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1.
J Patient Saf ; 20(3): 147-163, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372511

RESUMO

OBJECTIVES: Public awareness initiatives have attracted growing attention globally, as a strategy to reduce low-value care and disinformation. However, knowledge gap remains in determining their effects. The aim of this systematic review was to summarize existing evidence to date on global effectiveness of public awareness initiatives. METHODS: Primary quantitative studies focusing on passive delivery of public awareness initiatives that targeted health professionals were included. Eligible studies were identified through search of MEDLINE, Embase, Emcare, the Cochrane Library, PsycINFO, Business Source Complete, Emerald Insight, and Google (initially on December 19, 2018, followed by updated search between July 8-10, 2019, and then between March 8-9, 2022) and the reference list of relevant studies. Methodological quality of included studies was assessed using modified McMaster critical appraisal tool. A narrative synthesis of the study outcomes was conducted. RESULTS: Twenty studies from United States, United Kingdom, Canada, Australia, and multicountry were included. Nineteen studies focused on Choosing Wisely initiative and one focused on National Institute of Clinical Excellence reminders. Most studies investigated one recommendation of a specialty. The findings showed conflicting evidence on the effectiveness of public awareness initiatives, suggesting passive delivery has limited success in reducing low-value care among health professionals. CONCLUSIONS: This review highlights the complexity of change in an established practice pattern in health care. As passive delivery of public awareness initiatives has limited potential to initiate and sustain change, wide-ranging intervention components need to be integrated for a successful implementation.


Assuntos
Prática Clínica Baseada em Evidências , Educação em Saúde , Saúde Pública , Humanos , Pessoal de Saúde
2.
Biol Aujourdhui ; 216(3-4): 167-181, 2022.
Artigo em Francês | MEDLINE | ID: mdl-36744982

RESUMO

Immunotoxicology aims at studying toxic effects of any substance on the immune system and its functions. In its various fields of application, this science is dependent on regulatory texts and guidelines. Studies are based on in vitro, ex vivo and in vivo techniques and are observational or functional allowing the identification of a toxic effect and its underlying mechanisms, respectively. Here, we review the various tests to perform in biomedical research and development, with a particular interest for the T-cell Dependent Antibody Response (TDAR) assay. We also briefly discuss the upcoming evolutions in this domain within a more ethically sound framework such as limiting the use of laboratory animals. These evolutions are represented by the development of relevant cell models.


Title: Évaluation de l'immunotoxicité en recherche et dans le cadre du développement biomédical. Abstract: L'immunotoxicologie est l'étude des effets toxiques de toute substance sur le système immunitaire et ses fonctions. Dans les différents domaines d'application, cette science est cadrée par divers textes réglementaires et lignes directrices. Les études sont basées sur des techniques in vitro, ex vivo et in vivo et sont observationnelles ou fonctionnelles, permettant respectivement de démontrer un effet et de décrire les mécanismes en jeu. Dans cette revue, nous présentons les différents tests à effectuer dans le domaine biomédical, avec une attention particulière au test d'évaluation de la réponse thymo-dépendante (TDAR). Nous discutons également brièvement des évolutions à suivre dans ce domaine cherchant entre autres une approche plus éthique comme la limitation de l'utilisation des animaux de laboratoire. Ces évolutions sont notamment représentées par le développement de modèles cellulaires pertinents.


Assuntos
Sistema Imunitário , Testes de Toxicidade , Animais , Pesquisa Biomédica , Toxicologia
3.
ACS Nano ; 14(9): 11238-11253, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32692155

RESUMO

Although cytokine therapy is an attractive strategy to build a more robust immune response in tumors, cytokines have faced clinical failures due to toxicity. In particular, interleukin-12 has shown great clinical promise but was limited in translation because of systemic toxicity. In this study, we demonstrate an enhanced ability to reduce toxicity without affecting the efficacy of IL-12 therapy. We engineer the material properties of a NP to meet the enhanced demands for optimal cytokine delivery by using the layer-by-layer (LbL) approach. Importantly, using LbL, we demonstrate cell-level trafficking of NPs to preferentially localize to the cell's outer surface and act as a drug depot, which is required for optimal payload activity on neighboring cytokine membrane receptors. LbL-NPs showed efficacy against a tumor challenge in both colorectal and ovarian tumors at doses that were not tolerated when administered carrier-free.


