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OBJECTIVES: Whereas antinuclear antibodies (ANAs) detected by indirect immunofluorescence (IIF) have diagnostic significance, the dense fine speckled (DFS) pattern on HEp-2 cells may be an exclusionary marker for ANA-associated rheumatic disease (AARD). The aim of this study was to evaluate a new algorithm considering anti-DFS70 antibodies for routine ANA testing. METHOD: From ANA requested sequential 10 528 sera, 181 sera samples showing the DFS pattern were additionally tested for anti-DFS70 antibodies by an enzyme-linked immunosorbent assay (ELISA-DFS70) and for specific-ANAs. Specific-ANAs(+)/IIF-DFS(-) control sera samples (n = 50) were also tested. RESULTS: Of the 181 IIF-DFS-positive sera samples, 82.9% (n = 150) were from non-AARD patients and 112 (61.9%) patients had non-rheumatic diseases (NRD), including the most common clinical feature of dermatitis (18.2%). The ELISA-DFS70 was positive in 109 (60.2%) sera and was negative in all control sera. Specific-ANAs were similarly detected as 25.7% (28/109) and 22.2% (16/72) of ELISA-DFS70(+) and ELISA-DFS70(+) patients, respectively (p > 0.05). The prevalence of non-AARD was 95.1% and 25.1% in the ELISA-DFS70(+)/specific-ANAs(-) and ELISA-DFS70(-)/specific-ANAs (+) groups, respectively. CONCLUSIONS: In patients with a HEp-2 DFS pattern, the additional ELISA-DFS70 and specific-ANAs test could improve the efficiency of diagnosing AARD. The detection of anti-DFS70 antibodies should be included in test algorithms for ANA testing.
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Proteínas Adaptadoras Transductoras de Señales/inmunología , Algoritmos , Anticuerpos Antinucleares/inmunología , Enfermedades del Tejido Conjuntivo/inmunología , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Síndrome de Sjögren/inmunología , Factores de Transcripción/inmunología , Autoanticuerpos/inmunología , Línea Celular Tumoral , Enfermedades del Tejido Conjuntivo/diagnóstico , Dermatomiositis/diagnóstico , Dermatomiositis/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoensayo , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/inmunología , Enfermedad Mixta del Tejido Conjuntivo/diagnóstico , Enfermedad Mixta del Tejido Conjuntivo/inmunología , Enfermedades Reumáticas/diagnóstico , Enfermedades Reumáticas/inmunología , Esclerodermia Sistémica/diagnóstico , Esclerodermia Sistémica/inmunología , Sensibilidad y Especificidad , Síndrome de Sjögren/diagnósticoRESUMEN
INTRODUCTION: The main goal of this study was to develop a multiparametric cell population data (CPD) model that combines information from several morphologic parameters generated by DxH800, in addition to the traditional parameters regularly reported in the CBC-diff, and to test the performance of this model in screening the general population for primary tuberculosis (TB). METHODS: A total of 3741 study cases were divided into two groups, test and validation set at cut-off value of 6000 WBCs/µL. We developed multiparametric model for primary TB screening (TB hemeprint), selected CPD, and calculated parameters which could discriminate primary TB from other non-TB diseases and normal control in test set. We applied it to the validation set, which was a set of completely different samples, to test its reproducibility if applied to a routine laboratory test. RESULTS: After screening primary TB using TB hemeprint, sensitivity, specificity, PPV, and NPV were 85.4%, 89.6%, 31.1%, and 99.1%, respectively, in primary TB with lower than 6000 WBCs/µL of test set (test set-L). In primary TB with higher than 6000 WBCs/µL of test set (test set-H), those values were 83.1%, 85.6%, 29.7%, and 98.6%, respectively. There were only 0.4% (2/461) and 0.6% (2/326) of normal control samples included in test set-L and -H, respectively. Diagnostic efficiencies except sensitivity in each validation set were very comparable with those in each test set. CONCLUSION: Tuberculosis hemeprint may allow us to screen primary TB with acceptable sensitivity and specificity using combination of TB-specific CPD and calculated parameters.
