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1.
Epilepsia ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752861

RESUMO

OBJECTIVE: The increased amplitude of ictal activity is a common feature of epileptic seizures, but the determinants of this amplitude have not been identified. Clinically, ictal amplitudes are measured electrographically (using, e.g., electroencephalography, electrocorticography, and depth electrodes), but these methods do not enable the assessment of the activity of individual neurons. Population signal may increase from three potential sources: (1) increased synchrony (i.e., more coactive neurons); (2) altered active state, from bursts of action potentials and/or paroxysmal depolarizing shifts in membrane potential; and (3) altered subthreshold state, which includes all lower levels of activity. Here, we quantify the fraction of ictal signal from each source. METHODS: To identify the cellular determinants of the ictal signal, we measured single cell and population electrical activity and neuronal calcium levels via optical imaging of the genetically encoded calcium indicator (GECI) GCaMP. Spontaneous seizure activity was assessed with microendoscopy in an APP/PS1 mouse with focal cortical injury and via widefield imaging in the organotypic hippocampal slice cultures (OHSCs) model of posttraumatic epilepsy. Single cell calcium signals were linked to a range of electrical activities by performing simultaneous GECI-based calcium imaging and whole-cell patch-clamp recordings in spontaneously seizing OHSCs. Neuronal resolution calcium imaging of spontaneous seizures was then used to quantify the cellular contributions to population-level ictal signal. RESULTS: The seizure onset signal was primarily driven by increased subthreshold activity, consistent with either barrages of excitatory postsynaptic potentials or sustained membrane depolarization. Unsurprisingly, more neurons entered the active state as seizure activity progressed. However, the increasing fraction of active cells was primarily driven by synchronous reactivation and not from continued recruitment of new populations of neurons into the seizure. SIGNIFICANCE: This work provides a critical link between single neuron activity and population measures of seizure activity.

2.
J Virol ; 98(5): e0159623, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38587378

RESUMO

Following acute herpes simplex virus type 2 (HSV-2) infection, the virus undergoes an asymptomatic latent infection of sensory neurons of dorsal root ganglia (DRG). Chemical and physical stress cause intermittent virus reactivation from latently infected DRG and recurrent virus shedding in the genital mucosal epithelium causing genital herpes in symptomatic patients. While T cells appear to play a role in controlling virus reactivation from DRG and reducing the severity of recurrent genital herpes, the mechanisms for recruiting these T cells into DRG and the vaginal mucosa (VM) remain to be fully elucidated. The present study investigates the effect of CXCL9, CXCL10, and CXCL11 T-cell-attracting chemokines on the frequency and function of DRG- and VM-resident CD4+ and CD8+ T cells and its effect on the frequency and severity of recurrent genital herpes in the recurrent herpes guinea pig model. HSV-2 latent-infected guinea pigs were immunized intramuscularly with the HSV-2 ribonucleotide reductase 2 (RR2) protein (Prime) and subsequently treated intravaginally with the neurotropic adeno-associated virus type 8 expressing CXCL9, CXCL10, or CXCL11 chemokines to recruit CD4+ and CD8+ T cells into the infected DRG and VM (Pull). Compared to the RR2 therapeutic vaccine alone, the RR2/CXCL11 prime/pull therapeutic vaccine significantly increased the frequencies of functional tissue-resident and effector memory CD4+ and CD8+ T cells in both DRG and VM tissues. This was associated with less virus in the healed genital mucosal epithelium and reduced frequency and severity of recurrent genital herpes. These findings confirm the role of local DRG- and VM-resident CD4+ and CD8+ T cells in reducing virus shedding at the vaginal site of infection and the severity of recurrent genital herpes and propose the novel prime-pull vaccine strategy to protect against recurrent genital herpes.IMPORTANCEThe present study investigates the novel prime/pull therapeutic vaccine strategy to protect against recurrent genital herpes using the latently infected guinea pig model. In this study, we used the strategy that involves immunization of herpes simplex virus type 2-infected guinea pigs using a recombinantly expressed herpes tegument protein-ribonucleotide reductase 2 (RR2; prime), followed by intravaginal treatment with the neurotropic adeno-associated virus type 8 expressing CXCL9, CXCL10, or CXCL11 T-cell-attracting chemokines to recruit T cells into the infected dorsal root ganglia (DRG) and vaginal mucosa (VM) (pull). We show that the RR2/CXCL11 prime-pull therapeutic vaccine strategy elicited a significant reduction in virus shedding in the vaginal mucosa and decreased the severity and frequency of recurrent genital herpes. This protection was associated with increased frequencies of functional tissue-resident (TRM cells) and effector (TEM cells) memory CD4+ and CD8+ T cells infiltrating latently infected DRG tissues and the healed regions of the vaginal mucosa. These findings shed light on the role of tissue-resident and effector memory CD4+ and CD8+ T cells in DRG tissues and the VM in protection against recurrent genital herpes and propose the prime-pull therapeutic vaccine strategy in combating genital herpes.