Assuntos
Nanopartículas , Neoplasias , Citocinas , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias/tratamento farmacológico
4.
Int J Behav Nutr Phys Act ; 16(1): 123, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805972

RESUMO

BACKGROUND: Despite the ongoing promotion of physical activity, the rates of physical inactivity remain high. Drawing on established methods of analysing consumer behaviour, this study seeks to understand how physical activity competes for finite time in a day - how Exercise and Sport compete with other everyday behaviours, and how engagement in physical activity is shared across Exercise and Sport activities. As targeted efforts are common in physical activity intervention and promotion, the existence of segmentation is also explored. METHODS: Time-use recall data (n = 2307 adults) is analysed using the Duplication of Behaviour Law, and tested against expected values, to document what proportion of the population that engage in one activity, also engage in another competing activity. Additionally, a Mean Absolute Deviation approach is used to test for segmentation. RESULTS: The Duplication of Behaviour Law is evident for everyday activities, and Exercise and Sport activities - all activities 'compete' with each other, and the prevalence of the competing activity determines the extent of competition. However, some activities compete more or less than expected, suggesting the combinations of activities that should be used or avoided in promotion efforts. Competition between everyday activities is predictable, and there are no specific activities that are sacrificed to engage in Exercise and Sport. How people share their physical activity across different Exercise and Sport activities is less predictable - Males and younger people (under 20 years) are more likely to engage in Exercise and Sport, and those who engage in Exercise and Sport are slightly more likely to Work and Study. High competition between Team Sports and Non-Team Sports suggests strong preferences for sports of different varieties. Finally, gender and age-based segmentation does not exist for Exercise and Sport relative to other everyday activities; however, segmentation does exist for Team Sports, Games, Active Play and Dance. CONCLUSIONS: The Duplication of Behaviour Law demonstrates that population-level patterns of behaviour can yield insight into the competition between different activities, and how engagement in physical activity is shared across different Exercise and Sport activities. Such insights can be used to describe and predict physical activity behaviour and may be used to inform and evaluate promotion and intervention.


Assuntos
Comportamento Competitivo , Exercício Físico , Esportes , Adulto , Feminino , Humanos , Masculino , Esportes/fisiologia , Esportes/estatística & dados numéricos , Adulto Jovem
5.
Nat Rev Clin Oncol ; 16(1): 45-63, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30082906

RESUMO

In 2017, an autologous chimeric antigen receptor (CAR) T cell therapy indicated for children and young adults with relapsed and/or refractory CD19+ acute lymphoblastic leukaemia became the first gene therapy to be approved in the USA. This innovative form of cellular immunotherapy has been associated with remarkable response rates but is also associated with unique and often severe toxicities, which can lead to rapid cardiorespiratory and/or neurological deterioration. Multidisciplinary medical vigilance and the requisite health-care infrastructure are imperative to ensuring optimal patient outcomes, especially as these therapies transition from research protocols to standard care. Herein, authors representing the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network Hematopoietic Stem Cell Transplantation (HSCT) Subgroup and the MD Anderson Cancer Center CAR T Cell Therapy-Associated Toxicity (CARTOX) Program have collaborated to provide comprehensive consensus guidelines on the care of children receiving CAR T cell therapy.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunoterapia Adotiva/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Lesão Pulmonar Aguda/induzido quimicamente , Criança , Humanos , Guias de Prática Clínica como Assunto , Adulto Jovem
6.
Invest Ophthalmol Vis Sci ; 59(12): 5157-5166, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30372742

RESUMO

Purpose: The purpose of this study was to measure the full-field deformation response to IOP change in the peripapillary sclera (PPS) and astrocytic lamina cribrosa (ALC) of young and old mouse eyes ex vivo. Methods: Thirty-eight transgenic reporter mice with green fluorescent protein-expressing astrocytes were studied at 2 to 4 months and 13 to 15 months old. The ALC and PPS of the explant eyes were imaged using laser scanning microscopy under controlled inflation from 10 to 30 mm Hg. Strains were estimated for the ALC and PPS from imaged volumes using digital volume correlation. Results: ALC strains were significantly greater than zero nasal-temporally for both age groups (mean = 4.3% and 4.0%; each P ≤ 0.004) and significantly greater than zero in the inferior-superior direction for younger mice (P = 0.0004). Younger mice had larger ALC inferior-superior strains than older mice (P = 0.002). The ALC area and perimeter enlarged with inflation in both age groups, with a greater increase in younger than in older mice (all P ≤ 0.004). The ALC nasal-temporal diameter change was greater than inferior-superiorly, and younger mice had greater enlargement nasal-temporally than older. PPS maximum shear strain was greater in the older mice (P = 0.002). The axial lengths of older mice were 14% longer and the PPS was 16% thinner than younger mice (both P = 0.0003). Conclusions: The behavior of the ALC in younger mice with inflation exhibited greater strains and enlargement of ALC area than older mice. Some strain measures in the PPS were greater in older mice, likely related to their longer axial length and thinner PPS.


