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1.
J. optom. (Internet) ; 16(1)January - March 2023. tab
Artigo em Inglês | IBECS | ID: ibc-214432

RESUMO

Purpose: The aim of this study was to analyse the postoperative corneal cross-linking results of corneal parameters and the ABCD grading system, depending on the cone location.MethodsThirty eyes of 25 patients with keratoconus (KC), who received the corneal cross-linking (CXL) treatment, were included in this study. The exclusion criteria were: patients under 18 years of age, corneal pachymetry less than 400 μm, corneal scarring, history of ocular trauma, history of ocular surgery, and corneal pathology other than KC. Patients were examined at the baseline visit, and followed-up at three, six, and twelve months after the CXL. All patients underwent visual acuity and Scheimpflug tomography at all visits. Progression parameters, keratometries, and ABCD grading were compared between the visits. Patients were classified into two groups: central and paracentral cones group (within the central 5 mm corneal zone) and peripheral cones group (outside the central 5 mm corneal zone), based on X-Y coordinates of maximal keratometry (Kmax).ResultsParameter A remained relatively stable throughout the follow-up period in both groups. Parameter B and parameter C showed a significant increase in both groups postoperatively. Parameter D showed stability at the 6-month post-CXL visit in the peripheral KC group, while the central and paracentral KC group showed improvement at the 12-month post-CXL visit.ConclusionThere was no significant difference in the postoperative response between different cone locations in the ABCD grading system, when classifying according to the Kmax, except an earlier recovery of the parameter D in peripherally located cones. (AU)


Assuntos
Humanos , Adolescente , Colágeno/uso terapêutico , Topografia da Córnea , Paquimetria Corneana , Reagentes de Ligações Cruzadas/uso terapêutico , Ceratocone/diagnóstico , Ceratocone/terapia , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Seguimentos , Fotoquimioterapia/métodos , Raios Ultravioleta
2.
PLoS One ; 18(1): e0279111, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36652495

RESUMO

OBJECTIVE: To investigate the effects of scleral collagen cross-linking (SXL) using riboflavin and ultraviolet A (UVA) light on the scleral thickness of different regions and expression of matrix metalloproteinase 2 (MMP-2) and membrane-type MMP-1 (MT1-MMP) in guinea pigs with lens-induced myopia. METHODS: Forty-eight 4-week-old guinea pigs were assigned to three groups (n = 16 per group): SXL group, lens-induced myopia (LIM) group, and control group. The sclera of the right eye of the guinea pig in the SXL group was surgically exposed, riboflavin was dropped on the treatment area for 10 minutes before the 30-minute UVA irradiation. The same surgical procedure was performed in the LIM group without UVA irradiation. The -10.00 D lenses were then placed on the right eyes of guinea pigs in the SXL and LIM groups for six weeks. The control group received no treatment. The left eyes were untreated in all groups. The ocular axial length (AXL) and refraction were measured at 4 weeks and 10 weeks of age. 10-week-old guinea pigs were sacrificed, and the right eyes were enucleated and evenly divided for preparation of hematoxylin and eosin (HE) stained sections, quantitative real-time polymerase chain reaction (qPCR) and western blotting. The scleral thickness of different regions was measured on HE stained sections. The temporal half of the sclera was harvested to measure the expression of MMP-2 and MT1-MMP by qPCR and western blotting. RESULTS: The AXL was significantly shorter, and the degree of myopic refraction was significantly lower in the SXL group than those in the LIM group at 10 weeks of age. The scleral thickness of the cross-linked area was significantly greater in the SXL group than that of the corresponding area in the LIM group, while the scleral thickness of the untreated nasal side was not significantly different between the SXL group and the LIM group. The expression of MMP-2 and MT1-MMP of the cross-linked sclera was significantly downregulated compared with that of the corresponding area in the LIM group. CONCLUSION: Riboflavin/UVA SXL could slow myopia progression and thicken the cross-linked sclera in guinea pigs, which might be related to the downregulation of MMP-2 and MT1-MMP expression during the scleral remodeling process.


