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1.
Int Ophthalmol ; 44(1): 137, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489070

RESUMO

PURPOSE: To evaluate the thickness of anterior sclera and corneal layers in patients with systemic sclerosis. METHODS: The present cross-sectional study included 41 patients with systemic sclerosis and 41 age- and gender-matched healthy controls. The study and control groups were compared in terms of the thickness of anterior sclera, corneal epithelium, Bowman's layer, corneal stroma, and Descemet's membrane-endothelium complex. The thickness measurements were obtained using the anterior segment module of spectral-domain optical coherence tomography. RESULTS: The thickness of anterior sclera, corneal epithelium, Bowman's layer, and Descemet's membrane-endothelium complex were similar in the patients with systemic sclerosis and healthy controls (P > 0.05). Total corneal thickness at the apex was 511.1 ± 33.5 µm in the systemic sclerosis group and 528.4 ± 29.5 µm in the control group (P = 0.015). The corneal stroma was thinner in the systemic sclerosis patients compared to the healthy controls (P = 0.02). CONCLUSIONS: The corneal stroma was thinner in the patients with systemic sclerosis compared to that of healthy controls, while the thickness of the anterior sclera was similar in both groups.


Assuntos
Epitélio Corneano , Esclera , Humanos , Estudos Transversais , Córnea , Substância Própria , Tomografia de Coerência Óptica/métodos
2.
J Chem Inf Model ; 63(15): 4839-4849, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37491825

RESUMO

Dihydrofolate reductase (DHFR) is an important drug target and a highly studied model protein for understanding enzyme dynamics. DHFR's crucial role in folate synthesis renders it an ideal candidate to understand protein function and protein evolution mechanisms. In this study, to understand how a newly proposed DHFR inhibitor, 4'-deoxy methyl trimethoprim (4'-DTMP), alters evolutionary trajectories, we studied interactions that lead to its superior performance over that of trimethoprim (TMP). To elucidate the inhibition mechanism of 4'-DTMP, we first confirmed, both computationally and experimentally, that the relative binding free energy cost for the mutation of TMP and 4'-DTMP is the same, pointing the origin of the characteristic differences to be kinetic rather than thermodynamic. We then employed an interaction-based analysis by focusing first on the active site and then on the whole enzyme. We confirmed that the polar modification in 4'-DTMP induces additional local interactions with the enzyme, particularly, the M20 loop. These changes are propagated to the whole enzyme as shifts in the hydrogen bond networks. To shed light on the allosteric interactions, we support our analysis with network-based community analysis and show that segmentation of the loop domain of inhibitor-bound DHFR must be avoided by a successful inhibitor.


Assuntos
Escherichia coli , Antagonistas do Ácido Fólico , Escherichia coli/metabolismo , Tetra-Hidrofolato Desidrogenase/química , Timidina Monofosfato , Antagonistas do Ácido Fólico/farmacologia , Antagonistas do Ácido Fólico/química , Trimetoprima/farmacologia , Trimetoprima/química , Trimetoprima/metabolismo
3.
J Chem Inf Model ; 62(24): 6715-6726, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-35984987

RESUMO

Antibiotic resistance is a global health problem in which mutations occurring in functional proteins render drugs ineffective. The working mechanisms of the arising mutants are seldom apparent; a methodology to decipher these mechanisms systematically would render devising therapies to control the arising mutational pathways possible. Here we utilize Cα-Cß bond vector relaxations obtained from moderate length MD trajectories to determine conduits for functionality of the resistance conferring mutants of Escherichia coli dihydrofolate reductase. We find that the whole enzyme is synchronized to the motions of the substrate, irrespective of the mutation introducing gain-of-function or loss-of function. The total coordination of the motions suggests changes in the hydrogen bond dynamics with respect to the wild type as a possible route to determine and classify the mode-of-action of individual mutants. As a result, nine trimethoprim-resistant point mutations arising frequently in evolution experiments are categorized. One group of mutants that display the largest occurrence (L28R, W30G) work directly by modifying the dihydrofolate binding region. Conversely, W30R works indirectly by the formation of the E139-R30 salt bridge which releases energy resulting from tight binding by distorting the binding cavity. A third group (D27E, F153S, I94L) arising as single, resistance invoking mutants in evolution experiment trajectories allosterically and dynamically affects a hydrogen bonding motif formed at residues 59-69-71 which in turn modifies the binding site dynamics. The final group (I5F, A26T, R98P) consists of those mutants that have properties most similar to the wild type; these only appear after one of the other mutants is fixed on the protein structure and therefore display clear epistasis. Thus, we show that the binding event is governed by the entire enzyme dynamics while the binding site residues play gating roles. The adjustments made in the total enzyme in response to point mutations are what make quantifying and pinpointing their effect a hard problem. Here, we show that hydrogen bond dynamics recorded on sub-µs time scales provide the necessary fingerprints to decipher the various mechanisms at play.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Tetra-Hidrofolato Desidrogenase , Escherichia coli/enzimologia , Ligação de Hidrogênio , Cinética , Mutação , Mutação Puntual , Tetra-Hidrofolato Desidrogenase/química , Proteínas de Escherichia coli/química
4.
Optom Vis Sci ; 98(3): 285-288, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33633023