Assuntos
Envelhecimento/fisiologia , Astrócitos/fisiologia , Disco Óptico/fisiopatologia , Esclera/fisiologia , Animais , Comprimento Axial do Olho/patologia , Fenômenos Biomecânicos , Proteínas de Fluorescência Verde/metabolismo , Pressão Intraocular/fisiologia , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Animais
7.
Exp Eye Res ; 172: 78-85, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29625080

RESUMO

The purpose of this study was to compare younger and older mice after chronic intraocular pressure (IOP) elevation lasting up to 4 days with respect to mitochondrial density, structure, and movement, as well as axonal integrity, in an ex vivo explant model. We studied 2 transgenic mouse strains, both on a C57BL/6J background, one expressing yellow fluorescent protein (YFP) in selected axons and one expressing cyan fluorescent protein (CFP) in all mitochondria. Mice of 4 months or 14 months of age were exposed to chronic IOP by anterior chamber microbead injection for 14 h, 1, 3, or 4 days. The optic nerve head of globe--optic nerve explants were examined by laser scanning microscopy. Mitochondrial density, structure, and movement were quantified in the CFP explants, and axonal integrity was quantified in YFP explants. In control mice, there was a trend towards decreased mitochondrial density (# per mm2) with age when comparing younger to older, control mice, but this was not significant (1947 ±â€¯653 vs 1412 ±â€¯356; p = 0.19). Mitochondrial density decreased after IOP elevation, significantly, by 31%, in younger mice (p = 0.04) but trending towards a decrease, by 22%, in older mice (p = 0.82) compared to age matched controls. Mitochondrial mean size was not altered after chronic IOP elevation for 14 h or more (p ≥ 0.16). When assessing mitochondrial movement, in younger mice, 5% were mobile at any given time; 4% in the anterograde direction and 1% retrograde. In younger untreated tissue, only 75% of explants had moving mitochondria (mean = 15.8 moving/explant), while after glaucoma induction only 24% of explants had moving mitochondria (mean = 4.2 moving/explant; difference from control, p = 0.03). The distance mitochondria traveled in younger mice was unchanged after glaucoma exposure, but in older glaucoma explants the distance traveled was less than half of older controls (p < 0.0003). In younger mice, mitochondrial speed increased after 14 h of elevated IOP (p = 0.006); however, in older glaucoma explants, movement was actually slower than controls (p = 0.02). In RGC-YFP explants, axonal integrity declined significantly after 4 days of IOP elevation to a similar degree in both younger and older mice. Older mice underwent greater loss of mitochondrial movement with chronic IOP elevation than younger mice, but suffered similar short-term axonal fragmentation in C57BL/6J mice. These transgenic strains, studied in explants, permit observations of alterations in intracellular structure and organelle activity in experimental glaucoma.


Assuntos
Transporte Axonal/fisiologia , Axônios/patologia , Pressão Intraocular/fisiologia , Mitocôndrias/patologia , Hipertensão Ocular/patologia , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Fatores Etários , Animais , Proteínas de Bactérias/metabolismo , Doença Crônica , Modelos Animais de Doenças , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Células Ganglionares da Retina/metabolismo , Tonometria Ocular
8.
Invest Ophthalmol Vis Sci ; 58(5): 2765-2773, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28549091

RESUMO

Purpose: To determine if retinal ganglion cell (RGC) axon loss in experimental mouse glaucoma is uniform in the optic nerve. Methods: Experimental glaucoma was induced for 6 weeks with a microbead injection model in CD1 (n = 78) and C57BL/6 (B6, n = 68) mice. From epoxy-embedded sections of optic nerve 1 to 2 mm posterior to the globe, total nerve area and regional axon density (axons/1600 µm2) were measured in superior, inferior, nasal, and temporal zones. Results: Control eyes of CD1 mice have higher axon density and more total RGCs than control B6 mice eyes. There were no significant differences in control regional axon density in all mice or by strain (all P > 0.2, mixed model). Exposure to elevated IOP caused loss of RGC in both strains. In CD1 mice, axon density declined without significant loss of nerve area, while B6 mice had less density loss, but greater decrease in nerve area. Axon density loss in glaucoma eyes was not significantly greater in any region in either mouse strain (both P > 0.2, mixed model). In moderately damaged CD1 glaucoma eyes, and CD1 eyes with the greatest IOP elevation exposure, density loss differed by region (P = 0.05, P = 0.03, mixed model) with the greatest loss in the temporal and superior regions, while in severely injured B6 nerves superior loss was greater than inferior loss (P = 0.01, mixed model, Bonferroni corrected). Conclusions: There was selectively greater loss of superior and temporal optic nerve axons of RGCs in mouse glaucoma at certain stages of damage. Differences in nerve area change suggest non-RGC responses differ between mouse strains.


Assuntos
Apoptose , Axônios/patologia , Modelos Animais de Doenças , Glaucoma/patologia , Doenças do Nervo Óptico/patologia , Células Ganglionares da Retina/patologia , Animais , Contagem de Células , Pressão Intraocular , Camundongos , Camundongos Endogâmicos C57BL , Disco Óptico/patologia
9.
Exp Eye Res ; 160: 106-115, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28414059

