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1.
J Photochem Photobiol B ; 204: 111782, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32062389

RESUMO

BACKGROUND: Ultraviolet (UV) fluorescent lamp (FL) was applied in mainstream riboflavin photochemical method (RPM) to inactivate pathogens in blood components. Low UV irradiance emitted by UV-FL resulted in more time to achieve effective inactivation. MATERIALS AND METHODS: A novel light emitting diode (LED) UV illumination with adjustable irradiance was developed by us. Two strains of drug-resistant bacteria (DRB), pan-drug resistant Acinetobacter baumannii (PDRAB) and methicillin-resistant Staphylococcus aureus (MRSA) were cultured and used for evaluating the inactivation effectiveness of RPM using UV-LED or UV-FL against DRB in plasma or platelets. Three plasma factors and four platelet parameters were measured after treatments. RESULTS: There was a linear relationship between UV-LED irradiance and electric current, the minimum UV irradiance was 24 mW/cm2, and the maximum was 258 mW/cm2. At the same UV dose of 15 J/cm2, inactivation effectiveness of UV-LED with 258 mW/cm2 against PDRAB in plasma or platelets were comparable to that of UV-FL with 16 mW/cm2, both above 98%. UV-FL treatment required 10-15 min, but UV-LED only required 1-2 min. However, MRSA showed a resistance to UV-LED (inactivation effectiveness was around 40%) compared with UV-FL (inactivation effectiveness was above 98%). The retention of fibrinogen, factor V, factor VII in plasma and platelet counts in platelets with UV-LED treatment were significantly higher than UV-FL at the same UV dose. CONCLUSION: The treatment of RPM using UV-LED with high UV irradiance was able to dramatically shorten inactivation time against PDRAB in plasma or platelets and improve retention of blood components compared with UV-FL.


Assuntos
Proteínas Sanguíneas/metabolismo , Riboflavina/química , Raios Ultravioleta , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/efeitos da radiação , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/efeitos da radiação , Farmacorresistência Bacteriana/efeitos dos fármacos , Fator V/metabolismo , Fibrinogênio/metabolismo , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Contagem de Plaquetas , Riboflavina/farmacologia
2.
Int J Mol Sci ; 20(15)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374832

RESUMO

Chronic inflammation can lead to tumour initiation and progression. Vitamin B complex has the ability to regulate the immune response and, therefore, inflammation but many of the mechanistic and molecular processes involved in this regulation are still not fully understood. This study sought to determine some of these processes by studying the effects of vitamin B2 (riboflavin) B6 (pyridoxine) and B9 (folic acid) on un-differentiated pro-monocytic lymphoma cells in regard to their ability to alter the proliferation, migration, apoptosis, cytokines and expression levels of programmed death ligand 1. We show that vitamin B2, B6 and B9, on pro-monocytic lymphoma cells exerted an anti-tumorigenic effect. This data could form the basis for future studies in using vitamin B supplementation to reduce cancer cell growth in vivo.


Assuntos
Anticarcinógenos/farmacologia , Ácido Fólico/farmacologia , Linfoma/tratamento farmacológico , Riboflavina/farmacologia , Vitamina B 6/farmacologia , Adulto , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Linfoma/patologia , Masculino
3.
Dent Med Probl ; 56(2): 143-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31274252

RESUMO

BACKGROUND: The cross-linking of collagen fibers in the hybrid layer has been suggested as a way to create more durable bonds. OBJECTIVES: This study evaluated the effect of visible light-activated riboflavin (RF) as a cross-linking agent on the durability of the dentin microtensile bond strength (µTBS) in a 2-step self-etch (SE) adhesive system. MATERIAL AND METHODS: The occlusal surfaces of 21 human premolar teeth were ground down to expose the dentin, and were then randomly divided into 3 groups. The Clearfil® SE Bond was used in the control group. In the RF/BL group, a 0.1 wt% aqueous solution of RF was applied to the dentin surface before applying the adhesive and irradiating with blue light (BL) for 2 min. In the 3rd group, the RF-P/BL group, the RF powder was added to the adhesive primer (P) at a concentration of 0.1 wt%. The teeth were built up using composite resin. After thermocycling, 14 resin-dentin beams from each group were prepared and stored in water for 3 months. The µTBS was determined and the data was analyzed using a linear model with a generalized estimating equation (GEE) (p = 0.05). RESULTS: The highest and the lowest µTBS belonged to the control group (41.15 ±3.50 MPa) and the RF-P/BL group (19.84 ±3.80 MPa), respectively. The mean µTBS in the control group was significantly higher than in the RF/BL and RF-P/BL groups (p < 0.001), but no significant difference was found between the RF/BL and RF-P/BL groups (p = 0.598). CONCLUSIONS: Pre-treatment of dentin surfaces with RF activated with BL had a negative impact on the µTBS of the Clearfil SE Bond as a 2-step SE adhesive.


