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To detect the expression of galectin-13 in allergic diseases and provide a new way for the diagnosis and treatment of allergic diseases. A retrospective analysis method was used to screen 216 patients with allergic diseases with house dust mites or aspergillus as allergens who visited the Department of Allergy and Department of Respiratory of Tongji Hospital attached Tongji Medical College, Huazhong University of Science and Technology from March 2018 to May 2021. These allergic diseases included allergic asthma, allergic bronchopulmonary aspergillosis, allergic rhinitis, allergic conjunctivitis, atopic dermatitis, allergic urticaria. 25 subjects without underlying diseases were selected as healthy controls. The galectin-13 content in serum in each group were detected, and the Pearson correlation was used to determine the correlation between the galectin-13 content in serum in each group and blood eosinophil count, blood specific IgE, the score scale of allergic disease. The expression of Galectin-13 was increased in allergic asthma group (71.44±39.44) pg/ml, allergic bronchopulmonary aspergillosis group (100.10±47.62) pg/ml, allergic rhinitis group (54.11±24.81) pg/ml and dermatitis group (44.12±19.51) pg/ml. The expression of galectin-13 was not significantly increased in allergic urticaria group (32.75±10.29) pg/ml and the allergic conjunctivitis group (30.55±9.87) pg/ml. The galectin-13 content in serum, was positively correlated with blood eosinophil count(rs=0.54, P<0.001) and house dust mite specific IgE (rs=0.51, P<0.001) in allergic asthma group, and was positively correlated with blood eosinophil count(rs=0.63, P=0.025) and aspergillus fumigatus specific IgE (rs=0.58, P=0.046) in allergic bronchopulmonary aspergillosis group. It was positively correlated with blood eosinophil count (rs=0.52, P=0.000 2) and house dust mite specific IgE (rs=0.41, P=0.005) in allergic rhinitis group. In allergic conjunctivitis group, the expression of galectin-13 was positively correlated with conjunctivitis symptom score (rs=0.47, P=0.048). In atopic dermatitis group, the expression of galectin-13 was positively correlated with blood eosinophil count (rs=0.58, P<0.001) and house dust mite specificity IgE (rs=0.47, P=0.002). In allergic urticaria group, the expression of galectin-13 was not significantly correlated with blood eosinophil count or house dust mite specific IgE. Galectin-13 may be related to the occurrence and progress of allergic diseases and may be involved in the occurrence of eosinophilic inflammation.
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Aspergilosis Broncopulmonar Alérgica , Asma , Conjuntivitis Alérgica , Dermatitis Atópica , Rinitis Alérgica , Urticaria , Alérgenos , Galectinas , Humanos , Inmunoglobulina E/análisis , Membrana Mucosa/química , Proteínas Gestacionales , Estudios RetrospectivosRESUMEN
Objectives: This study aimed to evaluate the predictive value of the CHA2DS2-VASc score for in-hospital outcomes of patients with acute myocardial infarction (AMI). Methods: Data of 23 728 patients from the China patient-centered Evaluative Assessment of cardiac Events (China PEACE)Retrospective Acute Myocardial Infarction Study were analyzed retrospectively. The patients were categorized into 3 groups according to the CHA2DS2-VASc scores: the low score group (score 1-3), the middle score group (score 4-6) and the high score group (score 7-9). The in-hospital outcomes included major adverse cardiovascular events (MACE), death, death or withdrawal from treatment, reinfarction, ischemic stroke,etc. The CHA2DS2-VASc score was incorporated into multivariate Cox regression analyses to determine its independent impact on in-hospital outcomes. Receiver operating Characteristic (ROC) curves were constructed, and the area under the curve (AUC) was used to evaluate the predictive value of the CHA2DS2-VASc score for in-hospital mortality and death or withdrawal from treatment, respectively. Results: The patients had a median age of 66 (56,75) years, and 30.7% of them were females. Patients with higher CHA2DS2-VASc scores had a higher in-hospital mortality and more in-hospital complications (all P<0.001). After adjustment of baseline covariates, the subjects in the high score group were associated with high risks of in-hospital mortality (OR=6.13, 95%CI 4.77-7.87, P<0.001), death or treatment withdrawal (OR=6.43, 95%CI 5.16-8.00, P<0.001) and MACE (OR=4.94, 95%CI 4.06-6.01, P<0.001). The AUCs of the CHA2DS2-VASc score were comparable with those of the mini-global registry of acute coronary events(mini-GRACE)score in evaluation of in-hospital mortality (0.699 vs. 0.696, P=0.752) and the death or treatment withdrawal risk (0.708 vs. 0.713, P=0.489). Conclusions: The CHA2DS2-VASc score is an independent predictor of in-hospital outcomes for patients with AMI. Its predictive value was comparable with the mini-GRACE score, which could be used as a simple tool for early and rapid outcome evaluation for AMI patients.