RESUMO

SIGNIFICANCE: The mechanisms of sighting ocular dominance, which is particularly important in monovision therapies and sports vision, are not fully understood yet. Whether the macula affects ocular dominance or ocular dominance affects the macula is also a subject of interest. PURPOSE: The aim of this study was to investigate the relationship of sighting ocular dominance with macular photostress test time and middle macular layer thickness. METHODS: One-hundred eyes of 50 healthy adult volunteers were included in this cross-sectional study. Sighting eye dominance was decided by a hole-in-the-card test. The macular photostress test was performed by exposing the eye to the ophthalmoscope light for 10 seconds and measuring the time taken to return to visual acuity within one row of pre-light exposure acuity. The spectral-domain optical coherence tomography examinations were performed to measure thickness of middle macular layers (i.e., outer nuclear, outer plexiform, inner nuclear, and inner plexiform). Refractive error and intraocular pressure (IOP) measurements were also recorded. RESULTS: The comparison of dominant and nondominant eyes in the aspect of refractive error, IOP, and macular photostress test time did not show statistically significant differences (P > .05). The thicknesses of macular outer nuclear, outer plexiform, inner nuclear, and inner plexiform layers were similar in the dominant and nondominant eyes (P > .05). In addition, macular photostress time was not statistically significantly correlated with the thickness of middle macular layers (P > .05). CONCLUSIONS: The thickness of middle macular layers and macular photostress recovery time are similar in dominant and nondominant eyes.


Assuntos
Dominância Ocular/fisiologia , Macula Lutea/efeitos da radiação , Estimulação Luminosa , Adulto , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Macula Lutea/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Oftalmoscópios , Recuperação de Função Fisiológica/fisiologia , Erros de Refração , Fatores de Tempo , Tomografia de Coerência Óptica , Visão Monocular , Acuidade Visual/fisiologia , Adulto Jovem
5.
Int Ophthalmol ; 41(8): 2723-2728, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33818675

RESUMO

PURPOSE: To show alterations of retinal arteriolar caliber (RAC), retinal venular caliber (RVC), retinal nerve fiber layer thickness (RNFLT), peripapillary choroidal thickness (ppCT), and central macular thickness (CMT) in acute and chronic phases of nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: Forty-one eyes of 41 patients with NAION were included in this retrospective study. RAC, RVC, RNFLT, ppCT, and CMT measurements were performed via spectral-domain optical coherence tomography in the acute and chronic phases of NAION. RESULTS: RVC, RNFLT, ppCT, and CMT were significantly thinner in the chronic phase compared to the acute phase (p < 0.001), whereas RAC remained similar throughout the visits (p = 0.26). The visual acuity difference between the acute and chronic phases was not correlated with the changes of RAC, RVC, RNFLT, ppCT, or CMT. CONCLUSIONS: RVC, RNFLT, ppCT, and CMT decreases in the chronic phase when compared to the acute phase of NAION, whereas RAC does not change significantly.


Assuntos
Disco Óptico , Neuropatia Óptica Isquêmica , Humanos , Fibras Nervosas , Neuropatia Óptica Isquêmica/diagnóstico , Células Ganglionares da Retina , Estudos Retrospectivos , Tomografia de Coerência Óptica
6.
Graefes Arch Clin Exp Ophthalmol ; 258(1): 23-30, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31713751

