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1.
Clin Exp Ophthalmol ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853535

RESUMO

BACKGROUND: This systematic review and meta-analysis quantitatively examines the efficacy of angle-based minimally invasive glaucoma surgery (MIGS) in normal tension glaucoma (NTG). METHODS: A literature search was performed on Medline, Embase, PubMed, CINAHL and Cochrane Library from inception until 20 December 2022. Pilot, cohort, observational studies and randomised controlled trials including at least 5 subjects undergoing angle-based MIGS (trabecular-bypass devices, excisional trabeculotomy, goniotomy and ab-interno canaloplasty) for NTG, with or without cataract surgery, were included. Meta-analysis of continuous outcome using the meta routine in R version 2022.12.0+353 was performed to determine mean intraocular pressure (IOP) and anti-glaucoma medication (AGM) reduction post-operatively. RESULTS: Of the 846 studies initially identified, 15 studies with a pooled total of 367 eyes which underwent combined phacoemulsification and angle-based MIGS were included for final meta-analysis. Outcomes of the iStent were reported in 5 studies, iStent inject in 7 studies, Hydrus Microstent in 1 study, Kahook Dual Blade in 3 studies, and Trabectome in 2 studies. There was significant reduction in both IOP and AGM post-operatively at 6 months (2.44 mmHg, 95%CI: 1.83-3.06; 1.21 AGM, 95%CI: 0.99-1.44), 12 months (2.28 mmHg, 95%CI: 1.71-2.84; 1.18 AGM, 95%CI: 0.90-1.47), 24 months (2.10 mmHg, 95%CI: 1.51-2.68; 1.26 AGM, 95%CI: 0.85-1.68) and 36 months (2.43 mmHg, 95%CI: 1.71-3.15, 0.87 AGM, 95%CI: 0.21-1.53) (all p < 0.05). Subgroup analysis on combined phacoemulsification-iStent inject surgery demonstrated a reduction in both IOP (2.31 mmHg, 95%CI: 1.07-3.56, p < 0.001) and AGM (1.07 AGM, 95%CI: 0.86-1.29, p < 0.001) at 12 months post-operatively. CONCLUSIONS: Angle-based MIGS combined with phacoemulsification effectively reduces IOP and AGM in NTG eyes for up to 36 months after surgery.

3.
Surv Ophthalmol ; 69(2): 253-264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37804869

RESUMO

Assessing anterior chamber inflammation is highly subjective and challenging. Although various grading systems attempt to offer objectivity and standardization, the clinical assessment has high interobserver variability. Traditional techniques, such as laser flare meter and fluorophotometry, are not widely used since they are time-consuming. With the development of optical coherence tomography with high sensitivity, direct imaging offers an excellent alternative to assess objectively inflammation with the potential for automated analysis. We describe various anterior chamber inflammation grading methods and discuss their utility, advantages, and disadvantages.


Assuntos
Uveíte Anterior , Humanos , Câmara Anterior/diagnóstico por imagem , Inflamação/diagnóstico , Tomografia de Coerência Óptica/métodos , Testes Visuais
5.
Surv Ophthalmol ; 68(2): 290-307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36191648

RESUMO

Immunoglobulin A nephropathy (IgAN) is a rare but important systemic disease with or without ocular manifestations. We describe 4 cases of IgAN presenting with scleritis and review the various ocular manifestations in patients with IgAN. We found 55 cases with ocular manifestations in patients with prior or newly-diagnosed IgAN described in 38 publications. The most common ocular manifestations of IgAN were episcleritis (23.6%), scleritis (16.4%), hypertensive retinopathy or retinal vasculopathy (20.0%), and uveitis (14.5%). The median age at presentation was 36.5 years, with 54.5% female patients. 61.8% had history of IgAN prior to ocular involvement, while 29.1% had ocular presentations as the first manifestation of IgAN. The majority received systemic corticosteroids and/or immunosuppressants. Additionally, we report 4 women with anterior scleritis and previous diagnosis of IgAN. All 4 were treated with topical and systemic corticosteroids. Three out of 4 patients had no recurrence for at least 1 year since the first presentation. IgAN is a rare but important systemic association to be considered in ocular inflammatory conditions. Timely recognition and comanagement of the disease with nephrologist could reduce disease morbidity.


