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1.
Q J R Meteorol Soc ; 145(Suppl 1): 176-209, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31787783

RESUMO

Since the first International Cooperative for Aerosol Prediction (ICAP) multi-model ensemble (MME) study, the number of ICAP global operational aerosol models has increased from five to nine. An update of the current ICAP status is provided, along with an evaluation of the performance of ICAP-MME over 2012-2017, with a focus on June 2016-May 2017. Evaluated with ground-based Aerosol Robotic Network (AERONET) aerosol optical depth (AOD) and data assimilation quality MODerate-resolution Imaging Spectroradiometer (MODIS) retrieval products, the ICAP-MME AOD consensus remains the overall top-scoring and most consistent performer among all models in terms of root-mean-square error (RMSE), bias and correlation for total, fine- and coarse-mode AODs as well as dust AOD; this is similar to the first ICAP-MME study. Further, over the years, the performance of ICAP-MME is relatively stable and reliable compared to more variability in the individual models. The extent to which the AOD forecast error of ICAP-MME can be predicted is also examined. Leading predictors are found to be the consensus mean and spread. Regression models of absolute forecast errors were built for AOD forecasts of different lengths for potential applications. ICAP-MME performance in terms of modal AOD RMSEs of the 21 regionally representative sites over 2012-2017 suggests a general tendency for model improvements in fine-mode AOD, especially over Asia. No significant improvement in coarse-mode AOD is found overall for this time period.

2.
Elife ; 82019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30741632

RESUMO

In an effort to identify human endothelial cell (EC)-enriched lncRNAs,~500 lncRNAs were shown to be highly restricted in primary human ECs. Among them, lncEGFL7OS, located in the opposite strand of the EGFL7/miR-126 gene, is regulated by ETS factors through a bidirectional promoter in ECs. It is enriched in highly vascularized human tissues, and upregulated in the hearts of dilated cardiomyopathy patients. LncEGFL7OS silencing impairs angiogenesis as shown by EC/fibroblast co-culture, in vitro/in vivo and ex vivo human choroid sprouting angiogenesis assays, while lncEGFL7OS overexpression has the opposite function. Mechanistically, lncEGFL7OS is required for MAPK and AKT pathway activation by regulating EGFL7/miR-126 expression. MAX protein was identified as a lncEGFL7OS-interacting protein that functions to regulate histone acetylation in the EGFL7/miR-126 promoter/enhancer. CRISPR-mediated targeting of EGLF7/miR-126/lncEGFL7OS locus inhibits angiogenesis, inciting therapeutic potential of targeting this locus. Our study establishes lncEGFL7OS as a human/primate-specific EC-restricted lncRNA critical for human angiogenesis.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas de Ligação ao Cálcio/genética , Família de Proteínas EGF/genética , Loci Gênicos , MicroRNAs/genética , RNA Longo não Codificante/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Cardiomiopatia Dilatada/genética , Movimento Celular/genética , Proliferação de Células/genética , Família de Proteínas EGF/metabolismo , Feminino , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos BALB C , MicroRNAs/metabolismo , Modelos Biológicos , Neovascularização Fisiológica/genética , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética
3.
Exp Eye Res ; 170: 169-176, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29501382

RESUMO

MicroRNA miR-126 has been shown to be required for proper angiogenesis in several models. However, its expression, regulation and function in the mouse choroid remain unclear. Our previous data has shown that miR-126 expression is enriched in the endothelial cells (ECs) of the mouse choroid. Here we report that a 5.5 kb Egfl7/miR-126 promoter drives the expression of miR-126 in the choroid ECs during choroidal vascular development. The expression of miR-126 in the ECs is regulated by flow stress likely through Krüppel-like transcriptional factors. miR-126-/- mice show mildly delayed choroidal vascular development, but adult knockout mice develop periphery choroidal vascular lesions. This study suggests that miR-126 is largely dispensable for mouse choroidal development but required for maintaining choroidal vasculature integrity.


