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1.
Geophys Res Lett ; 49(3): e2021GL096069, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35859568

RESUMEN

Water storage plays an important role in mitigating heat and flooding in urban areas. Assessment of the water storage capacity of cities remains challenging due to the inherent heterogeneity of the urban surface. Traditionally, effective storage has been estimated from runoff. Here, we present a novel approach to estimate effective water storage capacity from recession rates of observed evaporation during precipitation-free periods. We test this approach for cities at neighborhood scale with eddy-covariance based latent heat flux observations from 14 contrasting sites with different local climate zones, vegetation cover and characteristics, and climates. Based on analysis of 583 drydowns, we find storage capacities to vary between 1.3 and 28.4 mm, corresponding to e-folding timescales of 1.8-20.1 days. This makes the urban storage capacity at least five times smaller than all the observed values for natural ecosystems, reflecting an evaporation regime characterized by extreme water limitation.

2.
Artículo en Chino | MEDLINE | ID: mdl-32746565

RESUMEN

Objective: To investigate the effect of perfluorooctane sulfonate (PFOS) on inflammatory factors in human placental trophoblast (HTR-8/Svneo) cells. Methods: HTR-8/Svneo cells were exposed to different concentrations of PFOS (0, 0.01, 0.1, 1.0 mg/L) for 24 h, and the cell survival rates were measured by CCK8. Secretion levels of interleukin-6 (IL-6) , tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) were detected by ELISA. The mRNA expressions of IL-6, TNF-α and IL-10 were detected by fluorescence quantitative PCR. One-way ANOVA was used to analyse the expressions of inflammatory factors. Results: Compared with the control group, the survival rates of 0.1 and 1.0 mg/L PFOS groups were significantly decreased (P<0.05) . Compared with the control group, the secretion levels of IL-6 were decreased in the 0.01, 0.1 and 1.0 mg/L PFOS groups (P<0.05) , the concentrations of TNF-α were increased in the 0.01 and 1.0 mg/L PFOS groups (P<0.05) , and the concentrations of IL-10 were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) . Compared with the control group, the expressions of IL-6 mRNA were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) , and the expressions of IL-10 mRNA were decreased in the 0.01 mg/L, 0.1 mg/L and 1.0 mg/L PFOS groups (P<0.05) . Conclusion: PFOS can induce changes in the secretion levels of inflammatory cytokines in HTR-8/Svneo cells, resulting in decreased activity of placental trophoblast cells and abnomal placental function.


Asunto(s)
Ácidos Alcanesulfónicos/toxicidad , Fluorocarburos/toxicidad , Placenta/efectos de los fármacos , Trofoblastos/efectos de los fármacos , Femenino , Humanos , Embarazo , Pruebas de Toxicidad , Factor de Necrosis Tumoral alfa/genética
3.
Sci Rep ; 7(1): 6146, 2017 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-28733577

RESUMEN

For recent years, devices that generate non-thermal plasma (NTP) have been introduced into the field of dermatology. Since NTP has demonstrated strong anti-pathogenic activity with safety of use, NTP was first applied to sterilize the skin surface to aid in the healing of various kinds of skin diseases. However, the effect of NTP on skin regeneration has not yet been fully explored. In this study, the effect of NTP on the growth of keratinocytes was tested using the HaCaT human keratinocyte cell line and HRM2 hairless mice. Treatment with NTP allowed confluent keratinocytes to escape from G1 cell cycle arrest and increased the proportion of cells in S and G2 phases. In particular, NTP treatment immediately dispersed E-cadherin-mediated cell-to-cell interactions, resulting in the translocation of ß-catenin to the nucleus and leading to the enhanced transcription of target genes including c-MYC and cyclin D1. Moreover, repeated treatment of the mice with NTP also stimulated epidermal expansion by activating ß-catenin in the epidermal cells. The symptoms of cellular DNA damage were not detected after NTP treatment. Taken together, these results demonstrate that NTP may be employed as a new type of skin regenerating device.