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Fibrilación Atrial , Infarto del Miocardio , Femenino , Hospitales , Humanos , Estudios Retrospectivos , Medición de RiesgoRESUMEN
OBJECTIVES: To evaluate the effect of peri-prostatic adipose tissue (PPAT) measurements using preoperative MRI on the prediction of prostate cancer (PCa) aggressiveness in men undergoing radical prostatectomy (RP). METHODS: We performed a retrospective study on 179 consecutive patients receiving RP from June 2016 to October 2018. Clinical characteristics were collected. PPAT measurements including peri-prostatic fat area (PPFA) and peri-prostatic fat area to prostate area (PA) ratio (PPFA/PA) were calculated by MRI. Multivariable logistic regression analysis was performed to identify independent predictors of PCa lymph node metastasis (LNM). The predictive performance was estimated through ROC curves. Nomograms were created based on the predictors. RESULTS: Pathologic Gleason score positively correlated with digital rectal examination (DRE), PSA, PPFA/PA, P504S, and Ki-67 (all P < 0.05). ROC curves revealed that high PPFA and high PPFA/PA were associated with LNM (both P < 0.05). Multivariate analysis revealed that high PPFA/PA, pathologic Gleason score, pT stage, and Ki-67 were independently predictive of LNM. The nomograms were created and the C-index was 0.945. CONCLUSIONS: PPFA/PA is an independent predictor for LNM along with Gleason score, pT stage, and Ki-67. PPFA/PA may help predict LNM in men undergoing RP, thus providing adjunctive information for therapeutic strategy and prognosis.
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Tejido Adiposo/patología , Imagen por Resonancia Magnética/métodos , Prostatectomía/métodos , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/cirugía , Estudios RetrospectivosRESUMEN
BACKGROUND: It is controversial whether additional antibiotic treatment will improve cognitive function in patients with post-treatment chronic Lyme disease (PTCLD). OBJECTIVE: To determine whether antibiotic therapy improves cognitive function in two randomized double-blind placebo-controlled studies of patients with PTCLD. METHODS: A total of 129 patients with a physician-documented history of Lyme disease from three study sites in the northeast United States were studied. Seventy-eight were seropositive for IgG antibodies against Borrelia burgdorferi, and 51 were seronegative. Patients in each group were randomly assigned to receive IV ceftriaxone 2 g daily for 30 days followed by oral doxycycline 200 mg daily for 60 days or matching IV and oral placebos. Assessments were made at 90 and 180 days after treatment. Symptom severity was measured from the cognitive functioning, pain, and role functioning scales of the Medical Outcomes Study (MOS). Memory, attention, and executive functioning were assessed using objective tests. Mood was assessed using the Beck Depression Inventory and Minnesota Multiphasic Personality Inventory. RESULTS: There were no significant baseline differences between seropositive and seronegative groups. Both groups reported a high frequency of MOS symptoms, depression, and somatic complaints but had normal baseline neuropsychological test scores. The combined groups showed significant decreases in MOS symptoms, higher objective test scores, and improved mood between baseline and 90 days. However, there were no significant differences between those receiving antibiotics and placebo. CONCLUSION: Patients with post-treatment chronic Lyme disease who have symptoms but show no evidence of persisting Borrelia infection do not show objective evidence of cognitive impairment. Additional antibiotic therapy was not more beneficial than administering placebo.