Assuntos
Corioide/irrigação sanguínea , Corioide/embriologia , Células Endoteliais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , MicroRNAs/genética , Neovascularização Fisiológica/genética , Animais , Proteínas de Ligação ao Cálcio , Células Cultivadas , Família de Proteínas EGF , Angiofluoresceinografia , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmídeos , Proteínas/genética , Reação em Cadeia da Polimerase em Tempo Real
4.
Curr Eye Res ; 42(4): 640-647, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27442082

RESUMO

PURPOSE: The cell surface LDL (low-density lipoprotein) receptor-related protein-1 (LRP-1) is important for lipid transport and several cell signaling processes. Human apolipoprotein E (apoE) is a ligand of LRP-1. We previously reported that a short peptide (apoEdp) mimicking the LRP-1 binding region of apoE prevents hyperglycemia-induced retinal endothelial cell dysfunction in vitro. The in-vivo outcome of apoE-based peptidomimetic inhibition of LRP-1 in the treatment of diabetic retinopathy is unknown. METHODS: Six months after streptozotocin induction of diabetes, male C57Bl/6 mice were intravitreally inoculated with apoEdp in a controlled release formulation. On the 15th day post-apoEdp treatment, mouse retinas were harvested to examine (1) blood-retinal-barrier (BRB) permeability by Evans blue dye, inflammatory leukostasis by concanavalin staining of leukocytes and LRP-1 pathway-related protein expression by Western blot analysis and gelatin zymography. RESULTS: Intravitreal apoEdp treatment of diabetic mice significantly reduced Evans blue extravasation and the number of adherent leukocytes in the diabetic mouse retinas. ApoEdp treatment inhibited the expression of extracellular matrix (ECM) degrading proteases heparanase and MMP-2, and restores the BRB tight junction proteins occludin and ZO-1. ApoEdp treatment also inhibited Wnt/ß-catenin-related expression of pro-inflammatory molecules ICAM-1, HIF-1α, and VEGF through negative regulation by LRP-1. CONCLUSION: Intravitreal apoEdp treatment of diabetic mice resulted a significant decrease in retinal vascular abnormalities through downregulation of LRP-1-related ECM protein degradation and Wnt/ß-catenin-related pro-angiogenic molecules.


Assuntos
Inibidores da Angiogênese/farmacologia , Apolipoproteínas E/farmacologia , Retinopatia Diabética/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Receptores de LDL/antagonistas & inibidores , Neovascularização Retiniana/prevenção & controle , Proteínas Supressoras de Tumor/antagonistas & inibidores , Animais , Glicemia/metabolismo , Barreira Hematorretiniana/fisiologia , Western Blotting , Permeabilidade Capilar , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/fisiopatologia , Proteínas da Matriz Extracelular/metabolismo , Injeções Intravítreas , Leucostasia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/fisiopatologia , Vasos Retinianos/fisiologia , Via de Sinalização Wnt/efeitos dos fármacos
5.
J Pharmacol Sci ; 131(2): 126-30, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27262904

RESUMO

PURPOSE: To determine the therapeutic efficacy of a novel rare sugar, l-psicose, for the treatment of HSV-1 induced herpetic stromal keratitis (HSK) in a mouse eye model. METHODS: One rare sugar l-psicose was assayed for HSV-1 inhibition of in vitro virus adsorption. The IC50 and IC90 values of l-psicose were determined using plaque reduction assay (PRA) in CV-1 cell. Female Balb/c mice were corneally infected with HSV-1, strain KOS-GFP; A topical eye drop treatment of l-psicose was started 24 h after infection and continued four times daily for ten consecutive days. The severity of HSK was monitored by slit lamp examination in a masked fashion and Infectious HSV-1 shedding was determined by PRA. RESULTS: l-psicose was found to have anti-viral activity in vitro at an IC50 dose of 99.5 mM and an IC90 dose of 160 mM. Topical eye drop treatment with 200 mM l-psicose in PBS solution significantly reduced the severity of HSK compared to the mock treatment group. The in vivo mouse ocular model results of l-psicose therapy correlated with accelerated clearance of virus from eye swabs. CONCLUSION: The results suggest that topical treatment with rare sugar l-psicose has efficacy against HSK through inhibition of HSV-1.


Assuntos
Antivirais/uso terapêutico , Frutose/uso terapêutico , Ceratite Herpética/tratamento farmacológico , Administração Tópica , Animais , Antivirais/administração & dosagem , Modelos Animais de Doenças , Olho/efeitos dos fármacos , Olho/virologia , Feminino , Frutose/administração & dosagem , Herpesvirus Humano 1 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
6.
Exp Eye Res ; 149: 100-106, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27344955

