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1.
J Paediatr Child Health ; 57(11): 1795-1804, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34792231

RESUMO

More than 8 billion tonnes of plastic were produced between 1950 and 2015, that is 1 tonne for every man, woman and child on our planet. Global plastic production has been growing exponentially with an annual growth rate of 8.4% since 1950, equating to approximately 380 million tonnes per annum. A further 50 kg of plastic is now being produced for each person every year with production continuing to accelerate. Here, we discuss the human and planetary health hazards of all that plastic. We consider each step in the journey of these complex and pervasive industrial materials: from their synthesis predominantly from fossil fuel feedstocks, through an often-brief consumer use as plastic products, and onto waste streams as fuel, permanent landfill or as unmanaged waste in our environment, food, air and bodies.


Assuntos
Planetas , Plásticos , Criança , Humanos , Masculino
2.
Muscle Nerve ; 62(3): 404-412, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32497302

RESUMO

BACKGROUND: After facial nerve injury and surgical repair in rats, recovery of vibrissal whisking is associated with a high proportion of mono-innervated neuro-muscular junctions (NMJs). Our earlier work with Sprague Dawley (SD)/Royal College of Surgeons (RCS) rats, which are blind and spontaneously restore NMJ-monoinnervation and whisking, showed correlations between functional recovery and increase of fibroblast growth factor-2 (FGF2) and brain-derived neurotrophic factor (BDNF) in denervated vibrissal muscles. METHODS: We used normally sighted rats (Wistar), in which NMJ-polyinnervation is highly correlated with poor whisking recovery, and injected the vibrissal muscle levator labii superioris (LLS) with combinations of BDNF, anti-BDNF, and FGF2 at different postoperative periods after facial nerve injury. RESULTS: Rats receiving anti-BDNF+FGF2 showed low NMJ-polyinnervation and best recovery of whisking amplitude. CONCLUSIONS: Restoration of target reinnervation after peripheral nerve injury requires a complex mixture of trophic factors with a specific time course of availability for each of them.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/imunologia , Traumatismos do Nervo Facial/tratamento farmacológico , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Regeneração Nervosa/fisiologia , Recuperação de Função Fisiológica/fisiologia , Vibrissas/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Denervação , Músculos Faciais/efeitos dos fármacos , Músculos Faciais/inervação , Músculos Faciais/fisiopatologia , Traumatismos do Nervo Facial/fisiopatologia , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/efeitos dos fármacos
3.
Spinal Cord ; 58(12): 1291-1300, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32457515

RESUMO

STUDY DESIGN: Qualitative survey. OBJECTIVES: Examine clinicians' perspectives on adherence to published evidence-based guidelines and clinician-perceived barriers, and facilitators to optimising inpatient bladder management within one Spinal Cord Injury (SCI) service. SETTING: Surgical Hospital (acute care) and SCI Unit (sub-acute, rehabilitation) in Western Australia (WA). METHODS: Clinicians reviewed an 'Evidence Matrix' summarising published clinical practice guidelines and recommendations for SCI bladder management. Focus groups examined the extent to which current practice adhered to recommendations and identified perceived barriers and facilitators to optimal management. Data were analysed thematically using a deductive approach. RESULTS: Current management closely mirrors published recommendations. Key facilitators included long-standing prioritisation of rapid progression from urethral indwelling (IDC) to a 6 hourly intermittent catheterisation (IC) protocol; regular competency audits of catheterisation technique; and a Spinal Urology Clinical Nurse Consultant (CNC) position. Barriers included limited resources/staffing; restricted access to Neuro-urology consultation; inter-disciplinary communication gaps; and delays in determining and implementing long-term bladder management. CONCLUSIONS: Inpatient SCI bladder care in WA closely emulates published evidence, although adherence at other sites may reveal different practices. Bladder management was found to have been facilitated by a strong culture of practice led by Neuro-urologists, informed by evidence and embraced by Senior Clinicians. Further reduction in duration of initial IDC, provision of early and ongoing Neuro-urology consultations as part of standard care, increased interdisciplinary communication and dedicated SCI Urology theatre lists would further optimise management.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinaria Neurogênica , Humanos , Pacientes Internados , Estudos Longitudinais , Traumatismos da Medula Espinal/terapia , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/terapia
4.
Spinal Cord ; 58(1): 25-34, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31388122

