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1.
Scand J Rheumatol ; 48(3): 198-206, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30475093

RESUMEN

OBJECTIVE: The aim was to investigate prevalence and degree of ocular and oral involvement in patients with primary Sjögren's syndrome (PSS). METHOD: We analysed 134 participants from the Korean Initiative of PSS cohort who completed a 2 year follow-up oral and ocular sign test. The severity of keratoconjunctivitis sicca (KCS) was determined with the Schirmer I test value (STV) [abnormal (AB) ≤ 5 mm/5 min; normal (N) > 5 mm/5 min]. Salivary gland dysfunction (SGD) was determined by unstimulated whole salivary (UWS) flow rate [moderate to severe (MS) < 0.1 mL/min; mild (Mi) ≥ 0.1 mL/min]. Subgroups were divided into three groups according to STV and severity of SGD: AB-STV/MS-SGD, AB-STV/Mi-SGD, and N-STV/MS-SGD groups. We analysed the changes in STV and SGD during the follow-up period. RESULTS: Among the 134 participants enrolled in this study, 105 (78%) were placed in the AB-STV/MS-SGD group, 16 (12%) in the AB-STV/Mi-SGD, and 13 (10%) in the N-STV/MS-SGD at the 2 year follow-up. The AB-STV/Mi-SGD group was younger than the other two groups, and had a lower Xerostomia Inventory score and lower level of ß2-microglobulin. Participants in the N-STV/MS-SGD group had less hyperimmunoglobulinaemia, rheumatoid factor (RF), and antinuclear antibodies (ANAs). Patients and those with positive RF or ANA ≥ 1:320 at baseline were more likely to have abnormal STV at the 2 year follow-up. CONCLUSIONS: Patients with PSS and positive RF or ANA ≥ 1:320 at baseline may benefit from regular ophthalmology examinations, even if they do not have KCS at baseline or dry eye symptoms.


Asunto(s)
Queratoconjuntivitis Seca , Síndrome de Sjögren/complicaciones , Xerostomía , Adulto , Factores de Edad , Anticuerpos Antinucleares/sangre , Estudios de Cohortes , Femenino , Humanos , Queratoconjuntivitis Seca/diagnóstico , Queratoconjuntivitis Seca/etiología , Queratoconjuntivitis Seca/inmunología , Masculino , Persona de Mediana Edad , Prevalencia , República de Corea/epidemiología , Factor Reumatoide/sangre , Índice de Severidad de la Enfermedad , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/epidemiología , Evaluación de Síntomas , Xerostomía/diagnóstico , Xerostomía/etiología , Xerostomía/inmunología
2.
Anaesthesia ; 74(1): 51-56, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30383296

RESUMEN

Several studies have investigated the effects of general anaesthesia on neurodevelopment in children, with conflicting results. The potential for early general anaesthesia exposure to impact neurodevelopment in children may cause significant concern for parents. Administering a questionnaire in 200 parents, we aimed to explore their knowledge, concerns and perceptions, and determine factors which influence parents' willingness for their children to participate in relevant research studies. A significant proportion of parents (40%) were concerned that general anaesthesia may affect their child's neurodevelopment. Generally these concerns arose from the parents' own beliefs or preconceived ideas and only 25.5% had encountered prior information in this domain. Parents with children aged 2 years or younger, those whose children had previous general anaesthesia exposure, and those who had encountered information about potential neurodevelopmental effects were most likely to be concerned. The majority of parents (68%) would agree to participate in research studies, especially if they were able to receive the test results. Anaesthetists should pre-emptively initiate discussions to address any potential misconceptions regarding the effects of general anaesthesia on neurodevelopment in children.


Asunto(s)
Anestesia General/efectos adversos , Anestésicos Generales/efectos adversos , Discapacidades del Desarrollo/inducido químicamente , Sistema Nervioso/crecimiento & desarrollo , Padres , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Lactante , Masculino , Singapur , Factores Socioeconómicos , Encuestas y Cuestionarios
3.
J Dairy Sci ; 102(4): 2844-2853, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30799108

