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1.
Ann Oncol ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39284382

RESUMEN

BACKGROUND: Nausea and vomiting are common adverse events associated with trastuzumab deruxtecan (T-DXd). We evaluated the efficacy of an olanzapine-based triplet regimen for preventing nausea and vomiting in patients receiving their first cycle T-DXd. PATIENTS AND METHODS: This multi-institutional, randomized, double-blind, placebo-controlled (ERICA) phase II study enrolled patients with human epidermal growth factor receptor 2-positive/human epidermal growth factor receptor 2-low metastatic breast cancer receiving their first cycle of T-DXd. Patients were randomized to olanzapine 5 mg or placebo once daily (1 : 1 ratio) from day 1 to day 6, plus a 5-hydroxytryptamine type 3 receptor antagonist and dexamethasone 6.6 mg intravenously or 8 mg orally on day 1. The total observation period was 504 h (21 days) from the first T-DXd administration. The primary endpoint was complete response (CR), defined as no emetic events and no rescue medications, in the delayed phase (24-120 h after T-DXd), with the type I error rate of 0.2 (one-sided) for the comparison. Secondary endpoints included no nausea rate in the delayed and persistent phases (120-504 h), adverse event by Common Terminology Criteria for Adverse Events (CTCAE) and patient-reported outcomes version of the CTCAE (PRO-CTCAE). RESULTS: In total, 168 patients were enrolled at 43 sites in Japan (November 2021-September 2023) with 162 patients (olanzapine, n = 80; placebo, n = 82) included in the per protocol set. The primary endpoint was met as the delayed phase CR rate was significantly greater with olanzapine than placebo (70.0% versus 56.1%, P = 0.047). Efficacy was maintained in the persistent phase (63.9% versus 44.4%). No nausea rate was also greater with olanzapine (delayed phase: 57.5% versus 37.8%; persistent phase: 51.4% versus 31.9%). CR rates in the delayed phase favored olanzapine across subgroups. Appetite loss was also decreased with olanzapine. Hyperglycemia and somnolence were mostly of low-grade severity. CONCLUSION: Olanzapine 5 mg for 6 days with 5-hydroxytryptamine type 3 receptor antagonist and dexamethasone appears effective for T-DXd-treated patients to prevent delayed and persistent nausea and vomiting.

2.
Acc Chem Res ; 50(12): 2879-2885, 2017 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-29219300

RESUMEN

A clear correlation between electronic structure and CO2 selectivity for steam reforming of methanol (SRM) was obtained with PdZn, PtZn, NiZn, and PdCd intermetallics on the basis of experiments and calculations. In order to rule out the effects of oxide supports, the intermetallic powders were simply prepared by alloying in an arc furnace followed by crushing in a mortar. PdZn and PdCd exhibit valence electronic densities of states similar to that of Cu and significant chemical shifts (larger than 1 eV) of Pd 3d states with respect to pure Pd, as verified by high-resolution hard X-ray photoelectron spectroscopy (HXPS) measurements and density functional theory (DFT) calculations. Consequently, they show the similar high selectivity of CO2 for the SRM reaction. However, this is not the case for PtZn and NiZn because of the slight differences in their valence electronic structures from that of PdZn. The interval between the Fermi level and the top of the d band is closely related to the selectivity of CO2 for the SRM: the larger the interval is, the higher is the selectivity of CO2. According to DFT calculations for bulk PdZn performed by Chen et al. ( Phys. Rev. B 2003 , 68 , 075417 ), the (111) and (100) surfaces exposing Zn and Pd in an equimolar ratio are more stable than the (001) or (110) surfaces terminated by alternative Zn or Pd layers. First-principles slab calculations for PdZn, PtZn, and NiZn show that bond breaking on the surface leads to a reduction in the d bandwidth but that the d band for stable (111) or (100) surfaces remains essentially unchanged from that of the bulk. It is intriguing that PdZn and PdCd do not contain Cu but show similar valence electronic structure and catalytic selectivity, and hence, a concept is proposed where PdZn and PdCd are regarded as pseudoelements of Cu. The basis of this concept is like electronic structure, like catalysis, which has been demonstrated by experiments and calculations. This is a logical way to enable us to look for new catalysts in which precious metals are partially or completely replaced by base metals. We do not expect that this concept can be applied to all catalytic reactions, but this approach is one of most promising ways to derive a better understanding of the origin of catalytic mechanisms and eventually allow us to design useful catalysts intentionally in the future. This Account reviews the authors' published works on this topic.