RESUMO

CD13/APN (aminopeptidase N) was first identified as a selective angiogenic marker expressed in tumor vasculature and is considered a target for anti-cancer therapy. CD13 was also reported to express in non-diabetic, hypoxia-induced retinal neovascularization. Whether diabetes induces upregulation of CD13 expression in the retina is unknown. We hypothesize that at an early stage of non-proliferative diabetic retinopathy (NPDR) characterized by disruption of blood-retinal barrier (BRB) permeability is related to upregulated expression of CD13 because of its known role in extracellular matrix (ECM) degradation. The purpose of this study is to evaluate the role of CD13/APN and the therapeutic efficacy of a CD13/APN inhibitor in a mouse model of streptozotocin-induced NPDR. Hyperglycemic C57Bl/6 mice 26 weeks after streptozotocin (STZ) injection were intravitreally injected with a sustained release formulation of CD13/APN inhibitor bestatin. At 15th day of post-bestatin treatment, mouse retinas were evaluated for vascular permeability by Evans blue dye extravasation assay, fluorescent angiography of retinal vascular permeability and leukostasis. Retinal protein extracts were analyzed by Western blot to determine the effects of bestatin treatment on the expression of CD13/APN related inflammatory mediators of ECM degradation and angiogenesis. Intravitreal bestatin treatment significantly inhibited retinal vascular permeability and leukostasis. This treatment also significantly inhibited retinal expression of CD13, ECM degrading proteases (heparanase and MMP9 and angiogenic molecules (HIF-1α and VEGF). Intravitreal CD13 inhibition may relate to furthering our knowledge on the protective effect of bestatin against diabetic retinal vasculature abnormalities through inhibition of retinal permeability, leukostasis, inflammatory molecules of ECM degradation and angiogenesis.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Leucina/análogos & derivados , Retina/efeitos dos fármacos , Animais , Western Blotting , Antígenos CD13/antagonistas & inibidores , Antígenos CD13/metabolismo , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/metabolismo , Relação Dose-Resposta a Droga , Angiofluoresceinografia , Fundo de Olho , Injeções Intravítreas , Leucina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Inibidores de Proteases/administração & dosagem , Retina/metabolismo , Retina/patologia
7.
Geosci Model Dev ; 9(5): 1905-1919, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29652411

RESUMO

The NOAA National Centers for Environmental Prediction (NCEP) implemented NEMS GFS Aerosol Component (NGAC) for global dust forecasting in collaboration with NASA Goddard Space Flight Center (GSFC). NGAC Version 1.0 has been providing 5 day dust forecasts at 1°×1° resolution on a global scale, once per day at 00:00 Coordinated Universal Time (UTC), since September 2012. This is the first global system capable of interactive atmosphere aerosol forecasting at NCEP. The implementation of NGAC V1.0 reflects an effective and efficient transitioning of NASA research advances to NCEP operations, paving the way for NCEP to provide global aerosol products serving a wide range of stakeholders as well as to allow the effects of aerosols on weather forecasts and climate prediction to be considered.

8.
Int J Climatol ; 35(14): 4262-4275, 2015 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27656043

RESUMO

Ranking the performance of global climate models (GCMs) is a notoriously difficult exercise. Multi-model comparison studies nearly always show that each model has strengths and weaknesses relative to others, and for many purposes the multi-model ensemble mean delivers better estimates than any individual model. Nevertheless, in regions like East Africa, where there is little consensus between models on the magnitude or sign of 21st century precipitation change, the multi-model ensemble mean approach to climate projection provides little value for adaptation planning. Here, we consider several possible frameworks for model evaluation and ranking, and assess the differences in performance of a subset of models participating in the 5th Coupled Model Intercomparison Project (CMIP5) according to each framework. Our test case is precipitation in the Nile River headwaters regions. We find that there is little consistency in the relative performance of models across frameworks based on amount and seasonality of precipitation, interannual precipitation variability, precipitation teleconnections, and continental scale climate patterns. These analyses offer some guidance on which GCMs are most likely to provide meaningful results for specific applications, but they caution that any effort to select 'best performing' GCMs for the Nile River basin must carefully consider the purposes for which GCMs are being selected.