RESUMO

PURPOSE: To investigate the association of retinal biomarkers with the choroidal parameters in retinitis pigmentosa (RP). METHODS: This prospective study included 69 eyes of 36 patients with RP. Choroidal vascularity index (CVI) was defined as the ratio of luminal area to stromal area after binarization on EDI-OCT images. Choroidal thickness (CT); peripapillary CT, the disruptions of the ellipsoid zone (EZ) and external limiting membrane (ELM); and the existence of disorganization of the retinal inner layers (DRIL) and epiretinal membrane (ERM) in central 1000 µm were noted. RESULTS: Having DRIL and the disruption of EZ and ELM was significantly associated with higher CVI (p < 0.001, p = 0.001, and p = 0.002 respectively) and lower peripapillary CT in temporal sector (p = 0.031, p = 0.012, and p = 0.043 respectively). Having ERM, the disruption of EZ and ELM was significantly associated with lower visual acuity (VA) (p = 0.044, p < 0.001, and p < 0.001 respectively). The eyes with ERM had significantly lower peripapillary retinal nerve fiber thickness (pRNFLT) (p = 0.040). The mean peripapillary CT significantly and positively correlated with the temporal, nasal, superonasal, and the mean pRNFLT (r = 0.258, p = 0.036, r = 0.252, p = 0.041, r = 0.260, p = 0.035, r = 0.280, p = 0.023 respectively). VA did not significantly correlate with CT, peripapillary CT, or CVI (p > 0.05). CONCLUSION: The disruption outer retinal segment integrity was significantly associated with higher CVI and lower peripapillary CT in temporal segment. ERM and disruption of ELM and EZ were associated with worse VA. VA did not significantly correlate with CT, peripapillary CT, or CVI.


Assuntos
Corioide/irrigação sanguínea , Angiofluoresceinografia/métodos , Vasos Retinianos/patologia , Retinose Pigmentar/diagnóstico , Tomografia de Coerência Óptica/métodos , Adulto , Corioide/diagnóstico por imagem , Feminino , Fundo de Olho , Humanos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Acuidade Visual
7.
J Anim Physiol Anim Nutr (Berl) ; 104(1): 136-143, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31544992

RESUMO

This study aimed to investigate the effect of l-carnitine and energy level and on oxidant/antioxidant balance in laying hens subjected to high stocking density. A total of 176, 32-week-old laying hens were assigned to eight groups with four replicates and hens in four groups were placed at the normal stocking densities of 500 cm2 /hen (four hens per cage) and in the remaining four groups were placed at the high stocking densities of 287.5 cm2 /hen (seven hens per cage). Hens received diets of high (2,850 kcal/kg ME) or normal (2,650 kcal/kg ME) energy which are supplemented with 0 or 200 mg/kg l-carnitine for 70 days. Results showed that exposure to high stocking density increased (p < .05) plasma malondialdehyde (MDA) and nitric oxide (NO) levels and decreased (p < .05) erythrocyte superoxide dismutase (SOD), catalase (CAT) and superoxide dismutase (GPx) activities. l-carnitine supplementation increased (p < .05) erythrocyte SOD, CAT and GPx activities, and decreased (p <.05) MDA and NO level in high stocking densities. The oxidan/antioxidan balance of birds was not influenced by increasing dietary energy level. The results of the present study indicate that the supplementation of l-carnitine to the birds subjected to high stocking density could effectively reverse the negative effects of high stocking density by improving oxidant/antioxidant balance. Therefore, l-carnitine supplementation at level of 200 mg/kg to diet may be as a favourable alternative to deal with oxidative stress caused by high stocking density in laying hens.


Assuntos
Antioxidantes/metabolismo , Carnitina/farmacologia , Galinhas/fisiologia , Suplementos Nutricionais , Malondialdeído/sangue , Óxido Nítrico/sangue , Criação de Animais Domésticos , Animais , Eritrócitos/enzimologia , Abrigo para Animais , Oviposição , Oxidantes/sangue , Estresse Fisiológico
8.
Exp Physiol ; 104(4): 505-513, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30677174

RESUMO

NEW FINDINGS: What is the central question of this study? The study was designed to assess whether pretreatment with ß-glucan could exert any protective action against isoprenaline-induced myocardial injury in rats. What is the main finding and its importance? ß-Glucan pretreatment could reduce myocardial injury by restoring cardiac biomarkers, antioxidant status, apoptosis and histopathological changes. Therefore, ß-glucan might have the potential to be used in the prevention and/or treatment of myocardial infarction. ABSTRACT: This study was designed to investigate the cardioprotective effect of pretreatment with ß-glucan, the glucose polymer derived from the yeast Saccharomyces cerevisiae, against isoprenaline (ISO)-induced myocardial injury in rats by studying biochemical cardiac markers, antioxidant parameters, apoptosis, ECG and histopathological changes. Male Sprague-Dawley rats were randomly divided into four treatment groups, namely control, ß-glucan, isoprenaline and ß-glucan + isoprenaline. The ß-glucan treatment group received ß-glucan (50 mg kg-1  day-1 , p.o.) for 10 days. Myocardial injury was induced by ISO administration (100 mg kg-1 , s.c.) twice, at an interval of 24 h, on the 9th and 10th days. Isoprenaline administration resulted in a marked increase in heart rate, ST segment elevation, myocardial malondialdehyde content, cardiac marker levels (lactate dehydrogenase, creatine kinase-MB and high-sensitivity cardiac troponin T) and apoptotic index, and a significant decrease in R-wave amplitude and myocardial superoxide dismutase, catalase and glutathione peroxidase activities. In addition, apoptosis, congestion, necrosis, inflammatory cell infiltration and myofibrillar disorganization were observed histologically in myocardial tissue sections. The oral pretreatment with ß-glucan prevented almost all the parameters of isoprenaline-induced myocardial injury in rats, and these findings were confirmed by the histopathological analysis. These findings provide evidence that ß-glucan could protect rat myocardium against ISO-induced myocardial injury, and this was attributed to its antioxidant and anti-apoptotic properties.


