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1.
Osteoporos Int ; 32(2): 233-241, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32820370

RESUMEN

The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk. INTRODUCTION: It is unclear whether subsequent fractures or a certain location and sequence of subsequent fractures are associated with mortality risk in the elderly. We aimed to investigate the relationship between subsequent fractures and mortality risk. METHODS: Using the Korean National Health Insurance Research Database, we analyzed the cohort data of 24,756 patients aged > 60 years who sustained fractures between 2002 and 2013. Cox regression was used to assess the mortality risk associated with the number, locations, and sequences of subsequent fractures. RESULTS: Mortality hazard ratios (HRs) for women and men were shown to be associated with the number of subsequent fractures (one, 1.63 (95% confidence interval [CI], 1.48-1.80) and 1.42 (95% CI, 1.28-1.58); two, 1.75 (95% CI, 1.47-2.08) and 2.03 (95% CI, 1.69-2.43); three or more, 2.46(95% CI, 1.92-3.15) and 1.92 (95% CI, 1.34-2.74), respectively). For women, the mortality risk was high when hip (HR, 2.49; 95% CI, 1.80-3.44) or vertebral (HR, 1.40; 95% CI, 1.03-1.90) fracture occurred as a second fracture. Compared with a single hip fracture, there was a high mortality risk in the group with hip fracture after the first vertebral fracture (HR, 2.90; 95% CI, 1.86-4.54), followed by vertebral fracture after the first hip fracture (HR, 1.90; 95% CI, 1.12-3.22). CONCLUSION: The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk.


Asunto(s)
Fracturas de Cadera , Fracturas de la Columna Vertebral , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Modelos de Riesgos Proporcionales , Factores de Riesgo , Columna Vertebral
2.
Folia Morphol (Warsz) ; 74(3): 372-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26339820

RESUMEN

The Visible Korean research team used Mimics software (Materialise, Leuven, Belgium) for the segmentation and subsequent surface reconstruction of heart structures using information obtained from sectioned images of a cadaver. Twenty-six heart components were outlined in advance on Photoshop (Adobe Systems, San Jose, CA, USA). By use of the Mimics, the outlined images were then browsed along with the vertical planes as well as the 3-dimensional surface models, which were immediately built by piling the images. Erroneous delineation was readily detected and revised until satisfactory heart models were acquired. The surface models and the selected sectioned images in horizontal, coronal, and sagittal planes were inputted into a PDF file, where any combinations of reconstructed constituents could be displayed and rotated by the user. Mimics software accelerated the segmentation and surface reconstruction of heart anatomical structures. Similar benefits hopefully result from various serial images of other organs. The PDF file, and plane and stereoscopic image data are being distributed to others, and should prove valuable for medical students and clinicians.

3.
Cell Death Dis ; 5: e1292, 2014 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-24922076

RESUMEN

Cisplatin (cis-diaminedichloroplatinum-II) is an extensively used chemotherapeutic agent, and one of its most adverse effects is ototoxicity. A number of studies have demonstrated that these effects are related to oxidative stress and DNA damage. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as a key regulator of cellular energy metabolism and homeostasis. Here, we demonstrate for the first time that, in cisplatin-mediated ototoxicity, the levels and activities of SIRT1 are suppressed by the reduction of intracellular NAD(+) levels. We provide evidence that the decrease in SIRT1 activity and expression facilitated by increasing poly(ADP-ribose) transferase (PARP)-1 activation and microRNA-34a through p53 activation aggravates cisplatin-mediated ototoxicity. Moreover, we show that the induction of cellular NAD(+) levels using ß-lapachone (ß-Lap), whose intracellular target is NQO1, prevents the toxic effects of cisplatin through the regulation of PARP-1 and SIRT1 activity. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological agents could be a promising therapeutic approach for protection from cisplatin-induced ototoxicity.