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Recuento de Células Sanguíneas , Tuberculosis/sangre , Tuberculosis/diagnóstico , Recuento de Células Sanguíneas/métodos , Recuento de Células Sanguíneas/normas , Índices de Eritrocitos , Humanos , Tamizaje Masivo , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
INTRODUCTION: Plasmodium vivax malaria is one of the most important infectious diseases plaguing humanity and causes significant mortality and morbidity worldwide. The gold standard of P. vivax malaria diagnosis is the microscopy of blood smears. Although microscopy is a rapid, cost-effective, and readily applicable method, it has many disadvantages, including low sensitivity, specificity, and precision. Therefore, there is a clear need for an effective screening test for P. vivax malaria detection both in high-prevalence areas and developed countries. METHODS: A total of 1761 complete blood count (CBC) samples generated by the automated hematology analyzer (DxH 800™; Beckman Coulter Inc., Miami, FL, USA) were retrospectively analyzed. The sample pool contained 123 samples from 52 P. vivax malaria patients and 1504 nonmalarial samples including 509 patients with leukopenia (white blood cell <2000/µL) and 134 normal subjects. RESULTS: The P. vivax malaria samples exhibited easily recognizable typical malaria signals on the nucleated red blood cell (nRBC) plots (sensitivity 100%) in DxH 800™. All 1504 samples without P. vivax infection were negative for malaria signal (specificity 100%). The size of P. vivax malaria signals correlated roughly with the parasite burden. CONCLUSION: DxH800™ provides very sensitive and specific, easily recognizable P. vivax malaria signals on routine CBC without need for the additional reagents or special procedures.
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Recuento de Células Sanguíneas/instrumentación , Malaria Vivax/diagnóstico , Carga de Parásitos/métodos , Plasmodium vivax/aislamiento & purificación , Recuento de Células Sanguíneas/métodos , Humanos , Carga de Parásitos/instrumentación , Sensibilidad y EspecificidadRESUMEN
INTRODUCTION: We determined the utility of leukocyte cell population data (CPD) for the screening of sepsis and fungemia. METHODS: Blood culture-positive CBC samples, 117 bacteremia and 27 fungemia, and 134 CBC samples from healthy controls were analyzed using the DxH800 and CPD of neutrophils, lymphocytes, and monocytes were analyzed. Immature granulocytes (IG) were counted using Sysmex XE-2100. RESULTS: The neutrophils and monocytes volume were increased significantly, and the neutrophils light scattering values were reduced significantly in the sepsis samples. ROC curves evidenced excellent sensitivity in the lymphocyte SD parameters (sensitivity 78-89%, specificity 78-87%), monocytes volume (at 177.5, sensitivity 88.2% specificity 87.3%), and monocytes volume SD (at 22.16, sensitivity 93.1% specificity 91.0%) for sepsis. The IG value was significantly higher in sepsis and the ROC curve evidenced a sensitivity of 82.8% and a specificity of 90.8% for sepsis. Only lower angle light scatter of lymphocytes SD value evidenced good sensitivity and specificity in the discrimination of fungemia from bacteremia (sensitivity 74.1%, specificity 72.4% at 12.6). CONCLUSION: Many of the leukocyte CPD have been identified as useful parameters of sepsis. Hopefully, these parameters can ultimately be incorporated into a decision rule for the screening of sepsis samples and to discriminate fungemia from bacteremia.
