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BACKGROUND/AIM: Fucoxanthin (Fx), a dietary marine xanthophyll, exerts potent anticancer effects in various colorectal cancer (CRC) animal models. However, therapeutic effects of Fx in human cancer tissues remain unclear. A patient-derived xenograft (PDX) mouse model transplanted with cancer tissues from patients is widely accepted as the best preclinical model for evaluating the anticancer potential of drug candidates. MATERIALS AND METHODS: Herein, we investigated the anticancer effects of Fx in PDX mice transplanted with cancer tissues derived from a patient with CRC (CRC-PDX) using LC-MS/MS- and western blot-based proteome analysis. RESULTS: The tumor in the patient with CRC was a primary adenocarcinoma (T3N0M0, stage II) showing mutations of certain genes that were tumor protein p53 (TP53), AT-rich interaction domain 1A (ARID1A), neuroblastoma RAS viral oncogene homolog (NRAS), and PMS1 homolog 2 (PMS2). Administration of Fx significantly suppressed the tumor growth (0.6-fold) and tended to induce differentiation in CRC-PDX mice. Fx up-regulated glycanated-decorin (Gc-DCN) expression, and down-regulated Kinetochore-associated protein DSN1 homolog (DSN1), phospho(p) focal adhesion kinase (pFAK)(Tyr397), pPaxillin(Tyr31), and c-MYC involved in growth, adhesion, and/or cell cycle, in the tumors of CRC-PDX mice than in control mice. Alterations in the five proteins were consistent with those in human CRC HT-29 and HCT116 cells treated with fucoxanthinol (FxOH, a major metabolite of Fx). CONCLUSION: Fx suppresses development of human-like CRC tissues, especially through growth, adhesion, and cell cycle signals.
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Neoplasias Colorrectales , Humanos , Animales , Ratones , Cromatografía Liquida , Neoplasias Colorrectales/genética , Espectrometría de Masas en Tándem , Ciclo Celular , Xantófilas/farmacología , Xantófilas/uso terapéutico , Modelos Animales de Enfermedad , Proteínas Cromosómicas no HistonaRESUMEN
Reportedly, a relationship exists between intestinal microflora and obesity-related lifestyle diseases. Blautia spp. a major intestinal microbiota, accounts for 3-11% of human intestinal microflora. Epidemiological reports have described that people with more visceral fat have less Blautia hansenii in their intestinal tract irrespective of age or gender. However, the effect of oral administration of heat-sterilized Blautia hansenii on obesity has not been clarified. Therefore, the aim of this study was to evaluate the effects of dietary Blautia hansenii administration on obesity in high-fat-diet-induced obesity in a mouse model. Heat-sterilized cells of Blautia hansenii were used. C57BL/6J mice (normal mice, n = 7) were fed with each experimental diet for nine weeks. Diets for experimentation were: normal-fat (NF) diets, high-fat (HF) diets, and high-fat + Blautia hansenii (HF + Blautia) diets. The HF + Blautia group was administered about 1 × 109 (CFU/mouse/day) of Blautia hansenii. During the periods of experimentation, body weight, food intake, water consumption, and fecal weight were recorded, and glucose tolerance tests were performed. Subsequently, the white adipose tissue (WAT) weight and serum components were measured. Short-chain fatty acid contents in the feces and cecum were analyzed. Furthermore, changes in the intestinal microflora were analyzed using meta-genomics analysis. Results showed that the total weight of WAT in the HF + Blautia group was significantly lower (13.2%) than that of the HF group. Moreover, the HF + Blautia group exhibited better glucose tolerance than the HF group. Productivity of short-chain fatty acids in the intestinal tract was at a significantly (p < 0.05) low level in the HF group; on the other hand, it recovered in the HF + Blautia group. Furthermore, there was a higher ratio of Blautia (p < 0.05) in the intestinal tracts of the HF + Blautia group than in the HF group. These results suggest that Blautia hansenii administration suppresses obesity induced by a high-fat diet.
