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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120268, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34450573

RESUMO

The computational simulation of the photoelectron spectrum of active form of vitamin B2 is reported in the gas phase. In this work, we determine relative stability of eight riboflavin conformers by conformational search first with molecular mechanics AMMP potential in VEGA software at 553 K. Relative abundance of conformers was deduced from Boltzmann population weighting method (BPW). The three most stable conformers were then selected for computing valence, vertical ionization energies. We used high-level Equation-of-Motion Coupled-Cluster (EOM-IP-CCSD) method to obtain valence ionization energies (IP). In order to characterize the nature of ionization processes pertaining to different spectral bands, natural bonding orbital (NBO) method and molecular electrostatic potentials (MEP) were used to obtain orbital electron densities. The influence of the electronic structure of riboflavin on its biological activity is manifested via reduction of ionization energies of outermost orbitals which makes electron densities of these orbitals more readily available to participate in ligand-receptor bonding.


Assuntos
Eletrônica , Riboflavina , Simulação por Computador , Conformação Molecular
2.
J Refract Surg ; 37(11): 741-745, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34756139

RESUMO

PURPOSE: To compare standard epithelium-off corneal cross-linking (standard Epi-Off CXL) to corneal cross-linking with an epithelial flap (Epi-Flap CXL). METHODS: Patients who had undergone sequential bilateral CXL for progressive keratoconus were included in this comparative interventional case series. One eye was treated with the Epi-Off CXL technique and the fellow eye with the Epi-Flap CXL technique. Postoperative pain was measured using the Verbal Rating Scale and corneal densitometry using a Scheimpflug camera. Sex, age, corrected distance visual acuity, keratometry, and corneal thickness were also recorded. RESULTS: Twenty-four eyes of 12 patients with keratoconus with a mean age of 27.15 ± 5.15 years were included. The Verbal Rating Scale scores were significantly lower in patients who had Epi-Flap CXL on the first (1.00 [interquartile range (IQR): 0.00 to 1.00] vs 3.00 [IQR: 3.00 to 3.75], P = .01) and third (0.00 [IQR: 0.00 to 1.00] vs 1.00 [IQR: 0.00 to 1.00], P = .01) postoperative day compared to the Epi-Off CXL group. No pain was observed in both groups after the third day. After 12 months, the Epi-Flap CXL group showed significantly less anterior corneal haze (measured as corneal densitometry) compared to the patients treated with Epi-Off CXL (P = .01). Both groups demonstrated stability of keratometry and corneal thickness at 12 months after CXL (P < .01). CONCLUSIONS: Epi-Flap CXL is associated with less postoperative pain and anterior stromal haze in patients undergoing CXL for progressive keratoconus with no loss of efficacy. [J Refract Surg. 2021;37(11):741-745.].


Assuntos
Ceratocone , Fotoquimioterapia , Adulto , Colágeno/uso terapêutico , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Raios Ultravioleta , Adulto Jovem
3.
Vestn Oftalmol ; 137(5. Vyp. 2): 224-230, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34669331

RESUMO

PURPOSE: To study the condition of precorneal tear film in keratoconus patients after corneal collagen cross-linking (CXL). MATERIAL AND METHODS: The study enrolled 24 patients (30 eyes) with stages I-III progressive keratoconus. All study patients underwent standard (Dresden) protocol CXL. Patients were examined before the surgery and 1 week, 1 month, and 3 months postoperatively. The condition of precorneal tear film was evaluated based on the results of Norn test (the tear film break-up time), Schirmer test, Jones test, optical coherence tomography based lacrimal meniscometry, and improved tearscopy. RESULTS: One month after CXL, patients with keratoconus experienced transient changes in the precorneal tear film condition - the tear film break-up time was reduced, the tear secretion was elevated, the lacrimal meniscus biometry parameters were increased, and the thickness of the tear film lipid layer was decreased. CONCLUSION: Corneal changes resulting from CXL lead to transient disorders of the mucin and lipid layers of the precorneal tear film, which requires adequate tear substitute therapy in the postoperative period.