RESUMO

We developed an explant model of the mouse eye and optic nerve that facilitates the study of retinal ganglion cell axons and mitochondria in the living optic nerve head (ONH) in an ex vivo environment. Two transgenic mouse strains were used, one expressing yellow fluorescent protein in selected axons and a second strain expressing cyan fluorescent protein in all mitochondria. We viewed an explanted mouse eye and optic nerve by laser scanning microscopy at and behind the ONH, the site of glaucoma injury. Explants from previously untreated mice were studied with the intraocular pressure (IOP) set artificially at normal or elevated levels for several hours. Explants were also studied from eyes that had undergone chronic IOP elevation from 14 h to 6 weeks prior to ex vivo study. Image analysis in static images and video of individual mitochondria or axonal structure determined effects of acute and chronic IOP elevation. At normal IOP, fluorescent axonal structure was stable for up to 3 h under ex vivo conditions. After chronic IOP elevation, axonal integrity index values indicated fragmentation of axon structure in the ONH. In mice with fluorescent mitochondria, the normal density decreased with distance behind the ONH by 45% (p = 0.002, t-test). Density increased with prior chronic IOP elevation to 21,300 ± 4176 mitochondria/mm2 compared to control 16,110 ± 3159 mitochondria/mm2 (p = 0.025, t-test), but did not increase significantly after 4 h, acute IOP elevation (1.5% decrease in density, p = 0.83, t-test). Mean normal mitochondrial length of 2.3 ± 1.4 µm became 13% smaller after 4 h of IOP elevation ex vivo compared to baseline (p = 0.015, t-test, N-10). Normal mitochondrial speed of movement was significantly slower in the anterograde direction (towards the brain) than retrograde, but there were more mitochondria in motion and traveling longer lengths in anterograde direction. The percent of mitochondria in motion decreased by >50% with acute IOP increase to 30 mm Hg after 60 min. A new ocular explant model implemented with eyes from transgenic mice with fluorescent cellular components provided real time measurement of the early events in experimental glaucoma and quantitative outcomes for neuroprotection therapy experiments.


Assuntos
Axônios/patologia , Glaucoma/patologia , Pressão Intraocular/fisiologia , Mitocôndrias/patologia , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Doença Aguda , Animais , Doença Crônica , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Tonometria Ocular
10.
Invest Ophthalmol Vis Sci ; 58(2): 721-733, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28146237

RESUMO

Purpose: To develop an ex vivo explant system using multiphoton microscopy and digital volume correlation to measure the full-field deformation response to intraocular pressure (IOP) change in the peripapillary sclera (PPS) and in the optic nerve head (ONH) astrocytic structure. Methods: Green fluorescent protein (GFP)-glutamate transporter-GLT1 (GLT1/GFP) mouse eyes were explanted and imaged with a laser-scanning microscope under controlled inflation. Images were analyzed for regional strains and changes in astrocytic lamina and PPS shape. Astrocyte volume fraction in seven control GLT1/GFP mice was measured. The level of fluorescence of GFP fluorescent astrocytes was compared with glial fibrillary acidic protein (GFAP) labeled astrocytes using immunohistochemistry. Results: The ONH astrocytic structure remained stable during 3 hours in explants. Control strain-globally, in the central one-half or two-thirds of the astrocytic lamina-was significantly greater in the nasal-temporal direction than in the inferior-superior or anterior-posterior directions (each P≤ 0.03, mixed models). The PPS opening (perimeter) in normal eye explants also became wider nasal-temporally than superior-inferiorly during inflation from 10 to 30 mm Hg (P = 0.0005). After 1 to 3 days of chronic IOP elevation, PPS area was larger than in control eyes (P = 0.035), perimeter elongation was 37% less than controls, and global nasal-temporal strain was significantly less than controls (P = 0.007). Astrocyte orientation was altered by chronic IOP elevation, with processes redirected toward the longitudinal axis of the optic nerve. Conclusions: The explant inflation test measures the strain response of the mouse ONH to applied IOP. Initial studies indicate regional differences in response to both acute and chronic IOP elevation within the ONH region.


Assuntos
Astrócitos/fisiologia , Pressão Intraocular/fisiologia , Hipertensão Ocular/fisiopatologia , Disco Óptico/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Esclera/fisiopatologia , Animais , Astrócitos/patologia , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Masculino , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica , Disco Óptico/citologia
11.
J Pain ; 18(2): 200-211, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27838498

RESUMO

The purpose of this randomized noninferiority trial was to compare video teleconferencing (VTC) versus in-person (IP) delivery of an 8-week acceptance and commitment therapy (ACT) intervention among veterans with chronic pain (N = 128) at post-treatment and at 6-month follow-up. The primary outcome was the pain interference subscale of the Brief Pain Inventory. Secondary outcomes included measures of pain severity, mental and physical health-related quality of life, pain acceptance, activity level, depression, pain-related anxiety, and sleep quality. In intent to treat analyses using mixed linear effects modeling, both groups exhibited significant improvements on primary and secondary outcomes, with the exception of sleep quality. Further, improvements in activity level at 6-month follow-up were significantly greater in the IP group. The noninferiority hypothesis was supported for the primary outcome and several secondary outcomes. Treatment satisfaction was similar between groups; however, significantly more participants withdrew during treatment in the VTC group compared with the IP group, which was moderated by activity level at baseline. These findings generally suggest that ACT delivered via VTC can be as effective and acceptable as IP delivery for chronic pain. Future studies should examine the optimal delivery of ACT for patients with chronic pain who report low levels of activity. This trial was registered at ClinicalTrials.gov (NCT01055639). PERSPECTIVE: This study suggests that ACT for chronic pain can be implemented via VTC with reductions in pain interference comparable with IP delivery. This article contains potentially important information for clinicians using telehealth technology to deliver psychosocial interventions to individuals with chronic pain.