Assuntos
Quimiocina CXCL11 , Herpes Genital , Herpesvirus Humano 2 , Ribonucleotídeo Redutases , Animais , Feminino , Cobaias , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiocina CXCL11/imunologia , Quimiocina CXCL11/metabolismo , Modelos Animais de Doenças , Gânglios Espinais/imunologia , Gânglios Espinais/virologia , Herpes Genital/imunologia , Herpes Genital/prevenção & controle , Herpesvirus Humano 2/imunologia , Células T de Memória/imunologia , Ribonucleotídeo Redutases/metabolismo , Vacinação , Vagina/virologia , Vagina/imunologia
3.
BMJ Open ; 13(10): e069681, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37827733

RESUMO

OBJECTIVES: To investigate factors concerning patients regarding biological/target synthetic disease-modifying antirheumatic drugs (b/ts DMARDs) in treating inflammatory arthritis (IA). DESIGN: This study consists of a systematic review and a cross-sectional survey in Hong Kong. A systematic review of literature following Preferred Reporting Items for Systematic Reviews and Meta-Analyses was conducted on PubMed, Web of Science, Cochrane and Embase between 1 January 2000 and 1 January 2022. Content analysis was conducted to summarise factors grouped by four themes-social aspects (SA), clinical aspects (CA), medicine characteristics (MC) and financial aspects (FA) in the decision-making process. One cross-sectional survey among Hong Kong patients with IA was conducted to add to global evidence. SETTING: A systematic review of global evidence and a patient-based survey in Hong Kong to complement scarce evidence in Asia regions. RESULTS: The systematic review resulted in 34 studies. The four themes were presented in descending order consistently but varied with frequency throughout decision-making processes. During decision-making involving medication initiation, preference and discontinuation, MC (reported frequency: 83%, 86%, 78%), SA (56%, 43%, 78%) and FA (39%, 33%, 56%) were the three most frequently reported factors, whereas CA was less studied. Local survey also revealed that MC factors such as treatment efficacy and the probability of severe adverse events, and SA factors such as the availability of government or charity subsidy, influenced patients' initiation and preference for b/ts DMARDs. Meanwhile, self-estimated improvement in disease conditions (SA), drug side effects (MC) and drug costs (FA) were associated with treatment discontinuation. CONCLUSIONS: Global and local evidence consistently indicate that MC and SA are important considerations in patients' decisions regarding novel DMARDs. Health policies that reduce patients' financial burden and enhances healthcare professionals' engagement in decision-making and treatment delivery should be in place with an efficient healthcare system for managing IA optimistically.


