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1.
Semin Arthritis Rheum ; 65: 152380, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281467

RESUMO

BACKGROUND: The Outcome Measures in Rheumatology (OMERACT) Systemic Lupus Erythematosus (SLE) Working Group held a Special Interest Group (SIG) at the OMERACT 2023 conference in Colorado Springs where SLE collaborators reviewed domain sub-themes generated through qualitative research and literature review. OBJECTIVE: The objective of the SIG and the subsequent meetings of the SLE Working Group was to begin the winnowing and binning of candidate domain sub-themes into a preliminary list of candidate domains that will proceed to the consensus Delphi exercise for the SLE COS. METHODS: Four breakout groups at the SLE SIG in Colorado Springs winnowed and binned 132 domain sub-themes into candidate domains, which was continued with a series of virtual meetings by an advisory group of SLE patient research partners (PRPs), members of the OMERACT SLE Working Group Steering Committee, and other collaborators. RESULTS: The 132 domain sub-themes were reduced to a preliminary list of 20 candidate domains based on their clinical and research relevance for clinical trials and research studies. CONCLUSION: A meaningful and substantial winnowing and binning of candidate domains for the SLE COS was achieved resulting in a preliminary list of 20 candidate domains.


Assuntos
Lúpus Eritematoso Sistêmico , Reumatologia , Humanos , Opinião Pública , Avaliação de Resultados em Cuidados de Saúde , Lúpus Eritematoso Sistêmico/terapia , Consenso
2.
Arch Dis Child ; 109(4): 292-296, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-37973197

RESUMO

BACKGROUND: The West Midlands Newborn Bloodspot Screening Laboratory is one of 16 in the UK and serves two tertiary paediatric cystic fibrosis (CF) centres (Staffordshire Children's Hospital at Royal Stoke and Birmingham Children's Hospital). CF newborn bloodspot screening (NBS) in this region started in November 2006 prior to the UK national roll-out in 2007. It uses an immunoreactive trypsinogen (IRT)/DNA/IRT protocol. We report the outcomes from 15 years of CF screening. METHODS: The West Midlands CF NBS outcomes from 1 November 2006 to 31 October 2021 were reviewed. Clinical data were also obtained for babies referred to the CF centres as 'CF suspected'. RESULTS: 1 075 161 babies were screened, with 402 referred as 'CF suspected' and 205 identified as CF carriers. Of the 'CF suspected' babies, 268 were diagnosed with CF, 33 with CF screen positive, inconclusive diagnosis (CFSPID) and 17 as a CF carrier. Any CF-related diagnosis was excluded in 67. Outcome data were not available for 17, of whom 14 had died. Eighteen children with a negative CF NBS have subsequently been diagnosed with CF, 10 had meconium ileus and 8 were true 'affected not detected', presenting with respiratory symptoms or failure to thrive. This gives the West Midlands a CF birth prevalence of 1 in 4012 live births and the NBS protocol a sensitivity of 97.1% and a positive predictive value of 66.7%. CONCLUSIONS: This large regional data set has excellent case ascertainment and demonstrates successful performance of the CF NBS protocol, with low numbers identified as CFSPID or CF carriers.


Assuntos
Fibrose Cística , Lactente , Recém-Nascido , Humanos , Criança , Fibrose Cística/diagnóstico , Fibrose Cística/epidemiologia , Fibrose Cística/genética , Triagem Neonatal/métodos , Testes Genéticos/métodos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Tripsinogênio , Reino Unido/epidemiologia
3.
Respir Med ; 201: 106937, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35926429