Assuntos
Terapia de Aceitação e Compromisso/métodos , Dor Crônica/psicologia , Dor Crônica/reabilitação , Telemedicina/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/etiologia , Ansiedade/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Comunicação por Videoconferência
12.
PLoS One ; 10(10): e0141137, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26505191

RESUMO

PURPOSE: To determine if oral losartan treatment decreases the retinal ganglion cell (RGC) death caused by experimental intraocular pressure (IOP) elevation in mice. METHODS: We produced IOP increase in CD1 mice and performed unilateral optic nerve crush. Mice received oral losartan, spironolactone, enalapril, or no drug to test effects of inhibiting angiotensin receptors. IOP was monitored by Tonolab, and blood pressure was monitored by tail cuff device. RGC loss was measured in masked axon counts and RGC bodies by ß-tubulin labeling. Scleral changes that could modulate RGC injury were measured including axial length, scleral thickness, and retinal layer thicknesses, pressure-strain behavior in inflation testing, and study of angiotensin receptors and pathways by reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry. RESULTS: Losartan treatment prevented significant RGC loss (median loss = 2.5%, p = 0.13), while median loss with water, spironolactone, and enalapril treatments were 26%, 28% and 43%; p < 0.0001). The lower RGC loss with losartan was significantly less than the loss with spironolactone or enalapril (regression model p = 0.001; drug treatment group term p = 0.01). Both losartan and enalapril significantly lowered blood pressure (p< 0.001), but losartan was protective, while enalapril led to worse than water-treated RGC loss. RGC loss after crush injury was unaffected by losartan treatment (difference from control p = 0.9). Survival of RGC in cell culture was not prolonged by sartan treatment. Axonal transport blockade after 3 day IOP elevations was less in losartan-treated than in control glaucoma eyes (p = 0.007). Losartan inhibited effects of glaucoma, including reduction in extracellular signal-related kinase activity and modification of glaucoma-related changes in scleral thickness and creep under controlled IOP. CONCLUSIONS: The neuroprotective effect of losartan in mouse glaucoma is associated with adaptive changes in the sclera expressed at the optic nerve head.


Assuntos
Glaucoma/tratamento farmacológico , Losartan/administração & dosagem , Células Ganglionares da Retina/efeitos dos fármacos , Esclera/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Glaucoma/patologia , Humanos , Pressão Intraocular/efeitos dos fármacos , Camundongos , Fármacos Neuroprotetores/administração & dosagem , Disco Óptico/efeitos dos fármacos , Disco Óptico/patologia , Retina/efeitos dos fármacos , Retina/patologia , Células Ganglionares da Retina/patologia , Esclera/patologia
13.
Syst Biol Reprod Med ; 61(3): 139-49, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25821920

RESUMO

Spermatozoa contain a complex population of RNAs including messenger RNAs (mRNAs) and small RNAs such as microRNAs (miRNA). It has been reported that these RNAs can be used to understand the mechanisms by which toxicological exposure affects spermatogenesis. The aim of our study was to compare mRNA and miRNA profiles in spermatozoa from eight smokers and eight non-smokers, and search for potential relationships between mRNA and miRNA variation. All men were selected based on their answers to a standard toxic exposure questionnaire, and sperm parameters. Using mRNA and miRNA microarrays, we showed that mRNAs from 15 genes were differentially represented between smokers and non-smokers (p<0.01): five had higher levels and 10 lower levels in the smokers. For the microRNAs, 23 were differentially represented: 16 were higher and seven lower in the smokers (0.004≤p<0.01). Quantitative RT-PCR confirmed the lower levels in smokers compared to non-smokers for hsa-miR-296-5p, hsa-miR-3940, and hsa-miR-520d-3p. Moreover, we observed an inverse relationship between the levels of microRNAs and six potential target mRNAs (B3GAT3, HNRNPL, OASL, ODZ3, CNGB1, and PKD2). Our results indicate that alterations in the level of a small number of microRNAs in response to smoking may contribute to changes in mRNA expression in smokers. We conclude that large-scale analysis of spermatozoa RNAs can be used to help understand the mechanisms by which human spermatogenesis responds to toxic substances including those in tobacco smoke.


