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1.
Ophthalmic Physiol Opt ; 44(6): 1202-1214, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38818867

RESUMO

PURPOSE: Lens power profiles can provide valuable insights on the imposed optical defocus and visual experience of contact lens wearers, especially in the context of myopia control. This study measured the refractive power profiles of multifocal soft contact lenses (MFCLs) currently used or that have the potential for use in myopia control using high spatial resolution aberrometry. The instrument's repeatability for determining MFCLs power profiles was also assessed. METHOD: The power profiles of 10 MFCLs of various designs (centre-distance, centre-near and extended depth of focus) were measured using the Lambda-X NIMOEVO, a phase shifting Schlieren-based device. Power profiles were graphically expressed as measured power at each chord position and the maximum add power was calculated. The repeatability of the NIMOEVO was expressed as the within-subject standard deviation at each chord position for a subset of five MFCLs. RESULTS: The measured distance powers differed from nominal powers for more than half of the MFCLs with a definable distance zone. There were variations in the chord position of the distance and near correction zones, rate of power transitions and calculated maximum add between the MFCLs which did not depend on lens design. For half of the MFCLs, the power profile shape was inconsistent between different nominal back vertex powers of the same design. The repeatability of the NIMOEVO was dependent on the lens design, with designs featuring faster rates of power change exhibiting worse repeatability. CONCLUSIONS: Significant differences in MFCL power profiles were found which were not adequately represented in labelling. This is likely due to the small number of parameters used to define lens power characteristics. Eye health care practitioners should be aware of potential differences in power profiles between different MFCLs, which will impact the retinal defocus introduced during lens wear and the wearer's visual experience.


Assuntos
Lentes de Contato Hidrofílicas , Miopia , Refração Ocular , Humanos , Miopia/fisiopatologia , Miopia/terapia , Refração Ocular/fisiologia , Adulto , Reprodutibilidade dos Testes , Desenho de Equipamento , Aberrometria , Masculino , Feminino
2.
Optom Vis Sci ; 93(4): 367-76, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26784709

RESUMO

This review highlights the current state of knowledge of in vivo testing of drug-delivering contact lenses. There has been a significant increase in interest in alternative means to deliver ocular pharmaceuticals, and within the past few decades, contact lenses have emerged as a vehicle of interest because of their biocompatibility and acceptance by both eye care professionals and the public. Using techniques such as molecular imprinting, vitamin E diffusion barriers, ionic reservoirs, and drug-impregnated films, significantly improved drug release kinetics have been observed in vitro. Extension of these results into in vivo studies has thus far been limited but has led to evidence of the viability of this drug delivery platform by demonstrating improved drug residence time, drug penetration, and clinical outcomes when compared with conventional therapy such as eye drops. The evidence supporting these improvements has occurred in both animal models and small human trials and is presented within this review.


Assuntos
Lentes de Contato , Sistemas de Liberação de Medicamentos , Soluções Oftálmicas/administração & dosagem , Preparações Farmacêuticas/administração & dosagem , Animais , Materiais Biocompatíveis , Oftalmopatias/tratamento farmacológico , Humanos , Desenho de Prótese
3.
J Gastroenterol Hepatol ; 29(1): 116-20, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24033786

RESUMO

BACKGROUND AND AIM: Chronic hepatitis C virus (HCV) infection is one of the leading causes of cirrhosis and hepatocellular carcinoma worldwide. It is highly prevalent among injection drug users (IDUs) but is often undiagnosed because they represent an underprivileged group that faces multiple barriers to medical care. Here, we report the results of the New Life New Liver Project, which provides targeted HCV screening and education for ex-IDUs in the community. METHODS: Patients were recruited through the social worker networks and referrals by fellow ex-IDUs, and rapid diagnosis was based on point-of-care anti-HCV testing at rehabilitation centers. RESULTS: From 2009 to 2012, we served 234 subjects. One hundred thirty (56%) subjects were anti-HCV positive. The number needed to screen to detect one patient with positive anti-HCV was 1.8 (95% confidence interval, 1.6-2.0). However, only 69 (53%) HCV patients attended subsequent follow-up at regional hospitals, and 26 (20%) received antiviral therapy. Patients who attended follow-up were older, had higher education level and more active disease as evidenced by higher alanine aminotransferase, HCV RNA, and liver stiffness measurement by transient elastography. CONCLUSIONS: Targeted screening in ex-IDUs is effective in identifying patients with HCV infection in the community. Improvement in the referral system and introduction of interferon-free regimens are needed to increase treatment uptake.


