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International Journal of Molecular... May 2021The potential of tannic acid (TA) as a dispersing agent for graphene (G) in aqueous solutions and its interaction with riboflavin have been studied under different...
The potential of tannic acid (TA) as a dispersing agent for graphene (G) in aqueous solutions and its interaction with riboflavin have been studied under different experimental conditions. TA induces quenching of riboflavin fluorescence, and the effect is stronger with increasing TA concentration, due to π-π interactions through the aromatic rings, and hydrogen bonding interactions between the hydroxyl moieties of both compounds. The influence of TA concentration, the pH, and the G/TA weight ratio on the quenching magnitude, have been studied. At a pH of 4.1, G dispersed in TA hardly influences the riboflavin fluorescence, while at a pH of 7.1, the nanomaterial interacts with riboflavin, causing an additional quenching to that produced by TA. When TA concentration is kept constant, quenching of G on riboflavin fluorescence depends on both the G/TA weight ratio and the TA concentration. The fluorescence attenuation is stronger for dispersions with the lowest G/TA ratios, since TA is the main contributor to the quenching effect. Data obey the Stern-Volmer relationship up to TA 2.0 g L and G 20 mg L. Results demonstrate that TA is an effective dispersant for graphene-based nanomaterials in liquid medium and a green alternative to conventional surfactants and synthetic polymers for the determination of biomolecules.
Topics: Fluorescence; Graphite; Hydrogen Bonding; Hydrogen-Ion Concentration; Hydroxyl Radical; Riboflavin; Spectrometry, Fluorescence; Surface-Active Agents; Tannins; Water
PubMed: 34067835
DOI: 10.3390/ijms22105270 -
Scientific Reports Dec 2022Although probiotics are often indiscriminately prescribed, they are not equal and their effects on the host may profoundly differ. In vitro determination of the...
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 β-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 β-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.
Topics: Antioxidants; Probiotics; Limosilactobacillus reuteri; beta-Galactosidase; Mucins; Lactates; Riboflavin
PubMed: 36517529
DOI: 10.1038/s41598-022-25688-z -
Asia-Pacific Journal of Ophthalmology... Dec 2020Corneal collagen cross-linking (CXL) with riboflavin is an accepted universal standard of care for our keratoconus patients with progressive disease. It has been a game... (Review)
Review
Corneal collagen cross-linking (CXL) with riboflavin is an accepted universal standard of care for our keratoconus patients with progressive disease. It has been a game changer in how we manage keratoconus. Early diagnosis and treatment is essential in paediatric patients as younger patients progress more rapidly and have poorer transplant outcomes. There is an ongoing debate around standard, accelerated, and transepithelial protocols of CXL, the role of CXL, and the combination of laser refractive surgery. Future developments will improve CXL safety and efficacy and the scope of utilization, but we must be careful not to leap too far ahead with clinical applications before publication of basic science research and good clinical results with standardized protocols.
Topics: Collagen; Corneal Topography; Cross-Linking Reagents; Health Knowledge, Attitudes, Practice; Humans; Keratoconus; Photochemotherapy; Photosensitizing Agents; Riboflavin; Treatment Outcome; Ultraviolet Rays; Visual Acuity
PubMed: 33323709
DOI: 10.1097/APO.0000000000000335 -
The British Journal of Ophthalmology Nov 2020To investigate the long-term safety and efficacy of accelerated transepithelial cornealcross-linking (ATE-CXL) in children with progressive keratoconus.
PURPOSE
To investigate the long-term safety and efficacy of accelerated transepithelial cornealcross-linking (ATE-CXL) in children with progressive keratoconus.
METHODS
Fifty-three eyes of 41 paediatric patients (34 boys, 7 girls; mean age 14.81±1.96 years) undergoing ATE-CXL were enrolled in the study. Corrected distance visual acuity (CDVA) and manifest refraction were assessed preoperatively and 36 months postoperatively. Corneal keratometry, corneal thickness and posterior elevation were measured using Pentacam preoperatively and 1, 6, 12 and 36 months postoperatively. Pachymetry and epithelial thicknesses were measured using optical coherence tomography preoperatively and 6, 12, and 36 months postoperatively.
RESULTS
Thirty-six months postoperatively, CDVA improved from 0.32±0.28 to 0.26±0.25 in logarithm of the minimum angle resolution (p=0.025). Maximum keratometry was 58.73±9.70 D preoperatively and 59.20±10.24, 58.28±9.33, 57.88±9.99 and 58.98±10.79 D at 1, 6, 12 and 36 months postoperatively throughout the 36-month follow-up period (p>0.05). Similarly, corneal central thickness, which was 492.42±33.83 µm postoperatively, also remained stable during the 36-month follow-up (p>0.05). Both posterior central elevation and posterior highest elevation were stable at 12 months after ATE-CXL (p>0.05), but increased at 36 months postprocedure (p<0.05). Corneal pachymetry and epithelial thicknesses remained stable throughout the follow-up period (p>0.05).