3.
Lupus ; 23(10): 1031-41, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24836587

RESUMEN

Autoantibodies to proliferating cell nuclear antigen (PCNA) are specifically, if rarely, present in systemic lupus erythematosus (SLE) patient sera. Even SLE patients lacking PCNA reactivity often show reaction to PCNA-binding protein. Here, immunoreactivity to chromatin assembly factor-1 (CAF-1), an essential molecule for DNA replication and a PCNA-binding protein, was compared for the sera of SLE patients, normal healthy controls (NHCs) and other disease controls, and in autoimmune sera reactive to standard autoantigens, by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence, and immunoblotting. CAF1 and IRF1 expression in SLE and NHC peripheral mononuclear cells were compared by quantitative real-time polymerase chain reaction. Serum interferon-γ-inducing protein-10 and anti-double-stranded (ds)DNA antibody levels were measured by ELISA. Increased CAF-1 autoimmune reactivity was recognized in SLE or serum anti-dsDNA antibody-positive patients. Significantly greater central nervous system (CNS) involvement (aseptic meningitis) and serum anti-dsDNA antibody titers were present more often in anti-CAF-1 antibody-positive than antibody-negative SLE patients. IFN-γ positively regulated CAF-1 expression in vitro and was associated with anti-CAF-1 antibody production in SLE. Thus, a novel anti-CAF-1 autoantibody is frequently found in patients with SLE and is a useful biomarker for diagnosis, especially in cases with CNS involvement. Aberrant IFN-γ regulation appears to play an important role in anti-CAF-1 antibody production in SLE.


Asunto(s)
Autoanticuerpos/sangre , Factor 1 de Ensamblaje de la Cromatina/inmunología , Lupus Eritematoso Sistémico/inmunología , Adolescente , Adulto , Anticuerpos Antinucleares/sangre , Autoinmunidad , Biomarcadores/sangre , Estudios de Casos y Controles , Células Cultivadas , Factor 1 de Ensamblaje de la Cromatina/genética , Factor 1 de Ensamblaje de la Cromatina/metabolismo , Femenino , Regulación de la Expresión Génica , Humanos , Interferón gamma/metabolismo , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/genética , Linfocitos/inmunología , Linfocitos/metabolismo , Masculino , Adulto Joven
4.
Tech Coloproctol ; 18(3): 247-55, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24043578

RESUMEN

BACKGROUND: The safety of laparoscopic surgery for rectal cancer following chemoradiotherapy (CRT) has not been fully established. The aim of our retrospective study was to examine the outcomes and the factors contributing to the difficulty of laparoscopic surgery after CRT. METHODS: Eighty-seven consecutive rectal cancer patients treated with CRT were analyzed. Clinicopathological factors were compared between laparoscopic surgery (n = 57) and open surgery (n = 30) groups, and factors that correlated with operation time and blood loss were analyzed in low anterior resection (LAR) cases in the laparoscopic surgery group (n = 46). RESULTS: There was less blood loss in the laparoscopic surgery group than in the open surgery group (191 vs. 1,043 ml, p = 0.0001), and the operation time in the two groups was similar (329 vs. 322 min, p = 0.8). The rate of conversion from laparoscopic surgery to open surgery was 1.8 %. There was no significant difference in the morbidity rate (laparoscopic surgery 22.8 % vs. open surgery 33.3 %, p = 0.3). All circumferential resection margins were clear. Three-year cumulative rates of local recurrence were as follows: laparoscopic surgery: 1.9 % vs. open surgery: 8.4 % (p = 0.4), and distant recurrence was 28.5 % in laparoscopic surgery vs. 22.7 % in open surgery (p = 0.8) and these rates were not significantly different. In laparoscopic LAR cases, a shorter distance of the tumor from the anal verge was associated with a longer operation time. A high computed tomography Hounsfield units value of the mesorectum (CTV) was associated with increased blood loss in the first 23 cases, but not in the other 23 cases. CONCLUSIONS: Laparoscopic surgery following CRT was safe and feasible. A shorter anal verge was associated with a longer operation time. Blood loss increased in cases with high CTV, but this can likely be mitigated by experience.