Asunto(s)
Antineoplásicos/efectos adversos , Cisplatino/efectos adversos , Pérdida Auditiva/inducido químicamente , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , NAD/metabolismo , Animales , Antineoplásicos/farmacología , Cisplatino/farmacología , Pérdida Auditiva/genética , Pérdida Auditiva/metabolismo , Pérdida Auditiva/patología , Masculino , Ratones , Ratones Noqueados , MicroARNs/genética , MicroARNs/metabolismo , NAD/genética , NAD(P)H Deshidrogenasa (Quinona)/genética , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Sirtuina 1/genética , Sirtuina 1/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
4.
Horm Metab Res ; 45(10): 722-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23681752

RESUMEN

Protein aggregation is a major obstacle in maintaining the stability of therapeutic proteins. In previous studies, fusion between a stabilizing peptide (SP) and human growth hormone (hGH) resulted in improved solubility and stability compared with hGH alone, although the bioactivity of the protein was not confirmed in vivo. In this study, we evaluated the bioefficacy of hGH and SP-hGH in vivo using a mouse model. Subcutaneous injections of 30 µg of hGH or SP-hGH were administered to 8-month-old female mice, twice a week for 14 weeks. Neither hGH nor SP-hGH significantly affected body weight or blood glucose levels compared with control mice. Interestingly, abdominal fat was significantly reduced in SP-hGH-treated mice compared with hGH-treated mice. While total cholesterol, HDL, and LDL levels were slightly higher in both groups, TG levels were significantly reduced in both SP-hGH and hGH-treated mice compared with control mice. IGF-1 levels in the liver were increased in both the SP-hGH and hGH groups, thereby inducing liver cell proliferation. These results suggest that SP fusion with hGH attained similar or improved bioefficacy compared with hGH alone.


Asunto(s)
Hormona de Crecimiento Humana/química , Hormona de Crecimiento Humana/farmacología , Animales , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Femenino , Hormona de Crecimiento Humana/administración & dosificación , Humanos , Células MCF-7 , Ratones , Ratones Endogámicos ICR , Estabilidad Proteica , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Resultado del Tratamiento
5.
Microsc Microanal ; 19(1): 111-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23380005

RESUMEN

Stereological analysis has been coupled with transmission electron microscope (TEM) orientation mapping to investigate the grain boundary character distribution in nanocrystalline copper thin films. The use of the nanosized (<5 nm) beam in the TEM for collecting spot diffraction patterns renders an order of magnitude improvement in spatial resolution compared to the analysis of electron backscatter diffraction patterns in the scanning electron microscope. Electron beam precession is used to reduce dynamical effects and increase the reliability of orientation solutions. The misorientation distribution function shows a strong misorientation texture with a peak at 60°/[111], corresponding to the Σ3 misorientation. The grain boundary plane distribution shows {111} as the most frequently occurring plane, indicating a significant population of coherent twin boundaries. This study demonstrates the use of nanoscale orientation mapping in the TEM to quantify the five-parameter grain boundary distribution in nanocrystalline materials.

6.
Poult Sci ; 91(9): 2370-5, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22912475

RESUMEN

Prevalence and antimicrobial resistance profiles of Salmonella serotypes isolated from 7 chicken meat brands produced by different integrated broiler operations in Korea were determined. In total, 210 samples were collected from retail supermarkets in Seoul, South Korea, and analyzed for the presence of Salmonella. Of 210 chicken meat samples, overall Salmonella prevalence was 22.4%. Salmonella Enteritidis was the dominant serovar, with an isolation rate of 57.4% from the Salmonella-positive chickens, followed by Salmonella Montevideo. Salmonella isolates frequently were resistant to various antibiotics, including 100% to erythromycin, 87% to cephalothin, 85% to nalidixic acid, and 70% to streptomycin. Of the 47 isolates, 41 (87.2%) isolates were resistant to 3 or more antibiotics. Moreover, the Salmonella profiles of each chicken meat brand were different by broiler operation. Brand A showed the highest prevalence of Salmonella (18 isolates, 60%), whereas brand G showed the lowest prevalence (one isolate, 3.3%). Eight among the 18 isolates of brand A were resistant to 11 antibiotics, whereas 5 of the 6 brand C isolates were resistant to only 2 antibiotics. This study demonstrates that a high proportion of chicken meat in Korea is contaminated with Salmonella and the prevalence and antimicrobial resistance patterns of Salmonella of chicken meat differ significantly according to the integrated broiler operation.