RESUMO

BACKGROUND: Non cystic fibrosis, non primary ciliary dyskinesia bronchiectasis (nCFnPCD-BE) results in significant morbidity with few evidence-based treatments. OBJECTIVE: assessments are required to assess severity and evaluate treatment. Lung clearance index (LCI) measures ventilation inhomogeneity and is a sensitive test of disease in CF; its use in nCFnPCD-BE is unclear. METHODS: A systematic review of LCI in nCFnPCD-BE was performed using standard methodology (protocol registered on PROSPERO, University of York). RESULTS: Of 276 records identified, 12 articles, describing 519 adult and paediatric patients in cross-sectional studies were included, addressing several domains. 1: What is the utility of LCI in detecting disease and severity? LCI detected disease in adults, differentiating bronchiectasis from controls (AUC 0.90 to 0.96) and mild from moderate/severe bronchiectasis on CT (AUC 0.73). 2: Does LCI correlate with spirometry and imaging? LCI correlated with spirometry in adult (r = -0.37 to -0.61) and paediatric (r = -0.6) groups, signs of bronchiectasis on CT, and CT scoring systems (modified Reiff). 3: Does LCI relate to subjective scores of severity? In adults, LCI correlated with St. George's Respiratory Questionnaire (r = 0.18) and Bronchiectasis Severity Index (r = 0.45). 4: Does LCI identify response to intervention? LCI did not change in studies examining LCI pre-post intervention (adults treated for exacerbation and undergoing physiotherapy). Overall study quality was variable. CONCLUSION: Contrary to data in CF, the review did not identify good quality studies defining the role of LCI in children with bronchiectasis. In adults, LCI was a sensitive measure of disease severity and correlated with clinical assessment tools.


Assuntos
Bronquiectasia , Transtornos da Motilidade Ciliar , Adulto , Bronquiectasia/diagnóstico por imagem , Bronquiectasia/patologia , Criança , Estudos Transversais , Fibrose , Volume Expiratório Forçado/fisiologia , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia
4.
Am J Ophthalmol Case Rep ; 27: 101621, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35782169

RESUMO

Purpose: Open-air motor vehicles present unique trauma risks to the eyes and face. We describe two patients who suffered a crash while riding an all-terrain vehicle (ATV), leading to globe dislocation with optic nerve avulsion in order to raise awareness about the risks associated with ATV accidents. Observations: In both cases, the injury was caused by high-speed trauma to the orbit involving a tree branch. One patient sustained a life threatening arrythmia requiring a short stay in the intensive care unit, and both patients required emergent surgical management and eventual socket reconstruction. Conclusions and Importance: These cases highlight the need for greater advocacy on behalf of rider safety. The authors encourage ophthalmologists to counsel patients who use ATVs to wear helmets, seatbelts, and protective eyewear to prevent these types of injuries in the future.

5.
Respir Med ; 199: 106878, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35633605

RESUMO

BACKGROUND: The availability of mutation-specific cystic fibrosis modulator therapies has the potential to improve the lives of children and adults with cystic fibrosis. The frequency of mutations causing defects in the cystic fibrosis transmembrane conductance regulator (CFTR) function varies between sub-groups in multi-ethnic populations. The profile of patients eligible for CFTR modulator ivacaftor/tezacaftor/elexacaftor (Kaftrio™) therapy based on ethnicity has not been reported in the United Kingdom CF population. METHODS: We conducted a descriptive cross-sectional analysis of patients in the UK CF Registry who had annual review data submissions in 2019. Data analysed included demographic characteristics, spirometry, chronic Pseudomonas status, nutrition, and CF related diabetes status. The genotype data was stratified by whether there was at least one copy of F508del or no copy of F508del as current eligibility for ivacaftor/tezacaftor/elexacaftor, or projected future eligibility, is defined as having at least one copy of F508del mutation. RESULTS: Data from 9887 patients were reviewed, 46.7% female, mean age 22.5 years. 8.6% (n = 852) patients had no copy of F508del making them ineligible for ivacaftor/tezacaftor/elexacaftor. Overall, 93.4% of patients were of white ethnicity, with a similar proportion of those with at least one F508del being white (95.6%). This was reduced to 70.0% of those with no F508del. The proportion of people of Asian ethnicity was much higher in the no F508del group (19.2% vs 1.2%). Compared with one F508del patients, the no F508del group were older (25.2 years vs 22.2 years, p < 0.001), had higher prevalence of pancreatic sufficiency (39.0% vs 14.9% p < 0.001), lower prevalence of chronic Pseudomonas infection (21.1% vs. 26.6%, p < 0.001), and higher best FEV1 from the previous year (proportion with greater than 70% FEV1 predicted, 66.1% vs 63.0%, p = 0.005). CONCLUSION: Patients from black, Asian and minority ethnic backgrounds are significantly less likely to be eligible for ivacaftor/tezacaftor/elexacaftor based on the current prescribing policy in the UK. At present this is the most highly effective CF modulator therapy available to treat people with CF. The CF community should urgently address the unmet need for effective targeted therapies for patients without F508del.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Adulto , Criança , Estudos Transversais , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Feminino , Humanos , Masculino , Mutação , Testes de Função Respiratória , Adulto Jovem
7.
Cell Surf ; 7: 100064, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34703957