Assuntos
Ceratocone , Fotoquimioterapia , Colágeno , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Humanos , Ceratocone/diagnóstico , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes , Riboflavina , Raios Ultravioleta
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(5): 869-876, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34713654

RESUMO

The effect of parasitic ions on the results of ultraviolet A (UVA) cross-linking in iontophoresis was still not clear. In this work, the porcine sclera was cross-linked by riboflavin lactate Ringer's solution (group A) and riboflavin normal saline (group B) in vitro, respectively. The concentration of parasitic ions in the solution was calculated. In addition, the average fluorescence intensity, penetration depth and concentration after the introduction of riboflavin and the mechanical properties of cross-linked sclera tissue were measured. The ranges of diffusion coefficient of the two solutions were also calculated, respectively. The results showed that more kinds of parasitic ions were detected in group A compared with group B, while the average fluorescence intensity, penetration depth and concentration of riboflavin and scleral elastic modulus in group B were significantly higher than those in group A when the penetration time was 10 minutes. Besides, the diffusion coefficient of riboflavin in group B was about 1.5 times larger than that in group A. The results suggested that the species of parasitic ions has a great impact on the permeability of riboflavin, and affects the mechanical properties of cross-linked sclera. The above results could provide a reference for improving the efficiency of riboflavin introduction and optimizing the formula of riboflavin in iontophoresis scleral cross-linking.


Assuntos
Iontoforese , Esclera , Animais , Colágeno , Reagentes para Ligações Cruzadas , Íons , Permeabilidade , Fármacos Fotossensibilizantes/farmacologia , Riboflavina , Suínos , Raios Ultravioleta
5.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 50(4): 454-462, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34704421

RESUMO

To investigate the incidence rate, clinical and gene mutation characteristics of multiple acyl-CoA dehydrogenase deficiency (MADD) in newborns in Zhejiang province. A total of 3 896 789 newborns were screened for MADD using tandem mass spectrometry in Zhejiang Neonatal Screening Center during January 2009 and December 2020. Patients of MADD were confirmed by urine organic acid and electron transferring flavoprotein (or electron transferring flavoprotein dehydrogenase () gene detection. MADD patients were given diet and life management, supplemented with L-carnitine, riboflavin and coenzyme Q 10 treatment, and their growth and intellectual development were evaluated during the followed up.Thirteen patients with MADD were diagnosed, with an incidence of 1/299 753. One patient was type Ⅱ, and the rest were type Ⅲ. Patients were followed up for 1 case died, 4 cases had acute metabolic disorders with hypoglycemia as the main manifestation due to infection, 1 case had hypotonia, and the rest 7 cases developed well. Patients had raised levels of C4-C18:1 acylcarnitines in the initial screening. Thirteen children were genetically tested, 1 case with compound heterozygous mutation in the gene, 1 case with homozygous mutation in the gene, 1 case with compound heterozygous mutation in the gene, 8 cases with compound heterozygous mutation and 1 case with homozygous mutation in the gene, 1 case that only 1 locus of gene was detected. The c.250G>A was the hotspot mutation in this study.The clinical manifestations of MADD are highly heterogeneous. The neonatal-onset form is serious, and late onset form usually has no obvious clinical symptoms. C4-C18:1 acylcarnitines usually increased in the initial screening, and the hotspot gene mutation is c.250G>A.