Assuntos
Antirreumáticos , Artrite , Humanos , Antirreumáticos/uso terapêutico , Hong Kong , Estudos Transversais , Resultado do Tratamento
4.
bioRxiv ; 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37609157

RESUMO

Following acute herpes simplex virus type 2 (HSV-2) infection, the virus undergoes latency in sensory neurons of the dorsal root ganglia (DRG). Intermittent virus reactivation from latency and shedding in the vaginal mucosa (VM) causes recurrent genital herpes. While T-cells appear to play a role in controlling virus reactivation and reducing the severity of recurrent genital herpes, the mechanisms for recruiting these T-cells into DRG and VM tissues remain to be fully elucidated. The present study investigates the effect of CXCL9, CXCL10, and CXCL11 T-cell-attracting chemokines on the frequency and function of DRG- and VM-resident CD4+ and CD8+ T cells and its effect on the frequency and severity of recurrent genital herpes. HSV-2 latent-infected guinea pigs were immunized intramuscularly with the HSV-1 RR2 protein (Prime) and subsequently treated intravaginally with the neurotropic adeno-associated virus type 8 (AAV-8) expressing CXCL9, CXCL10, or CXCL11 T-cell-attracting chemokines (Pull). Compared to the RR2 therapeutic vaccine alone, the RR2/CXCL11 prime/pull therapeutic vaccine significantly increased the frequencies of functional tissue-resident (TRM cells) and effector (TEM cells) memory CD4+ and CD8+ T cells in both DRG and VM tissues. This was associated with less virus shedding in the healed genital mucosal epithelium and reduced frequency and severity of recurrent genital herpes. These findings confirm the role of local DRG- and VM-resident CD4+ and CD8+ TRM and TEM cells in reducing virus reactivation shedding and the severity of recurrent genital herpes and propose the novel prime/pull vaccine strategy to protect against recurrent genital herpes.

5.
Epilepsy Curr ; 23(2): 127-129, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122404
6.
Lancet Reg Health West Pac ; 22: 100426, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35637863

RESUMO

Background: Few studies investigated the mechanisms of treatment-resistant depression (TRD) leading to the worsened survival outcome, and economic evidence was mostly restricted to short follow-ups. We aimed to examine the association and potential mediators between TRD and all-cause mortality, and estimate a longer-term associated health resource utilisation pattern. Methods: This was a population-based cohort study using territory-wide electronic medical records in Hong Kong. Incident depression patients diagnosed in 2014 were followed up from the first diagnosis to death or December 2019 for TRD identification. We matched the TRD cohort 1:4 to the non-TRD cohort on propensity scores estimated by age, sex, history of physical disorders, and history of psychiatric conditions before depression diagnoses. Findings: 18% of incident patients developed TRD within six years of follow-up. Cox model showed that patients with TRD had 1⋅52-fold (95% CI: 1⋅14-2⋅02) greater risk of all-cause mortality, compared with non-TRD patients. Path analysis suggested that post-TRD psychiatric conditions significantly mediated 41⋅6% of mortality in patients with TRD (p=0.003). TRD was associated with 1⋅8-fold (95%CI: 1⋅63-2⋅00) higher healthcare costs compared to non-TRD patients over six years in negative binomial regression, with higher costs for both psychiatric and non-psychiatric services utilisation in all settings. Interpretation: Identifying patients with TRD and subsequent monitoring for post-TRD psychiatric diagnoses could be a way to reduce premature mortality. Multidisciplinary care involving both psychiatric and general medical professionals is also warranted to relieve the multifaceted impacts on healthcare resources and overall cost. Funding: Unconditional educational grant from Janssen.

