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1.
Exp Eye Res ; 212: 108790, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34648773

RESUMO

Age related nuclear (ARN) cataracts in humans take years to form and so experimental models have been developed to mimic the process in animals as a means of better understanding the etiology of nuclear cataracts in humans. A major limitation with these animal models is that many of the biochemical and physiological changes are not typical of that seen in human ARN cataract. In this review, we highlight the work of Frank Giblin and colleagues who established an in vivo animal model that replicates many of the changes observed in human ARN cataract. This model involves exposing aged guinea pigs to hyperbaric oxygen (HBO), which by causing the depletion of the antioxidant glutathione (GSH) specifically in the lens nucleus, produces oxidative changes to nuclear proteins, nuclear light scattering and a myopic shift in lens power that mimics the change that often precedes cataract development in humans. However, this model involves multiple HBO treatments per week, with sometimes up to a total of 100 treatments, spanning up to eight months, which is both costly and time consuming. To address these issues, Giblin developed an in vitro model that used rabbit lenses exposed to HBO for several hours which was subsequently shown to replicate many of the changes observed in human ARN cataract. These experiments suggest that HBO treatment of in vitro animal lenses may serve as a more economical and efficient model to study the development of cataract. Inspired by these experiments, we investigated whether exposure of young bovine lenses to HBO for 15 h could also serve as a suitable acute model of ARN cataract. We found that while this model is able to exhibit some of the biochemical and physiological changes associated with ARN cataract, the decrease in lens power we observed was more characteristic of the hyperopic shift in refraction associated with ageing. Future work will investigate whether HBO treatment to age the bovine lens in combination with an oxidative stressor such as UV light will induce refractive changes more closely associated with human ARN cataract. This will be important as developing an animal model that replicates the changes to lens biochemistry, physiology and optics observed in human ARN cataracts is urgently required to facilitate the identification and testing of anti-cataract therapies that are effective in humans.


Assuntos
Envelhecimento , Catarata/metabolismo , Oxigenoterapia Hiperbárica/métodos , Cristalino/química , Óptica e Fotônica , Animais , Catarata/fisiopatologia , Bovinos , Humanos , Cristalino/diagnóstico por imagem , Cristalino/fisiologia , Microscopia com Lâmpada de Fenda
2.
Acta Myol ; 39(2): 90-93, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32904905

RESUMO

Myotonic dystrophy (DM1) is the most common muscle disease in adults, affecting approximately 1:8000 individuals, characterized by myotonia and muscular wasting and a multisystemic involvement that includes heart, brain, respiratory and endocrine system, and eye. Conduction system is selectively involved, often causing cardiac sudden death. Early onset posterior subcapsular cataract is a characteristic feature of myotonic dystrophy, requiring surgical treatment. However, DM1 is associated with many anesthetic hazards; sensitivity to anesthetic drugs, especially muscle relaxants and opioids, may complicate postoperative care. Local anesthesia also requires attention. We investigated the heart response to local anesthesia Ropivacaine Hcl administration in 16 DM1 patients (12M:4F) consecutively undergoing cataract surgery, by analyzing heart rate, ventricular and supraventricular ectopic beats, runs of tachycardia and pauses ≥ 2.5 sec., through a 24h-Holter monitoring, registered before and within 24 hours after surgery. The average age of patients was 47.4 years (range 30.2-55.9). At baseline, one patient had a pacemaker and 3 a defibrillator. Two patients presented a first-degree atrio-ventricular-block; three showed ectopic ventricular beats, on anti-arrhythmic drug treatment. No significant differences in heart rate values (73 ± 15b/m versus 76 ± 13b/m) were observed after cataract surgery, nor in the onset of ectopic beats. Only patients who presented ventricular ectopic beats at baseline, showed an increase in their number after surgery, likely related to an arbitrary interruption of the specific treatment. These data confirm the safety and efficacy of ropivacaine HCl used as a local anesthetic in patients with myotonic dystrophy.


Assuntos
Anestesia Local , Anestésicos Locais/uso terapêutico , Extração de Catarata , Catarata/complicações , Distrofia Miotônica/complicações , Ropivacaina/uso terapêutico , Adulto , Catarata/fisiopatologia , Estudos de Coortes , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/fisiopatologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-31730524

RESUMO

Magnesium (Mg2+) is one of the major elements required to maintain normal metabolism and ionic balances in ocular tissues. The physiological role of Mg2+ is mediated through maintaining the Na+-K+-ATPase on membrane, favoring energy-generating reactions, replication of DNA and protein synthesis. Despite the wide availability of this element, hypomagnesemia has been associated with many human ailments. Recent studies highlighted the association of hypomagnesemia and, thereby, supplementation of Mg2+ in the management of eye diseases. Glaucoma, senile cataract and diabetic retinopathy were associated with low level of extracellular Mg2+. The neurovascular protective effects of Mg2+ mediated through activation of endothelial nitric oxide synthase and inhibition of endothelin-1 eventually result in vasodilatation of retinal vessels. Mg2+ can maintain the lens sodium pump activity and antioxidant status and block the calcium channels and release of glutamate in nerve endings. Furthermore, it can prevent the apoptosis of retinal ganglion cells. All these effects contribute to its being a pharmacological agent against ocular diseases. However, clinical trials are scant. This article discusses the role of Mg2+ as a possible therapeutic agent in the management of glaucoma, cataract and diabetic retinopathy.