RESUMEN

Synbiotics, a combination of prebiotics and probiotics, produce synergistic effects to promote gastrointestinal health. Herein, we investigated the synbiotic interaction between the Lactobacillus rhamnosus strain GG (LGG; a probiotic strain) and tagatose (a prebiotic) in a dextran sulfate sodium (DSS)-induced colitis murine model. Initially, body weight, food intake, and clinical features were dramatically decreased after treatment with DSS, and the addition of LGG, tagatose, or both ameliorated these effects. In our pyrosequencing analysis of fecal microbiota, DSS treatment increased the abundance of Proteobacteria and decreased that of Firmicutes. When LGG and tagatose were administered as synbiotics, the gut microbiota composition recovered from the dysbiosis caused by DSS treatment. In particular, the abundance of Bacteroides, Lactobacillus, and Akkermansia was significantly associated with probiotic, prebiotic, and synbiotic treatments. Taken together, our results suggest that LGG and tagatose as synbiotics can alleviate colitis, and synbiotics could be applied as dietary supplements in dairy foods such as yogurt and cheese.


Asunto(s)
Colitis/inducido químicamente , Colitis/terapia , Hexosas/uso terapéutico , Lacticaseibacillus rhamnosus , Simbióticos , Animales , Sulfato de Dextran/toxicidad , Heces/microbiología , Hexosas/administración & dosificación , Quelantes del Hierro/administración & dosificación , Quelantes del Hierro/farmacología , Lactobacillus , Lacticaseibacillus rhamnosus/clasificación , Ratones , Microbiota
4.
Osteoporos Int ; 28(11): 3251-3259, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28748389

RESUMEN

The risk factors for atypical femur fracture in patients exposed to bisphosphonates for at least 1 year were examined. Prolonged and continuous use of bisphosphonates, long-term use of glucocorticoids, and a higher body mass index were associated with increased risk of atypical femur fracture. INTRODUCTION: The purpose of the present study is to determine whether rheumatoid arthritis (RA) and other clinical factors are associated with an increased risk of bisphosphonate (BP)-related atypical femur fracture (AFF). METHODS: A retrospective nested case-control study of patients who had taken BPs for at least 1 year was conducted. Patients with AFF were identified by reviewing surgical and radiographic records. Three controls with no history of AFFs were randomly selected and age- and sex-matched to each patient with AFFs. Cox proportional hazard models were used to analyze the independent contribution of risk factors to BP-related AFF. RESULTS: Among the 35,104 patients prescribed BPs for at least 1 year, 43 females (mean age, 68 years) suffered AFFs (0.12%). Patients with AFFs were exposed to BPs for a mean of 7.3 years. Patients with AFFs were exposed to BPs for longer than those without AFFs and continued treatment without a drug holiday. More patients with AFF than controls had taken glucocorticoids and disease-modifying anti-rheumatic drugs. Multivariate Cox regression analyses estimated that long-term use of glucocorticoids, prolonged exposure to BP without cessation, and every 1 kg/m2 increase in the body mass index (BMI) increased the hazard ratio for AFFs by 3.0, 5.2, and 1.2, respectively. CONCLUSIONS: Prolonged and continuous use of BPs, long-term use of glucocorticoids, and a higher BMI increase the risk of AFFs. Switching long-term BP and glucocorticoid users to other bone-protective agents should be considered.


Asunto(s)
Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Fracturas del Fémur/inducido químicamente , Absorciometría de Fotón/métodos , Anciano , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Esquema de Medicación , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/fisiopatología , Glucocorticoides/efectos adversos , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/tratamiento farmacológico , Radiografía , Estudios Retrospectivos , Factores de Riesgo
5.
Scand J Rheumatol ; 46(1): 49-55, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27098775

RESUMEN

OBJECTIVES: Fatigue is a common clinical manifestation in patients with primary Sjögren's syndrome (pSS). The aims of this study were to investigate the association between fatigue severity and other clinical characteristics in pSS patients and to determine the factors contributing to fatigue. METHOD: We analysed 257 participants from the Korean Initiative of pSS (KISS), a prospective pSS cohort. Fatigue was assessed according to the fatigue domain of the European League Against Rheumatism (EULAR) Sjögren's Syndrome Patient-Reported Index (ESSPRI). Health-related quality of life (HRQoL) was evaluated using the EuroQol-5 dimensions (EQ-5D) questionnaire. Multiple linear regression analysis was used to estimate the effect of each variable on fatigue severity. RESULTS: The median total ESSPRI score was 5 [interquartile range (IQR) 4-6]. Thirty-four per cent of patients reported a fatigue score > 5. Younger and premenopausal patients presented with more fatigue (p = 0.013 and p < 0.001, respectively). Higher Xerostomia Inventory (XI) scale (p < 0.001) and Ocular Surface Dryness Index (OSDI) (p < 0.001) scores were observed in patients with a fatigue score > 5. Pain, xerostomia, and age were determined to be significantly associated with fatigue severity after adjusting for depression/anxiety, OSDI score, and the presence of fibromyalgia using a multivariate general linear model. The ESSPRI fatigue score was correlated with the EQ-5D by time trade-off (TTO) values and visual analogue scale (VAS) scores. CONCLUSIONS: In Korean patients with pSS, younger age, xerostomia, and pain were correlated significantly with fatigue, and fatigue was associated with HRQoL.