9.
Antiviral Res ; 100(1): 14-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23860013

RESUMO

The amphoteric C31G solution contains equimolar alkyl dimethlyglycine and alkyl dimethyl amine oxide buffered with citric acid. C31G acts as a broad spectrum antiviral and an antibacterial. No previous in vivo studies have been done to test C31G in an animal model of HSV-1 ocular keratitis. We assessed the anti-herpetic activity of C31G in the rabbit eye model using three treatment groups: (1) 1% trifluorothymidine (TFT); (2) 0.25% C31G plus 0.5% hydroxypropyl methylcellulose (HPMC); and (3) vehicle, 0.5% HPMC. Scarified rabbit corneas were inoculated with the HSV-1 strain McKrae. On post inoculation (PI) day 3, rabbits were placed in three balanced groups based on slit-lamp examination (SLE) scores. Treatment began on PI day 3, five times a day for five consecutive days. In addition to the daily, masked SLE scoring, the eyes were assessed daily for stromal opacity, scleral inflammation, neovascularization, eyelid inflammation, inflammatory discharge, and epiphora. C31G and TFT were very effective in reducing the lesions and pathogenesis associated with HSV-1 ocular keratitis. The vehicle control scores were significantly higher and did not effectively treat HSV-1 keratitis. C31G has the potential to be used to treat herpetic keratitis as well as other herpetic topical lesions in humans.


Assuntos
Antivirais/administração & dosagem , Betaína/análogos & derivados , Ácidos Graxos Insaturados/administração & dosagem , Herpesvirus Humano 1/efeitos dos fármacos , Ceratite Herpética/tratamento farmacológico , Animais , Betaína/administração & dosagem , Córnea/patologia , Córnea/virologia , Modelos Animais de Doenças , Herpesvirus Humano 1/fisiologia , Humanos , Ceratite Herpética/patologia , Ceratite Herpética/virologia , Coelhos
10.
J Biomed Biotechnol ; 2012: 612316, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091352

RESUMO

The exact mechanisms of HSV-1 establishment, maintenance, latency, reactivation, and also the courses of recurrent ocular infections remain a mystery. Comprehensive understanding of the HSV-1 disease process could lead to prevention of HSV-1 acute infection, reactivation, and more effective treatments of recurrent ocular disease. Animal models have been used for over sixty years to investigate our concepts and hypotheses of HSV-1 diseases. In this paper we present descriptions and examples of rabbit and mouse eye models of HSV-1 latency, reactivation, and recurrent diseases. We summarize studies in animal models of spontaneous and induced HSV-1 reactivation and recurrent disease. Numerous stimuli that induce reactivation in mice and rabbits are described, as well as factors that inhibit viral reactivation from latency. The key features, advantages, and disadvantages of the mouse and rabbit models in relation to the study of ocular HSV-1 are discussed. This paper is pertinent but not intended to be all inclusive. We will give examples of key papers that have reported novel discoveries related to the review topics.


Assuntos
Infecções Oculares Virais/fisiopatologia , Infecções Oculares Virais/virologia , Herpes Simples/fisiopatologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Ativação Viral/fisiologia , Latência Viral/fisiologia , Animais , Modelos Animais de Doenças , Humanos , Coelhos , Recidiva , Especificidade da Espécie
11.
Virol J ; 9: 221, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23021094

RESUMO

BACKGROUND: Rabbits latent with HSV-1 strain McKrae spontaneously shed infectious virus and viral DNA into their tears and develop recurrent herpetic-specific corneal lesions. The rabbit eye model has been used for many years to assess acute ocular infections and pathogenesis, antiviral efficacy, as well as latency, reactivation, and recurrent eye diseases. This study used real-time PCR to quantify HSV-1 DNA in the saliva and tears of rabbits latent with HSV-1 McKrae. METHODS: New Zealand white rabbits used were latent with HSV-1 strain McKrae and had no ocular or oral pathology. Scarified corneas were topically inoculated with HSV-1. Eye swabs and saliva were taken from post inoculation (PI) days 28 through 49 (22 consecutive days). Saliva samples were taken four times each day from each rabbit and the DNA extracted was pooled for each rabbit for each day; one swab was taken daily from each eye and DNA extracted. Real-time PCR was done on the purified DNA samples for quantification of HSV-1 DNA copy numbers. Data are presented as copy numbers for each individual sample, plus all the copy numbers designated as positive, for comparison between left eye (OS), right eye (OD), and saliva. RESULTS: The saliva and tears were taken from 9 rabbits and from 18 eyes and all tested positive at least once. Saliva was positive for HSV-1 DNA at 43.4% (86/198) and tears were positive at 28.0% (111/396). The saliva positives had 48 episodes and the tears had 75 episodes. The mean copy numbers ± the SEM for HSV-1 DNA in saliva were 3773 ± 2019 and 2294 ± 869 for tears (no statistical difference). CONCLUSION: Rabbits latent with strain McKrae shed HSV-1 DNA into their saliva and tears. HSV-1 DNA shedding into the saliva was similar to humans. This is the first evidence that documents HSV-1 DNA in the saliva of latent rabbits.