Asunto(s)
Quimioradioterapia , Laparoscopía , Neoplasias del Recto/cirugía , Anciano , Pérdida de Sangre Quirúrgica , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Seguridad del Paciente , Neoplasias del Recto/terapia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
5.
Anim Genet ; 44(1): 79-85, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22524237

RESUMEN

The domestic goat is one of the most important livestock species, but its origins and genetic diversity still remain uncertain. Multiple highly divergent maternal lineages of goat have been reported in previous studies. Although one of the mitochondrial DNA lineages, lineage B, was detected only in eastern and southern Asia, the geographic distribution of these lineages was previously unclear. Here, we examine the genetic diversity and phylogeographic structure of Asian goats by mitochondrial DNA sequences and morphological characteristics. The analyses of a total of 1661 Asian goats from 12 countries revealed a high frequency of lineage B in Southeast Asia. The frequency of this lineage tended to be higher in mountain areas than in plain areas in Southeast Asian countries, and there was a significant correlation between its frequency and morphological traits. The results suggest an original predominance of lineage B in Southeast Asia and the recent infiltration of lineage A into Southeast Asian goats.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Cabras/genética , Filogeografía , Animales , Asia Sudoriental , ADN Mitocondrial/sangre , Asia Oriental , Cabras/anatomía & histología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Homología de Secuencia
6.
Breast Cancer ; 30(4): 657-665, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37217763

RESUMEN

INTRODUCTION: This study described, in routine clinical practice in Japan, the patient characteristics, treatment patterns, and outcomes of female patients with HR + /HER2- metastatic breast cancer (MBC) who started abemaciclib treatment. METHODS: Clinical charts were reviewed for patients starting abemaciclib in 12/2018-08/2021 with a minimum of 3 months follow-up data post-abemaciclib initiation regardless of abemaciclib discontinuation. Patient characteristics, treatment patterns, and tumor response were descriptively summarized. Kaplan-Meier curves estimated progression-free survival (PFS). RESULTS: 200 patients from 14 institutions were included. At abemaciclib initiation, median age was 59 years, and the Eastern Cooperative Oncology Group performance status score was 0/1/2 for 102/68/5 patients (58.3/38.9/2.9%), respectively. Most had an abemaciclib starting dose of 150 mg (92.5%). The percentage of patients receiving abemaciclib as 1st, 2nd, or 3rd line treatment was 31.5%, 25.8%, and 25.2%, respectively. The most frequent endocrine therapy drugs used with abemaciclib were fulvestrant (59%) and aromatase inhibitors (40%). Evaluation of tumor response was available for 171 patients, 30.4% of whom had complete/partial response. Median PFS was 13.0 months (95% CI 10.1-15.8 months). CONCLUSIONS: In a routine clinical practice setting in Japan, patients with HR + , HER2- MBC appear to benefit from abemaciclib treatment in terms of treatment response and median PFS, with the results broadly reflecting the evidence demonstrated in clinical trials.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Persona de Mediana Edad , Neoplasias de la Mama/patología , Japón , Aminopiridinas/efectos adversos , Fulvestrant/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor ErbB-2
7.
Sci Rep ; 12(1): 13779, 2022 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-35962140