Asunto(s)
Queratinocitos/metabolismo , Gases em Plasma/administración & dosificación , Regeneración/efectos de los fármacos , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , beta Catenina/metabolismo , Animales , Antígenos CD/metabolismo , Cadherinas/metabolismo , Ciclo Celular , Línea Celular , Núcleo Celular/metabolismo , Modelos Animales de Enfermedad , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Masculino , Ratones , Gases em Plasma/farmacología , Cicatrización de Heridas/efectos de los fármacos
4.
Mikrobiol Z ; 78(5): 2-11, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30141858

RESUMEN

The red yeasts are currently widely discussed and controversial group of yeasts because of the growing number of reports of their ability to become opportunistic pathogens of plants, animals and humans. The aim of this work was complex identifcation of the red yeast culture isolated from gastrointestinal tract of healthy Hucul long-liver from the Carpathians highland region of Ukraine. Torularhodin was found to be a major component within yeast culture carotenoids complex. According to conventional biochemical and morphological approaches as well as to molecular biological investigation of internal transcribed spacer region (ITS) of ribosomal operon it was concluded that isolate belonged to species Rhodotorula mucilaginosa.


Asunto(s)
Tracto Gastrointestinal/microbiología , Rhodotorula/clasificación , Rhodotorula/aislamiento & purificación , Carotenoides/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Humanos , Ucrania
5.
Intern Med J ; 45(4): 428-35, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25533739

RESUMEN

BACKGROUND: Albuminuria is associated with increased risk of multiple adverse health outcomes, such as progressive renal failure, cardiovascular disease and death. However, in the general population, it is uncertain whether albuminuria is associated with elevated heart rate, which is an independent and powerful risk factor for cardiovascular disease. AIM: To investigate whether an elevated heart rate is an independent factor associated with albuminuria in the general adult population of Korea. METHODS: A cross-sectional analysis was carried out on 5198 Korean adults aged 19 years or older who participated in the fifth (2011) Korea National Health and Nutrition Examination Survey (KNHANES V-2). RESULTS: The prevalence of albuminuria showed an increasing trend throughout the whole range of heart rate, even after adjusting for confounders (P = 0.002). The increment was most profound at the heart rate of 70-75 and >76 beats per minute (b.p.m.; P = 0.011). In multiple logistic regression analysis, age (P < 0.001), hypertension (P < 0.001), diabetes (P < 0.001), hypertriglyceridaemia (P = 0.025), estimated glomerular filtration rate (P = 0.028) and heart rate (P = 0.023) were independently associated with the presence of albuminuria in Korean adults. Compared with participants with heart rate ≤ 64 b.p.m., the odds ratio (95% CI) for albuminuria was 1.50 (1.15-1.96) for those with heart rate ≥ 76 b.p.m. CONCLUSIONS: The prevalence of albuminuria is independently associated with heart rate in the general adult population of Korea.


Asunto(s)
Albuminuria/diagnóstico , Albuminuria/epidemiología , Frecuencia Cardíaca , Encuestas Nutricionales , Vigilancia de la Población , Adulto , Anciano , Estudios Transversales , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales/tendencias , República de Corea/epidemiología , Adulto Joven
6.
J Eur Acad Dermatol Venereol ; 27(5): 609-16, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22404745

RESUMEN

BACKGROUND: Vitiligo is an acquired pigmentary disorder caused by the destruction of melanocytes. Two of the major theories regarding the pathogenesis of vitiligo are the autoimmune theory and autocytotoxicity theory, but, the precise pathogenetic mechanism is still not clarified. OBJECTIVES: We investigated the effects of ET-1, tacrolimus and tumour necrosis factor-α (TNF-α) on proliferation and migration of cultured normal human melanocytes (NHMs). We also sought to clarify the theoretical rationale underlying the topical tacrolimus monotherapy or tacrolimus-UV combination therapy as tools for vitiligo treatment. METHODS: The effects of ET-1, tacrolimus and TNF-α on proliferation/migration of cultured NHMs were investigated by MTT assay/Boyden chamber transwell migration assay. We also examined roles of CXC-chemokine receptor II (CXCR II) and matrix metalloproteinases (MMPs) in such conditions. RESULTS: ET-1 exerted a stimulatory effect on melanocyte proliferation and migration, but, tacrolimus exerted a stimulatory effect only on melanocyte migration higher than ET-1. TNF-α inhibited melanocyte proliferation in a dose-dependent manner. Paradoxically, TNF-α-pretreated NHMs exhibited an enhanced proliferative efficiency after being switched to ET-1. We found CXCRII was highly expressed in TNF-α-incubated melanocytes than the agents-free control, and ET-1 treatment after TNF-α preincubation showed the higher levels of CXCRII expression than the condition incubated with TNF-α alone. Moreover, the greater activities of MMP-2 and MMP-9 induced by tacrolimus than ET-1, reflected tacrolimus would enhance migration stimulatory effect in cultured NHMs. CONCLUSIONS: Topical tacrolimus can be used an effective agent for vitiligo treatment as monotherapy, maybe due to its migration stimulatory action or TNF-α inhibitory property, and also as a component in combination therapy with UV treatment, considering the more upregulated MMPs activities are induced and the more effective migrations are feasible by itself than ET-1.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Endotelina-1/fisiología , Inmunosupresores/farmacología , Melanocitos/efectos de los fármacos , Fototerapia , Tacrolimus/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Vitíligo/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Receptores CXCR/metabolismo , Tacrolimus/administración & dosificación , Tacrolimus/uso terapéutico
7.
Horm Metab Res ; 43(13): 956-61, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22072433