Assuntos
Glomerulonefrite por IGA , Esclerite , Uveíte , Humanos , Feminino , Adulto , Masculino , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/diagnóstico , Esclerite/diagnóstico , Esclerite/etiologia , Olho , Corticosteroides
6.
BMJ Glob Health ; 7(10)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36220307

RESUMO

INTRODUCTION: With limited resources, attaining maximal average health service coverage can be at odds with maximising equity which attempts to promote greater reach among underserved populations. In this study, we examined the trade-offs in immunisation coverage levels and equity for children under 5 years of age in Pakistan across various subpopulations who can be targeted with different combinations of immunisation service modalities. METHODS: We conducted a detailed costing exercise across 16 geographically and demographically diverse districts in Pakistan. These data were the basis for (a) technical efficiency benchmarking via Data Envelopment Analysis to identify potential efficiency gains by location, delivery model and cost ingredient; (b) allocative efficiency optimisation modelling to understand how resource allocations could be optimised and to devise recommended budget allocations and operational metrics. Finally, the hypothetical overall efficiency gains attainable were estimated if available resources were allocated with the optimal emphases, and if service delivery models operated at productivity levels at the benchmarked frontier of efficiency. RESULTS: Benchmarking suggests that ~44% of delivery models are running efficiently and 37% are highly inefficient. While coverage and equity are usually at odds, surprisingly, the optimisation modelling revealed that substantial improvements in equity between subpopulations does not necessarily cost very much in overall immunisation coverage: theoretically, equity can be achieved while still attaining close to maximal immunisation coverage. Overall, analyses suggest greater emphases should be placed on outreach delivery models which particularly target rural areas and slum populations. CONCLUSION: The unit cost differentials within districts are not sufficiently large for there to be a large reduction in potential Fully Immunised Children coverage if one focuses on maximising equity. However, reallocations of programme budgets can have a significant impact on equity outcomes, particularly at current low spending amounts. Therefore, it is recommended to address equity as the key objective in national immunisation programming.


Assuntos
Imunização , Cobertura Vacinal , Criança , Pré-Escolar , Custos e Análise de Custo , Humanos , Paquistão , Vacinação
7.
Health Res Policy Syst ; 19(1): 153, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34963496

RESUMO

BACKGROUND: Globally, policy-makers face challenges to using evidence in health decision-making, particularly lack of interaction between research and policy. Knowledge-brokering mechanisms can fill research-policy gaps and facilitate evidence-informed policy-making. In Myanmar, the need to promote evidence-informed policy is significant, and thus a mechanism was set up for this purpose. This paper discusses lessons learned from the development of the Knowledge Broker Group-Myanmar (KBG-M), supported by the Johns Hopkins Bloomberg School of Public Health's Applied Mental Health Research Group (JHU) and Community Partners International (CPI). METHODS: Sixteen stakeholders were interviewed to explore challenges in formulating evidence-informed policy. Two workshops were held: the first to further understand the needs of policy-makers and discuss knowledge-brokering approaches, and the second to co-create the KBG-M structure and process. The KBG-M was then envisioned as an independent body, with former officials of the Ministry of Health and Sports (MoHS) and representatives from the nongovernmental sector actively engaging in the health sector, with an official collaboration with the MoHS. RESULTS: A development task force that served as an advisory committee was established. Then, steps were taken to establish the KBG-M and obtain official recognition from the MoHS. Finally, when the technical agreement with the MoHS was nearly complete, the process stopped because of the military coup on 1 February 2021, and is now on hold indefinitely. CONCLUSIONS: Learning from this process may be helpful for future or current knowledge-brokering efforts, particularly in fragile, conflict-affected settings. Experienced and committed advisory committee members enhanced stakeholder relationships. Responsive coordination mechanisms allowed for adjustments to a changing bureaucratic landscape. Coordination with similar initiatives avoided overlap and identified areas needing technical support. Recommendations to continue the work of the KBG-M itself or similar platforms include the following: increase resilience to contextual changes by ensuring diverse partnerships, maintain advisory committee members experienced and influential in the policy-making process, ensure strong organizational and funding support for effective functioning and sustainability, have budget and timeline flexibility to allow sufficient time and resources for establishment, organize ongoing needs assessments to identify areas needing technical support and to develop responsive corrective approaches, and conduct information sharing and collaboration between stakeholders to ensure alignment.