Asunto(s)
Fatiga/etiología , Síndrome de Sjögren/complicaciones , Factores de Edad , Estudios de Cohortes , Fatiga/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Calidad de Vida , República de Corea/epidemiología , Síndrome de Sjögren/epidemiología , Xerostomía/etiología
6.
Lupus ; 24(2): 210-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25305214

RESUMEN

We investigated the clinical and laboratory characteristics of pregnancies with systemic lupus erythematosus (SLE) and identified lupus flare predictors during pregnancy. Additionally, we examined lupus activity and pregnancy outcomes in SLE patients who continued, discontinued or underwent no hydroxychloroquine (HCQ) treatment during pregnancy. We retrospectively analyzed 179 pregnancies in 128 SLE patients at Seoul St. Mary's Hospital, Korea, between 1998 and 2012 and then assessed the clinical profiles and maternal and fetal outcomes. Overall, 90.5% of pregnancies resulted in a successful delivery and were divided into two groups: those who experienced lupus flares (80 pregnancies, 44.7%) and those who did not (99 pregnancies, 55.3%). Increased preeclampsia, preterm births, low birth weight, intrauterine growth restriction (IUGR), and low 1-minute Apgar scores occurred in pregnancies with lupus flares compared to pregnancies in quiescent disease. Lupus flares were predicted by HCQ discontinuation, a history of lupus nephritis, high pre-pregnancy serum uric acid and low C4 levels. Our study indicates that achieving pre-pregnancy remission and continuing HCQ treatment during pregnancy are important for preventing lupus flares.


Asunto(s)
Hidroxicloroquina/uso terapéutico , Lupus Eritematoso Sistémico/fisiopatología , Complicaciones del Embarazo/fisiopatología , Resultado del Embarazo , Adulto , Antirreumáticos/administración & dosificación , Antirreumáticos/uso terapéutico , Puntaje de Apgar , Femenino , Retardo del Crecimiento Fetal/epidemiología , Estudios de Seguimiento , Humanos , Hidroxicloroquina/administración & dosificación , Recién Nacido , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Nefritis Lúpica/epidemiología , Preeclampsia/epidemiología , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Nacimiento Prematuro/epidemiología , República de Corea , Estudios Retrospectivos , Ácido Úrico/sangre
7.
Lupus ; 24(12): 1300-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26038343

RESUMEN

This study was performed to investigate the clinical characteristics of lupus cystitis and determine the risk factors and clinical outcomes of lupus cystitis in patients with systemic lupus erythematosus (SLE). We retrospectively reviewed 1064 patients at Seoul St. Mary's Hospital in Seoul, Korea, from 1998 to 2013. Twenty-four patients had lupus cystitis. Lupus cystitis was defined as unexplained ureteritis and/or cystitis as detected by imaging studies, cystoscopy, or bladder histopathology without urinary microorganisms or stones. Three-fourths of patients with lupus cystitis had concurrent lupus mesenteric vasculitis (LMV). The initial symptoms were gastrointestinal in nature for most patients (79.2%). High-dose methylprednisolone was initially administered to most patients (91.7%) with lupus cystitis. Two patients (8.3%) died of urinary tract infections. Sixty-five age- and sex-matched patients with SLE who were admitted with other manifestations were included as the control group. Patients with lupus cystitis showed a lower C3 level (p = 0.031), higher SLE Disease Activity Index score (p = 0.006), and higher ESR (p = 0.05) upon admission; more frequently had a history of LMV prior to admission (p < 0.001); and less frequently had a history of neuropsychiatric lupus (p = 0.031) than did patients with SLE but without lupus cystitis. The occurrence of lupus cystitis was associated with a history of LMV (OR, 21.794; 95% CI, 4.061-116.963). The median follow-up period was 3.4 years, and the cumulative one-year mortality rate was 20%. Complications developed in 33.3% of patients with lupus cystitis and were related to survival (log-rank p = 0.021). Our results suggest that the possibility of lupus cystitis should be considered when a patient with SLE and history of LMV presents with gastrointestinal symptoms or lower urinary tract symptoms. Development of complications in patients with lupus cystitis can be fatal. Thus, intensive treatment and follow-up are needed, especially in the presence of complications.