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Fungemia/diagnóstico , Recuento de Leucocitos/instrumentación , Tamizaje Masivo/instrumentación , Sepsis/diagnóstico , Automatización , Bacterias/aislamiento & purificación , Recuento de Células Sanguíneas/instrumentación , Hongos/aislamiento & purificación , Humanos , Leucocitos/patología , Tamizaje Masivo/métodosRESUMEN
Corn starch was converted using alpha-1,4-glucanotransferase from Thermotoga maritima (Tm alpha GT), a hyperthermophilic bacterium, without inducing gelatinization, and the structural changes and physical properties of the modified starches were investigated. Enzyme modification was induced at 65 degrees C for 8, 16, or 24 h, and the morphology of the modified starches was observed with light and scanning electron microscopy. Granule integrity was mostly maintained after enzyme treatment, although some granules were partially fragmented as evidenced by enlarged surface pores and some cracks. The modified starches had lower apparent amylose levels than raw starch. The molecular weights of amylose and amylopectin molecules in the treated starches were lower than those of raw starch, and the amount of branched molecules, which had much lower molecular weights, also increased in the treated starches. The chain-length distribution of amylopectin showed an increased number of shorter branched chains. The modified starches showed a wider melting temperature range and a lower melting enthalpy than that of raw starch. The X-ray diffraction pattern of the modified starches showed typical A-type starch peaks, but the relative crystallinities were lower than that of raw starch. The solubility and paste clarity of the modified starches were much higher than those of raw starch. The modified starch gels maintained their rigidity over the whole frequency range tested and showed thermoreversibility between 4 and 75 degrees C. These results suggest that Tm alpha GT can be used to produce granular corn starch, which contains amylose and amylopectin having lower molecular weights and a thermoreversible gelation property.
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Amilopectina/química , Amilosa/química , Sistema de la Enzima Desramificadora del Glucógeno/metabolismo , Almidón/química , Thermotoga maritima/enzimología , Zea mays/química , Rastreo Diferencial de Calorimetría , Fraccionamiento Químico , Fenómenos Químicos , Química Física , Cromatografía por Intercambio Iónico , Microscopía Electrónica de Rastreo , Estructura Molecular , Peso Molecular , Tamaño de la Partícula , Solubilidad , Almidón/ultraestructura , Temperatura , Factores de Tiempo , Difracción de Rayos XRESUMEN
Interferon (IFN)-gamma enzyme-linked immunosorbent spot (ELISPOT) assay is a powerful tool for measuring the frequency of alloantigen-specific T cells, reflecting cellular immunity. We correlated the pretransplant frequencies of donor-specific and third-party-specific IFN-gamma ELISPOT tests, with the posttransplant outcomes of 45 recipients of living donor renal transplantations. The mean frequency of pretransplant donor-specific ELISPOT was significantly greater among patients with acute rejection episodes (ARE) than those without ARE (18.0 [12 to 50] versus 8.8 [5 to 30.4]) spots per 200,000 peripheral blood lymphocytes (PBLs; P=.024). A cutoff level of 12 spots per 200,000 PBLs on the donor-specific ELISPOT identified an ARE-positive patient with a sensitivity of 81.8% and a specificity of 64.7%. The recipients with pretransplant donor-specific ELISPOT+showed higher serum creatinine levels and lower glomerular filtration rate (GFR) at 6 posttransplant months (P<.05). Although the pretransplant third-party-specific ELISPOT results correlated with the donor-specific ELISPOT results (r=.783; P<.001), there was no significant difference in the third-party ELISPOT results between the ARE-positive and ARE-negative recipients. In conclusion, an analysis of pretransplant donor-specific IFN-gamma ELISPOT may identify the posttransplant risk of developing ARE and displaying decreased GFR at 6 months.
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Rechazo de Injerto/patología , Interferón gamma/sangre , Trasplante de Riñón/patología , Adulto , Biomarcadores/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Rechazo de Injerto/inmunología , Humanos , Isoantígenos/inmunología , Trasplante de Riñón/inmunología , Donadores Vivos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Linfocitos T/inmunologíaRESUMEN
Hyperparathyroidism may be a precipitating factor important to the development of myelofibrosis: however, there has been only a few reports regarding myelofibrosis secondary to primary hyperparathyroidism. Recently, a rare case of pancytopenia caused by myelofibrosis in a 41-year-old woman who complained of general weakness and arthralgia presented to our clinical service. The patient was diagnosed with primary hyperparathyroidism with pancytopenia. Bone marrow biopsy revealed myelofibrosis. Right parathyroidectomy was performed and a parathyroid adenoma was totally excised. After surgery, the CBC counts and other clinical abnormalities gradually improved without further intervention. We concluded that the pancytopenia was because of bone marrow fibrosis resulting from primary hyperparathyroidism. Therefore, physicians should consider myelofibrosis secondary to primary hyperparathyroidism as a cause of pancytopenia in hypercalcemic patients, even though it is rare.