Assuntos
Miopia , Esclera , Cobaias , Animais , Esclera/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Miopia/tratamento farmacológico , Miopia/metabolismo , Riboflavina/farmacologia , Riboflavina/metabolismo , Colágeno/metabolismo , Modelos Animais de Doenças
3.
PLoS One ; 18(1): e0278862, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662705

RESUMO

BACKGROUND: Monkeypox virus has recently emerged from endemic foci in Africa and, since October 20, 2022, more than 73,000 human infections have been reported by the CDC from over 100 countries that historically have not reported monkeypox cases. The detection of virus in skin lesions, blood, semen, and saliva of infected patients with monkeypox infections raises the potential for disease transmission via routes that have not been previously documented, including by blood and plasma transfusions. Methods for protecting the blood supply against the threats of newly emerging disease agents exist and include Pathogen Reduction Technologies (PRT) which utilize photochemical treatment processes to inactivate pathogens in blood while preserving the integrity of plasma and cellular components. Such methods have been employed broadly for over 15 years, but effectiveness of these methods under routine use conditions against monkeypox virus has not been reported. STUDY DESIGN AND METHODS: Monkeypox virus (strain USA_2003) was used to inoculate plasma and whole blood units that were then treated with riboflavin and UV light (Mirasol Pathogen Reduction Technology System, Terumo BCT, Lakewood, CO). The infectious titers of monkeypox virus in the samples before and after riboflavin + UV treatment were determined by plaque assay on Vero cells. RESULTS: The levels of spiked virus present in whole blood and plasma samples exceeded 103 infectious particles per dose, corresponding to greater than 105 DNA copies per mL. Treatment of whole blood and plasma units under standard operating procedures for the Mirasol PRT System resulted in complete inactivation of infectivity to the limits of detection. This is equivalent to a reduction of ≥ 2.86 +/- 0.73 log10 pfu/mL of infectivity in whole blood and ≥ 3.47 +/-0.19 log10 pfu/mL of infectivity in plasma under standard operating conditions for those products. CONCLUSION: Based on this data and corresponding studies on infectivity in patients with monkeypox infections, use of Mirasol PRT would be expected to significantly reduce the risk of transfusion transmission of monkeypox.


Assuntos
Varíola dos Macacos , Raios Ultravioleta , Animais , Chlorocebus aethiops , Humanos , Vírus da Varíola dos Macacos , Plaquetas , Células Vero , Riboflavina/farmacologia
4.
Indian J Ophthalmol ; 71(1): 75-79, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36588212

RESUMO

Purpose: To investigate the effects of riboflavin and/or ultraviolet-A (UV-A) irradiation on the cell viability of ex-vivo-cultured rat limbal stem cells (LSCs). Methods: LSCs of male Wistar rats (N = 12 eyes) were cultured, and immunofluorescence staining was performed to evaluate them. After characterization, these cells were assigned to four groups of control (C), a group that was exposed to UV-A radiation (UV), a group that was treated with riboflavin (R), and a group that cotreated with both UV-A and riboflavin (UV+R). To determine the cell viability of LSCs, these cells were subjected to MTT assay on days 1, 3, and 7 after exposure to UV-A and/or riboflavin. The duration of exposure to UV-A and riboflavin was similar to levels used during the conventional corneal collagen cross-linking procedure. Results: Compared with the viable cells in the control group, there was a significant decrease (P < 0.0001) in the number of LSCs in the UV group during all study days. In the R group, the level of viable LSCs was as same as the level of viable LSCs in the C group. Combined treatment with UV-A plus riboflavin significantly decreased the survival of LSCs on days 1 and 3 (P < 0.0001, P < 0.001, respectively) compared with the control group. Interestingly, in the UV+R group, the photosensitizing effect of riboflavin significantly decreased the cytotoxic effect of UV irradiation 7 days after exposure. Conclusion: These results suggest that the administered UV energy in the presence or absence of riboflavin can damage LSCs. Likewise, riboflavin could decrease the toxic effect of UVA on LSCs.


Assuntos
Fármacos Fotossensibilizantes , Riboflavina , Masculino , Animais , Ratos , Ratos Wistar , Riboflavina/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Raios Ultravioleta , Células-Tronco , Reagentes de Ligações Cruzadas/farmacologia , Córnea , Substância Própria
5.
BMC Ophthalmol ; 23(1): 37, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707782