RESUMEN

Administration of recombinant human growth hormone (rhGH) in obesity has been known to lead to a decrease in visceral adiposity and an increase in lean body mass. Most studies have used supraphysiological doses of rhGH, which were administered daily or every other day. We aimed to evaluate whether weekly administered low dose of sustained-release rhGH (SR-rhGH) could play a therapeutic role in the treatment of abdominal obesity. Prospective, single-arm, open-label, multicenter pilot study was carried out. Participants were 26 adults aged 40-65 years old with abdominal obesity (male: waist circumference >90 cm, female: waist circumference >85 cm). The subjects were given 3 mg of SR-rhGH, administered subcutaneously, weekly for 26 weeks. SR-rhGH treatment for 26 weeks increased the IGF-1 level by 56.53±76.09 µg/l (SDS 0.77±1.12) compared to the baseline (p=0.0022). After 26 weeks, SR-rhGH treatment reduced abdominal visceral adipose tissue (VAT) (140.35±75.97 to 128.43±73.85 cm2, p=0.0038). Average waist circumference decreased from 96.25±6.41 to 91.93±6.13 cm (p<0.0001) after treatment. However, body weight or lean body mass did not show any significant change. In conclusion, SR-rhGH treatment for 26 weeks reduced abdominal visceral fat and waist circumference without severe adverse events. Further studies may be considered on the role of weekly administered SR-rhGH as a treatment for abdominal obesity.


Asunto(s)
Preparaciones de Acción Retardada/administración & dosificación , Hormona de Crecimiento Humana/administración & dosificación , Grasa Intraabdominal/metabolismo , Obesidad Abdominal/tratamiento farmacológico , Circunferencia de la Cintura/efectos de los fármacos , Adulto , Anciano , Preparaciones de Acción Retardada/efectos adversos , Esquema de Medicación , Femenino , Hormona de Crecimiento Humana/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Obesidad Abdominal/metabolismo , Obesidad Abdominal/fisiopatología , Estudios Prospectivos
8.
Horm Metab Res ; 43(1): 48-54, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20865648

RESUMEN

Patients with hypopituitarism have the feature of metabolic syndrome, including central obesity, insulin resistance, and dyslipidemia. Because metabolic syndrome, including insulin resistance, is the main pathogenesis of the development of nonalcoholic fatty liver disease (NAFLD), we considered that patients diagnosed with hypopituitarism have an increased risk of developing NAFLD. We compared control subjects and hypopituitary men in metabolic parameters and the frequency of fatty liver on abdominal ultrasonography, and analyzed associating factors with the severity of the fatty liver in patients with hypopituitarism. 34 male patients with hypopituitarism and 40 age and sex-matched control subjects were included. The frequency of fatty liver on abdominal ultrasonography was significantly higher in hypopituitary men compared to control subjects (32.5% vs. 70.6%, p=0.001). Ln CRP and free fatty acids were significantly elevated in hypopituitary patients with fatty liver compared to patients without fatty liver. Ln GH was significantly lower in hypopituitary patients with fatty liver. The severity of fatty liver on abdominal ultrasonography correlated with negatively Ln GH, after adjusting for the BMI effect (p=0.020). There is a difference only between the severe fatty liver group and normal liver group in the analysis of the mean Ln GH level between 4 groups according to the severity of fatty liver (p=0.036). In conclusion, NAFLD is more common in hypopituitary patients than control subject. Severe growth hormone deficiency in hypopituitarism was associated with the severe degree of hepatic steatosis in NAFLD.