Assuntos
Política de Saúde , Formulação de Políticas , Pessoal Administrativo , Humanos , Mianmar , Saúde Pública
8.
Case Rep Ophthalmol ; 12(1): 214-218, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33976685

RESUMO

PURPOSE: To report a case of recalcitrant pseudomonas keratitis with a rare presentation of hyphaema. OBSERVATION: A 45-year-old female was noted to have contact lens-related pseudomonas keratitis with hyphaema. The organism was refractory to multiple antibiotics and only responded to Tazocin eye drops. CONCLUSION AND IMPORTANCE: Hyphaema is a rare presentation in bacterial keratitis and could represent infection with an especially virulent organism. Use of Aspirin could precipitate hyphaema in infective keratitis. Alternative antibiotic choices such as Tazocin, colistin, meropenem, and imipenem can be considered when standard therapy is ineffective for multidrug-resistant Pseudomonas keratitis.

9.
BMJ Sex Reprod Health ; 47(3): 179-184, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33122257

RESUMO

BACKGROUND: Maternal mortality in Myanmar is one of the highest in the WHO South-East Asian region. Additionally, the country has a high unmet need for contraception and low rates of uptake of long-acting reversible contraceptive methods (LARCs) including intrauterine devices (IUDs) and implants. Engagement with health professionals around the time of a birth is an ideal opportunity for women to access contraception but immediate postpartum provision is not widely offered in Myanmar. METHODS: We undertook a cross-sectional survey of women immediately postpartum at two hospitals in Yangon to investigate their knowledge, and past use of, contraceptive methods and their plans for postpartum contraception including perceptions of implants and IUDs. Four trained obstetrics staff collected data using electronic tablets between January 2017 and January 2018. RESULTS: Of the 1755 participants, 55.1% had used pills and 42.2% injectables. In contrast, only 0.5% had used an IUD and 0.3% an implant. Few women (4.4%) anticipated starting contraception immediately postpartum and only a minority would consider future use of an implant (36.9%) or an IUD (13.0%). Fear of side effects was the major barrier to future implant and IUD uptake, reported by 64.5% and 62.5%, respectively. CONCLUSIONS: Women in maternity care in Yangon have some awareness of IUDs and implants but many hold misconceptions about their side effects leading to reluctance to use. Reducing the unmet need for contraception and improving maternal outcomes in Myanmar could be achieved by improving education, policy and practice around immediate postpartum contraception provision, with a particular focus on LARC methods.


Assuntos
Serviços de Saúde Materna , Anticoncepção , Estudos Transversais , Feminino , Humanos , Mianmar , Período Pós-Parto , Gravidez
10.
PLoS One ; 15(8): e0237787, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822375

RESUMO

INTRODUCTION: Afghanistan is affected by one of the world's longest protracted armed conflicts, frequent natural disasters, disease outbreaks and large population movements and it suffers from a high burden of tuberculosis (TB), including rifampicin-resistant TB (RR-TB). The study shows Médecins Sans Frontières' experiences with care for patients with RR-TB in Kandahar Province. We describe the uptake of RR-TB treatment, how World Health Organisation criteria for the choice between the short and an individualized regimen were implemented, and treatment outcomes. METHODS: This is a retrospective cohort analysis of routinely collected data from RR-TB patients enrolled in care from 2016 until 2019. Descriptive analysis was performed to present characteristics of patients and treatment outcomes. Multivariable Cox analysis was performed to identify risk factors for having an unfavourable treatment outcome. RESULTS: Out of 146 enrolled RR-TB patients, 112 (76.7%) started treatment: 41 (36.6%) and 71 (63.4%) with the short and individualized treatment regimen, respectively. Of 82 with results for fluoroquinolone susceptibility, 39 (47.6%) had fluoroquinolone-resistant TB. Seven patients with initially fluoroquinolone-resistant TB and three pregnant women started the short regimen and 18 patients eligible for the short regimen started the injectable-free individualized regimen. Overall, six-month smear and culture conversion were 98.7% and 97.1%, respectively; treatment success was 70.1%. Known initial fluoroquinolone resistance (aHR 3.77, 95%CI:1.53-9.27) but not choice of regimen predicted having an unfavourable outcome. CONCLUSION: Even though criteria for the choice of treatment regimen were not applied strictly, we have achieved acceptable outcomes in this cohort. To expand RR-TB care, treatment regimens should fit provision at primary health care level and take patient preferences into account.