RESUMO

BACKGROUND: To explore current eye care practice in keratoconus diagnosis and management in Kenya. METHODS: An online questionnaire was distributed to ophthalmic clinical officers (OCO) and optometrists. RESULTS: A total of 203 responses were received from 52 OCOs and 151 optometrists with a response rate of 24.4% and 53.5% respectively. The majority reported having access to retinoscopes (88.5%; p = 0.48) and slit lamps (76.7; p = 0.14). Few practitioners had access to a corneal topographer (13.5%; p = 0.08) and rigid contact lens (CL) fitting sets (OCOs 5.8%, optometrists 33.8%; p < 0.01). One-third did not feel that retinoscopy (38.7%; p = 0.21), slit lamp findings (30.3%; p = 0.10) and corneal topography (36.6%; p = 0.39) are important investigations in keratoconus diagnosis. Corneal topography was not recommended in two-thirds of patients (59.0%; p = 0.33) with vernal keratoconjunctivitis (VKC). The majority counselled against eye rubbing in mild (73.6%; p = 0.90) VKC, 52.9% in moderate (p = 0.40) and 43.6% in severe (p = 0.24) cases. The majority prescribed spectacles in mild (90.2%; p = 0.95), 29% (p = 0.97) in moderate and 1.9% (p = 0.05) in severe cases. When the binocular best corrected visual acuity (BCVA) with spectacles was ≤ 6/18, 76.9% of OCOs and 58.9% of optometrists referred for CLs (p = 0.02). When binocular BCVA with CLs dropped to ≤ 6/18, 83.7% (p = 0.18) referred to the ophthalmologist for surgical intervention. Few OCOs fitted rigid CLs (15.4% OCOs, 51.0% optometrists; p = 0.01), majority referred to optometrists (82.7% OCOs, 43.7% optometrists; p < 0.01). Progression was monitored in 70.1% (p = 0.11) of mild, 50.9% (p = 0.54) moderate and 25.3% (p = 0.31) advanced cases. Few OCOs (15.4%) performed corneal cross-linking (CXL). A few respondents (5.4%; p = 0.13) did not know when to refer keratoconus patients for CXL. Co-management with ophthalmologists was reported by 58.0% (p = 0.06) of respondents. CONCLUSION: The results of this study highlight the need to map services for keratoconus patients, review current curricula and continuous education priorities for mid-level ophthalmic workers, develop guidelines for the diagnosis and management of keratoconus and improve interdisciplinary collaboration.


Assuntos
Conjuntivite Alérgica , Ceratocone , Humanos , Ceratocone/diagnóstico , Ceratocone/terapia , Quênia , Acuidade Visual , Topografia da Córnea , Reagentes de Ligações Cruzadas , Fármacos Fotossensibilizantes , Riboflavina
6.
BMC Ophthalmol ; 23(1): 16, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627585

RESUMO

PURPOSE: Corneal collagen crosslinking (CXL) is an effective treatment for progressive keratoconus. Multiple CXL modalities are clinically available. The present study compared the 1 year outcomes of five types of CXL procedures for progressive keratoconus in a Chinese population using generalized estimating equations (GEE). METHODS: This retrospective study included 239 eyes in 171 patients with keratoconus who underwent CXL and were followed up for 1 year. Five CXL procedures were assessed, including Accelerated Transepithelial CXL, Iontophoresis CXL for 10 min, CXL plus phototherapeutic keratectomy (CXL-plus-PTK), High-Fluence Accelerated CXL, and Accelerated CXL. Patients treated with the Accelerated CXL procedure represented the reference group. Primary outcomes were visual acuity change, spherical equivalence, endothelial cell density, mean keratometry (Kmean), maximum keratometry (Kmax), minimum corneal thickness (MCT), and the ABCD Grading System, consisting of A (staging index for ARC; ARC = anterior radius of curvature), B (staging index for PRC, PRC = posterior radius of curvature), and C (staging index for MCT) values 1 year postoperatively compared to baseline. Secondary outcomes were corrected GEE comparisons from each procedure versus the Accelerated CXL group. RESULTS: The Accelerated Transepithelial CXL group had lower performance than the Accelerated CXL group according to Kmean and Kmax. The CXL-plus-PTK group performed significantly better than the reference group as reflected by Kmax (ß = -0.935, P = 0.03). However, the CXL-plus-PTK group did not perform as well for B and C, and the Iontophoresis CXL group performed better for C. CONCLUSIONS: The CXL-plus-PTK procedure was more effective than the Accelerated CXL procedure based on Kmax, and the Iontophoresis CXL procedure performed better on the C value based on the ABCD Grading System.