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Metamorphopsia is an important visual symptom of macular disease. We determined predictors for metamorphopsia investigating the relationships of macular hole (MH) diameter and retinal layer thicknesses with metamorphopsia after MH surgery. Forty-two eyes of 42 consecutive patients undergoing MH surgery were retrospectively studied. Metamorphopsia was measured with M-CHARTS. Inner nuclear layer (INL) and outer retinal layer (OR) thicknesses were measured 1000 µm away from central fovea at using Spectralis. Preoperative M-CHARTS scores correlated with MH diameters (P = 0.007-0.031) and changes of temporal OR thickness (P = 0.008-0.010). Postoperative M-CHARTS score at 3 months correlated with preoperative nasal and inferior OR thicknesses (P = 0.003 and 0.016) and with changes of superior INL at 3 and 6 months (P = 0.011 and 0.025), and score at 1 month with change of temporal OR at 6 months (P = 0.033). Postoperative improvement of M-CHARTS scores correlated with changes of temporal INL and superior OR (P = 0.026 and 0.002). Multiple regression analysis revealed that MH diameter was a significant predictor for metamorphopsia. Photoreceptor displacement and inner retinal change may generate metamorphopsia in MH undergoing surgery, however MH diameter is the most powerful predictor.
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Perforaciones de la Retina , Humanos , Perforaciones de la Retina/cirugía , Estudios Retrospectivos , Agudeza Visual , Vitrectomía/efectos adversos , Tomografía de Coherencia Óptica , Trastornos de la Visión/diagnósticoRESUMEN
PURPOSE: To evaluate the outer retinal microstructure and visual function after idiopathic macular hole (MH) surgery using internal limiting membrane (ILM) peeling with and without Brilliant Blue G (BBG) staining. STUDY DESIGN: Retrospective, consecutive case series. METHODS: A total of 49 eyes of 47 patients were enrolled: 23 eyes of 23 patients with MH who underwent ILM peeling without dyes (control group) and 26 eyes of 26 patients who underwent BBG staining (BBG group). The lengths of defects of the photoreceptor ellipsoid zone (EZ), external limiting membrane (ELM), and interdigitation zone (IZ) were measured. RESULTS: The rate of MH closure after initial surgery was 95.6% (22/23 eyes) for the control group versus 100% (26/26 eyes) for the BBG group. In the 48 eyes with MH closure, the recovery rate of ELM deficiency and change in IZ deficiency showed no difference between the groups. The changes in EZ deficiency at 1 and 12 months were greater in the BBG group than in the control group. (P = 0.047 and 0.031). Visual acuity was better in the BBG group than in the control group during 12 months postoperatively (P < 0.001-0.038). CONCLUSION: Eyes undergoing BBG-assisted MH surgery achieved faster recovery of the outer retinal structures and greater visual improvement than those of eyes without BBG.
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Perforaciones de la Retina , Humanos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Vitrectomía , Estudios Retrospectivos , Colorantes de Rosanilina , Membrana Basal/cirugía , Tomografía de Coherencia ÓpticaRESUMEN
PURPOSE: To examine 1-year outcomes of metamorphopsia and tangential retinal displacement after epiretinal membrane surgery and identify predictors for metamorphopsia score at 1 year and its improvement from baseline. METHODS: M-CHARTS were used to measure metamorphopsia. Distances between the intersections of two sets of retinal vessels were measured with infrared or autofluorescence images. Predictors for metamorphopsia scores at 1 year after surgery and their differences from baseline were identified with multivariate regression analysis. RESULTS: Ninety-two eyes of 90 consecutive patients were included. The vertical and horizontal distances continued expanding for 1 year ( P < 0.001). Both vertical and horizontal metamorphopsia scores improved 3 months after surgery ( P = 0.025 and P < 0.001, respectively), and horizontal scores continued improving for a year. Horizontal metamorphopsia scores correlated with retinal displacement more strongly than vertical scores. Higher metamorphopsia score at baseline is predictive for that at 1 year. Older age and being male are predictive for less improvement of the score at 1 year from baseline. CONCLUSION: Metamorphopsia correlates with tangential retinal displacement at 1 year after epiretinal membrane surgery. Horizontal metamorphopsia scores keep improving until 1 year postoperatively. Being male and older age are both independent predictors for poor improvement of metamorphopsia after epiretinal membrane surgery.