Asunto(s)
Hipopituitarismo/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Estudios Transversales , Hígado Graso/diagnóstico por imagen , Hígado Graso/etiología , Hígado Graso/metabolismo , Hormona del Crecimiento/metabolismo , Humanos , Hipopituitarismo/complicaciones , Hipopituitarismo/diagnóstico por imagen , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Ultrasonografía
9.
Rev Sci Instrum ; 81(3): 035109, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20370215

RESUMEN

A detection method using a self-sensing cantilever is more desirable than other detection methods (optical fiber and laser beam bounce detection) that are bulky and require alignment. The advantage of the self-sensing cantilever is its simplicity, particularly its simple structure. It can be used for the construction of an atomic force microscopy system with a vacuum, fluids, and a low temperature chamber. Additionally, the self-actuating cantilever can be used for a high speed scanning system because the bandwidth is larger than the bulk scanner. Frequently, ZnO film has been used as an actuator in a self-actuating cantilever. In this paper, we studied the characteristics of the self-sensing and self-actuating cantilever with an integrated Wheatstone bridge circuit substituting the ZnO film with a lead zirconate titanate (PZT) film as the actuator. We can reduce the leakage current (to less than 10(-4) A/cm(2)) in the PZT cantilever and improve sensor sensitivity through a reduction of noise level from the external sensor circuit using the Wheatstone bridge circuit embedded into the cantilever. The self-sensing and actuating cantilever with an integrated Wheatstone bridge circuit was compared with a commercial self-sensing cantilever or self-sensing and actuating cantilever without an integrated Wheatstone bridge circuit. The measurement results have shown that sensing the signal to noise level and the minimum detectable deflection improved to 4.78 mV and 1.18 nm, respectively. We believe that this cantilever allows for easier system integration and miniaturization, provides better controllability and higher scan speeds, and offers the potential for full automation.

10.
J Appl Microbiol ; 109(2): 415-430, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20092541

RESUMEN

AIMS: This work has examined the effects of a polycyclic aromatic hydrocarbon and selected toxic metals on fungal populations in a soil microcosm. METHODS AND RESULTS: By using fungal ribosomal intergenic spacer analysis (F-RISA) in combination with real-time PCR quantification, four fungi (D63P2-1, D63C2-1, D21Cu1-1 and D63Pb2-2) with specific primer pairs to each were successfully evaluated for their potential as bioindicators in response to pyrene, copper (Cu) and lead (Pb), supplied singly and in combination. CONCLUSIONS: F-RISA coupled with real-time PCR is a useful approach for the identification of microorganisms with potential as bioindicators of organic and toxic metal contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: These bioindicators could be monitored for their population changes that may indicate pollutant-induced perturbations in a given system.


Asunto(s)
Monitoreo del Ambiente/métodos , Hongos/efectos de los fármacos , Metales/farmacología , Pirenos/farmacología , Microbiología del Suelo , Contaminantes del Suelo/farmacología , Cobre/farmacología , ADN Espaciador Ribosómico/química , Hongos/clasificación , Hongos/genética , Plomo/farmacología , Metales/análisis , Reacción en Cadena de la Polimerasa , Pirenos/análisis , Análisis de Secuencia de ADN , Contaminantes del Suelo/análisis
11.
Osteoporos Int ; 21(5): 847-53, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19633881