Assuntos
Deficiência Múltipla de Acil Coenzima A Desidrogenase , Criança , Seguimentos , Humanos , Recém-Nascido , Deficiência Múltipla de Acil Coenzima A Desidrogenase/diagnóstico , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Mutação , Triagem Neonatal , Riboflavina
6.
J Agric Food Chem ; 69(41): 12241-12249, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623820

RESUMO

Riboflavin is widely used as a food additive. Here, multiple strategies were used to increase riboflavin production in Escherichia coli LS31T. First, purR deletion and co-overexpression of fbp, purF, prs, gmk, and ndk genes resulted in an increase of 18.6% in riboflavin titer (reaching 729.7 mg/L). Second, optimization of reduced nicotinamide adenine dinucleotide phosphate/nicotinamide adenine dinucleotide ratio and respiratory chain activity in LS31T increased the titer up to 1020.2 mg/L. Third, the expression level of the guaC gene in LS31T was downregulated by ribosome binding site replacement, and the riboflavin production was increased by 10.6% to 658.5 mg/L. Then, all the favorable modifications were integrated together, and the resulting strain LS72T produced 1339 mg/L of riboflavin. Moreover, the riboflavin titer of LS72T reached 21 g/L in fed-batch cultivation, with a yield of 110 mg riboflavin/g glucose. To our knowledge, both the riboflavin titer and yield obtained in fed-batch fermentation are the highest ones among all the rationally engineered strains.


Assuntos
Escherichia coli , Riboflavina , Escherichia coli/genética , Fermentação , Glucose , Engenharia Metabólica
7.
J Refract Surg ; 37(10): 700-706, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34661479

RESUMO

PURPOSE: To assess corneal stability and corrected distance visual acuity (CDVA) 3, 6, and 12 months following corneal cross-linking (CXL) using the ABCD keratoconus staging system. METHODS: This prospective longitudinal study included 31 eyes with keratoconus receiving CXL based on the standard Dresden protocol. CDVA, refraction, and Scheimpflug tomography with the Pentacam HR (Oculus Optikgeräte GmbH) were evaluated before and after surgery. Geometric and functional changes were assessed using the actual values and staging of each element of the ABCD keratoconus staging system. A, B, C, and D refer to the anterior and posterior radii of curvature in a 3-mm zone centered on the cor-neal thinnest point, minimum corneal thickness, and CDVA, respectively. RESULTS: There were no significant changes in the actual values of anterior radius of curvature (P = .497) and CDVA (P = .082), whereas posterior radius of curvature (P = .007) and corneal thinnest point (P < .001) showed significant changes statistically. Pairwise comparison showed only a statistically significant steepening in posterior radius of curvature at 3 months after CXL compared to the preoperative radius (P = .002) and a significant decrease in corneal thinnest point at 3 (P < .001) and 6 (P = .028) months after CXL compared to baseline assessment. Staging of each element of the ABCD keratoconus staging system indicated no change between baseline and 3, 6, and 12 months after CXL. CONCLUSIONS: The geometric and functional parameters included in the ABCD keratoconus staging system showed stability of corneal status and CDVA 1 year after CXL. [J Refract Surg. 2021;37(10):700-706.].


Assuntos
Ceratocone , Fotoquimioterapia , Colágeno/uso terapêutico , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Humanos , Ceratocone/tratamento farmacológico , Estudos Longitudinais , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Prospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta , Acuidade Visual
8.
J Biomed Nanotechnol ; 17(9): 1866-1873, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688332

RESUMO

The present investigation undertakes the formulation of nanoparticulate suspension of Riboflavin to treat keratoconus disease by applying it to the infected mice corneas. The nanoparticles of Riboflavin were prepared using single solvent evaporation method and later formulated as suspension using continuous probe sonication method. Then, both riboflavin nanoparticles and suspension were evaluated for various parameters. The nanoparticles showed smooth and spherical surface with in vitro drug release up to 77.89%. The drug content was found to be 97.23%-98.89%. The suspension was found to be visually clear with pH ranging from 6 to 7. The drug entrapment was found to be from 76.37% to 97.34%. Since there was no hemolytic activity, this formulation was suitable for ophthalmic administration. The Draize test confirmed the non-irritant, non-itchy nature of formulation. The prepared formulations, such as nanoparticulate gel and suspension, were found to be significantly efficacious in experimental animals.