7.
Vaccine ; 40(10): 1390-1396, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35140013

RESUMO

OBJECTIVE: CoronaVac (Sinovac) Covid-19 vaccine has recently been approved for emergency use by the World Health Organization. However, data on its reactogenicity in real-world settings is scant. This study aimed to compare self-reported post-vaccination adverse reactions between CoronaVac and Comirnaty (Pfizer-BioNTech). METHODS: We adopted a prospective cohort study design using online surveys from the day of first-dose vaccination with intensive follow-up through two weeks after the second dose (11 time points). The primary outcome was adverse reactions (any versus none) and secondary outcomes were the sub-categories of adverse reactions (local, systemic, and severe allergic reactions). Potential effect modification across multimorbidity status, older age, and sex was examined. RESULTS: In total, 2,098 participants who were scheduled to complete the 14th-day survey were included, with 46.2% receiving Comirnaty. Retention rate two weeks after the second dose was 81.0% for the CoronaVac group and 83.6% for the Comirnaty group. Throughout the follow-up period, 801 (82.7%) of those receiving Comirnaty and 543 (48.1%) of those receiving CoronaVac reported adverse reactions. Adjusted analysis suggested that compared with Comirnaty, CoronaVac was associated with 83%-reduced odds of any adverse reactions [adjusted odds ratio (AOR) = 0.17, 95% confidence interval (CI) 0.15-0.20], 92%-reduced odds of local adverse reactions (AOR = 0.08, 95% CI 0.06-0.09), and 76%-reduced odds of systemic adverse reactions (AOR = 0.24, 95% CI 0.16-0.28). No significant effect modification was identified. CONCLUSION: This post-marketing study comparing the reactogenicity of Covid-19 vaccines suggests a lower risk of self-reported adverse reactions following vaccination with CoronaVac compared with Comirnaty.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Estudos Prospectivos , SARS-CoV-2 , Autorrelato
8.
Orphanet J Rare Dis ; 17(1): 3, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983612

RESUMO

BACKGROUND: Information about the specific regulatory environment of orphan drugs is scarce and inconsistent. Uncertainties surrounding the postmarketing long-term safety of orphan drugs remain. This study aimed to evaluate the labelling changes of orphan drugs and to identify postmarketing safety-associated approval factors. METHODS: This retrospective cohort study includes all drugs with orphan drug designation approved by the Center for Drug Evaluation and Research of the US Food and Drug Administration between 1999 and 2018. Main outcomes are safety-related labelling changes up to 31 December 2019. We defined any safety-related labelling changes as postmarketing safety events (PMSE). Safety-related withdrawals, suspensions, and boxed warnings were further categorised as severe postmarketing safety events (SPSE). Outcome measurements include frequencies of PMSE, SPSE, and association between approval factors and the occurrence of safety events. RESULTS: Amongst the 214 drugs identified with orphan drug designation (25.7% biologics), 83.6% were approved through at least one expedited programme, and 29.4% were approved with boxed warnings. During a median follow-up of 6.74 years since approval, 69.2% and 14.5% of the analysed orphan drugs had PMSE and SPSE, respectively. Safety-related withdrawal (0%, 0/214), suspended marketing (0.46%, 1/214) and new boxed warnings are uncommon (3.7%, 8/214). The safety-related labelling changes were more frequent in the drugs approved with boxed warnings [Incidence rate ratio (IRR): 1.95 (1.02-3.73)] and approved for long-term use [IRR: 2.76 (1.52-5.00)]. CONCLUSIONS AND RELEVANCE: In this long-term postmarketing analysis, approximately 70% of FDA-approved orphan drugs had safety-related labelling changes although severe safety events were rare. While maintaining early access to orphan drugs, the drug regulatory body has taken timely regulatory action with postmarketing surveillance to ensure patient safety.