Assuntos
Antituberculosos/uso terapêutico , Fluoroquinolonas/uso terapêutico , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adolescente , Adulto , Afeganistão/epidemiologia , Feminino , Humanos , Masculino , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Organização Mundial da Saúde , Adulto Jovem
12.
Nat Geosci ; 12(10): 863-868, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31579400

RESUMO

Convergence between the Indian and Asian plates has reshaped large parts of Asia, changing regional climate and biodiversity. Yet geodynamic models fundamentally diverge on how convergence was accommodated since the India-Asia collision. Here we report paleomagnetic data from the Burma Terrane, at the eastern edge of the collision zone and famous for its Cretaceous amber biota, to better determine the evolution of the India-Asia collision. The Burma Terrane was part of a Trans-Tethyan island arc and stood at a near-equatorial southern latitude at ~95 Ma, suggesting island endemism for the Burmese amber biota. The Burma Terrane underwent significant clockwise rotation between ~80-50 Ma, causing its subduction margin to become hyper-oblique. Subsequently, it was translated northward on the Indian Plate, by an exceptional distance of at least 2000 km, along a dextral strike-slip fault system in the east. Our reconstructions are only compatible with geodynamic models involving a first collision of India with a near-equatorial Trans-Tethyan subduction system at ~60 Ma, followed by a later collision with the Asian margin.

13.
Free Radic Biol Med ; 120: 303-310, 2018 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-29551638

RESUMO

Proteases and reactive oxygen species (ROS) have long been implicated in playing key roles in host tissue injury at sites of inflammation dominated by macrophage activations and/or neutrophil infiltrations. Imbalances between proteases/antiproteases and ROS/antioxidants are recognized to contribute to amplification of inflammatory-based host tissue injury. This has been especially well-documented in such respiratory tract diseases as chronic obstructive pulmonary disease, cystic fibrosis, and acute respiratory distress syndrome. Inflammation-related protease/ROS disequilibria are further confounded by recognition that proteases can increase ROS by several different mechanisms and that ROS can inactivate proteases. The major human antiprotease, alpha-1 antitrypsin (AAT), is dramatically inactivated by ROS. AAT deficiency is the most prevalent genetic predisposing factor leading to emphysema, a condition treated by replacement infusions of plasma-derived AAT (hAAT) at a cost of up to $200,000 per year per patient. An updated method for production of a plant-made recombinant AAT (prAAT) engineered for enhanced oxidation resistance compared to hAAT is presented. Plant-made recombinant AAT shows comparable antiprotease activity to hAAT, and retains full activity under oxidative conditions that would deactivate hAAT. Additionally, we show that prAAT has similar effectiveness in preventing neutrophil elastase-induced cell death in an in vitro human bronchial epithelial cell culture model. We conclude that prAAT is potentially a "biobetter" AAT product that could be made available to individuals with a wide spectrum of inflammatory disorders characterized by overly aggressive neutrophilic infiltrations.


Assuntos
Nicotiana , Engenharia de Proteínas/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , alfa 1-Antitripsina , Humanos , Oxirredução , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo
14.
Ocul Immunol Inflamm ; 26(5): 654-659, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28318359

RESUMO

Zika virus (ZIKV), a mosquito-borne flavivirus, is the latest global health concern. Transmission is mainly via Aedes mosquitoes and the infection can be diagnosed on molecular or serologic testings. It typically causes a mild self-remitting illness of low-grade fever, maculopapular rash, and myalgia, but when severe, it is associated with neurological deficits and congenital structural defects. Ocular manifestations are usually mild like nonpurulent conjunctivitis in adults, though it may be linked to uveitis, maculopathy, and hypertensive iridocyclitis. Ocular signs seem to be more significant in congenital ZIKV-macular pigment mottling, neuroretinal atrophy with macular involvement, iris coloboma, and changes in retinal vasculature are noted in infants with infected mothers. Risk factors include ZIKV infection in first trimester and smaller cephalic diameter at birth. Hence, ophthalmic examination in newborns is now recommended. Currently, prevention and active surveillance are integral as there is no known vaccine, and treatment is only symptomatic.