Assuntos
DNA Viral/isolamento & purificação , Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Saliva/virologia , Latência Viral , Eliminação de Partículas Virais , Animais , Modelos Animais de Doenças , Herpesvirus Humano 1/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Lágrimas/virologia , Carga Viral
12.
PLoS One ; 7(12): e52152, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284911

RESUMO

Although the importance of human apolipoprotein E (apoE) in vascular diseases has clearly been established, most of the research on apoE has focused on its role in cholesterol metabolism. In view of the observation that apoE and its functional domains impact extracellular matrix (ECM) remodeling, we hypothesized that apoE could also confer protection against ECM degradation by mechanisms independent of its role in cholesterol and lipoprotein transport. The ECM degrading enzyme, heparanase, is secreted by cells as pro-heparanase that is internalized through low-density lipoprotein (LDL) receptor-related protein-1 (LRP-1) to become enzymatically active. Both apoE and pro-heparanase bind the LRP-1. We further hypothesized that an apoE mimetic peptide (apoEdp) would inhibit the production of active heparanase by blocking LRP-1-mediated uptake of pro-heparanase and thereby decrease degradation of the ECM. To test this hypothesis, we induced the expression of heparanase by incubating human retinal endothelial cells (hRECs) with high glucose (30 mM) for 72 hours. We found that elevated expression of heparanase by high glucose was associated with increased shedding of heparan sulfate (ΔHS) and the tight junction protein occludin. Treatment of hRECs with 100 µM apoEdp in the presence of high glucose significantly reduced the expression of heparanase, shedding of ΔHS, and loss of occludin as detected by Western blot analysis. Either eye drop treatment of 1% apoEdp topically 4 times a day for 14 consecutive days or intraperitoneal injection (40 mg/kg) of apoEdp daily for 14 consecutive days in an in vivo mouse model of streptozotocin-induced diabetes inhibited the loss of tight junction proteins occludin and zona occludin- 1 (ZO-1). These findings imply a functional relationship between apoE and endothelial cell matrix because the deregulation of these molecules can be inhibited by a short peptide derived from the receptor-binding region of apoE. Thus, strategies targeting ECM-degrading enzymes could be therapeutically beneficial for treating diabetic retinopathy.


Assuntos
Apolipoproteínas E/química , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Matriz Extracelular/metabolismo , Glucose/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Retina/citologia , Animais , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Proteínas de Junções Íntimas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Future Microbiol ; 6(8): 877-907, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21861620

RESUMO

Most humans are infected with herpes simplex virus (HSV) type 1 in early childhood and remain latently infected throughout life. While most individuals have mild or no symptoms, some will develop destructive HSV keratitis. Ocular infection with HSV-1 and its associated sequelae account for the majority of corneal blindness in industrialized nations. Neuronal latency in the peripheral ganglia is established when transcription of the viral genome is repressed (silenced) except for the latency-associated transcripts and microRNAs. The functions of latency-associated transcripts have been investigated since 1987. Roles have been suggested relating to reactivation, establishment of latency, neuronal protection, antiapoptosis, apoptosis, virulence and asymptomatic shedding. Here, we review HSV-1 latent infections, reactivation, recurrent disease and antiviral therapies for the ocular HSV diseases.


Assuntos
Herpesvirus Humano 1/patogenicidade , Ceratite Herpética/tratamento farmacológico , Ceratite Herpética/virologia , Ativação Viral , Latência Viral , Antivirais/uso terapêutico , Regulação Viral da Expressão Gênica , Humanos , Recidiva
14.
Cornea ; 30(3): 251-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21304287

RESUMO

PURPOSE: To present a review supporting and refuting evidence from mouse, rabbit, nonhuman primate, and human studies of herpes simplex virus type 1 (HSV-1) concerning corneal latency. METHODS: More than 50 research articles on HSV-1 published in peer-reviewed journals were examined. RESULTS: Infectious HSV-1 has been found in mouse denervated tissues and in tissues with negative cultures from the corresponding ganglion. However, the different mouse strains have shown varied responses to different strains of HSV, making it difficult to relate such findings to humans. Rabbit studies provide excellent evidence for HSV-1 corneal latency including data on HSV-1 migration from the cornea into the corneoscleral rim and on the distribution of HSV-1 DNA in the cornea. However, the available methods for the detection of infectious HSV-1 may not be sensitive enough to detect low-level infection. Infectious HSV-1 has been successfully isolated from the tears of nonhuman primates in the absence of detectable corneal lesions. The recurrence of corneal ulcers in nonhuman primates before the appearance of infectious HSV-1 in tears suggests that the origin of the HSV-1 is the cornea, rather than the trigeminal ganglion. Human studies presented evidence of both ganglion and corneal latency. CONCLUSIONS: Understanding HSV-1 disease progression and the possibility of corneal latency could lead to more effective treatments for herpetic keratitis. However, it is unlikely that operational latency in the cornea will be definitively proven unless a new method with higher sensitivity for the detection of infectious virus is developed.