RESUMO

STUDY DESIGN: Retrospective audit. OBJECTIVES: Examine factors associated with urinary tract infection (UTI), UTI incidence and impact on hospital length of stay (LOS) in new, inpatient adult traumatic spinal cord injury (SCI). SETTING: Western Australian Hospitals managing SCI patients. METHODS: Data on UTIs, bladder management and LOS were obtained from hospital databases and medical records over 26 months. Adherence to staff-administered intermittent catheterisation (staff-IC) was determined from fluid balance charts. RESULTS: Across the cohort (n = 70) UTI rate was 1.1 starts/100 days; UTI by multi-resistant organisms 0.1/100 days. Having ≥1 UTIs compared with none and longer duration of initial urethral indwelling catheterisation (IDC) were associated with longer LOS (p-values < 0.001). For patients with ≥1 UTIs (n = 43/70), longer duration of initial IDC was associated with shorter time to first UTI (1 standard deviation longer [SD, 45.0 days], hazard ratio (HR): 0.7, 95% confidence interval [CI] 0.5-1.0, p-value 0.044). In turn, shorter time to first UTI was associated with higher UTI rate (1 SD shorter [30.7 days], rate ratio (RR): 1.32, 95%CI 1.0-1.7, p-value 0.039). During staff-IC periods (n = 38/70), protocols were followed (85.7% ≤ 6 h apart, 96.1% < 8 h), but 26% of IC volumes exceeded 500 mL; occasional volumes > 800 mL and interruptions requiring temporary IDC were associated with higher UTI rates the following week (odds ratios (ORs): 1.6, 95%CI 1.1-2.3, p-value 0.009; and 3.9, 95%CI 2.6-5.9, p-value < 0.001 respectively). CONCLUSIONS: Reducing initial IDC duration and limiting staff-IC volumes could be investigated to possibly reduce inpatient UTIs and LOS. SPONSORSHIP: None.


Assuntos
Tempo de Internação/estatística & dados numéricos , Traumatismos da Medula Espinal/epidemiologia , Cateterismo Urinário/estatística & dados numéricos , Infecções Urinárias/epidemiologia , Adulto , Cateteres de Demora/estatística & dados numéricos , Humanos , Incidência , Pacientes Internados/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos Retrospectivos , Traumatismos da Medula Espinal/complicações , Fatores de Tempo , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/etiologia , Austrália Ocidental/epidemiologia
5.
J Neurochem ; 149(5): 660-678, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30702755

RESUMO

Following mild traumatic brain injury (mTBI), further mild impacts can exacerbate negative outcomes. To compare chronic damage and deficits following increasing numbers of repeated mTBIs, a closed-head weight-drop model of repeated mTBI was used to deliver 1, 2 or 3 mTBIs to adult female rats at 24 h intervals. Outcomes were assessed at 3 months following the first mTBI. No gross motor, sensory or reflex deficits were identified (p > 0.05), consistent with current literature. Cognitive function assessed using a Morris water maze revealed chronic memory deficits following 1 and 2, but not 3 mTBI compared to shams (p ≤ 0.05). Oxidative damage to DNA was assessed immunohistochemically in the dentate hilus of the hippocampus and splenium of the corpus callosum; no changes were observed. IBA1-positive microglia were increased in size in the cortex following 1 mTBI and in the corpus callosum following 2 mTBI compared to shams (p ≤ 0.05); no changes were observed in the dentate hilus. Glial fibrillary acidic protein (GFAP)-positive astrocyte immunoreactivity was assessed in all three brain regions and no chronic changes were observed. Integrity of myelin ultrastructure in the corpus callosum was assessed using transmission electron microscopy. G ratio was decreased following 2 mTBIs compared to shams (p ≤ 0.05) at post hoc level only. The changing patterns of damage and deficits following increasing numbers of mTBI may reflect dynamic responses to small numbers of mTBIs or a conditioning effect such that increasing numbers of mTBIs do not necessarily result in worsening pathology. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Cover Image for this issue: doi: 10.1111/jnc.14508.