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Membrana Epirretinal , Membrana Epirretinal/cirugía , Femenino , Humanos , Masculino , Retina , Tomografía de Coherencia Óptica/métodos , Trastornos de la Visión/etiología , Trastornos de la Visión/cirugía , Agudeza Visual , VitrectomíaRESUMEN
PURPOSE: To investigate the correlations of thickness of three retinal layers with retinal displacement after idiopathic macular hole surgery. STUDY DESIGN: Retrospective, consecutive, case series. METHODS: 42 eyes of 42 patients undergoing macular hole surgery with internal limiting membrane peeling were studied. Retinal distance was measured with near-infrared images between the optic nerve and the intersection of retinal vessels at four quadrants. Retinal thicknesses of inner retinal layer, inner nuclear layer and outer retinal layer were measured 1000 µm away from the central fovea using Spectralis. RESULTS: Retinal distances other than the nasal quadrant decreased postoperatively (p < 0.001). Retinal displacement (%) correlated significantly with the change in inner nuclear layer thickness in the temporal sector at 1, 3, and 6 months, in the superior sector at 2 weeks, 1, and 6 months, and in the inferior sector at 3 and 6 months postoperatively (r = 0.319-0.570, p < 0.001-0.040), but not in the inner or outer retinal layers. CONCLUSION: Internal limiting membrane peeling for macular hole enhances retinal displacement toward the optic disc, whose distances correlate with the changes in inner nuclear layer thickness.
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Membrana Epirretinal , Perforaciones de la Retina , Membrana Epirretinal/cirugía , Humanos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Vitrectomía/métodosRESUMEN
PURPOSE: Vital dyes are frequently used to visualize the internal limiting membrane (ILM) of the neuroretina. This study evaluated and compared the microstructure of the inner retina and visual function with and without brilliant blue G (BBG) staining for ILM peeling during idiopathic epiretinal membrane (ERM) surgery. STUDY DESIGN: Retrospective, consecutive, interventional case series. METHODS: Fifty-five patients (55 eyes) with ERM underwent ILM peeling without dyes (non-dye group) and 55 patients (55 eyes) underwent ILM peeling with BBG staining (BBG group). The logMAR visual acuity (VA) and ganglion cell complex (GCC) thickness were measured using optical coherence tomography at baseline and 12 months after surgery. RESULTS: LogMAR VA improved significantly in both groups at 12 months and the BBG group tended to be better than the non-dye group but with no significant difference between the groups (unpaired t-test, P = 0.490). The average GCC thickness significantly decreased in both groups; however, there was no difference in the rates of change in GCC thickness between the groups. The ratio of GCC thickness to total retinal thickness (%) was significantly higher in the BBG group in the superior quadrant at 12 months postoperatively (P = 0.010). CONCLUSION: BBG-assisted ERM surgery resulted in better visual improvement and fewer structural changes in the inner retinal layers. BBG-assisted ILM peeling is safe both functionally and anatomically.
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Membrana Epirretinal , Membrana Basal/cirugía , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/cirugía , Humanos , Retina/diagnóstico por imagen , Estudios Retrospectivos , Colorantes de Rosanilina , Tomografía de Coherencia Óptica , VitrectomíaRESUMEN
INTRODUCTION: The purpose of this prospective cohort study was to investigate the prevalence and burden of "any physical complaint" in college female basketball athletes using a daily questionnaire. METHODS: Fifty-four female college basketball players were recruited and followed up for 135 days using the Oslo Sports Trauma Research Centre questionnaire. RESULTS: The questionnaire response rate was 96.4% (95% confidence interval: 95.7-97.1). The average daily prevalence of any problem was 44.4%, whereas that of substantial problems was 16.0%. The anatomical areas found to be most frequently affected by physical problems were the ankle (average daily prevalence: 14.5%, 95% confidence interval: 13.4-15.7), lower back (14.4%, 95% confidence interval: 13.7-15.2), and knee (9.6%, 95% confidence interval: 9.0-10.2). The cumulative severity score, calculated by summing severity scores and dividing by number of respondents, showed that ankle, knee, and lower back problems exhibited greater relative burden. DISCUSSION: Injuries common in basketball athletes, such as ankle sprain, anterior cruciate ligament injury, overuse knee pain, and low-back pain, are reflected in the present data.