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Ceftriaxona/uso terapéutico , Trastornos del Conocimiento/tratamiento farmacológico , Doxiciclina/uso terapéutico , Quimioterapia Combinada/uso terapéutico , Neuroborreliosis de Lyme/tratamiento farmacológico , Administración Oral , Afecto , Anciano , Ceftriaxona/administración & dosificación , Enfermedad Crónica , Trastornos del Conocimiento/etiología , Depresión/complicaciones , Método Doble Ciego , Doxiciclina/administración & dosificación , Femenino , Humanos , Infusiones Intravenosas , Neuroborreliosis de Lyme/complicaciones , Neuroborreliosis de Lyme/psicología , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Dolor/tratamiento farmacológico , Dolor/etiología , Trastornos de la Sensación/tratamiento farmacológico , Trastornos de la Sensación/etiología , Insuficiencia del TratamientoRESUMEN
The aim of this work is the determination of Ce environment and valence state in Cerium oxide nanoparticles prepared by the microemulsion method. X-ray absorption near-edge structure measurements at Ce L3 edge were performed on the nanoparticles as a function of annealing temperature, ranging from 298K to 873K under air condition. The experimental results support the conclusion that Ce ion, in the investigated systems, is in trivalence state when the annealing temperature is below 473K. As the temperature increases up to 623K, the XANES spectrum shows the coexistence of Ce3+ and Ce4+ states. When the temperature is higher than 623K, the spectra become identical to that of CeO2 with a distinct double-peak structure, corresponding to the Ce4+ state.
RESUMEN
BACKGROUND: It is controversial whether prolonged antibiotic treatment is effective for patients in whom symptoms persist after the recommended antibiotic treatment for acute Lyme disease. METHODS: We conducted two randomized trials: one in 78 patients who were seropositive for IgG antibodies to Borrelia burgdorferi at the time of enrollment and the other in 51 patients who were seronegative. The patients received either intravenous ceftriaxone, 2 g daily for 30 days, followed by oral doxycycline, 200 mg daily for 60 days, or matching intravenous and oral placebos. Each patient had well-documented, previously treated Lyme disease but had persistent musculoskeletal pain, neurocognitive symptoms, or dysesthesia, often associated with fatigue. The primary outcome measures were improvement on the physical- and mental-health-component summary scales of the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36)--a scale measuring the health-related quality of life--on day 180 of the study. RESULTS: After a planned interim analysis, the data and safety monitoring board recommended that the studies be discontinued because data from the first 107 patients indicated that it was highly unlikely that a significant difference in treatment efficacy between the groups would be observed with the planned full enrollment of 260 patients. Base-line assessments documented severe impairment in the patients' health-related quality of life. In intention-to-treat analyses, there were no significant differences in the outcomes with prolonged antibiotic treatment as compared with placebo. Among the seropositive patients who were treated with antibiotics, there was improvement in the score on the physical-component summary scale of the SF-36, the mental-component summary scale, or both in 37 percent, no change in 29 percent, and worsening in 34 percent; among seropositive patients receiving placebo, there was improvement in 40 percent, no change in 26 percent, and worsening in 34 percent (P=0.96 for the comparison between treatment groups). The results were similar for the seronegative patients. CONCLUSIONS: There is considerable impairment of health-related quality of life among patients with persistent symptoms despite previous antibiotic treatment for acute Lyme disease. However, in these two trials, treatment with intravenous and oral antibiotics for 90 days did not improve symptoms more than placebo.