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Hiperparatiroidismo/complicaciones , Pancitopenia/etiología , Neoplasias de las Paratiroides/complicaciones , Mielofibrosis Primaria/etiología , Adulto , Femenino , Humanos , Hiperparatiroidismo/patología , Hiperparatiroidismo/cirugía , Pancitopenia/patología , Pancitopenia/cirugía , Neoplasias de las Paratiroides/patología , Neoplasias de las Paratiroides/cirugía , Mielofibrosis Primaria/patología , Mielofibrosis Primaria/cirugíaRESUMEN
This study evaluated the accuracy of cefotetan susceptibility determination using the MicroScan WalkAway system for AmpC-producing Klebsiella pneumoniae. In total, 57 K. pneumoniae isolates that showed a D-shape flattening in a double-disk synergy test were studied. Cefotetan MICs were determined by the agar dilution method. The bla(DHA) gene was detected in all 57 isolates, one of which co-harboured bla(CMY-1). According to the MicroScan system, 28 isolates were susceptible, 18 were intermediately-resistant, and 11 were resistant to cefotetan. Compared with the agar dilution method, very major, minor and major error rates were 28.1% (16/57), 47.4% (27/57) and 1.8% (1/57), respectively.
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Antibacterianos/farmacología , Cefotetán/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/instrumentación , Resistencia betalactámica/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Reacciones Falso Positivas , Humanos , Pruebas de Sensibilidad Microbiana/métodos , beta-Lactamasas/genética , beta-Lactamasas/metabolismoRESUMEN
The antibody monitoring system (AMS, GTI Inc) is a solid enzyme-linked immunosorbent assay (ELISA) crossmatch test for the detection of immunoglobulin G (IgG) antibody to donor-specific solubilized HLA class I and class II antigens. The objective of this study was to compare the results of the AMS assay with donor-specific anti-HLA IgG antibodies (DS-HLA Abs), as determined by ELISA panel reactive antibody (PRA) and the flow cytometric crossmatch test (FCXM). A total of 107 sera were screened for the presence of HLA Abs by ELISA PRA (LAT-M, One-Lambda Inc), the DS-HLA Abs were determined in 34 serum samples (31.8%) by an ELISA panel (LAT class I and class II, One-Lambda Inc) and FCXM. The FCXM and AMS assays were performed with matched lymphocytes from 56 donors. There was a significant degree of concordance (89.7%) between the two tests (P < .001). The sensitivity, specificity, positive predictive value, and negative predictive value of AMS assay to detect DS-HLA Abs was 88.2%, 94.5%, 88.2%, and 94.5%, respectively. The AMS is a simple, objective test, which has several advantages over the cell-based crossmatch test, such as elimination of non-HLA antibody reactivity, elimination of non-donor-specific antibody reactivity, no need for viable cells, and preparation of the donor's HLA antigens in advance. In summary, this study suggested that AMS may be useful as a supportive crossmatch test or as a monitoring test after transplantation to detect class I or class II DS-HLA Abs.
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Antígenos HLA-D/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Isoanticuerpos/sangre , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G/sangre , Trasplante de Riñón/inmunología , Monitorización Inmunológica/métodos , Listas de EsperaRESUMEN
The aim of the present study was to identify whether the serum interferon-gamma (IFNgamma), a Th1 cytokine, or soluble CD30 (sCD30), a marker for activation of Th2 cytokine-producing T cells, predict acute cellular rejection episodes among liver graft patients. Pretransplant and posttransplant sera from 32 living donor liver transplant recipients obtained on days 1, 3, and 7 after surgery were tested for serum IFNgamma and sCD30 concentrations using commercial enzyme-linked immunosorbent assay kits. Recipients with an acute rejection episode (ARE) (n=14) displayed significantly higher IFNgamma concentrations pretransplant than did the patients with no ARE (n=18) (P<.05). The pretransplant serum levels of sCD30 were not different between the non-ARE and ARE groups. However, in comparison with the non-ARE group, who showed steadily decreasing serum sCD30 levels after transplantation, 12 among the 14 patients in the ARE group showed increasing sCD30 levels from day 1 to day 3 after transplantation (P<.05). These results suggest that the sCD30 increment during the early period after liver transplantation affects the immune response of rejection. This observation emphasizes the clinical relevance of serum sCD30, in addition to serum IFNgamma, as predictive markers for acute liver graft rejection.
