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1.
Jpn J Ophthalmol ; 68(3): 200-205, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38587787

RESUMEN

PURPOSE: To evaluate the surgical outcomes of intrascleral intraocular lens (IOL) fixation using ab interno trabeculotomy (LOT) in patients with exfoliation glaucoma with lens subluxation. STUDY DESIGN: Retrospective case series. METHODS: Twenty eyes of 18 patients with exfoliation glaucoma and lens or IOL subluxations were included. Three success criteria were based on postoperative intraocular pressure (IOP) (A, ≤15 mmHg; B, ≤18 mmHg; C, ≤21 mmHg). The IOP, number of glaucoma medications, and visual acuity were compared before and after surgery. Success probability was analyzed using Kaplan-Meier survival curves. Cox proportional hazards' regression models were used to examine prognostic factors for surgical failure. RESULTS: The mean follow-up period was 23.4 ± 7.8 months. The mean IOP significantly decreased from 23.2 ± 6.8 mmHg preoperatively to 14.0 ± 4.4 mmHg at 1 year postoperative (P<0.001). Postoperative hyphema and vitreous hemorrhage were observed in seven and 15 eyes, respectively, and washout in the anterior chamber or vitreous cavity was performed in four eyes. Postoperative IOP spikes and hypotony were observed in four eyes each. Glaucoma reoperation was performed in two eyes. The success rates at 12 months were 65%, 85%, and 90% using criteria A, B, and C, respectively. The IOP at 1 month after surgery was a significant prognostic factor for surgical failure according to criterion A (hazard ratio: 1.08; P=0.034). CONCLUSION: Intrascleral IOL fixation combined with microhook LOT is a promising option in cases of exfoliation glaucoma with subluxated lens/IOL; however, the high rate of postoperative hyphema and vitreous hemorrhage should be noted.


Asunto(s)
Síndrome de Exfoliación , Presión Intraocular , Implantación de Lentes Intraoculares , Subluxación del Cristalino , Esclerótica , Trabeculectomía , Agudeza Visual , Humanos , Estudios Retrospectivos , Masculino , Femenino , Anciano , Esclerótica/cirugía , Síndrome de Exfoliación/fisiopatología , Síndrome de Exfoliación/cirugía , Síndrome de Exfoliación/complicaciones , Trabeculectomía/métodos , Presión Intraocular/fisiología , Agudeza Visual/fisiología , Subluxación del Cristalino/cirugía , Subluxación del Cristalino/fisiopatología , Subluxación del Cristalino/diagnóstico , Estudios de Seguimiento , Persona de Mediana Edad , Implantación de Lentes Intraoculares/métodos , Anciano de 80 o más Años , Lentes Intraoculares , Resultado del Tratamiento
2.
Artículo en Inglés | MEDLINE | ID: mdl-38446202

RESUMEN

PURPOSE: This study is to investigate the relationship between long-term changes in the foveal avascular zone (FAZ) and visual function of eyes with macular hole (MH) and compare the relationship between the FAZ of MH eyes and fellow eyes. METHODS: This study included 31 patients with unilateral MH who underwent vitrectomy and their fellow eyes. Best-corrected visual acuity (BCVA) and metamorphopsia were measured preoperatively and at 1, 3, 6, and 12 months postoperatively. We evaluated retinal parameters using optical coherence tomography (OCT) and the superficial FAZ using OCT angiography. The FAZ ratio was defined as follows: (preoperative FAZ area of the MH eye)/(FAZ area of the fellow eye). RESULTS: The preoperative FAZ area of MH eyes was 0.42 ± 0.08 mm2, which decreased to 0.24 ± 0.07 mm2 1 month postoperatively (p < 0.001) and slightly increased to 0.25 ± 0.06 mm2 12 months postoperatively (p = 1.000). The FAZ area did not differ significantly from that of fellow eyes (0.39 ± 0.06 mm2, p = 0.281). The FAZ area of MH eyes was not associated with visual function at any time point. The FAZ ratio showed a correlation with the preoperative, 6-month, and 12-month BCVA (r = 0.604, p < 0.001; r = 0.510, p = 0.003; and r = 0.475, p = 0.007, respectively). CONCLUSIONS: A larger FAZ in the MH eye than that in the fellow eye is associated with poorer long-term visual acuity. The preoperative comparison of the FAZ of the MH eye with that of the fellow eye may be a biomarker for predicting long-term visual acuity.