Assuntos
Serviços de Saúde Comunitária , Usuários de Drogas/estatística & dados numéricos , Hepatite C/diagnóstico , Programas de Rastreamento/métodos , Alanina Transaminase , Biomarcadores , Redes Comunitárias , Técnicas de Imagem por Elasticidade , Feminino , Seguimentos , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Sistemas Automatizados de Assistência Junto ao Leito , RNA Viral , Índice de Gravidade de Doença
4.
J Clin Med ; 13(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999403

RESUMO

Scleral lenses (SLs) are large-diameter rigid contact lenses that are a mainstay treatment for eyes with corneal irregularities. In recent years, there has been increased interest in the role of managing dry eye disease (DED) with SLs, as many patients with DED have reported symptomatic relief with SL wear. The role of SLs for DED management when there are associated corneal irregularities is supported by individual case reports and studies. This has prompted practitioners to begin advocating using SLs in DED cases, even in the absence of associated corneal irregularities and other ocular surface diseases (OSDs). There have also been discussions on potentially placing SLs earlier in the treatment hierarchy of DED, where it currently sits at a more advanced level of intervention (Step 3) in the TFOS DEWS II Report. This review will present the currently available, albeit sparse, evidence that supports and suggests this practice, as well as ancillary evidence supporting the purported benefits of SL wear in DED. The advantages of SL wear, such as corneal healing, absence of tear evaporation and contact lens dehydration, and improved visual acuity with associated increased wear comfort, and how this will benefit DED patients will be explored. Conversely, the challenges associated with fitting SLs in DED patients, including increased midday fogging, poor wettability, and subjective patient satisfaction, will also be presented, as well as a discussion on the key considerations for SL fitting in this population. Overall, while more research is needed to support the use of SLs in DED patients without associated corneal irregularities and other forms of OSD, the use of these lenses may prove to have a potentially wider role given their reported ancillary benefits in these populations.

5.
Curr Eye Res ; 49(10): 1012-1020, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38780797

RESUMO

PURPOSE: This study examines the incidence of infection and resistance associated with Intracorneal Ring Segment (ICRS) implantation, a common outpatient surgical treatment for correcting refractive errors and corneal ectatic diseases. Although ICRS procedures are typically safe and reversible, there is a low but notable risk of microbial infections, which require prompt and sometimes invasive treatment. METHODS: Three electronic databases, PubMed, Web of Science (WoS), and Scopus, were utilised to search for literature according to PRISMA guidelines to identify infections related to the implantation of ICRS in the cornea between January 2000 and December 2022. RESULTS: Gram-positive organisms were involved in 86% of cases: 35.7% S. aureus, 25% coagulase-negative staphylococci species, 17.8% streptococci and 7.1% Nocardia species. Less commonly recorded were Gram-negative bacteria (14%), with Pseudomonas aeruginosa (circa 10%) and Klebsiella pneumonia (4%) being the most common Gram-negative bacteria. In rare cases, fungi have also been reported. ICRS-related bacterial infections can be categorised into early or late onset. Early onset infection typically manifests within the first few weeks after implantation and is often associated with contamination during surgery, unhygienic practices, or inadequate sterilisation techniques. On the other hand, late-onset infection may develop months or even years after the initial procedures and may be associated with persistent bacterial colonisation, secondary infections, or prolonged use of prophylactic antibiotics. S aureus is encountered in both early and late-onset infections, while Nocardia species and K. pneumoniae have generally been reported to occur in late-onset infections. In addition, vision recovery from S. aureus infections tends to be poor compared to other bacterial infections. CONCLUSION: S. aureus is a predominant pathogen that often requires surgical intervention with poor outcomes. Early infections result from incision gaps and ring segment rubbing, while late infections are linked to prolonged antibiotic use. Further research is needed on novel antimicrobial ICRS to procure the vision.