Asunto(s)
Crianza de Animales Domésticos/métodos , Antibacterianos/farmacología , Carne/microbiología , Salmonella/clasificación , Salmonella/efectos de los fármacos , Animales , Pollos/microbiología , Farmacorresistencia Bacteriana , Prevalencia , República de Corea , Serotipificación
7.
Horm Metab Res ; 44(6): 422-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22499548

RESUMEN

Leptin is a protein hormone produced by adipocytes. It is secreted into the blood stream and plays a key role in regulating body energy homeostasis by inhibiting feeding behavior followed by decreased body weight. Because protein aggregation is a major problem in therapeutic proteins, we previously demonstrated that a stabilizing peptide (SP) fusion protein of leptin (SP-leptin) appeared to resist aggregation induced by agitation, freezing/thawing, or heat stress. In this study, we fused mouse leptin with the stabilizing peptide and compared the biological activities of leptin and SP-leptin in vivo using a male C57Bl mouse model and ex vivo using MCF7 breast cancer cell lines. Each group of mice was treated with saline, leptin, and SP-leptin for 20 days and the differences in body weight, food intake, abdominal fat contents, and TG concentration were measured. The SP-leptin appeared to decrease the body weight and food intake in male C57Bl mice more significantly than wild type leptin, and the SP-leptin treated MCF7 cells displayed better cell proliferation than leptin. As a consequence of decreased body weight, the SP-leptin treated mouse group showed decreased abdominal fat contents and low triglyceride (TG) concentration. Moreover, the SP-leptin treated mouse group had fewer lipid droplets in liver and reduced lipid droplet size when analyzed by Oil red O and H & E staining. These results demonstrated that SP-leptin is more effective than wild type leptin in normal mice in lowering their body weight and fat contents in the abdominal region, the serum, and the liver.


Asunto(s)
Leptina/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Péptidos/farmacología , Proteínas Recombinantes de Fusión/farmacología , Grasa Abdominal/efectos de los fármacos , Adiposidad/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Línea Celular Tumoral , Conducta Alimentaria/efectos de los fármacos , Humanos , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Estabilidad Proteica/efectos de los fármacos
8.
Bone Marrow Transplant ; 47(3): 374-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21478916

RESUMEN

The role of hypomethylating agent therapy (HMT) as a bridge to allogeneic hematopoietic cell transplantation (alloHCT) in patients with myelodysplastic syndrome (MDS) remains undetermined. We investigated the feasibility of HMT followed by alloHCT in patients with MDS. In all, 19 patients who received HMT followed by alloHCT were analyzed. A total of 7 patients were classified as low-risk and 12 as high-risk, based on World Health Organization (WHO) classification at the time of HMT. HMT consisted of decitabine in 9 patients and azacitidine in 10. After HMT, two patients achieved CR, six mCR, three hematologic improvement alone, and six SD in terms of best response. HMT did not alter WHO classification in 15 patients (79%), whereas 1 patient (5%) improved and 3 (16%) progressed to AML. Most patients (95%) received a non-myeloablative conditioning regimen based on fludarabine/BU/anti-thymocyte globulin, and peripheral blood-mobilized stem cells. Neutrophil and platelet engraftments were achieved in 95 and 79% of patients, respectively. The incidences of acute and chronic GVHD were 42 and 26%, respectively. In all, 2-year OS rates were 68%, and the overall outcomes of those who achieved CR/mCR with HMT tended to be superior to those without CR/mCR. HMT followed by alloHCT was a feasible and effective treatment strategy for patients with MDS.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Síndromes Mielodisplásicos/terapia , Trasplante Homólogo/métodos , Adulto , Anciano , Azacitidina/administración & dosificación , Azacitidina/análogos & derivados , Metilación de ADN , Decitabina , Supervivencia sin Enfermedad , Estudios de Factibilidad , Femenino , Enfermedad Injerto contra Huésped/terapia , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/inmunología , Neutrófilos/citología , Riesgo , Acondicionamiento Pretrasplante/métodos , Resultado del Tratamiento
9.
AJNR Am J Neuroradiol ; 31(8): 1536-40, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20395391