Assuntos
Coração/efeitos dos fármacos , Isoproterenol/farmacologia , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , beta-Glucanas/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Cardiotônicos/farmacologia , Catalase/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
9.
Can J Physiol Pharmacol ; 97(5): 407-412, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30726105

RESUMO

This study was conducted to investigate the possible protective effects of ghrelin against tilmicosin-induced acute ventricular dysfunction in rats. Forty adult male Sprague Dawley rats were randomly divided into 4 equal groups: control, ghrelin, tilmicosin, and ghrelin + tilmicosin. The left ventricular structural and functional parameters together with cardiac biomarker levels were evaluated. The results showed that tilmicosin treatment alone significantly decreased the left ventricular fractional shortening, left ventricular ejection fraction, left ventricular stroke volume, and cardiac output when compared with control group. In addition, tilmicosin led to a significant increase in left ventricular internal dimension in systole and left ventricular fractional end-systolic volume. At the same time, serum lactate dehydrogenase, creatine kinase, and creatine kinase-myocardial B fraction levels were significantly increased in tilmicosin-treated group when compared with control group. However, ghrelin pretreatment significantly prevented the left ventricular internal dimension in systole, left ventricular fractional end-systolic volume, left ventricular stroke volume, left ventricular ejection fraction, left ventricular fractional shortening, and cardiac output changes caused by tilmicosin. Moreover, ghrelin pretreatment could reduce significantly serum lactate dehydrogenase, creatine kinase, and creatine kinase-myocardial B fraction levels. These data indicated that ghrelin treatment may provide a protective effect against tilmicosin-induced left ventricular systolic dysfunction.


Assuntos
Grelina/farmacologia , Tilosina/análogos & derivados , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Creatina Quinase/sangue , L-Lactato Desidrogenase/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Tilosina/efeitos adversos , Disfunção Ventricular Esquerda/sangue
10.
Retina ; 39(7): 1416-1423, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29528981

RESUMO

PURPOSE: To evaluate choroidal, macular, peripapillary retinal nerve fiber layer (RNFL) thicknesses and retinal vascular caliber alterations in HIV-1-infected patients without opportunistic infections. METHODS: This cross-sectional study included 45 HIV-1-infected patients and 47 healthy subjects. Spectral domain optical coherence tomography was used for assessment of choroidal, macular, peripapillary RNFL thicknesses and retinal vascular caliber alterations. RESULTS: The mean CD4 count was 426 ± 226 cells per milliliter and the mean HIV-1 RNA level was 1.8 × 10 ± 3.6 × 10 copies/mL in HIV-infected group. Central inner plexiform, superior photoreceptor, superior and nasal retinal pigment epithelium layers were thinner in HIV-infected patients compared with control subjects (P < 0.05). The differences in sectoral retinal thicknesses lost their significance after Bonferroni correction (P < 0.01). The average thickness of pericentral retina within 3 mm was thinner in the photoreceptor layer in HIV-infected patients compared with control subjects (P = 0.033). The differences in peripapillary RNFL thickness, choroidal thickness, and retinal vascular caliber were not significant between the groups. Choroidal thickness and pericentral outer plexiform were thinner, whereas peripapillary RNFL was thicker in newly diagnosed cases (16 patients) compared with patients having treatment for at least 4 months or longer (27 patients, P < 0.05, Mann-Whitney U test). HIV-1 RNA showed negative correlation with choroidal thickness (r = -0.435, P = 0.003) and positive correlation with peripapillary RNFL in central (r = 0.323, P = 0.032) and superonasal (r = 0.369, P = 0.014) sectors. CONCLUSION: Choroidal thickness was thinner in newly diagnosed patients compared with patients on treatment. Viral load showed negative correlation with choroidal thickness. Retinal segmental alterations occurred in HIV-infected patients compared with control subjects.