Assuntos
Substância Própria , Infecções Oculares Bacterianas , Implantação de Prótese , Infecções Relacionadas à Prótese , Humanos , Infecções Oculares Bacterianas/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Substância Própria/microbiologia , Substância Própria/cirurgia , Incidência , Antibacterianos/uso terapêutico , Próteses e Implantes/microbiologia , Próteses e Implantes/efeitos adversos , Bactérias/isolamento & purificação , Ceratocone/cirurgia
6.
Cont Lens Anterior Eye ; : 102246, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38851947

RESUMO

PURPOSE: Myopia (short-sightedness) is a growing vision problem worldwide. Currently atropine eye drops are used to control the progression of myopia but these suffer from potential lack of bioavailability and low ocular residence time. Commercially available myopia control contact lenses are also used to limit myopia progression, but neither atropine nor contact lenses individually completely stop progression. Development of myopia control contact lenses which could deliver therapeutic doses of atropine is thus desirable and may provide increased efficacy. This study was designed to explore the feasibility of attaching atropine to etafilcon A contact lenses through an esterification reaction. METHODS: Carboxylic acid groups on etafilcon A contact lenses were quantified using Toluidine Blue O. The carboxylic acid groups in etafilcon A contact lenses were activated using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC-HCl) and N-hydroxysuccinimide (NHS) crosslinkers after which atropine was added to undergo potential binding via esterification. Atropine was released from lenses by alkaline hydrolysis. Reverse phase high performance liquid chromatography (HPLC) was used to detect and quantify the released atropine and its degradation products in solution. Contact lenses that had not been activated by EDC-NHS (controls) were also examined to determine the amount of atropine that could be absorbed rather than chemically bound to lenses. RESULTS: Each etafilcon A contact lens contained 741.1 ± 5.5 µg carboxylic acid groups which may be available for esterification. HPLC had a limit of detection for atropine of 0.38 µg/mL and for tropic acid, an atropine degradation product, of 0.80 µg/mL. The limits of quantification were 1.16 µg/mL for atropine and 2.41 µg/mL for tropic acid in NH4HCO3. The etafilcon A lenses adsorbed up to 7.69 µg atropine when incubated in a 5 mg/mL atropine solution for 24 h. However, there was no evidence that atropine could be chemically linked to the lenses, as washing in a high concentration of NaCl removed all the atropine from the contact lenses with no atropine being subsequently released from the lenses after incubating in 0.01 N NH4HCO3. CONCLUSIONS: Etafilcon A contact lenses contain free carboxylic acids which may be an appropriate option for attaching drugs such as atropine. Etafilcon A lenses adsorbed up to 7.69 µg atropine, which would be more than enough to deliver atropine to eyes to control myopia. However, atropine could not be chemically bound to the carboxylic acids of the etafilcon A lenses using this methodology.

7.
Cont Lens Anterior Eye ; 47(2): 102104, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38161140

RESUMO

PURPOSE: The purpose of this study was to explore the impact of several contact lens (CL) care solutions on the removal of proteins and lipids, and how deposit removal impacts bacterial adhesion and solution disinfection. METHODS: Lysozyme and lipid deposition on three ortho-k (rigid) and two soft CL materials were evaluated using an ELISA kit and gas chromatography respectively. Bacterial adhesion to a fluorosilicone acrylate material using Pseudomonas aeruginosa with various compositions of artificial tear solutions (ATS), including with denatured proteins, was also investigated. The impact of deposition of the different formulations of ATS on biofilm formation was explored using cover slips. Finally, the lysozyme and lipid cleaning efficacy and disinfection efficacy against P. aeruginosa and Staphylococcus aureus of four different contact lens care solutions were studied using qualitative analysis. RESULTS: While maximum lysozyme deposition was observed with the fluorosilicone acrylate material (327.25 ± 54.25 µg/lens), the highest amount of lipid deposition was recorded with a fluoro-siloxanyl styrene material (134.71 ± 19.87 µg/lens). Adhesion of P. aeruginosa to fluorosilicone acrylate lenses and biofilm formation on cover slips were significantly greater with the addition of denatured proteins and lipids. Of the four contact lens care solutions investigated, the solution based on povidone-iodine removed both denatured lysozyme and lipid deposits and could effectively disinfect against P. aeruginosa and S. aureus when contaminated with denatured proteins and lipids. In contrast, the peroxide-based solution was able to inhibit P. aeruginosa growth only, while the two multipurpose solutions were unable to disinfect lenses contaminated with denatured proteins and lipids. CONCLUSION: Bacterial adhesion and biofilm formation is influenced by components within artificial tear solutions depositing on lenses, including denatured proteins and lipids, which also affects disinfection. The ability of different solutions to remove these deposits should be considered when selecting systems to clean and disinfect ortho-k lenses.