Assuntos
Ceratocone , Fotoquimioterapia , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Estudos Retrospectivos , Riboflavina/uso terapêutico , Seguimentos , Colágeno/uso terapêutico , Reagentes de Ligações Cruzadas/uso terapêutico , Raios Ultravioleta , Topografia da Córnea
7.
Anal Chem ; 95(2): 1671-1679, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36594807

RESUMO

Simple, selective, and sensitive detection of cerebral riboflavin is of great significance due to the vital roles of riboflavin in physiological and pathological processes. In the work, water-soluble photoluminescent adenosine-functionalized gold nanoclusters (Ade-AuNCs) are exploited as highly sensitive and selective receptors for cerebral riboflavin detection. The Ade-AuNCs are prepared under aqueous conditions by the one-step "synthesis-functionalization integration" strategy, using chloroauric acid as gold precursors and adenosine as outer-shell ligands. During the Ade-AuNCs synthesis process, adenosine and ascorbic acid are demonstrated to respectively serve as a stabilizer and a reductant, and citrate buffer plays multiple roles including a pH regulator, reductant, and complexing agent. The added riboflavin causes photoluminescence quenching of Ade-AuNCs, and the quenching photoluminescence is applied for well quantifying riboflavin in the range of 0.005-0.1 nM with a detection limit of 0.002 nM. The detailed analytical characterizations reveal that the photoluminescence quenching results from the static photoinduced electron transfer process from the surface functional Ade-AuNCs to riboflavin and the strong affinity between Ade-AuNCs and riboflavin. Moreover, the Ade-AuNC-based sensor exhibits a high selectivity for riboflavin over metal ions, anions, amino acids, and biological substances that possibly exist in the rat brain. Finally, by coupling the microdialysis technique, the proposed sensor is successfully applied to detect riboflavin in living rat brain microdialysates with a basal value of 13.1 ± 2.5 nM (n = 3), and the results are comparable well with those from a reference high-performance liquid chromatography method.


Assuntos
Nanopartículas Metálicas , Água , Ratos , Adenosina , Nanopartículas Metálicas/química , Espectrometria de Fluorescência/métodos , Ouro/química , Substâncias Redutoras , Riboflavina , Encéfalo
8.
Indian J Ophthalmol ; 71(1): 276-279, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36588250

RESUMO

The purpose of this article is to evaluate the effectiveness of collagen crosslinking of filtering blebs with 0.1% riboflavin stimulated with ultraviolet A radiation in a case of a thin-walled filtering bleb with leakage following an episode of late blebitis. The time to cessation of the bleb leakage was studied, as well as the intraocular pressure, the visual acuity, and the presence of adverse effects during 4 years of follow-up after treatment. A single session of crosslinking was effective in resolving the leakage of the filtering bleb. There were no adverse effects. The intraocular pressure and the visual acuity remained stable after 4 years of follow-up. Collagen crosslinking with 0.1% riboflavin stimulated with ultraviolet A radiation may prove to be a simple, painless, non-invasive, and repeatable treatment of the leaking bleb with the aim of strengthening the collagen fibers of the conjunctiva and avoiding more invasive surgical treatments.


Assuntos
Vesícula , Trabeculectomia , Humanos , Vesícula/cirurgia , Trabeculectomia/efeitos adversos , Pressão Intraocular , Túnica Conjuntiva/cirurgia , Riboflavina/uso terapêutico , Colágeno , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Reoperação
9.
Appl Environ Microbiol ; 89(1): e0131322, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36533923

RESUMO

Lactiplantibacillus plantarum is a lactic acid bacterium that is commonly found in the human gut and fermented food products. Despite its overwhelmingly fermentative metabolism, this microbe can perform extracellular electron transfer (EET) when provided with an exogenous quinone, 1,4-dihydroxy-2-naphthoic acid (DHNA), and riboflavin. However, the separate roles of DHNA and riboflavin in EET in L. plantarum have remained unclear. Here, we seek to understand the role of quinones and flavins in EET by monitoring iron and anode reduction in the presence and absence of these small molecules. We found that addition of either DHNA or riboflavin can support robust iron reduction, indicating electron transfer to extracellular iron occurs through both flavin-dependent and DHNA-dependent routes. Using genetic mutants of L. plantarum, we found that flavin-dependent iron reduction requires Ndh2 and EetA, while DHNA-dependent iron reduction largely relies on Ndh2 and PplA. In contrast to iron reduction, DHNA-containing medium supported more robust anode reduction than riboflavin-containing medium, suggesting electron transfer to an anode proceeds most efficiently through the DHNA-dependent pathway. Furthermore, we found that flavin-dependent anode reduction requires EetA, Ndh2, and PplA, while DHNA-dependent anode reduction requires Ndh2 and PplA. Taken together, we identify multiple EET routes utilized by L. plantarum and show that the EET route depends on access to environmental biomolecules and on the electron acceptor. This work expands our molecular-level understanding of EET in Gram-positive microbes and provides additional opportunities to manipulate EET for biotechnology. IMPORTANCE Lactic acid bacteria are named because of their nearly exclusive fermentative metabolism. Thus, the recent observation of EET activity-typically associated with anaerobic respiration-in this class of organisms has forced researchers to rethink the rules governing microbial metabolic strategies. Our identification of multiple routes for EET in L. plantarum that depend on two different redox active small molecules expands our understanding of how microbes metabolically adapt to different environments to gain an energetic edge and how these processes can be manipulated for biotechnological uses. Understanding the role of EET in lactic acid bacteria is of great importance due to the significance of lactic acid bacteria in agriculture, bioremediation, food production, and gut health. Furthermore, the maintenance of multiple EET routes speaks to the importance of this process to function under a variety of environmental conditions.