Assuntos
Corioide/patologia , Infecções Oculares Virais/diagnóstico , Infecções por HIV/diagnóstico , HIV-1 , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Prognóstico , Retinite , Acuidade Visual , Adulto Jovem
11.
Int Ophthalmol ; 39(9): 2049-2056, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30421317

RESUMO

PURPOSE: To assess the change in the macular layers in the fellow eyes of unilateral retinal vein occlusion (RVO) patients and to evaluate whether certain layers are more affected based on RVO type. METHODS: This retrospective study included 87 fellow eyes of patients with unilateral RVO (26 central, 61 branch) and 105 eyes of 105 subjects without RVO. Spectral domain optical coherence tomography was used for automatized retinal segmentation. The thicknesses of retinal nerve fiber layer (RNFL), ganglion cells, inner plexiform, inner nuclear, outer plexiform, outer nuclear, photoreceptor layers, overall inner retinal layers and retinal pigment epithelium (RPE) were documented. RESULTS: Inner plexiform layer was thinner in inferior sector in RVO group compared with the control group (p = 0.047). The subgroup analysis showed that the retina was thinner in RVO group compared with the controls without systemic diseases in some sectors of the following layers: inferior retina, RNFL, ganglion cell layer, inner plexiform layer, inner retinal layers and RPE (p < 0.05). Retinal thickness was decreased in the fellow eyes of branch RVO group compared to that in the central RVO group in the some sectors (p < 0.05). CONCLUSIONS: The fellow eyes of unilateral RVO patients did not show major structural differences compared with the controls; however, they revealed significant sectoral thinning in many retinal layers when compared with the eyes of healthy subjects without systemic diseases. Central macula was thinner in the fellow eyes of patients with branch RVO compared to that in central RVO.


Assuntos
Macula Lutea/patologia , Células Ganglionares da Retina/patologia , Epitélio Pigmentado da Retina/patologia , Oclusão da Veia Retiniana/diagnóstico , Tomografia de Coerência Óptica/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Estudos Retrospectivos
12.
Graefes Arch Clin Exp Ophthalmol ; 256(10): 1801-1806, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29922890

RESUMO

BACKGROUND: Macular contraction after anti-vascular endothelial growth factor (anti-VEGF) injections for diabetic macular edema (DME) was evaluated by documenting the displacement of macular capillary vessels and epiretinal membrane (ERM) formation. METHODS: A total of 130 eyes were included in this retrospective study. The study group consisted of 63 eyes which had intravitreal anti-VEGF injections for DME, and the control group included 67 eyes without central DME. The study and the control groups were well balanced in terms of diabetes duration and HbA1c. The distances between the bifurcation of the macular capillary retinal vessels were measured, and ERM status was evaluated based on spectral-OCT findings on the initial and final visit. RESULTS: In the study group, the mean number of injections was 4.7 ± 2.6 (3-14). The mean follow-up time was 16.7 ± 7.8 months in the study group whereas it was 20.7 ± 10.9 months in the control group (p = 0.132). The change in distance measurements between the reference points on macular capillary vessels was significant in all lines except line c (p < 0.05 for lines a, b, d, e, and f) in the study group whereas it was significant in only line e in the control group (p = 0.007, paired samples test). However, when the change in macular thickness was accounted as a confounding factor, the change in distances between the references points from the initial visit to the final visit lost its significance (repeated measures ANCOVA, p > 0.05). During follow-up, the number of cases with ERM changed from 10 to 12 in the study group whereas it remained three in the control group. CONCLUSION: There was a displacement of macular capillary vessels which was associated with the change in macular thickness in eyes having anti-VEGF injections for DME. The number of ERM cases did not change significantly during the follow-up.


Assuntos
Bevacizumab/administração & dosagem , Retinopatia Diabética/tratamento farmacológico , Macula Lutea/patologia , Edema Macular/diagnóstico , Ranibizumab/administração & dosagem , Acuidade Visual , Corpo Vítreo/patologia , Inibidores da Angiogênese/administração & dosagem , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/patologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
13.
Eye Contact Lens ; 44 Suppl 2: S281-S284, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29438122