Assuntos
Catarata/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Glaucoma/tratamento farmacológico , Magnésio/administração & dosagem , Animais , Antioxidantes/metabolismo , Catarata/fisiopatologia , Retinopatia Diabética/fisiopatologia , Glaucoma/fisiopatologia , Humanos , Magnésio/sangue , ATPase Trocadora de Sódio-Potássio/metabolismo
4.
Acta Ophthalmol ; 97(6): 596-602, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30690920

RESUMO

PURPOSE: To examine visual acuity, refraction and ocular status before, during and after hyperbaric oxygen therapy (HBOT). METHODS: Twenty-nine patients underwent 40 standard protocol HBOT treatments. In all subjects, refraction and best corrected visual acuity were measured at baseline and after ten, 20, 30 and 40 treatments, and at a 12-week follow-up. A subgroup (n = 19) were given additional examinations at baseline, after 40 treatments and at follow-up including measuring central corneal thickness (CCT), corneal curvature, anterior chamber depth, lens thickness, axial length, fundus morphology, blood pressure and intraocular pressure (IOP). Lens colour and opalescence were graded using the Lens Opacities Classification System III (LOCS III). RESULTS: Myopic shifts [≥0.5 dioptre (D) spherical equivalent (SE)] occurred in 45 (77.6%) eyes. Median refractive changes of -0.75 D SE (right eye; p < 0.001) and -0.66 D SE (left eye; p < 0.001) were observed between pretreatment and treatment end (Wilcoxon signed rank test). Refraction returned to baseline at follow-up, except for a small persisting change towards myopia, median -0.25 D SE (left eye; p = 0.01). Using the LOCS III, median increases in lens nuclear colour, of 0.6 (right eye; p < 0.001) and 0.7 (left eye; p < 0.001), and opalescence of 0.7 (both eyes; p = 0.01) were found at the last examination. Small reductions were noted in CCT of -6.00 µm (right eye; p = 0.03) and -4.00 µm (left eye; p = 0.03), and IOP of -1.50 mmHg (left eye; p = 0.01). CONCLUSIONS: The transient myopic shift may have been due to lenticular refractive index changes. Reduced lens transparency is a potential consequence of HBOT.


Assuntos
Catarata/prevenção & controle , Oxigenoterapia Hiperbárica/métodos , Cristalino/fisiopatologia , Miopia/terapia , Refração Ocular/fisiologia , Acuidade Visual , Adolescente , Adulto , Idoso , Catarata/etiologia , Catarata/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/complicações , Miopia/fisiopatologia , Prognóstico , Estudos Prospectivos , Adulto Jovem
5.
PLoS One ; 13(2): e0192774, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29432447

RESUMO

A more holistic understanding of the benefits of sight-restoring cataract surgery requires a focus that goes beyond income and employment, to include a wider array of well-being measures. The objective of this study is to examine the monetary and non-monetary benefits of cataract surgery on both patients as well as their caregivers in Vietnam. Participants were randomly recruited from a Ho-Chi-Minh City Hospital. A total of 82 cataract patients and 83 caregivers participated in the survey conducted for this study. Paired t-tests, Wilcoxon Signed Rank tests, and regression analysis are used to detect any statistically significant differences in various measures of well-being for patients and caregivers before and after surgery. There are statistically significant improvements in monetary and non-monetary measures of well-being for both patients and caregivers approximately three months after undergoing cataract surgery, compared with baseline assessments collected prior to surgery. Non-monetary measures of well-being include self-assessments of overall health, mental health, hope, self-efficacy, happiness and life satisfaction. For patients, the benefits included statistically significant improvements in earnings, mobility, self-care, the ability to undertake daily activities, self-assessed health and mental health, life satisfaction, hope, and self-efficacy (p<0.01). For caregivers, attendance at work improved alongside overall health, mental health, hope, self-efficacy, happiness and life satisfaction, three months post-surgery (p<0.01). Restoring sight has positive impacts for those suffering from cataracts and their caregivers. Sometimes the benefits are almost equal in their magnitude. The study has also demonstrated that many of these impacts are non-monetary in nature. It is clear that estimates of the rate of return to restoring sight that focus only on financial gains will underestimate the true returns to society of restoring sight from cataract surgeries.