Assuntos
Ceratocone , Nanopartículas , Administração Oftálmica , Animais , Liberação Controlada de Fármacos , Ceratocone/tratamento farmacológico , Camundongos , Tamanho da Partícula , Coelhos , Riboflavina
9.
Molecules ; 26(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34641554

RESUMO

The application of electrospray ionisation mass spectrometry (ESI-MS) as a direct method for detecting reactive intermediates is a technique of developing importance in the routine monitoring of solution-phase reaction pathways. Here, we utilise a novel on-line photolysis ESI-MS approach to detect the photoproducts of riboflavin in aqueous solution under mildly alkaline conditions. Riboflavin is a constituent of many food products, so its breakdown processes are of wide interest. Our on-line photolysis setup allows for solution-phase photolysis to occur within a syringe using UVA LEDs, immediately prior to being introduced into the mass spectrometer via ESI. Gas-phase photofragmentation studies via laser-interfaced mass spectrometry of deprotonated riboflavin, [RF - H]-, the dominant solution-phase species under the conditions of our study, are presented alongside the solution-phase photolysis. The results obtained illustrate the extent to which gas-phase photolysis methods can inform our understanding of the corresponding solution-phase photochemistry. We determine that the solution-phase photofragmentation observed for [RF - H]- closely mirrors the gas-phase photochemistry, with the dominant m/z 241 condensed-phase photoproduct also being observed in gas-phase photodissociation. Further gas-phase photoproducts are observed at m/z 255, 212, and 145. The value of exploring both the gas- and solution-phase photochemistry to characterise photochemical reactions is discussed.


Assuntos
Fotólise , Riboflavina/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Gases/química , Transição de Fase , Fotoquímica
10.
Lab Chip ; 21(21): 4071-4080, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34618882

RESUMO

Microbial cells represent a standard production host for various important biotechnological products. Production yields can be increased by optimising strains and growth conditions and understanding deviations in production rates over time or within the microbial population. We introduce here microfluidic cultivation chambers for highly parallel studies on microbial cultures, enabling continuous biosynthesis monitoring of the industrially relevant product by Escherichia coli cells. The growth chambers are defined by ring-valves that encapsulate a volume of 200 pL when activated. Bacterial cells, labelled with magnetic beads, are inoculated in a small magnetic trap, positioned in the centre of each chamber. Afterwards, the ring-valves are partially activated, allowing for exchange reagents, such as the addition of fresh media or specific inducers of biosynthesis, while the bacterial cells and their progeny are maintained inside. On this platform, we monitor the production of riboflavin (vitamin B2). We used different variants of a riboflavin-overproducing bacterial strain with different riboflavin production levels and could distinguish them on the level of individual micro-colonies. In addition, we could also observe differences in the bacterial morphology with respect to the production. The presented platform represents a flexible microfluidic tool for further studies of microbial cell factories.


Assuntos
Escherichia coli , Microfluídica , Riboflavina/biossíntese , Vitaminas/biossíntese , Meios de Cultura , Escherichia coli/genética , Microbiologia Industrial
11.
J Refract Surg ; 37(9): 631-635, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506235