RESUMO

Infections resulting from Mycobacterium abscessus are increasing in prevalence worldwide, with the greatest risk posed to patients with underlying respiratory conditions. Treatment for infections is difficult due to wide ranging intrinsic antimicrobial resistance, which is compounded by the existence of a range of subspecies within the M. abscessus complex, each with varying additional antimicrobial resistance profiles. Previously, the use of ß-lactam/ß-lactamase inhibitors within a combination therapy has been proposed as an effective treatment option for pulmonary M. abscessus infections. Here, we assess the in vitro efficacy of two non-ß-lactam based inhibitors, relebactam and avibactam, as agents against M. abscessus with their respective partner drugs imipenem and ceftazidime, as well as in triplicate combinations with additional ß-lactam antibiotics against the M. abscessus complex. We have shown that the commercially available ratio of imipenem to relebactam is the appropriate ratio for bactericidal activity against M. abscessus, whereas the ratio between ceftazidime and avibactam is redundant, due to inactivity of ceftazidime to inhibit the bacteria. We have identified that the use of imipenem and meropenem alongside either relebactam or avibactam yield low minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for each M. abscessus subspecies, which are within the therapeutically achievable concentration ranges within the epithelial lining fluid of the lungs. We propose the implementation of imipenem with relebactam in place of stand-alone imipenem into the current treatment regime, alongside meropenem, as a future front-line treatment option for M. abscessus complex infections.

8.
Sci Rep ; 10(1): 4540, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32139840

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

9.
Sci Rep ; 10(1): 928, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988293

RESUMO

Infections caused by Mycobacterium abscessus are increasing in prevalence in cystic fibrosis patients. This opportunistic pathogen's intrinsic resistance to most antibiotics has perpetuated an urgent demand for new, more effective therapeutic interventions. Here we report a prospective advance in the treatment of M. abscessus infection; increasing the susceptibility of the organism to amoxicillin, by repurposing the ß-lactamase inhibitor, relebactam, in combination with the front line M. abscessus drug imipenem. We establish by multiple in vitro methods that this combination works synergistically to inhibit M. abscessus. We also show the direct competitive inhibition of the M. abscessus ß-lactamase, BlaMab, using a novel assay, which is validated kinetically using the nitrocefin reporter assay and in silico binding studies. Furthermore, we reverse the susceptibility by overexpressing BlaMab in M. abscessus, demonstrating relebactam-BlaMab target engagement. Finally, we highlight the in vitro efficacy of this combination against a panel of M. abscessus clinical isolates, revealing the therapeutic potential of the amoxicillin-imipenem-relebactam combination.