Assuntos
Córnea/virologia , Reservatórios de Doenças/virologia , Herpesvirus Humano 1/fisiologia , Ceratite Herpética/virologia , Latência Viral , Animais , Córnea/inervação , Humanos , Macaca , Camundongos , Coelhos , Gânglio Trigeminal/virologia
15.
PLoS One ; 6(1): e15905, 2011 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-21253017

RESUMO

Angiogenesis is a hallmark of tumor development and metastasis and now a validated target for cancer treatment. We previously reported that a novel dimer peptide (apoEdp) derived from the receptor binding region of human apolipoprotein E (apoE) inhibits virus-induced angiogenesis. However, its role in tumor anti-angiogenesis is unknown. This study demonstrates that apoEdp has anti-angiogenic property in vivo through reduction of tumor growth in a mouse model and ocular angiogenesis in a rabbit eye model. Our in vitro studies show that apoEdp inhibits human umbilical vein endothelial cell proliferation, migration, invasion and capillary tube formation. We document that apoEdp inhibits vascular endothelial growth factor-induced Flk-1 activation as well as downstream signaling pathways that involve c-Src, Akt, eNOS, FAK, and ERK1/2. These in vitro data suggest potential sites of the apoE dipeptide inhibition that could occur in vivo.This is the first evidence that a synthetic dimer peptide mimicking human apoE has anti-angiogenesis functions and could be an anti-tumor drug candidate.


Assuntos
Antineoplásicos/química , Apolipoproteínas E/química , Proliferação de Células/efeitos dos fármacos , Olho/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Dipeptídeos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Olho/efeitos dos fármacos , Humanos , Camundongos , Coelhos , Veias Umbilicais
16.
Invest Ophthalmol Vis Sci ; 52(3): 1770-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20881297

RESUMO

PURPOSE: To determine host response by gene expression in HSV-1 latent trigeminal ganglia (TG) after sodium butyrate (NaBu) treatment. METHODS: Corneas of 6-week-old female BALB/c mice were scarified and inoculated with HSV-1 17Syn(+) (high phenotypic reactivator) or its mutant 17ΔPst(LAT(-)) (low phenotypic reactivator) at 10(4) plaque-forming units/eye. NaBu-induced viral reactivation was by intraperitoneal (IP) administration at postinfection (PI) day 28, followed by euthanasia after 1 hour. NaBu-treated, uninfected mice served as the control. The resultant labeled cRNA from TG isolated total RNA was hybridized to gene microarray chips containing 14,000 mouse genes. Quantitative real-time PCR was performed to confirm gene expression. RESULTS: Differential induction of gene expression between 17Syn(+) and its mutant 17ΔPst(LAT(-)) was designated as NaBu-induced gene expression and yielded significant upregulation of 2- to 16-fold of 0.4% (56/14,000) host genes probed, comprising mainly nucleosome assembly and binding, central nervous system structural activity, hormonal activity, and signaling activity. Approximately 0.2% (24/14,000) of the host genes, mainly of the same functional categories were downregulated 3- to 11-fold. Immune activity was minor in comparison to our reports on gene expression during latency and heat stress induction. Euchromatin analysis revealed that the LAT-ICP0 locus is amenable to the effects of NaBu. Histone activity was detected by early transcription of histone cluster 2 H2be (Hist2h2be). CONCLUSIONS NaBu-induced reactivation of HSV-1 is twofold: drug action involving significant moderation of specific host epigenetic changes and failure to elicit or suppress immune activity at the early time point of 1 hour.