Assuntos
Flavinas , Quinonas , Humanos , Flavinas/metabolismo , Elétrons , Transporte de Elétrons , Riboflavina , Ferro
10.
Plant Cell Environ ; 46(3): 991-1003, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36578264

RESUMO

Iron (Fe) is an essential micronutrient, and deficiency in available Fe is one of the most important limiting factors for plant growth. In some species including Medicago truncatula, Fe deficiency results in accumulation of riboflavin, a response associated with Fe acquisition. However, how the plant's Fe status is integrated to tune riboflavin biosynthesis and how riboflavin levels affect Fe acquisition and utilization remains largely unexplored. We report that protein kinase CIPK12 regulates ferric reduction by accumulation of riboflavin and its derivatives in roots of M. truncatula via physiological and molecular characterization of its mutants and over-expressing materials. Mutations in CIPK12 enhance Fe accumulation and improve photosynthetic efficiency, whereas overexpression of CIPK12 shows the opposite phenotypes. The Calcineurin B-like proteins CBL3 and CBL8 interact with CIPK12, which negatively regulates the expression of genes encoding key enzymes in the riboflavin biosynthesis pathway. CIPK12 negatively regulates Fe acquisition by suppressing accumulation of riboflavin and its derivatives in roots, which in turn influences ferric reduction activity by riboflavin-dependent electron transport under Fe deficiency. Our findings uncover a new regulatory mechanism by which CIPK12 regulates riboflavin biosynthesis and Fe-deficiency responses in plants.


Assuntos
Deficiências de Ferro , Medicago truncatula , Medicago truncatula/metabolismo , Proteínas Quinases/metabolismo , Riboflavina/genética , Riboflavina/metabolismo , Ferro/metabolismo , Eletrólitos/metabolismo , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
J Agric Food Chem ; 70(51): 16347-16357, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36512435

RESUMO

A Box-Behnken experimental design was implemented in model wine (MW) to clarify the impact of copper, iron, and oxygen in the photo-degradation of riboflavin (RF) and methionine (Met) by means of response surface methodology (RSM). Analogous experiments were undertaken in MW containing caffeic acid or catechin. The results evidenced the impact of copper, iron, and oxygen in the photo-induced reaction between RF and Met. In particular, considering a number of volatile sulfur compounds (VSCs) that act as markers of light-struck taste (LST), both transition metals can favor VSC formation, which was shown for the first time for iron. Oxygen in combination can also affect the concentration of VSCs, and a lower content of VSCs was revealed in the presence of phenols, especially caffeic acid. The perception of "cabbage" sensory character indicative of LST can be related to the transition metals as well as to the different phenols, with potentially strong prevention by phenolic acids.


Assuntos
Metionina , Vinho , Vinho/análise , Cobre , Oxigênio , Compostos de Enxofre , Racemetionina , Ferro , Fenóis/análise , Riboflavina , Ácidos Cafeicos/farmacologia
12.
Sci Rep ; 12(1): 21640, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517529

