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1.
Invest Ophthalmol Vis Sci ; 65(3): 5, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38466280

RESUMO

Purpose: The purpose of this study was to investigate the clinical significance of recurrent disc hemorrhage (DH) and choroidal microvasculature dropout (MvD). Methods: A retrospective cohort study was conducted of 181 eyes with open-angle glaucoma. The clinical characteristics of patients with nonrecurrent and recurrent DH with and without MvD were investigated. Results: Fifty-eight patients (32.0%) had a single, nonrecurrent DH, and 63 (34.8%) had more than one DH. Sixty eyes (33.1%) with no history of DH were presented as a control group. MvD was more frequent in the recurrent DH group (44.4%) than in the nonrecurrent DH group (27.6%, P = 0.041). The recurrent DH with MvD group experienced more frequent central visual field (VF) progression (71.4%) than the recurrent DH without MvD group (17.1 %, P < 0.001). The recurrent DH without MvD group had a higher frequency of DH recurrence at different locations (42.9%) and more vascular symptoms (37.1%) than the recurrent DH with MvD group (14.3% and 7.1%, P = 0.013 and P = 0.005, respectively). Presence of DH, presence of MvD, vascular symptoms, and DH recurrence at different locations were the factors associated with central VF progression in multivariate analysis. Conclusions: DH occurrence and the presence of MvDs constitute critical parameters associated with central VF progression. In the presence of MvD, recurrent DH was more likely to recur at the same location as the MvD, whereas recurrent DH without MvD was related to vascular symptoms and recurred at other locations. When eyes present with recurrent DH and MvD, closer follow-up and more aggressive treatment are required to prevent the progression of central VF.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Humanos , Tomografia de Coerência Óptica , Glaucoma de Ângulo Aberto/diagnóstico , Relevância Clínica , Estudos Retrospectivos , Microvasos , Hemorragia , Corioide , Angiografia
2.
Am J Ophthalmol ; 260: 160-171, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38191067

RESUMO

PURPOSE: To observe the development of glaucoma in myopic eyes with and without myopic optic neuropathy (MON) and analyze associated factors to the development of typical glaucomatous damage. DESIGN: A prospective, observational, cohort study. METHODS: A total of 233 myopic eyes with no definite evidence of glaucomatous damage were included. Myopic patients without any retinal nerve fiber layer (RNFL) or visual field (VF) abnormalities were classified as myopic eyes without MON. Myopic patients with decreased RNFL at the superonasal (SN) or nasal area, and with corresponding VF defects either in the temporal or inferotemporal (IT) region were classified as myopic eyes with MON. Myopic eyes that developed glaucoma were defined by the presence of glaucomatous VF in the SN region including defects in Bjerrum area, or a new localized RNFL defect in the IT region. Disc morphological features and optic nerve head (ONH) parameters of two groups were compared. RESULTS: Myopic eyes with MON had a thinner average peripapillary RNFL thickness (P < 0.001), worse MD of the VF (P = 0.031), a higher percentage of IT VF defects (P < 0.001), smaller torsion degree (P = 0.047), and greater LCD (P = 0.022). Myopic eyes with MON who developed glaucoma had a thinner average peripapillary RNFL thickness (P = 0.009), greater PPA area (P = 0.049), greater LCD (P < 0.001), and thinner LCT (P < 0.001). Thinner baseline temporal RNFL thickness (HR, 0.956; 95% CI, 0.928-0.986; P = 0.004), greater baseline LCD (HR, 1.003; 95% CI, 1.000-1.005; P = 0.022), and greater PPA area (HR, 1.000; 95% CI, 1.000-1.003; P = 0.050) were significantly associated factors with glaucoma development. CONCLUSIONS: Myopic eyes with MON have a greater risk to develop glaucoma compared to myopic eyes without MON. Structural weakness due to myopia, especially at the temporal side of the ONH and the peripapillary sclera, increases the risk of glaucoma in myopic eyes with MON.