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Antibacterianos/uso terapéutico , Ceftriaxona/uso terapéutico , Doxiciclina/uso terapéutico , Enfermedad de Lyme/tratamiento farmacológico , Administración Oral , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Anticuerpos Antibacterianos/sangre , Grupo Borrelia Burgdorferi/inmunología , Ceftriaxona/administración & dosificación , Ceftriaxona/efectos adversos , Enfermedad Crónica , Método Doble Ciego , Doxiciclina/administración & dosificación , Doxiciclina/efectos adversos , Quimioterapia Combinada , Femenino , Humanos , Inyecciones Intravenosas , Enfermedad de Lyme/inmunología , Masculino , Persona de Mediana Edad , Calidad de Vida , Insuficiencia del TratamientoRESUMEN
OBJECTIVE: To assess the role of matrix metalloproteinases (MMPs) in cartilage and bone erosions in Lyme arthritis METHODS: We examined synovial fluid from 10 patients with Lyme arthritis for the presence of MMP-2, MMP-3, MMP-9, and "aggrecanase" activity using gelatinolytic zymography and immunoblot analysis. We developed an in vitro model of Lyme arthritis using cartilage explants and observed changes in cartilage degradation in the presence of Borrelia burgdorferi and/or various protease inhibitors. RESULTS: Synovial fluid from patients with Lyme arthritis was found to contain at least 3 MMPs: gelatinase A (MMP-2), stromelysin (MMP-3), and gelatinase B (MMP-9). In addition, there was evidence in 2 patients of "aggrecanase" activity not accounted for by the above enzymes. Infection of cartilage explants with B. burgdorferi resulted in induction of MMP-3, MMP-9, and "aggrecanase" activity. Increased induction of these enzymes by B. burgdorferi alone was not sufficient to cause cartilage destruction in the explants as measured by glycosaminoglycan (GAG) and hydroxyproline release. However, addition of plasminogen, which can act as an MMP activator, to cultures resulted in significant GAG and hydroxyproline release in the presence of B. burgdorferi. The MMP inhibitor batimastat significantly reduced the GAG release and completely inhibited the collagen degradation. CONCLUSION: MMPs are found in synovial fluids from patients with Lyme arthritis and are induced from cartilage tissue by the presence of B. burgdorferi. Inhibition of MMP activity prevents B. burgdorferi-induced cartilage degradation in vitro.
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Artritis Infecciosa/enzimología , Enfermedad de Lyme/enzimología , Metaloproteinasas de la Matriz/metabolismo , Animales , Artritis Infecciosa/etiología , Western Blotting , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/aislamiento & purificación , Cartílago/química , Cartílago/citología , Bovinos , Técnicas de Cultivo , ADN Bacteriano/análisis , Endopeptidasas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Glicosaminoglicanos/análisis , Humanos , Articulación de la Rodilla/enzimología , Articulación de la Rodilla/microbiología , Enfermedad de Lyme/complicaciones , Reacción en Cadena de la Polimerasa , Líquido Sinovial/enzimología , Líquido Sinovial/microbiologíaRESUMEN
The cause of persistent arthritis in patients with Lyme disease who have received standard antibiotic therapy remains an area of debate. In this study, synovial fluid levels of matrix metalloproteinases (MMPs) were compared in persons with untreated and antibiotic-resistant Lyme arthritis. Levels of MMP-1 and MMP-3, as determined by ELISA, were higher in untreated patients (P=.0064 and P=.002, respectively), whereas levels of MMP-8 and MMP-9 were higher in antibiotic-resistant patients (P=.0002 and P=.0014, respectively). In vitro studies of chondrocyte cultures infected with Borrelia burgdorferi revealed induction of MMP-1 and MMP-3 but not of MMP-8 or MMP-9. Neither Staphylococcus aureus nor lipopolysaccharide stimulated MMP-1 or MMP-3 release from these cells. The mechanism of recognition of B. burgdorferi may be through CD14 and toll-like receptor-2, which were up-regulated in the presence of B. burgdorferi. These findings suggest different stimuli for MMP induction in untreated and antibiotic-resistant Lyme arthritis.