Assuntos
Colagem Dentária , Adesivos Dentinários , Riboflavina , Cimentos Dentários , Dentina , Humanos , Cimentos de Resina , Riboflavina/farmacologia , Estresse Mecânico , Resistência à Tração
4.
Genes (Basel) ; 10(7)2019 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-31284601

RESUMO

Previous study has demonstrated that the riboflavin treatment promoted the early ripening of the 'Kyoho' grape berry. However, the molecular mechanism causing this was unclear. In order to reveal the regulation mechanism of riboflavin treatment on grape berry development and ripening, the different berry developmental stages of the 'Kyoho' berry treated with 0.5 mmol/L of riboflavin was sampled for transcriptome profiling. RNA-seq revealed that 1526 and 430 genes were up-regulated and down-regulated, respectively, for the comparisons of the treatment to the control. TCseq analysis showed that the expression patterns of most of the genes were similar between the treatment and the control, except for some genes that were related to the chlorophyll metabolism, photosynthesis-antenna proteins, and photosynthesis, which were revealed by the enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differentially expressed genes and weighted gene co-expression network analysis (WGCNA) analysis identified some significantly differentially expressed genes and some hub genes, including up-regulation of the photosynthesis-related ELIP1 and growth and development-related GDSL; and down-regulation of the oxidative stress-related ATHSP22 and berry softening-related XTH32 and GH9B15. The results suggested that the riboflavin treatment resulted in the variations of the expression levels of these genes, and then led to the early ripening of the 'Kyoho' berry.


Assuntos
Frutas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Riboflavina/farmacologia , Vitis/efeitos dos fármacos , Frutas/genética , Vitis/genética
5.
Ophthalmic Plast Reconstr Surg ; 35(6): 600-603, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31348113

RESUMO

PURPOSE: A follow-up experimental study on the exposure of animal tarsal plate to ultraviolet-A radiation aimed at establishing an optimum range for safe irradiation conditions. METHODS: Sheep tarsus specimens were excised postmortem and then subjected to irradiation with ultraviolet-A rays (wavelength 365 nm) at higher irradiances than those reported in an initial study, using a laboratory radiation source. The mechanical properties (tensile strength and Young's modulus) of irradiated and nonirradiated samples were evaluated in a mechanical tester. The test and control specimens were examined histologically with an aim to assess the effects of radiation upon the meibomian glands and tarsal collagen networks, and to establish a safe range for the exposure irradiance level. RESULTS: As expected, irradiation induced both stiffening and strengthening of the tarsal plate specimens. At an irradiance of 50 mW/cm for 3-minute exposure, these effects were at their maximum level, after which a decline in mechanical characteristics were observed. No destruction of the tarsal connective tissue or the meibomian glands were noticed up to an irradiance of 125 mW/cm for 3-minute exposure, corresponding to a fluence of 22.5 J/cm. Histology revealed that the collagen network surrounding the glands were packed more compactly following irradiation. At a fluence of 45 J/cm, massive destruction of periglandular collagen-rich network and meibocytes were demonstrated histologically. CONCLUSIONS: The study indicates that irradiation of tarsal collagen leading to tissue stiffening shall be carried out at levels of fluence between 10 and 15 J/cm, a region that is deemed safe. The exposure time can be adjusted according to the surgeon's decision.Safe irradiation conditions are established for the exposure of ex vivo ovine tarsus to ultraviolet-A radiation as a potentially effective treatment for eyelid laxity in human patients.


Assuntos
Colágeno/metabolismo , Reagentes para Ligações Cruzadas/farmacologia , Doenças Palpebrais/tratamento farmacológico , Pálpebras , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Animais , Pálpebras/efeitos dos fármacos , Pálpebras/fisiologia , Pálpebras/efeitos da radiação , Glândulas Tarsais/efeitos dos fármacos , Glândulas Tarsais/efeitos da radiação , Ovinos , Raios Ultravioleta
6.
Cornea ; 38(7): 864-867, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31170104