RESUMEN

UNLABELLED: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side effect of bisphosphonate therapy. The incidence of BRONJ is known to be low among patients treated with oral bisphosphonates. We investigated the prevalence, demographics, clinical manifestations, and treatment outcome of 24 patients with oral BRONJ in Asian populations. INTRODUCTION: The long-term safety of oral bisphosphonates is clinically important considering the rare but potentially serious complications such as bisphosphonate-related osteonecrosis of the jaw (BRONJ) versus the effect of reducing and preventing osteoporotic fracture. The incidence of BRONJ is known to be low among patients treated with oral bisphosphonates around the world. However, the prevalence in those taking oral bisphosphonates for osteoporosis in Asian populations is unknown. Moreover, a recent article, showing that the majority of reported patients who received alendronate were Asian American, raised concern about the prevalence of oral BRONJ in Asian populations. The objective of this study was to investigate the estimated prevalence, clinical characteristics, and treatment outcome of oral BRONJ in Asian populations. METHODS: From October 2005 to December 2008, a retrospective review of medical charts identified 24 patients receiving oral bisphosphonates diagnosed as BRONJ at the Department of Oral and Maxillofacial Surgery, Yonsei University Dental Hospital, Seoul, South Korea. RESULTS: The estimated prevalence of oral BRONJ was 0.05-0.07%. The average oral bisphosphonate treatment duration was 43.1 months (range, 5-120 months). Treatment with oral antibiotics and/or surgery including sequestrectomy or alveolectomy showed relatively favorable results. CONCLUSIONS: The prevalence of oral BRONJ in Korea is similar to that reported previously in Western populations. We suggest that recognition of BRONJ and appropriate management pre- and post-dental surgery might reduce the frequency of BRONJ among patients receiving oral bisphosphonates.


Asunto(s)
Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Enfermedades Maxilomandibulares/inducido químicamente , Osteonecrosis/inducido químicamente , Administración Oral , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Esquema de Medicación , Femenino , Humanos , Enfermedades Maxilomandibulares/diagnóstico por imagen , Enfermedades Maxilomandibulares/terapia , Masculino , Persona de Mediana Edad , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/terapia , Osteoporosis/tratamiento farmacológico , Radiografía Panorámica , Estudios Retrospectivos , Resultado del Tratamiento
12.
J Appl Microbiol ; 108(3): 985-997, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19761462

RESUMEN

AIMS: For identification of members of the fungal order Eurotiales, an 18S rRNA gene-based oligonucleotide microarray was developed and optimized. METHODS AND RESULTS: Eurotiales-specific probes covering most members of the Eurotiales as well as species-specific probes were designed and evaluated with three pure cultures (two fungi from the Eurotiales and one fungus from the Hypocreales). Nearly complete 18S rRNA genes of each reference culture were amplified and fluorescently labelled by random priming. CONCLUSIONS: Positive and negative hybridization results confirmed that the Eurotiales probes tested in this study could correctly identify members of the Eurotiales. The species-specific probes were also capable of species-level detection. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings demonstrate the potential applications of a phylogenetic oligonucleotide microarray approach to characterizing fungal species and populations in environmental and other samples.


Asunto(s)
Eurotiales/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN Ribosómico 18S/genética , Eurotiales/clasificación , ARN de Hongos/genética , Especificidad de la Especie
13.
J Appl Microbiol ; 108(6): 2030-40, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19922595

RESUMEN

AIMS: This study aimed to isolate and identify potential polycyclic aromatic hydrocarbon (PAH)-degrading and/or metal-tolerant fungi from PAH-contaminated and metal-contaminated soils. METHODS AND RESULTS: Pyrene-degrading fungi were isolated from contaminated soil and tested for metal (Cu, Zn and Pb) compound solubilization and metal accumulation. Three strains of Fusarium solani and one of Hypocrea lixii were able to degrade more than 60% of initial supplied pyrene (100 mg l(-1)) after 2 weeks. The isolates were grown on toxic metal (Cu, Pb and Zn)-containing media: all isolates accumulated Cu in their mycelia to values ranging from c. 5.9 to 10.4 mmol per kg dry weight biomass. The isolates were also able to accumulate Zn (c. 3.7-7.2 mmol per kg dry weight biomass) from zinc phosphate-amended media. None of the isolates accumulated Pb. CONCLUSIONS: These fungal isolates appear to show promise for use in bioremediation of pyrene or related xenobiotics and removal of copper and zinc from wastes contaminated singly or in combination with these substances. SIGNIFICANCE AND IMPACT OF THE STUDY: Microbial responses to mixed organic and inorganic pollution are seldom considered: this research highlights the abilities of certain fungal strains to interact with both xenobiotics and toxic metals and is relevant to other studies on natural attenuation and bioremediation of polluted sites.