Asunto(s)
Cistitis/etiología , Lupus Eritematoso Sistémico/complicaciones , Vasculitis/complicaciones , Adulto , Cistitis/tratamiento farmacológico , Femenino , Enfermedades Gastrointestinales/complicaciones , Humanos , Estimación de Kaplan-Meier , Lupus Eritematoso Sistémico/tratamiento farmacológico , Metilprednisolona/uso terapéutico , República de Corea , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X , Adulto Joven
8.
Lupus ; 24(7): 764-72, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25712250

RESUMEN

We investigated obstetric outcomes and comorbidities during pregnancy in females with preexisting lupus nephritis (LN) and identified predictors for renal flare. In cases of renal flare during pregnancy, we assessed the long-term post-delivery renal outcome. We performed a retrospective analysis of 183 systemic lupus erythematosus (SLE) pregnancies including blood chemistry, urinalysis, urinary protein, and disease activity recorded at prepregnancy, during pregnancy, and at one month, six months, and one year post-delivery. Pregnancies with preexisting LN had a greater frequency of adverse obstetric outcomes and maternal comorbidity. Renal flares occurred in 50.7% of pregnancies with preexisting LN, 89.2% of which were reactivations. Renal flare among pregnancies with SLE was predicted based on preexisting lupus nephritis (OR 17.73; 95% CI, 5.770-54.484), an active disease prior to pregnancy (OR 2.743; 95% CI, 1.074-7.004), and prepregnancy eGFR < 90 ml/min/1.73 m(2) (OR 11.151; 95% CI, 3.292-37.768). Persistent LN one year after delivery was observed in 33.3% of pregnancies. The median follow-up time after delivery was 5.9 (3.1-9.7) years and chronic kidney disease (CKD) occurred in 21.4% of pregnancies with renal flare. In patients with renal flare, failing to achieve a ≥ 50% reduction in urine protein levels within six months, longer total duration of renal flare, and acute kidney injury at renal flare was associated with CKD development. Females with preexisting LN should achieve remission before pregnancy. When patients experience renal flares during pregnancy, it is important to reduce the proteinuria level by >50% within six months and to achieve early remission for excellent long-term renal outcomes.


Asunto(s)
Nefritis Lúpica/fisiopatología , Complicaciones del Embarazo/fisiopatología , Embarazo/sangre , Embarazo/orina , Adulto , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Nefritis Lúpica/sangre , Nefritis Lúpica/tratamiento farmacológico , Nefritis Lúpica/orina , Embarazo/estadística & datos numéricos , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/tratamiento farmacológico , Complicaciones del Embarazo/orina , Resultado del Embarazo , República de Corea , Estudios Retrospectivos
9.
J Appl Microbiol ; 118(3): 718-26, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25494714

RESUMEN

AIMS: This study aimed to investigate the potential of Bacillus methylotrophicus as a probiotic. METHODS AND RESULTS: A Bacillus isolate designated strain C14 was isolated from Korean traditional fermented soybean paste (doenjang). The strain was identified, and its physiological and biochemical properties were characterized. The gastrointestinal tolerance and immunomodulatory function of strain C14 were also investigated. Strain C14 was identified as B. methylotrophicus by analysis of its biochemical properties using the API 50CHB system and by phylogenetic analysis of the 16S rDNA sequence. Strain C14 showed >80% and >75% of survival for artificial gastric juices (pH 2.5 and 1% pepsin) and 0.5% (w/v) bile salt, respectively. Heat-killed B. methylotrophicus C14 inhibited the adhesion of various pathogens and enhanced the adhesion of probiotic bacteria to Caco-2 cells. The heat-killed cells also induced high levels of immune cell proliferation compared with the control and stimulated interleukin-6 and tumour necrosis factor-α production in mouse macrophages. CONCLUSIONS: Bacillus methylotrophicus C14 could be used as a probiotic. SIGNIFICANCE AND IMPACT OF THE STUDY: Recently identified B. methylotrophicus is a new potential probiotic with high gastrointestinal tolerance.