Assuntos
Extração de Catarata , Catarata/fisiopatologia , Visão Ocular , Idoso , Cuidadores/psicologia , Feminino , Nível de Saúde , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Satisfação do Paciente , Autoeficácia , Vietnã
6.
Chem Biodivers ; 12(12): 1881-90, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26663841

RESUMO

Luteolin, a flavonoid present in leaves and stems of many plants finds mention in literature for beneficial effects on eyes. Presently, no reports are available on the in vivo anticataractogenic effect of luteolin. The current study was designed to evaluate the efficacy of luteolin on selenite-induced cataract models in vivo. The study consisted of three groups of Sprague Dawley rat pups 8-10 d old (Group I (Normal), Group II (Cataract induced), and Group III (Treatment)). Cataract was induced in Group II and Group III by a subcutaneous injection of sodium selenite (4 µg/g body weight) on the 10th day. Luteolin was administered orally from 8th day up to 12th day at a concentration of 1 µg/g body weight in Group III. After 30 d, lenses of treated animals showed normal morphology. Activities of antioxidant enzymes were increased and levels of reactive oxygen species were decreased in the luteolin-treated group when compared to the cataract-induced group. Increased Ca(2+) ATPase activity and lowered calcium level, caspase 3 activity and down-regulation of caspase 3 expression were seen in the treatment group when compared to the selenite group. Luteolin enhances the antioxidant potential and thereby lowers the oxidative damages to the lens. It also stabilizes the membrane integrity of the lens and maintains the ionic balance.


Assuntos
Catarata/prevenção & controle , Suplementos Nutricionais , Luteolina , Ácido Selenioso , Animais , Caspase 3/genética , Catarata/induzido quimicamente , Catarata/fisiopatologia , Regulação da Expressão Gênica , Luteolina/administração & dosagem , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/química
7.
Hum Brain Mapp ; 36(12): 5265-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26417668

RESUMO

Individuals who are born blind due to dense bilateral cataracts and who later regain vision due to cataract surgery provide a unique model to evaluate the effect of early sensory experience in humans. In recent years, several studies have started to assess the functional consequences of early visual deprivation in these individuals, revealing a number of behavioral impairments in visual and multisensory functions. In contrast, the extent to which a transient period of congenital visual deprivation impacts brain structure has not yet been investigated. The present study investigated this by assessing cortical thickness of occipital areas in a group of six cataract-reversal individuals and a group of six age-matched normally sighted controls. This analysis revealed higher cortical thickness in cataract-reversal individuals in the left calcarine sulcus, in the superior occipital gyrus and in the transverse occipital sulcus bilaterally. In addition, occipital cortical thickness correlated negatively with behavioral performance in an audio-visual task for which visual input was critical, and positively with behavioral performance in auditory tasks. Together, these results underscore the critical role of early sensory experience in shaping brain structure and suggest that increased occipital cortical thickness, while potentially compensatory for auditory sensory processing, might be maladaptive for visual recovery in cases of sight restoration.


Assuntos
Catarata/patologia , Catarata/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Córtex Visual/patologia , Percepção Visual/fisiologia , Estimulação Acústica , Adolescente , Adulto , Análise de Variância , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Privação Sensorial/fisiologia , Estatística como Assunto , Visão Ocular/fisiologia , Adulto Jovem
8.
Brain ; 138(Pt 6): 1499-504, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25808371

RESUMO

Developmental vision is deemed to be necessary for the maturation of multisensory cortical circuits. Thus far, this has only been investigated in animal studies, which have shown that congenital visual deprivation markedly reduces the capability of neurons to integrate cross-modal inputs. The present study investigated the effect of transient congenital visual deprivation on the neural mechanisms of multisensory processing in humans. We used functional magnetic resonance imaging to compare responses of visual and auditory cortical areas to visual, auditory and audio-visual stimulation in cataract-reversal patients and normally sighted controls. The results showed that cataract-reversal patients, unlike normally sighted controls, did not exhibit multisensory integration in auditory areas. Furthermore, cataract-reversal patients, but not normally sighted controls, exhibited lower visual cortical processing within visual cortex during audio-visual stimulation than during visual stimulation. These results indicate that congenital visual deprivation affects the capability of cortical areas to integrate cross-modal inputs in humans, possibly because visual processing is suppressed during cross-modal stimulation. Arguably, the lack of vision in the first months after birth may result in a reorganization of visual cortex, including the suppression of noisy visual input from the deprived retina in order to reduce interference during auditory processing.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Privação Sensorial/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Adolescente , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Catarata/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
9.
J AAPOS ; 18(5): 461-465.e1, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25439303

RESUMO

PURPOSE: To describe an ophthalmic phenotype in children at relatively early stages of Wolfram syndrome. METHODS: Quantitative ophthalmic testing of visual acuity, color vision, automated visual field sensitivity, optic nerve pallor and cupping, and retinal nerve fiber layer (RNFL) thickness assessed by optical coherence tomography (OCT) was performed in 18 subjects 5-25 years of age. Subjects were also examined for presence or absence of afferent pupillary defects, cataracts, nystagmus, and strabismus. RESULTS: Subnormal visual acuity was detected in 89% of subjects, color vision deficits in 94%, visual field defects in 100%, optic disk pallor in 94%, abnormally large optic nerve cup:disk ratio in 33%, thinned RNFL in 100%, afferent pupillary defects in 61%, cataracts in 22%, nystagmus in 39%, and strabismus in 39% of subjects. RNFL thinning (P < 0.001), afferent pupillary defects (P = 0.01), strabismus (P = 0.04), and nystagmus (P = 0.04) were associated with more severe disease using the Wolfram United Rating Scale. CONCLUSIONS: Children and adolescents with Wolfram syndrome have multiple ophthalmic markers that correlate with overall disease severity. RNFL thickness measured by OCT may be the most reliable early marker.