Assuntos
Amoxicilina/farmacologia , Compostos Azabicíclicos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Imipenem/farmacologia , Mycobacterium abscessus/efeitos dos fármacos , Inibidores de beta-Lactamases/farmacologia , Amoxicilina/uso terapêutico , Compostos Azabicíclicos/metabolismo , Compostos Azabicíclicos/uso terapêutico , Sítios de Ligação , Cefalosporinas/metabolismo , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Imipenem/uso terapêutico , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mycobacterium abscessus/enzimologia , Plasmídeos/genética , Inibidores de beta-Lactamases/metabolismo , beta-Lactamases/genética , beta-Lactamases/metabolismo
10.
Microorganisms ; 7(3)2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30909391

RESUMO

Mycobacteria are a large family of over 100 species, most of which do not cause diseases in humans. The majority of the mycobacterial species are referred to as nontuberculous mycobacteria (NTM), meaning they are not the causative agent of tuberculous (TB) or leprosy, i.e., Mycobacterium tuberculous complex and Mycobacterium leprae, respectively. The latter group is undoubtedly the most infamous, with TB infecting an estimated 10 million people and causing over 1.2 million deaths in 2017 alone TB and leprosy also differ from NTM in that they are only transmitted from person to person and have no environmental reservoir, whereas NTM infections are commonly acquired from the environment. It took until the 1950's for NTM to be recognised as a potential lung pathogen in people with underlying pulmonary disease and another three decades for NTM to be widely regarded by the medical community when Mycobacterium avium complex was identified as the most common group of opportunistic pathogens in AIDS patients. This review focuses on an emerging NTM called Mycobacterium abscessus (M. abs). M. abs is a rapidly growing NTM that is responsible for opportunistic pulmonary infections in patients with structural lung disorders such as cystic fibrosis and bronchiectasis, as well as a wide range of skin and soft tissue infections in humans. In this review, we discuss how we came to understand the pathogen, how it is currently treated and examine drug resistance mechanisms and novel treatments currently in development. We highlight the urgent need for new and effective treatments for M. abs infection as well as improved in vivo methods of efficacy testing.

11.
Science ; 354(6313): 751-757, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27846606

RESUMO

Lung infections with Mycobacterium abscessus, a species of multidrug-resistant nontuberculous mycobacteria, are emerging as an important global threat to individuals with cystic fibrosis (CF), in whom M. abscessus accelerates inflammatory lung damage, leading to increased morbidity and mortality. Previously, M. abscessus was thought to be independently acquired by susceptible individuals from the environment. However, using whole-genome analysis of a global collection of clinical isolates, we show that the majority of M. abscessus infections are acquired through transmission, potentially via fomites and aerosols, of recently emerged dominant circulating clones that have spread globally. We demonstrate that these clones are associated with worse clinical outcomes, show increased virulence in cell-based and mouse infection models, and thus represent an urgent international infection challenge.


Assuntos
Doenças Transmissíveis Emergentes/microbiologia , Fibrose Cística/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/classificação , Animais , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/patologia , Doenças Transmissíveis Emergentes/transmissão , Fibrose Cística/epidemiologia , Fibrose Cística/patologia , Genoma Bacteriano , Genômica , Humanos , Incidência , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos SCID , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/patologia , Infecções por Mycobacterium não Tuberculosas/transmissão , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Filogenia , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/patologia , Pneumonia Bacteriana/transmissão , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
12.
Arch Dis Child ; 101(9): e2, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27540192