Assuntos
Glaucoma , Miopia , Doenças do Nervo Óptico , Humanos , Estudos de Coortes , Estudos Prospectivos , Tomografia de Coerência Óptica , Glaucoma/complicações , Glaucoma/diagnóstico , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/etiologia , Miopia/complicações , Miopia/diagnóstico , Transtornos da Visão , Pressão Intraocular
3.
J Clin Med ; 12(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834909

RESUMO

The surface area of encapsulation around the Ahmed glaucoma valve (AGV) endplate is a critical factor in the surgical outcome as it is associated with the degree of IOP reduction. We investigated the surgical outcome of AGV implantation with an additional pericardium graft inserted adjacent to the endplate, with the intent of expanding the surface area of encapsulation. We enrolled 92 patients (92 eyes) who underwent AGV implantation. Of them, 50 patients underwent conventional surgery (termed the without-expansion group), and 42 received an additional an 8 × 6 mm pericardium graft inserted adjacent to the AGV endplate at the sub-Tenon's space (with-expansion). The hypertensive phase was classified as mild (>21 mmHg), moderate (>25 mmHg), and severe (>30 mmHg). Six months post-surgery, the with-expansion group exhibited a lower IOP (14.90 ± 4.27 mmHg) and lower peak IOP (22.29 ± 4.95 mmHg) than the without-expansion group (17.56 ± 4.88 mmHg and 25.06 ± 6.18 mmHg, p = 0.008 and p = 0.021, respectively). The with-expansion group exhibited a relatively low rate of moderate (16.7%) and severe (4.8%) hypertensive phases compared to the without-expansion group (40.0% and 20.0%, with p = 0.014 and p = 0.031, respectively). The additional pericardium graft was associated with a reduced occurrence of moderate hypertensive phase in both univariate and multivariate analysis logistic regression analyses (p = 0.017 and p = 0.038, respectively). Endplate surface area expansion using an additional pericardium graft reduced the occurrence of moderate and severe hypertensive phases, and lower postoperative 6-month IOP could be achieved.

4.
J Clin Med ; 12(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37568492

RESUMO

To explore various parameters that can evaluate the central visual impairment in patients with early-stage glaucoma, we included patients into a study with central visual impairments with an MD value greater than -6.0 dB on the 24-2 VF test. A possible association between structural parameters acquired by OCT and functional parameters of VF and PERG was determined. A total of 70 eyes of patients with suspected glaucoma or NTG underwent VF, OCT, and PERG examinations. The patients were classified into two groups according to the MD of the 24-2 VF test. We used Pearson correlation analysis to evaluate the relationships between GCIPL thickness/RNFL thickness and visual functional parameters, such as PERG and perimetry. Linear regression analyses were conducted to evaluate the significant factors affecting the PSD of VF 10-2. In the low MD group, the P50 amplitude presented significant correlations (r = 0.346, p = 0.048) with GCIPL thickness. In the correlation analysis of the high MD group, it was found that only the PSD of 10-2 uniquely presented borderline significant correlations with GCIPL thickness (r = -0.327, p = 0.055), and no other functional parameter showed significant correlation. Univariate and multivariate analyses revealed that GCIPL thickness was significantly associated with a PSD of 10-2 VF (p < 0.001 and 0.013, respectively). Among various parameters, the P50 amplitude and 10-2 PSD demonstrated statistically borderline significant structure-function relationships with GCIPL thickness in early-stage glaucoma.

5.
J Clin Med ; 12(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37445255

RESUMO

Superficial and deep macular vessel density (VD) is decreased in eyes with glaucoma. Superficial VD comprises both the retinal nerve fiber layer (RNFL) and ganglion cell/inner plexiform layer (GC/IPL), and various terms have been used previously to describe the layers of macular VD. In our study, we readjusted the macular segmentation. We obtained RNFL and GC/IPL VDs separately to evaluate VD changes of axon versus soma/dendrite of the retinal ganglion cells (RGCs) in detail. We included 66 eyes of normal tension glaucoma patients with inferior localized RNFL defects solely impacting the inferior hemiretina. Macular VD was measured as RNFL VD and GC/IPL VD. VD ratio was calculated by dividing the VD from the affected hemiretina by the VD from the unaffected hemiretina. RNFL VD ratio was related to RNFL and GC/IPL thicknesses (p = 0.005, p = 0.001), whereas GC/IPL VD ratio was not (p = 0.596, p = 0.783). A lower GC/IPL VD ratio was associated with lower RNFL VD (p = 0.017) and systemic hypertension (p = 0.03) in multivariate analysis. Patients with a reduced GC/IPL VD ratio were more prone to poor visual field defects (p = 0.022) and paracentral scotoma (p = 0.046) and more likely to be on treatment for systemic hypertension (p = 0.024). Therefore, glaucoma patients on systemic hypertension treatment and reduced GC/IPL VD require cautious management.