RESUMEN

BACKGROUND AND PURPOSE: IV administration of tPA is accepted as a standard treatment for acute cerebral ischemia, but the clinical outcomes cannot be guaranteed in patients who are not recanalized after IV-tPA and in those who are not eligible for IV-tPA. In this study, outcomes from groups of patients treated with additional IA thrombolytic therapy with the use or omission of IV-tPA administration were compared. MATERIALS AND METHODS: IA thrombolytic therapy (thrombolytic agents combined with mechanical intervention) was attempted in those patients who were not eligible for IV-tPA and who showed continuous major vessel occlusion after IV-tPA. Sixty-three patients were divided into 2 groups: a tPA group (n = 29, IA thrombolysis after IV-tPA) and a non-tPA group (n = 34, IA thrombolysis without IV-tPA). These groups were subdivided according to match or mismatch DWI/PWI after MR imaging. Treatment results were compared by recanalization rate, clinical outcome, mortality, and ICH rate. RESULTS: The recanalization rate was 79.3% in the tPA group and 55.9% in the non-tPA group (χ(2) test, P < .05). Subgroup analysis between DWI/PWI mismatch in the tPA group and DWI/PWI mismatch in the non-tPA group also showed no statistical difference in recanalization rate, favorable clinical outcome, and mortality (χ(2) test, P > .05), but the significant ICH rate was high in the tPA group (χ(2) test, P < .05). CONCLUSIONS: Additional IA thrombolytic treatment after full-dose IV-tPA administration might be an acceptable treatment option for patients with DWI/PWI mismatch.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/administración & dosificación , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/administración & dosificación , Enfermedad Aguda , Adolescente , Adulto , Anciano , Isquemia Encefálica/patología , Humanos , Inyecciones Intraarteriales , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Persona de Mediana Edad , Retratamiento , Estudios Retrospectivos , Adulto Joven
10.
J Intellect Disabil Res ; 53(4): 339-52, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19309420

RESUMEN

BACKGROUND: This study was conducted to examine the impact of a 1-year intervention for children with intellectual disabilities (ID) in Vietnam. METHOD: Subjects were 30 preschool-aged children with ID (ages 3 to 6 years). Sixteen were assigned to an intervention group and 14 to a control group. Based on the Portage Curriculum (CESA 5 2003), the intervention trained parents to work with their children through modelling and coaching by teachers during weekly home visits. RESULTS: Comparison of pre-, mid- and post-intervention assessments of the children based on the Vineland Adaptive Behavior Scales (Sparrow et al. 1984a) indicated that the intervention was promising: children in the intervention group improved significantly in most domains of adaptive behaviours, and also performed significantly better than the control group in the areas of personal care and motor skills. CONCLUSIONS: The results from the Vietnam programme are discussed in terms of its implications and strategies for developing programmes for children with disabilities in developing countries.


Asunto(s)
Servicios de Atención de Salud a Domicilio/organización & administración , Discapacidad Intelectual/epidemiología , Adaptación Psicológica , Niño , Preescolar , Femenino , Humanos , Masculino , Trastornos de la Destreza Motora/epidemiología , Encuestas y Cuestionarios , Vietnam/epidemiología
11.
Tree Physiol ; 29(6): 847-56, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19324693

RESUMEN

Although bamboo is one of the most important woody crops in Asia, information on its genome is still very limited. To investigate the relationship among Poaceae members and to understand the mechanism of albino mutant generation in vitro, the complete chloroplast genome of two economically important bamboo species, Dendrocalamus latiflorus Munro and Bambusa oldhamii Munro, was determined employing a strategy that involved polymerase chain reaction (PCR) amplification using 443 novel primers designed to amplify the chloroplast genome of these two species. The lengths of the B. oldhamii and D. latiflorus chloroplast genomes are 139,350 and 139,365 bp, respectively. The organization structure and the gene order of these two bamboos are identical to other members of Poaceae. Highly conserved chloroplast genomes of Poaceae facilitated sequencing by the PCR method. Phylogenetic analysis using both chloroplast genomes confirmed the results obtained from studies on chromosome number and reproductive organ morphology. There are 23 gaps, insertions/deletions > 100 bp, in the chloroplast genomes of 10 genera of Poaceae compared in this study. The phylogenetic distribution of these gaps corresponds to their taxonomic placement. The sequences of these two chloroplast genomes provide useful information for studying bamboo evolution, ecology and biotechnology.