Assuntos
Lentes de Contato Hidrofílicas , Muramidase , Humanos , Lubrificantes Oftálmicos , Aderência Bacteriana , Staphylococcus aureus , Proteínas , Soluções para Lentes de Contato/farmacologia , Lipídeos/análise , Acrilatos
8.
Clin Exp Optom ; 107(2): 156-170, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37879342

RESUMO

Traditional Chinese Medicine has a long history in ophthalmology in China. Over 250 kinds of Traditional Chinese Medicine have been recorded in ancient books for the management of eye diseases, which may provide an alternative or supplement to current ocular therapies. However, the core holistic philosophy of Traditional Chinese Medicine that makes it attractive can also hinder its understanding from a scientific perspective - in particular, determining true cause and effect. This review focused on how Traditional Chinese Medicine could be applied to two prevalent ocular diseases, glaucoma, and cataract. The literature on preclinical and clinical studies in both English and Chinese on the use of Traditional Chinese Medicine to treat these two diseases was reviewed. The pharmacological effects, safety profile, and drug-herb interaction of selected herbal formulas were also investigated. Finally, key considerations for conducting future Traditional Chinese Medicine studies are discussed.


Assuntos
Catarata , Glaucoma , Humanos , Medicina Tradicional Chinesa , China , Glaucoma/tratamento farmacológico
9.
Cont Lens Anterior Eye ; 47(2): 102124, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341309

RESUMO

BACKGROUND: Ocular infections caused by antibiotic-resistant pathogens can result in partial or complete vision loss. The development of pan-resistant microbial strains poses a significant challenge for clinicians as there are limited antimicrobial options available. Synthetic peptoids, which are sequence-specific oligo-N-substituted glycines, offer potential as alternative antimicrobial agents to target multidrug-resistant bacteria. METHODS: The antimicrobial activity of synthesised peptoids against multidrug-resistant (MDR) ocular pathogens was evaluated using the microbroth dilution method. Hemolytic propensity was assessed using mammalian erythrocytes. Peptoids were also incubated with proteolytic enzymes, after which their minimum inhibitory activity against bacteria was re-evaluated. RESULTS: Several alkylated and brominated peptoids showed good inhibitory activity against multidrug-resistant Pseudomonas aeruginosa strains at concentrations of ≤15 µg mL-1 (≤12 µM). Similarly, most brominated compounds inhibited the growth of methicillin-resistant Staphylococcus aureus at 1.9 to 15 µg mL-1 (12 µM). The N-terminally alkylated peptoids caused less toxicity to erythrocytes. The peptoid denoted as TM5 had a high therapeutic index, being non-toxic to either erythrocytes or corneal epithelial cells, even at 15 to 22 times its MIC. Additionally, the peptoids were resistant to protease activity. CONCLUSIONS: Peptoids studied here demonstrated potent activity against various multidrug-resistant ocular pathogens. Their properties make them promising candidates for controlling vision-related morbidity associated with eye infections by antibiotic-resistant strains.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Peptoides , Animais , Humanos , Peptoides/farmacologia , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Mamíferos
10.
Cont Lens Anterior Eye ; 47(2): 102129, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423868

RESUMO

PURPOSE: To evaluate the in vitro wettability and coefficient of friction of a novel amphiphilic polymeric surfactant (APS), poly(oxyethylene)-co-poly(oxybutylene) (PEO-PBO) releasing silicone hydrogel (SiHy) contact lens material (serafilcon A), compared to other reusable SiHy lens materials. METHODS: The release of fluorescently-labelled nitrobenzoxadiazole (NBD)-PEO-PBO was evaluated from serafilcon A over 7 days in a vial. The wettability and coefficient of friction of serafilcon A and three contemporary SiHy contact lens materials (senofilcon A; samfilcon A; comfilcon A) were evaluated using an in vitro blink model over their recommended wearing period; t = 0, 1, 7, 14 days for all lens types and t = 30 days for samfilcon A and comfilcon A (n = 4). Sessile drop contact angles were determined and in vitro non-invasive keratographic break-up time (NIKBUT) measurements were assessed on a blink model via the OCULUS Keratograph 5 M. The coefficient of friction was measured using a nano tribometer. RESULTS: The relative fluorescence of NBD-PEO-PBO decreased in serafilcon A by approximately 18 % after 7 days. The amount of NBD-PEO-PBO released on day 7 was 50 % less than the amount released on day 1 (6.5±1.0 vs 3.4±0.5 µg/lens). The reduction in PEO-PBO in the lens also coincided with an increase in contact angles for serafilcon A after 7 days (p < 0.05), although there were no changes in NIKBUT or coefficient of friction (p > 0.05). The other contact lens materials had stable contact angles and NIKBUT over their recommended wearing period (p > 0.05), with the exception of samfilcon A, which had an increase in contact angle after 14 days as compared to t = 0 (p < 0.05). Senofilcon A and samfilcon A also showed an increase in coefficient of friction at 14 and 30 days, respectively, compared to their blister pack values (p < 0.05). CONCLUSION: The results indicate that serafilcon A gradually depletes its reserve of PEO-PBO over 1 week, but this decrease did not significantly change the lens performance in vitro during this time frame.