RESUMO

OBJECTIVES: To evaluate corneal and anterior chamber morphology as measured by Pentacam HR in human immunodeficiency virus (HIV)-infected patients without opportunistic infections and to search for signs of accelerated aging. METHODS: This prospective study included 41 eyes of 41 HIV-1-infected patients (study group) and 50 eyes of 50 healthy subjects (control group). Specular microscope and Pentacam HR were used for corneal and anterior chamber morphology evaluation. Corneal endothelial cell density (CECD), hexagonal cell ratio, coefficient of variation, corneal thickness, density and volume, maximum keratometry, anterior chamber volume (ACV), and anterior chamber depth (ACD) measurements were recorded for analysis. RESULTS: The mean CD4 count was 428.3±231.9 (36-950) cells/mL, and the time since diagnosis was 27.5±34.1 months in the study group. The difference in anterior segment parameters was not significantly different between the study and the control groups (P>0.05). Age significantly correlated with CECD (r=-0.436, P=0.004), ACV (r=-0.570, P<0.001), ACD (r=-0.471, P=0.002), and corneal density (r=0.424, P=0.006) in the study group, whereas it did not show a significant correlation with any ocular parameters in the control group (Pearson correlation). CONCLUSION: Corneal density, CECD, ACV, and ACD showed significant correlation with age in HIV-1-infected patients. Further studies are needed to show whether ocular parameters may serve as useful tools to monitor HIV-related accelerated aging.


Assuntos
Câmara Anterior/patologia , Córnea/patologia , Infecções por HIV/patologia , HIV-1 , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , Contagem de Células , Células Endoteliais/citologia , Feminino , Infecções por HIV/virologia , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Fotografação , Estudos Prospectivos , Adulto Jovem
14.
BMC Ophthalmol ; 16: 1, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26728474

RESUMO

BACKGROUND: To evaluate the ocular pulse amplitude (OPA), the posterior pole asymmetry analysis (PPAA), the peripapillary retinal nerve fiber layer (RNFL) thickness, the ganglion cell layer (GCL) thickness, macular thickness and visual field testing in migraine patients without aura. METHODS: In this prospective, cross-sectional and comparative study 38 migraine patients and 44 age and sex matched controls were included. OPA was measured by dynamic contour tonometry (DCT), PPAA, RNFL, GCL and macular thickness were measured by Heidelberg Spectral Domain Optical Coherence Tomography (SD-OCT) and standard perimetry was performed using the Humphrey automated field analyzer. RESULTS: The difference in OPA was not statistically significant between the two groups (p ≥ 0.05). In the PPAA there was no significant difference between two hemispheres in each eye (p ≥ 0.05). The RNFL thickness was significantly reduced in the temporal and nasal superior sectors in the migraine group (p ≤ 0.05). The GCL and macular thickness measurements were thinner in migraine patients but the difference between groups was not statistically significant (p ≥ 0.05). There was no correlation between RNFL, GCL, macular thickness measurements and OPA values. There was no significant difference in the mean deviation (MD) and pattern standard deviation (PSD) between the two groups (p ≥ 0.05). CONCLUSIONS: Migraine patients without aura have normal OPA values, no significant asymmetry of the posterior pole and decreased peripapillary RNFL thickness in the temporal and nasal superior sectors compared with controls. These findings suggest that there is sectorial RNFL thinning in migraine patients without aura and pulsative choroidal blood flow may not be affected during the chronic course of disease.


Assuntos
Pressão Sanguínea/fisiologia , Pressão Intraocular/fisiologia , Enxaqueca com Aura/fisiopatologia , Fibras Nervosas/patologia , Células Ganglionares da Retina/patologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos , Tomografia de Coerência Óptica , Tonometria Ocular , Testes de Campo Visual , Campos Visuais/fisiologia , Adulto Jovem
15.
Optom Vis Sci ; 92(5): 573-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25875687

RESUMO

PURPOSE: Our aim was to evaluate the ultrasound (US) elastography of ocular and periocular structures in high myopia. METHODS: There were 20 eyes of 20 high myopic patients in the study group, whereas there were 20 eyes of 20 age- and sex-matched healthy participants in the control group. The eyes in the study group had myopia greater than -5.0 diopters and had axial length (AL) greater than 25.0 mm. The US elastography measurements were performed with the LOGIQ E9 Ultrasound Elastography. The elastography values of anterior vitreous, posterior vitreous (PV), retina-choroid-sclera complex (RCS), and retrobulbar fat tissue (RF) were measured in each eye. RESULTS: Anterior vitreous US elastography values were similar in both groups (p = 0.17), whereas PV is more elastic in high myopic eyes (p = 0.01). There was a moderate negative correlation between AL and RCS/RF elastography ratio (r = -0.35, p = 0.03) and a positive correlation between refractive error and RCS/RF elastography ratio (r = 0.36, p = 0.02). CONCLUSIONS: High myopia is associated with more elastic PV. Elasticity of posterior RCS increases as the AL increases.