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Rechazo de Injerto/epidemiología , Interferón gamma/sangre , Antígeno Ki-1/sangre , Trasplante de Hígado/inmunología , Células Th2/inmunología , Antígenos CD/sangre , Biomarcadores/sangre , Rechazo de Injerto/inmunología , Humanos , Donadores Vivos , Periodo Posoperatorio , Cuidados Preoperatorios , Estudios RetrospectivosRESUMEN
We present a case of Epstein-Barr virus (EBV)-associated haemophagocytic syndrome in a patient with Behçet's disease. A 43-year-old man, who had been receiving treatment under the diagnosis of Behçet's disease for recurrent oral ulcers, genital ulcer, ileal ulcer, and arthritis, had been admitted for fever, headache, and nausea developed 3 days ago. Laboratory data showed pancytopaenia, an increase in liver enzymes, lactate dehydrogenase (LDH) and ferritin. Haemophagocytic syndrome was diagnosed from histiocytosis and haemophagocytosis by macrophages, shown in the bone marrow aspiration and biopsy, and in situ hybridization for EBV showed a positive finding. The patient recovered rapidly after steroid therapy. This is the first report of EBV-associated haemophagocytic syndrome developed in a patient with Behçet's disease.
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Síndrome de Behçet/complicaciones , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4/aislamiento & purificación , Histiocitosis de Células no Langerhans/complicaciones , Adulto , Antibacterianos/uso terapéutico , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamiento farmacológico , Células de la Médula Ósea/citología , Ciclosporina/uso terapéutico , Quimioterapia Combinada , Infecciones por Virus de Epstein-Barr/diagnóstico , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Estudios de Seguimiento , Histiocitosis de Células no Langerhans/diagnóstico , Histiocitosis de Células no Langerhans/tratamiento farmacológico , Humanos , Masculino , Prednisolona/uso terapéutico , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
Activation of any of the three known tachykinin receptors (NK1R, -2R, or -3R) can cause a rise in [Ca2+]i via a pertussis toxin-insensitive heterotrimeric G protein, Gq/G11, activation of phospholipase C (PLC), and a membrane depolarization. Tachykinins can depolarize neurons by two distinct mechanisms: 1) they reduce a resting K+ current in many neurons or 2) in parasympathetic and vagal primary sensory neurons, they activate a nonspecific cation current (Icat). Transient receptor potential channels (TRPC) are nonspecific cation channels that can be activated by a rise in [Ca2+]i in a PLC-dependent manner. The present work tests whether NK2R can signal TRPC. We applied standard whole cell patch-clamp recordings to HEK293 cells stably transfected with the human TRP3 channels (TRP3C), and transiently transfected with a functional NK2R-EGFP. Bath applied Substance P (SP, 1 microM) induced an Icat in the cells expressing both TRP3C and NK2R. Icat reached its peak value in approximately 3 min (195 +/- 120.0 s, mean +/- SE, n = 20), had a peak density of 11.3 +/- 3.48 pA/pF (n = 24), and was blocked by an NK2R-specific antagonist (SR48968, 100 nM). The Erev value for the SP current was 6.8 +/- 7.66 mV (n = 6), suggestive of a nonspecific cation channel. Icat was not measurable in TRP3C-expressing HEK293 cells without NK2R expression (n = 6) or in wild-type HEK293 cells with NK2R expression (n = 12). These data indicate that NK2R can be functionally coupled to TRP channels in HEK293 cells and suggest that SP-induced cation currents in vagal primary sensory neurons might be mediated by TRPC.