Assuntos
Lentes de Contato Hidrofílicas , Silicones , Humanos , Molhabilidade , Hidrogéis , Fricção
11.
Optom Vis Sci ; 89(8): 1140-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22773177

RESUMO

PURPOSE: To investigate the uptake and delivery of the anti-allergy drug ketotifen fumarate (KF) by commercially available contact lenses. METHODS: A total of 14 different commercially available contact lenses were investigated, including five frequent-replacement silicone hydrogels, three conventional hydrogels, and six daily disposable lenses. Lenses were soaked in a 0.025% KF loading solution for 24 h, and the concentration of KF in solution over time was determined by ultraviolet absorbance at 297 nm. After the 24-h loading period, lenses were placed in fresh vials containing borate buffered saline, and the release of drug into solution at 34°C was monitored for 24 h. RESULTS: All the lenses studied demonstrated significant uptake and release of KF into the borate buffered saline (p < 0.05 compared with initial time point). Lenses with charged surfaces [balafilcon A, etafilcon A, and etafilcon A (daily disposable)] demonstrated the greatest uptake and release of KF. Etafilcon A released 284.5 ± 29.8 µg/lens, whereas balafilcon A released 227.6 ± 14.7 µg/lens, which was substantially more (p < 0.05) than the lowest releasing lenses [nelfilcon A (40.4 ± 4.1 µg/lens) and comfilcon A (110.4 ± 8.9 µg/lens)]. The majority of lenses were able to match or exceed the total amount of KF commonly administered to the eye using twice-daily dosing of commercially available (0.025%) eye drop formulations. Most of the lenses surveyed reached a plateau concentration of KF relatively quickly, and no lens was able to release KF for longer than 4 h. CONCLUSIONS: Commercially available lenses demonstrated the ability to release a clinically relevant amount of KF compared with conventional eye drops. The use of commercially available contact lenses as a KF delivery system in a daily wear scenario may be feasible.


Assuntos
Lentes de Contato , Sistemas de Liberação de Medicamentos , Cetotifeno/farmacocinética , Antialérgicos/farmacocinética , Humanos , Soluções Oftálmicas/farmacocinética , Espectrofotometria
12.
Clin Exp Optom ; 105(2): 149-156, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34407728

RESUMO

Healthcare in the twenty-first century has witnessed an increased use of prescription drugs. As a member of a patient's health care team, optometrists should be aware of the pharmaceuticals taken by patients and their potential ocular complications. This paper will discuss the most prescribed medications in Australia today and their effects on the visual system. The paper will review the agents used to treat six common systemic conditions, their frequency of use, mechanism of action, clinical indications, and potential ocular manifestations. Literature has documented both positive and negative associations of systemic medications on the eye's health. Many associations documented here have shown conflicting evidence, thus warranting further investigation. Based on the frequency and severity of the ocular manifestations in the literature, recommendations for clinical care are given. Being familiar with the most common ocular side effects associated with common systemic medications aids in the correct and timely diagnosis of ocular complications to prevent permanent sequelae.