RESUMEN

SiGe is a promising anode material for replacing graphite in next generation thin-film batteries owing to its high theoretical charge/discharge capacity. Metal-induced layer exchange (LE) is a unique technique used for the low-temperature synthesis of SiGe layers on arbitrary substrates. Here, we demonstrate the synthesis of Si1-xGex (x = 0-1) layers on plastic films using Al-induced LE. The resulting SiGe layers exhibited high electrical conductivity (up to 1200 S cm-1), reflecting the self-organized doping effect of LE. Moreover, the Si1-xGex layer synthesized by the same process was adopted as the anode for the lithium-ion battery. All Si1-xGex anodes showed clear charge/discharge operation and high coulombic efficiency (≥ 97%) after 100 cycles. While the discharge capacities almost reflected the theoretical values at each x at 0.1 C, the capacity degradation with increasing current rate strongly depended on x. Si-rich samples exhibited high initial capacity and low capacity retention, while Ge-rich samples showed contrasting characteristics. In particular, the Si1-xGex layers with x ≥ 0.8 showed excellent current rate performance owing to their high electrical conductivity and low volume expansion, maintaining a high capacity (> 500 mAh g-1) even at a high current rate (10 C). Thus, we revealed the relationship between SiGe composition and anode characteristics for the SiGe layers formed by LE at low temperatures. These results will pave the way for the next generation of flexible batteries based on SiGe anodes.

8.
Lupus ; 20(12): 1231-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21980035

RESUMEN

Changes in gene expression in CD3+ T cells associated with disease progression in systemic lupus erythematosus (SLE) patients were determined. The genes related to SLE disease-related activities were identified and their gene regulatory networks were investigated. Analyses of gene expression were performed by both DNA microarray and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The expression of certain genes including interferon (IFN) regulatory factor (IRF)-related genes, such as IFN-regulated, -related, and -signature genes was increased in the active phase of SLE. Pathway network analyses suggested that these IRF-related genes are regulated through the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. JAK/STAT pathway-mediated regulation of IRF-related genes may have an important role in the disease activity of SLE. Inhibitors of JAK/STAT cascade may be useful as therapeutic agents.


Asunto(s)
Factores Reguladores del Interferón/genética , Quinasas Janus/genética , Quinasas Janus/metabolismo , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/metabolismo , Factores de Transcripción STAT/genética , Factores de Transcripción STAT/metabolismo , Adulto , Anciano , Secuencia de Bases , Cartilla de ADN/genética , Femenino , Regulación de la Expresión Génica , Humanos , Lupus Eritematoso Sistémico/inmunología , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Linfocitos T/inmunología , Adulto Joven
9.
Int Surg ; 96(1): 64-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21675623

RESUMEN

Williams syndrome is rare and associated with physical anomalies and mental retardation. It is a disease resulting from a gene deletion of chromosome 7. The main concurrent medical conditions typically associated with Williams syndrome are heart defects such as supravalvular aortic stenosis, mental retardation, and unusual physical characteristics. It is also associated with colon diverticulosis and diverticulitis. In the present article, we report on 2 cases of diverticulitis in patients with Williams syndrome, in whom surgery was performed. In many cases of diverticulitis in patients with Williams syndrome, surgical treatment is indicated. It is important to take diverticulitis into consideration when examining a patient with Williams syndrome presenting with abdominal pain and consider surgical treatment if necessary.


Asunto(s)
Diverticulitis del Colon/etiología , Diverticulitis del Colon/cirugía , Enfermedades del Sigmoide/etiología , Enfermedades del Sigmoide/cirugía , Síndrome de Williams/complicaciones , Adulto , Anciano , Diverticulitis del Colon/diagnóstico , Femenino , Humanos , Masculino , Enfermedades del Sigmoide/diagnóstico
10.
Int Surg ; 95(4): 356-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21309421

RESUMEN

Amebic colitis normally causes mucous and bloody diarrhea stool as predominant symptoms, thus leading to a course of chronic colitis. However, though rare, there exists a fulminating type that causes intestinal perforations due to wide necrosis of the large intestine. We encountered a case of fulminant amebic colitis that lead to death due to multiple large intestinal perforations. The patient was a 72-year-old female. The patient was admitted to our hospital with symptoms of fever, abdominal pain, and diarrhea. She continued to have a fever of over 38 degrees C and increased left abdominal pain. An abdominal computed tomography scan revealed free gas on the abdominal side of the kidney. Therefore, gastrointestinal perforations were diagnosed and surgery was performed. In surgery, many perforated parts were observed from the appendix to the descending colon, and subtotal colectomy was performed. However, sepsis and disseminated intravascular coagulation occurred, and the patient died on the eighth postoperative day.