Asunto(s)
Cobre/metabolismo , Fusarium/metabolismo , Hypocrea/metabolismo , Pirenos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Zinc/metabolismo , Biodegradación Ambiental , Fusarium/aislamiento & purificación , Gasolina , Hypocrea/aislamiento & purificación , Hidrocarburos Policíclicos Aromáticos/metabolismo , Suelo/análisis
14.
J Phys Condens Matter ; 22(9): 095901, 2010 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-21389426

RESUMEN

Strontium stannate is under study as an ultra-stable dielectric material for microelectronic applications at low temperatures. It is known to have a remarkably temperature-independent dielectric constant from 27 K to room temperature. However, we report anomalies in the Raman spectra, dielectric response, and differential thermal analysis of strontium stannate compatible with a structural phase transition at 160 K. Further anomalies are seen in calorimetric and Raman data (but not dielectric data) that suggest another phase transition at 270 K. A preliminary x-ray powder diffraction study confirms a small change in the pseudo-cubic lattice constant a(T) at the lower transition.

15.
J Pharm Biomed Anal ; 37(2): 405-10, 2005 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-15708686

RESUMEN

This report describes an automated coupled column microbore-high-performance liquid chromatography (HPLC) with fluorescence detection for direct determination of verapamil in small volume of rat plasma. We used HPLC system consisting of three columns such as precolumn, intermediate and analytical column and six-port switching valve and injected small volume of rat plasma to the system without sample preparation. An aliquot of sample was directly injected into Capcell Pak MF Ph precolumn for clean-up and enrichment, 35 mm Capcell Pak C18, intermediate column for concentration of compounds and 250 mm Capcell Pak C18 analytical column for separation of compounds and two mobile phases are used as mobile phase A (50mM ammonium phosphate, pH 4.5) and B (50mM ammonium phosphate:acetonitrile=70:30 v/v). Analysis of verapamil and internal standard, propranolol was performed with direct injection of 10 microl of rat plasma to the system and were eluted at 22 and 12 min, respectively, at a mobile phase flow rate of 0.5 (mobile phase A) and 0.15 ml/min (mobile phase B). The peaks of verapamil and internal standard were good shapes and well separated from any interfering endogenous peaks during a total run time of 25 min. The calibration curve for verapamil showed good linearity (r(2)=0.9997) over the concentration range of 0.01-2.50 microg/ml. The mean RSD (%) values of intra-day (n=5) and inter-day (n=5) variability of verapamil ranged from 1.96 to 9.06 and 0.62 to 3.08%, respectively. The LOD and LOQ were 0.01 and 0.025 microg/ml, respectively, for verapamil using 10 microl of rat plasma. An automated coupled column microbore-HPLC method was successfully applied to a pharmacokinetic study after intravenous injection of 3mg/kg of verapamil to the normal and dimethylnitrosamine (DMN)-induced hepatofibrotic rats.


Asunto(s)
Verapamilo/sangre , Animales , Disponibilidad Biológica , Calibración , Cromatografía Líquida de Alta Presión/métodos , Modelos Animales de Enfermedad , Inyecciones Intravenosas , Cirrosis Hepática/sangre , Masculino , Ratas , Ratas Sprague-Dawley
16.
Invest Ophthalmol Vis Sci ; 42(12): 2795-803, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11687520