RESUMO

PURPOSE: To evaluate corneal stiffening in porcine eyes induced by corneal cross-linking (CXL) using riboflavin dissolved in either aqueous dextran or hydroxypropyl methylcellulose (HPMC) solution. METHODS: Fifty-one porcine corneas were divided into three groups of 17 each. After deepithelialization, the first (Dresden) group was treated for 30 minutes with 0.1% riboflavin (riboflavin-5-monophosphate in 0.9% NaCl) dissolved in hypertonic 20% dextran and the second (HPMC) group for 30 minutes with isotonic solution containing 0.1% riboflavin and 1.1% HPMC. Thereafter, corneas of both groups were irradiated using 5.4 J/cm2 (irradiance of 9 mW/cm2 for 10 minutes; 10*9). After CXL, all corneas were kept in an isotonic 16% dextran bath for 2 hours to obtain an equal hydration state. The third group served as the control group. Stress-strain measurements were performed on 5-mm-wide strips. Corneal thickness was monitored throughout the entire course of the experiments. RESULTS: The required stress for a 10% strain was increased by 83% in the Dresden group and 35% in the HPMC group compared to the control group. Resultant Young's modulus (at 10% strain) was 2.53 ± 0.73, 1.87 ± 0.50, and 1.47 ± 0.44 Pa for the Dresden, HPMC, and control groups, respectively. The differences between the Dresden and HPMC groups (P = .006), the Dresden and control groups (P < .001), and the HPMC and control groups (P = .014) were statistically significant. Pachymetry measurements showed a significantly increased corneal thickness after application of HPMC compared with the Dresden group (P = .002) and control group (P = .041). CONCLUSIONS: The biomechanical stiffening of the cornea by CXL can be achieved using dextran- and HPMC-based riboflavin solutions in porcine corneas with an application time of 30 minutes. Dextran-based riboflavin solutions seem to induce a slightly stronger biomechanical response in this setting. HPMC solutions induce less thinning than dextran solutions. [J Refract Surg. 2021;37(9):631-635.].


Assuntos
Substância Própria , Dextranos , Animais , Fenômenos Biomecânicos , Colágeno , Córnea , Reagentes para Ligações Cruzadas , Derivados da Hipromelose , Fármacos Fotossensibilizantes , Riboflavina/farmacologia , Suínos , Raios Ultravioleta
12.
J Refract Surg ; 37(9): 623-630, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506244

RESUMO

PURPOSE: To compare the clinical and tomographic properties of adult patients with keratoconus treated with accelerated corneal cross-linking (A-CXL) versus accelerated contact lens-assisted corneal cross-linking (A-CACXL). METHODS: Patients who underwent A-CXL and A-CACXL due to progressive keratoconus were enrolled from January 2015 to January 2018 in this retrospective case-control study. The treatment group (minimum corneal thickness of less than 400 µm after epithelium removal; 30 patients, 30 eyes) was treated with A-CACXL; the control group (minimum corneal thickness of 400 µm or greater, 32 patients, 32 eyes) was treated with A-CXL. Assessments occurred before treatment and 12 months postoperatively. Demographic, clinical, and tomographic data were obtained from outpatient clinic reports. RESULTS: Significant improvement in visual acuity was evident at 12-month follow-up for the control group in uncorrected distance visual acuity (0.62 ± 0.42 vs 0.43 ± 0.31 logMAR, P = .01) and the treatment group in corrected distance visual acuity (0.51 ± 0.30 vs 0.40 ± 0.49 logMAR, P = .03). Progression of keratoconus was halted at similar rates for both groups (76.7% treatment, 84.4% control, P = .21). Mean minimum corneal thickness showed minor but significant thinning at the 12-month follow-up visit compared to baseline (control group = 463 ± 31 vs 450 ± 35 µm, P > .01; treatment group = 398 ± 32 vs 388 ± 41 µm, P = .02). CONCLUSIONS: A-CACXL halted keratoconus progression in 76.7% of eyes and achieved regression in 33.3% of eyes, with rates comparable to A-CXL. Visual outcomes improved for both groups, with similar keratometry changes. A-CACXL is an effective and safe option for patients with keratoconus and thin corneas, with results similar to A-CXL treatment in patients with a minimum corneal thickness of 400 µm or greater. [J Refract Surg. 2021;37(9):623-630.].