Asunto(s)
Bambusa/genética , Genoma del Cloroplasto/genética , Poaceae/genética , Bambusa/clasificación , Filogenia , Poaceae/clasificación , Reacción en Cadena de la Polimerasa
12.
Eur J Neurol ; 15(11): 1212-5, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18754763

RESUMEN

BACKGROUND AND PURPOSE: The medical treatment available for patients with essential tremor (ET) is often inadequate. Furthermore, the efficacy of the medical treatments currently available for patients with ET of cranial nerve areas is less satisfactory than that of the medical treatments available for patients with ET involving the upper extremities. This pilot study was performed to evaluate whether zonisamide (ZNS) is effective in the treatment of patients with isolated head tremor. METHODS: All subjects with isolated head tremor were randomly treated with either ZNS or propranolol. After a washout period, the subjects were switched to the alternative drug. RESULTS: ZNS was found to be more effective in the treatment of patients with isolated head tremor than propranolol. No severe adverse effects were reported with either ZNS or propranolol. CONCLUSION: ZNS may be more useful than propranolol for the treatment of ET patients with head tremor.


Asunto(s)
Temblor Esencial/tratamiento farmacológico , Isoxazoles/administración & dosificación , Músculos del Cuello/efectos de los fármacos , Antagonistas Adrenérgicos beta/administración & dosificación , Anciano , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Trastornos de la Conciencia/inducido químicamente , Relación Dosis-Respuesta a Droga , Temblor Esencial/fisiopatología , Femenino , Movimientos de la Cabeza/efectos de los fármacos , Movimientos de la Cabeza/fisiología , Humanos , Isoxazoles/efectos adversos , Músculos del Cuello/fisiopatología , Cooperación del Paciente , Propranolol/administración & dosificación , Resultado del Tratamiento , Zonisamida
13.
Acta Neurochir Suppl ; 101: 157-60, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18642652

RESUMEN

INTRODUCTION: Most previous reports indicate that traditional bilateral kyphoplasty improves patient function and restores height of collapsed vertebral bodies, but limited data about the effects of unilateral kyphoplasty on clinical and radiological outcome are available. MATERIAL AND METHODS: One hundred five patients were treated by unilateral kyphoplasty between January 2004 and December 2006. These patients underwent 105 operations to treat 132 vertebral compression fractures between T8 and L5. Sagittal alignment was analyzed from standing radiographs. Clinical outcomes were determined by comparison of preoperative and postoperative data from patient-reported index (visual analogue pain scale score). Radiographs were assessed as to percent vertebral collapse, vertebral height restoration and local kyphosis correction. RESULTS: Mean length of follow-up was 15.3 months (range 3-36 months); improved height 2.3 and 4.0 mm in the anterior and medial columns, respectively (P > 0.05); Cobb angle increased 3.0 degrees (P < 0.05), visual analogue pain scale score improved from 8.7 +/- 1.4 before surgery to 2.3 +/- 0.9 (P < 0.05); no adverse medical or procedural complications; 6.8% (9/132) cement leakage rate. CONCLUSION: Unilateral transpedicular kyphoplasty improves physical function, reduces pain, and may correct kyphotic deformity associated with vertebral compression fractures. This result shows comparable to traditional bilateral kyphoplasty procedure.


Asunto(s)
Cateterismo/métodos , Descompresión Quirúrgica/métodos , Fracturas por Compresión/cirugía , Osteoporosis/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Fracturas por Compresión/complicaciones , Fracturas por Compresión/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagen , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento
14.
Xenobiotica ; 37(4): 356-65, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17455110

RESUMEN

1. The high-level expression of mammalian cytochrome P450 in bacteria usually requires modification of the amino-terminal region of the enzyme. The effect of altering amino acids in the N-terminus of human recombinant CYP1A2 on its catalytic activity was investigated herein. 2. Rates of 7-ethoxyresorufin O-deethylation by CYP1A2a (a form made by altering the amino acids LLL of CYP1A2 to RER at positions 3-5) in reconstituted systems were significantly low compared with those of other CYP1A2 N-terminal variants at a low ratio of cytochrome P450 to NADPH-cytochrome P450 reductase, but not at higher reductase concentrations. 3. CYP1A2a-dependent ethoxyresorufin O-deethylase activity in a cumene hydroperoxide-supported system was approximately 2-fold higher than other CYP1A2 N-terminal variants. 4. Our results suggest that modification of three N-terminal amino acids in CYP1A2 alters the interaction between CYP1A2 and the reductase in reconstituted phospholipid vesicles and in the bicistronic membranes.