RESUMO

PURPOSE: To assess corneal thickness changes with isotonic riboflavin (RF) solution with hydroxylpropyl methylcellulose in patients undergoing accelerated corneal collagen crosslinking (CXL) with and without an eyelid speculum. METHODS: Fifty-two eyes of 48 patients with progressive keratoconus were enrolled in this study. The patients in this study were divided into 2 groups: in group 1 an eyelid speculum was removed during 20-minute RF (0.1%) + hydroxylpropyl methylcellulose (Mediocross M; Avedro Inc, Waltham, MA) instillation, and in group 2 the eyelid speculum was retained in place during the entire CXL procedure. All patients underwent accelerated CXL using continuous ultraviolet-A (UVA) light exposure at 9 mW/cm for 10 minutes; total energy dose was 5.4 J/cm. Intraoperative ultrasound pachymetry measurements were obtained before and after epithelial removal, after RF loading, and after UVA light exposure at 5 and 10 minutes. RESULTS: The preoperative pachymetric measurements decreased in both groups after the removal of epithelium [group 1 (n = 26): -25 µm, group 2 (n = 26): -31 µm, P = 0.234]. Although the thinnest pachymetry significantly increased after soaking in both group 1 (52.26 µm) and group 2 (27.88 µm, P < 0.001), closure of the eyelids during RF instillation further increased the pachymetry readings (P < 0.0001). The corneal thickness remained stable in both groups during UVA irradiation at 5 and 10 minutes (P > 0.05). CONCLUSIONS: Closure of the eyelids further induces corneal swelling that may offer an advantage to improve safety of the procedure particularly in thin corneas.


Assuntos
Colágeno/metabolismo , Córnea/efeitos dos fármacos , Derivados da Hipromelose/uso terapêutico , Ceratocone/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Adolescente , Adulto , Criança , Reagentes para Ligações Cruzadas/uso terapêutico , Feminino , Humanos , Derivados da Hipromelose/farmacologia , Masculino , Fotoquimioterapia/instrumentação , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Instrumentos Cirúrgicos , Raios Ultravioleta , Adulto Jovem
7.
Graefes Arch Clin Exp Ophthalmol ; 257(7): 1443-1452, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31041523

RESUMO

PURPOSE: To evaluate the efficacy of corneal cross-linking (CXL) as adjuvant therapy for the treatment of fungal ulcerative keratitis. METHODS: Forty-one patients with fungal ulcerative keratitis were recruited and assigned into two randomized controlled groups. These groups were treated with CXL combined with antifungal medications (CXL-M) or antifungal medications alone (M). The ulcers were assessed by slit-lamp biomicroscopy, slit-lamp images, in vivo confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT). The patients were followed up before surgery/first visit (FV), 1 day after surgery, 1 and 2 weeks, and 1, 2, 3, 4, 5, and 6 months after surgery/FV. RESULTS: In the cured patients, the area of corneal ulcers, the duration of ulcer healing, the time to non-observed fungal hyphae by IVCM, the number of antifungal medications, the frequency of administered medications, and the maximum ulcer depth decreased significantly after CXL (all P < 0.05) compared with the M group. There were no significant differences in either corneal thickness or epithelial thickness of ulcers after healing between 5 and 6 months after surgery in the CXL-M group, while these were increased significantly at 6 months compared with 5 months after FV in the M group (both P < 0.05). CONCLUSIONS: In our study, CXL accelerated healing of the fungal ulcers, shortened the treatment duration, and minimized the need for medications and surgery. It appears that CXL is an effective procedure and adjuvant therapy for managing fungal keratitis.


Assuntos
Antifúngicos/farmacologia , Córnea/patologia , Úlcera da Córnea/tratamento farmacológico , Reagentes para Ligações Cruzadas/farmacologia , Infecções Oculares Fúngicas/tratamento farmacológico , Fotoquimioterapia/métodos , Riboflavina/farmacologia , Córnea/microbiologia , Úlcera da Córnea/diagnóstico , Úlcera da Córnea/microbiologia , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/microbiologia , Feminino , Seguimentos , Fungos/isolamento & purificação , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/farmacologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Raios Ultravioleta
8.
J Photochem Photobiol B ; 196: 111496, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129507