RESUMO

Although probiotics are often indiscriminately prescribed, they are not equal and their effects on the host may profoundly differ. In vitro determination of the attributes of probiotics should be a primary concern and be performed even before clinical studies are designed. In fact, knowledge on the biological properties a microbe possesses is crucial for selecting the most suitable bacteriotherapy for each individual. Herein, nine strains (Bacillus clausii NR, OC, SIN, T, Bacillus coagulans ATCC 7050, Bifidobacterium breve DSM 16604, Limosilactobacillus reuteri DSM 17938, Lacticaseibacillus rhamnosus ATCC 53103, and Saccharomyces boulardii CNCM I-745) declared to be contained in six commercial formulations were tested for their ability to tolerate simulated intestinal conditions, adhere to mucins, and produce ß-galactosidase, antioxidant enzymes, riboflavin, and D-lactate. With the exception of B. breve, all microbes survived in simulated intestinal fluid. L. rhamnosus was unable to adhere to mucins and differences in mucin adhesion were evidenced for L. reuteri and S. boulardii depending on oxygen levels. All microorganisms produced antioxidant enzymes, but only B. clausii, B. coagulans, B. breve, and L. reuteri synthesize ß-galactosidase. Riboflavin secretion was observed for Bacillus species and L. rhamnosus, while D-lactate production was restricted to L. reuteri and L. rhamnosus. Our findings indicate that the analyzed strains possess different in vitro biological properties, thus highlighting the usefulness of in vitro tests as prelude for clinical research.


Assuntos
Probióticos , Antioxidantes , beta-Galactosidase , Mucinas , Lactatos , Riboflavina
13.
Transl Vis Sci Technol ; 11(12): 16, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580321

RESUMO

Purpose: To evaluate the impact of vitamin D (Vit D) supplementation on systemic biomarkers of collagen degradation, inflammation, oxidative stress, and copper metabolism in adolescent patients with keratoconus (KC). Methods: This was a prospective observational pilot study. Twenty patients (age range, 16-19 years) presenting KC and Vit D insufficiency (<30 ng/mL) were included. Vit D supplementation was prescribed by their general practitioner as per the standard of care. Patients were followed up for 12 months. At each visit, best spectacle-corrected visual acuity (BSCVA), maximal keratometry (Kmax), and thinnest corneal thickness (TCT) were evaluated. The primary outcome of the study was the proportion of patients with Kmax progression of less than 1 D throughout the 12-month follow-up time. Blood samples were collected at different time points to evaluate Vit D levels and systemic markers of collagen degradation, inflammation, oxidative stress, and copper metabolism by ELISA or RT-PCR. Results: Lower Vit D levels in the plasma were correlated with higher levels of systemic biomarkers of collagen degradation. Vit D supplementation increased the cell availability of copper. Moreover, stabilization of KC progression was found in 60% of patients (72% of eyes) after 12 months with Vit D supplementation. BSCVA, Kmax, and TCT rates remained stable during the observation period. Conclusions: Our findings support that Vit D administration could affect ocular and systemic biomarkers in KC and illuminate a possible mechanism that can be used to develop new treatment alternatives. Translational Relevance: Although KC therapy currently relies exclusively on surgical procedures, Vit D supplementation may offer a non-invasive and inexpensive alternative with minimal associated side effects.


Assuntos
Ceratocone , Fotoquimioterapia , Adolescente , Humanos , Adulto Jovem , Adulto , Ceratocone/tratamento farmacológico , Ceratocone/metabolismo , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Cobre/uso terapêutico , Acuidade Visual , Raios Ultravioleta , Riboflavina , Estudos Prospectivos , Seguimentos , Topografia da Córnea , Colágeno , Inflamação , Vitamina D/uso terapêutico , Suplementos Nutricionais
14.
Nutrients ; 14(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36500992

RESUMO

Cataracts are a prevalent ophthalmic disease worldwide, and research on the risk factors for cataracts occurrence is actively being conducted. This study aimed to investigate the relationship between nutrient intake and cataracts in the older adult population in Korea. We analyzed data from Korean adults over the age of 60 years (cataract: 2137, non-cataract: 3497) using the Korean National Health and Nutrition Examination Survey. We performed univariate simple and multiple logistic regressions, adjusting for socio-demographic, medical history, and lifestyle, to identify the associations between nutrient intake and cataracts. A higher intake of vitamin B1 in the male group was associated with a lower incidence of cataracts. A lower intake of polyunsaturated fatty acids and vitamin A, and a higher intake of vitamin B2 in the female group were associated with a higher incidence of cataracts. Our study demonstrated that polyunsaturated fatty acids, vitamin A, and vitamin B2 could affect the incidence of cataracts according to sex. The findings could be used to control nutrient intake for cataract prevention.