Assuntos
Butiratos/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 1/genética , Proteínas Imediatamente Precoces/fisiologia , MicroRNAs/fisiologia , Gânglio Trigeminal/virologia , Ubiquitina-Proteína Ligases/fisiologia , Latência Viral/fisiologia , Animais , Córnea/inervação , Variações do Número de Cópias de DNA , DNA Viral/genética , Feminino , Herpesvirus Humano 1/fisiologia , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Nucleossomos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima , Ativação Viral/efeitos dos fármacos
17.
Invest Ophthalmol Vis Sci ; 52(2): 830-3, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20861476

RESUMO

PURPOSE: To determine whether trifluorothymidine (TFT) and ganciclovir (GCV) are synergistic against herpes simplex virus type 1 (HSV-1). METHODS: TFT and GCV activity against 12 strains of HSV-1 (including an acyclovir-resistant strain) was measured by plaque-forming unit (PFU) inhibition. Cellular toxicity was assessed with an MTT dye reduction assay. Synergism was determined by calculating fractional inhibitory concentration (FIC indices) based on PFU reduction. RESULTS: Concentrations of TFT resulting in 50% inhibition of PFUs (IC(50)) of acyclovir-susceptible HSV-1 strains ranged from 3.07 ± 0.36 to 12.52 ± 0.61 µM. GCV IC(50) values ranged from 0.40 ± 0.02 to 1.59 ± 0.14 µM. IC(50) values of TFT and GCV against the acyclovir-resistant strain were 15.40 ± 3.17 and 93.00 ± 9.64 µM, respectively. Concentrations of TFT or GCV resulting in 50% cell cytotoxicity (CC(50)) were 0.99 ± 0.01 and 92.91 ± 8.92 µM, respectively. TFT and GCV combined (10:1) were 10 times more potent against all acyclovir-susceptible HSV-1 strains. For 8 of 12 HSV-1 strains, the IC(50) of TFT and GCV combined was lower than the CC(50) of either drug. For acyclovir-susceptible HSV-1 strains, TFT and GCV combined generated a FIC index of <0.5, suggesting strong synergism between the two drugs. The FIC value for TFT and GCV combined against the acyclovir-resistant HSV-1 strain was 0.84, indicating nonantagonism. CONCLUSIONS: TFT and GCV are synergistic against acyclovir-susceptible HSV-1 at concentrations significantly less toxic than if each antiviral were used as a sole agent.


Assuntos
Antivirais/farmacologia , Ganciclovir/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Trifluridina/farmacologia , Animais , Chlorocebus aethiops , Sinergismo Farmacológico , Herpesvirus Humano 1/crescimento & desenvolvimento , Células Vero , Ensaio de Placa Viral , Cultura de Vírus
18.
Invest Ophthalmol Vis Sci ; 52(1): 339-44, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20702820

RESUMO

PURPOSE: To determine the efficacy of a new formulation of topical dexamethasone 0.1%/povidone-iodine 0.4% (FST-100) in reducing clinical symptoms and infectious viral titers in a rabbit model of adenoviral keratoconjunctivitis. METHODS: Rabbit corneas were inoculated bilaterally with 2×10(6) plaque-forming-units (PFU) of adenovirus type 5 (Ad5) after corneal scarification. Animals were randomized 1:1:1:1 (five rabbits per group) to FST-100, 0.5% cidofovir, tobramycin/dexamethasone (Tobradex; Alcon Laboratories, Fort Worth, TX) ophthalmic suspension, and balanced salt solution (BSS; Alcon Laboratories). Treatment began 12 hours after viral inoculation and continued for 7 consecutive days. The eyes were clinically scored daily for scleral inflammation (injection), ocular neovascularization, eyelid inflammation (redness), friability of vasculature, inflammatory discharge (pus), and epiphora (excessive tearing). Eye swabs were collected daily before treatment for the duration of the study. Virus was eluted from the swabs and PFU determined by titration on human A549 cells, according to standard procedures. RESULTS: The FST-100 treatment resulted in significantly lower clinical scores (P<0.05) than did the other treatments. The 0.5% cidofovir exhibited the most ocular toxicity compared with FST-100, tobramycin/dexamethasone, and balanced salt solution treatments. FST-100 and 0.5% cidofovir significantly (P<0.05) reduced viral titers compared with tobramycin/dexamethasone or balanced salt solution. CONCLUSIONS: FST-100 was the most efficacious in minimizing the clinical symptoms of adenovirus infection in rabbit eyes. FST-100 and 0.5% cidofovir were both equally effective in reducing viral titers and decreasing the duration of viral shedding. By providing symptomatic relief in addition to reducing infectious virus titers, FST-100 should be a valuable addition to treatment of epidemic adenoviral keratoconjunctivitis.