Asunto(s)
Bacillus/fisiología , Probióticos , Alimentos de Soja/microbiología , Animales , Bacillus/clasificación , Bacillus/aislamiento & purificación , Ácidos y Sales Biliares , Células CACO-2 , Femenino , Fermentación , Tracto Gastrointestinal/microbiología , Humanos , Interleucina-6/biosíntesis , Macrófagos/inmunología , Ratones , Datos de Secuencia Molecular , Ganglios Linfáticos Agregados/inmunología , Probióticos/aislamiento & purificación , Factor de Necrosis Tumoral alfa/biosíntesis
10.
Diabet Med ; 25(4): 469-75, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18346161

RESUMEN

AIMS: To investigate associations between gamma-glutamyltransferase (GGT) and components of metabolic syndrome (MS), insulin resistance and inflammatory markers in the Korean population. METHODS: The 3508 subjects enrolled in this survey participated in the Korean Rural Genomic Cohort (KRGC) study. Written consent was obtained from the local ethical committee. Of these participants, 1437 were men (mean age 56.9 +/- 7.9 years) and 2071 were women (mean age 55.8 +/- 8.1 years). We measured GGT levels and various biochemical markers. To examine insulin resistance status, we used the homeostasis assessment method for insulin resistance (HOMA-IR). For inflammatory marker, we used C-reactive protein (CRP) levels. RESULTS: Serum GGT levels were significantly higher in the MS group compared to the healthy patient group [23 (5-1403) vs. 19 (5-1920) IU/l; P = 0.01]. The prevalence of MS and adjusted relative risk were both significantly increased from the lowest to highest GGT quartiles; these results persisted after adjustments for multiple confounders. Positive correlations were established between GGT and HOMA-IR or CRP. CONCLUSION: These results suggest that GGT levels may be a surrogate marker of insulin resistance, inflammation and MS.


Asunto(s)
Glucemia/metabolismo , Proteína C-Reactiva/metabolismo , Síndrome Metabólico/enzimología , gamma-Glutamiltransferasa/metabolismo , Adulto , Biomarcadores/metabolismo , Índice de Masa Corporal , Femenino , Humanos , Resistencia a la Insulina/etnología , Resistencia a la Insulina/fisiología , Masculino , Persona de Mediana Edad , Obesidad/etnología , Obesidad/metabolismo
11.
Bioresour Technol ; 98(1): 165-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16387491

RESUMEN

The molecular weight of exo-biopolymer obtained from a submerged culture of Cordyceps sinensis 16 consisted of a main unit and a subunit of 126 and 68 kDa, respectively. The optimal medium for the production of mycelia and exo-biopolymer was determined to be molasses containing 2% sucrose, 0.9% yeast extract, 0.3% K2HPO4, and 0.4% CaCl2. Using optimized medium, maximum productions of mycelia and exo-biopolymer in shake-flask culture were 54.0 g/L and 28.4 g/L, respectively. This study suggests that large-scale production of mycelia and exo-biopolymer by C. sinensis 16 is possible in submerged culture.


Asunto(s)
Biopolímeros/metabolismo , Cordyceps/metabolismo , Melaza , Micelio/crecimiento & desarrollo , Medios de Cultivo , Factores de Tiempo
12.
J Dent Res ; 96(12): 1414-1421, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28665757

RESUMEN

We recently reported the presence of anti-aquaporin 5 (AQP5) immunoglobulin G (IgG) in patients with primary Sjögren syndrome (SS) with a sensitivity of 0.73 and a specificity of 0.68. The aim of this study was to identify functional epitopes for the anti-AQP5 autoantibodies detected in control subjects and patients with SS. Recognition of epitopes by anti-AQP5 autoantibodies in sera ( n = 13 for control and n = 24 for SS) or purified IgG ( n = 1 for control and n = 3 for SS) was evaluated by indirect immunofluorescence (IIF) assay performed in the presence or absence of peptides corresponding to the second transmembrane helix and extracellular loops A, C, and E of AQP5. Functional epitopes were determined by measuring the effects of purified IgG and neutralizing peptides on transepithelial osmotic permeability (PfT) of MDCK cells expressing AQP5. In the IIF assay, 89% of SS samples were inhibited by at least 1 peptide, while only half of control samples were inhibited by any peptide. Overall, SS samples were inhibited by peptides corresponding to extracellular loops A, C, and E by 40% to 50%, whereas control samples were inhibited only by peptides corresponding to loop E by <20%. A cyclized peptide (E1) mimicking loop E was most frequently recognized and best differentiated between the SS and control samples. Incubation of MDCK-AQP5 cells with SS but not with control IgG, significantly decreased PfT, which was reversed by neutralization of IgG binding to any of the extracellular loops. In conclusion, the anti-AQP5 autoantibodies detected in control and SS groups showed differences in fine specificity to the functional epitopes of AQP5. The prevalent recognition of functional epitopes by anti-AQP5 autoantibodies from SS patients suggests that anti-AQP5 autoantibodies act as mediators of glandular hypofunction and are a potential therapeutic target in SS.