6.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37111313

RESUMO

We identify the angiotensin II (AngII)-associated changes in the extracellular matrix (ECM) and the biomechanical properties of the sclera after systemic hypotension. Systemic hypotension was induced by administering oral hydrochlorothiazide. AngII receptor levels and ECM components in the sclera and biomechanical properties were evaluated based on the stress-strain relationship after systemic hypotension. The effect of inhibiting the AngII receptor with losartan was determined in the systemic hypotensive animal model and the cultured scleral fibroblasts from this model. The effect of losartan on retinal ganglion cell (RGC) death was evaluated in the retina. Both AngII receptor type I (AT-1R) and type II (AT-2R) increased in the sclera after systemic hypotension. Proteins related to the activation of fibroblasts (transforming growth factor [TGF]-ß1 and TGF-ß2) indicated that transformation to myofibroblasts (α smooth muscle actin [SMA]), and the major ECM protein (collagen type I) increased in the sclera after systemic hypotension. These changes were associated with stiffening of the sclera in the biomechanical analysis. Administering losartan in the sub-Tenon tissue significantly decreased the expression of AT-1R, αSMA, TGF-ß, and collagen type I in the cultured scleral fibroblasts and the sclera of systemic hypotensive rats. The sclera became less stiff after the losartan treatment. A significant increase in the number of RGCs and decrease in glial cell activation was found in the retina after the losartan treatment. These findings suggest that AngII plays a role in scleral fibrosis after systemic hypotension and that inhibiting AngII could modulate the tissue properties of the sclera, resulting in the protection of RGCs.

7.
Arthroscopy ; 39(5): 1235-1241, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36517264

RESUMO

PURPOSE: to investigate the association between the lateral femoral condylar ratio (LFCR), the posterior tibial slope (PTS), and injury of the anterolateral ligament (ALL). METHODS: Inclusion criteria were patients with acute anterior cruciate ligament (ACL) tear after noncontact injury during sports from October 1997 to May 2021. The LFCR and PTS were measured, and injury of the ALL was evaluated. Patients were divided into 2 groups: isolated ACL tear (isolated group) and combined ACL with ALL tear (combined group). The LFCR and PTS were compared between the isolated and combined groups. For each risk factor, the receiver operating characteristic curve, the area under the curve (AUC), and its 95% confidence interval (CI) were calculated to determine the cutoff for detecting increased risk of ALL injury. RESULTS: There were 83 patients in the isolated group and 176 patients in the combined group. Demographics of the 2 groups did not differ significantly. The LFCR was significantly larger in the combined group than in the isolated group (P = .000). The PTS did not differ between the two groups (P = .405). The LFCR (odds ratio [OR] = 1.58; P = .000) was a significant factor. Age, body mass index, and PTS were not associated with an ALL injury. The AUC (0.79; 95% CI, 0.74-0.85) for the LFCR had a sensitivity of 73% and specificity of 76% to predict an ALL rupture. The calculated cutoff of 64.5 was associated with an increased risk for ALL rupture (OR = 8.65; 95% CI, 4.73-15.81) when compared with the isolated group. CONCLUSIONS: An increased LFCR was associated with the ALL injury. However, increased PTS was not associated with ALL injury. These findings need to be considered for clinicians in treating ACL tear patients at risk for an ALL injury. LEVEL OF EVIDENCE: III, retrospective comparative prognostic trial.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Lesões do Ligamento Cruzado Anterior/cirurgia , Estudos Retrospectivos , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Fêmur/cirurgia , Articulação do Joelho/cirurgia , Tíbia/cirurgia , Ligamentos , Imageamento por Ressonância Magnética
8.
J Clin Med ; 13(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38202211