CONCLUSIONS
ATE-CXL is a safe and effective treatment in paediatric progressive keratoconus patients, leading to stable keratometry and corneal thickness throughout the 36-month follow-up.
Topics: Adolescent; Collagen; Corneal Pachymetry; Corneal Stroma; Corneal Topography; Cross-Linking Reagents; Female; Follow-Up Studies; Humans; Keratoconus; Male; Photochemotherapy; Photosensitizing Agents; Prospective Studies; Riboflavin; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Ultraviolet Rays; Visual Acuity
PubMed: 32051139
DOI: 10.1136/bjophthalmol-2019-315260 -
Cornea Jul 2023The aim of this study was to assess changes in visual acuity after epithelium-on ("epi-on") corneal crosslinking after a diagnosis of keratoconus. (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
The aim of this study was to assess changes in visual acuity after epithelium-on ("epi-on") corneal crosslinking after a diagnosis of keratoconus.
METHODS
Subjects with corneal ectatic diseases were enrolled in a prospective, randomized, controlled, open-label, multicenter trial. Subjects were randomized to 1 of 3 treatment groups and treated with an epi-on crosslinking system including riboflavin/sodium iodide and pulsed UVA exposure (EpiSmart, CXL Ophthalmics, Encinitas, CA). The UVA treatment groups were 2.4 J/cm 2 over 20 minutes, 3.6 J/cm 2 over 20 minutes, and 3.6 J/cm 2 over 30 minutes. The primary end point was logarithm of the minimum angle of resolution corrected distance visual acuity (CDVA). Secondary end points were logarithm of the minimum angle of resolution uncorrected distance visual acuity (UCVA), maximum corneal curvature (Kmax), and minimum corneal thickness. Data were assessed 6 and 12 months post-operatively, using t -tests for differences from baseline.
RESULTS
Two thousand two hundred twenty-eight subjects were treated with epi-on crosslinking. One thousand nine hundred twenty-two subjects had a diagnosis of keratoconus; other treated eyes had postsurgical and other ectasias. At 6 and 12 months, the subjects with keratoconus demonstrated significant improvements in CDVA, UCVA, and Kmax; minimum corneal thickness was unchanged. One hundred ninety-five subjects (8.7%) reported at least 1 adverse event (AE). A mild corneal epithelial defect was reported in 31 cases (1.4%) and was the only AE reported in >1% of subjects. There were no serious AEs related to the treatment.
CONCLUSIONS
EpiSmart epi-on crosslinking resulted in mean improvements in CDVA, UCVA, and Kmax at both 6 and 12 months and an excellent safety and efficacy profile in subjects with keratoconus, with few significant side effects. Differences between UVA treatment groups were not significant.
Topics: Humans; Keratoconus; Photosensitizing Agents; Photochemotherapy; Prospective Studies; Ultraviolet Rays; Corneal Topography; Cross-Linking Reagents; Collagen; Riboflavin; Dilatation, Pathologic
PubMed: 36173242
DOI: 10.1097/ICO.0000000000003136 -
Indian Journal of Ophthalmology May 2023Corneal cross-linking (CXL), a corneal strengthening procedure, is known to alter anterior stroma swelling behavior and is one of the treatment modalities of bullous... (Review)
Review
Corneal cross-linking (CXL), a corneal strengthening procedure, is known to alter anterior stroma swelling behavior and is one of the treatment modalities of bullous keratopathy (BK). There are multiple studies published on the role of CXL in the treatment of BK. These articles had heterogeneous study population, different protocols used, and variable conclusions. This systematic review aimed to determine the role of CXL in the treatment of BK. The primary outcomes considered were changes in central corneal thickness (CCT) after 1, 3, and 6 months of CXL. The secondary outcome measures were changes in visual acuity, corneal clarity, subjective symptoms, and complications after CXL. We included randomized control trials (RCTs), observational and interventional studies, and case series with reports of more than 10 cases in this review. In RCTs, the mean pre-CXL CCT (794.0 ± 178.5 μm) in the intervention group (n = 37), decreased at 1 month (750.9 ± 154.3 μm) followed by a subsequent increase, but this difference was not significant during the 6-month follow-up (P- value 0.28, 0.82, and 0.82 at 1, 3, and 6 months, respectively). In noncomparative clinical studies (n = 188), the mean pre-CXL CCT (794.0 ± 178.5 μm) decreased at 1 month (710.9 ± 127.2 μm, P < 0.0001). Seven of the 11 articles included in the review reported no significant improvement in vision with CXL. The initial improvement in corneal clarity and clinical symptoms was not sustained. Current evidence suggests that CXL has short-term efficacy in the treatment of BK. More RCTs with high-quality evidence are needed.