Asunto(s)
Disentería Amebiana/complicaciones , Disentería Amebiana/cirugía , Perforación Intestinal/parasitología , Perforación Intestinal/cirugía , Anciano , Disentería Amebiana/diagnóstico por imagen , Resultado Fatal , Femenino , Humanos , Perforación Intestinal/diagnóstico por imagen , Tomografía Computarizada por Rayos X
11.
Clin Exp Rheumatol ; 27(2): 260-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19473566

RESUMEN

OBJECTIVE: The incidence of systemic lupus erythematosus (SLE) is far higher in females than in males and the onset and/or disease activity is influenced by pregnancy and the menstrual cycle. Sex hormones seem to influence the pathogenesis of SLE, therefore, changes in gene expression in peripheral blood mononuclear cells (PBMC) were examined during the menstrual cycle in females, under the comparison of gene expression of patients with SLE. METHODS: The detection and a quantitative analysis of the gene expression was performed by DNA microarray or real-time quantitative polymerase chain reaction (RQ-PCR) method. RESULTS: There were thirteen known genes which showed significant quantitative changes during the menstrual cycles of females, but not in males. Among these genes, statistical quantitative differences between normal controls and SLE patients were observed in six genes. CONCLUSION: Based on these findings, certain genes (such as the tumor necrosis factor receptor superfamily, member 14; TNFRSF14, and signal regulatory protein, gamma; SIRPG) appear to contribute to gender difference of SLE.


Asunto(s)
Perfilación de la Expresión Génica , Leucocitos Mononucleares/metabolismo , Lupus Eritematoso Sistémico/genética , Ciclo Menstrual/genética , Adulto , Antígenos de Diferenciación/genética , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Humanos , Lupus Eritematoso Sistémico/sangre , Masculino , Ciclo Menstrual/metabolismo , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores Inmunológicos/genética , Miembro 14 de Receptores del Factor de Necrosis Tumoral/genética , Factores Sexuales , Regulación hacia Arriba
12.
Andrology ; 7(5): 644-653, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30927342

RESUMEN

BACKGROUND: Spermatozoa become competent for fertilization during transit through the epididymis. As spermatozoa from the proximal caudal epididymis can fertilize eggs, proteins from the caput and corpus epididymis are required for sperm maturation. OBJECTIVES: Microarray analysis identified that more than 17,000 genes are expressed in the epididymis; however, few of these genes demonstrate expression restricted to the epididymis. To analyze epididymis-enriched gene function in vivo, we generated knockout (KO) mutations in nine genes that are abundantly expressed in the caput and corpus region of the epididymis. MATERIALS AND METHODS: KO mice were generated using the CRISPR/Cas9 system. The histology of the epididymis was observed with hematoxylin and eosin staining. KO males were caged with wild-type females for 3-6 months to check fertility. RESULTS: We generated individual mutant mouse lines having indel mutations in Pate1, Pate2, or Pate3. We also deleted the coding regions of Clpsl2, Epp13, and Rnase13, independently. Finally, the 150 kb region encoding Gm1110, Glb1l2, and Glb1l3 was deleted to generate a triple KO mouse line. Histology of the epididymis and sperm morphology of all KO lines were comparable to control males. The females mated with these KO males delivered pups at comparable numbers as control males. DISCUSSION AND CONCLUSION: We revealed that nine genes abundantly expressed in the caput and corpus epididymis are dispensable for sperm function and male fecundity. CRISPR/Cas9-mediated KO mice generation accelerates the screening of epididymis-enriched genes for potential functions in reproduction.