RESUMO

We aimed to characterize and compare the occurrence of peripapillary microvasculature dropout (MvD) between glaucoma suspects and patients with glaucoma. In addition, the factors related to the development of parapapillary MvD in glaucoma suspects and patients with glaucoma were investigated. Of a total 150 eyes, 68 eyes of glaucoma suspects and 82 eyes of glaucoma patients were analyzed in this study. Univariate and multivariate logistic regression analyses were used to identify factors associated with MvD development. The classification of glaucoma patients or glaucoma suspects was not significantly associated with MvD development (beta 1.368, 95% CI, 0.718-2.608, p = 0.341). In the regression analysis of the glaucoma suspect group, greater axial length (beta 1.520, 95% CI, 1.008-2.291, p = 0.046) and baseline cup volume (beta 3.993, 95% CI, 1.292-12.345, p = 0.035) among the baseline factors and the slope of ganglion cell-inner plexiform layer (GCIPL) thickness (beta 0.027, 95% CI, 0.072-0.851, p = 0.027) and central visual field (VF) progression (beta 7.040, 95% CI, 1.781-16.306, p = 0.014) among follow-up factors were significantly associated with MvD development. In the glaucoma group, central VF progression (beta 5.985, 95% CI, 1.474-24.083, p = 0.012) and ONH depression (beta 3.765, 95% CI, 1.301-10.895, p = 0.014) among follow-up elements were observed as significant factors and the baseline factor had little relationship. MvD appears not only as a result of the progression of axonal loss of RGC in glaucoma but may also be developed due to structural changes and mechanical susceptibility of the ONH associated with baseline characteristics. Analyzing the structural susceptibility of the ONH can predict the occurrence of MvD, which can be helpful in predicting the progression of glaucoma.

10.
J Gen Virol ; 94(Pt 3): 497-506, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23175241

RESUMO

Epstein-Barr virus (EBV) is a herpesvirus associated with lymphomas and carcinomas. While EBV-associated epithelial cell lines are good model systems to investigate the role of EBV in carcinoma, only a few cell lines are available as they are hard to acquire. A greater variety of naturally EBV-infected cell lines which are derived from tumour patients are needed to represent various features of EBVaGC. We characterized cell line YCCEL1, established from a Korean EBVaGC patient, to ascertain whether it can be used to study the roles of EBV in EBVaGC. The expression of EBV genes and cell surface markers was examined by in situ hybridization, RT-PCR, Western blot analysis, immunofluorescence assay and Northern blot analysis. EBV episomal status was analysed by Southern blotting and real-time PCR. This cell line expressed EBV nuclear antigen 1 (EBNA1) and latent membrane protein 2A (LMP2A), but not EBNA2, LMP2B nor LMP1. The majority of the lytic proteins were not detected in YCCEL1 cells either before or after treatment with 12-O-tetradecanoylphorbol-13-acetate. YCCEL1 cells expressed BART microRNAs (miRNAs) at high level but did not express BHRF1 miRNAs. YCCEL1 cells expressed cytokeratin, but not CD21 and CD19, suggesting CD21-independent EBV infection. The latent EBV gene and EBV miRNA expression pattern of YCCEL1 cells closely resembled that of general EBVaGC cases. Our results support the value of YCCEL1 cells as a good model system to study the role of EBV in gastric carcinogenesis.


Assuntos
Carcinoma/virologia , Herpesvirus Humano 4/fisiologia , Neoplasias Gástricas/virologia , Southern Blotting , Linhagem Celular Tumoral , Regulação da Expressão Gênica/fisiologia , Genoma Viral , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
11.
Mol Cells ; 32(2): 173-9, 2011 08.
Artigo em Inglês | MEDLINE | ID: mdl-21626300

RESUMO

Epstein-Barr virus (EBV) is associated with human cancers such as nasopharyngeal carcinoma, Burkitt's lymphoma, Hodgkin's disease, and gastric carcinoma (GC). EBV is associated with about 10% of all GC cases globally. EBV-associated GC has distinct features from EBV-negative GC. However, it is still unclear if EBV infection has any effect on GC chemoresistance. Cell proliferation assay, cell cycle analysis, and active caspase Western blot revealed that the EBV-positive GC cell line (AGS-EBV) showed chemoresistance to docetaxel compared to the EBV-negative GC cell line (AGS). Docetaxel treatment increased expression of Bax similarly in AGS and AGS-EBV cell lines. However, Bcl-2 induction was markedly higher in AGS-EBV cells, after docetaxel treatment. Although docetaxel increased the expression of p53 to a similar extent in both cell lines, induction of p21 in AGS-EBV cells was lower than in AGS cells. Furthermore, expression of survivin was higher in AGS-EBV cells than in AGS cells following docetaxel treatment as well as at basal state. EBVlytic gene expression was induced by docetaxel treatment in AGS-EBV cells. The results suggest that EBV infection and lytic induction confers chemoresistance to GC, possibly by regulating cellular and EBV latent and lytic gene expression.