RESUMEN

PURPOSE: To determine the effect of interleukin (IL)-1alpha and tumor necrosis factor (TNF)-alpha on cytokine, chemokine, and receptor expression in corneal stromal cells; the effect of corneal scrape injury on monocyte chemotactic and activating factor (MCAF) expression and monocyte-macrophage influx into the stroma; and the effect of MCAF and granulocyte colony-stimulating factor (G-CSF) microinjection on inflammatory cell infiltration into the stroma. METHODS: Gene array technology was used to evaluate changes in cytokine, chemokine, and receptor gene expression in stromal fibroblasts in response to IL-1alpha and TNFalpha. Expression of MCAF mRNA and protein was monitored with an RNase protection assay and Western blot analysis, respectively. Keratocyte MCAF protein expression in the rabbit cornea was detected with immunocytochemistry. After epithelial scrape injury, monocytes-macrophages were detected in rabbit corneas, by immunocytochemistry for monocyte-macrophage antigen. Inflammatory cell infiltration after MCAF and G-CSF microinjection into the stroma of mouse corneas was monitored with hematoxylin and eosin staining. RESULTS: IL-1alpha or TNFalpha upregulated the expression of several proinflammatory chemokines in stromal fibroblasts in culture. These included G-CSF, MCAF, neutrophil-activating peptide (ENA-78), and monocyte-derived neutrophil chemotactic factor (MDNCF). MCAF mRNA upregulation was confirmed by RNase protection assay, and MCAF protein was detected by Western blot analysis. MCAF protein was detected in keratocytes at 4 hours and 24 hours after epithelial injury, but not in keratocytes in the unwounded cornea. Corneal epithelial injury triggered the influx of monocytes-macrophages into the corneal stroma in the rabbit. Microinjection of MCAF and G-CSF into mouse cornea resulted in the influx of monocytes-macrophages and granulocytes, respectively, into the stroma. CONCLUSIONS: Proinflammatory chemokine induction in keratocytes is mediated by IL-1alpha and TNFalpha. The proinflammatory chemokines produced by the keratocytes probably trigger the influx of inflammatory cells into the stroma after epithelial injury associated with corneal surgery, contact lenses, or trauma.


Asunto(s)
Movimiento Celular/fisiología , Quimiocinas/biosíntesis , Sustancia Propia/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Interleucina-1/farmacología , Macrófagos/fisiología , Monocitos/fisiología , Factor de Necrosis Tumoral alfa/farmacología , Western Blotting , Quimiocina CCL2/farmacología , Quimiocinas/genética , Sustancia Propia/metabolismo , Fibroblastos/metabolismo , Perfilación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos/farmacología , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/biosíntesis , Receptores CCR2 , Receptores de Quimiocina/biosíntesis , Regulación hacia Arriba
17.
Biotechnol Prog ; 17(5): 958-62, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11587590

RESUMEN

A polymer (PDMS: poly(dimethylsiloxane)) microchip for capillary gel electrophoresis that can separate different sizes of DNA molecules in a small experimental scale is presented. This microchip can be easily produced by a simple PDMS molding method against a microfabricated master without the use of elaborate bonding processes. This PDMS microchip could be used as a single use device unlike conventional microchips made of glass, quartz or silicon. The capillary channel on the chip was partially filled with agarose gel that can enhance separation resolution of different sizes of DNA molecules and can shorten the channel length required for the separation of the sample compared to capillary electrophoresis in free-flow or polymer solution format. We discuss the optimal conditions for the gel preparation that could be used in the microchannel. DNA molecules were successfully driven by an electric field and separated to form bands in the range of 100 bp to 1 kbp in a 2.0% agarose-filled microchannel with 8 mm of effective separation length.


Asunto(s)
Materiales Biocompatibles Revestidos/química , ADN/aislamiento & purificación , Dimetilpolisiloxanos/química , Siliconas/química , Electroforesis Capilar/instrumentación , Electroforesis Capilar/normas , Microquímica , Microscopía Fluorescente , Microscopía por Video , Miniaturización , Peso Molecular , Reproducibilidad de los Resultados , Sefarosa
18.
Arch Ophthalmol ; 119(6): 889-96, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11405841

RESUMEN

Biological diversity in the wound healing response is thought to be a major factor limiting the predictability of the outcome of refractive surgical procedures such as laser in situ keratomileusis and photorefractive keratectomy. Corneal wound healing is critical to the success of topography-linked or wave front-linked excimer laser ablation to optimize visual performance. This is because of the importance of retaining subtle features of custom ablation and the tendency of epithelial hyperplasia and stromal remodeling to obscure these features following either procedure. The corneal wound healing response is exceedingly complex. Keratocyte apoptosis, which occurs in response to epithelial injury, is the earliest observable event in the wound healing cascades and is therefore an excellent target for pharmacological intervention. Alterations of surgical technique can be designed to limit keratocyte apoptosis and the subsequent events in corneal wound healing. Abnormalities of the cascades could contribute to the pathogenesis of corneal diseases. For example, recent data have suggested that perturbation of the keratocyte apoptosis/mitosis balance could underlie the development of keratoconus in a proportion of patients.