Assuntos
MicroRNAs/metabolismo , Nicotiana , RNA Mensageiro/metabolismo , Fumar , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Humanos , Masculino , Espermatozoides/metabolismo
14.
Exp Eye Res ; 128: 129-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25285424

RESUMO

The purpose of this study was to assess the effect of a scleral cross-linking agent on susceptibility to glaucoma damage in a mouse model.CD1 mice underwent 3 subconjunctival injections of 0.5 M glyceraldehyde (GA) in 1 week, then had elevated intraocular pressure (IOP) induced by bead injection. Degree of cross-linking was measured by enzyme-linked immunosorbent assay (ELISA), scleral permeability was measured by fluorescence recovery after photobleaching (FRAP), and the mechanical effects of GA exposure were measured by inflation testing. Control mice had buffer injection or no injection in 2 separate glaucoma experiments. IOP was monitored by Tonolab and retinal ganglion cell (RGC) loss was measured by histological axon counting. To rule out undesirable effects of GA, we performed electroretinography and detailed histology of the retina. GA exposure had no detectable effects on RGC number, retinal structure or function either histologically or electrophysiologically. GA increased cross-linking of sclera by 37% in an ELISA assay, decreased scleral permeability (FRAP, p = 0.001), and produced a steeper pressure-strain behavior by in vitro inflation testing. In two experimental glaucoma experiments, GA-treated eyes had greater RGC axon loss from elevated IOP than either buffer-injected or control eyes, controlling for level of IOP exposure over time (p = 0.01, and 0.049, multivariable regression analyses). This is the first report that experimental alteration of the sclera, by cross-linking, increases susceptibility to RGC damage in mice.


Assuntos
Axônios/patologia , Reagentes de Ligações Cruzadas/toxicidade , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Gliceraldeído/toxicidade , Células Ganglionares da Retina/patologia , Esclera/efeitos dos fármacos , Animais , Elasticidade/efeitos dos fármacos , Eletrorretinografia , Ensaio de Imunoadsorção Enzimática , Proteínas do Olho/metabolismo , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Pressão Intraocular/efeitos dos fármacos , Camundongos , Permeabilidade , Esclera/metabolismo , Esclera/patologia , Tonometria Ocular
15.
Exp Eye Res ; 119: 54-60, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24368172

RESUMO

The purpose of this research was to study the effects of age and genetic alterations in key connective tissue proteins on susceptibility to experimental glaucoma in mice. We used mice haploinsufficient in the elastin gene (EH) and mice without both alleles of the fibromodulin gene (FM KO) and their wild type (WT) littermates of B6 and CD1 strains, respectively. FM KO mice were tested at two ages: 2 months and 12 months. Intraocular pressure (IOP) was measured by Tonolab tonometer, axial lengths and widths measured by digital caliper post-enucleation, and chronic glaucoma damage was measured using a bead injection model and optic nerve axon counts. IOP in EH mice was not significantly different from WT, but FM KO were slightly lower than their controls (p = 0.04). Loss of retinal ganglion cell (RGC) axons was somewhat, but not significantly greater in young EH and younger or older FM KO strains than in age-matched controls (p = 0.48, 0.34, 0.20, respectively, multivariable regression adjusting for IOP exposure). Older CD1 mice lost significantly more RGC axons than younger CD1 (p = 0.01, multivariable regression). The CD1 mouse strain showed age-dependence of experimental glaucoma damage to RGC in the opposite, and more expected, direction than in B6 mice in which older mice are more resistant to damage. Genetic alteration in two genes that are constituents of sclera, fibromodulin and elastin do not significantly affect RGC loss.


Assuntos
Envelhecimento/genética , Tecido Conjuntivo/metabolismo , DNA/genética , Proteínas do Olho/genética , Predisposição Genética para Doença , Glaucoma/genética , Mutação , Animais , Axônios/patologia , Fenômenos Biomecânicos , Contagem de Células , Tecido Conjuntivo/patologia , Modelos Animais de Doenças , Elastina/genética , Elastina/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Olho/metabolismo , Fibromodulina , Glaucoma/metabolismo , Glaucoma/fisiopatologia , Pressão Intraocular , Camundongos , Camundongos Knockout , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Proteoglicanas/genética , Proteoglicanas/metabolismo , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Esclera/metabolismo , Esclera/patologia , Esclera/fisiopatologia
16.
Mol Vis ; 19: 2023-39, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146537

RESUMO

PURPOSE: To study changes in scleral structure induced by chronic experimental intraocular pressure elevation in mice. METHODS: We studied the effect of chronic bead-induced glaucoma on scleral thickness, collagen lamellar structure, and collagen fibril diameter distribution in C57BL/6 (B6) and CD1 mice, and in collagen 8α2 mutant mice (Aca23) and their wild-type littermates (Aca23-WT) using electron and confocal microscopy. RESULTS: In unfixed tissue, the control B6 peripapillary sclera was thicker than in CD1 mice (p<0.001). After 6 weeks of glaucoma, the unfixed CD1 and B6 sclera thinned by 9% and 12%, respectively (p<0.001). The fixed sclera, measured by electron microscopy, was significantly thicker in control Aca23 than in B6 or CD1 mice (p<0.05). The difference between fresh and fixed scleral thickness was nearly 68% in untreated control B6 and CD1 mice, but differed by only 10% or less in fresh/fixed glaucoma scleral comparisons. There were 39.3±9.6 lamellae (mean, standard deviation) in control sclera, categorized as 41% cross-section, 24% cellular, 20% oblique, and 15% longitudinal. After glaucoma, mean peripapillary thickness significantly increased in fixed specimens of all mouse strains by 10.3 ±4.8 µm (p=0.001) and the total number of lamellae increased by 18% (p=0.01). The number of cellular and cross-section lamellae increased in glaucoma eyes. After glaucoma, there were more small and fewer large collagen fibrils (p<0.0001). Second harmonic generation imaging showed that the normal circumferential pattern of collagen fibrils in the peripapillary sclera was altered in significantly damaged glaucomatous eyes. CONCLUSIONS: Dynamic responses of the sclera to experimental mouse glaucoma may be more important than baseline anatomic features in explaining susceptibility to damage. These include decreases in nonfibrillar elements, alterations in lamellar orientation, an increased number of smaller collagen fibrils and fewer larger fibrils, and relative increase in the number of scleral fibroblast layers.