Assuntos
Oftalmopatias/diagnóstico , Síndrome de Wolfram/diagnóstico , Adolescente , Adulto , Catarata/diagnóstico , Catarata/fisiopatologia , Criança , Pré-Escolar , Visão de Cores/fisiologia , Oftalmopatias/fisiopatologia , Feminino , Humanos , Masculino , Fibras Nervosas/patologia , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/fisiopatologia , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/fisiopatologia , Fenótipo , Distúrbios Pupilares/diagnóstico , Distúrbios Pupilares/fisiopatologia , Células Ganglionares da Retina/patologia , Índice de Gravidade de Doença , Tomografia de Coerência Óptica , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia , Campos Visuais/fisiologia , Síndrome de Wolfram/fisiopatologia , Adulto Jovem
10.
Neurology ; 83(15): 1337-44, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25186864

RESUMO

OBJECTIVE: We describe the 10-year follow-up in a cohort of 16 patients with genetically confirmed congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) syndrome, providing new insights in the clinical course of the disease. METHODS: We performed a detailed clinical and paraclinical characterization and 10-year follow-up study in 16 patients with molecularly defined CCFDN syndrome, illustrating that CCFDN is a severe disabling disorder. RESULTS: All patients initially presented with congenital cataracts along with strabismus, facial dysmorphism, short stature, and demyelinating neuropathy. In all patients, paresis of small hand muscles and foot extensors worsened with disease progression, while ataxia scores remained stable or improved. Nerve conduction velocity was normal in early infancy up to 18 months, decreased to approximately 20 m/s around age 10 years, and then remained stable; distal motor latency was prolonged. Sensory nerve conduction velocities were slowed, and initially of normal amplitude. With disease progression, both sensory and motor nerves showed reduction of amplitudes indicating axonal loss. In 6 patients, acute severe proximal weakness and myalgia after febrile infections, along with rhabdomyolysis, myoglobinuria, and hyperCKemia, led to a less favorable outcome and permanent loss of ambulation in 3 patients. CONCLUSIONS: CCFDN should be classified as a recessive demyelinating sensory-motor neuropathy, and axonal loss is a major determinant of long-term outcomes and disability. Patients benefit from early and ongoing physiotherapy, and should be thoroughly counseled regarding virus-triggered rhabdomyolysis and the risk of malignant hyperthermia. Whether supplementation with liposoluble vitamins results in a therapeutic benefit should be evaluated in further studies.


Assuntos
Catarata/congênito , Anormalidades Craniofaciais/diagnóstico , Doenças do Sistema Nervoso/diagnóstico , Adolescente , Adulto , Catarata/diagnóstico , Catarata/fisiopatologia , Criança , Pré-Escolar , Anormalidades Craniofaciais/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Lactente , Masculino , Neurônios Motores/fisiologia , Doenças do Sistema Nervoso/fisiopatologia , Condução Nervosa/fisiologia , Células Receptoras Sensoriais/fisiologia , Avaliação de Sintomas , Adulto Jovem
11.
Can J Ophthalmol ; 49(2): 141-4, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767218

RESUMO

OBJECTIVE: To research the effects of sub-Tenon's anaesthesia (STA) on ocular hemodynamics in patients with cataract using colour Doppler imaging (CDI). DESIGN: Prospective clinical study. PARTICIPANTS: Thirty-four eyes of 34 patients with age-related cataract. METHODS: Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) values of the ophthalmic artery (OA), central retinal artery, and central retinal vein were measured by CDI before and immediately after performing sub-Tenon block using 2 mL of 2% lidocaine with adrenaline (1:200 000). RESULTS: Both PSV and EDV values were significantly decreased after sub-Tenon injection in all the studied vessels of the patients. However, no important changes were observed in the RI values of the vessels. CONCLUSIONS: STA markedly reduced ocular blood flow. The reduction may be more acceptable compared with other retrobulbar block methods. Sub-Tenon block should be performed carefully to senile patients with cataract with vascular occlusive disorder.