Assuntos
Oftalmopatias , Optometristas , Optometria , Austrália , Oftalmopatias/diagnóstico , Oftalmopatias/tratamento farmacológico , Oftalmopatias/etiologia , Humanos , Preparações Farmacêuticas
13.
Clin Exp Optom ; 104(3): 308-314, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33689609

RESUMO

Adenoviral conjunctivitis is the most common cause of ocular viral infection in the world, but currently has no approved therapeutic treatments. The antiseptic povidone-iodine (PVP-I) has been used as an off-label treatment for the condition, but high-quality evidence for its use is limited. This paper aims to review the literature surrounding the use of PVP-I in the management of adenoviral conjunctivitis. Unfortunately, treatment regimens, inclusion criteria, outcome measures, and review periods vary widely between studies, making direct comparisons between outcomes difficult. The majority of studies investigate daily instillation of 0.4 to 2.0% PVP-I rather than one-time instillation of PVP-I as has been used anecdotally in practice. In addition, only one treatment arm investigates daily PVP-I alone, with no significant difference in the duration of disease or clinical outcome compared to placebo. All other treatment arms investigate PVP-I in combination with dexamethasone which generally improve outcomes. Tolerability of PVP-I is generally good for low concentrations <1.0%, but efficacy of treatment is generally reported to be concentration dependent. Future research should investigate the optimal concentration, dosing regimen and role of each agent in combination treatment and aim to use laboratory techniques to improve diagnosis and provide quantifiable outcomes.


Assuntos
Anti-Infecciosos Locais , Conjuntivite , Povidona-Iodo , Anti-Infecciosos Locais/uso terapêutico , Conjuntivite/tratamento farmacológico , Glucocorticoides , Humanos , Povidona-Iodo/uso terapêutico , Resultado do Tratamento
14.
Clin Exp Optom ; 104(3): 323-333, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33689618

RESUMO

Contact lenses are widely prescribed in clinical practice with multiple applications and advantages. However, contact lenses can be associated with various complications which range from innocuous to severe. Clinicians thus not only need to possess the ability to prescribe the most appropriate contact lenses for each individual patient but also be able to recognise and manage any associated complications. This review examines the existing literature on the management of corneal infiltrative events associated with soft contact lenses, including microbial keratitis, particularly in the context of practising in Australia. The definitions and diagnosis of corneal infiltrative events, as well as the current understanding of their aetiologies, will be explored. The various aspects of a successful management will be discussed, including the applications of therapeutic agents such as antimicrobial and anti-inflammatory agents, the role of microbiological investigations, and strategies to improve long-term prognosis. The currently available evidence supporting management options will be presented, highlighting the relative abundance of high-level evidence on management protocols, antimicrobial selection and treatment duration for microbial keratitis; and the relative paucity of studies and trials for sterile corneal infiltrative events, despite this condition being much more commonly encountered in clinical practice.


Assuntos
Lentes de Contato Hidrofílicas , Doenças da Córnea , Ceratite , Antibacterianos/uso terapêutico , Austrália , Humanos , Ceratite/diagnóstico , Ceratite/tratamento farmacológico
15.
Cont Lens Anterior Eye ; 44(2): 398-430, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33775384

RESUMO

Contact lenses in the future will likely have functions other than correction of refractive error. Lenses designed to control the development of myopia are already commercially available. Contact lenses as drug delivery devices and powered through advancements in nanotechnology will open up further opportunities for unique uses of contact lenses. This review examines the use, or potential use, of contact lenses aside from their role to correct refractive error. Contact lenses can be used to detect systemic and ocular surface diseases, treat and manage various ocular conditions and as devices that can correct presbyopia, control the development of myopia or be used for augmented vision. There is also discussion of new developments in contact lens packaging and storage cases. The use of contact lenses as devices to detect systemic disease has mostly focussed on detecting changes to glucose levels in tears for monitoring diabetic control. Glucose can be detected using changes in colour, fluorescence or generation of electric signals by embedded sensors such as boronic acid, concanavalin A or glucose oxidase. Contact lenses that have gained regulatory approval can measure changes in intraocular pressure to monitor glaucoma by measuring small changes in corneal shape. Challenges include integrating sensors into contact lenses and detecting the signals generated. Various techniques are used to optimise uptake and release of the drugs to the ocular surface to treat diseases such as dry eye, glaucoma, infection and allergy. Contact lenses that either mechanically or electronically change their shape are being investigated for the management of presbyopia. Contact lenses that slow the development of myopia are based upon incorporating concentric rings of plus power, peripheral optical zone(s) with add power or non-monotonic variations in power. Various forms of these lenses have shown a reduction in myopia in clinical trials and are available in various markets.