Assuntos
Aprovação de Drogas , Produção de Droga sem Interesse Comercial , Humanos , Vigilância de Produtos Comercializados , Estudos Retrospectivos , Estados Unidos , United States Food and Drug Administration
9.
Int J Infect Dis ; 116: 47-50, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34965462

RESUMO

OBJECTIVES: Although clinical data have shown that the BNT162b2 vaccine, which is widely used in many countries, is safe and effective as a protection against the SARS-CoV-2 infection, extant research in adverse reactions using real-world data of various sociodemographic characteristics is scant. METHODS: We conducted a prospective cohort study to compare age differences in self-reported reactogenicity of BNT162b2 in Hong Kong. A total of 1,516 participants were intensively followed up for two weeks following both doses of BNT162b2 vaccination, during which their basic demographic, health conditions, and medication information were collected. RESULTS: Results from the generalized mixed model showed that compared with adults aged 18 to 59 years, older adults aged 60 years or above had a lower risk of adverse reactions and adolescents aged 12 to 17 years had a moderately higher risk. CONCLUSIONS: Results of this study should be informative to parents considering BNT162b2 vaccination for their children in that moderately increased reactogenicity compared with adults is anticipated.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Adulto , Idoso , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Criança , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Mensageiro , SARS-CoV-2 , Autorrelato , Adulto Jovem
10.
Brain ; 145(2): 531-541, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-34431994

RESUMO

Seizure initiation is the least understood and most disabling element of epilepsy. Studies of ictogenesis require high speed recordings at cellular resolution in the area of seizure onset. However, in vivo seizure onset areas cannot be determined at the level of resolution necessary to enable such studies. To circumvent these challenges, we used novel GCaMP7-based calcium imaging in the organotypic hippocampal slice culture model of post-traumatic epilepsy in mice. Organotypic hippocampal slice cultures generate spontaneous, recurrent seizures in a preparation in which it is feasible to image the activity of the entire network (with no unseen inputs existing). Chronic calcium imaging of the entire hippocampal network, with paired electrophysiology, revealed three patterns of seizure onset: (i) low amplitude fast activity; (ii) sentinel spike; and (iii) spike burst and low amplitude fast activity onset. These patterns recapitulate common features of human seizure onset, including low voltage fast activity and spike discharges. Weeks-long imaging of seizure activity showed a characteristic evolution in onset type and a refinement of the seizure onset zone. Longitudinal tracking of individual neurons revealed that seizure onset is stochastic at the single neuron level, suggesting that seizure initiation activates neurons in non-stereotyped sequences seizure to seizure. This study demonstrates for the first time that transitions to seizure are not initiated by a small number of neuronal 'bad actors' (such as overly connected hub cells), but rather by network changes which enable the onset of pathology among large populations of neurons.


Assuntos
Cálcio , Epilepsia , Animais , Eletroencefalografia , Hipocampo , Humanos , Camundongos , Neurônios/fisiologia , Convulsões
11.
Vaccine ; 39(19): 2628-2635, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33858719

RESUMO

BACKGROUND: Nine years after the introduction of pneumococcal conjugate vaccine (PCV) in the United States, Hong Kong (HK) introduced the vaccine to its universal childhood immunisation programme in 2009. We aimed to assess the impact of childhood PCV immunisation on all-cause pneumonia (ACP) admissions among the overall population of HK. METHODS: In this population-based interrupted time series analysis, we used territory-wide population-representative electronic health records in HK to evaluate the vaccine impact. We identified hospitalised patients with a diagnosis of pneumonia from any cause between 2004 and 2017. We applied segmented Poisson regression to assess the gradual change in the monthly incidence of ACP admissions between pre- and post-vaccination periods. Negative outcome control, subgroup and sensitivity analyses were used to test the robustness of the main analysis. FINDINGS: Over the 14-year study period, a total of 587,607 ACP episodes were identified among 357,950 patients. The monthly age-standardised incidence of ACP fluctuated between 33.42 and 87.44 per 100,000-persons. There was a marginal decreasing trend in pneumonia admissions after PCV introduction among overall population (incidence rate ratio [IRR]: 0·9965, 95% confidence interval [CI]: 0·9932-0·9998), and older adults (≥65 years, IRR: 0·9928, 95% CI: 0·9904-0·9953) but not in younger age groups. INTERPRETATION: There was a marginally declining trend of overall ACP admissions in HK up to eight years after childhood PCV introduction. The significance disappeared when fitting sensitivity analyses. The results indicate the complexities of using non-specific endpoints for measuring vaccine effect and the necessity of enhancing serotype surveillance systems for replacement monitoring. FUNDING: Health and Medical Research Fund, Food and Health Bureau of the Government of Hong Kong (Reference number: 18171272).