3.
Am J Ophthalmol Case Rep ; 28: 101729, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36324629

RESUMEN

Purpose: To describe a case of bilateral diffuse uveal melanocytic proliferation (BDUMP) with secondary angle closure caused by ciliary body thickening accompanied by intraocular pressure (IOP) elevation after mydriasis. Observations: A 55-year-old woman with a history of ovarian cancer had blurred vision in both eyes. Fundus examination revealed multiple patchy lesions in both eyes and a nevus-like elevated lesion in the right eye. Anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM) demonstrated angle closure resulting from ciliary body thickening. After mydriasis, the IOP was elevated in both eyes. Instillation of a miotic drug successfully reversed the IOP to normal levels. Conclusions and Importance: BDUMP caused secondary angle closure in both eyes, presumably due to thickening of the entire ciliary body. AS-OCT and UBM were advantageous for analyzing the morphology of the anterior eye segment in BDUMP. Clinicians should be aware of the possibility of angle closure during the management of patients with BDUMP.

4.
J Vet Med Sci ; 84(6): 784-791, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35400675

RESUMEN

Cancer-associated fibroblasts (CAFs) play an essential role in tumor invasion and metastasis. In dogs, the biological features of CAFs have not been well characterized. The purpose of this study was to investigate differences in the biological activities of canine CAFs and normal fibroblasts (NFs), and their influence on the migration and invasion of cancer cells. Canine CAFs and NFs were harvested from surgically-resected malignant epithelial tumor tissues and skin tissues of dogs. A wound-healing assay was conducted to compare the migratory and invasive abilities of canine CAFs and NFs. The results of this study showed that canine CAFs have a greater migratory and invasive ability than NFs. To observe the indirect and direct interactions between fibroblasts and cancer cells, Boyden chamber assay and 3D co-culture with collagen gel were conducted. The number of migrated and infiltrated cancer cells co-cultured with canine CAFs was greater than that with NFs. In the 3D co-culture, cancer cells showed noteworthy proliferation on the surface of gels containing canine CAFs and invasion into the gel. On the other hand, no infiltration of cancer cells into the gel containing NFs was observed. It was suggested that canine CAFs activate migration and invasion of cancer cells and promote the infiltration of cancer cells into collagen gels.


Asunto(s)
Fibroblastos Asociados al Cáncer , Enfermedades de los Perros , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Enfermedades de los Perros/patología , Perros , Fibroblastos/metabolismo , Invasividad Neoplásica/patología
5.
Animals (Basel) ; 13(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36611644

RESUMEN

A 9-year-old, 4.7 kg, spayed female Chihuahua presented with a 3.5 cm soft tissue sarcoma on the dorsal right thoracic wall. The tumor was resected, including the 11−13th ribs, resulting in a caudal dorsal thoracic wall defect. The defect was reconstructed with direct traction of part of the diaphragm dorsally, preserving the diaphragmatic attachments to the body wall, and the diaphragm was sutured to the surrounding ribs and muscles. Possible respiratory complications, including paradoxical respiration and exercise intolerance, were not observed during the perioperative or postoperative observation periods. This novel procedure is expected to be an option for caudal thoracic wall reconstruction when the diaphragmatic attachments remain intact even after the resection of the last rib. In addition, this procedure can be performed in dogs weighing <5 kg, with small pleural cavities and without respiratory disorders.

6.
Graefes Arch Clin Exp Ophthalmol ; 259(11): 3251-3259, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34097112

RESUMEN

PURPOSE: To evaluate the postoperative visual function using a preoperative epiretinal membrane (ERM) classification based on the status of the inner layer structure. METHODS: We assessed 62 eyes, one from each patient undergoing vitrectomy with internal limiting membrane (ILM) peeling for unilateral ERM. The inclusion criteria were as follows: (1) the presence of idiopathic ERM based on optical coherence tomography and a healthy contralateral eye, (2) successful surgery after 25- or 27-gauge transconjunctival 3-port pars plana vitrectomy with ILM peeling, and (3) a minimum follow-up period of 12 months. We included patients with preoperative ERM morphology with no disruption of the inner retinal layer in group A (37 eyes) and those with disruption in group B (25 eyes) and compared the visual acuity, central visual-field sensitivity (CVFS) measured using the Humphrey field analyzer 10-2 program, and detection rate of micro-scotoma (< 10 dB) at baseline and 12 months postoperatively between the groups. RESULTS: Visual acuity at 12 months showed greater improvement in group A than in group B (P = .03). There was no significant difference in CVFS at baseline; however, that of the nasal area was substantially lower after surgery in group B than in group A (P = .02). The 12-month postoperative detection rate of micro-scotoma was significantly higher in group B than in group A (P = .002). CONCLUSION: ERM that has preoperatively disrupted the inner layer poses the risks of CVFS reduction and micro-scotoma formation after vitrectomy. Evaluating the inner layer could be an important prognostic factor in determining retinal function in ERM.