Asunto(s)
Acuaporina 5/antagonistas & inhibidores , Epítopos/inmunología , Síndrome de Sjögren/inmunología , Secuencia de Aminoácidos , Autoanticuerpos/inmunología , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunoglobulina G/inmunología , Péptidos/inmunología
13.
Org Lett ; 2(16): 2487-90, 2000 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-10956528

RESUMEN

Ketones were asymmetrically transformed to chiral acetates by one-pot processes using a lipase and an achiral ruthenium complex under 1 atm of hydrogen gas in ethyl acetate. Molecular hydrogen was also effective for the transformation of enol acetates to chiral acetates without additional acyl donors with the same catalyst system.


Asunto(s)
Acetatos/química , Acetatos/síntesis química , Cetonas/química , Lipasa , Rutenio , Indicadores y Reactivos , Isomerismo , Relación Estructura-Actividad
14.
Org Lett ; 3(8): 1233-6, 2001 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-11348202

RESUMEN

[reaction: see text]. Catalysis of the glyoxylate-ene reaction by dicationic P2Pt(II) complexes is subject to anion-dependent additive effects. For [((S)-MeOBiphep)Pt](OTf)2 catalysts, acidic phenols such as 3-CF3-C6H3OH or C6F5OH provide substantial rate increases but do not affect the more active SbF6-based catalysts. Enantioselectivity and reactivity also increased with diphosphine basicity, with 4-t-Bu-substituted MeOBiphep ligands yielding the highest enantioselectivities.


Asunto(s)
Fosfinas/química , Platino (Metal)/química , Aniones , Iones , Ligandos , Modelos Químicos , Fenol/química
15.
Org Lett ; 2(15): 2377-9, 2000 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-10930288

RESUMEN

An enzyme-metal combo reaction has been developed for the dynamic kinetic resolution of allylic alcohols in which racemic substrates are transformed by a lipase and a ruthenium complex in the presence of an acyl donor to allylic acetates of high optical purity in over 80% yield.


Asunto(s)
Lipasa/metabolismo , Propanoles/síntesis química , Compuestos de Rutenio/metabolismo , Catálisis , Enzimas Inmovilizadas/metabolismo , Cinética , Propanoles/química , Propanoles/metabolismo , Pseudomonas/enzimología , Estereoisomerismo
16.
J Chromatogr A ; 796(1): 41-57, 1998 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-9513281

RESUMEN

The axial homogeneity of preparative-scale chromatography columns was studied by measuring the overall properties of similar columns differing only by their lengths. The properties investigated were the packing density, the external porosity, the permeability and the column efficiency. Two different materials were used, one made of large, irregular silica particles compressed under either high or a low degree of stress; the other of small, spherical and rigid particles. The columns made with the spherical particles were more homogeneous, had a higher external porosity and specific permeability, and a higher efficiency than those made with the irregular ones. For this latter material, the columns prepared with a low level of stress were better than those compressed under high stress. The latter ones experienced extensive particle breakage. These results indicate that the long columns are heterogeneous in their axial direction.


Asunto(s)
Cromatografía Liquida/métodos , Microesferas , Tamaño de la Partícula , Permeabilidad , Porosidad , Estrés Mecánico
17.
J Chromatogr A ; 762(1-2): 83-8, 1997 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-9098968

RESUMEN

A variety of complementary evidence reviewed here demonstrates that the packing of chromatographic columns is heterogeneous. It is denser and less well organized close to the column wall than in the center of the column. The mechanism of particle consolidation under stress explains the origin of this phenomenon and provides a fundamental justification to what is known in column chromatography as "the wall effect".