Assuntos
Concussão Encefálica/metabolismo , Concussão Encefálica/patologia , Animais , Concussão Encefálica/etiologia , Feminino , Traumatismos Cranianos Fechados/complicações , Aprendizagem em Labirinto , Transtornos da Memória/etiologia , Ratos
6.
7.
J Neuroinflammation ; 15(1): 201, 2018 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-29981582

RESUMO

BACKGROUND: Following injury to the central nervous system, increased microglia, secretion of pro- and anti-inflammatory cytokines, and altered blood-brain barrier permeability, a hallmark of degeneration, are observed at and immediately adjacent to the injury site. However, few studies investigate how regions remote from the primary injury could also suffer from inflammation and secondary degeneration. METHODS: Adult female Piebald-Viral-Glaxo (PVG) rats underwent partial transection of the right optic nerve, with normal, age-matched, unoperated animals as controls. Perfusion-fixed brains and right optic nerves were harvested for immunohistochemical assessment of inflammatory markers and blood-brain barrier integrity; fresh-frozen brains were used for multiplex cytokine analysis. RESULTS: Immediately ventral to the optic nerve injury, immunointensity of both the pro-inflammatory biomarker inducible nitric oxide synthase (iNOS) and the anti-inflammatory biomarker arginase-1 (Arg1) increased at 7 days post-injury, with colocalization of iNOS and Arg1 immunoreactivity within individual cells. CD11b+ and CD45+ cells were increased 7 days post-injury, with altered BBB permeability still evident at this time. In the lower and middle optic tract and superior colliculus, IBA1+ resident microglia were first increased at 3 days; ED1+ and CD11b+ cells were first increased in the middle and upper tract and superior colliculus 7 days post-injury. Increased fibrinogen immunoreactivity indicative of altered BBB permeability was first observed in the contralateral upper tract at 3 days and middle tract at 7 days post-injury. Multiplex cytokine analysis of brain homogenates indicated significant increases in the pro-inflammatory cytokines, IL-2 and TNFα, and anti-inflammatory cytokine IL-10 1 day post-injury, decreasing to control levels at 3 days for TNFα and 7 days for IL-2. IL-10 was significantly elevated at 1 and 7 days post-injury with a dip at 3 days post-injury. CONCLUSIONS: Partial injury to the optic nerve induces a complex remote inflammatory response, characterized by rapidly increased pro- and anti-inflammatory cytokines in brain homogenates, increased numbers of IBA1+ cells throughout the visual pathways, and increased CD11b+ and ED1+ inflammatory cells, particularly towards the synaptic terminals. BBB permeability can increase prior to inflammatory cell infiltration, dependent on the brain region.


Assuntos
Barreira Hematoencefálica/patologia , Citocinas/metabolismo , Encefalite/etiologia , Traumatismos do Nervo Óptico/complicações , Traumatismos do Nervo Óptico/patologia , Vias Visuais/patologia , Análise de Variância , Animais , Antígenos CD/metabolismo , Barreira Hematoencefálica/fisiopatologia , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Ectodisplasinas/metabolismo , Encefalite/patologia , Feminino , Fibrinogênio/metabolismo , Lateralidade Funcional , Macrófagos/patologia , Proteínas dos Microfilamentos/metabolismo , Microglia/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Nervo Óptico/patologia , Ratos , Fatores de Tempo , Vias Visuais/metabolismo
8.
Muscle Nerve ; 57(1): 100-106, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28214333

RESUMO

INTRODUCTION: We previously have shown that manual stimulation (MS) of vibrissal muscles for 2 months after facial nerve injury in rats improves whisking and reduces motor end plate polyinnervation. Here, we seek to determine whether discontinuing or delaying MS after facial-facial anastomosis (FFA) leads to similar results. METHODS: Rats were subjected to FFA and received MS for (1) 4 months (early and continued), (2) the first but not the last 2 months (discontinued), or (3) the last 2 months (delayed). Intact animals and those not receiving MS (no MS) were also examined. RESULTS: Early and continued MS restored whisking amplitude to 43°, a value significantly higher compared with the discontinued, delayed, and no MS groups (32°, 24°, and 10°, respectively). Motor end plate polyinnervation occurred in all experimental groups but was significantly higher in the delayed group. DISCUSSION: Early and continued MS results in better recovery than when it is either discontinued or delayed. Muscle Nerve 57: 100-106, 2018.