RESUMO

AIM: With pressures on junior doctors' availability in the NHS, non-medical prescribing is topical. Independent Nurse Prescribers (INPs) can prescribe any licensed medicine for any medical condition within their level of competence.1 An audit was undertaken of the four INPs employed by the Respiratory Department evaluating current prescribing practices. METHOD: The requirement for this audit was identified by the multidisciplinary team (MDT) and Trust approval was obtained. A data collection form was designed capturing patient demographics and full details of prescribed items.Over a 3 month period (August to October 2014) outpatient cystic fibrosis (CF) and respiratory prescriptions were studied using cluster sampling. Over a 6 week period prescription requests by CF INPs faxed to General Practitioners (GPs) were reviewed. INPs also prescribe via telephone, documenting advice on trust forms; these were preliminarily audited. All data was analysed using Microsoft Excel. Legality of prescriptions and adherence to national and local guidelines were evaluated. Reference keys were used to designate non-adherence post-application of exclusion criteria. RESULTS: A total of 77 outpatient prescriptions (45 CF and 32 respiratory) were completed by the 4 INPs, containing 122 items (72 CF and 50 respiratory). Of the CF prescribed items 21 were oral antibiotics (29%). Respiratory INPs mainly prescribed 14 inhaler devices (28%) and 12 inhaled bronchodilators (24%).All INP prescriptions met legal requirements. Basic details of medicinal products (drug name and dose) were documented for all items. A key finding was that duration/quantity was not indicated for 27 (54%) respiratory items.After applying exclusion criteria, of the CF prescribed items, 56/59 (95%) adhered to national guidelines and 47/66 (71%) followed local guidelines. The leading reason for not following local guidelines was not documenting allergy status. Of the respiratory prescribed items, 34 (100%) adhered to national guidelines and 31/32 (97%) followed local guidelines.A total of 33 faxes (with 38 items) were completed and 35 items (92%) were oral antibiotics. Drug name, dose and frequency were stated for all items. From the faxed items, 38 (100%) adhered to national guidelines and 32/33 (97%) followed local guidelines.Over 5 days, CF INPs provided telephone advice for 12 patients. Of these, 6 patients had respiratory exacerbation. Telephone advice led to faxes being sent to GPs for 9 patients. This was preliminary data with a re-audit planned after amendment of trust form. CONCLUSION: Overall INP prescribing was found to be safe and effective. This review enabled education of the respiratory team of prescribing practices via a local audit meeting. The positive contribution that INPs provide to patient care was highlighted as they improve the patient journey and support the MDT. The demand for INP prescribing in particular with CF has provided opportunity for a pharmacist prescriber to join the CF MDT. It is recommended medical and pharmacist prescribing to be reviewed.

13.
J Immunol ; 193(4): 1895-910, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25031461

RESUMO

The innate immune system has been implicated in several neurodegenerative diseases, including HIV-1-associated dementia. In this study, we show that genetic ablation of CCR5 prevents microglial activation and neuronal damage in a transgenic model of HIV-associated brain injury induced by a CXCR4-using viral envelope gp120. The CCR5 knockout (KO) also rescues spatial learning and memory in gp120-transgenic mice. However, the CCR5KO does not abrogate astrocytosis, indicating it can occur independently from neuronal injury and behavioral impairment. To characterize further the neuroprotective effect of CCR5 deficiency we performed a genome-wide gene expression analysis of brains from HIVgp120tg mice expressing or lacking CCR5 and nontransgenic controls. A comparison with a human brain microarray study reveals that brains of HIVgp120tg mice and HIV patients with neurocognitive impairment share numerous differentially regulated genes. Furthermore, brains of CCR5 wild-type and CCR5KO gp120tg mice express markers of an innate immune response. One of the most significantly upregulated factors is the acute phase protein lipocalin-2 (LCN2). Using cerebrocortical cell cultures, we find that LCN2 is neurotoxic in a CCR5-dependent fashion, whereas inhibition of CCR5 alone is not sufficient to abrogate neurotoxicity of a CXCR4-using gp120. However, the combination of pharmacologic CCR5 blockade and LCN2 protects neurons from toxicity of a CXCR4-using gp120, thus recapitulating the finding in CCR5-deficient gp120tg mouse brain. Our study provides evidence for an indirect pathologic role of CCR5 and a novel protective effect of LCN2 in combination with inhibition of CCR5 in HIV-associated brain injury.