Assuntos
Pressão Intraocular , Esclera/patologia , Esclera/fisiopatologia , Animais , Axônios/patologia , Axônios/ultraestrutura , Doença Crônica , Colágeno/metabolismo , Modelos Animais de Doenças , Glaucoma/patologia , Glaucoma/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Regressão , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/ultraestrutura , Esclera/ultraestrutura
17.
J Nutr ; 143(4): 500-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23390191

RESUMO

Folate and vitamin B-12 are important for nervous system functioning at all ages, with important roles in functions such as neurotransmitter synthesis. Although studies suggest a relation between folate and vitamin B-12 and cognitive function in the elderly population, there is relatively less evidence regarding these vitamins and children's cognitive function. The purpose of the study was to examine the associations of serum folate and vitamin B-12 with cognitive performance in children 6-16 y old in the NHANES III, conducted from 1988 to 1994, prior to the implementation of folic acid fortification. A cross-sectional analysis was conducted using data on 5365 children 6-16 y old from NHANES III. Serum folate and vitamin B-12 concentrations were measured, along with performance, on the Wide Range Achievement Test-Revised and the Wechsler Intelligence Scale for Children-Revised. Associations of B vitamins with cognitive performance were assessed using linear regression models adjusted for various covariates. Higher serum concentrations of folate were associated with higher reading and block design scores after adjusting for various covariates. For example, compared with the lowest quartile of folate, children in the highest quartile scored 3.28 points or 0.19 SD units higher on the reading test (P < 0.05). Vitamin B-12 was not associated with any of the test scores. In the largest study to date, higher folate concentrations were associated with better reading and block design scores. These associations appear to be biologically plausible and merit further study.


Assuntos
Cognição/fisiologia , Ácido Fólico/sangue , Vitamina B 12/sangue , Adolescente , Criança , Estudos Transversais , Etnicidade , Feminino , Humanos , Renda , Masculino , Análise Multivariada , Inquéritos Nutricionais , Fatores Sexuais , Escalas de Wechsler
18.
Invest Ophthalmol Vis Sci ; 54(3): 1767-80, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23404116

RESUMO

PURPOSE: To study anatomical changes and mechanical behavior of the sclera in mice with experimental glaucoma by comparing CD1 to B6 mice. METHODS: Chronic experimental glaucoma for 6 weeks was produced in 2- to 4-month-old CD1 (43 eyes) and B6 mice (42 eyes) using polystyrene bead injection into the anterior chamber with 126 control CD1 and 128 control B6 eyes. Intraocular pressure (IOP) measurements were made with the TonoLab at baseline and after bead injection. Axial length and scleral thickness were measured after sacrifice in the CD1 and B6 animals and compared to length data from 78 eyes of DBA/2J mice. Inflation testing of posterior sclera was conducted, and circumferential and meridional strain components were determined from the displacement response. RESULTS: Experimental glaucoma led to increases in axial length and width by comparison to fellow eyes (6% in CD1 and 10% in B6; all P < 0.03). While the peripapillary sclera became thinner in both mouse types with glaucoma, the remainder of the sclera uniformly thinned in CD1, but thickened in B6. Peripapillary sclera in CD1 controls had significantly greater temporal meridional strain than B6 and had differences in the ratios of meridional to effective circumferential strain from B6 mice. In both CD1 and B6 mice, exposure to chronic IOP elevation resulted in stiffer pressure-strain responses for both the effective circumferential and meridional strains (multivariable regression model, P = 0.01-0.03). CONCLUSIONS: Longer eyes, greater scleral strain in some directions at baseline, and generalized scleral thinning after glaucoma were characteristic of CD1 mice that have greater tendency to retinal ganglion cell damage than B6 mice. Increased scleral stiffness after glaucoma exposure in mice mimics findings in monkey and human glaucoma eyes.