Assuntos
Anestesia Local/métodos , Catarata/fisiopatologia , Artéria Oftálmica/fisiologia , Artéria Retiniana/fisiologia , Veia Retiniana/fisiologia , Cápsula de Tenon/efeitos dos fármacos , Idoso , Anestésicos Locais/administração & dosagem , Velocidade do Fluxo Sanguíneo/fisiologia , Epinefrina/administração & dosagem , Feminino , Humanos , Lidocaína/administração & dosagem , Masculino , Midriáticos/administração & dosagem , Estudos Prospectivos , Ultrassonografia Doppler em Cores
12.
Ophthalmology ; 121(6): 1229-36, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24613825

RESUMO

OBJECTIVE: To evaluate visual acuity outcomes after cataract surgery in persons with varying degrees of severity of age-related macular degeneration (AMD). DESIGN: Cohort study. PARTICIPANTS: A total of 1232 eyes of 793 participants who underwent cataract surgery during the Age-Related Eye Disease Study 2, a prospective, multicenter, randomized controlled trial of nutritional supplements for treatment of AMD. METHODS: Preoperative and postoperative characteristics of participants who underwent cataract extraction during the 5-year trial were analyzed. Both clinical data and standardized red-reflex lens and fundus photographs were obtained at baseline and annually. Photographs were graded by a centralized reading center for cortical and posterior subcapsular lens opacities and for AMD severity. Cataract surgery was documented at annual study visits or by history during the 6-month telephone calls. Analyses were conducted using multivariate repeated-measures regression. MAIN OUTCOME MEASURES: Change in best-corrected visual acuity (BCVA) after cataract surgery compared with preoperative BCVA. RESULTS: Adjusting for age at time of surgery, gender, interval between preoperative and postoperative visits, and type and severity of cataract, the mean changes in visual acuity were as follows: eyes with mild AMD (n = 30) gained 11.2 letters (95% confidence interval [CI], 6.9-15.5), eyes with moderate AMD (n = 346) gained 11.1 letters (95% CI, 9.1-13.2), eyes with severe AMD (n = 462) gained 8.7 letters (95% CI, 6.7-10.7), eyes with noncentral geographic atrophy (n = 70) gained 8.9 letters (95% CI, 5.8-12.1), and eyes with advanced AMD (central geographic atrophy, neovascular disease, or both; n = 324) gained 6.8 letters (95% CI, 4.9-8.8). The visual acuity gain across all AMD severity groups was statistically significant from preoperative values (P < 0.0001). CONCLUSIONS: Mean visual acuities improved significantly after cataract surgery across varying degrees of AMD severity.


Assuntos
Implante de Lente Intraocular , Degeneração Macular/fisiopatologia , Facoemulsificação , Pseudofacia/fisiopatologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Catarata/fisiopatologia , Estudos de Coortes , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Humanos , Luteína/administração & dosagem , Degeneração Macular/classificação , Degeneração Macular/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Vitaminas/administração & dosagem , Xantofilas/administração & dosagem , Zeaxantinas
13.
Biochimie ; 95(10): 1811-27, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23764390

RESUMO

Several inositol isomers and in particular myo-inositol (MI) and D-chiro-inositol (DCI), were shown to possess insulin-mimetic properties and to be efficient in lowering post-prandial blood glucose. In addition, abnormalities in inositol metabolism are associated with insulin resistance and with long term microvascular complications of diabetes, supporting a role of inositol or its derivatives in glucose metabolism. The aim of this review is to focus on the potential benefits of a dietary supplement of myo-inositol, by far the most common inositol isomer in foodstuffs, in human disorders associated with insulin resistance (polycystic ovary syndrome, gestational diabetes mellitus or metabolic syndrome) or in prevention or treatment of some diabetic complications (neuropathy, nephropathy, cataract). The relevance of such a nutritional strategy will be discussed for each context on the basis of the clinical and/or animal studies. The dietary sources of myo-inositol and its metabolism from its dietary uptake to its renal excretion will be also covered in this review. Finally, the actual insights into inositol insulin-sensitizing effects will be addressed and in particular the possible role of inositol glycans as insulin second messengers.


Assuntos
Catarata/metabolismo , Diabetes Gestacional/metabolismo , Nefropatias Diabéticas/metabolismo , Inositol/metabolismo , Síndrome Metabólica/metabolismo , Síndrome do Ovário Policístico/metabolismo , Animais , Glicemia/metabolismo , Catarata/fisiopatologia , Catarata/prevenção & controle , Diabetes Gestacional/dietoterapia , Diabetes Gestacional/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/prevenção & controle , Dieta , Feminino , Humanos , Inositol/administração & dosagem , Inositol/farmacocinética , Insulina/metabolismo , Resistência à Insulina , Síndrome Metabólica/dietoterapia , Síndrome Metabólica/fisiopatologia , Síndrome do Ovário Policístico/dietoterapia , Síndrome do Ovário Policístico/fisiopatologia , Gravidez
14.
JAMA Ophthalmol ; 131(7): 843-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23645227