Assuntos
Infecções Pneumocócicas , Pneumonia Pneumocócica , Idoso , Hong Kong/epidemiologia , Humanos , Lactente , Análise de Séries Temporais Interrompida , Vacinas Pneumocócicas , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/prevenção & controle , Vacinas Conjugadas
12.
J Neurosci ; 39(19): 3611-3626, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30846615

RESUMO

Developing cortical GABAergic interneurons rely on genetic programs, neuronal activity, and environmental cues to construct inhibitory circuits during early postnatal development. Disruption of these events can cause long-term changes in cortical inhibition and may be involved in neurological disorders associated with inhibitory circuit dysfunction. We hypothesized that tonic glutamate signaling in the neonatal cortex contributes to, and is necessary for, the maturation of cortical interneurons. To test this hypothesis, we used mice of both sexes to quantify extracellular glutamate concentrations in the cortex during development, measure ambient glutamate-mediated activation of developing cortical interneurons, and manipulate tonic glutamate signaling using subtype-specific NMDA receptor antagonists in vitro and in vivo We report that ambient glutamate levels are high (≈100 nm) in the neonatal cortex and decrease (to ≈50 nm) during the first weeks of life, coincident with increases in astrocytic glutamate uptake. Consistent with elevated ambient glutamate, putative parvalbumin-positive interneurons in the cortex (identified using G42:GAD1-eGFP reporter mice) exhibit a transient, tonic NMDA current at the end of the first postnatal week. GluN2C/GluN2D-containing NMDA receptors mediate the majority of this current and contribute to the resting membrane potential and intrinsic properties of developing putative parvalbumin interneurons. Pharmacological blockade of GluN2C/GluN2D-containing NMDA receptors in vivo during the period of tonic interneuron activation, but not later, leads to lasting decreases in interneuron morphological complexity and causes deficits in cortical inhibition later in life. These results demonstrate that dynamic ambient glutamate signaling contributes to cortical interneuron maturation via tonic activation of GluN2C/GluN2D-containing NMDA receptors.SIGNIFICANCE STATEMENT Inhibitory GABAergic interneurons make up 20% of cortical neurons and are critical to controlling cortical network activity. Dysfunction of cortical inhibition is associated with multiple neurological disorders, including epilepsy. Establishing inhibitory cortical networks requires in utero proliferation, differentiation, and migration of immature GABAergic interneurons, and subsequent postnatal morphological maturation and circuit integration. Here, we demonstrate that ambient glutamate provides tonic activation of immature, putative parvalbumin-positive GABAergic interneurons in the neonatal cortex via high-affinity NMDA receptors. When this activation is blocked, GABAergic interneuron maturation is disrupted, and cortical networks exhibit lasting abnormal hyperexcitability. We conclude that temporally precise activation of developing cortical interneurons by ambient glutamate is critically important for establishing normal cortical inhibition.


Assuntos
Ácido Glutâmico/metabolismo , Interneurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Córtex Sensório-Motor/metabolismo , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Feminino , Interneurônios/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Córtex Sensório-Motor/efeitos dos fármacos
13.
eNeuro ; 4(5)2017.
Artigo em Inglês | MEDLINE | ID: mdl-29109971