Asunto(s)
Córnea/fisiología , Queratomileusis por Láser In Situ , Queratectomía Fotorrefractiva , Cicatrización de Heridas/fisiología , Animales , Apoptosis/fisiología , Córnea/citología , Células Epiteliales/fisiología , Fibroblastos/fisiología , Humanos , Láseres de Excímeros , Mitosis/fisiología , Errores de Refracción/metabolismo , Procedimientos Quirúrgicos Refractivos
19.
Electrophoresis ; 22(2): 328-33, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11288901

RESUMEN

We report on the development of a hybrid polydimethylsiloxane (PDMS)-glass microchip for genetic analysis by functional integration of polymerase chain reaction (PCR) and capillary gel electrophoresis (CGE), and on related temperature control systems for PCR on a PDMS-glass hybrid microchip. The microchip was produced by molding PDMS against a microfabricated master with comparatively simple and inexpensive methods. PCR was successfully carried out on the PDMS-glass hybrid microchip with 500 bp target of lambdaDNA and the amplified gene was subsequently analyzed by CGE on the same PDMS-glass microchip. The chip could be considered as an inexpensive single-use apparatus compared to glass or silicon-made microchips for the same purpose.


Asunto(s)
Electroforesis Capilar/instrumentación , Microquímica/instrumentación , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa/instrumentación , Bacteriófago lambda/química , ADN Viral/análisis , Dimetilpolisiloxanos , Electroforesis Capilar/métodos , Diseño de Equipo , Técnicas Genéticas/instrumentación , Vidrio , Procesamiento de Imagen Asistido por Computador , Miniaturización , Reacción en Cadena de la Polimerasa/métodos , Siliconas , Temperatura
20.
Curr Eye Res ; 23(1): 69-76, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11821989

RESUMEN

PURPOSE: To identify and differentiate cell cycle and differentiation genes that are up-regulated or down-regulated in human corneal epithelial cells in response to alternative epithelium-modulating cytokines epidermal growth factor (EGF), hepatocyte growth factor (HGF) or keratinocyte growth factor (KGF). METHODS: Primary cultures human corneal epithelial cell (HCE) were treated with 25 ng/ml of EGF, 25 ng/ml HGF, 25 ng/ml KGF, or vehicle for 8 hours. Complementary DNA (cDNA) probes were synthesized from total cellular RNA isolated from the HCE cells. The cDNA probes were hybridized to the Atlas human cell cycle/differentiation array membrane. RNAse protection assay was used to confirm up-regulation of the serine/threonine-protein kinase PITALRE gene by EGF, KGF, and HGF. RESULTS: The expression of one hundred and eleven cell cycle and differentiation genes was monitored with the gene array system. It was found that these epithelial cell-modulating cytokines shared similar effects on some of the cell cycle and differentiation genes that were monitored, but had specific effects on some cytokines. Up-regulation of PITALRE gene expression was confirmed using RNAse protection assay. CONCLUSION: EGF, HGF and KGF had differential effects on cell cycle- and differentiation-related gene expression in corneal epithelial cells. For example, all three mitogenic growth factors up-regulated the expression of cyclin D1 (BCL-1 oncogene) and serine/threonine-protein kinase PITALRE in the primary cultured human corneal epithelial cells. However, EGF and KGF, but not HGF, up-regulated expression of the E2F-1 pRB-binding protein gene. Thus, while these three epithelial mitogens have similar effects on many genes that were analyzed, important differences were noted that may relate to differing effects of these growth factors on corneal epithelial cells. Studies to analyze the significance of the identified differences among these growth factors are in progress.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/fisiología , Proteínas de Unión al ADN , Factor de Crecimiento Epidérmico/farmacología , Epitelio Corneal/efectos de los fármacos , Factores de Crecimiento de Fibroblastos/farmacología , Factor de Crecimiento de Hepatocito/farmacología , Proteínas de Ciclo Celular/genética , Diferenciación Celular , Células Cultivadas , Ciclina D1/metabolismo , Quinasa 9 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/metabolismo , Sondas de ADN , Factores de Transcripción E2F , Factor de Transcripción E2F1 , Epitelio Corneal/metabolismo , Factor 7 de Crecimiento de Fibroblastos , Perfilación de la Expresión Génica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Factores de Transcripción/metabolismo , Regulación hacia Arriba
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