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PURPOSE: To determine the relationship between the subfoveal choroidal thickness (SCT) and intraocular pressure (IOP) following 25-gauge (25G) and 23-gauge (23G) vitrectomy for idiopathic epiretinal membrane (ERM). STUDY DESIGN: Retrospective, consecutive, interventional case series. METHODS: Sixty-two patients undergoing 25G vitrectomy and 56 patients undergoing 23G vitrectomy for ERM participated. SCT was measured using enhanced depth imaging optical coherence tomography and IOP were measured both at baseline and postoperatively. RESULTS: In both groups, the IOPs on day one and one week after surgery were significantly lower than at baseline (P < 0.001 for both). The rates of changes of IOP were significantly greater in 23G compared to 25G on day one (P = 0.026). In 23G the SCTs on day one and one week after surgery were significantly thicker (P < 0.001) than baseline. The rates of changes in SCT between baseline and day one negatively correlated with those of IOP in 23G (r = -0.559, P < 0.001) but no correlation was observed with 25G (r = -0.129, P = 0.316). CONCLUSION: Choroidal thickness increases soon after 23G vitrectomy for ERM which is probably due to the transient hypotony, however, early SCT change does not appear in 25G vitrectomy. Twenty-five-gauge vitrectomy may have an advantage in minimizing postoperative choroidal changes.
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Coroides/patología , Membrana Epirretinal/cirugía , Presión Intraocular/fisiología , Vitrectomía , Anciano , Anciano de 80 o más Años , Coroides/diagnóstico por imagen , Membrana Epirretinal/fisiopatología , Femenino , Fóvea Central , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Tonometría Ocular , Agudeza Visual/fisiologíaRESUMEN
PURPOSE: To compare latanoprost/timolol (LT) versus travoprost/timolol (TT) fixed combinations for ocular hypertension (OHT) associated with uveitis. METHODS: Thirty-six patients (55 eyes) who were treated with LT (28 eyes) or TT (27 eyes) for OHT associated with uveitis were reviewed retrospectively. Intraocular pressure (IOP) and inflammation scores at the initiation of treatment and at the last visit during therapy were analyzed. RESULTS: Although IOP was reduced significantly in both LT and TT groups, the reduction rate was significantly greater with TT group than with LT. The differences in the reduction of IOP between the groups remained significant when the cases were classified into inflammation-induced OHT and steroid-induced OHT. Inflammation score was not exacerbated by LT or TT treatment. CONCLUSIONS: Both LT and TT are safe and effective for the treatment of OHT associated with uveitis and greater IOP reduction may be achieved by TT than by LT treatment.
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Antihipertensivos/uso terapéutico , Presión Intraocular/efectos de los fármacos , Hipertensión Ocular/tratamiento farmacológico , Prostaglandinas F Sintéticas/uso terapéutico , Timolol/uso terapéutico , Travoprost/uso terapéutico , Uveítis/tratamiento farmacológico , Antihipertensivos/administración & dosificación , Combinación de Medicamentos , Femenino , Humanos , Latanoprost , Masculino , Persona de Mediana Edad , Hipertensión Ocular/etiología , Soluciones Oftálmicas , Prostaglandinas F Sintéticas/efectos adversos , Estudios Retrospectivos , Timolol/efectos adversos , Tonometría Ocular , Travoprost/efectos adversos , Resultado del Tratamiento , Uveítis/complicacionesRESUMEN
PURPOSE: To examine antigen-stimulated cytokine production by Behçet disease patients (BD) before and after infliximab infusion. METHODS: PBMCs were obtained before and after infliximab infusion in BD patients with or without recurrent uveitis during at least 1 year of infliximab therapy, and from healthy subjects. PBMCs were cultured with IRBP, and Th-related cytokines in cultures were measured. RESULTS: Levels of IL-4, IL-6, IL-10 IL-17A, IL-17F, IL-31, IFN-γ, and TNFα were higher in BD before infliximab infusion than in healthy subjects, and these levels were the highest in BD with recurrent uveitis. After infliximab infusion, these cytokine levels were reduced to a greater extent in BD without recurrent uveitis than in BD with recurrence. CONCLUSIONS: Th-related cytokines produced by IRBP-stimulated PBMCs were elevated in BD, and infliximab infusion suppressed these cytokines to a greater extent in BD without recurrent uveitis than in those with recurrence.