Topics: Humans; Corneal Cross-Linking; Photosensitizing Agents; Riboflavin; Ultraviolet Rays; Collagen; Cross-Linking Reagents; Corneal Stroma; Keratoconus; Corneal Topography
PubMed: 37203022
DOI: 10.4103/ijo.IJO_1942_22 -
Biomolecules Feb 2023Tryptophan is an essential amino acid and a precursor of a number of physiologically important metabolites, including serotonin, melatonin, tryptamine, and kynurenines....
Tryptophan is an essential amino acid and a precursor of a number of physiologically important metabolites, including serotonin, melatonin, tryptamine, and kynurenines. We assessed tryptophan, kynurenines, and vitamin B2 and B6, as well as biomarkers of liver function and inflammation, in a group of 158 female omnivores and vegetarians aged 18-40 years. The majority of women were omnivores, and 22% were vegetarians. Vegetarians had 25% lower serum ALT, significantly higher pyridoxal concentrations, and significantly lower plasma concentrations of most kynurenines, varying from 8% lower concentrations of median plasma kynurenine to 42% lower concentrations of plasma xanthurenic acid, compared to omnivores. No significant differences were observed in vitamin B2 status or in inflammation markers, C-reactive protein and neopterin between the groups. Vegetarians had lower levels of several plasma kynurenines compared to omnivores. The reason for this is unknown; however, lower ALT concentrations, suggesting a better liver status, and a more favourable vitamin B6 status might be contributing factors.
Topics: Humans; Female; Kynurenine; Tryptophan; Diet, Vegetarian; Riboflavin; Inflammation; Biomarkers
PubMed: 36830760
DOI: 10.3390/biom13020391 -
Animal : An International Journal of... Jan 2021Alternatives to riboflavin (vitamin B) production by recombinant microorganisms are needed in organic poultry production, but are cost-intensive, so that a...
Alternatives to riboflavin (vitamin B) production by recombinant microorganisms are needed in organic poultry production, but are cost-intensive, so that a demand-oriented riboflavin supply is necessary. Details on the riboflavin requirements of organic poultry are not available. A feed material with high native riboflavin content from fermentation of the filamentous fungus Ashbya gossypii was studied. Two runs with 800 Ranger Gold™ broilers each (40 pens with 20 animals) were conducted. The fattening period was divided into starter (S), grower (G) and finisher (F) stage. In the first run, a basal diet without riboflavin supplementation (NATIVE; 3.27, 3.50 and 3.16 mg riboflavin/kg DM in S, G and F) was compared to diets with supplementation at low (LOW; 5.30, 4.85 and 5.19 mg/kg in S, G and F), medium (MEDIUM; 7.56, 6.88 and 7.56 mg/kg in S, G and F) and high (HIGH; 10.38, 9.14 and 9.93 mg/kg in S, G and F) dosage. In the second run, different combinations of low and medium riboflavin supplementation were used in S, G and F diets: S-LOW (4.50 mg riboflavin/kg DM), G-MEDIUM (6.66 mg/kg), F-MEDIUM (5.71 mg/kg) (Treatment A), S-LOW (4.50 mg riboflavin/kg DM); G-LOW (4.92 mg/kg), F-LOW (4.01 mg/kg) (Treatment B); S-MEDIUM (6.37 mg/kg), G-MEDIUM (7.37 mg/kg), F-MEDIUM (5.07 mg/kg) (Treatment C); S-MEDIUM (6.37 mg/kg), G-LOW (5.28 mg/kg), F-LOW (4.22 mg/kg) (Treatment D). Body weight, feed and water consumption were recorded weekly, health and welfare indicators were scored bi-weekly. Slaughter traits were assessed for five males and females per pen. In the first run, NATIVE animals showed symptoms of riboflavin deficiency and lower live weights in the second week of age. Riboflavin contents of this group were increased to avoid further deficiency and recovery was observed. Feed conversion was better in HIGH (2.07) compared with NATIVE and LOW (2.11). At slaughter, treatments differed neither for foot pad dermatitis nor plumage cleanliness. In the second run, daily weight gains did not differ between treatments in any of the weeks. Feed conversion ranged between 1.99 and 2.04. Riboflavin deficiency was not observed in the second run, while treatment D showed superior economic efficiency. In conclusion, native contents of feed components (3.27 mg/kg DM) were not sufficient to meet the riboflavin demand and a total content of 4.50 mg/kg DM was identified as safe lower threshold. The levels rather according to commercial recommendations were not additionally beneficial to performance and health.
Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Chickens; Diet; Eremothecium; Female; Fermentation; Male; Riboflavin
PubMed: 33516011
DOI: 10.1016/j.animal.2020.100003 -
Veterinary Medicine and Science Jul 2022This study was conducted to evaluate the effect of adding riboflavin to boar sperm freezing extender on the challenge of cryopreservation.
OBJECTIVES
This study was conducted to evaluate the effect of adding riboflavin to boar sperm freezing extender on the challenge of cryopreservation.
METHODS
Different concentrations (0, 5, 10, 15, 20 or 25 μM) of riboflavin were added to the freezing extender. Spermatozoa motility, membrane integrity, acrosomal integrity, mitochondrial membrane potential and enzyme activities were analysed once 10 min after thawing. Q-PCR was used to detect the mRNA expression of Caspase3, Bcl-2 and Bax.
RESULTS
The results showed that the addition of 10 μM riboflavin to boar sperm freezing extender significantly increased the frozen-thawed sperm progressive motility compared with the control group (p < 0.05). Activities of superoxide dismutase, glutathione peroxidase and catalase improved after adding riboflavin to the extender (p < 0.05). During freezing-thawing, the boar sperm mitochondrial membrane potential, acrosomal integrity, plasma membrane and DNA at 10 μM in the riboflavin group increased by 6.6%, 9.6%, 5.49% and 5.62% (p < 0.05), respectively, compared with the control group. The addition of 10 μM riboflavin to the extender significantly decreased the malondialdehyde (p < 0.05) content, whereas it increased the ATP content (p < 0.05) of boar sperm during freezing-thawing. Furthermore, the expression of Caspase-3 and Bax (p < 0.05) were significantly lower, whereas the expression of BCL-2 (p < 0.05) was greater than the control group when adding 10 μM riboflavin to the extender.
CONCLUSIONS
Riboflavin showed cryoprotective capacity to the freezing extender used for boar sperm during the process of freezing-thawing, and the optimal concentration of riboflavin for the frozen extender was 10 μM.
Topics: Animals; Antioxidants; Cryopreservation; Cryoprotective Agents; Male; Riboflavin; Semen Preservation; Sperm Motility; Spermatozoa; Swine; bcl-2-Associated X Protein
PubMed: 35561277
DOI: 10.1002/vms3.833 -
Indian Journal of Ophthalmology Dec 2020Contact lens-assisted corneal cross-linking (CACXL) was introduced by Jacob et al. in 2012 for treating thin keratoconic corneas using riboflavin soaked soft contact... (Review)
Review
Contact lens-assisted corneal cross-linking (CACXL) was introduced by Jacob et al. in 2012 for treating thin keratoconic corneas using riboflavin soaked soft contact lens to artificially increase the functional corneal thickness. It is advantageous over other thin corneal cross-linking techniques as it works independent of swelling properties of the cornea, is an epi-off technique and does not require additional time, additional expensive equipments or special solutions. The only additional requirement as compared to all other techniques is a UV barrier-free soft contact lens (Soflens, B&L) which is easily available and inexpensive. Advantages include simplicity, easy adaptability, early visual rehabilitation, good visual outcomes, safety, and efficacy. Progression rates are acceptable and the need for re-treatment has been low. CACXL can help regularize corneal shape and may be used in isolation or synergistically with Intracorneal ring segments (ICRS) or Corneal allogenic intrastromal ring segments (CAIRS). It gives about 70% stiffening as compared to standard Dresden protocol CXL in less ideal porcine eye studies. Murine eye models that closely mimic thin corneas and show greater cross-linking effect as compared to porcine eyes may be a better model for evaluation of CACXL, however further studies are needed. Care should be taken in selecting the right kind of contact lens. Proper technique should be followed, especially by confirming thinnest functional pachymetry to be above 400 microns intra-operatively before application of UV-A. The sub-contact lens riboflavin film should be avoided as also an excessively thick supra-contact lens riboflavin film and too many re-applications.
Topics: Animals; Collagen; Contact Lenses; Cornea; Corneal Pachymetry; Corneal Stroma; Cross-Linking Reagents; Keratoconus; Mice; Photochemotherapy; Photosensitizing Agents; Riboflavin; Swine; Ultraviolet Rays
PubMed: 33229652
DOI: 10.4103/ijo.IJO_2138_20