Assuntos
Lentes de Contato , Ceratocone , Fotoquimioterapia , Adulto , Estudos de Casos e Controles , Colágeno/uso terapêutico , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Seguimentos , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta
13.
Cesk Slov Oftalmol ; 77(4): 184-189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34507494

RESUMO

AIM: To evaluate the effect of crosslinking (CXL) therapy on the change in the quality of visual acuity and the change in the topographic properties of the cornea - curvature, pachymetry, and change of astigmatism, coma abberation and CLMIaa (Cone Localisation and Magnitude Index). METHODS: A retrospective analytical study included 29 eyes of 24 patients who had progressed in the last 12 months and were suitable candidates for CXL surgery. The monitored parameters were the steepest, flatest and mean anterior instantaneous curvature (AICS, AICF, AICM) and the steepest, flatest and mean posterior instantaneous curvature (PICS, PICF, PICM) of the cornea, corneal thickness in the centre of the cornea (PACHC) and in the thinnest point of the cornea (PACHT), corneal astigmatism (ASTIG). coma (COMA), Cone Localization and Magnitude Index (CLMIaa) and uncorrected distance visual acuity (UDVA) with corrected distance visual acuity (CDVA). Data were analysed before surgery and 12 months after surgery. The AIC, COMA, CLMIaa and ASTIG parameters were analysed by paired t test. As the parameters of UDVA, CDVA, PIC and PACH did not meet the conditions of normal distribution, the Wilcoxon test was used to investigate the change in these parameters after CXL. RESULTS: Twelve months after the procedure, we recorded an improvement in UDVA (p = 0.371) and CDVA (p = 0.825), an increase in PICS, PICF and PICM (p = 0.902; p = 0.87 and p = 0.555), a decrease in PACHCC (p = 0.294) and a decrease in CLMIaa (p = 0.113) that did not reach statistical significance. The decrease in PACHT (p = 0.027), decrease in COMA (p = 0.037) and decrease in anterior corneal curvature of AICS, AICF and AICM were statistically significant (p = 0.019; p = 0.010 and p = 0.005). The decrease in the value of astigmatism did not show statistical significance, as p = 0.297. CONCLUSION: CXL corneal therapy has been shown to be an effective method to stabilize the cornea in progressive keratoconus, and to improve the higher order of coma. This contributes to the possible improvement of UDVA and CDVA.


Assuntos
Ceratocone , Colágeno , Córnea , Substância Própria , Topografia da Córnea , Reagentes para Ligações Cruzadas , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Acuidade Visual
14.
Appl Microbiol Biotechnol ; 105(20): 7813-7823, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34559286

RESUMO

This study focuses on sirtuins, which catalyze the reaction of NAD+-dependent protein deacetylase, for riboflavin production in A. gossypii. Nicotinamide, a known inhibitor of sirtuin, made the color of A. gossypii colonies appear a deeper yellow at 5 mM. A. gossypii has 4 sirtuin genes (AgHST1, AgHST2, AgHST3, AgHST4) and these were disrupted to investigate the role of sirtuins in riboflavin production in A. gossypii. AgHST1∆, AgHST3∆, and AgHST4∆ strains were obtained, but AgHST2∆ was not. The AgHST1∆ and AgHST3∆ strains produced approximately 4.3- and 2.9-fold higher amounts of riboflavin than the WT strain. The AgHST3∆ strain showed a lower human sirtuin 6 (SIRT6)-like activity than the WT strain and only in the AgHST3∆ strain was a higher amount of acetylation of histone H3 K9 and K56 (H3K9ac and H3K56ac) observed compared to the WT strain. These results indicate that AgHst3 is SIRT6-like sirtuin in A. gossypii and the activity has an influence on the riboflavin production in A. gossypii. In the presence of 5 mM hydroxyurea and 50 µM camptothecin, which causes DNA damage, especially double-strand DNA breaks, the color of the WT strain colonies turned a deeper yellow. Additionally, hydroxyurea significantly led to the production of approximately 1.5 higher amounts of riboflavin and camptothecin also enhanced the riboflavin production even through the significant difference was not detected. Camptothecin tended to increase the amount of H3K56ac, but the amount of H3K56ac was not increased by hydroxyurea treatment. This study revealed that AgHst1 and AgHst3 are involved in the riboflavin production in A. gossypii through NAD metabolism and the acetylation of H3, respectively. This new finding is a step toward clarifying the role of sirtuins in riboflavin over-production by A. gossypii.Key points• Nicotinamide enhanced the riboflavin production in Ashbya gossypii.• Disruption of AgHST1 or AgHST3 gene also enhanced the riboflavin production in Ashbya gossypii.• Acetylation of H3K56 led to the enhancement of the riboflavin production in Ashbya gossypii.