Asunto(s)
Secuencia de Aminoácidos , Citocromo P-450 CYP1A2/biosíntesis , Membranas Artificiales , Proteínas Recombinantes/biosíntesis , Catálisis , Citocromo P-450 CYP1A2/química , Citocromo P-450 CYP1A2/genética , Escherichia coli/genética , Expresión Génica , Humanos , Mutagénesis , Oxazinas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
15.
J Periodontal Res ; 41(4): 288-96, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16827722

RESUMEN

BACKGROUND AND OBJECTIVE: Lipopolysaccharide is thought to be a major virulence factor of pathogens associated with periodontal diseases and is believed to stimulate bone resorption in vivo. Although Prevotella nigrescens has been implicated in periodontitis, its role in osteoclastogenesis has not been reported. In this study, we investigated the effects of lipopolysaccharide from P. nigrescens on the formation of osteoclasts and the production of cytokines related to osteoclast differentiation. MATERIAL AND METHODS: Mouse bone marrow mononuclear cells were cultured in the presence of macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappaB ligand (RANKL), with or without lipopolysaccharide. Bone marrow mononuclear cells were also cocultured with calvarial osteoblastic cells in the presence or absence of lipopolysaccharide. Osteoclast formation was determined by tartrate-resistant acid phosphatase cytochemistry. The production of osteoprotegerin (OPG), M-CSF, tumor necrosis factor alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and prostaglandin E2 (PGE2) was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: P. nigrescens lipopolysaccharide inhibited osteoclast differentiation from bone marrow mononuclear cells cultured in the presence of M-CSF and RANKL. However, in the coculture system, P. nigrescens lipopolysaccharide stimulated osteoclastogenesis. Notably, P. nigrescens lipopolysaccharide decreased OPG production but increased TGF-beta secretion. In addition, treatment with P. nigrescens lipopolysaccharide increased PGE2 production during the late stage of the culture period. There was no difference in M-CSF and TNF-alpha production. CONCLUSION: These results demonstrate that P. nigrescens lipopolysaccharide stimulates osteoclastogenesis in the coculture system by decreasing the production of OPG and increasing the production of TGF-beta and PGE2. Through the mechanisms involving these factors, P. nigrescens lipopolysaccharide may cause alveolar bone resorption in periodontal diseases.


Asunto(s)
Pérdida de Hueso Alveolar/microbiología , Lipopolisacáridos/farmacología , Osteoclastos/efectos de los fármacos , Prevotella nigrescens/patogenicidad , Animales , Células de la Médula Ósea/efectos de los fármacos , Proteínas Portadoras/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Dinoprostona/biosíntesis , Femenino , Glicoproteínas/biosíntesis , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos ICR , Osteoblastos/efectos de los fármacos , Osteoclastos/citología , Osteoprotegerina , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , Receptores Citoplasmáticos y Nucleares/biosíntesis , Receptores del Factor de Necrosis Tumoral/biosíntesis , Factor de Crecimiento Transformador beta/biosíntesis
16.
Clin Exp Dermatol ; 28(4): 420-4, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12823306

RESUMEN

To determine the best molecular method for diagnosing leprosy, two sets of Mycobacterium leprae-specific primers were compared. Fresh biopsies and slit skin smear samples were obtained from 67 leprosy patients and examined by touchdown (TD) PCR using primers amplifying either a 129-bp fragment of the RLEP repetitive sequence or a 360-bp fragment of the 18-kDa protein gene of M. leprae. Seventeen of 30 (56.7%) biopsy specimens and four of 37 (10.8%) slit skin smear specimens were positive using the primer for the 18-kDa protein gene, whereas 24 of 30 (80%) biopsy and 27 of 37 (73%) slit skin smear samples showed detectable PCR products in the RLEP repetitive sequence. Twenty-one of 31 cases (67.7%) with a bacterial index of zero were PCR positive for the primer RLEP repetitive sequence. These results demonstrate that detection of M. leprae using PCR with primers to a RLEP sequence is more sensitive and specific than PCR with the 18-kDa protein gene primers and also slit smears with acid fast staining. PCR of RLEP repetitive sequences is therefore a useful means of detecting M. leprae DNA even when it is present at very low levels.