Asunto(s)
Membrana Epirretinal , Membrana Basal/cirugía , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/cirugía , Humanos , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía
7.
Sci Rep ; 11(1): 4583, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33633268

RESUMEN

We non-invasively evaluated macular non-perfused areas (m-NPAs) of branch retinal vein occlusion (BRVO) using optical coherence tomography (OCT) angiography and the Humphrey visual field analyser 10-2 programme (HFA 10-2). We enrolled 30 patients (30 eyes) with macular oedema secondary to BRVO. OCT angiography was used to photograph the macula at 6 × 6-mm; sizes of m-NPAs in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were measured in four areas. For HFA 10-2, we divided the actual measurement threshold of 68 points into four areas and calculated the mean central visual field sensitivity (CVFS). The correlation between the mean m-NPA and mean CVFS (dB) in each area was examined. There was a strong correlation between the m-NPA of each region detected in SCP and DCP, and the mean CVFS of each corresponding area (SCP: r = - 0.83, r = - 0.64, r = - 0.73, and r = - 0.79; DCP: r = - 0.82, r = - 0.71, r = - 0.71, and r = - 0.70), p values were < 0.001 for all. m-NPAs were associated with decreased visual field sensitivity in BRVO. Non-invasive m-NPA evaluation was possible using OCT angiography and HFA 10-2.


Asunto(s)
Angiografía/métodos , Capilares/fisiopatología , Oclusión de la Vena Retiniana/diagnóstico por imagen , Vasos Retinianos/fisiopatología , Tomografía de Coherencia Óptica/métodos , Pruebas del Campo Visual/instrumentación , Anciano , Femenino , Humanos , Edema Macular/complicaciones , Edema Macular/fisiopatología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Oclusión de la Vena Retiniana/complicaciones , Oclusión de la Vena Retiniana/fisiopatología
8.
BMJ Open Ophthalmol ; 5(1): e000636, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33376808

RESUMEN

OBJECTIVE: To investigate the relationship between the preoperative morphology of the foveal avascular zone (FAZ) and postoperative visual function in patients with idiopathic epiretinal membrane (ERM). METHODS AND ANALYSIS: This retrospective study enrolled 36 patients who underwent a unilateral internal limiting membrane peeling with vitrectomy for idiopathic ERM. We measured the area of superficial FAZ in the eyes with ERM and in the contralateral control eyes preoperatively and at 6 months postoperatively using optical coherence tomography (OCT) angiography. The ERM stage was measured using swept-source OCT. We evaluated the FAZ area ratio (preoperative FAZ of the ERM eye/FAZ of the control eye) to indicate the degree of FAZ contraction in the ERM eyes compared with the control eyes. The correlations between the FAZ area ratio and postoperative visual function and changes in macular morphology were assessed. RESULTS: Preoperative mean best-corrected visual acuity (BCVA) significantly improved from the logarithm of the minimum angle of resolution 0.20±0.24 to 0.01±0.13 at 6 months postoperatively (p<0.01). The mean area of the FAZ increased significantly from 0.06±0.07 mm2 preoperatively to 0.09±0.07 mm2 after vitrectomy (p<0.01). FAZ area ratio showed significant negative correlations with changes in BCVA (r=-0.44, p<0.01) and the ERM stages (r=-0.56, p<0.01). CONCLUSION: The FAZ is reduced as ERM progresses and enlarges after vitrectomy. The FAZ area ratio based on preoperative FAZ may predict postoperative visual acuity.