RESUMO

Surgical resection is one of the most common radical treatments for cancers. However, tumors may be compressed or the local intravascular pressure may be increased during surgical manipulation, causing the shedding and entry of tumor cells into the blood circulation and hence distant recurrence and metastasis of tumors. We have preliminarily established a method of riboflavin photosensitization treatment (RPT) for inactivation of circulating tumor cells. This technology promises to solve the problems of shedding and entry of solid tumor cells into blood circulation before surgical manipulation, and almost unavoidable hematogenous dissemination of tumor cells during surgical resection. In the present study, apoptosis detection and tumorigenicity experiment in immunodeficient mice were conducted to evaluate the effect of RPT for inactivation of circulating tumor cells respectively. Next, functional evaluation was carried out for the immune cells through detecting apoptosis rate and cytokine secretion of lymphocyte. Finally, thromboelastography (TEG) and free hemoglobin were detected to assess peripheral blood coagulation and red blood cell damage. The results showed that RPT (50 µmol/L riboflavin, 10.8 J/cm2 UV) could effectively make tumor cell lose the ability of proliferation in the peripheral blood. In the meantime, the damage caused to peripheral blood coagulation, immune cell function and red blood cells was generally acceptable. The results of the study showed that RPT had huge potential in addressing the problems of shedding and entry of solid tumor cells into blood circulation before surgical manipulation, and almost unavoidable hematogenous dissemination of tumor cells during surgical resection. This therapy is expected to be an auxiliary and supportive method to reduce the risk of hematogenous metastasis and recurrence of cancers, and to increase the surgical success rate of malignant solid tumors.


Assuntos
Células Neoplásicas Circulantes/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Coagulação Sanguínea/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Células HCT116 , Hemólise/efeitos dos fármacos , Humanos , Luz , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias/tratamento farmacológico , Células Neoplásicas Circulantes/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico
9.
Graefes Arch Clin Exp Ophthalmol ; 257(7): 1435-1442, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31065848

RESUMO

PURPOSE: To investigate the safety of blue light scleral cross-linking (SXL) by evaluating changes in biological parameters in the retina and choroid in the eyes of rhesus macaques (Macaca mulatta). METHODS: Fifteen 3-year-old macaques (30 eyes) were randomly divided into three groups (n = 5). SXL was performed via riboflavin (0.5%) and blue light (460 nm) at the location of the equatorial sclera. Right eyes served as experimental eyes, and left eyes as control eyes. One quadrant of each right eye was irradiated in group A, two quadrants of each right eye and one quadrant of each left eye were irradiated in group B, and two quadrants of each right eye were irradiated in group C. Optical coherence tomography, optical coherence tomography angiography, and flash electroretinography (f-ERG) examinations were performed at baseline and 1 week, 1 month, 3 months, and 6 months after SXL. Additionally, retinal tissue alterations were detected via transmission electron microscopy at 1 week postoperatively. RESULTS: There were no significant differences between experimental eyes and control eyes in retinal thickness, vessel density of retinal superficial capillary plexus, and choroid thickness in any of the groups at any of the time points investigated (p > 0.05). Significant reductions in f-ERG parameters were detected 1 week postoperatively in the experimental eyes of groups A and C (p < 0.05), but they gradually recovered, and there was no significant difference 1 month postoperatively (p > 0.05). Ultrastructural changes were evident in the retinal layers of SXL eyes. In group B, there were no significant differences between the right and left eyes at any of the follow-up time points investigated. CONCLUSIONS: Blue light SXL can cause transient retina damage. The f-ERG parameters reductions and retinal ultrastructural changes were found at early stage, even though there were not significant changes in retinal thickness, vessel density of retinal superficial capillary plexus, and choroid thickness after blue light SXL. The long-term intraocular safety of the blue light SXL technique should be investigated further.


Assuntos
Corioide/patologia , Colágeno/farmacologia , Reagentes para Ligações Cruzadas/farmacologia , Miopia/tratamento farmacológico , Fotoquimioterapia/métodos , Retina/patologia , Riboflavina/farmacologia , Animais , Modelos Animais de Doenças , Eletrorretinografia , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Luz , Macaca mulatta , Miopia/diagnóstico , Miopia/fisiopatologia , Fármacos Fotossensibilizantes/farmacologia , Esclera , Tomografia de Coerência Óptica , Resultado do Tratamento
10.
J Refract Surg ; 35(5): 333-339, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31059583

RESUMO

PURPOSE: To evaluate the ocular biological parameter difference between scleral corneal cross-linking (CXL) and control eyes in rhesus monkeys by using a rebound tonometer, A-scan ultrasonography, retinoscopy, optical coherence tomography, and electroretinography (ERG). METHODS: Six rhesus monkeys were used in this study, with ages ranging from 3 to 3.5 years. One eye of each rhesus monkey was randomly selected to receive riboflavin/ultraviolet-A CXL in the temporal quadrant of the equatorial sclera and the contralateral eye served as an intra-individual control. The ocular biological parameters were repeatedly measured in both eyes of the monkeys before scleral CXL and 1 week, 1 month, and 3 months postoperatively. RESULTS: The intraocular pressure, refractive state, total axial length, and axial dimensions of the anterior chamber, crystalline lens, vitreous chamber, and central corneal thickness were not statistically significantly different between the control and cross-linked specimens at the different time periods (each P > .05). No obvious changes in the waveform of the standard full-field ERGs were observed in the control and cross-linked specimens. There were no statistically significant differences between the control and cross-linked specimens in the dark-adapted 0.01 ERG, the dark-adapted 3.0 ERG, the light-adapted 3.0 ERG, and the amplitudes of the a-wave and b-wave for the different time periods (each P >.05). CONCLUSIONS: The scleral CXL laboratory technique might not significantly affect the ocular biological parameters of the rhesus monkey in the early postoperative period, but long-term effects and histological changes still need to be investigated further. [J Refract Surg. 2019;35(5):333-339.].