Asunto(s)
Cromatografía Liquida/métodos , Resinas Sintéticas/química , Propiedades de Superficie
18.
Int J Clin Pharmacol Ther ; 39(12): 539-45, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11770835

RESUMEN

OBJECTIVE: To comparre the safety and efficacy of naproxen CR (1,000 mg once daily) with that of nabumetone (1,000 mg once daily) in the treatment of patients with symptomatic knee osteoarthritis(OA). METHODS: A total of 159 Korean patients (80 in the naproxen CR group and 79 in the nabumetone group) were enrolled in this 4-week, single-blind, controlled, randomized, parallel study and an intention-to-treat model was used for data analysis. Six efficacy parameters were measured: Lequesne index, visual analogue pain scale at rest and atactivity, patient's and physician's global assessment, and time to walk 50 feet. RESULTS: Significant improvement in all efficacy parameters except time to walk 50 feet occurred at Week 2 and Week 4 in both groups. Themean improvement from baseline at Week 2 and Week 4 for the efficacy variables was not different between naproxen CR and nabumetone group. Twenty-four patients (30%) in the naproxen CR group and 18 patients (22.8%) in the nabumetone group withdrew from the study. Among them, only 1patient in the naproxen CR group terminated the study prematurely due to an adverse event of dyspepsia. No statistically significant difference in the frequency of adverse events, including gastrointestinal symptoms, was observed between these 2 groups during the treatment period. Significant laboratory abnormalities also did not occur during the study period in both groups. CONCLUSIONS: Naproxen CR is an effective and tolerable drug in the treatment of knee OA. Efficacy and safety profiles are comparable to those of nabumetone.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Butanonas/uso terapéutico , Naproxeno/uso terapéutico , Osteoartritis de la Rodilla/tratamiento farmacológico , Actividades Cotidianas , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Butanonas/administración & dosificación , Butanonas/efectos adversos , Estreñimiento/inducido químicamente , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nabumetona , Naproxeno/administración & dosificación , Naproxeno/efectos adversos , Náusea/inducido químicamente , Dimensión del Dolor , Método Simple Ciego , Resultado del Tratamiento , Caminata
19.
Clin Nucl Med ; 24(7): 495-500, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10402001

RESUMEN

PURPOSE: An accurate, preoperative assessment of tumor extent and lymph node involvement is necessary to plan and tailor therapy for patients with head and neck cancer. Metabolic imaging with fluorine-18 fluorodeoxy-glucose (FDG) is a good method to detect primary tumors in the head and neck and to assess the involvement of lymph nodes, but it is not widely available because of the high cost of positron emission tomography (PET). Recently, an alternative method for using FDG was developed: coincidence detection PET (CoDe PET) using a gamma camera. The aim of this study was to evaluate the clinical utility of FDG CoDe PET using a gamma camera in patients with head and neck cancer. MATERIALS AND METHODS: Thirty FDG CoDe PET studies without attenuation correction were performed in seven patients before therapy and in 19 patients after therapy (ages: 25-79 years, mean, 50 +/- 13 years; 18 men, 8 women) with various head and neck cancers. All patients had fasted for 6 to 12 hours and were injected with 111 to 370 MBq F-18 FDG 1 hour before imaging. Visually detectable focal FDG uptake in the primary tumor site or in the neck was considered positive except for physiologic uptake. The FDG CoDe PET studies were correlated with MRI. The gold standard for the presence of disease was the combination of repeated MRIs, endoscopic examination, and 3 months of follow-up clinical evaluation. RESULTS: FDG CoDe PET had a detection rate that was comparable to that of MRI in the pretherapy group. However, in the posttherapy group, FDG CoDe PET could differentiate residual tumor or tumor recurrence from radiation change more accurately than could MRI. However, it had a less accurate detection rate for cervical node metastases because of asymmetric neck muscle uptake. CONCLUSIONS: FDG CoDe PET is a sensitive and cost-effective method to detect primary tumor and lymph node involvement in primary head and neck cancers. It is also useful in differentiating residual tumor or tumor recurrence from posttherapy changes in patients with head and neck tumors.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Metástasis Linfática/diagnóstico por imagen , Tomografía Computarizada de Emisión/métodos , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Cámaras gamma , Cabeza/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/terapia , Humanos , Procesamiento de Imagen Asistido por Computador , Ganglios Linfáticos/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Cuello/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasia Residual/diagnóstico por imagen , Radiofármacos/farmacocinética , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión/economía , Tomografía Computarizada de Emisión/instrumentación
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