9.
Biosci Biotechnol Biochem ; 74(12): 2405-12, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21150124

RESUMEN

We succeeded in the purification and gene cloning of a new enzyme, α-methyl carboxylic acid deracemizing enzyme 1 (MCAD1) from Brevibacterium ketoglutamicum KU1073, which catalyzes the (S)-enantioselective thioesterification reaction of 2-(4-chlorophenoxy)propanoic acid (CPPA). The cloned gene of MCAD1 contained an ORF of 1,623 bp, encoding a polypeptide of 540 amino acids. In combination with cofactors ATP, coenzyme A (CoASH), and Mg(2+), MCAD1 demonstrated perfect enantioselectivity toward CPPA. The optimal pH and temperature for reaction were found to be 7.25 and 30 °C. Under these conditions, the K(m) and k(cat) values for (S)-CPPA were 0.92 ± 0.17 mM and 0.28 ± 0.026 s(-1) respectively. The results for substrate specificity revealed that MCAD1 had highest activity toward fatty acid tails with a medium chain-length (C(8)). This result indicates that MCAD1 should be classified into a family of medium-chain acyl-CoA synthetase. This novel activity has never been reported for this family.


Asunto(s)
Ácido 2-Metil-4-clorofenoxiacético/análogos & derivados , Brevibacterium/enzimología , Coenzima A Ligasas/genética , Coenzima A Ligasas/aislamiento & purificación , Fenilpropionatos/química , Fenilpropionatos/metabolismo , Ácido 2-Metil-4-clorofenoxiacético/química , Ácido 2-Metil-4-clorofenoxiacético/metabolismo , Secuencia de Aminoácidos , Brevibacterium/genética , Brevibacterium/metabolismo , Sistema Libre de Células/enzimología , Clonación Molecular , Coenzima A Ligasas/química , Coenzima A Ligasas/metabolismo , Estabilidad de Enzimas , Esterificación , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Análisis de Secuencia de ADN , Estereoisomerismo , Especificidad por Sustrato
10.
FEBS J ; 274(15): 3877-85, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17617223

RESUMEN

We introduce a new application of firefly luciferase (EC 1.13.12.7). The firefly luciferases belong to a large superfamily that includes rat liver long-chain acyl-CoA synthetase (LACS1). LACS1 is the enzyme that is involved in the deracemization process of 2-arylpropanoic acid and catalyzes the enantioselective thioester formation of R-acids. Based on the similarity of the reaction mechanisms and the sequences between firefly luciferase and LACS1, we predicted that firefly luciferase also has thioesterification activity toward 2-arylpropanoic acid. From an investigation using three kinds of luciferases from North American firefly and Japanese fireflies, we have confirmed that these luciferases exhibit an enantioselective thioester formation activity and the R-form is transformed to a thioester in preference to the S-form in the presence of ATP, Mg(2+), and CoASH. The enantiomeric excesses of unreacted recovered acid and thioester were determined by chiral phase HPLC analysis and the resulting 2-arylpropanoyl-CoAs were identified by high resolution mass spectroscopy. The K(m) and k(cat) values of thermostable luciferase from Luciola lateralis (LUC-H) toward ketoprofen were determined as 0.22 mM and 0.11 s(-1), respectively. The affinity of ketoprofen was almost the same of d-luciferin. In addition, the calculated E-value toward ketoprofen was approximately 20. These results suggest that LUC-H could catalyze the kinetic resolution of 2-arylpropanoic acid efficiently and would be a new option for the preparation of optically active 2-substituted carboxylic acids.


Asunto(s)
Ésteres/química , Ésteres/metabolismo , Luciferasas de Luciérnaga/metabolismo , Propionatos/química , Propionatos/metabolismo , Compuestos de Sulfhidrilo/química , Animales , Catálisis , Luciérnagas/enzimología , Concentración de Iones de Hidrógeno , Cinética , Luciferasas de Luciérnaga/genética , Espectrometría de Masas , Estructura Molecular , Estereoisomerismo , Especificidad por Sustrato
11.
Eur J Pharm Biopharm ; 59(1): 25-33, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15567298