Assuntos
Colágeno/metabolismo , Reagentes para Ligações Cruzadas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Esclera/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Biometria , Eletrorretinografia , Pressão Intraocular/fisiologia , Macaca mulatta , Masculino , Retina/fisiologia , Esclera/metabolismo , Tomografia de Coerência Óptica , Tonometria Ocular , Raios Ultravioleta
11.
Lasers Med Sci ; 34(9): 1799-1805, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30929100

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of infections in humans. Photodynamic therapy using blue light (450 nm) could possibly be used to reduce MRSA on different human tissue surfaces without killing the human cells. It could be less harmful than 300-400 nm light or common disinfectants. We applied blue light ± riboflavin (RF) to MRSA and keratinocytes, in an in vitro liquid layer model, and compared the effect to elimination using common disinfection fluids. MRSA dilutions (8 × 105/mL) in wells were exposed to blue light (450 nm) ± RF at four separate doses (15, 30, 56, and 84 J/cm2). Treated samples were cultivated on blood agar plates and the colony forming units (CFU) determined. Adherent human cells were cultivated (1 × 104/mL) and treated in the same way. The cell activity was then measured by Cell Titer Blue assay after 24- and 48-h growth. The tested disinfectants were chlorhexidine and hydrogen peroxide. Blue light alone (84 J/cm2) eliminated 70% of MRSA. This dose and riboflavin eradicated 99-100% of MRSA. Keratinocytes were not affected by blue light alone at any dose. A dose of 30 J/cm2 in riboflavin solution inactivated keratinocytes completely. Disinfectants inactivated all cells. Blue light alone at 450 nm can eliminate MRSA without inactivation of human keratinocytes. Hence, a high dose of blue light could perhaps be used to treat bacterial infections without loss of human skin cells. Photodynamic therapy using riboflavin and blue light should be explored further as it may perhaps be possible to exploit in treatment of skin diseases associated with keratinocyte hyperproliferation.


Assuntos
Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Luz , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Fotoquimioterapia , Riboflavina/farmacologia , Linhagem Celular , Ensaio de Unidades Formadoras de Colônias , Humanos
12.
Photodiagnosis Photodyn Ther ; 26: 306-312, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31002887

RESUMO

BACKGROUND: Although antimicrobial photodynamic therapy (aPDT) has been shown to be efficient in killing planktonic periodontopathogenic bacteria, its activity on established biofilms is very limited. The aim of the present in-vitro study was to evaluate the potential effect of hydrogen peroxide as a pretreatment for aPDT. METHODS: aPDT consisting of riboflavin as photosensitizer and illumination by a LED lamp emitting in the blue spectrum for 30 s and 60 s (aPDT60) was combined with a pretreatment with 0.25% and 3% hydrogen peroxide. The antimicrobial activity of these treatments was determined against eight oral species (incl. Porphyromonas gingivalis and Tannerella forsythia) and against eight-species biofilms. Treatment of biofilms in an artificial pocket model included a mechanical removal of the biofilm. RESULTS: Against planktonic bacteria, pretreatment with hydrogen peroxide increased killing of planktonic bacteria, after aPDT60 no viable bacteria were detected in 7 of 8 strains. In biofilms formed on well-plates, aPDT60 reduced bacterial counts only by 0.53 log10 cfu, whereas reduction was closed to 4 log10 or higher when 3% hydrogen peroxide was used. When biofilms were treated in the periodontal-pocket model, reduction of cfu was less than 0.5 log10 after mechanical therapy or aPDT60 only, however no bacteria were detected after mechanical biofilm removal followed by the use 3% of hydrogen peroxide and aPDT60. CONCLUSIONS: aPDT using riboflavin and blue LED light applied after mechanical removal of biofilm and adjunctive 3% hydrogen peroxide solution appears to represent an alternative for antimicrobial periodontal therapy.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/microbiologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Técnicas In Vitro , Riboflavina/farmacologia
13.
J Refract Surg ; 35(4): 253-260, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30984983