Assuntos
Surtos de Doenças , Infecções Oculares Virais/epidemiologia , Infecção por Zika virus/epidemiologia , Zika virus/genética , Infecções Oculares Virais/virologia , Saúde Global , Humanos , Fatores de Risco , Infecção por Zika virus/virologia
16.
Retina ; 37(11): e144-e145, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28984740
17.
Nepal J Ophthalmol ; 9(18): 108-111, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-29634698

RESUMO

Visual impairment is a crippling condition affecting quality of life and depriving patients of many opportunities. It is associated with increased mortality rates directly through occurrence of adverse events such as falls and impaired emotional well-being, and indirectly through visual impairment brought upon by systemic conditions such as diabetes and hypertension (Foong et al. 2008, Fong et al. 2014, Khanna et al. 2013, Song et al.2014, Wang et al. 1999). The number of patients suffering from reversible causes of blindness is substantial. In 2010, World Health Organisation estimates that 285 million (4.25%) of the world's population is visually impaired, of which 39 million (14%) are blind. Approximately, 80% of the visual impairment is preventable. Notable causes of preventable blindness include cataracts (51%), glaucoma (8%), age-related macular degeneration (5%), corneal opacities (4%), trachoma (3%) and uncorrected refractive errors (3%) (WHO, 2015). These conditions can be easily diagnosed and treated by ophthalmologists if adequate resources are available. It is increasingly challenging for the ophthalmologists and current healthcare systems to meet the ever-expanding demands of patients with reversible causes of blindness.


Assuntos
Cegueira/prevenção & controle , Saúde Pública/métodos , Qualidade de Vida , Baixa Visão/prevenção & controle , Acuidade Visual , Pessoas com Deficiência Visual/estatística & dados numéricos , Idoso , Cegueira/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Singapura/epidemiologia , Baixa Visão/epidemiologia
18.
J Lipid Res ; 57(6): 955-68, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27087439

RESUMO

Dysfunction of the cerebrovasculature plays an important role in vascular cognitive impairment (VCI). Lipotoxic injury of the systemic endothelium in response to hydrolyzed triglyceride-rich lipoproteins (TGRLs; TGRL lipolysis products) or a high-fat Western diet (WD) suggests similar mechanisms may be present in brain microvascular endothelium. We investigated the hypothesis that TGRL lipolysis products cause lipotoxic injury to brain microvascular endothelium by generating increased mitochondrial superoxide radical generation, upregulation of activating transcription factor 3 (ATF3)-dependent inflammatory pathways, and activation of cellular oxidative stress and apoptotic pathways. Human brain microvascular endothelial cells were treated with human TGRL lipolysis products that induced intracellular lipid droplet formation, mitochondrial superoxide generation, ATF3-dependent transcription of proinflammatory, stress response, and oxidative stress genes, as well as activation of proapoptotic cascades. Male apoE knockout mice were fed a high-fat/high-cholesterol WD for 2 months, and brain microvessels were isolated by laser capture microdissection. ATF3 gene transcription was elevated 8-fold in the hippocampus and cerebellar brain region of the WD-fed animals compared with chow-fed control animals. The microvascular injury phenotypes observed in vitro and in vivo were similar. ATF3 plays an important role in mediating brain microvascular responses to acute and chronic lipotoxic injury and may be an important preventative and therapeutic target for endothelial dysfunction in VCI.