Asunto(s)
Epidídimo/metabolismo , Fertilidad/genética , Proteínas de la Membrana/genética , Espermatozoides/metabolismo , Animales , Sistemas CRISPR-Cas , Técnicas de Inactivación de Genes , Masculino , Ratones , Ratones Noqueados , Maduración del Esperma/fisiología , Motilidad Espermática/genética
13.
Rheumatology (Oxford) ; 47(2): 145-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18160420

RESUMEN

OBJECTIVES: Toll-like receptor 9 (TLR9) is a pattern-associated receptor functioning in innate immunity that may be involved in the recognition of self-antigens and the production of pathogenic auto-antibodies. Therefore, we examined the expression of TLR9 in systemic lupus erythematosus (SLE) to determine whether TLR9 is involved in the production of pathogenic auto-antibodies. METHODS: B cells were collected from patients with active SLE, and subjected to analysis of the TLR9 molecule using flow cytometry fluorescence activated cell sorting (FACS) and TLR9 mRNA by reverse-transcriptase polymerase chain reaction. SLE B cells were stimulated with CpG-ODN, and subsequent cytokine and anti-dsDNA antibody production was measured by enzyme-linked immunosorbent assay. RESULTS: The expression and mRNA level of TLR9 on B cells was up-regulated in SLE patients, and SLE disease activity index (SLEDAI) and CH50 were correlated with TLR9 expression on CD20+ B cells. Moreover, TLR9-CpG interaction enhanced the production of anti-dsDNA antibody and IL-10. CONCLUSIONS: The present study demonstrated that higher expression of TLR9 on peripheral blood B cells from patients with active SLE was significantly correlated with CH50 and SLEDAI to TLR9, and induced the production of anti-dsDNA antibody and IL-10 by TLR9-CpG ligation. These results suggest that an abnormality of innate immunity plays a crucial role in the pathology of SLE, and that blockade of CpG-TLR9 interaction may be a new therapeutic approach for SLE.


Asunto(s)
Autoanticuerpos/inmunología , Linfocitos B/inmunología , Lupus Eritematoso Sistémico/inmunología , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/inmunología , Adolescente , Adulto , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Autoanticuerpos/genética , Islas de CpG/inmunología , Femenino , Citometría de Flujo , Regulación de la Expresión Génica/inmunología , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , Valores de Referencia
16.
Nucleic Acids Res ; 28(16): 3117-24, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10931927

RESUMEN

Among the polymerases, DNA polymerase alpha-primase is involved in lagging strand DNA synthesis. A previous report indicated that DNA polymerase alpha-primase initiates primer RNA synthesis with purine bases on a single-stranded G-rich telomere repeat. In this study, we found that DNA polymerase alpha-primase precisely initiated with adenosine opposite the 3'-side thymidine in the G-rich telomere repeat 5'-(TTAGGG)(n)-3' under rATP-rich conditions. Then, DNA polymerase alpha-primase synthesized the nascent DNA fragments by extending the primer. It was remarkable that DNA polymerase alpha-primase further expanded the product DNA far beyond the length of the template DNA, as ladders of multiple hexanucleotides on polyacrylamide gel electrophoresis. Using an oligomer duplex 5'-A(GGGTTA)(5)-3'/5'-(TAACCC)(5)T-3' as a template-primer, we show that both the Klenow fragment of Escherichia coli DNA polymerase I and HIV reverse transcriptase could expand telomere DNA sequences as well, giving products greater than the size of the template DNA. The maximum product lengths with these polymerases were approximately 40-90 nt longer than the template length. Our data imply that DNA polymerases have an intrinsic activity to expand the hexanucleotide repeats of the telomere sequence by a slippage mechanism and that DNA polymerase alpha uses both the repeat DNA primers and the de novo RNA primers for expansion. On the other hand, a plasmid harboring a eukaryotic telomere repeat showed remarkable genetic instability in E.coli. The telomere repeats exhibited either expansions or deletions by multiple hexanucleotide repeats during culture for a number of generations, suggesting involvement of the slippage mechanism in the instability of telomeric DNA in vivo.