Assuntos
Corioide/fisiologia , Elasticidade/fisiologia , Miopia Degenerativa/fisiopatologia , Retina/fisiologia , Esclera/fisiologia , Corpo Vítreo/fisiologia , Adulto , Comprimento Axial do Olho , Estudos Transversais , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Ophthalmologica ; 234(1): 55-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26138561

RESUMO

PURPOSE: To compare subfoveal choroidal thickness (SFCT), retinal vessel caliber, and ocular pulse amplitude between treated polycythemia vera (PV) patients and healthy adults. METHODS: Forty patients with PV and 40 age- and sex-matched healthy controls were recruited for this cross-sectional study. Spectral-domain optical coherence tomography was used for SFCT and retinal vessel caliber measurements. The Pascal dynamic contour tonometer was used for ocular pulse amplitude measurements. The correlations of blood hematocrit levels with the studied ocular parameters were analyzed. RESULTS: There were no statistically significant differences between the PV patients and controls in SFCT, retinal vessel caliber, and ocular pulse amplitude (p > 0.05). SFCT was associated with hematocrit level in both PV patients and healthy adults (p < 0.05). CONCLUSIONS: Although SFCT, retinal vessel caliber, and ocular pulse amplitude parameters are similar in treated PV patients and healthy controls, SFCT is associated with hematocrit level.


Assuntos
Corioide/patologia , Policitemia/sangue , Tomografia de Coerência Óptica/métodos , Adulto , Estudos Transversais , Feminino , Hematócrito , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Policitemia/diagnóstico , Prognóstico , Vasos Retinianos/patologia
17.
Clin Exp Ophthalmol ; 43(1): 47-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24995509

RESUMO

BACKGROUND: To investigate the association between age-related macular degeneration (AMD) and the polymorphisms of HIF1A, a major vascular epithelial growth factor regulator under hypoxic conditions. The associations of AMD and polymorphisms of genes CFH, SKIV2L and MYRIP were also studied. DESIGN: Prospective study. PARTICIPANTS: Eighty-seven AMD patients and 80 healthy subjects admitted to the Department of Ophthalmology at Pamukkale University Hospital, Denizli, Turkey, were included: 45 (52%) had wet type AMD, and 42 (48%) had dry type AMD. METHODS: Polymorphisms rs1061170 (CFH), rs429608 (SKIV2L), rs2679798 (MYRIP) and both rs11549465 and rs11549467 (HIF1A) were investigated in DNA isolated from peripheral blood samples of the cases and controls by dye-termination DNA sequencing. MAIN OUTCOME MEASURES: Genotype distribution of rs1061170 (CFH), rs429608 (SKIV2L), rs2679798 (MYRIP) and both rs11549465 and rs11549467 (HIF1A) in AMD cases and healthy controls; association between genotypes and AMD subtypes. RESULTS: Given the significant difference between the mean age of case and control groups (72.13 ± 5.77 vs. 62.80 ± 5.22, respectively) (P = .000), subsequent analyses were adjusted for age. We found that having at least one C allele for polymorphism rs1061170 increases AMD risk independent of age (OR = 2.42, 95% confidence interval [CI], 1.22-4.81). The ancestral T allele for polymorphism rs1061170 has a protective effect for AMD (OR = 0.53, 95% CI, 0.34-0.83). No statistically significant difference for distributions of other single nucleotide polymorphisms (SNPs) emerged between patients and healthy subjects. CONCLUSIONS: No associations appeared between HIF1A SNPs and AMD, which were studied here for the first time; however, polymorphism rs1061170 of the CFH gene is associated with AMD in our population.


Assuntos
Atrofia Geográfica/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Polimorfismo de Nucleotídeo Único , Fator A de Crescimento do Endotélio Vascular/metabolismo , Degeneração Macular Exsudativa/genética , Idoso , Fator H do Complemento/genética , DNA Helicases/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Análise de Sequência de DNA , Proteínas de Transporte Vesicular/genética
18.
Undersea Hyperb Med ; 42(1): 65-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26094306

