. METHODS: The study was a block randomized control trial. Mothers were recruited at the time they were contacted for the postnatal health check offered to all mothers in South Australia. Those who agreed to participate were randomly assigned to the intervention or standard care. The overall response rate was 63.3% (133/210). Primary outcomes were the level of maternal depressive symptoms assessed with the Edinburgh Postnatal Depression Scale (EPDS) and quality of maternal caregiving assessed using the Parenting Stress Index (PSI; competence and attachment subscales), the Parenting Sense of Competence Scale (PSCS), and the Nursing Child Assessment Satellite Training Scale. Assessments were completed at baseline (mean child age 4.9 weeks [SD 1.4]) and again when infants were aged 8 and 12 months. RESULTS: Outcomes were evaluated using linear generalized estimating equations adjusting for postrandomization group differences in demographic characteristics and the outcome score at baseline. There were no significant differences in the intervention and standard care groups in scores on the PSI competence subscale (P=.69) nor in the PSCS (P=.11). Although the group by time interaction suggested there were differences over time between the EPDS and PSI attachment subscale scores in the intervention and standard care groups (P=.001 and P=.04, respectively), these arose largely because the intervention group had stable scores over time whereas the standard care group showed some improvements between baseline and 12 months. Mothers engaged well with the intervention with at least 60% (43/72) of mothers logging-in once per week during the first 11 weeks of the intervention. The majority of mothers also rated the intervention as helpful and user-friendly. CONCLUSIONS: Mothers reported that the intervention was helpful, and the app was described as easy to use. As such, it appears that support for mothers during the postnatal period, provided using mobile phone technology, has the potential to be an important addition to existing services. Possible explanations for the lack of differences in outcomes for the 2 groups in this study are the failure of many mothers to use key components of the intervention and residual differences between the intervention and standard care groups post randomization. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616001732471; http://www.ANZCTR.org.au/ACTRN12616001732471.aspx (archived on WebCite as http://www.webcitation.org/77zo30GDw).


Subject(s)
Depression, Postpartum/therapy , Mobile Applications/standards , Mothers/education , Parenting/psychology , Adult , Female , Humans , Infant , Male , Nurses , Young Adult
15.
JMIR Res Protoc ; 8(1): e11549, 2019 Jan 16.
Article in English | MEDLINE | ID: mdl-30664487

ABSTRACT

BACKGROUND: Postnatal depression adversely affects many mothers and infants with good evidence that caregiving difficulties associated with depressive symptoms play a key role in later adverse childhood outcomes. In many countries, there is only limited support available for women who experience symptoms of depression during the postnatal period, particularly those experiencing subthreshold symptom levels. Furthermore, mental health services and community family health services in many countries tend to focus primarily on providing help for depressive symptoms or maternal caregiving, respectively, despite these problems commonly being comorbid. Group-based nurse-led interventions delivered over the Web through mobile phone "apps" have the potential to be a cost-effective method of providing a large number of mothers with easy access to integrated support for both maternal depressive symptoms and caregiving difficulties. OBJECTIVE: This paper describes the protocol for a pragmatic randomized controlled trial of a 4-month group-based nurse-led intervention delivered over the Web when infants were 2-6 months. The primary aims of the trial are to determine whether the intervention (1) reduces levels of maternal depressive symptoms and (2) improves the quality of maternal caregiving when infants are 8-12 months of age. METHODS: The trial aimed to recruit and randomize 160 mothers of infants aged 2-8 weeks to either the intervention (eMums plus) or standard care. Assessments were completed when infants were aged 1-2 (preintervention), 8, and 12 months. The primary outcomes were the level of maternal depressive symptoms and the quality of maternal caregiving assessed when infants were aged 12 months. The intervention provided specific support for problems with mood and problems with caregiving. The intervention was delivered by community health nurses as a part of routine service delivery to mothers via a mobile phone app. RESULTS: Participant recruitment was carried out from March to July 2017. Follow-up data collection was completed in mid-2018. Data analysis has commenced. CONCLUSIONS: In the past, many mothers participated in nurse-led face-to-face groups postnatally. However, mothers' groups held in clinics can be difficult for busy mothers to attend. The eMums intervention was delivered over the Web by nurses, allowing easy access by mothers early in an infant's life. The intervention was evaluated while delivered as part of the routine service practice by community child health nurses. The advantage of evaluating the effectiveness of the intervention in the routine service practice is that if it is found to be effective, it can be more easily adopted by the service provider than if it had been assessed in an efficacy trial. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/11549.