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Antibacterianos/uso terapéutico , Grupo Borrelia Burgdorferi/efectos de los fármacos , Enfermedad de Lyme/tratamiento farmacológico , Enfermedad de Lyme/enzimología , Metaloproteinasas de la Matriz/metabolismo , Líquido Sinovial/metabolismo , Grupo Borrelia Burgdorferi/enzimología , Células Cultivadas , Condrocitos/enzimología , Condrocitos/microbiología , Farmacorresistencia Microbiana , Ensayo de Inmunoadsorción Enzimática , Humanos , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 3 de la Matriz/metabolismo , Metaloproteinasa 8 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Membrana Sinovial/citología , Membrana Sinovial/enzimología , Membrana Sinovial/microbiologíaRESUMEN
Studies of the protein function of Borrelia burgdorferi have been limited by a lack of tools for manipulating borrelial DNA. We devised a system to study the function of a B. burgdorferi oligopeptide permease (Opp) orthologue by complementation with Escherichia coli Opp proteins. The Opp system of E. coli has been extensively studied and has well defined substrate specificities. The system is of interest in B. burgdorferi because analysis of its genome has revealed little identifiable machinery for synthesis or transport of amino acids and only a single intact peptide transporter operon. As such, peptide uptake may play a major role in nutrition for the organism. Substrate specificity for ABC peptide transporters in other organisms is determined by their substrate binding protein. The B. burgdorferi Opp operon differs from the E. coli Opp operon in that it has three separate substrate binding proteins, OppA-1, -2 and -3. In addition, B. burgdorferi has two OppA orthologues, OppA-4 and -5, encoded on separate plasmids. The substrate binding proteins interact with integral membrane proteins, OppB and OppC, to transport peptides into the cell. The process is driven by two ATP binding proteins, OppD and OppF. Using opp-deleted E. coli mutants, we transformed cells with B. burgdorferi oppA-1, -2, -4 or -5 and E. coli oppBCDF. All of the B. burgdorferi OppA proteins are able to complement E. coli OppBCDF to form a functional Opp transport system capable of transporting peptides for nutritional use. Although there is overlap in substrate specificities, the substrate specificities for B. burgdorferi OppAs are not identical to that of E. coli OppA. Transport of toxic peptides by B. burgdorferi grown in nutrient-rich medium parallels borrelial OppA substrate specificity in the complementation system. Use of this complementation system will pave the way for more detailed studies of B. burgdorferi peptide transport than currently available tools for manipulating borrelial DNA will allow.
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Proteínas Bacterianas , Grupo Borrelia Burgdorferi/enzimología , Escherichia coli/enzimología , Escherichia coli/genética , Proteínas de Transporte de Membrana/metabolismo , Secuencia de Aminoácidos , Transporte Biológico Activo , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Eliminación de Gen , Genes Bacterianos , Prueba de Complementación Genética , Proteínas de Transporte de Membrana/genética , Oligopéptidos/química , Oligopéptidos/metabolismo , Operón , Plásmidos/genéticaRESUMEN
With our better understanding of Lyme disease, we now know it is not the "great imitator" of disease it once was thought to be. Limited, identifiable syndromes can be related to Lyme disease. Most of the disease's manifestations resolve without treatment. Treatment with standard antibiotics is very effective at preventing the development of long-term sequelae. The Lyme disease vaccine is safe and effective at preventing transmission of Lyme disease. Future improvements in the care of patients with Lyme disease should focus on identifying the etiology and most effective therapies for patients with posttreatment chronic Lyme disease syndrome, determining the safety and efficacy of vaccination in children, and developing second generation vaccines with improved efficacy and dosing schedules, possibly through the addition of antigens expressed in the human host.
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Antibacterianos/administración & dosificación , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/tratamiento farmacológico , Enfermedad Aguda , Enfermedad Crónica , Ensayos Clínicos como Asunto , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Enfermedad de Lyme/prevención & control , Masculino , Pronóstico , Pruebas Serológicas/métodos , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
Levels of circulating soluble CD14 (sCD14) in patients with various stages of Lyme disease (LD) were examined. Patients with early or untreated late LD had significantly higher levels of sCD14 than did healthy controls (P=.0001 and .0007, respectively); levels returned to normal within 3 months after antibiotic therapy. Patients with persistent posttreatment symptoms of LD had sCD14 levels equivalent to those of healthy controls. Differences in the serum sCD14 levels in patients with various stages of LD are likely to be directly correlated with differences in bacterial burden, suggesting that posttreatment symptoms may not require continued presence of the organism. sCD14 levels in the cerebrospinal fluid (CSF) of patients with any stage of LD were no different from those of control subjects. Levels of synovial fluid sCD14 from patients with Borrelia burgdorferi in their joints were elevated, compared with levels in normal serum, and may play a role in the pathogenesis of arthritis.