RESUMO

IMPORTANCE: Age-related cataract is a leading cause of visual impairment in the United States. The prevalence of age-related cataract is increasing, with an estimated 30.1 million Americans likely to be affected by 2020. OBJECTIVE: To determine whether daily oral supplementation with lutein/zeaxanthin affects the risk for cataract surgery. DESIGN, SETTING, AND PATIENTS: The Age-Related Eye Disease Study 2 (AREDS2), a multicenter, double-masked clinical trial, enrolled 4203 participants, aged 50 to 85 years, at risk for progression to advanced age-related macular degeneration. INTERVENTIONS: Participants were randomly assigned to daily placebo; lutein/zeaxanthin, 10mg/2mg; omega-3 long-chain polyunsaturated fatty acids, 1 g; or a combination to evaluate the effects on the primary outcome of progression to advanced age-related macular degeneration. MAIN OUTCOMES AND MEASURES: Cataract surgery was documented at annual study examination with the presence of pseudophakia or aphakia, or reported during telephone calls at 6-month intervals between study visits. Annual best-corrected visual acuity testing was performed. A secondary outcome of AREDS2 was to evaluate the effects of lutein/zeaxanthin on the subsequent need for cataract surgery. RESULTS: A total of 3159 AREDS2 participants were phakic in at least 1 eye and 1389 of 6027 study eyes underwent cataract surgery during the study, with median follow-up of 4.7 years. The 5-year probability of progression to cataract surgery in the no lutein/zeaxanthin group was 24%. For lutein/zeaxanthin vs no lutein/zeaxanthin, the hazard ratios for progression to cataract surgery was 0.96 (95% CI, 0.84-1.10; P = .54). For participants in the lowest quintile of dietary intake of lutein/zeaxanthin, the hazard ratio comparing lutein/zeaxanthin vs no lutein/zeaxanthin for progression to cataract surgery was 0.68 (95% CI, 0.48-0.96; P = .03). The hazard ratio for 3 or more lines of vision loss was 1.03 (95% CI, 0.93-1.13; P = .61 for lutein/zeaxanthin vs no lutein/zeaxanthin). CONCLUSIONS AND RELEVANCE: Daily supplementation with lutein/zeaxanthin had no statistically significant overall effect on rates of cataract surgery or vision loss. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00345176.


Assuntos
Envelhecimento , Extração de Catarata/estatística & dados numéricos , Catarata/tratamento farmacológico , Luteína/uso terapêutico , Xantofilas/uso terapêutico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Catarata/diagnóstico , Catarata/fisiopatologia , Suplementos Nutricionais , Progressão da Doença , Método Duplo-Cego , Quimioterapia Combinada , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Humanos , Luteína/sangue , Masculino , Transtornos da Visão/diagnóstico , Acuidade Visual , Xantofilas/sangue , Zeaxantinas
15.
J Cataract Refract Surg ; 39(5): 804-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23465649

RESUMO

We present a case of extreme positioning for cataract surgery. The 68-year-old man was unable to lie flat and found it difficult to transfer from his motorized wheelchair. He had poor mobility due to a stroke, slept upright because of orthopnea, and his neck extension was poor. After the options and risks were discussed, surgery was performed under topical intracameral anesthesia using face-to-face positioning with the patient seated upright in his wheelchair. The operating microscope was rotated toward the horizontal, and the surgeon stood at the patient's side with the patient's face almost upright. The right-handed surgeon used a temporal corneal incision (0 degree) in the left eye and an inferior incision (270 degrees) in the right eye. Surgery and recovery were uneventful. Given a preexisting epiretinal membrane in the left eye, the patient was very happy with the uncorrected distance visual acuity outcome of 6/9 in the right eye and 6/18 in the left eye.


Assuntos
Implante de Lente Intraocular/métodos , Posicionamento do Paciente/métodos , Facoemulsificação/métodos , Pessoas com Deficiência Visual , Cadeiras de Rodas , Idoso , Anestesia Local , Catarata/complicações , Catarata/fisiopatologia , Humanos , Masculino , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia
16.
Ophthalmology ; 120(3): 482-488, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23207175

RESUMO

PURPOSE: To compare the outcomes of 2 intraocular lenses (IOLs) for the treatment of age-related cataracts. DESIGN: Prospective, randomized trial. PARTICIPANTS: Patients with age-related cataracts were recruited and randomized to receive phacoemulsification and implantation of either the AcrySof SA60AT lens (Alcon, Inc, Fort Worth, TX) or the low-cost Tecsoft Flex lens (Fred Hollows Foundation, Tilganga, Nepal). A total of 300 patients were available for description and analysis (148 in the AcrySof group and 152 in the Tecsoft group). METHODS: Patients underwent phacoemulsification and implantation of the AcrySof SA60AT lens or the Tecsoft Flex lens. They were followed up and examined at baseline, 1 week, 1 month, 6 months, and 12 months after cataract surgery. MAIN OUTCOME MEASURES: Uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BDVA), incidence of posterior capsule opacification (PCO), Visual Function Index questionnaire results, and safety of the implanted IOLs. RESULTS: No significant difference (P>0.05) was found in UDVA and BDVA after surgery between the 2 groups. The equivalence test of the 95% confidence intervals showed that both lenses had an equal improvement of UDVA and BDVA as well as similar rates of PCO after cataract surgery. There was no significant difference between the 2 groups with regard to visual functioning or the incidence of adverse surgical events during (P>0.05) or after (P>0.05) the surgery. CONCLUSIONS: The Tecsoft Flex IOL is a low-cost suitable alternative that is similar to the AcrySof IOL in terms of safety and visual outcomes.