Assuntos
Lentes de Contato , Miopia , Presbiopia , Erros de Refração , Olho , Humanos , Refração Ocular , Erros de Refração/diagnóstico , Erros de Refração/terapia
16.
Clin Gastroenterol Hepatol ; 7(10): 1113-20, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19500693

RESUMO

BACKGROUND & AIMS: It is unclear whether surrogate end points reported in clinical trials correlate with long-term outcome of patients with chronic hepatitis B. METHODS: Patients with chronic hepatitis B who participated in any of 4 randomized controlled trials were followed prospectively for liver-related events (hepatocellular carcinoma, ascites, spontaneous bacterial peritonitis, variceal bleeding, liver transplantation, and death). Biochemical (normal ALT levels), virologic (levels of hepatitis B virus DNA below 10,000 copies/mL), and histologic (reduction of necroinflammation grading by 2 points or more with no increase in fibrosis staging) responses were evaluated at the end of each trial. RESULTS: One hundred ninety-five patients with adequate pretreatment and post-treatment liver biopsies (15 mm long and 6 portal tracts) were followed for 86 months (interquartile range, 77-98). Liver-related events occurred in 12 patients (6%). The risk of liver-related events was lower in patients with biochemical (hazard ratio, 0.21; 95% confidence interval, 0.068-0.68) and histologic (hazard ratio, 0.095; 95% confidence interval, 0.012-0.74) responses. Only 1 patient with a histologic response and 1 patient with an ALT level below Prati's cutoffs (30 IU/L in men and 19 IU/L in women) developed liver-related events. Fifteen of 25 patients (60%) with cirrhosis at baseline had regression of cirrhosis, and none of these patients died or developed liver-related events. In contrast, 3 of these patients still developed liver-related events, despite an initial virologic response, and 2 had virologic breakthrough. CONCLUSIONS: Biochemical and histologic responses, particularly regression of cirrhosis, in patients with chronic hepatitis B are associated with decreased liver-related complications.


Assuntos
Biomarcadores , Hepatite B Crônica/tratamento farmacológico , Adulto , Alanina Transaminase/sangue , DNA Viral/sangue , Proteínas de Drosophila , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento , Carga Viral
17.
Liver Int ; 29(1): 25-36, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18435714

RESUMO

BACKGROUND/AIMS: Celecoxib was used in the treatment of inflammation in patients with cirrhosis. However, data on the progression of liver fibrosis after treatment by celecoxib are not available. This study aims to elucidate the effects of celecoxib on cholestatic liver fibrosis in rats. METHODS: Rats underwent bile duct ligation (BDL) for 1 or 2 weeks to induce hepatic fibrosis. Celecoxib was introduced on day 1 after operation. The effects of celecoxib were assessed by comparison of the severity of hepatic fibrosis. RESULTS: Infiltration of inflammatory cells and proliferation of bile ducts was seen after 1 week of BDL and fibrosis was induced after 2 weeks. Reduced alanine aminotransferase (ALT) levels and blunted expression of inflammatory factors [tumour necrosis factor-alpha, interleukin (IL)-1beta and IL-6] were seen in the liver of BDL-treated rats that received celecoxib at week 1. Although celecoxib was sufficient in suppressing the cyclo-oxygenase (COX)-2 expression in the control organ (kidney), it failed to suppress the enhanced hepatic COX-2 expression. At week 2, celecoxib did not alter the ALT level, the severity of fibrosis and hepatic collagen contents. This was associated with unchanged alpha-smooth muscle actin protein expression and tissue inhibitor of metalloproteinase-2 (TIMP-2), matrix metalloproteinase (MMP)-2 and MMP-9 mRNA expressions in the liver. Celecoxib had no effect on the BDL-dependent increase in bilirubin levels at any time point. CONCLUSIONS: The present study provides morphological and molecular biological evidences for the role of celecoxib in cholestatic liver fibrosis. Celecoxib protects against hepatic inflammation in the early stage of BDL rats, but does not have an effect on liver fibrosis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cirrose Hepática/prevenção & controle , Fígado/metabolismo , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Alanina Transaminase/metabolismo , Animais , Ductos Biliares/cirurgia , Celecoxib , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ligadura , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Eye Contact Lens ; 35(5): 260-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19657281