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Receptores de Lipopolisacáridos/análisis , Enfermedad de Lyme/metabolismo , Líquido Sinovial/química , Adulto , Anciano , Humanos , Receptores de Lipopolisacáridos/sangre , Receptores de Lipopolisacáridos/líquido cefalorraquídeo , Persona de Mediana EdadRESUMEN
Surface receptors for plasminogen are expressed by many gram-positive and gram-negative bacteria and may play a role in the dissemination of organisms by binding plasminogen, which upon conversion to plasmin can digest extracellular matrix proteins. Two plasminogen binding proteins have been identified for Borrelia burgdorferi, outer surface protein A and a 70-kDa protein (BPBP). We purified BPBP by plasminogen affinity chromatography and obtained its amino acid sequence by Edman degradation of a tryptic digest. The gene coding for BPBP was isolated from a lambda-ZAP II genomic library with probes developed from sequenced portions of the protein. This gene was expressed in Escherichia coli; the recombinant product was seen by antibody raised against native BPBP and also bound 125I-labeled plasminogen. The experimentally derived amino acid sequences corresponded to the predicted sequence encoded by the BPBP gene. The deduced amino acid sequence for BPBP revealed significant similarity to p30, a 30-kDa protein of B. burgdorferi (54% identity and 65% similarity), to a 60-kDa protein in Borrelia coriaceae (66% identity and 80% similarity), to oligopeptide binding protein A of E. coli (34% identity and 57% similarity), and, more generally, to the periplasmic oligopeptide binding family of proteins.
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Proteínas Bacterianas/genética , Grupo Borrelia Burgdorferi/genética , Genes Bacterianos , Plasminógeno/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Grupo Borrelia Burgdorferi/metabolismo , Clonación Molecular , Datos de Secuencia Molecular , Peso Molecular , Unión Proteica , Alineación de SecuenciaRESUMEN
The immunopathogenesis of Lyme disease is complicated and requires a thorough understanding of the interaction among the causative organism, Borrelia burgdorferi, its tick vector, and its mammalian hosts. In vitro, animal and human studies have shown that the organism is capable of adapting to and utilizing elements from its environment to establish infection and persist despite a inducing a strong immune response. Indeed, the immune response may be responsible for many of the symptoms associated with Lyme disease. It appears that humoral immunity plays the greatest role in clearance of the organism. Cytokines released by Th 1 or Th 2 subsets of CD4+ cells have been shown to play an important role in determining outcome of the disease in animal models possibly through their effects on immunoglobulin class switching. In the small percentage of patients who have treatment resistant chronic Lyme disease, autoimmune mechanisms may play a role in persistent disease.
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Grupo Borrelia Burgdorferi/inmunología , Interacciones Huésped-Parásitos , Enfermedad de Lyme/inmunología , Animales , Formación de Anticuerpos , Autoinmunidad , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/inmunología , Enfermedad Crónica , Citocinas/inmunología , Humanos , Ratones , Ratones Endogámicos AKR , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones SCID , Células TH1/inmunología , Células Th2/inmunología , Garrapatas/microbiologíaRESUMEN
Previously, we reported an association of mitomycin C resistance and a deficiency of NAD(P)H:quinone oxidoreductase (NQO1) in HCT 116-R30A cells, a subline derived from mitomycin C-sensitive HCT 116 cells. In HCT 116 cells, we found two mRNAs coding full-length cDNAs of NQO1 differing at codon 139, one with arginine (wild type), and one with tryptophan. Only the tryptophan 139 form of mRNA was detected in HCT 116-R30A cells. In addition, an exon 4 deleted mRNA of NQO1, a product of alternative splicing, was detected in both cell lines. Analysis by semiquantitative reverse transcription-PCR showed that NQO1 mRNA coding full-length cDNAs in HCT 116-R30A cells was 15% of that present in HCT 116 cells. A Mr 26,000 protein, representing the exon 4 deleted mRNA, was not detected by polyclonal anti-NQO1 in HCT 116 sublines. Recombinant plasmids of exon 4 deleted cDNA generated a Mr 26,000 protein without enzymatic activity in Escherichia coli but not in Cos7 cells. The function of exon 4 deleted mRNA is yet unknown. The rates of decay of all NQO1 mRNAs in HCT 116 and HCT 116-R30A cells were similar. DNA sequences of the promoter regions of the NQO1 gene (-837 bp) from both cell lines did not differ from each other or from the same region of the human liver NQO1 gene. Sequences of cis elements in the 837-bp region and mRNA stability could not account for the low expression of full-length mRNA in HCT 116-R30A cells. Southern blot analysis showed the size and the intensity of the NQO1 gene in the two cell lines to be similar. This result was confirmed by semiquantitative PCR analysis of a 450-bp fragment in the NQO1 gene containing codon 139 and the exon 4 region. Digestion of this PCR-amplified fragment by restriction enzyme MspI revealed that HCT 116 cells have two heterozygous NQO1 alleles, a wild-type and a tryptophan 139 form. The functional wild-type NQO1 allele was not detected in HCT 116-R30A cells. Sensitive and resistant cell lines each contained one normal and one abnormal chromosome 16. Loss of the wild-type NQO1 allele in HCT 116-R30A cells did not result from a loss of chromosome 16 or copies of the NQO1 gene. Alteration of factor(s) such as trans-acting factors and DNA methylation may be involved in the down-regulation of NQO1 in the mitomycin C-resistant HCT 116-R30A cells.