Assuntos
Infecções por Adenoviridae/tratamento farmacológico , Anti-Infecciosos Locais/uso terapêutico , Conjuntivite Viral/tratamento farmacológico , Dexametasona/uso terapêutico , Modelos Animais de Doenças , Soluções Oftálmicas/uso terapêutico , Povidona-Iodo/uso terapêutico , Adenoviridae/crescimento & desenvolvimento , Infecções por Adenoviridae/virologia , Animais , Cidofovir , Túnica Conjuntiva/virologia , Conjuntivite Viral/virologia , Citosina/análogos & derivados , Citosina/uso terapêutico , Quimioterapia Combinada , Organofosfonatos/uso terapêutico , Preparações Farmacêuticas , Coelhos , Tobramicina/uso terapêutico , Resultado do Tratamento , Ensaio de Placa Viral
19.
Neuroreport ; 21(14): 922-7, 2010 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-20683212

RESUMO

Human brains harbor herpes simplex virus type-1 (HSV-1) DNA, which normally remains quiescent throughout many decades of life. HSV-1 is associated with viral encephalopathy and with the amyloid beta 42 (Abeta42) peptide-enriched lesions that characterize Alzheimer's disease neuropathology. Here we report that infection of human neuronal-glial cells in primary co-culture with HSV-1 induces an irregular hypertrophy of human neuronal-glial cell bodies, an induction of HSV-1 DNA polymerase, and an up-regulation of micro-RNA-146a associated with altered innate-immune responses. Presence of the antiviral acyclovir or soluble Abeta42 peptide significantly attenuated these neuropathological responses. The inhibitory effects of Abeta42 peptide were also observed in an HSV-1-infected CV-1 cell-based viral plaque assay. The results suggest that soluble Abeta42 peptide can invoke non-pathological and anti-viral effects through inactivation of an HSV-1 challenge to human brain cells by simple viral sequestration, viral destruction, or by complex neurogenetic mechanisms.


Assuntos
Aciclovir/farmacologia , Peptídeos beta-Amiloides/farmacologia , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/genética , MicroRNAs/biossíntese , Fragmentos de Peptídeos/farmacologia , RNA Viral/biossíntese , Células Cultivadas , Técnicas de Cocultura , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Encefalite por Herpes Simples/tratamento farmacológico , Encefalite por Herpes Simples/genética , Encefalite por Herpes Simples/metabolismo , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/genética , Herpesvirus Humano 1/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/fisiologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/virologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
20.
Invest Ophthalmol Vis Sci ; 51(9): 4703-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20393107

RESUMO

PURPOSE: To assess the effect of high doses of valacyclovir (VCV) on HSV-1 DNA shedding into tears of latently infected rabbits. METHODS: Three oral doses of VCV were tested. Corneas were inoculated with HSV-1, and latent infection was allowed to establish. Starting on postinoculation (PI) day 28, tear swabs were collected once daily for 6 consecutive days before treatment. The rabbits were placed in five balanced groups: group 1 had no treatment, group 2 received placebo, group 3 received 7 mg/kg VCV, group 4 received 70 mg/kg, and group 5 received 140 mg/kg. The treatment was administered by oral gavage twice daily, starting on PI day 36 and continuing for 14 days. The ocular swabs were collected beginning on PI day 40 and continuing for 10 days. RESULTS: The mean copy number of HSV-1 DNA before treatment was 370+/-70, 569+/-273, 368+/-86, 408+/-108, and 396+/-91, and the mean HSV-1 DNA copy number after treatment was 232+/-183, 564+/-186, 518+/-122, 67+/-63, and 13+/-7 in groups 1 to 5, respectively. CONCLUSIONS: There was no observable toxicity in any group. The 70- and 140-mg/kg doses of VCV significantly reduced the HSV-1 DNA copy number, compared with that of the other three groups. A daily dose of 500 mg (approximately 7 mg/kg) VCV in healthy human volunteers did not suppress HSV-1 DNA shedding in tears and saliva. Thus, higher doses of VCV may be necessary to reduce asymptomatic shedding in healthy human subjects.


Assuntos
Aciclovir/análogos & derivados , Antivirais/farmacologia , Herpes Simples , Herpesvirus Humano 1/efeitos dos fármacos , Lágrimas/virologia , Valina/análogos & derivados , Aciclovir/farmacologia , Animais , DNA Viral/metabolismo , Relação Dose-Resposta a Droga , Dosagem de Genes , Herpes Simples/tratamento farmacológico , Herpes Simples/transmissão , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/crescimento & desenvolvimento , Coelhos , Lágrimas/efeitos dos fármacos , Valaciclovir , Valina/farmacologia , Latência Viral
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