Assuntos
Complexo AIDS Demência/genética , Proteínas de Fase Aguda/metabolismo , Proteína gp120 do Envelope de HIV/genética , HIV-1 , Lipocalinas/metabolismo , Proteínas Oncogênicas/metabolismo , Receptores CCR5/genética , Proteínas de Fase Aguda/biossíntese , Animais , Antagonistas dos Receptores CCR5 , Células Cultivadas , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Gliose , Lipocalina-2 , Lipocalinas/biossíntese , Aprendizagem em Labirinto , Memória , Camundongos , Camundongos Knockout , Microglia/patologia , Proteínas Oncogênicas/biossíntese , Receptores CCR5/biossíntese , Receptores CXCR4/metabolismo , Transdução de Sinais/genética
15.
J Neuroimmune Pharmacol ; 7(2): 306-18, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22124968

RESUMO

Infection with HIV-1 frequently affects the brain and causes NeuroAIDS prior to the development of overt AIDS. The HIV-1 envelope protein gp120 interacts with host CD4 and chemokine co-receptors to initiate infection of macrophages and lymphocytes. In addition, the virus or fragments of it, such as gp120, cause macrophages to produce neurotoxins and trigger neuronal injury and apoptosis. Moreover, the two major HIV co-receptors, the chemokine receptors CCR5 and CXCR4, serve numerous physiological functions and are widely expressed beyond immune cells, including cells in the brain. Therefore, HIV co-receptors are poised to play a direct and indirect part in the development of NeuroAIDS. Although rodents are not permissive to infection with wild type HIV-1, viral co-receptors - more than CD4 - are highly conserved between species, suggesting the animals can be suitable models for mechanistic studies addressing effects of receptor-ligand interaction other than infection. Of note, transgenic mice expressing HIV gp120 in the brain share several pathological hallmarks with NeuroAIDS brains. Against this background, we will discuss recently completed or initiated, ongoing studies that utilize HIV co-receptor knockout and viral gp120-transgenic mice as models for in vitro and in vivo experimentation in order to address the potential roles of HIV gp120 and its co-receptors in the development of NeuroAIDS.


Assuntos
Complexo AIDS Demência/metabolismo , Modelos Animais de Doenças , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1 , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Complexo AIDS Demência/imunologia , Animais , Técnicas de Inativação de Genes , Proteína gp120 do Envelope de HIV/imunologia , Camundongos , Receptores CCR5/imunologia , Receptores CXCR4/imunologia , Receptores de HIV/imunologia , Receptores de HIV/metabolismo
16.
Glia ; 59(4): 627-40, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21294162

RESUMO

White matter pathology has been documented in the brains of familial Alzheimer's disease (FAD)-afflicted individuals during presymptomatic and preclinical stages of AD. How these defects in myelination integrity arise and what roles they may play in AD pathophysiology have yet to be fully elucidated. We previously demonstrated that triple-transgenic AD (3xTg-AD) mice, which harbor the human amyloid precursor Swedish mutation, presenilin-1 M146V (PS1(M146V) ) knock-in mutation, and tau(P301L) mutation, exhibit myelin abnormalities analogous to FAD patients and that Aß(1-42) contributes to these white matter deficits. Herein, we demonstrate that the PS1(M146V) mutation predisposes mouse oligodendrocyte precursor (mOP) cells to Aß(1-42) -induced alterations in cell differentiation in vitro. Furthermore, PS1(M146V) expression compromised mOP cell function and MBP protein distribution, a process that is further aggravated with exposure to Aß(1-42) . We found that the myelination defect and MBP subcellular mislocalization triggered by PS1(M146V) and Aß(1-42) can be effectively prevented by treatment with the GSK-3ß inhibitor, TWS119, thereby implicating GSK-3ß kinase activity in this pathogenic cascade. Overall, this work provides further mechanistic insights into PS1(M146V) and Aß(1-42) -driven oligodendrocyte dysfunction andmyelin damage during early presymptomatic stages of AD, and provides a new target in oligodendrocytes for developing therapies designed to avert AD-related white matter pathology.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Diferenciação Celular/fisiologia , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Presenilina-1/genética , Peptídeos beta-Amiloides/farmacologia , Análise de Variância , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Citometria de Fluxo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Mutação , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/genética , Bainha de Mielina/patologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/patologia , Presenilina-1/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Immunol ; 185(8): 4883-95, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20855878