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Síndrome de Behçet/tratamiento farmacológico , Citocinas/metabolismo , Inmunosupresores/uso terapéutico , Infliximab/uso terapéutico , Linfocitos T Colaboradores-Inductores/inmunología , Uveítis/tratamiento farmacológico , Adulto , Síndrome de Behçet/inmunología , Proteínas del Ojo/farmacología , Femenino , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proteínas de Unión al Retinol/farmacología , Uveítis/inmunologíaRESUMEN
PURPOSE: To investigate helper T (Th) cell-related cytokines elevated in the vitreous of endogenous uveitis (EU), and to compare these with those of acute retinal necrosis (ARN). METHODS: Vitreous fluids were obtained from 23 eyes of EU patients, 4 eyes of ARN patients, and 14 eyes of patients with epiretinal membrane (ERM) who had had vitrectomy surgery. The vitreous levels of interleukin (IL)-1, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon (IFN)-γ, soluble CD40 ligand (sCD40L) and tumor necrosis factor (TNF)-α were measured. RESULTS: The vitreous cytokine levels of IL-6, IL-10, IL-31, IFN-γ and TNF-α in the EU patients were significantly higher than in the ERM patients. On the other hand, the levels of IL-1ß, IL-6, IL-10, IL-31, IFN-γ, sCD40L and TNF-α were significantly higher in the ARN patients than in the EU patients, while those of IL-4, IL-17A and IL-22 were higher in the EU patients than in the ARN patients although they were not significant. CONCLUSIONS: It is suggested that Th1-, Th2- and Th17 cells are related to the development of EU, and Th1- and regulatory T cells to that of ARN, and that the severity of ocular inflammation may be associated with the activity of Th1 cells.
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Citocinas/análisis , Linfocitos T Colaboradores-Inductores , Linfocitos T Reguladores , Uveítis/inmunología , Cuerpo Vítreo/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Necrosis Retiniana Aguda/inmunologíaRESUMEN
Proliferation-differentiation balance of epithelial cells is regulated by Krüppel-like factors (KLF) 4 and 5, and the unbalanced expression relates to carcinoma progression. However, little is known about the expression and role in oral carcinomas. This study examined expression of KLF4 and KLF 5 in the carcinomas by immunohistochemistry (n = 67) and the involvement in proliferation and differentiation of carcinoma cells. KLF4 was detected in keratinizing carcinoma cells and KLF5 in non-keratinizing cells. KLF4 staining declined in the patient with lymph node metastasis (P < 0.05) and in parallel with the histological dedifferentiation (P = 0.09). Exogenous overexpression of KLF4 arranged cells in a cobble-like structure with desmosomes and KLF5 elongated cells like fibroblasts without desmosomes. KLF4 suppressed fibronectin expression, and KLF5 down-regulated and degraded E-cadherin. The proliferation was not affected by KLFs. Thus, down-regulation of KLF4 and up-regulation of KLF5 may stimulate oral carcinoma progression through the dedifferentiation of carcinoma cells.