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Canales de Calcio/fisiología , Sustancia P/farmacología , Cationes , Línea Celular , Humanos , Canales Iónicos/fisiología , Receptores de Neuroquinina-2/fisiología , Canales Catiónicos TRPCRESUMEN
Low moisture part-skim Mozzarella cheeses (MC) were manufactured using fresh bovine and caprine milk to study melting, physico-chemical, textural, and microstructural properties of the cheeses during 8 wk of refrigerated storage. Structural changes in cheese matrix were evaluated by scanning electron microscopy and by proteolytic patterns using nitrogen solubility, SDS-PAGE, and Gel-pro analyzer. Meltability of ripened cow and goat MC were not different when fat content of both milks were standardized, whereas bovine MC formed a significantly larger amount of free oil throughout the experiment. The results of the proteolytic patterns, texture attribute (cohesiveness), and microstructure revealed that bovine MC had a greater structural degradation of cheese matrix than caprine MC during the storage. Elevated protein degradation in bovine MC led to more intense brown color formation than the goat counterpart when the cheeses were baked. The melting characteristics showed high positive correlation (r = 0.51 to 0.80) with proteolysis, whereas it was negatively correlated with textural characteristics. Among textural attributes, cohesiveness was highly inversely correlated with melting characteristics (r = -0.69 to -0.88). High negative correlations were also observed between proteolytic parameters and textural attributes (r = -0.48 to -0.81).
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Bovinos , Queso/análisis , Frío , Conservación de Alimentos , Cabras , Animales , Fenómenos Químicos , Química Física , Endopeptidasas/metabolismo , Lípidos/análisis , Reacción de Maillard , Microscopía Electrónica de Rastreo , Proteínas de la Leche/análisis , Proteínas de la Leche/metabolismo , Nitrógeno/análisis , Reología , SolubilidadRESUMEN
We have identified a new HLA-B*15 allele and a new HLA-DRB1*12 allele, named B*1568 and DRB1*1208, respectively. The alleles were identified using a combination of sequence specific primers, reverse line sequence specific oligonucleotide probing and sequence-based typing. Both alleles were identified in a single individual of Korean origin. HLA-B*1568 appears to be an HLA-B*4801/B*1507 hybrid combining the exon 2 sequence of B*4801 and the exon 3 and 4 sequences of B*1507. Exon 2 of DRB1*1208 was most similar to DRB1*1201 or 1206, with a single mismatch at nucleotide position 165 (A to C). At the protein level, this substitution results in a phenylalanine substitution at position 26 that creates an identical amino acid sequence to DRB3*0202 between amino acid positions 17 and 36.
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Antígenos HLA-B/genética , Antígenos HLA-DR/genética , Secuencia de Aminoácidos , Exones , Antígeno HLA-B15 , Cadenas HLA-DRB1 , Humanos , Corea (Geográfico) , Datos de Secuencia MolecularRESUMEN
DNA-dependent protein kinase (DNA-PK) is composed of a 460-kDa catalytic subunit and the regulatory subunits Ku70 and Ku80. The complex is activated on DNA damage and plays an essential role in double-strand-break repair and V(D)J recombination. In addition, DNA-PK is involved in S-phase checkpoint arrest following irradiation, although its role in damage-induced checkpoint arrest is not clear. In an effort to understand the role of DNA-PK in damage signaling, human and mouse cells containing the DNA-PK catalytic subunit (DNA-PKcs proficient) were compared with those lacking DNA-PKcs for c-Jun N-terminal kinase (JNK) activity that mediates physiologic responses to DNA damage. The DNA-PKcs-proficient cells showed much tighter regulation of JNK activity after DNA damage, while the level of JNK protein in both cell lines remained unchanged. The JNK proteins physically associated with DNA-PKcs and Ku70/Ku80 heterodimer, and the interaction was significantly stimulated after DNA damage. Various JNK isoforms not only contained a DNA-PK phosphorylation consensus site (serine followed by glutamine) but also were phosphorylated by DNA-PK in vitro. Together, our results suggest that DNA damage induces physical interaction between DNA-PK and JNK, which may in turn negatively affect JNK activity through JNK phosphorylation by DNA-PK.