Assuntos
Traumatismos do Nervo Facial/terapia , Estimulação Física , Anastomose Cirúrgica , Animais , Feminino , Placa Motora , Denervação Muscular , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Regeneração Nervosa , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Vibrissas/inervação , Vibrissas/fisiologia
9.
Arch Phys Med Rehabil ; 99(10): 2118-2121, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859181

RESUMO

We examined spinal cord injury (SCI) catheterization practices in Australia to understand practice patterns and consistency with research evidence. A national facilitated discussion forum was held during the annual Australian and New Zealand Spinal Cord Society conference attended by 66 conference delegates. Initially, presentations were given on the latest laboratory research examining bladder changes following SCI; an overview of evidence-based recommendations indicating that intermittent catheterization is best practice; and results of a single-center practice audit that demonstrated substantial delay in transition between acute SCI and intermittent catheterization. The ensuing discussion covered current catheterization practices in both inpatient SCI units and the community and highlighted gaps between evidence and practice, with considerable variation in practice between centers and settings. Reported challenges to implementing best practice included social, economic, and resource factors. A disconnect between hospital and community practice was also identified as an important barrier to long-term uptake of intermittent catheterization following acute SCI. The discussion identified 3 proposed activities: (1) explore current practice and bladder health following SCI in greater depth across SCI units and in local communities through audits and standardized biochemical analysis; (2) determine the behavioral drivers of current practice; and (3) develop a knowledge translation strategy to better align practice with current clinical practice guidelines.


Assuntos
Prática Clínica Baseada em Evidências/tendências , Guias de Prática Clínica como Assunto , Traumatismos da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/terapia , Cateterismo Urinário/métodos , Austrália , Congressos como Assunto , Previsões , Humanos , Nova Zelândia , Traumatismos da Medula Espinal/fisiopatologia , Bexiga Urinária/fisiopatologia
10.
Langmuir ; 33(45): 12926-12933, 2017 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-29022719

RESUMO

The composition of the protein corona formed on poly(ethylene glycol)-functionalized (PEGylated) poly(glycidyl methacrylate) (PGMA) nanoparticles (NPs) was qualitatively and quantitatively compared to the protein corona on non-PEGylated PGMA NPs. Despite the reputation of PEGylated NPs for stealth functionality, we demonstrate the preferential enrichment of specific serum proteins of varied biological function in the protein corona on PEGylated NPs when compared to non-PEGylated NPs. Additionally, we suggest that the base material of polymeric NPs plays a role in the preferential enrichment of select serum proteins to the hard corona.


Assuntos
Nanopartículas , Proteínas Sanguíneas , Polietilenoglicóis , Polímeros , Coroa de Proteína
11.
Exp Brain Res ; 232(6): 2021-33, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24623354

RESUMO

Facial nerve injury is a common clinical trauma involving long-term functional deficits with facial asymmetry leading to associated psychological issues and social hardship. We have recently shown that repair by hypoglossal-facial or facial-facial nerve surgical end-to-end anastomosis and suture [hypoglossal-facial anastomosis (HFA) or facial-facial anastomosis (FFA)] results in collateral axonal branching, polyinnervation of neuromuscular junctions (NMJs) and poor function. We have also shown that another HFA repair procedure using an isogenic Y-tube (HFA + Y-tube) and involving a 10-mm gap reduces collateral axonal branching, but fails to reduce polyinnervation. Furthermore, we have previously demonstrated that manual stimulation (MS) of facial muscles after FFA or HFA reduces polyinnervation of NMJs and improves functional recovery. Here, we examined whether HFA + Y-tube and MS of the vibrissal muscles reduce polyinnervation and restore function. Isogenic Y-tubes were created using abdominal aortas. The proximal hypoglossal nerve was inserted into the long arm and sutured to its wall. The distal zygomatic and buccal facial nerve branches were inserted into the two short arms and likewise sutured to their walls. Manual stimulation involved gentle stroking of the vibrissal muscles by hand mimicking normal whisker movement. We evaluated vibrissal motor performance using video-based motion analysis, degree of collateral axonal branching using double retrograde labeling and the quality of NMJ reinnervation in target musculature using immunohistochemistry. MS after HFA + Y-tube reduced neither collateral branching, nor NMJ polyinnervation. Accordingly, it did not improve recovery of function. We conclude that application of MS after hypoglossal-facial nerve repair using an isogenic Y-tube is contraindicated: it does not lead to functional recovery but, rather, worsens it.