RESUMO

PURPOSE: To investigate the stiffening effect of localized corneal cross-linking (L-CXL) within and beyond the irradiated region in three dimensions. METHODS: Ten porcine eyes were debrided of epithelium and incrementally soaked with 0.1% riboflavin solution. Using a customized, sharp-edged mask, half of the cornea was blocked while the other half was exposed to blue light (447 nm). The three-dimensional biomechanical properties of each cornea were then measured via Brillouin microscopy. An imaging system was used to quantify the optimal transition zone between cross-linked and non-cross-linked sections of the cornea when considering light propagation and scattering. RESULTS: A broad transition zone of 610 µm in width was observed between the fully cross-linked and non-cross-linked sections, indicating the stiffening response extended beyond the irradiated region. Light propagation and the scattering induced by the riboflavin-soaked cornea accounted for a maximum of 25 and 159 ± 3.2 µm, respectively. CONCLUSIONS: The stiffening effect of L-CXL extends beyond that of the irradiated area. When considering L-CXL protocols clinically, it will be important to account for increased stiffening in surrounding regions. [J Refract Surg. 2019;35(4):253-260.].


Assuntos
Córnea/fisiopatologia , Reagentes para Ligações Cruzadas , Elasticidade/fisiologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Fenômenos Biomecânicos , Colágeno/metabolismo , Córnea/efeitos dos fármacos , Córnea/metabolismo , Substância Própria/metabolismo , Imageamento Tridimensional , Riboflavina/farmacologia , Suínos , Raios Ultravioleta
14.
Nutrients ; 11(4)2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31010085

RESUMO

Because age-related hearing loss (ARHL) is irreversible, prevention is very important. Thus, investigating modifying factors that help prevent ARHL is critical for the elderly. Nutritional status or nutritional factors for the elderly are known to be associated with many problems related to aging. Emerging studies suggest that there was the interaction between nutrition and ARHL. We aimed to investigate the possible impact of dietary nutrients on ARHL using data from the fifth Korean National Health and Nutrition Examination Survey (KNHANES) which included 4742 subjects aged ≥ 65 years from 2010 to 2012. All participants underwent an otologic examination, audiologic evaluation, and nutritional survey. The associations between ARHL and nutrient intake were analyzed using simple and multiple regression models with complex sampling adjusted for confounding factors, such as BMI, smoking status, alcohol consumption, and history of hypertension and diabetes. Higher intake groups of riboflavin, niacin and retinol was inversely associated with ARHL prevalence (riboflavin aOR, 0.71; 95% CI, 0.54-0.94; p = 0.016, niacin aOR, 0.72; 95% CI, 0.54-0.96; p = 0.025, retinol aOR 0.66; 95% CI, 0.51-0.86; p = 0.002, respectively). Our findings suggest the recommended intake levels of riboflavin, niacin, and retinol may help reduce ARHL in the elderly.


Assuntos
Envelhecimento , Dieta , Perda Auditiva/prevenção & controle , Niacina/uso terapêutico , Estado Nutricional , Riboflavina/uso terapêutico , Vitamina A/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Ingestão de Energia , Feminino , Perda Auditiva/etiologia , Humanos , Masculino , Niacina/administração & dosagem , Niacina/farmacologia , Inquéritos Nutricionais , Razão de Chances , Análise de Regressão , República da Coreia , Riboflavina/administração & dosagem , Riboflavina/farmacologia , Vitamina A/administração & dosagem , Vitamina A/farmacologia , Vitaminas/administração & dosagem , Vitaminas/farmacologia , Vitaminas/uso terapêutico
15.
Cornea ; 38(6): 780-790, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30882538

RESUMO

PURPOSE: There has been a recent explosion in the variety of techniques used to accomplish corneal cross-linking (CXL) for the treatment of ectatic corneal diseases. To understand the success or failure of various techniques, we review the physicochemical basis of corneal CXL and re-evaluate the current principles and long-standing conventional wisdom in the light of recent, compelling, and sometimes contradictory research. METHODS: Two clinicians and a medicinal chemist developed a list of current key topics, controversies, and questions in the field of corneal CXL based on information from current literature, medical conferences, and discussions with international practitioners of CXL. RESULTS: Standard corneal CXL with removal of the corneal epithelium is a safe and efficacious procedure for the treatment of corneal ectasias. However, the necessity of epithelium removal is painful for patients, involves risk and requires significant recovery time. Attempts to move to transepithelial corneal CXL have been hindered by the lack of a coherent understanding of the physicochemistry of corneal CXL. Misconceptions about the applicability of the Bunsen-Roscoe law of reciprocity and the Lambert-Beer law in CXL hamper the ability to predict the effect of ultraviolet A energy during CXL. Improved understanding of CXL may also expand the treatment group for corneal ectasia to those with thinner corneas. Finally, it is essential to understand the role of oxygen in successful CXL. CONCLUSIONS: Improved understanding of the complex interactions of riboflavin, ultraviolet A energy and oxygen in corneal CXL may provide a successful route to transepithelial corneal CXL.