Asunto(s)
ADN Polimerasa I/metabolismo , ADN Primasa/metabolismo , Escherichia coli/genética , Secuencias Repetitivas de Ácidos Nucleicos , Telómero/metabolismo , Animales , Secuencia de Bases , Bovinos , Cartilla de ADN , Escherichia coli/enzimología , Guanina , Plásmidos , Eliminación de Secuencia , Especificidad por Sustrato , Moldes Genéticos , Timo/enzimología
17.
AJNR Am J Neuroradiol ; 37(8): 1528-34, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27056422

RESUMEN

BACKGROUND AND PURPOSE: T1-weighted pointwise encoding time reduction with radial acquisition (PETRA) sequences require limited gradient activity and allow quiet scanning. We aimed to assess the usefulness of PETRA in pediatric brain imaging. MATERIALS AND METHODS: We included consecutive pediatric patients who underwent both MPRAGE and PETRA. The contrast-to-noise and contrast ratios between WM and GM were compared in the cerebellar WM, internal capsule, and corpus callosum. The degree of myelination was rated by using 4-point scales at each of these locations plus the subcortical WM in the anterior frontal, anterior temporal, and posterior occipital lobes. Two radiologists made all assessments, and the intra- and interrater agreement was calculated by using intraclass correlation coefficients. Acoustic noise on MPRAGE and PETRA was measured. RESULTS: We included 56 patients 5 days to 14 years of age (mean age, 36.6 months) who underwent both MPRAGE and PETRA. The contrast-to-noise and contrast ratios for PETRA were significantly higher than those for MPRAGE (P < .05), excluding the signal ratio for cerebellar WM. Excellent intra- and interrater agreement were obtained for myelination at all locations except the cerebellar WM. The acoustic noise on PETRA (58.2 dB[A]) was much lower than that on MPRAGE (87.4 dB[A]). CONCLUSIONS: PETRA generally showed better objective imaging quality without a difference in subjective image-quality evaluation and produced much less acoustic noise compared with MPRAGE. We conclude that PETRA can substitute for MPRAGE in pediatric brain imaging.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Vaina de Mielina
18.
Endocrinology ; 137(5): 1878-84, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8612527

RESUMEN

Recent evidence suggests that lipoxygenase (LO) metabolites inhibit renin production in vitro. However, the physiological significance of this effect has not been determined. This study examined the role of the LO pathway in the regulation of plasma renin concentration (PRC) in vivo. The acute administration of two structurally unrelated LO inhibitors, phenidone (30 and 60 mg/kg) and esculetin (60 mg/kg), resulted in suppression of platelet 12 hydroxyeicosatetraenoic acid (12HETE) production, reduction in systemic arterial pressure and a 2- to 3-fold increase in PRC. To determine whether the esculetin-induced increase in PRC was secondary to hypotension, esculetin was also administered to rats preinfused with a pressor dose of norepinephrine. In these acutely hypertensive rats, esculetin still induced a 2.5-fold increase in PRC, whereas blood pressure remained over 40 mm Hg above basal levels. Further, esculetin (10(-6)M) increased renin release in renal slices from 150 +/- 10 to 310 +/- 20 ng/ml.h (P < 0.05) and this rise was entirely blocked in the presence of 12HETE (10(-7)M; 130 +/- 40 ng/ml.h). In rats placed on high salt intake, 12HETE concentration in renal slices from the outer cortex was considerably higher than in renal slices from salt-restricted rats (116.5 +/- 15.7 vs. 65 +/- 12 pg/mg protein; P < 0.05). Chronic administration of the LO inhibitor phenidone also resulted in an increase of PRC, which was independent of changes in blood pressure. On either high salt (3.15%0 or low salt (0.05%) diet phenidone-treated rats had higher PRC levels than the respective control groups [high salt 9.7 +/- 3.5 vs. 1.9 +/- 1.4 ng/ml.h; P < 0.05; low salt 33.2 +/- 5.3 vs. 19.4 +/- 3.10 ng/ml.h; P < 0.05]. The finding that LO blockers are potent stimulators of PRC in vivo suggests the existence of a physiological tonic inhibition of renin secretion by LO products that is operative under a wide range of salt intake. High salt intake enhances this inhibitory tone by increasing renal cortical 12 LO activity and, in fact, normal suppression of PRC during high salt diet does not occur in LO-blocked animals. Thus, the LO pathway exerts a tonic inhibitory effect on renin release, which appears particularly important for renin suppression during high salt intake.