RESUMO

OBJECTIVES: To investigate the uptake and release kinetics of the synthetic glucocorticoid anti-inflammatory drug dexamethasone into various conventional and silicone hydrogel contact lens materials. METHODS: Three conventional and six silicone hydrogel lenses were used in this study. A 0.1% dexamethasone solution was formulated and used to dope the various contact lens materials. The uptake and release of the drug was measured using a UV-visible light spectrophotometer at various time points during a period of 24 hr for each phase. RESULTS: Statistical analysis showed that all lenses took up a significant amount of dexamethasone. Alphafilcon A and lotrafilcon A showed the greatest uptake of dexamethasone, at 118 +/- 10 microg/lens and 102 +/- 11 microg/lens, respectively, and galyfilcon took up the least amount of drug at 34 +/- 6 microg/lens. The release of the drug from the lens materials was also statistically significant. The majority of the lenses released between 20 and 30 microg/lens, except for alphafilcon A and lotrafilcon A, which released a statistically different amount of drug when compared with the other lens materials. Alphafilcon A released 65 +/- 1.3 microg/lens, whereas lotrafilcon A slowly released only 11 +/- 0.2 microg/lens. CONCLUSIONS: Although most of the lenses released enough drug to have anti-inflammatory action, none of the materials released drug for a long enough period of time to be clinically useful as a drug delivery device.


Assuntos
Anti-Inflamatórios/farmacocinética , Lentes de Contato Hidrofílicas/classificação , Dexametasona/farmacocinética , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/normas , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Silicones , Espectrofotometria/métodos , Fatores de Tempo
19.
Drug Discov Today ; 24(8): 1427-1432, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30802601

RESUMO

The underlying mechanisms of dry eye are thought to be part of a vicious circle involving a hyperosmolarity-triggered inflammatory cascade, resulting in loss of goblet cells and glycocalyx mucin and observed corneal and conjunctival epithelial cell damage. This damage leads to increased tear film instability, further hyperosmolarity and hence perpetuating of a vicious circle. The aim of dry eye management is to restore the homeostasis of the tear film and break the perpetuation of this vicious circle. Despite the plethora of treatment options available, many of these are largely palliative, short-lived and require repeated instillations. Two emerging areas in dry eye therapy aim to promote tear secretion and to safely manage dry eye-associated inflammation and are the focus of this review.


Assuntos
Transporte Biológico/fisiologia , Síndromes do Olho Seco/metabolismo , Inflamação/metabolismo , Lágrimas/metabolismo , Animais , Células Epiteliais/metabolismo , Humanos
20.
Antivir Ther ; 13(8): 1029-37, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19195328

RESUMO

BACKGROUND: Early identification of non-responders to interferon-alpha and development of stopping rules are needed in patients with chronic hepatitis B to reduce treatment-related costs and morbidity. METHODS: In total, 47 patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B received pegylated interferon-alpha2b for 8 weeks, lamivudine plus pegylated interferon-alpha2b combination therapy for 24 weeks and lamivudine monotherapy for 28 weeks. Sustained virological response was defined as HBeAg seroconversion and hepatitis B virus (HBV) DNA < 10(5) copies/ml at the end of treatment and after 52 weeks of follow-up. The early HBV DNA data from the first 12 weeks of therapy were fitted by a viral kinetic model. RESULTS: Cutoff values for prediction of sustained virological response were defined as a rate of infected cell loss delta > or = 0.005 per day (negative predictive value [NPV] 100% and positive predictive value [PPV] 33.3%) and log values of the area under the mathematically predicted HBV DNA curve between baseline and week 12 of therapy < or = 8.9 log10 copies/ml x days (NPV 100% and PPV 50%). By the latter cutoff, 25/36 (69.4%) patients without sustained virological response could be identified after 12 weeks of therapy. CONCLUSIONS: In the present study, mathematical modelling of viral dynamics allowed prediction of sustained virological response after 12 weeks of therapy. Virodynamic predictors for sustained virological response should be further validated. The area under the mathematically predicted HBV DNA curve seems a promising candidate for potential cutoff values as it summarizes the influence of baseline HBV DNA and treatment effects.


Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Lamivudina/uso terapêutico , Adulto , Antivirais/administração & dosagem , DNA Viral/sangue , Feminino , Hepatite B Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Lamivudina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Polietilenoglicóis , Proteínas Recombinantes , Carga Viral
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