Assuntos
Colágeno/metabolismo , Córnea , Doenças da Córnea/tratamento farmacológico , Reagentes para Ligações Cruzadas/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Raios Ultravioleta , Córnea/efeitos dos fármacos , Córnea/efeitos da radiação , Epitélio Anterior/efeitos dos fármacos , Epitélio Anterior/efeitos da radiação , Humanos
16.
Vox Sang ; 114(3): 207-215, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734299

RESUMO

BACKGROUND AND OBJECTIVES: Alloimmunization is common following transfusion with platelet-rich plasma (PRP) and can cause complications such as platelet refractoriness or transplant rejection. It has previously been shown that pathogen reduction of PRP with riboflavin and UV light (UV+R) can protect against alloimmunization in mice and induce partial tolerance to subsequent transfusions. MATERIALS AND METHODS: Using B6 H2d congenic mice, this study evaluated the relative contributions of major histocompatibility complex (MHC) antigens and minor antigens to both the alloresponse to PRP transfusion and the partial tolerance induced by UV+R treatment. RESULTS: Both total and MHC-specific alloantibody responses were highest when both MHC and minor antigens were mismatched, with lower alloantibody responses observed with MHC mismatch alone, demonstrating that allogeneic minor antigens can enhance the response to allogeneic MHC. There was a weak, but significant alloantibody response to minor antigens only. UV+R treatment protected against both major and minor antigen alloimmunization. Both allogeneic MHC and minor antigens primed an enhanced cytokine response ex vivo, though this was weaker with minor antigens, and both responses were blocked with UV+R treatment. CONCLUSION: Allogeneic MHC is both necessary and sufficient to induce the partial tolerance associated with UV+R treatment.


Assuntos
Plaquetas/imunologia , Tolerância Imunológica , Complexo Principal de Histocompatibilidade/imunologia , Transfusão de Plaquetas/métodos , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/efeitos da radiação , Isoanticorpos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Transfusão de Plaquetas/efeitos adversos , Riboflavina/farmacologia , Raios Ultravioleta
17.
Chem Biol Interact ; 302: 135-142, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30776357

RESUMO

Riboflavin (Rf) or vitamin B2 is a known photosensitizer whose photophysical and photochemical properties are well established. Aminophylline (Am) is a phosphodiesterase inhibitor and is currently used as a bronchodilator. Although there are several reports of haemolytic and proteolytic interaction of photoilluminated riboflavin with aminophylline, the cytotoxicity of this system against malignant tissue is not well defined and fully unravelled. Here, we are evaluating anticancer activity of this system against B(a)P induced lung carcinoma in swiss albino mice. We observed marked increment in the level of cellular redox scavengers as well as oxidative stress markers. A significant DNA damage was observed using comet assay. Histopathological studies further confirmed induction of apoptosis in lung tissues of Am-Rf treated animals. Scanning electron microscopy revealed altered surface morphology of the malignant tissue, which characteristically improved in the treatment group. Since malignancy is characterised by compromised redox status, therefore, further increment in ROS due to the action of this system derives cellular system towards extensive macromolecular damage and consequent ROS mediated apoptosis. We anticipate the usage of this system in developing efficient photodynamic therapy against lung cancer that can be clinically realised.


Assuntos
Aminofilina/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Riboflavina/farmacologia , Aminofilina/uso terapêutico , Animais , Benzopirenos/toxicidade , Dano ao DNA/efeitos dos fármacos , Luz , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/veterinária , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico
18.
Vox Sang ; 114(3): 223-231, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30784069