Asunto(s)
Araquidonato 12-Lipooxigenasa/metabolismo , Renina/antagonistas & inhibidores , Renina/metabolismo , Sodio en la Dieta/administración & dosificación , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico , Animales , Plaquetas/metabolismo , Inhibidores Enzimáticos/farmacología , Ácidos Hidroxieicosatetraenoicos/sangre , Ácidos Hidroxieicosatetraenoicos/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Inhibidores de la Lipooxigenasa , Masculino , Norepinefrina/farmacología , Pirazoles/farmacología , Ratas , Ratas Sprague-Dawley , Renina/sangre , Umbeliferonas/farmacología
19.
Autoimmunity ; 34(1): 19-25, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11681489

RESUMEN

The levels of interleukin-13 (IL-13) in patients with systemic lupus erythematosus (SLE) were examined and related to other Th1-/Th2- related cytokines, clinical manifestations and other markers. Serum levels of IL-13 and other cytokines, soluble markers were measured by enzyme-linked immunosorbent assay (ELISA). Patients with active SLE had a significantly increased level of IL-13. Most patients with high levels of IL-13 had higher levels of IL-6, and some patients had high levels of gammaIFN. These patients were divided into two groups according to the patterns of these increased cytokines; one with a high level of only Th2 related cytokines (IL-13 or IL-6) and another with high levels of both Th2 related and Th1 related cytokines (gammaIFN or IL-2). The latter patients had high levels of soluble CD8 and CD23, and some of them had hemolytic anemia or pulmonary involvement, while most of the former patients had nephropathy. Thus, in SLE, the levels of IL-13 were increased, and the heterogeneity of increased Th2- and Th1-related cytokines was related to that of activation markers and clinical manifestations.


Asunto(s)
Citocinas/sangre , Interleucina-13/sangre , Lupus Eritematoso Sistémico/inmunología , Células TH1/inmunología , Células Th2/inmunología , Adulto , Biomarcadores/sangre , Antígenos CD4/sangre , Antígenos CD8/sangre , Estudios de Casos y Controles , Femenino , Humanos , Interferón gamma/sangre , Interleucina-2/sangre , Interleucina-6/sangre , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de IgE/sangre
20.
Am J Hypertens ; 2(11 Pt 1): 853-5, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2511900

RESUMEN

This study examined the role of the lipoxygenase (LO) pathway in the maintenance of hypertension in rats with two-kidney, one clip (2K,1C) Goldblatt hypertension. A single dose of the lipoxygenase blocker phenidone was injected intraperitoneally to 2K,1C rats during the early phase (14 days) of the development of hypertension (mean intraarterial blood pressure 137 +/- 3.9 mm Hg). Phenidone (60 mg/kg) markedly decreased arterial pressure to nadir levels of 58.9% of resting blood pressure. The maximal changes were observed 15 min after injection and the hypotensive response was sustained for at least 2 h. Plasma renin concentration (PRC) increased from 74.3 +/- 18.9 to 281.0 +/- 6.5 ng/mL/h after injection (P less than .05). Thus, the hypotensive effect of phenidone was not due to suppression of renin secretion but presumably due to inhibition of its effects. It is suggested that arachidonate metabolites of the LO pathway at the vascular bed may be involved in maintenance of high arterial pressure in 2K,1C renovascular hypertension in rat.


Asunto(s)
Hipertensión Renovascular/tratamiento farmacológico , Pirazoles/uso terapéutico , Animales , Ácido Araquidónico , Ácidos Araquidónicos/metabolismo , Presión Sanguínea/efectos de los fármacos , Hipertensión Renovascular/fisiopatología , Inhibidores de la Lipooxigenasa , Masculino , Ratas , Ratas Endogámicas , Renina/sangre
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