Assuntos
Carcinoma/tratamento farmacológico , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Herpesvirus Humano 4/fisiologia , Neoplasias Gástricas/tratamento farmacológico , Taxoides/uso terapêutico , Carcinoma/patologia , Carcinoma/virologia , Linhagem Celular Transformada , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Docetaxel , Resistencia a Medicamentos Antineoplásicos , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Survivina , Taxoides/farmacologia
12.
Arch Pharm Res ; 31(2): 250-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18365698

RESUMO

A novel polymeric salt of clopidogrel, clopidogrel resinate, was prepared as a anticoagulant drug. To prove the feasibility as a new active substance, clopidogrel resinate was evaluated for its efficacy and safety. In accelerated stability tests, the clopidogrel resinate tablet (Pregrel) showed less brown discoloration and fewer impurities than the clopidogrel bisulfate tablets under open and closed conditions. In toxicity tests, no deaths occurred after a single dose of up to 2000 mg/kg/day and 13-week repeated doses of up to 625 mg/kg/day in rats without abnormal symptoms compared to clopidogrel bisulfate. When clopidogrel resinate was treated onto Caco-2 cell monolayers, clopidogrel, but not the resin, permeated across the cells with a hight permeation coefficient (Papp) of 13.5 +/- 1.13 x 10(-6) cm/sec. Clopidogrel resinate and clopidogrel bisulfate showed similar pharmacokinetics following oral administration to beagle dogs. A single oral administration of clopidogrel resinate dose-dependently inhibited ADP-induced ex vivo aggregation up to 30 mg/kg in rats. In conclusion, clopidogrel resinate was proved to be an efficient and safe polymeric salt as a candidate for a new clopidogrel salt.


Assuntos
Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Ticlopidina/análogos & derivados , Animais , Tempo de Sangramento , Células CACO-2 , Fenômenos Químicos , Físico-Química , Clopidogrel , Cães , Estabilidade de Medicamentos , Trato Gastrointestinal/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal/efeitos dos fármacos , Masculino , Camundongos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/toxicidade , Polímeros , Ratos , Ratos Sprague-Dawley , Ticlopidina/química , Ticlopidina/farmacologia , Ticlopidina/toxicidade
13.
Int J Pharm ; 272(1-2): 79-89, 2004 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-15019071

RESUMO

The effect of hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) on the aqueous solubility and chemical stability of O-(4-Dimethylaminoethoxycinnamoyl)fumagillol (CKD-732), a new angiogenesis inhibitor, was investigated with an aim of preparing a stable and effective parenteral formulation. The CKD-732/HP-beta-CyD inclusion complex was obtained in solid state by freeze-drying and characterized in solution by proton nuclear magnetic resonance (1H NMR). Then, the pharmacokinetic profile in rats and the in vivo tumor growth inhibitory activity in mice following the parenteral administration of aqueous CKD-732/HP-beta-CyD complex were compared to those of CKD-732.hemioxalate solution having an equivalent concentration. The aqueous solubility of CKD-732 was markedly increased by the combination of pH adjustment and HP-beta-CyD complexation through a soluble 1:1 inclusion complex formation, which was supported by NMR spectroscopy. The hydrolysis of CKD-732 following pseudo first-order kinetics was decelerated moderately but significantly in acidic and basic solutions in the presence of HP-beta-CyD. The stability of lyophilized CKD-732/HP-beta-CyD complex was also drastically improved after storage in various conditions. The intravenous pharmacokinetic profile and the subcutaneous in vivo tumor growth inhibitory activity of aqueous CKD-732/HP-beta-CyD complex were not significantly different from those of CKD-732.hemioxalate solution with the favorable reduction of irritation. These results demonstrate that the CKD-732/HP-beta-CyD complex is an attractive formulation for use in the parenteral delivery of CKD-732.