Assuntos
Anastomose Cirúrgica , Nervo Hipoglosso/cirurgia , Manipulações Musculoesqueléticas/métodos , Doenças da Junção Neuromuscular , Recuperação de Função Fisiológica/fisiologia , Vibrissas/inervação , Análise de Variância , Animais , Carbocianinas , Traumatismos do Nervo Facial/complicações , Traumatismos do Nervo Facial/reabilitação , Feminino , Atividade Motora , Doenças da Junção Neuromuscular/etiologia , Doenças da Junção Neuromuscular/reabilitação , Doenças da Junção Neuromuscular/cirurgia , Estimulação Física , Ratos , Ratos Wistar , Procedimentos de Cirurgia Plástica/métodos , Fatores de Tempo , Resultado do Tratamento
13.
Neuron ; 112(12): 1905-1910, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38723637

RESUMO

This NeuroView assesses the interplay among exposome, One Health, and brain capital in health and disease. Physical and social exposomes affect brain health, and green brain skills are required for environmental health strategies. Ibanez et al. address current gaps and strategies needed in research, policy, and technology, offering a road map for stakeholders.


Assuntos
Encéfalo , Expossoma , Humanos , Encéfalo/fisiologia , Saúde Ambiental , Exposição Ambiental/efeitos adversos
14.
J Hazard Mater ; 468: 133803, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377910

RESUMO

Micro and nanosized plastics (MNPs), and a range of associated additive chemicals, have become pervasive contaminants that humans and the environment are exposed to everyday. However, one of the principal challenges in their analysis is adequate strategies to minimise background contamination. Here a blueprint for a specialised plastics and additive-minimised clean room laboratory built for this purpose is presented. Common laboratory construction materials (n = 23) were tested, including acoustic baffles, ceiling materials, floor materials, glazing rubber, and silicone sealant. The % polymer content ranged from 2-76% w/w while the sum concentration of six phthalates ranged from 0.81 (0.73-0.86) to 21000 (15000-27000) mg/kg, assigning many of these materials as inappropriate for use in a clean room environment. The final design of the laboratory consisted of three interconnected rooms, operated under positive pressure with the inner rooms constructed almost entirely of stainless steel. Background concentrations of MNPs and phthalates in the new laboratory were compared to two Physical Containment Level 2 (PC2) laboratory environments, with concentrations of MNPs reduced by > 100 times and phthalates reduced by up to 120 times. This study reports the first known clean room of its kind and provides a blueprint for reference and use by future plastics research.

15.
Neural Regen Res ; 19(12): 2773-2784, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38595294

RESUMO

JOURNAL/nrgr/04.03/01300535-202412000-00032/figure1/v/2024-04-08T165401Z/r/image-tiff For patients with chronic spinal cord injury, the conventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection, pressure sores, osteoporosis, and deep vein thrombosis. Surgery is rarely performed on spinal cord injury in the chronic phase, and few treatments have been proven effective in chronic spinal cord injury patients. Development of effective therapies for chronic spinal cord injury patients is needed. We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal cord injury to compare intensive rehabilitation (weight-bearing walking training) alone with surgical intervention plus intensive rehabilitation. This clinical trial was registered at ClinicalTrials.gov (NCT02663310). The goal of surgical intervention was spinal cord detethering, restoration of cerebrospinal fluid flow, and elimination of residual spinal cord compression. We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement, reduced spasticity, and more rapid bowel and bladder functional recovery than weight-bearing walking training alone. Overall, the surgical procedures and intensive rehabilitation were safe. American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries. Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.

16.
Rev Neurosci ; 24(2): 205-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23492552

RESUMO

Irradiation in the red/near-infrared spectrum (R/NIR, 630-1000 nm) has been used to treat a wide range of clinical conditions, including disorders of the central nervous system (CNS), with several clinical trials currently underway for stroke and macular degeneration. However, R/NIR irradiation therapy (R/NIR-IT) has not been widely adopted in clinical practice for CNS injury or disease for a number of reasons, which include the following. The mechanism/s of action and implications of penetration have not been thoroughly addressed. The large range of treatment intensities, wavelengths and devices that have been assessed make comparisons difficult, and a consensus paradigm for treatment has not yet emerged. Furthermore, the lack of consistent positive outcomes in randomised controlled trials, perhaps due to sub-optimal treatment regimens, has contributed to scepticism. This review provides a balanced précis of outcomes described in the literature regarding treatment modalities and efficacy of R/NIR-IT for injury and disease in the CNS. We have addressed the important issues of specification of treatment parameters, penetration of R/NIR irradiation to CNS tissues and mechanism/s, and provided the necessary detail to demonstrate the potential of R/NIR-IT for the treatment of retinal degeneration, damage to white matter tracts of the CNS, stroke and Parkinson's disease.