16.
Stem Cells ; 37(2): 226-239, 2019 02.
Article in English | MEDLINE | ID: mdl-30372556

ABSTRACT

The mortality rate for (cardio)-vascular disease is one of the highest in the world, so a healthy functional endothelium is of outmost importance against vascular disease. In this study, human induced pluripotent stem (iPS) cells were reprogrammed from 1 ml blood of healthy donors and subsequently differentiated into endothelial cells (iPS-ECs) with typical EC characteristics. This research combined iPS cell technologies and next-generation sequencing to acquire an insight into the transcriptional regulation of iPS-ECs. We identified endothelial cell-specific molecule 1 (ESM1) as one of the highest expressed genes during EC differentiation, playing a key role in EC enrichment and function by regulating connexin 40 (CX40) and eNOS. Importantly, ESM1 enhanced the iPS-ECs potential to improve angiogenesis and neovascularisation in in vivo models of angiogenesis and hind limb ischemia. These findings demonstrated for the first time that enriched functional ECs are derived through cell reprogramming and ESM1 signaling, opening the horizon for drug screening and cell-based therapies for vascular diseases. Therefore, this study showcases a new approach for enriching and enhancing the function of induced pluripotent stem (iPS) cell-derived ECs from a very small amount of blood through ESM1 signaling, which greatly enhances their functionality and increases their therapeutic potential. Stem Cells 2019;37:226-239.


Subject(s)
Endothelial Cells/metabolism , Induced Pluripotent Stem Cells/metabolism , Neoplasm Proteins/metabolism , Proteoglycans/metabolism , Cell Differentiation/physiology , Cellular Reprogramming/physiology , Endothelial Cells/cytology , Humans , Induced Pluripotent Stem Cells/cytology , Neoplasm Proteins/genetics , Proteoglycans/genetics , Signal Transduction
17.
Invest Ophthalmol Vis Sci ; 58(1): 230-241, 2017 01 01.
Article in English | MEDLINE | ID: mdl-28114584

ABSTRACT

Purpose: Endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) has important vasoprotective functions that are compromised in the vasodegenerative phase of retinopathy of prematurity, owing to hyperoxia-induced depletion of the essential NOS cofactor BH4. Because modulating eNOS function can be beneficial or detrimental, our aim was to investigate the effect of BH4 supplementation on eNOS function and vascular regression in hyperoxia. Methods: Endothelial-specific eNOS-green fluorescent protein (GFP) overexpressing mice at postnatal day 7 (P7) were exposed to hyperoxia for 48 hours in the presence or absence of supplemental BH4, achieved by administration of sepiapterin, a stable BH4 precursor. Tissue was collected either for retinal flat mounts that were stained with lectin to determine the extent of vessel coverage or for analysis of BH4 by high-performance liquid chromatography, nitrotyrosine (NT) marker by Western blotting, VEGF expression by ELISA, and NOS activity by arginine-to-citrulline conversion. Primary retinal microvascular endothelial cells (RMEC) were similarly treated, and hyperoxia-induced damage was determined. Results: Sepiapterin effectively enhanced BH4 levels in hyperoxia-exposed retinas and brains, elevated NOS activity, and reduced NT-modified protein, leading to reversal of the exacerbated vasoregression observed in the presence of eNOS overexpression. In RMECs, hyperoxia-mediated depletion of BH4 dysregulated the redox balance by reducing nitrite and elevating superoxide and impaired proliferative ability. BH4 supplementation restored normal RMEC proliferation in vitro and also in vivo, providing a mechanistic link with the enhanced vascular coverage in eNOS-GFP retinas. Conclusions: These results demonstrate that BH4 supplementation corrects hyperoxia-induced RMEC dysfunction and preserves vascular integrity by enhancing eNOS function.


Subject(s)
Biopterins/analogs & derivatives , Endothelium, Vascular/enzymology , Hyperoxia/prevention & control , Nitric Oxide Synthase Type III/metabolism , Retinal Vessels/enzymology , Retinopathy of Prematurity/prevention & control , Animals , Animals, Newborn , Biopterins/pharmacology , Blotting, Western , Cells, Cultured , Disease Models, Animal , Endothelium, Vascular/drug effects , Endothelium, Vascular/pathology , Enzyme-Linked Immunosorbent Assay , Humans , Hyperoxia/complications , Hyperoxia/metabolism , Mice , Mice, Inbred C57BL , Nitric Oxide Synthase Type III/drug effects , Retinal Vessels/drug effects , Retinal Vessels/pathology , Retinopathy of Prematurity/etiology , Retinopathy of Prematurity/pathology
18.
BMJ Open ; 6(8): e009967, 2016 08 05.
Article in English | MEDLINE | ID: mdl-27496227