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Neoplasias del Colon/genética , NAD(P)H Deshidrogenasa (Quinona)/genética , Antibióticos Antineoplásicos , Aberraciones Cromosómicas , Neoplasias del Colon/enzimología , Regulación hacia Abajo , Resistencia a Antineoplásicos/genética , Exones , Humanos , Cariotipificación , Mitomicina , Peso Molecular , NAD(P)H Deshidrogenasa (Quinona)/análisis , NAD(P)H Deshidrogenasa (Quinona)/deficiencia , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Regiones Promotoras Genéticas , ARN Mensajero/análisis , Células Tumorales CultivadasRESUMEN
A diaziridinylspermine analogue, 1,12-diaziridinyl-4,9-diazadodecane (NSC-667005), was synthesized as a bisalkylating agent with a polyamine backbone. DNA cross-linking was detected in the reaction of linearized pBR322 DNA with 1,12-diaziridinyl-4,9-diazadodecane at concentrations comparable with that required for cross-linking by two nitrogen mustard drugs, mechlorethamine and melphalan. A significant increase in life span of female CD2F1 mice bearing L1210 murine leukemia was observed after intravenous administration of 1,12-diaziridinyl-4,9-diazadodecane in doses of less than 2.7 mg/kg, given on days 1, 5, and 9 of treatment.
Asunto(s)
Antineoplásicos/síntesis química , Aziridinas/síntesis química , Aziridinas/farmacología , Reactivos de Enlaces Cruzados/síntesis química , ADN/efectos de los fármacos , Espermina/análogos & derivados , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Aziridinas/administración & dosificación , Aziridinas/química , Reactivos de Enlaces Cruzados/farmacología , Reactivos de Enlaces Cruzados/toxicidad , Electroforesis en Gel de Agar , Femenino , Leucemia L1210/tratamiento farmacológico , Mecloretamina/farmacología , Melfalán/farmacología , Ratones , Ratones Endogámicos , Espermina/administración & dosificación , Espermina/síntesis química , Espermina/química , Espermina/farmacología , Tiotepa/farmacologíaRESUMEN
We studied the binding of plasminogen to Borrelia burgdorferi, a spirochete which causes Lyme disease and produces no endogenous proteases which digest extracellular matrix proteins. Using 125I-labeled plasminogen, we demonstrated that B. burgdorferi bound human plasminogen and that this binding was inhibitable with unlabeled plasminogen. 125I-labeled plasminogen binding by B. burgdorferi was also inhibited by the lysine analog epsilon-aminocaproic acid. There was no significant difference in the binding of Glu- or Lys-plasminogen to B. burgdorferi. Binding of plasminogen was similar in low-passage (infectious) and high-passage (noninfectious) isolates of B. burgdorferi. Plasminogen bound to the surface of B. burgdorferi could be converted into plasmin by a human urokinase-type plasminogen activator. 125I-labeled plasminogen ligand blots of borrelial membrane proteins demonstrated two prominent binding proteins at approximately 70 and approximately 30 kDa. By Western blot (immunoblot), the 30-kDa protein was found to be outer surface protein A (Osp A) of B. burgdorferi. 125I-labeled plasminogen binding to both the 70-kDa protein and Osp A was inhibited by approximately 90% with a 1,000-fold excess of unlabeled plasminogen. By scanning densitometry, the 70-kDa band bound > 10 time more 125I-labeled plasminogen than did Osp A. An Osp A-deficient mutant of B. burgdorferi and wild-type B. burgdorferi bound equal amounts of 125I-labeled plasminogen. Ligand blots of membrane proteins from an Osp A-deficient mutant showed association of 125I-labeled plasminogen at only the 70-kDa protein. Two-dimensional gel electrophoresis showed that the 70-kDa protein had a pI of approximately 5.3, clearly separable from Osp A. The association of host plasmin(ogen) with borrelial surface proteins provides a mechanism by which B. burgdorferi can digest extracellular matrix and disseminate.