Assuntos
Doenças do Sistema Nervoso Central/radioterapia , Sistema Nervoso Central/efeitos da radiação , Raios Infravermelhos/uso terapêutico , Traumatismos do Sistema Nervoso/radioterapia , Humanos
17.
BMC Neurosci ; 14: 98, 2013 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-24011177

RESUMO

BACKGROUND: Traumatic injury to the central nervous system results in damage to tissue beyond the primary injury, termed secondary degeneration. Key events thought to be associated with secondary degeneration involve aspects of mitochondrial function which may be modulated by red/near-infrared irradiation therapy (R/NIR-IT), but precisely how mitochondria are affected in vivo has not been investigated. Secondary degeneration was modelled by transecting the dorsal aspect of the optic nerve in adult rats and mitochondrial ultrastructure in intact ventral optic nerve vulnerable to secondary degeneration investigated with transmission electron microscopy. RESULTS: Despite reported increases in fission following central nervous system injury, we saw no change in mitochondrial densities in optic nerve vulnerable to secondary degeneration in vivo. However, in axons, frequency distributions of mitochondrial profile areas showed higher cumulative probabilities of smaller mitochondrial profiles at day 1 after injury. Glial mitochondrial profiles did not exhibit changes in area, but a more elliptical mitochondrial shape was observed at both day 1 and 7 following injury. Importantly, mitochondrial autophagic profiles were observed at days 1 and 7 in optic nerve vulnerable to secondary degeneration in vivo. Citrate synthase activity was used as an additional measure of mitochondrial mass in ventral optic nerve and was decreased at day 7, whereas mitochondrial aconitase activity increased at day 1 and day 28 after injury in optic nerve vulnerable to secondary degeneration. R/NIR-IT has been used to treat the injured central nervous system, with reported improvements in oxidative metabolism suggesting mitochondrial involvement, but ultrastructural information is lacking. Here we show that R/NIR-IT of injured animals resulted in distributions of mitochondrial areas and shape not significantly different from control and significantly reduced mitochondrial autophagic profiles. R/NIR-IT also resulted in decreased citrate synthase activity (day 7) and increased aconitase activity (day 1) in optic nerve vulnerable to secondary degeneration. CONCLUSIONS: These findings suggest that mitochondrial structure and activity of enzymes of the citric acid cycle are dynamically altered during secondary degeneration in vivo and R/NIR-IT may protect mitochondrial structure.


Assuntos
Raios Infravermelhos , Mitocôndrias/efeitos da radiação , Degeneração Neural/prevenção & controle , Traumatismos do Nervo Óptico/patologia , Nervo Óptico/efeitos da radiação , Animais , Mitocôndrias/ultraestrutura , Degeneração Neural/patologia , Nervo Óptico/ultraestrutura , Ratos
18.
FASEB J ; 26(4): 1593-606, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22223750

RESUMO

Although the organization of neuronal circuitry is shaped by activity patterns, the capacity to modify and/or optimize the structure and function of whole projection pathways using external stimuli is poorly defined. We investigate whether neuronal activity induced by pulsed magnetic fields (PMFs) alters brain structure and function. We delivered low-intensity PMFs to the posterior cranium of awake, unrestrained mice (wild-type and ephrin-A2A5(-/-)) that have disorganized retinocollicular circuitry and associated visuomotor deficits. Control groups of each genotype received sham stimulation. Following daily stimulation for 14 d, we measured biochemical, structural (anterograde tracing), and functional (electrophysiology and behavior) changes in the retinocollicular projection. PMFs induced BDNF, GABA, and nNOS expression in the superior colliculus and retina of wild-type and ephrin-A2A5(-/-) mice. Furthermore, in ephrin-A2A5(-/-) mice, PMFs corrected abnormal neuronal responses and selectively removed inaccurate ectopic axon terminals to improve structural and functional organization of their retinocollicular projection and restore normal visual tracking behavior. In contrast, PMFs did not alter the structure or function of the normal projection in wild-type mice. Sham PMF stimulation had no effect on any mice. Thus, PMF-induced biochemical changes are congruent with its capacity to facilitate beneficial reorganization of abnormal neural circuits without disrupting normal connectivity and function.