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Carcinoma/metabolismo , Desdiferenciación Celular/genética , Diferenciación Celular/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Neoplasias de la Boca/metabolismo , Anciano , Cadherinas/metabolismo , Carcinoma/genética , Carcinoma/patología , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Femenino , Humanos , Factor 4 Similar a Kruppel , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Regulación hacia ArribaRESUMEN
AIMS: To evaluate the prevalence and aetiology of intraocular hypertension (OHT) in granulomatous and non-granulomatous uveitis METHODS: Medical records of 304 consecutive patients (484 eyes) with uveitis who visited the National Defense Medical Collage Hospital between April 2010 and March 2013 were reviewed retrospectively. OHT irrelevant to glaucomatous changes in optic disc or visual field was investigated. RESULTS: OHT was found in 123 eyes (25.4%) of 93 uveitic patients (30.6%); 92% of the eyes had open-angle OHT, 45.6% of which was steroid-induced. The prevalence of OHT was 100% (8/8) in Posner-Schlossman syndrome, 50.0% (10/20) in varicella zoster virus-associated iridocyclitis, 45% (9/20) in scleritis, 34.1% (15/44) in Vogt-Koyanagi-Harada disease, 32.1% (18/56) in Behçet's disease (BD), 23.1% (6/26) in acute anterior uveitis, and 20.2% (19/94) in sarcoidosis. Pupillary block was observed only in non-granulomatous uveitis, but not in granulomatous uveitis. Seventy percent of OHT in granulomatous uveitis cases was inflammation-induced, while 76.7% in non-granulomatous uveitis cases was steroid-induced. CONCLUSIONS: OHT in non-granulomatous uveitis was mainly steroid-induced open-angle OHT with some cases of angle-closure OHT caused by pupillary block, while that in granulomatous uveitis was mostly inflammation-induced open-angle OHT with no pupillary block-related angle-closure OHT.
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Hipertensión Ocular/epidemiología , Hipertensión Ocular/etiología , Uveítis/epidemiología , Uveítis/etiología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Presión Intraocular , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Distribución por Sexo , Uveítis/clasificación , Adulto JovenRESUMEN
PURPOSE: To design a high drug loading formulation of self-microemulsifying/micelle system. METHODS: A poorly-soluble model drug (CH5137291), 8 hydrophilic surfactants (HS), 10 lipophilic surfactants (LS), 5 oils, and PEG400 were used. A high loading formulation was designed by a following stepwise approach using a high-throughput formulation screening (HTFS) system: (1) an oil/solvent was selected by solubility of the drug; (2) a suitable HS for highly loading was selected by the screenings of emulsion/micelle size and phase stability in binary systems (HS, oil/solvent) with increasing loading levels; (3) a LS that formed a broad SMEDDS/micelle area on a phase diagram containing the HS and oil/solvent was selected by the same screenings; (4) an optimized formulation was selected by evaluating the loading capacity of the crystalline drug. Aqueous solubility behavior and oral absorption (Beagle dog) of the optimized formulation were compared with conventional formulations (jet-milled, PEG400). RESULTS: As an optimized formulation, d-α-tocopheryl polyoxyethylene 1000 succinic ester: PEG400 = 8:2 was selected, and achieved the target loading level (200 mg/mL). The formulation formed fine emulsion/micelle (49.1 nm), and generated and maintained a supersaturated state at a higher level compared with the conventional formulations. In the oral absorption test, the area under the plasma concentration-time curve of the optimized formulation was 16.5-fold higher than that of the jet-milled formulation. CONCLUSIONS: The high loading formulation designed by the stepwise approach using the HTFS system improved the oral absorption of the poorly-soluble model drug.
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Química Farmacéutica/métodos , Emulsiones/química , Micelas , Preparaciones Farmacéuticas/química , Absorción , Animales , Cristalinas/química , Perros , Aceites/química , Tamaño de la Partícula , Preparaciones Farmacéuticas/administración & dosificación , Polietilenglicoles/química , Solubilidad , Solventes/química , Tensoactivos/química , Agua/químicaRESUMEN
Methane (CH(4)) is the second most important greenhouse gas (GHG) and that emitted from enteric fermentation in livestock is the single largest source of emissions in Japan. Many factors influence ruminant CH(4) production, including level of intake, type and quality of feeds and environmental temperature. The objectives of this review are to identify the factors affecting CH(4) production in ruminants, to examine technologies for the mitigation of CH(4) emissions from ruminants, and to identify areas requiring further research. The following equation for CH(4) prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = -17.766 + 42.793X - 0.849X(2), where Y is CH(4) production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH(4) emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH(4) inhibitors, and defaunation. Considering the importance of ruminant livestock, it is essential to establish economically feasible ways of reducing ruminant CH(4) production while improving productivity; it is therefore critical to conduct a full system analysis to select the best combination of approaches or new technologies to be applied under long-term field conditions.