RESUMO

BACKGROUND/AIMS: The aim of this study is to investigate the effect of head-out hot-water immersion on the intraocular pressure (IOP) of healthy subjects and investigate whether this intervention alters cardiovascular and microcirculatory responses. METHODs: 16 male and 18 female healthy young adults were immersed in 39 degrees C water up to shoulder level for 20 minutes. Blood pressure (BP), heart rate (HR) and IOP were measured pre-immersion, post-immersion and five minutes after immersion on the same day. Tono-Pen was used to measure IOP. Mean arterial blood pressure (MAP), systolic pressure rate product (S-PRP), diastolic pressure rate product (D-PRP), pulse pressure (PP), mean ocular perfusion pressure (mean-OPP), systolic ocular perfusion pressure (S-OPP) and diastolic ocular perfusion pressure (D-OPP) were calculated. RESULTS: Systolic BP (SBP), diastolic BP (DBP), MAP, IOP, S-OPP, D-OPP and mean-OPP decreased; HR increased five minutes after immersion in the pool and post-immersion out of the pool significantly, compared to pre-immersion data (p < 0.05). HR, S-PRP and D-PRP measured five minutes after immersion were significantly higher from post-immersion (p < 0.05). PP and S-OPP were significantly different five minutes after immersion compared to pre-immersion. There was no statistically significant correlation between IOP and SBP, DBP, MAP, S-PRP, D-PRP, PP, S-OPP, D-OPP, or mean-OPP (p > 0.05). CONCLUSIONS: Physiological hemodynamic response to single head-out hot-water immersion caused a statistically significant decrease in IOP. Preliminary results could help to clarify vascular reactions and IOP changes during hot-water immersion that might be potentially therapeutic in glaucoma patients.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Temperatura Alta , Imersão/fisiopatologia , Pressão Intraocular/fisiologia , Artérias/fisiologia , Feminino , Cabeça , Voluntários Saudáveis , Humanos , Masculino , Microcirculação/fisiologia , Fatores Sexuais , Fatores de Tempo , Tonometria Ocular , Adulto Jovem
19.
Cutan Ocul Toxicol ; 34(1): 42-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24754406

RESUMO

OBJECTIVE: To investigate the effects of intracameral carbachol in phacoemulsification surgery on central macular thickness (CMT), total macular volume (TMV) and retinal vessel caliber (RVC). MATERIALS AND METHODS: In this prospective consecutive case series, 82 patients underwent uneventful phacoemulsification and in-the-bag intraocular lens implantation. Unlike patients in the control group (43 eyes), patients in the study group (42 eyes) were injected with intracameral 0.01% carbachol during surgery. Spectral-domain optical coherence tomography (OCT) was used to analyze the parameters of CMT, TMV and RVC. RESULTS: On the first postoperative day, mean CMT and TMV decreased markedly in the carbachol group, though these values did not change significantly in the control group. During follow-up visits, no statistically significant differences between the groups occurred regarding changes in mean CMT (p = 0.25, first day; p = 0.80, first week; p = 0.95, first month). However, change in mean TMV between groups on the first postoperative day was statistically significant (p = 0.01, first day; p = 0.96, first week; p = 0.68, first month). RVC values were similar on the preoperative and postoperative first days in both groups (p > 0.05). DISCUSSION: Results suggest that the effect of intracameral carbachol on macular OCT is related to pharmacological effects, as well as optic events (e.g. miosis). CONCLUSION: Intracameral carbachol given during cataract surgery decreases macular thickness and volume in the early postoperative period but does not exert any gross effect on RVC.


Assuntos
Carbacol/efeitos adversos , Macula Lutea/efeitos dos fármacos , Mióticos/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carbacol/uso terapêutico , Feminino , Humanos , Implante de Lente Intraocular , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Mióticos/uso terapêutico , Facoemulsificação , Artéria Retiniana/efeitos dos fármacos , Veia Retiniana/efeitos dos fármacos , Tomografia de Coerência Óptica
20.
Int Ophthalmol ; 35(5): 657-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25186317

RESUMO

The purpose of the present study was to examine the effects of intravitreal ranibizumab on ocular pulse amplitude (OPA) and retinal vessel caliber (RVC) in wet age-related macular degeneration (AMD). Thirty-two eyes of 32 wet AMD patients were included in this case series. Three consecutive monthly injections of ranibizumab were performed. The OPA was measured with the Pascal dynamic contour tonometer. RVC measurements were taken with spectral-domain optical coherence tomography. Pre-injection mean OPA value was 2.55 ± 0.76 mmHg and post-injections mean OPA value was 2.79 ± 0.88 mmHg at the last visit (p = 0.10). Pre-injection mean arteriole and venule RVC were 96.7 ± 9.4 and 125.9 ± 8.4 µm; while post-injections arteriole and venule RVC were 96.0 ± 8.7 and 125.6 ± 8.9 µm, respectively (p > 0.05). OPA and RVC are unchanged after triple intravitreal ranibizumab injections, indicating that this treatment does not significantly alter gross retina-choroidal vasculature and hemodynamics.


Assuntos
Ranibizumab/uso terapêutico , Vasos Retinianos/efeitos dos fármacos , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Feminino , Angiofluoresceinografia , Humanos , Pressão Intraocular/fisiologia , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Pulso Arterial , Fluxo Sanguíneo Regional/fisiologia , Vasos Retinianos/patologia , Vasos Retinianos/fisiopatologia , Tomografia de Coerência Óptica , Tonometria Ocular , Degeneração Macular Exsudativa/fisiopatologia
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