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Proteínas de Unión al ADN , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Estrés Fisiológico/enzimología , Animales , Línea Celular , Daño del ADN , Reparación del ADN , Proteína Quinasa Activada por ADN , Activación Enzimática , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos , Ratones , Proteína Quinasa 10 Activada por Mitógenos , Proteína Quinasa 8 Activada por Mitógenos , Proteína Quinasa 9 Activada por Mitógenos , Proteínas Nucleares , Fosforilación , Proteínas Tirosina Quinasas/metabolismoRESUMEN
The prevalence of low-level resistance to glycopeptides (teicoplanin MIC > or = 8 microg/mL and vancomycin MIC > or = 4 microg/mL) among staphylococci was investigated over a 15 month period. A total of 2,279 isolates (1,519 S. aureus, 760 coagulase-negative staphylococcus (CNS)) were screened using inoculum of 10(6) CFU/mL and Mueller-Hinton agars supplemented with 8 microg/mL of teicoplanin. Of these, 218 isolates (136 S. aureus and 82 CNS) grew on the screening agar. For these isolates, teicoplanin and vancomycin MICs were determined by agar dilution method and a vancomycin agar screening method was evaluated. The prevalence of low-level resistance to teicoplanin and vancomycin was 7.8% and 0.1% for S. aureus and 8.8% and 0.8% for CNS, respectively. The brain heart infusion agar containing 4 microg/mL of vancomycin failed to detect two out of eight staphylococcal isolates with vancomycin MICs of 4 microg/mL. Furthermore, the method appeared to lack reproducibility. Considering the increasing incidence of vancomycin treatment failure in staphylococcal infection, a more reliable screening method is required.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Hospitales Universitarios , Staphylococcus aureus/efectos de los fármacos , Staphylococcus/efectos de los fármacos , Teicoplanina/farmacología , Resistencia a la Vancomicina , Vancomicina/farmacología , Agar , Humanos , Pruebas de Sensibilidad Microbiana , Vigilancia de la Población , Infecciones Estafilocócicas/microbiología , Staphylococcus/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificaciónRESUMEN
Resistance to teicoplanin in clinical isolates of Staphylococcus aureus has increased in frequency. Detection is difficult due to heterogeneous phenotypes of these strains. Two mutations in pbp4 have recently been identified in glycopeptide resistant laboratory strains. We investigated to determine if these mutations could be used to screen clinical isolates for teicoplanin resistance. Of 41 clinical isolates screened, none contained the mutations in pbp4 indicating these mutations cannot be used as a molecular diagnostic tool for glycopeptide resistance.
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Antibacterianos/farmacología , Proteínas Bacterianas , Proteínas Portadoras/genética , Hexosiltransferasas , Muramoilpentapéptido Carboxipeptidasa/genética , Peptidil Transferasas , Staphylococcus aureus/efectos de los fármacos , Teicoplanina/farmacología , Análisis Mutacional de ADN , ADN Bacteriano/análisis , Farmacorresistencia Microbiana , Humanos , Pruebas de Sensibilidad Microbiana , Proteínas de Unión a las Penicilinas , Fenotipo , Reacción en Cadena de la Polimerasa , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificaciónRESUMEN
In this study, a combination of liquid and solid media (current "gold standard" for culture) with combinations of liquid media (Mycobacteria Growth Indicator Tube (MGIT)) plus a commercial amplification system (Roche COBAS AMPLICOR System (CAS)), and solid media (Ogawa) plus CAS for detection of Mycobacterium tuberculosis were compared. In addition, the ability of the MGIT to recover mycobacteria from various clinical samples was compared with the abilities of egg-based Ogawa medium using equal volume of samples and a high concentration (6%) of NaOH for decontamination. A total of 705 specimens (395 respiratory and 310 extrapulmonary) that were collected from 554 patients were tested in parallel with three assays. The results of MGIT and Ogawa were evaluated with the "gold standard" (combination of culture and clinical data) and those of CAS were evaluated with extended gold standard including treated tuberculosis. A total of 130 mycobacterial infections (M. tuberculosis, n=122; mycobacterium other than tuberculosis (MOTT), n=8) were detected. The differentiation of M. tuberculosis and MOTT was successfully accomplished using duplex PCR. The overall sensitivity of the MGIT, Ogawa, and CAS for M. tuberculosis was 89.9%, 73.9%, and 79.9%, respectively. For the MOTT, the corresponding values for the MGIT and Ogawa medium were 100% and 12.5%, respectively. The mean detection time for M. tuberculosis was 22 days using MGIT and 32 days when using the Ogawa medium. The specificity of CAS was 98.4%, with an inhibition rate of 1.4%. A combination of MGIT plus CAS detected 97.5% of all M. tuberculosis infections (compared with MGIT plus Ogawa, 91.8%, P<0.05; compared with Ogawa plus CAS, 87.7%. P<0.01). Our results indicate that a combination of MGIT plus a Roche CAS in conjunction with duplex PCR, would be quite useful in clinical laboratories for both rapid detection and differentiation of M. tuberculosis and MOTT.