RESUMO

BACKGROUND: Transmission of pathogens through blood transfusion is still of great concern to clinicians, patients and blood providers. Pathogen reduction technologies (PRT) have been successfully applied for the treatment of labile blood components, such as plasma, platelets and whole blood (WB), which are now used in routine in many countries. We report the clinical evaluation of suspension of red blood cells (RBC-S) derived from the WB treated with riboflavin and UV light (RF+UV). STUDY DESIGN AND METHODS: Seventy paediatric patients (0·3-17·1 years old) suffering from different malignant disorders were recruited and assigned to two groups: the control group (C) received transfusions of γ-irradiated RBC-S. The experimental group (T) received RBC-S derived from WB, treated with RF+UV. Clinical efficacy was evaluated during follow-up periods by Hb and Ht increments, and needs for transfusion support. Safety was assessed through active surveillance, recording post-transfusion reactions, anti-erythrocyte's antibody formation, haptoglobin and serum potassium levels. RESULTS: The clinical efficacy of RBC-S in both groups was similar: mean post-transfusion Hb concentration (101·6 ± 7·57 g/l vs. 100 ± 8·3 g/l; P = 0·43), and Ht level (28·5 ± 2·42% vs. 28·2 ± 2·7%; P = 0·66). Transfusion of pathogen-reduced RBC-S did not increase the frequency of transfusion reactions and did not induce an excessive immune response in the follow-up period. CONCLUSION: Transfusion of RBC-S, obtained from pathogen-reduced WB, is a promising method to increase the safety of blood component therapy for paediatric patients with malignant disorders without affecting clinical efficacy. A randomized clinical trial including more patients should follow this pilot study to confirm its results.


Assuntos
Segurança do Sangue/métodos , Transfusão de Eritrócitos/métodos , Reação Transfusional/epidemiologia , Adolescente , Criança , Pré-Escolar , Contagem de Eritrócitos , Transfusão de Eritrócitos/normas , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Feminino , Humanos , Lactente , Masculino , Riboflavina/farmacologia , Reação Transfusional/prevenção & controle , Raios Ultravioleta
19.
Life Sci Alliance ; 2(1)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30659069

RESUMO

d-amino acid oxidase (DAO) is a flavin adenine dinucleotide (FAD)-dependent oxidase metabolizing neutral and polar d-amino acids. Unlike l-amino acids, the amounts of d-amino acids in mammalian tissues are extremely low, and therefore, little has been investigated regarding the physiological role of DAO. We have recently identified DAO to be up-regulated in cellular senescence, a permanent cell cycle arrest induced by various stresses, such as persistent DNA damage and oxidative stress. Because DAO produces reactive oxygen species (ROS) as byproducts of substrate oxidation and the accumulation of ROS mediates the senescence induction, we explored the relationship between DAO and senescence. We found that inhibition of DAO impaired senescence induced by DNA damage, and ectopic expression of wild-type DAO, but not enzymatically inactive mutant, enhanced it in an ROS-dependent manner. Furthermore, addition of d-amino acids and riboflavin, a metabolic precursor of FAD, to the medium potentiated the senescence-promoting effect of DAO. These results indicate that DAO promotes senescence through the enzymatic ROS generation, and its activity is regulated by the availability of its substrate and coenzyme.


Assuntos
Senescência Celular/fisiologia , D-Aminoácido Oxidase/genética , D-Aminoácido Oxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Aminoácidos/metabolismo , Arginina/metabolismo , Senescência Celular/efeitos dos fármacos , Coenzimas/metabolismo , D-Aminoácido Oxidase/antagonistas & inibidores , Dano ao DNA/genética , Flavina-Adenina Dinucleotídeo/metabolismo , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Oxirredução , Interferência de RNA , Riboflavina/farmacologia , Serina/metabolismo , Transfecção
20.
Mater Sci Eng C Mater Biol Appl ; 96: 30-40, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606536

RESUMO

Novel l­Arginine­Dextran70 based-silver nanoparticles (SNPs) (SNPsArg), functionalized with Riboflavin (RF) and Human Serum Albumin (HSA) were characterized by UV-Vis absorption, Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), fluorescence and circular dichroism spectroscopy, chemiluminescence and Neutral red assays. TEM analysis showed the formed faceted particles, large clumps/fused aggregates, nano-featured with the mean particle size of 41.60 nm. Chemiluminescence and Neutral red assays for in vitro antioxidant and cytotoxic activities of the SNPsArg/RF/HSA systems have been studied. It was pointed out that SNPsArg functionalized with RF and HSA resulted in a bio-nanosystem which leads to a high activity against oxygen free radicals, altered viability, morphology, apoptotic bodies and decreased cell density of L929 fibroblast cells. Results are relevant for understanding the redox properties of RF in the case of biological applications and especially for RF containing drugs.


Assuntos
Arginina/química , Dextranos/química , Fibroblastos/metabolismo , Nanopartículas/química , Biossíntese de Proteínas/efeitos dos fármacos , Riboflavina/farmacologia , Albumina Sérica Humana/farmacologia , Prata/química , Animais , Linhagem Celular , Fibroblastos/citologia , Humanos , Camundongos
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