Asunto(s)
Proteínas Bacterianas/genética , Lepra/diagnóstico , Mycobacterium leprae/genética , Reacción en Cadena de la Polimerasa/métodos , Anticuerpos Antibacterianos/sangre , Cartilla de ADN , Humanos , Lepra/microbiología , Mycobacterium leprae/aislamiento & purificación , Secuencias Repetitivas de Ácidos Nucleicos , Piel/microbiología
17.
J Clin Pharm Ther ; 27(6): 419-25, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12472981

RESUMEN

OBJECTIVE: To determine population-based pharmacokinetic parameters for intravenous valproic acid, and the factors influencing these parameters, in Korean adults. METHODS: Valproic acid concentrations were obtained using a peak and trough sampling scheme for 102 Korean epileptic patients who were not taking concurrent antiepileptic medication. Three hundred and fifty-four serum concentrations were analysed according to a one-compartment model with a mixed effect modelling method (NONMEM Ver 5.0). The influence of body-weight (kg), height, daily valproic acid dose (mg/day), body mass index (kg/m2), sex, and age on volume of distribution (Vd) and clearance (CL) was assessed in the course of analysis. RESULTS: Vd and CL of valproic acid increased with body-weight. No significant influence of the other screened covariates was observed. The final regression model was: [equation: see text]. Interindividual variabilities (coefficient of variation) for CL and Vd were 32 and 18%, respectively. Residual error including intraindividual variability was 26.7%. CONCLUSION: The current results may be used as a basic reference to optimize drug therapy with intravenous valproic acid. Further research on the paediatric population is necessary to confirm the non-linearity of the relation between body-weight and Vd.


Asunto(s)
Anticonvulsivantes/farmacocinética , Ácido Valproico/farmacocinética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/sangre , Pueblo Asiatico , Teorema de Bayes , Índice de Masa Corporal , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Infusiones Intravenosas , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Modelos Biológicos , Ácido Valproico/administración & dosificación , Ácido Valproico/sangre , Ácido Valproico/uso terapéutico
18.
Artículo en Inglés | MEDLINE | ID: mdl-11088539

RESUMEN

We study by Monte Carlo simulations the fractal nature of the backbone network for the irreversible kinetic gelation model in both two and three dimensions. The fractal dimension of the backbone network generated at the gel point is measured by various methods, and results are found to be consistent with that of the standard percolation backbone. Our observation is different from the previous work in three dimensions, where a distinctly larger value was observed. We also measure the spectral dimension d(B)(s) and the fractal dimension d(B)(w) of random walks on a backbone, defined by, respectively, the probability of random walks returning to the starting point and the rms displacements after t time steps. Results are also found to be consistent with the corresponding percolation values. We therefore conclude that the backbone network of the kinetic gelation model exhibits the same static and dynamic properties as those of the standard percolation backbone.

19.
J Org Chem ; 65(2): 536-42, 2000 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-10813969

RESUMEN

The binding affinity and selectivity of a new ionophore, [1(8)]starand (1), toward alkali metal cations in methanol were examined through NMR titration experiments and free energy perturbation (FEP) and molecular dynamics simulations. The preference was determined to be K(+) > Rb(+) > Cs(+) > Na(+) >> Li(+) in both FEP simulations and NMR experiments. The FEP simulation results were able to predict the relative binding free energies with errors less than 0.13 kcal/mol, except for the case between Li(+) and Na(+). The cation selectivity was rationalized by analyzing the radial distribution functions of the M-O and M-C distances of free metal cations in methanol and those of metal-ionophore complexes in methanol.

20.
Plant Cell Rep ; 19(3): 257-262, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30754904

RESUMEN

Bioelastic protein-based polymers (PBP) have several medical (prevention of post-surgical adhesions) and non-medical (biodegradable plastic) applications. This study compares expression levels of PBP genes (synthetic) integrated into the nuclear genome or the large single-copy (LSC) or inverted repeat (IR) region of the chloroplast genome in transgenic tobacco plants. Polymer transcripts accumulated up to 100-fold higher in the IR plants than in those of nuclear transgenic plants. Integration of foreign genes into all of the chloroplast genomes (homoplasmy) and higher levels of polymer transcripts were observed only in the IR and not in LSC transgenic plants. Expression of the polymer protein was further confirmed by Western blot analysis.

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