Asunto(s)
Mycobacterium tuberculosis/clasificación , Tuberculosis Pulmonar/microbiología , Distribución de Chi-Cuadrado , Medios de Cultivo , Humanos , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Juego de Reactivos para Diagnóstico , Sensibilidad y EspecificidadRESUMEN
D-raf, a Drosophila homolog of the raf proto-oncogene, has diverse functions throughout development and is transcribed in a wide range of tissues, with high levels of expression in the ovary and in association with rapid proliferation. The expression pattern resembles those of S phase genes, which are regulated by E2F transcription factors. In the 5'-flanking region of D-raf, four sequences (E2F sites 1-4) similar to the E2F recognition sequence were found, one of them (E2F site 3) being recognized efficiently by Drosophila E2F (dE2F) in vitro. Transient luciferase expression assays confirmed activation of the D-raf gene promoter by dE2F/dDP. Expression of Draf-lacZ was greatly reduced in embryos homozygous for the dE2F mutation. These results suggest that dE2F is likely to be an important regulator of D-raf transcription.
Asunto(s)
Proteínas Portadoras , Proteínas de Ciclo Celular , Proteínas de Drosophila , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas Proto-Oncogénicas c-raf/genética , Transactivadores , Factores de Transcripción/metabolismo , Transcripción Genética/genética , Animales , Secuencia de Bases , Unión Competitiva , Sondas de ADN/genética , Sondas de ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción E2F , Embrión no Mamífero/metabolismo , Genes Reporteros/genética , Hibridación in Situ , Mutación/genética , Regiones Promotoras Genéticas/genética , Unión Proteica , ARN Mensajero/análisis , ARN Mensajero/genética , Proteínas Recombinantes de Fusión/metabolismo , Elementos de Respuesta/genética , Proteína 1 de Unión a Retinoblastoma , Factores de Transcripción/genética , Activación TranscripcionalRESUMEN
Previous studies have shown that dexamethasone, a synthetic glucocorticoid, can induce a G1 arrest, however, genistein, a natural isoflavonoid phytoestrogen, induces a G2/M arrest in the cell cycle progression in various cancer cell lines. A block of cell cycle checkpoint by dexamethasone and genistein correlates with a selective induction of cyclin-dependent kinase (Cdk) inhibitor p21WAF1/CIP1 in a tumor suppressor p53-independent manner and abolishment of Cdk2 phosphorylation. In the present study, the effects of dexamethasone and genistein (both singly and combined) on the expression of p21 in human hepatocellular Hep G2 and colorectal Colo320 HSR carcinoma cells were evaluated. Whereas dexamethasone mildly induced the level of p21 protein, genistein strongly increased the expression of p21 protein in our experimental condition. Both compounds also activated p21 promoter reporter constructs. The combined effects of dexamethasone and genistein on the induction of p21 protein and activation of p21 promoter were synergistic in both cell lines. These findings indicate that dexamethasone and genistein act in a synergistic fashion and have potential for combination chemotherapy for the treatment of liver and colon cancer.