RESUMEN

FK888 is a candidate selective NK1 receptor antagonist, and it exhibits poor absorption from the gastrointestinal tract in healthy volunteers. In a previous study, the optimized dry powder inhaler (DPI) formulation with carrier lactose using the Spinhaler was developed, although the maximum dose per capsule was only 5mg because the fine particle fraction (FPF) was reduced at doses over 5mg. The objective of this study was to develop an optimized DPI formulation for higher doses, such as 40 mg, with proportional systemic absorption. The Spinhaler and E-haler were used as the inhalation devices, and the in vitro deposition was evaluated using a multistage cascade impactor at different flow rates (28.3 and 60 l/min). When hydroxypropyl methylcellulose (HPMC) capsules were used as the container, and spherical soft agglomerates of fine FK888 particles (soft pellets) and the E-haler were used, the fraction of particles emitted from the inhalation system (Em) was significantly improved, to over 80% of the nominal dose, and no significant difference was found between the airflow rates (84.3+/-2.3% for 28.3 l/min, 88.1+/-3.6% for 60 l/min). It was also found that the E-haler was an extremely suitable device for obtaining the higher respirable particle percentage of emitted particles (RP) in the 40 mg formulation with the soft pellets contained in HPMC capsules (35.0+/-1.8% for 28.3 l/min and 42.5+/-3.5% for 60 l/min), compared with the Spinhaler (13.8+/-3.0% for 28.3 l/min and 28.9+/-1.0% for 60 l/min). Using the formulations with the E-haler, proportional systemic absorption was achieved up to 40 mg FK888 in healthy volunteers (62.91+/-27.58, 103.70+/-40.19 and 254.79+/-85.01 ngh/ml as AUCs for 10, 20 and 40 mg FK888, respectively; R(2)=0.9641). It is also expected that the E-haler will act as an efficient device when a higher dose, such as 40 mg, is required in clinical situations.


Asunto(s)
Dipéptidos/administración & dosificación , Dipéptidos/química , Indoles/administración & dosificación , Indoles/química , Inhaladores de Dosis Medida/normas , Absorción/efectos de los fármacos , Absorción/fisiología , Administración por Inhalación , Adulto , Química Farmacéutica , Humanos , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Polvos
12.
J Control Release ; 97(1): 19-29, 2004 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-15147801

RESUMEN

(4R)-4-Hydroxy-l-[(l-methyl-lH-indol-3-yl)carbonyl]-L-prolyl-N-benzyl-N-methyl-3-(2-naphthyl)-L-alaninamide (FK888) is a candidate selective NK1 receptor antagonist, and it exhibits poor absorption from the gastrointestinal (GI) tract in healthy volunteers. The objective of this study was to develop an optimized DPI formulation with carrier lactose using a Spinhaler, and thereby improve the systemic absorption of FK888. The fine particles of FK888 were blended with various carrier lactoses, and in vitro deposition properties were investigated using a twin impinger. The mixture using 100 M and 325 M lactoses [Sieved lactoses (SLs)] exhibited a higher emitted dose (Em) than 200 M, 450 M and micronized lactoses [Milled lactoses (MLs)]. The flowability of carrier lactose had an influence on the Em. On the other hand, the respirable particle (RP) fraction in the formulations with MLs was much higher than that of SLs, in spite of the blended ratios of lactose. It was also observed that the mixture of 325 M with the micronized lactose particles had the same RP as 200 M, although the 325 M alone had a low RP. Considering the Em and RP obtained, we chose 200 M for FK888 dry powder inhaler (DPI). The proportional absorption was found up to the 12.5% of the FK888 ratio (5 mg as unit dose) for the Cmax and AUC in healthy volunteers. In conclusion, 200 M, which has fine lactose particles and a better flowability than other MLs, is an extremely suitable carrier for maximizing the fine particle dose as far as FK888 is concerned. Furthermore, an improvement in the systemic absorption of FK888 was achieved using the dry powder formulations.


Asunto(s)
Dipéptidos/administración & dosificación , Portadores de Fármacos/administración & dosificación , Indoles/administración & dosificación , Lactosa/administración & dosificación , Inhaladores de Dosis Medida , Absorción/efectos de los fármacos , Absorción/fisiología , Administración por Inhalación , Adulto , Química Farmacéutica , Dipéptidos/farmacocinética , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/farmacocinética , Humanos , Indoles/farmacocinética , Lactosa/farmacocinética , Masculino , Inhaladores de Dosis Medida/estadística & datos numéricos , Polvos
13.
Eur J Pharm Biopharm ; 56(3): 319-25, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14602173