Assuntos
Eremothecium , Riboflavina/biossíntese , Sirtuínas , Dano ao DNA , Eremothecium/genética , Sirtuínas/genética
15.
BMC Ophthalmol ; 21(1): 317, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465309

RESUMO

INTRODUCTION: We present seven cases of infectious keratitis after corneal crosslinking (CXL) to attenuate keratoconus progression. METHODS: Of 524 consecutive patients who underwent CXL, 7 cases (4 males and 3 females; 21.5 ± 7.1 years) developed postoperative infectious keratitis were retrospectively reviewed. CXL was performed using the Dresden protocol or an accelerated protocol involving epithelial removal. RESULTS: All cases appeared normal on the day after surgery, but subsequently developed eye pain, blurred vision, corneal infiltration, inflammation of the anterior chamber, and ciliary injection on day 2 or 3. Methicillin-resistant Staphylococcus aureus was cultured from two eyes, methicillin-sensitive Staphylococcus aureus from two eyes, and Streptococcus pneumoniae from one eye. All detected bacteria were resistant to levofloxacin (LVFX). Five of the seven cases, especially four of the five severe cases with hypopyon, had a history of atopic dermatitis. All cases were observed after 2015. CONCLUSIONS: Infectious keratitis after CXL caused by microbes resistant to LVFX is increasing. In addition to careful postoperative observation of the cornea, preoperative evaluation of bacteria within the conjunctival sac evident on nasal swab cultures may be useful to identify potentially problematic microbes and inform the selection of appropriate antibiotics.


Assuntos
Ceratite , Ceratocone , Staphylococcus aureus Resistente à Meticilina , Córnea , Reagentes para Ligações Cruzadas , Feminino , Humanos , Ceratite/tratamento farmacológico , Ceratocone/tratamento farmacológico , Levofloxacino/uso terapêutico , Masculino , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico
18.
Nutrients ; 13(8)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34444772

RESUMO

Riboflavin, a water-soluble member of the B-vitamin family, plays a vital role in producing energy in mitochondria and reducing inflammation and oxidative stress. Migraine pathogenesis includes neuroinflammation, oxidative stress, and mitochondrial dysfunction. Therefore, riboflavin is increasingly being recognized for its preventive effects on migraines. However, there is no concrete evidence supporting its use because the link between riboflavin and migraines and the underlying mechanisms remains obscure. This review explored the current experimental and clinical evidence of conditions involved in migraine pathogenesis and discussed the role of riboflavin in inhibiting these conditions. Experimental research has demonstrated elevated levels of various oxidative stress markers and pro-inflammatory cytokines in migraines, and riboflavin's role in reducing these marker levels. Furthermore, clinical research in migraineurs showed increased marker levels and observed riboflavin's effectiveness in reducing migraines. These findings suggest that inflammation and oxidative stress are associated with migraine pathogenesis, and riboflavin may have neuroprotective effects through its clinically useful anti-inflammatory and anti-oxidative stress properties. Riboflavin's safety and efficacy suggests its usefulness in migraine prophylaxis; however, insufficient evidence necessitates further study.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Riboflavina/uso terapêutico , Animais , Humanos , Inflamação , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Vitaminas/uso terapêutico
19.
J Refract Surg ; 37(8): 562-569, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388071