Assuntos
Catarata , Vitamina A , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estudos Transversais , Catarata/epidemiologia , Catarata/etiologia , Catarata/prevenção & controle , Riboflavina , República da Coreia/epidemiologia
15.
Proc Natl Acad Sci U S A ; 119(48): e2212436119, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36409903

RESUMO

Riboflavin is produced by most commensal bacteria in the human colon, where enterohemorrhagic Escherichia coli (EHEC) colonizes and causes diseases. Sensing environmental signals to site-specifically express the type-III secretion system (T3SS), which injects effectors into host cells leading to intestinal colonization and disease, is key to the pathogenesis of EHEC. Here, we reveal that EHEC O157:H7, a dominant EHEC serotype frequently associated with severe diseases, acquired a previously uncharacterized two-component regulatory system rbfSR, which senses microbiota-produced riboflavin to directly activate the expression of LEE genes encoding the T3SS in the colon. rbfSR is present in O157:H7 and O145:H28 but absent from other EHEC serotypes. The binding site of RbfR through which it regulates LEE gene expression was identified and is conserved in all EHEC serotypes and Citrobacter rodentium, a surrogate for EHEC in mice. Introducing rbfSR into C. rodentium enabled bacteria to sense microbiota-produced riboflavin in the mouse colon to increase the expression of LEE genes, causing increased disease severity in mice. Phylogenic analysis showed that the O55:H7 ancestor of O157:H7 obtained rbfSR which has been kept in O157:H7 since then. Thus, acquiring rbfSR represents an essential step in the evolution of the highly pathogenic O157:H7. The expression of LEE genes and cell attachment ability of other EHEC serotypes in the presence of riboflavin significantly increased when rbfSR was introduced into them, indicating that those serotypes are ready to use RbfSR to increase their pathogenicity. This may present a potential public health issue as horizontal gene transfer is frequent in enteric bacteria.


Assuntos
Escherichia coli Êntero-Hemorrágica , Escherichia coli O157 , Microbiota , Animais , Humanos , Camundongos , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli O157/genética , Riboflavina , Virulência/genética , Intestinos
16.
Cornea ; 41(12): 1471-1472, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36343164

RESUMO

ABSTRACT: Strong evidence suggests that corneal crosslinking is a safe procedure capable of stopping or slowing down the progression of keratoconus, avoiding visual loss associated with progression, and delaying or preventing the need for corneal transplantation. The progressive and chronic nature of the disease makes the option for prompt crosslinking upon keratoconus diagnosis in a pediatric patient valid.


Assuntos
Ceratocone , Fotoquimioterapia , Criança , Humanos , Ceratocone/diagnóstico , Ceratocone/tratamento farmacológico , Reagentes de Ligações Cruzadas/uso terapêutico , Fotoquimioterapia/métodos , Colágeno/uso terapêutico , Acuidade Visual , Progressão da Doença , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Raios Ultravioleta
18.
Sci Rep ; 12(1): 19346, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369258

RESUMO

Tartrazine is a synthetic yellowish dye considered one of the most common food colorants. Extensive usage of tartrazine in humans led to harmful health impacts. To investigate the impact of tartrazine administration on the cerebellum and to assess the potential role of riboflavin co-administration in the adult male albino rat. Four groups of adult albino rats were included in this study. Group I was supplied with distilled water. Group II was supplied tartrazine orally at a dose of 7.5 mg/kg BW dissolved in distilled water. Group III was supplied with tartrazine at the same previously mentioned dose and riboflavin orally at a dose of 25 mg/kg BW dissolved in distilled water. Group IV was supplied with riboflavin at the same previously mentioned dose. The study was conducted for 30 days then rats were sacrificed, weighted and the cerebella extracted and handled for light, ultrastructural and immunohistochemical evaluation. It was found with tartrazine treatment focal areas of Purkinje cell loss leaving empty spaces, a broad spread of neuronal affection to the degree of the disappearance of some of the granular cells, reduced the thickness of the molecular and granular layers, and strong positive GFAP immunoreactions. With riboflavin coadministration restored continuous Purkinje layer with normal appeared Purkinje cells, but some cells were still shrunken and vacuolated as well as the molecular and granular cell layers appeared normal. Tartrazine had deleterious effects on the cerebellar cytoarchitecture, and riboflavin co-administration alleviated these neurotoxic effects.