Assuntos
Fator 3 Ativador da Transcrição/genética , Traumatismo Cerebrovascular/genética , Disfunção Cognitiva/genética , Inflamação/genética , Lipoproteínas/metabolismo , Triglicerídeos/metabolismo , Fator 3 Ativador da Transcrição/biossíntese , Animais , Cerebelo/irrigação sanguínea , Cerebelo/metabolismo , Cerebelo/patologia , Traumatismo Cerebrovascular/metabolismo , Traumatismo Cerebrovascular/fisiopatologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental/efeitos adversos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Hipocampo/irrigação sanguínea , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Inflamação/metabolismo , Inflamação/fisiopatologia , Camundongos , Estresse Oxidativo/genética , Transdução de Sinais/genética
19.
Magn Reson Med ; 76(4): 1246-51, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26485349

RESUMO

PURPOSE: Previous studies indicated hyperlipidemia may be a risk factor for Alzheimer's disease, but the contributions of postprandial triglyceride-rich lipoprotein (TGRL) are not known. In this study, changes in blood-brain barrier diffusional transport following exposure to human TGRL lipolysis products were studied using MRI in a rat model. METHODS: Male Sprague-Dawley rats (∼180-250 g) received an i.v. injection of lipoprotein lipase (LpL)-hydrolyzed TGRL (n = 8, plasma concentration ≈ 150 mg human TGRL/dL). Controls received i.v. injection of either saline (n = 6) or LpL only (n = 6). The (1) H longitudinal relaxation rate R1 = 1/T1 was measured over 18 min using a rapid-acquired refocus-echo (RARE) sequence after each of three injections of the contrast agent Gd-DTPA. Patlak plots were generated for each pixel yielding blood-to-brain transfer coefficients, Ki , chosen for best fit to impermeable, uni-directional influx or bi-directional flux models using the F-test. RESULTS: Analysis from a 2-mm slice, 2-mm rostral to the bregma showed a 275% increase of mean Ki during the first 20 min after infusion of human TGRL lipolysis product that differed significantly compared with saline and LpL controls. This difference disappeared by 40 min mark. CONCLUSION: These results suggest human TGRL lipolysis products can lead to a transient increase in rat BBB permeability. Magn Reson Med 76:1246-1251, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Lipoproteínas/administração & dosagem , Angiografia por Ressonância Magnética/métodos , Triglicerídeos/administração & dosagem , Animais , Barreira Hematoencefálica/diagnóstico por imagem , Injeções Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley
20.
Inhal Toxicol ; 24(8): 506-17, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22746400

RESUMO

Increasing evidence suggests a role for a systemic pro-coagulant state in the pathogenesis of cardiac dysfunction subsequent to inhalation of airborne particulate matter (PM). We evaluated platelet activation, systemic cytokines and pulmonary gene expression in mice exposed to concentrated ambient particulate matter (CAPs) in the summer of 2008 (S08) and winter of 2009 (W09) from the San Joaquin Valley of California, a region with severe PM pollution episodes. Additionally, we characterized the PM from both exposures including organic compounds, metals, and polycyclic aromatic hydrocarbons. Mice were exposed to an average of 39.01 µg/m(3) of CAPs in the winter and 21.7 µg/m3 CAPs in the summer, in a size range less than 2.5 µm for 6 h/day for 5 days per week for 2 weeks. Platelets were analyzed by flow cytometry for relative size, shape, CD41, P-selectin and lysosomal associated membrane protein-1 (LAMP-1) expression. Platelets from W09 CAPs-exposed animals had a greater response to thrombin stimulation than platelets from S08 CAPs-exposed animals. Serum cytokines were analyzed by bead based immunologic assays. W09 CAPs-exposed mice had elevations in IL-2, MIP-1α, and TNFα. Laser capture microdissection (LCM) of pulmonary vasculature, parenchyma and airways all showed increases in CYP1a1 gene expression. Pulmonary vasculature showed increased expression of ICAM-1 and Nox-2. Our findings demonstrate that W09 CAPs exposure generated a greater systemic pro-inflammatory and pro-coagulant response to inhalation of environmentally derived fine and ultrafine PM. Changes in platelet responsiveness to agonists, seen in both exposures, strongly suggests a role for platelet activation in the cardiovascular and respiratory effects of particulate air pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Citocinas/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Material Particulado/toxicidade , Ativação Plaquetária/efeitos dos fármacos , Estações do Ano , Animais , California , Monitoramento Ambiental , Perfilação da Expressão Gênica , Exposição por Inalação , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula
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