RESUMO

PURPOSE: To compare 1-year visual and tomographic outcomes of topography-guided photorefractive keratectomy (TGPRK) and topography-assisted phototherapeutic keratectomy (TPTK) with corneal cross-linking (CXL). METHODS: TGPRK and TPTK were performed in 72 eyes (68 patients) and 74 eyes (71 patients), respectively. Based on the TGPRK ablation plan, the eyes underwent TPTK where the theoretical minimum corneal thickness (MCT) after surgery was less than 400 µm. In the TGPRK group, the theoretical maximum ablation depth was 50 µm after epithelium removal. In TPTK, a decentered single-step PTK was performed only in the steepest anterior curvature zone and the stromal ablation depth was limited to 25 µm. After ablation, accelerated CXL was performed in the central 8-mm zone (9 mW/cm2 for 10 minutes in "epithelium-off" mode) in both TGPRK and TPTK. The visual acuity and tomography were assessed. RESULTS: Improvement in uncorrected (P = .73) and corrected (P = .66) distance visual acuity was similar between the two groups. However, TGPRK eyes had a greater decrease in keratometry, anterior defocus, and spherical aberration (P < .001) at the cost of greater ablation of tissue (P < .001). The median MCT decreased by 27 and 52.5 µm in the TPTK and TGPRK eyes, respectively. Both groups had similar decreases in anterior root mean square of lower (P = .10) and higher (P = .12) order aberrations. CONCLUSIONS: Both TGPRK and TPTK improved visual acuity in the keratoconic eyes at 1 year of follow-up. However, TPTK removed less volume of tissue. Further, it could be an alternative to TGPRK if the theoretical stromal ablation exceeds 50 µm in thin keratoconic corneas. [J Refract Surg. 2021;37(8):562-569.].


Assuntos
Ceratocone , Fotoquimioterapia , Ceratectomia Fotorrefrativa , Substância Própria/cirurgia , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Humanos , Ceratocone/tratamento farmacológico , Ceratocone/cirurgia , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Prospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta
20.
Klin Lab Diagn ; 66(8): 465-471, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388316

RESUMO

A great deal of research was being done in studying of the age-related characteristics of carbohydrate metabolism and the provision of vitamins B1, B2 among the population of the Subarctic (SR) and Arctic (AR) regions, differing in the extreme natural and climatic-geographic living conditions. The surveyed population was divided into five age groups: 16-21, 22-35, 36-45, 46-60 and 61-74 years old. The parameters of carbohydrate metabolism (glucose, lactate, pyruvate) were determined in the blood serum, the content of thiamine (thiamin diphosphate effect) and riboflavin - in hemolysates, and the values of the lactate/pyruvate ratio (Lac/Pyr) were calculated. Statistical data processing was performed by nonparametric methods. An increase in glucose levels was found in persons of older age groups. Age-related fluctuations of metabolites of carbohydrate metabolism were manifested by a lower content of lactate and the value of the Lac/Pyr ratio in persons aged 16-21 years. Regardless of the age and region of the survey, there were revealed high lactate concentrations, Lac/Pyr values and reduced pyruvate levels, as well as low glucose levels in group aged 16-21 year in AR. For vitamins B1, B2, no pronounced age-related changes were observed, while the content of riboflavin was higher in persons of SR. Moderate hypovitaminosis of thiamin was detected in 13-20,1% and 6,1-22,7% of cases in SR and AR, pronounced - 8,3-11,6% and 4,6-23,5%, respectively, vitamin B2 deficiency was noted in 19,4-23,9% of persons in the AR and in 33,8-42,9% of persons in the AR. Vitamins in both regions at different age periods contributed to the formation of levels of indicators of carbohydrate metabolism: glucose and pyruvate in SR, lactate in AR.


Assuntos
Riboflavina , Tiamina , Adolescente , Adulto , Idoso , Metabolismo dos Carboidratos , Humanos , Ácido Pirúvico , Vitaminas , Adulto Jovem
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