RESUMO

Developmental cortical malformations (DCMs) result from pre- and perinatal insults, as well as genetic mutations. Hypoxia, viral infection, and traumatic injury are the most common environmental causes of DCMs, and are associated with the subsyndromes focal polymicrogyria and focal cortical dysplasia (FCD) Type IIId, both of which have a high incidence of epilepsy. Understanding the molecular signals that lead to the formation of a hyperexcitable network in DCMs is critical to devising novel treatment strategies. In a previous study using the freeze-lesion (FL) murine model of DCM, we found that levels of thrombospondin (TSP) and the calcium channel auxiliary subunit α2δ-1 were elevated. TSP binds to α2δ-1 to drive the formation of excitatory synapses during development, suggesting that overactivation of this pathway may lead to exuberant excitatory synaptogenesis and network hyperexcitability seen in DCMs. In that study, antagonizing TSP/α2δ-1 signaling using the drug gabapentin (GBP) reduced many FL-induced pathologies. Here, we used mice with a genetic deletion of α2δ-1 to determine how α2δ-1 contributes to cell death, elevated excitatory synapse number, and in vitro network function after FL and to examine the molecular specificity of GBP's effects. We identified a critical role for α2δ-1 in FL-induced pathologies and in mediating the neuroprotective effects of GBP. Interestingly, genetic deletion of α2δ-1 did not eliminate GBP's effects on synaptogenesis, suggesting that GBP can have α2δ-1-independent effects. Taken together these studies suggests that inhibiting α2δ-1 signaling may have therapeutic promise to reduce cell death and network reorganization associated with insult-induced DCMs.


Assuntos
Aminas/farmacologia , Canais de Cálcio/metabolismo , Ácidos Cicloexanocarboxílicos/farmacologia , Malformações do Desenvolvimento Cortical/metabolismo , Neurônios/metabolismo , Neuroproteção/fisiologia , Fármacos Neuroprotetores/farmacologia , Ácido gama-Aminobutírico/farmacologia , Animais , Canais de Cálcio/deficiência , Canais de Cálcio/genética , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Modelos Animais de Doenças , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Congelamento , Gabapentina , Masculino , Malformações do Desenvolvimento Cortical/tratamento farmacológico , Malformações do Desenvolvimento Cortical/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Potenciais Pós-Sinápticos em Miniatura/efeitos dos fármacos , Potenciais Pós-Sinápticos em Miniatura/fisiologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neuroproteção/efeitos dos fármacos , Córtex Somatossensorial/anormalidades , Córtex Somatossensorial/efeitos dos fármacos , Córtex Somatossensorial/crescimento & desenvolvimento , Córtex Somatossensorial/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/patologia , Técnicas de Cultura de Tecidos
14.
Immunology ; 152(4): 589-601, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28742222

RESUMO

Seizures are due to excessive, synchronous neuronal firing in the brain and are characteristic of epilepsy, the fourth most prevalent neurological disease. We report handling-induced and spontaneous seizures in mice deficient for CD39, a cell-surface ATPase highly expressed on microglial cells. CD39-/- mice with handling-induced seizures had normal input-output curves and paired-pulse ratio measured from hippocampal slices and lacked microgliosis, astrogliosis or overt cell loss in the hippocampus and cortex. As expected, however, the cerebrospinal fluid of CD39-/- mice contained increased levels of ATP and decreased levels of adenosine. To determine if immune activation was involved in seizure progression, we challenged mice with lipopolysaccharide (LPS) and measured the effect on microglia activation and seizure severity. Systemic LPS challenge resulted in increased cortical staining of Iba1/CD68 and gene array data from purified microglia predicted increased expression of interleukin-8, triggering receptor expressed on myeloid cells 1, p38, pattern recognition receptors, death receptor, nuclear factor-κB , complement, acute phase, and interleukin-6 signalling pathways in CD39-/- versus CD39+/+ mice. However, LPS treatment did not affect handling-induced seizures. In addition, microglia-specific CD39 deletion in adult mice was not sufficient to cause seizures, suggesting instead that altered expression of CD39 during development or on non-microglial cells such as vascular endothelial cells may promote the seizure phenotype. In summary, we show a correlation between altered extracellular ATP/adenosine ratio and a previously unreported seizure phenotype in CD39-/- mice. This work provides groundwork for further elucidation of the underlying mechanisms of epilepsy.