Assuntos
Materiais Biocompatíveis , Implante de Lente Intraocular , Lentes Intraoculares , Facoemulsificação , Idoso , Envelhecimento/fisiologia , Opacificação da Cápsula/etiologia , Catarata/fisiopatologia , Catarata/reabilitação , Feminino , Seguimentos , Humanos , Masculino , Cápsula Posterior do Cristalino/patologia , Estudos Prospectivos , Desenho de Prótese , Qualidade de Vida , Refração Ocular/fisiologia , Perfil de Impacto da Doença , Resultado do Tratamento , Acuidade Visual/fisiologia , Pessoas com Deficiência Visual/reabilitação
17.
Trials ; 12: 148, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21672204

RESUMO

BACKGROUND: The Italian-American Clinical Trial of Nutritional Supplements and Age-Related Cataract was designed to assess the impact of a multivitamin-mineral supplement on age-related cataract. Trial results showed evidence of a beneficial effect of the supplement on all types of cataract combined, opposite effects on two of the three types of cataract (beneficial for nuclear opacities and harmful for posterior sub-capsular opacities) and no statistically significant effect on cortical opacities. No treatment recommendations were made. A post-trial survey was conducted on 817 surviving elderly participants to assess their satisfaction, their understanding of treatment assignment to supplement or placebo and the success of masking. METHODS: Trial results were communicated by letter and the level of satisfaction and of understanding of the results was assessed by a questionnaire. Participants were offered the option of being unmasked: a second questionnaire was administered to this subset to assess their understanding of the randomisation process and the success of masking. RESULTS: 610 participants (74.7%) responded to the survey:94.6% thought the description of the results was "very clear" or "quite clear", 5.4% "not clear" or "do not know"; 89.8% considered the results "very interesting" or "quite interesting", 10.2% "not interesting" or "do not know"; 60.3% expressed "satisfaction", 17.2% "both satisfaction and concern", 2.6% "concern", 19.9% "indifference" or "do not know".480 participants (78.7%) accepted the offer to be unmasked to their treatment assignment: 395 (82.3%) recalled/understood the possibility of assignment to vitamins or placebo, 85 (17.7%) did not. 68 participants (17.2%) thought they had taken vitamins (79.4% were correct; p = 0.0006), 47 (11.9%) thought they had taken placebo (59.6% were correct; p = 0.46) and 280 (70.9%) declared they did not know. CONCLUSIONS: The results were made difficult to explain to study participants by the qualitatively different effect of treatment on the two most visually significant types of cataract. Although the study did not lead to a recommendation to use the dietary supplement, the vast majority of participants reported satisfaction after they received the results but almost 20% of the participants expressed some concern. Masking to treatment assignment was successful in the majority of participants.


Assuntos
Catarata/tratamento farmacológico , Correspondência como Assunto , Suplementos Nutricionais , Disseminação de Informação , Minerais/uso terapêutico , Projetos de Pesquisa , Vitaminas/uso terapêutico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Catarata/diagnóstico , Catarata/fisiopatologia , Distribuição de Qui-Quadrado , Compreensão , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Minerais/efeitos adversos , Satisfação do Paciente , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Vitaminas/efeitos adversos
18.
Exp Eye Res ; 92(2): 120-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21147102

RESUMO

Cataract-related loss of vision affects large numbers of people in today's aging populations and presents a healthcare burden to many nations. The role of dietary supplements within the lens is largely unknown, although benefits from dietary anti-oxidants are expected. In this study, the effects of genistein as its aglycone, a genistein-containing dietary supplement (Novasoy(®)200), and a genistein-containing food (soy protein isolate, PRO-FAM 932) on the development of lens opacity were examined in the hereditary cataractous ICR/f rat. These studies were carried out in a background diet of semi-purified, isoflavone-free AIN-76A with casein as its protein source. The amount of genistein for the experimental diets was standardized to its concentration (as genistein aglycone as well as simple and complex ß-glucoside conjugates) in the soy protein isolate supplement. Also tested was a high-dose genistein diet containing an 11-fold higher amount of genistein aglycone. The composition of each diet was verified by reverse-phase HPLC and blood plasma isoflavone concentrations were determined by LC-tandem mass spectrometry. The development of opacity in each lens was monitored and digitally recorded using slit-lamp examination over the course of the study. Each of the genistein-containing diets caused a significantly more rapid development of fibrous opacification in the anterior cortical region and development of apparent water clefts or vacuoles in the posterior subcapsular region than the AIN-76A control diet; however, the establishment of dense lens opacification was not significantly different between each of the diets. There was also no significant difference observed between the low-dose and high-dose genistein aglycone groups. These data suggest that genistein-containing dietary supplements accelerate the early stages of cataractogenesis in the male ICR/f rat, with no dose-dependent effects.