RESUMEN

FK224 is a cyclopeptide drug with poor oral absorption due to proteolysis in the gastrointestinal tract. The objectives of this study were to investigate the absorption of FK224 from the lung in healthy volunteers, and compare the pharmacokinetic profiles of FK224 after inhalation from a pressurized metered dose inhaler (pMDI) and dry powder inhaler (DPI). The pMDI (Suspension type, 1 mg as FK224/puff) and DPI (4 mg and 10 mg as FK224/capsule, using Spinhaler as the device) were developed by formulating the same micronized particles of FK224 which were premixed with beta-cyclodextrin (beta-CyD) to improve the solubility of FK224. In the case of pMDI, 1, 4 or 8 mg was inhaled by the corresponding number of puffs with the pMDI. In addition, the in vitro drug delivery characteristics of the inhalers were evaluated using a multistage liquid impinger. In both inhalers, it was observed that FK224 could be absorbed into the systemic circulation from the lungs of the healthy volunteers, and the AUC and C(max) were proportionally increased depending on the emitted dose after inhalation. However, the pharmacokinetic (PK) parameters for DPI were significantly higher than that of pMDI, in spite of usage of the same fine particles for the formulations in both inhalers. Based on the distribution from the in vitro examination, the fine particle dose, which is defined as the dose region delivered as particles <3.8 microm, was calculated from the emitted dose inhaled by the healthy volunteers. It was found that the PK parameters for both inhalers were proportionally increased depending on the predicted fine particle dose regardless of the type of inhaler. This suggests that the absorption from the lung is influenced by the fine particle dose. We concluded that DPI is a suitable inhaler for FK224, and the alveolus, which is generally known as the site of action of the fine particles, is a possible absorptive site for FK224.


Asunto(s)
Pulmón/metabolismo , Péptidos Cíclicos/administración & dosificación , Péptidos Cíclicos/farmacocinética , Administración por Inhalación , Adulto , Relación Dosis-Respuesta a Droga , Humanos , Pulmón/efectos de los fármacos , Masculino , Inhaladores de Dosis Medida , Persona de Mediana Edad , Tamaño de la Partícula , Polvos
14.
Eur J Pharm Biopharm ; 55(2): 147-54, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12637090

RESUMEN

FK224 is a cyclopeptide drug with a low aqueous solubility. Following oral administration to rats, poor absorption was observed due to proteolysis in the gastrointestinal tract. The objective of this study was to investigate the effect of the pulmonary route on the systemic absorption of FK224 in comparison with other administration routes, and to determine the bioavailability (BA) of FK224 following pulmonary administration in rats using various dosage forms. From absorption studies on the Polyethylene Glycol 400 solution given by various routes (intranasal, subcutaneous, intratracheal and intravenous as reference), it was shown that pulmonary administration was a potentially attractive route for FK224. In the pulmonary absorption studies, after administration of the aqueous suspension, the BA was reduced to 2.7% compared with 16.8% for the solution. However, beta-cyclodextrin (beta-CyD) was found to be an effective additive as far as improving the solubility of FK224 was concerned. The BA of the aqueous suspension containing beta-CyD was increased to 19.2%. Pressurized metered dose inhalers were prepared by formulating beta-CyD with various molar ratios of 1:0, 1:1 and 1:7 (FK224/beta-CyD), and the resulting BAs were 4.3%, 29.0% and 91.2%, respectively. It was observed that both the C(max) and AUC of FK224 were increased as the amount of beta-CyD increased. The plasma profiles showed sustained absorption. In conclusion, we have seen that the lung is a suitable route for absorption of FK224, and beta-CyD is an extremely effective additive as far as improving the pulmonary absorption of FK224 is concerned. beta-CyD or derivatives with various degrees of aqueous solubility are potential drug carriers for controlling pulmonary absorption.


Asunto(s)
Ciclodextrinas/química , Excipientes/química , Pulmón/metabolismo , Péptidos Cíclicos/farmacocinética , beta-Ciclodextrinas , Absorción , Administración Intranasal , Administración Oral , Animales , Área Bajo la Curva , Disponibilidad Biológica , Química Farmacéutica , Inyecciones Subcutáneas , Cininas/antagonistas & inhibidores , Masculino , Tamaño de la Partícula , Péptidos Cíclicos/administración & dosificación , Péptidos Cíclicos/química , Soluciones Farmacéuticas , Ratas , Ratas Sprague-Dawley , Solubilidad , Sustancia P/agonistas , Suspensiones , Factores de Tiempo
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