ABSTRACT

OBJECTIVES: To identify factors predicting use, adherence and attrition with a nurse-moderated web-based group intervention designed to support mothers of infants aged 0-6 months. DESIGN: 9-Month observational study. SETTING: Community maternal and child health service. PARTICIPANTS: 240 mothers attending initial postnatal health checks at community clinics who were randomly assigned to the intervention arm of a pragmatic preference randomised trial (total randomised controlled trial, n=819; response rate=45%). INTERVENTION: In the first week (phase I), mothers were assisted with their first website login by a research assistant. In weeks 2-7 (phase II), mothers participated in the web-based intervention with an expectation of weekly logins. The web-based intervention was comparable to traditional face-to-face new mothers' groups. During weeks 8-26 (phase III), mothers participated in an extended programme at a frequency of their choosing. PRIMARY OUTCOME MEASURES: Number of logins and posted messages. Standard self-report measures assessed maternal demographic and psychosocial characteristics. RESULTS: In phase II, the median number of logins was 9 logins (IQR=1-25), and in phase III, it was 10 logins (IQR=0-39). Incident risk ratios from multivariable analyses indicated that compared to mothers with the lowest third of logins in phase I, those with the highest third had 6.43 times as many logins in phase II and 7.14 times in phase III. Fifty per cent of mothers logged-in at least once every 30 days for 147 days after phase I and 44% logged-in at least once in the last 30 days of the intervention. Frequency of logins during phase I was a stronger predictor of mothers' level of engagement with the intervention than their demographic and psychosocial characteristics. CONCLUSIONS: Mothers' early use of web-based interventions could be employed to customise engagement protocols to the circumstances of individual mothers with the aim of improving adherence and reducing attrition with web-based interventions. TRIAL REGISTRATION NUMBER: ACTRN12613000204741; Results.


Subject(s)
Internet/statistics & numerical data , Maternal-Child Health Services , Maternal-Child Nursing/methods , Patient Compliance/statistics & numerical data , Adult , Australia , Female , Humans , Infant , Infant Health , Infant, Newborn , Kaplan-Meier Estimate , Male , Maternal Health , Multivariate Analysis , Pragmatic Clinical Trials as Topic , Proportional Hazards Models , Self Report
19.
Int J Nanomedicine ; 10: 7183-96, 2015.
Article in English | MEDLINE | ID: mdl-26648722

ABSTRACT

We report the formulation of novel composite nanoparticles that combine the high transfection efficiency of cationic peptide-DNA nanoparticles with the biocompatibility and prolonged delivery of polylactic acid-polyethylene glycol (PLA-PEG). The cationic cell-penetrating peptide RALA was used to condense DNA into nanoparticles that were encapsulated within a range of PLA-PEG copolymers. The composite nanoparticles produced exhibited excellent physicochemical properties including size <200 nm and encapsulation efficiency >80%. Images of the composite nanoparticles obtained with a new transmission electron microscopy staining method revealed the peptide-DNA nanoparticles within the PLA-PEG matrix. Varying the copolymers modulated the DNA release rate >6 weeks in vitro. The best formulation was selected and was able to transfect cells while maintaining viability. The effect of transferrin-appended composite nanoparticles was also studied. Thus, we have demonstrated the manufacture of composite nanoparticles for the controlled delivery of DNA.


Subject(s)
Gene Transfer Techniques , Nanoparticles/chemistry , Peptides/chemistry , Polyethylene Glycols/chemistry , Cations , Cell Line, Tumor , Cell Survival , Cell-Penetrating Peptides/chemistry , DNA/metabolism , Electrophoretic Mobility Shift Assay , Humans , Nanoparticles/ultrastructure , Particle Size , Temperature , Transfection
20.
Am J Pathol ; 185(6): 1769-82, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25913075

ABSTRACT

Retinopathy of prematurity is a sight-threatening complication of premature birth caused by nitro-oxidative insult to the developing retinal vasculature during therapeutic hyperoxia exposure and later ischemia-induced neovascularization on supplemental oxygen withdrawal. In the vasodegenerative phase, during hyperoxia, defective endothelial nitric oxide synthase (NOS) produces reactive oxygen and nitrogen free radicals rather than vasoprotective nitric oxide for unclear reasons. Crucially, normal NOS function depends on availability of the cofactor (6R)-5,6,7,8-tetrahydrobiopterin (BH4). Because BH4 synthesis is controlled enzymatically by GTP cyclohydrolase (GTPCH), we used GTPCH-depleted mice [hyperphenylalaninemia strain (hph1)] to investigate the impact of hyperoxia on BH4 bioavailability and retinal vascular pathology in the neonate. Hyperoxia decreased BH4 in retinas, lungs, and aortas in all experimental groups, resulting in a dose-dependent decrease in NOS activity and, in the wild-type group, elevated NOS-derived superoxide. Retinal dopamine levels were similarly diminished, consistent with the dependence of tyrosine hydroxylase on BH4. Despite greater depletion of BH4, the hph(+/-) and hph1(-/-) groups did not show exacerbated hyperoxia-induced vessel closure, but exhibited greater vascular protection and reduced progression to neovascular disease. This vasoprotective effect was independent of enhanced circulating vascular endothelial growth factor (VEGF), which was reduced by hyperoxia, but to local retinal ganglion cell layer-derived VEGF. In conclusion, a constitutively higher level of VEGF expression associated with retinal development protects GTPCH-deficient neonates from oxygen-induced vascular damage.


Subject(s)
Biopterins/analogs & derivatives , Hyperoxia/metabolism , Nitric Oxide Synthase/metabolism , Retina/metabolism , Retinopathy of Prematurity/metabolism , Animals , Biopterins/metabolism , Female , Hyperoxia/pathology , Male , Mice , Retina/pathology , Retinopathy of Prematurity/pathology , Vascular Endothelial Growth Factor A/metabolism
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