RESUMO

HIV-1 envelope protein gp120 has been implicated in neurotoxin production by monocytic cells (i.e., macrophages and microglia), as well as in the pathogenesis of HIV-1-associated neurocognitive disorders. We previously showed in cerebrocortical cell cultures from rodents containing microglia, astrocytes, and neurons that overall inhibition of p38 MAPK signaling abrogated the neurotoxic effect of HIV-1 gp120. However, the time course of p38 MAPK activation and the contribution of this kinase in the various cell types remained unknown. In this study, we found that active p38 MAPK is required in monocytic lineage cells (i.e., macrophages and microglia) and neuronal cells for HIV gp120-induced neurotoxicity to occur. In cerebrocortical cell cultures, HIV-1 gp120 stimulated a time-dependent overall increase in active p38 MAPK, and the activated kinase was primarily detected in microglia and neurons. Interestingly, increased activation of p38 MAPK and neuronal death in response to gp120 were prevented by prior depletion of microglia or the presence of CCR5 ligand CCL4 or p38 MAPK inhibitors. In human monocytic THP-1 cells and primary monocyte-derived macrophages, HIV gp120-stimulated production of neurotoxins was abrogated by prior introduction into the cells of a dominant-negative p38 MAPK mutant or p38 MAPK small interfering RNA. In addition, the neurotoxic effects of cell-free supernatants from gp120-stimulated monocytic THP-1 cells were prevented in microglia-depleted cerebrocortical cells pretreated with a pharmacological inhibitor of p38 MAPK. Thus, p38 MAPK signaling was critical, upon exposure to HIV gp120, for the neurotoxic phenotype of monocytic cells and subsequent toxin-initiated neuronal apoptosis.


Assuntos
Proteína gp120 do Envelope de HIV/metabolismo , Monócitos/metabolismo , Neurônios/metabolismo , Neurotoxinas/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Células Cultivadas , Ativação Enzimática/fisiologia , Imunofluorescência , Humanos , Immunoblotting , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
18.
Am J Pathol ; 177(3): 1422-35, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20696774

RESUMO

The detection of myelin disruptions in Alzheimer's disease (AD)-affected brain raises the possibility that oligodendrocytes undergo pathophysiological assault over the protracted course of this neurodegenerative disease. Oligodendrocyte compromise arising from direct toxic effects imparted by pathological amyloid-beta peptides and/or through signals derived from degenerating neurons could play an important role in the disease process. We previously demonstrated that 3xTg-AD mice, which harbor the human amyloid precursor protein Swedish mutant transgene, presenilin knock-in mutation, and tau P301L mutant transgene, exhibit significant alterations in overall myelination patterns and oligodendrocyte status at time points preceding the appearance of amyloid and tau pathology. Herein, we demonstrate that Abeta(1-42) leads to increased caspase-3 expression and apoptotic cell death of both nondifferentiated and differentiated mouse oligodendrocyte precursor (mOP) cells in vitro. Through use of a recombinant adeno-associated virus serotype-2 (rAAV2) vector expressing an Abeta(1-42)-specific intracellular antibody (intrabody), oligodendrocyte and myelin marker expression, as well as myelin integrity, were restored in the vector-infused brain regions of 3xTg-AD mice. Overall, this work provides further insights into the impact of Abeta(1-42)-mediated toxicity on the temporal and spatial progression of subtle myelin disruption during the early presymptomatic stages of AD and may help to validate new therapeutic options designed to avert these early impairments.