Assuntos
Inibidores da Angiogênese/química , Cinamatos/química , Ciclodextrinas/química , Compostos de Epóxi/química , Sesquiterpenos/química , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacocinética , Animais , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/patologia , Cinamatos/administração & dosagem , Cinamatos/farmacocinética , Cicloexanos , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/farmacocinética , Hidrólise , Injeções Intravenosas , Camundongos , Soluções Farmacêuticas , Transição de Fase , Ratos , Ratos Sprague-Dawley , Sesquiterpenos/administração & dosagem , Sesquiterpenos/farmacocinética , Solubilidade , Fatores de Tempo
14.
J Biomater Sci Polym Ed ; 14(9): 951-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14661872

RESUMO

Norfloxacin-releasing urethral catheters were prepared for the purpose of preventing urinary tract infections during long-term catheterization. The outer and inner surfaces of the catheters were coated with poly(ethylene-co-vinyl acetate) (EVA) and an amphiphilic multiblock co-polymer (PEO2kPDMS), composed of poly(ethylene oxide) and poly(dimethyl siloxane). Norfloxacin, a fluoroquinolone synthetic antibiotic, was impregnated into a coating layer. The in vitro drug release behavior was monitored for 30 days, the surface topography was investigated using scanning electron microscopy (SEM) and the antibacterial activity against different bacteria implicated in urinary tract infection was evaluated by the in vitro inhibition zone test. All the coated catheters showed continuous delivery of norfloxacin for up to 30 days owing to hydrophobic natures of norfloxacin and EVA. PEO2kPDMS incorporated in a coating layer produced a smooth and uniform surface. The coated catheters created considerable inhibition zones for 10 days against Escherichia coli. Klebsiella pneumoniae and Proteus vulgaris, indicating the continuous release of norfloxacin. Overall, it was evident that the catheters coated with EVA/PEO2kPDMS blends containing norfloxacin have a promising potential for the clinical use in patients undergoing long-term catheterization.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Norfloxacino/administração & dosagem , Cateterismo Urinário/métodos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Norfloxacino/farmacologia , Fatores de Tempo , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Infecções Urinárias/prevenção & controle
15.
J Biomater Sci Polym Ed ; 14(9): 963-72, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14661873

RESUMO

Urethral catheters, widely used for the drainage of the bladder, are associated with most urinary tract infections (UTIs) that account for 40% of all episodes occurring in acute-care hospitals. This study aimed to develop a gentamicin-releasing catheter that effectively prevents UTIs for short-term catheterization. For physical loading of gentamicin, the urethral catheters were coated by the simple dipping method with poly(ethylene-co-vinyl acetate) (EVA) and EVA/poly(ethylene oxide) (PEO) blends containing gentamicin. By varying the molecular weight (MW) and contents of PEO in the blends, various catheter surfaces were produced. In vitro drug release studies demonstrated that all the coated catheters exhibited sustained release up to 7 days; however, the release pattern was significantly dependant on the coating layers. Of the coated catheters, EVA/PEO (MW = 100k)-coated catheters were utilized to evaluate the antibacterial activity using an inhibition zone test, since they showed a promising drug release behavior and had PEO-rich biocompatible surfaces. In accordance with drug release behavior, EVA/PEO-coated catheters exhibited antibacterial activities for 7 days against Proteus vulgaris, Staphylococcus aureus and Staphylococcus epidermidis. These results imply that the catheters coated with EVA/PEO have a potential for short-term catheterization.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Gentamicinas/administração & dosagem , Cateterismo Urinário/métodos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Gentamicinas/farmacologia , Fatores de Tempo , Cateterismo Urinário/efeitos adversos
16.
Int J Pharm ; 239(1-2): 207-11, 2002 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-12052706

RESUMO

(20S)-7-(2-isopropylamino)ethylcamptothecin.HCl (CKD-602), a new camptothecin (CPT) anticancer agent, is a pale yellowish crystalline compound. DSC thermogram exhibited a melt endotherm near 270 degrees C, and CKD-602 was found to be slightly hygroscopic. The solubility of CKD-602 in deionized water was 8.22 mg/ml, and two pK(a) values were measured to be 2.32 and 9.15, respectively. A pH-dependent partition coefficient behavior in octanol-buffer was observed. CKD-602 in solid state was stable over the range of temperature and humidity, but decomposed slightly by light. The hydrolysis of CKD-602 occurred reversibly and rapidly in aqueous buffer solutions. The conversion rate constants (k(f): from the lactone to the carboxylate and k(r): from the carboxylate to the lactone) and the final equilibrium ratio (K(eq)) between two species were dependent on the pH of aqueous solutions.


Assuntos
Antineoplásicos Fitogênicos/química , Camptotecina/análogos & derivados , Camptotecina/química , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Umidade , Concentração de Íons de Hidrogênio , Hidrólise , Solubilidade , Solventes , Temperatura
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