Assuntos
Catarata/induzido quimicamente , Catarata/fisiopatologia , Suplementos Nutricionais/toxicidade , Genisteína/toxicidade , Cristalino/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Catarata/classificação , Cromatografia Líquida de Alta Pressão , Genisteína/sangue , Isoflavonas/sangue , Masculino , Ratos , Proteínas de Soja/química , Espectrometria de Massas em Tandem
19.
Ophthalmic Surg Lasers Imaging ; 41(3): 337-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20507018

RESUMO

BACKGROUND AND OBJECTIVE: To investigate the subjective visual experience of patients with concurrent cataract and glaucoma during phacoemulsification-trabeculectomy under peribulbar anesthesia. PATIENTS AND METHODS: Consecutive patients with concurrent cataract and glaucoma who underwent phacoemulsification-trabeculectomy under peribulbar anesthesia for the first time were interviewed using a standardized questionnaire between 30 minutes and 4 hours after the surgery. They were asked about their intraoperative visual experiences and their reaction to their visual experience. There was no preoperative discussion with the patients on possible intraoperative visual sensations that they might experience. No preoperative or intraoperative sedation was used. RESULTS: Sixty patients with a mean age of 64.8 years (range: 41 to 86 years) were included in the study. Light perception was reported by 73.3% of patients and no light perception by 26.7% throughout the operation. Some patients reported they could also see movements (65%), flashes (53.3%), one or more colors (48.3%), a change in light brightness (38.3%), instruments (8.3%), and/or the surgeon/medical staff (1.7%). Of the 29 patients (48.3%) who saw one or more colors, 18 patients saw yellow, 12 blue, 4 green, 2 orange, and 1 red. One patient (1.7%) found the visual experience frightening and the rest (98.3%) found theirs pleasant. CONCLUSION: The majority of patients with concurrent cataract and glaucoma undergoing phacoemulsification-trabeculectomy using peribulbar anesthesia experience a variety of visual sensations, although only a minority was frightened by the visual experience.


Assuntos
Anestesia Local/métodos , Catarata/complicações , Glaucoma/complicações , Monitorização Intraoperatória/métodos , Facoemulsificação/métodos , Trabeculectomia/métodos , Acuidade Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Catarata/fisiopatologia , Feminino , Glaucoma/fisiopatologia , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Órbita , Resultado do Tratamento
20.
Am J Ther ; 17(4): 373-89, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20463577

RESUMO

Cataract, opacification of the lens, is one of the commonest causes of loss of useful vision during aging, with an estimated 16 million people world-wide affected. The role of nutritional supplementation in prevention of onset or progression of ocular disease is of interest to health care professionals and patients. The aging eye seems to be at considerable risk from oxidative stress. This review outlines the potential role of the new nutritional strategy on redox balance in age-related eye diseases and detail how the synergism and interaction of imidazole-containing amino acid-based compounds (nonhydrolized L-carnosine, histidine), chaperone agents (such as, L-carnosine, D-pantethine), glutathione-boosting agents (N-acetylcysteine, vitamin E, methionine), and N-acetylcarnosine eye drops plays key roles in the function and maintenance of the redox systems in the aging eye and in the treatment of human cataract disease. A novel patented oral health supplement is presented which enhances the anticataract activity of eye drops and activates functional visual acuity. The clinical data demonstrate the effectiveness and safety of a combined oral health care treatment with amino acids possessing chaperone-like activity with N-acetylcarnosine lubricant eye drops. L-carnosine and N-acetylcarnosine protected the chaperone activity of alpha-crystallin and reduced the increased posttranslational modifications of lens proteins. Biological activities of the nonhydrolyzed carnosine in the oral formulation are based on its antioxidant and antiglycating (transglycating) action that, in addition to heavy metal chelation and pH-buffering ability, makes carnosine an essential factor for preventing sight-threatening eye disorders having oxidative stress in their pathogenesis, neurodegeneration, and accumulation of senile features. The findings suggest that synergism is required between carnosine or other imidazole-containing compounds and reduced glutathione in tissues and cells for efficacious protection from protein carbonylation as a biomarker for the ability of the non-toxic compounds to reduce oxidative stress. Potential therapeutic applications of oral forms of nonhydrolized carnosine and their specific mechanisms to manage telomere attrition and vascular aging might help elderly patients to withstand the problems of sight-threatening eye diseases related to oxidative stress and accelerated biological ageing in linked with earlier onset of diseases.


Assuntos
Aminoácidos/uso terapêutico , Antioxidantes/uso terapêutico , Catarata/tratamento farmacológico , Envelhecimento , Aminoácidos/administração & dosagem , Aminoácidos/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Catarata/fisiopatologia , Suplementos Nutricionais , Sinergismo Farmacológico , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Chaperonas Moleculares/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
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