Assuntos
Apoptose , Fenômenos Biomecânicos/fisiologia , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Células Ganglionares da Retina/patologia , Esclera/fisiopatologia , Animais , Comprimento Axial do Olho/patologia , Axônios/patologia , Suscetibilidade a Doenças , Elasticidade , Pressão Intraocular/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Tonometria Ocular
19.
PLoS Pathog ; 8(11): e1003052, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209420

RESUMO

Bacterial biofilm is considered as a particular lifestyle helping cells to survive hostile environments triggered by a variety of signals sensed and integrated through adequate regulatory pathways. Pseudomonas aeruginosa, a Gram-negative bacterium causing severe infections in humans, forms biofilms and is a fantastic example for fine-tuning of the transition between planktonic and community lifestyles through two-component systems (TCS). Here we decipher the regulon of the P. aeruginosa response regulator PprB of the TCS PprAB. We identified genes under the control of this TCS and once this pathway is activated, analyzed and dissected at the molecular level the PprB-dependent phenotypes in various models. The TCS PprAB triggers a hyper-biofilm phenotype with a unique adhesive signature made of BapA adhesin, a Type 1 secretion system (T1SS) substrate, CupE CU fimbriae, Flp Type IVb pili and eDNA without EPS involvement. This unique signature is associated with drug hyper-susceptibility, decreased virulence in acutely infected flies and cytotoxicity toward various cell types linked to decreased Type III secretion (T3SS). Moreover, once the PprB pathway is activated, decreased virulence in orally infected flies associated with enhanced biofilm formation and dissemination defect from the intestinal lumen toward the hemolymph compartment is reported. PprB may thus represent a key bacterial adaptation checkpoint of multicellular and aggregative behavior triggering the production of a unique matrix associated with peculiar antibiotic susceptibility and attenuated virulence, a particular interesting breach for therapeutic intervention to consider in view of possible eradication of P. aeruginosa biofilm-associated infections.


Assuntos
Adesinas Bacterianas/metabolismo , Sistemas de Secreção Bacterianos/fisiologia , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia , Adesinas Bacterianas/genética , Animais , Linhagem Celular , Drosophila melanogaster , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo
20.
Mol Vis ; 18: 1093-106, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22701298

RESUMO

PURPOSE: To study susceptibility to glaucoma injury as it may be affected by mutations in ocular connective tissue components. METHODS: Mice homozygous for an N-ethyl-N-nitrosourea induced G257D exchange (Gly to Asp) missense mutation (Aca23) in their collagen 8A2 gene were studied to measure intraocular pressure (IOP), axial length and width, number of retinal ganglion cells (RGC), and inflation responses. Three month old homozygous Aca23 mutant and wild type (WT) mice had 6 weeks exposure to elevated IOP induced by polystyrene microbead injection. Additional Aca23 and matched controls were studied at ages of 10 and 18 months. RESULTS: Aca23 mice had no significant difference from WT in IOP level, and in both strains IOP rose with age. In multivariable models, axial length and width were significantly larger in Aca23 than WT, became larger with age, and were larger after exposure to glaucoma (n=227 mice). From inflation test data, the estimates of scleral stress resultants in Aca23 mice were similar to age-matched and younger WT C57BL/6 (B6) mice, while the strain estimates for Aca23 were significantly less than those for either WT group in the mid-sclera and in some of the more anterior scleral measures (p<0.001; n=29, 22, 20 eyes in Aca23, older WT, younger WT, respectively). With chronic IOP elevation, Aca23 eyes increased 9% in length and 7% in width, compared to untreated fellow eyes (p<0.05, <0.01). With similar elevated IOP exposure, WT eyes enlarged proportionately twice as much as Aca23, increasing in length by 18% and in nasal-temporal width by 13% (both p<0.001, Mann-Whitney test). In 4 month old control optic nerves, mean RGC axon number was not different in Aca23 and WT (46,905±7,592, 43,628±11,162, respectively; p=0.43, Mann-Whitney test, n=37 and 29). With chronic glaucoma, Aca23 mice had a mean axon loss of only 0.57±17%, while WT mice lost 21±31% (median loss: 1% versus 10%, n=37, 29, respectively; p=0.001; multivariable model adjusting for positive integral IOP exposure). CONCLUSIONS: The Aca23 mutation in collagen 8α2 is the first gene defect found to alter susceptibility to experimental glaucoma, reducing RGC loss possibly due to differences in mechanical behavior of the sclera. Detailed study of the specific changes in scleral connective tissue composition and responses to chronic IOP elevation in this strain could produce new therapeutic targets for RGC neuroprotection.


Assuntos
Colágeno Tipo VIII/genética , Glaucoma/genética , Hipertensão Ocular/genética , Células Ganglionares da Retina/patologia , Animais , Comprimento Axial do Olho/efeitos dos fármacos , Axônios/efeitos dos fármacos , Axônios/patologia , Contagem de Células , Modelos Animais de Doenças , Etilnitrosoureia , Glaucoma/induzido quimicamente , Glaucoma/patologia , Homozigoto , Pressão Intraocular/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Microesferas , Mutação de Sentido Incorreto , Hipertensão Ocular/induzido quimicamente , Hipertensão Ocular/patologia , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/patologia , Tamanho do Órgão , Poliestirenos , Isoformas de Proteínas/genética , Células Ganglionares da Retina/efeitos dos fármacos , Esclera/efeitos dos fármacos , Esclera/patologia
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