Assuntos
Corantes de Alimentos , Tartrazina , Masculino , Ratos , Córtex Cerebelar , Corantes de Alimentos/toxicidade , Riboflavina/farmacologia , Tartrazina/toxicidade
19.
Asia Pac J Ophthalmol (Phila) ; 11(6): 514-520, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36417675

RESUMO

PURPOSE: This study evaluated the biomechanical E-staging in progressive keratoconus (KC) corneas before and after epithelium-off accelerated corneal cross-linking (CXL, 9 mW/cm2, 10 min, 5.4 J/cm2). DESIGN: German university-based retrospective longitudinal cohort study. METHODS: The biomechanical E-staging for ectatic corneal diseases was applied retrospectively on 49 progressive KC corneas of 41 patients who underwent CXL. Main outcome parameters included the Corvis Biomechanical Factor (CBiF, the linearized Corvis Biomechanical Index), the biomechanical E-staging (E1 to E4 result of dividing the CBiF value range into 5 groups), maximal anterior keratometry (Kmax), anterior radius of curvature (ARC), and thinnest corneal thickness (TCT). They were evaluated at 2.1±2.0 months preoperatively (n=49 corneas, 41 patients) and postoperatively after 5.4±1.4, 11.3±1.8, and 23.4±1.6 months. RESULTS: The CBiF decreased (5.1±0.5 | 5.0±0.5, P=0.0338) and the E-staging increased significantly (2.4±0.9 | 2.6±0.8, P=0.0035) from preoperatively to the first postoperative follow-up. The difference was not significant after 11 months and there were same values after 23 months. Kmax, ARC, and TCT slightly decreased (Kmax: 56.9±6.3, 54.3±5.1, 56.2±6.6, 54.0±5.2; ARC: 49.8±3.5, 48.9±3.2, 50.8±5.6, 49.0±3.7; TCT: 470±34, 454±36, 459±35, 466±39; preoperatively and 5, 11, and 23 months postoperatively). A postoperatively decreased TCT was associated with an increased E-stage, whereas an equal or increased TCT measurement after CXL was associated with equal or lower E-staging results. CONCLUSIONS: The biomechanical E-staging in KC corneas is influenced by TCT measurements and increases within the first postoperative months after CXL. On the long term, it indicates a postoperative KC stabilization, with comparable E-values to preoperatively at 11 and 23 months after CXL.


Assuntos
Ceratocone , Fotoquimioterapia , Humanos , Ceratocone/tratamento farmacológico , Ceratocone/cirurgia , Estudos Retrospectivos , Topografia da Córnea , Riboflavina/uso terapêutico , Estudos Longitudinais , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Colágeno/uso terapêutico , Acuidade Visual , Raios Ultravioleta , Córnea/cirurgia
20.
Food Funct ; 13(23): 12246-12257, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36342407

RESUMO

Vitamin B2 is essential for DNA methylation, stability and repair, which may influence the development and pathogenesis of several cancers. However, data regarding the associations of circulating vitamin B2 with colorectal cancer risk are limited. The purpose of this study was to investigate the associations between serum vitamin B2 and colorectal cancer risk, particularly among participants with different serum levels of vitamin B6 or folate. A hospital-based case-control study, including 1009 colorectal cancer cases and 1182 controls matched by age and sex, was conducted in Guangdong Province, China. Vitamin B2 including riboflavin and flavin mononucleotide (FMN), the vitamin B6 indicator pyridoxal-5'-phosphate (PLP) and folate in serum samples were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry. Vitamin B2 sum was calculated as the sum of riboflavin plus FMN. A significant inverse association was observed between serum FMN, but not serum riboflavin or vitamin B2 sum, and colorectal cancer risk. The adjusted odds ratio (OR) and 95% confidence interval (95% CI) of serum FMN, by comparing the highest with the lowest quartile, was 0.63 (0.46-0.85, Ptrend = 0.001). Stratified analysis by serum PLP and folate levels indicated that serum FMN was inversely associated with colorectal cancer risk among participants with lower serum PLP or higher folate levels. This study added supporting data to the limited evidence that vitamin B2 could play a preventive role in colorectal carcinogenesis among the Chinese population, primarily by FMN. Individuals with a lower PLP level or an adequate folate level could be more sensitive to the protective role of vitamin B2.


Assuntos
Neoplasias Colorretais , Mononucleotídeo de Flavina , Humanos , Estudos de Casos e Controles , Vitamina B 6 , Riboflavina , Ácido Fólico , Neoplasias Colorretais/genética , Vitaminas
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