Assuntos
Córtex Entorrinal/patologia , Bainha de Mielina/patologia , Oligodendroglia/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Análise de Variância , Animais , Apoptose/genética , Western Blotting , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Córtex Entorrinal/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica , Bainha de Mielina/genética , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
19.
Glia ; 57(1): 54-65, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18661556

RESUMO

Alzheimer's disease (AD) is a progressively debilitating brain disorder pathologically defined by extracellular amyloid plaques, intraneuronal neurofibrillary tangles, and synaptic disintegrity. AD has not been widely considered a disease of white matter, but more recent evidence suggests the existence of abnormalities in myelination patterns and myelin attrition in AD-afflicted human brains. Herein, we demonstrate that triple-transgenic AD (3xTg-AD) mice, which harbor the human amyloid precursor protein Swedish mutant transgene, presenilin knock-in mutation, and tau P301L mutant transgene, exhibit significant region-specific alterations in myelination patterns and in oligodendrocyte marker expression profiles at time points preceding the appearance of amyloid and tau pathology. These immunohistochemical signatures are coincident with age-related alterations in axonal and myelin sheath ultrastructure as visualized by comparative electron microscopic examination of 3xTg-AD and nontransgenic mouse brain tissue. Overall, these findings indicate that 3xTg-AD mice represent a viable model in which to examine mechanisms underlying AD-related myelination and neural transmission defects that occur early during presymptomatic stages of the disease process.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Bainha de Mielina/patologia , Placa Amiloide/patologia , Tauopatias/patologia , Fatores Etários , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Bainha de Mielina/genética , Bainha de Mielina/ultraestrutura , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Placa Amiloide/genética , Placa Amiloide/ultraestrutura , Tauopatias/genética , Tauopatias/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Proteínas tau/ultraestrutura
20.
Pediatr Surg Int ; 22(12): 1009-14, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17039385

RESUMO

Ultrasonography (US) is considered to be adequate for the preoperative evaluation of childhood empyema. This study was aimed to improve awareness that paediatric intra-thoracic tumours can mimic childhood post-pneumonic empyema and highlights the value of computed tomogram (CT) scan with intravenous (IV) contrast in preoperative evaluation of childhood empyema. The data were analysed on eight children (four boys and four girls) presented at the median age of 6.2 years (1.8-15 years) for the management of empyema and later confirmed to have intra-thoracic tumours. Intra-thoracic tumours in 8 (5.3%) children out of 150 cases of post-pneumonic empyema were managed during the study period. All eight had clinical features, increased white cell count, raised inflammatory markers and biochemical parameters suggestive of childhood empyema. Chest X-ray showed localised opacity in 3/8 while in other five suggested significant pleural collection with mediastinal shift. Additional investigations in referring hospital were suggestive of empyema in four children; US in three, CT scan without IV contrast in one. Referring hospital carried out non-diagnostic thoracocentesis in four children with blood stained pleural tap in two. In four children corroborative evidence suggestive of infection within pleural cavity and acute respiratory distress led to an emergency mini-thoracotomy resulting in significant intra-operative bleeding in two children. Histology on biopsy of the infected material showed primitive neuroectodermal tumour (PNET) in one, pleuropulmonary blastoma in one, metastatic malignant melanoma in one and cytology of pleural fluid diagnosed lymphoma in one. Pre-operative CT scan with IV contrast in four children correctly identified underlying intra-thoracic tumour (two benign teratoma, two PNET). In two cases CT with IV contrast was performed because chest X-ray suggested mediastinal loculated empyema while in other two high clinical index of suspicion prompted preoperative evaluation with CT scan with IV contrast. We advocate caution and increased awareness before considering therapeutic options in childhood empyema and recommend preoperative CT scan with IV contrast in some selected and unusual cases.


Assuntos
Empiema Pleural/etiologia , Neoplasias Torácicas/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Empiema Pleural/diagnóstico por imagem , Feminino , Humanos , Lactente , Masculino , Punções , Estudos Retrospectivos , Teratoma/complicações , Teratoma/diagnóstico , Toracotomia , Tomografia Computadorizada por Raios X
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