Assuntos
Comportamento Animal/fisiologia , Rede Nervosa/anormalidades , Rede Nervosa/fisiologia , Estimulação Magnética Transcraniana/métodos , Vias Visuais/anormalidades , Vias Visuais/fisiologia , Animais , Biomarcadores/metabolismo , Mapeamento Encefálico , Efrina-A2/genética , Efrina-A2/metabolismo , Efrina-A5/genética , Efrina-A5/metabolismo , Humanos , Camundongos , Camundongos Knockout , Rede Nervosa/anatomia & histologia , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Vias Visuais/anatomia & histologia
19.
Org Biomol Chem ; 11(36): 6108-12, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23921718

RESUMO

Amphiphilic calix[4]arenes were designed as phospholipid mimics by incorporating PO3H2 or NMe3(+) head groups. Using PC12 cells and three stressors (H2O2, menadione and glutamate), we established safe calix[4]arene levels that are able not only to deliver antioxidant payloads of curcumin, but intriguingly also have inherent antioxidant properties. The calix[4]arenes appear to be potent synthetic antioxidants that could be used as nano-carriers for drug delivery.


Assuntos
Antioxidantes/química , Calixarenos/química , Sistemas de Liberação de Medicamentos , Micelas , Fenóis/química , Fosfolipídeos/química , Animais , Antioxidantes/síntese química , Antioxidantes/metabolismo , Calixarenos/síntese química , Calixarenos/metabolismo , Ácido Glutâmico/síntese química , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Peróxido de Hidrogênio/síntese química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Estrutura Molecular , Células PC12 , Fenóis/síntese química , Fenóis/metabolismo , Fosfolipídeos/síntese química , Fosfolipídeos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Tensoativos/síntese química , Tensoativos/química , Tensoativos/metabolismo , Vitamina K 3/síntese química , Vitamina K 3/química , Vitamina K 3/metabolismo
20.
J Spinal Cord Med ; 46(5): 830-836, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35792831

RESUMO

CONTEXT/OBJECTIVE: Prevention of urinary tract infection (UTI) after spinal cord injury is an important goal. Intravesical hyaluronic acid with chondroitin sulphate (HA+CS) has been effective in preventing UTI in other settings. We aimed to demonstrate safety and feasibility of a standard treatment course of 7 intravesical HA+CS instillations over 12 weeks, in patients with acute (Arm A) and chronic (Arm B) spinal cord injury (SCI). DESIGN: Follow-up of adverse events, quality of life bladder management difficulty (BMD) and bladder complication (BC) T-scores at baseline (Arm B only), 12 and 24 weeks, and symptomatic urinary tract infection (UTI). RESULTS: Of 33 and 14 individuals screened, 2 and 8 participants were recruited to the study for Arm A and Arm B respectively. Of the 10 participants, 8 completed all 7 instillations. HA+CS commonly caused cloudy urine with urinary sediment which was mild and short-lived. In Arm B, a mean reduction in BMD and BC T-scores was observed from baseline (57.3 and 54.4 respectively), of 6.8 and 4.3 at 12 weeks and 1.6 and 2.8 at 24 weeks, respectively. Four participants with a history of frequent UTI in the prior 12 months did not have UTI in the 24 weeks of the study. CONCLUSIONS: HA+CS was well tolerated. Recruitment was more difficult in early acute SCI; participants with chronic SCI were highly motivated to reduce UTI and manage self-administration without difficulty. Larger case-control or randomized controlled trials in patients with neurogenic bladder from SCI are warranted. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03945110.


Assuntos
Traumatismos da Medula Espinal , Infecções Urinárias , Humanos , Ácido Hialurônico/uso terapêutico , Sulfatos de Condroitina/uso terapêutico , Qualidade de Vida , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Infecções Urinárias/etiologia , Infecções Urinárias/prevenção & controle , Infecções Urinárias/tratamento farmacológico
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