Asunto(s)
Grupo Borrelia Burgdorferi/fisiología , Plasminógeno/metabolismo , Proteínas Bacterianas/metabolismo , Humanos , Proteínas de la Membrana/metabolismoRESUMEN
We tested whether linear structural models of the mechanisms underlying flicker sensitivity could reproduce the variance-covariance matrix of temporal contrast sensitivity data. Monocular sensitivities to frequencies between 2.5 and 45 Hz were measured for 124 subjects, ages 18-88 yr. Exploratory factor analyses revealed that both a two-mechanism and a three-mechanism model could adequately account for the data. Furthermore, confirmatory factor analyses and full structural equation models, using age as an explanatory variable, supported both models, with the three-factor model giving a somewhat better representation of the data. Parsimony favors the two-mechanism model. But patterns of loss associated with pre-exudative age-related maculopathy are more easily understood in terms of three underlying mechanisms.
Asunto(s)
Envejecimiento/psicología , Sensibilidad de Contraste/fisiología , Fusión de Flicker/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Degeneración Macular/psicología , Persona de Mediana Edad , Modelos Psicológicos , Visión Monocular/fisiologíaRESUMEN
An association between the resistance to mitomycin C (MMC) and a decrease of NAD(P)H:quinone oxidoreductase (NQO1) activity was reported for a MMC-resistant subline, HCT 116-R30A, derived from MMC-sensitive HCT 116 cells. Eight NQO1 cDNA clones were isolated from these two sublines by reverse transcription-PCR. Two clones, pDT9 from HCT 116 and pDT20 from HCT 116-R30A, are the full length of 274 amino acids. These two clones differ by a T to C substitution at nucleotide 464, which results in a replacement of arginine 139 by tryptophan in the enzyme. NQO1 of pDT9 and pDT20 was expressed in Escherichia coli, purified, and shown to have a protein subunit of M(r) 30,000. The change of amino acid 139 resulted in a shift of isoelectric pH from 9.5 to 8.35 and a 60% decrease of activity in reducing MMC. All of the other six clones differ from pDT9 by a deletion of exon 4. On Northern blot, we detected two mRNA species of NQO1 (1.2 and 2.7 kilobases) due to alternative polyadenylation in all sublines. MMC-resistant sublines showed 75-90% mRNA expression relative to HCT 116 cells. Reverse transcription-PCR amplification of cDNA fragment of nucleotide 298-617 revealed two full-length mRNAs in HCT 116 cells but only one full-length mRNA in HCT 116-R30A cells. An exon 4 deletion mRNA was detected in both sublines. The two full-length mRNAs may be from either alleles or chimeras of the same gene and the exon 4 deletion mRNA is a result of alternative splicing. On Western blot, we detected only one M(r) 30,000 protein in all sublines. A substantial decrease of this protein in MMC-resistant sublines (5% of HCT 116) explained the 95% decrease of their NQO1 activity. Transcriptional regulation and posttranscriptional modification may be responsible for the disparity of gene expression of NQO1 and the low concentration of NQO1 protein in MMC-resistant sublines. Reversal of MMC resistance and the recovery of NQO1 in two revertants further supports the hypothesis that cellular control of NQO1 can modulate the cytotoxicity of MMC.