Assuntos
Trifosfato de Adenosina/imunologia , Adenosina/imunologia , Apirase/deficiência , Córtex Cerebral/imunologia , Hipocampo/imunologia , Convulsões/imunologia , Adenosina/genética , Trifosfato de Adenosina/genética , Animais , Antígenos CD/imunologia , Apirase/imunologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/imunologia , Córtex Cerebral/patologia , Hipocampo/patologia , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/imunologia , Convulsões/genética , Convulsões/patologia
15.
Neurobiol Dis ; 98: 149-157, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27852007

RESUMO

Infantile spasms (IS) are a catastrophic childhood epilepsy syndrome characterized by flexion-extension spasms during infancy that progress to chronic seizures and cognitive deficits in later life. The molecular causes of IS are poorly defined. Genetic screens of individuals with IS have identified multiple risk genes, several of which are predicted to alter ß-catenin pathways. However, evidence linking malfunction of ß-catenin pathways and IS is lacking. Here, we show that conditional deletion in mice of the adenomatous polyposis coli gene (APC cKO), the major negative regulator of ß-catenin, leads to excessive ß-catenin levels and multiple salient features of human IS. Compared with wild-type littermates, neonatal APC cKO mice exhibit flexion-extension motor spasms and abnormal high-amplitude electroencephalographic discharges. Additionally, the frequency of excitatory postsynaptic currents is increased in layer V pyramidal cells, the major output neurons of the cerebral cortex. At adult ages, APC cKOs display spontaneous electroclinical seizures. These data provide the first evidence that malfunctions of APC/ß-catenin pathways cause pathophysiological changes consistent with IS. Our findings demonstrate that the APC cKO is a new genetic model of IS, provide novel insights into molecular and functional alterations that can lead to IS, and suggest novel targets for therapeutic intervention.


Assuntos
Proteína da Polipose Adenomatosa do Colo/deficiência , Modelos Animais de Doenças , Neurônios/metabolismo , Convulsões/metabolismo , Espasmos Infantis/metabolismo , beta Catenina/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Animais Recém-Nascidos , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Eletroencefalografia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Humanos , Lactente , Masculino , Camundongos Knockout , Movimento/fisiologia , Neurônios/patologia , Fenótipo , Convulsões/patologia , Transdução de Sinais , Espasmos Infantis/patologia , Técnicas de Cultura de Tecidos
16.
Hong Kong J Occup Ther ; 28(1): 15-23, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30186063

RESUMO

OBJECTIVE/BACKGROUND: Employed breast cancer survivors (BCS) may experience residual symptoms that can impact their work productivity and quality of life (QoL), but it is unclear whether such associations exist among BCS in Hong Kong. Therefore, this study was designed to explore the symptom burden (cognitive limitation and psychological distress) of employed BCS in HK, and to investigate whether such factors are related to work productivity and QoL. METHODS: A cross-sectional study including employed BCS (n = 30), women with musculoskeletal conditions (n = 30), and healthy women (n = 30) was conducted. Participants completed a questionnaire covering their sociodemographics, the Hospital Anxiety and Depression Scale, Cognitive Symptom Checklist, Work Limitation Questionnaire, and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30. RESULTS: The self-perceived cognitive limitations at work of BCS were significantly higher than that of the healthy control group (5.33 vs. 2.60; p < .05). The cognitive limitations in BCS were significantly associated with their QoL (ß = -0.320; p = .032). A negative relationship between depression and QoL in BCS was also observed in this study. CONCLUSION: This exploratory study provides local evidence that BCS experience greater work-task related cognitive limitations and that is related to QoL. Similar to findings in other countries, this provides insight for the consideration of early identification of cognitive problems in this particular patient group. Further studies may be needed to further substantiate such findings and to examine the effectiveness of potential cognitive interventions.

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